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Interventions for replacing missing teeth: augmentation procedures of the maxillary sinus

  1. Marco Esposito1,*,
  2. Pietro Felice2,
  3. Helen V Worthington1

Editorial Group: Cochrane Oral Health Group

Published Online: 13 MAY 2014

Assessed as up-to-date: 17 JAN 2014

DOI: 10.1002/14651858.CD008397.pub2


How to Cite

Esposito M, Felice P, Worthington HV. Interventions for replacing missing teeth: augmentation procedures of the maxillary sinus. Cochrane Database of Systematic Reviews 2014, Issue 5. Art. No.: CD008397. DOI: 10.1002/14651858.CD008397.pub2.

Author Information

  1. 1

    School of Dentistry, The University of Manchester, Cochrane Oral Health Group, Manchester, UK

  2. 2

    University of Bologna, Department of Oral and Dental Sciences, Bologna, Italy

*Marco Esposito, Cochrane Oral Health Group, School of Dentistry, The University of Manchester, Coupland 3 Building, Oxford Road, Manchester, M13 9PL, UK. espositomarco@hotmail.com.

Publication History

  1. Publication Status: New search for studies and content updated (conclusions changed)
  2. Published Online: 13 MAY 2014

SEARCH

 
Characteristics of included studies [ordered by study ID]
Cannizzaro 2009

MethodsRandomised trial of parallel group design, 5-year post-loading follow-up. 1 drop-out from the lateral window sinus lift group who died of cancer just before the 3-year post-loading follow-up


ParticipantsPatients having 3 to 6 mm of alveolar bone at the floor of the sinus. Adults treated at a private dental practice, Pavia, Italy. Exclusion criteria were: general contraindications to implant surgery, subjected to irradiation in the head and neck area less than 1 year ago, treated or under treatment with intravenous amino-bisphosphonates, poor oral hygiene and motivation, uncontrolled diabetes, pregnant or lactating, substance abusers, psychiatric problems or unrealistic expectations, lack of opposite occluding dentition/prosthesis in the area intended for implant placement, acute infection in the area intended for implant placement. 20 patients were treated in each group


Interventions1-stage sinus lift using 1 to 3 8 mm long implants placed in simultaneously crestally augmented sinus with autogenous particulate bone, harvested from the implant site, versus 1 to 3 10 mm or longer implants placed in simultaneously augmented sinuses using the lateral approach with a mixture of 50% particulate autogenous bone from the tuberosity area and 50% Bio-Oss. A modified 'Cosci technique' was used to crestally augment the sinus. In brief implant sites were prepared with a 2.5 mm trephine drill up to about 1 mm of the sinus cortical wall, to collect autogenous bone, and with a 3.1 mm diameter atraumatic lifting drill. Resorbable barriers (Biomend Extend, Sulzer Dental Inc., Carlsbad, CA, USA) were used to seal the lateral windows. All the augmentation procedures were performed under local anaesthesia. All implants were left to heal submerged for 45 days and were functionally loaded within 1 week after abutment connection. All implants were tapered Screw-Vent MP-1 HA Dual Transition Selective Surface implants (Zimmer Dental, Carlsbad, CA, USA) inserted in under prepared osteotomy sites with a torque of at least 35 N/cm


OutcomesProsthesis and implant failures, complications at the augmented and donor sites, and peri-implant marginal bone levels


Notes


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Low riskArticle: "A computer generated restricted randomisation list was created"

Allocation concealment (selection bias)Low riskArticle: "Only one of the investigators (Marco Esposito), not involved in the selection and treatment of the patients, was aware of the randomization sequence and could have access to the randomization list stored in his pass-word protected portable computer. The randomized codes were enclosed in sequentially numbered, identical, opaque, sealed envelopes. Envelopes were opened sequentially after eligible patients were anaesthetised, therefore, treatment allocation was concealed to the investigators in charge of enrolling and treating the patients"

Blinding of outcome assessment (detection bias)
All outcomes
Low riskArticle: "One dentist (Giuseppe Fontana) not involved in the treatment of the patients made all the clinical assessments without knowing group allocation, therefore outcome assessor was blinded, however Bio-Oss augmented sites could be identified on radiographs because they appeared more radio-opaque and implants were longer"

Incomplete outcome data (attrition bias)
All outcomes
Low riskAll data presented, no drop-outs

Selective reporting (reporting bias)Low riskAll planned outcomes were reported

Other biasUnclear riskThe 8 mm implants were in general of larger diameter than the longer implants, therefore it cannot be ruled out that also the implant diameter played a role in the clinical outcome

Checchi 2010

MethodsRandomised trial of split-mouth design, 1 year post-loading follow-up. 3 withdrawals between years 1 and 3


ParticipantsPatients having 5 to 7 mm of alveolar bone height with a thickness of 5 mm or more below the sinus. Adults treated in 2 private practices in Bologna, Italy. Exclusion criteria were: general contraindications to implant surgery, subjected to irradiation in the head and neck area, treated or under treatment with intravenous amino-bisphosphonates, poor oral hygiene and motivation, untreated periodontal disease, uncontrolled diabetes, pregnant or lactating, substance abusers, psychiatric problems or unrealistic expectations, lack of opposite occluding dentition/prosthesis in the area intended for implant placement, acute or chronic infection/inflammation in the area intended for implant placement, patients participating in other trials, if the present protocol could not be properly followed, referred only for implant placement. 15 patients were treated and 12 patients were followed up to 3 years after loading


Interventions1-stage crestal sinus lift according to the Summers' technique using dedicated osteotomes of increasing diameters and a mallet versus the Cosci's technique using dedicated rotatory instruments with increasing working lengths and finally a special drill with a non-cutting head (atraumatic lifting drill). Particulate cancellous human allograft (Puros, Zimmer Dental, Carlsbad, Ca, USA) was used. Augmentation procedures were performed under local anaesthesia and 1 or 2 8 to 10 mm long TSV Screw-Vent tapered implants with internal connection and MTX microtextured titanium surface (Zimmer Dental) were placed and submerged for 6 months. Provisional screw-retained reinforced resin prostheses were replaced after 4 months by definitive provisionally cemented metal-ceramic prostheses


OutcomesProsthesis, implant and augmentation failures, complications, patient preference 1 and 5 months after augmentation, peri-implant marginal bone level changes, operator preference, duration of the sinus lift procedures


Notes


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Low riskArticle: "A computer generated restricted randomisation list was created.Only one of the investigators (Marco Esposito), not involved in the selection and treatment of the patients, was aware of the randomisation sequence and could have access to the randomisation list stored in his pass-word protected portable computer"

Allocation concealment (selection bias)Low riskArticle: "The randomised codes were enclosed in sequentially numbered, identical, opaque, sealed envelopes. Envelopes were opened sequentially after flap elevation, therefore, treatment allocation was concealed to the investigators in charge of enrolling and treating the patients"

Blinding of outcome assessment (detection bias)
All outcomes
Low riskArticle: "Follow-ups were conducted by an independent blind outcome assessor (Gerardo Pellegrino)"

Incomplete outcome data (attrition bias)
All outcomes
Low riskAll data presented, no drop-outs

Selective reporting (reporting bias)Low riskAll planned outcomes were reported

Other biasHigh risk8 out of 15 patients were treated by Dr Cosci who was the inventor of the Cosci's technique

Crespi 2012

MethodsRandomised trial of parallel group design, 19-month post-loading follow-up. No withdrawals


ParticipantsPatients having an unspecified "inadequate" alveolar bone height below the sinus and bone quality of type 3 or 4. Adults treated at the Department of Dentristy, San Raffaele Hospital, Milan, Italy. Exclusion criteria were: smoking, any chronic systemic disease and acute or chronic sinus problems, coagulation disorders, sing of acute infection around the alveolar bone at the site, alcohol and drug abuse. 40 patients were treated in each group


Interventions1-stage crestal sinus lift with osteotomes and hand mallet versus electric mallet (Magnetic Mallet MetaErgonomica, Turbigo (MI), Italy). Augmentation procedures were performed under local anaesthesia, no grafting material was used and Outlink tapered implants (Sweden & Martina, Due Carrare (PD), Italy), with external hexagon connection, titanium plasma-spayed surface and 0.8 mm of polished neck, were left to heal submerged for 3 months. Provisional prostheses were replaced after 2 months by definitive screw-retained metal-ceramic prostheses


OutcomesProsthesis, implant and augmentation failures, complications, patient preference, vertical bone gain and maintenance over time, peri-implant marginal bone level changes, probing pocket depths, pain, modified plaque index and modified marginal bleeding index


Notes


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Unclear riskArticle: "...group assignment was performed by lots in closed envelopes"

Author's reply: "Each patient was assigned to control or test group by lots in closed envelopes"

Allocation concealment (selection bias)Unclear riskArticle: "...group assignment was performed by lots in closed envelopes"

Author's reply: "Each patient was assigned to control or test group by lots in closed envelopes"

Blinding of outcome assessment (detection bias)
All outcomes
Low riskArticle: "A blinded radiologist measured the changes in marginal bone height over time"

Authors' reply: "In measuring all clinical and radiographic parameters, the assessors were blinded anyhow"

Incomplete outcome data (attrition bias)
All outcomes
Low riskNo mention regarding drop-outs in the text

Authors' reply: "No drop-out occurred"

Selective reporting (reporting bias)High riskComplication data apparently not fully reported; for some other outcomes (PD) data not provided by study group, for other outcomes (modified plaque index and modified bleeding index) data not provided at all

Authors' reply: "No, we didn't find other complications"

Other biasLow riskNone apparent

Esposito 2012

MethodsRandomised trial of split-mouth design, 1 year post-loading follow-up. No withdrawals


ParticipantsPatients having 5 to 7 mm of alveolar bone height with a thickness of 6 mm or more below the sinus. Adults treated in dental hospitals/university clinics and private practices in Bologna, Roma and Chieti, Italy. Exclusion criteria were: general contraindications to implant surgery, patients irradiated in the head and neck area, immunosuppressed or immunocompromised patients, patients who took or are taking bisphosphonates intravenously, patients with untreated periodontitis, poor oral hygiene and motivation, uncontrolled diabetes, pregnancy or lactation, addiction to alcohol or drugs, psychiatric problems, lack of opposite occluding dentition in the area intended for implant placement, patients with an acute or chronic infection inflammation in the area intended for implant placement. 20 patients were treated and followed up to 1 year after loading


InterventionsComparison 1: short implants without augmentation versus long implants with augmentation

1 to 3 6 mm long implants of 4 mm in diameter versus 1 to 3 10 mm or longer implants of 4 mm in diameter placed in 1-stage laterally augmented sinuses with 100% cortical porcine-derived collagenated bone (Gen-Os, OsteoBiol, Tecnoss Dental, Pianezza, TO, Italy) with their lateral windows sealed with a resorbable collagen membrane from equine pericardium (Evolution, Fine 30 x 30 mm, OsteoBiol) simultaneously to implant placement. Augmentation procedures were performed under local anaesthesia and implants were left to heal submerged for 4 months. Southern implants (Irene, South Africa), with external hexagon connection, were used. Provisional screw-retained reinforced resin prostheses were replaced after 4 months by definitive screw-retained or provisionally cemented metal-ceramic prostheses


OutcomesProsthesis and implant failures, complications, peri-implant marginal bone levels and patient preference at 5 months post-loading


Notes


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Low riskArticle: "A computer generated restricted random list was created"

Allocation concealment (selection bias)Low riskArticle: "Only one of the investigators (ME), not involved in the selection and treatment of the patients, was aware of the random sequence and could have access to the random list stored in his pass-word protected portable computer. The information on how to treat site number 1 was enclosed in sequentially numbered, identical, opaque, sealed envelopes. Envelopes were opened sequentially before giving anaesthesia and surgeons should have treated both sites in the same surgical session, starting from the intervention allocated to site number 1. Therefore, treatment allocation was concealed to the investigators in charge of enrolling and treating the patients"

Blinding of outcome assessment (detection bias)
All outcomes
Low riskArticle: "Two dentists (Dr Gerardo Pellegrino and Valeria Corvino) not involved in the treatment of the patients performed all clinical measurements without knowing group allocation..."

Incomplete outcome data (attrition bias)
All outcomes
Low riskAll data presented, no drop outs

Selective reporting (reporting bias)Low riskAll planned outcomes were reported

Other biasLow riskNone apparent

Felice 2009a

MethodsRandomised trial of split-mouth design, 1 year post-loading follow-up. No withdrawals


ParticipantsPatients having 4 to 6 mm of alveolar height with a thickness of 8 mm or more below the sinus. Adults treated in dental hospitals/university clinics in Bologna, Roma and Chieti, Italy. Exclusion criteria were: general contraindications to implant surgery, patients irradiated in the head and neck area, immunosuppressed or immunocompromised patients, patients who took or are taking bisphosphonates intravenously, patients with untreated periodontitis, poor oral hygiene and motivation, uncontrolled diabetes, pregnancy or lactation, addiction to alcohol or drugs, psychiatric problems, lack of opposite occluding dentition in the area intended for implant placement, patients with an acute or chronic infection inflammation in the area intended for implant placement. 15 patients were treated and all patients were followed up to 1 year after loading, therefore there were no drop-outs


InterventionsComparison 1: short implants without augmentation versus long implants with augmentation

1 to 3 5 mm long implants of 6 mm in diameter versus 1 to 3 10 mm or longer implants of 4 mm in diameter placed in 2-stage laterally augmented sinus with 100% bovine anorganic bone (Bio-Oss, Geistlich Pharmaceutical, Wolhusen, Switzerland) with their lateral windows sealed with a resorbable collagen membrane (OsseoGuard, Biomet 3i, Palm Beach, FL, USA) 4 months before. All augmentation procedures were performed under local anaesthesia. All implants were left to left to heal submerged for 4 months. Rescue implants (MegaGen Implant Co. Lld., Gyeongbuk, South Korea) as short implants and EZ Plus (MegaGen) as long implants, all with internal connection were used. Implant site preparation was also different since a 5 mm diameter trephine was used initially to prepare the osteotomy sites for Rescue implants. Provisional screw-retained reinforced resin prostheses were replaced after 4 months by definitive screw-retained metal-ceramic prostheses


OutcomesProsthesis and implant failures, complications, peri-implant marginal bone levels, and patient preference


Notes


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Low riskArticle: "A computer generated restricted randomisation list was created"

Allocation concealment (selection bias)Low riskArticle: "Only one of the investigators (ME), not involved in the selection and treatment of the patients, was aware of the randomisation sequence and could have access to the randomisation list stored in his pass-word protected portable computer. The randomised codes were enclosed in sequentially numbered, identical, opaque, sealed envelopes. Envelopes indicating which site to augment were opened sequentially just prior to the augmentation procedure. Therefore, treatment allocation was concealed to the investigators in charge of enrolling and treating the patients"

Blinding of outcome assessment (detection bias)
All outcomes
Low riskArticle: "One dentist (GP) not involved in the treatment of the patients performed all clinical and radiographic assessments without knowing group allocation, therefore the outcome assessor was blinded, however the Bio-Oss augmented sites could be identified both clinically when testing implant stability because of the different diameters and on radiographs because they appeared more radio-opaque and implants were different"

Incomplete outcome data (attrition bias)
All outcomes
Low riskAll data presented, no drop-outs

Selective reporting (reporting bias)Low riskAll planned outcomes were reported

Other biasHigh riskImplants of small diameter (4 mm) and of different design were inserted with a different surgical technique in the augmented group instead of the originally planned identical but longer implants

Patients had always the augmentation procedure performed first and then had implant placement bilaterally. This may have affected patient preference since patient could not experience the benefit of having the prosthesis 4 months earlier

Felice 2009b

MethodsRandomised trial of split-mouth design, 1 year post-loading follow-up. 1 patient, who had a complication, dropped out before prosthetic loading


ParticipantsPatients having 1 to 4 mm of alveolar bone at the floor of the sinus. Adults treated in dental hospitals/university clinics in Bologna, Roma and Chieti, Italy. Exclusion criteria were: general contraindications to implant surgery, patients irradiated in the head and neck area, immunosuppressed or immunocompromised patients, patients who took or are taking bisphosphonates intravenously, patients with untreated periodontitis, poor oral hygiene and motivation, uncontrolled diabetes, pregnancy or lactation, addiction to alcohol or drugs, psychiatric problems, lack of opposite occluding dentition in the area intended for implant placement, patients with an acute or chronic infection inflammation in the area intended for implant placement. 10 patients were treated


Interventions2-stage sinus lift with lateral window approach using either a synthetic resorbable barrier (Inion, GTR Biodegradable Membrane System, Tampere, Finland) to keep the sinus membrane or 100% granular Bio-Oss. Inion barriers were used to seal the lateral windows. Inion barriers are made of a synthetic co-polymer (trimethylene carbonate l-lactide polyglycolide) that needs to be softened in a plasticising solution, allowing the membrane to be cut and mould to fit exactly the space. The barrier then harden in the new position maintaining the new shape and the space. This material should biodegrade in situ after 8-12 weeks. All augmentation procedures were performed under local anaesthesia. After 6 months, 1 to 3 implants were placed per side and submerged for 4 months. Implants were Way (Geass, Pozzuolo del Friuli (UD), Italy) with a laser treated surface and internal connection. Provisional screw-retained reinforced resin prostheses were replaced after 4 months by definitive screw-retained metal-ceramic prostheses. 1 patient was excluded after perforation


OutcomesProsthesis and implant failures, complications, amount of vertically augmented bone (mm), peri-implant marginal bone levels, patient and clinician preference. Time necessary to complete the augmentation procedure


Notes


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Low riskArticle: "A computer generated restricted randomisation list was created"

Allocation concealment (selection bias)Low riskArticle: "Only one of the investigators (Marco Esposito), not involved in the selection and treatment of the patients, was aware of the randomization sequence and could have access to the randomization list stored in his pass-word protected portable computer. The randomized codes were enclosed in sequentially numbered, identical, opaque, sealed envelopes. Envelopes were opened sequentially after the sinus lining epithelium of site number 1 was lifted, therefore, treatment allocation was concealed to the investigators in charge of enrolling and treating the patients"

Blinding of outcome assessment (detection bias)
All outcomes
Low riskArticle: "One dentist (Gerardo Pellegrino), not involved in the treatment of the patients, made all the clinical assessments without knowing group allocation, therefore outcome assessor was blinded, however Bio-Oss augmented sites could be identified on radiographs because they appeared more radio-opaque while Inion treated sites appeared rather radiolucent"

Incomplete outcome data (attrition bias)
All outcomes
Low riskAll data presented, 1 drop-out after perforation

Selective reporting (reporting bias)Low riskAll planned outcomes were reported

Other biasLow riskNone apparent

Felice 2011

MethodsRandomised trial of parallel group design, 5-month post-loading follow-up. No withdrawals


ParticipantsPatients with fully edentulous maxillas having residual bone heights of 5 to 9 mm with a thickness of 5 mm at the implant sites. Adults treated in dental hospitals/university clinics in Bologna, Roma, Italy. Exclusion criteria were: general contraindications to implant surgery, patients irradiated in the head and neck area, immunosuppressed or immunocompromised patients, patients who took or are taking bisphosphonates intravenously, patients with untreated periodontitis, poor oral hygiene and motivation, uncontrolled diabetes, pregnancy or lactation, addiction to alcohol or drugs, psychiatric problems, severe intermaxillary discrepancies, patients with an acute or chronic infection inflammation in the area intended for implant placement, lack of opposite occluding dentition/prosthesis. 28 patients were treated, 15 with short implants and 13 with long implants after augmentation. Patients were followed up to 5 months after loading and no patients dropped out


InterventionsComparison 1: short implants without augmentation versus long implants with augmentation

4 to 8 5 to 8.5 mm long implants versus 4 to 8 11.5 mm or longer implants placed in sinuses and maxillae of totally edentulous patients augmented with particulated autogenous bone from the iliac crest via lateral windows and, if necessary with onlay blocks 4 months prior to implant placement. The maxillary windows and the bone blocks were covered with 30 x 40 mm synthetic resorbable barriers (Inion GTR Biodegradable Membrane System, Tampere, Finland). Augmentation procedures were performed under general anaesthesia. Implants were left to heal submerged for 4 months. ExFeel and Rescue implants (MegaGen Implant Co. Lld., Gyeongbuk, South Korea) with external hexagon connections were used. Either overdentures or fixed provisional screw-retained reinforced resin prostheses were placed. The latter were replaced after 4 months by fixed definitive screw-retained metal-resin prostheses


OutcomesProsthesis and implant failures, complications, peri-implant marginal bone levels, patient satisfaction


Notes


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Low riskArticle: "A computer generated restricted randomisation list was created"

Allocation concealment (selection bias)Low riskArticle: "Only one of the investigators (ME), not involved in the selection and treatment of the patients, was aware of the randomisation sequence and could have access to the randomisation list stored in his pass-word protected portable computer.The randomised codes were enclosed in sequentially numbered, identical, opaque, sealed envelopes. Envelopes were opened sequentially after eligible patients signed the informed consent form to be enrolled in the trial. Therefore, treatment allocation was concealed to the investigators in charge of enrolling and treating the patients"

Blinding of outcome assessment (detection bias)
All outcomes
Low riskArticle: "One dentist (ES) not involved in the treatment of the patients performed all clinical assessments without knowing group allocation, therefore the outcome assessor was blinded"

Incomplete outcome data (attrition bias)
All outcomes
Low riskAll data presented, 1 drop-out

Selective reporting (reporting bias)Low riskAll planned outcomes were reported

Other biasLow riskNone apparent

Felice 2012

MethodsRandomised trial of parallel group design, 1 year post-loading follow-up. 1 patient, from the maxillary augmented group, dropped out before the 1 year follow-up because she did not want to continue the follow-up at the dental practice


ParticipantsPatients having 4 to 6 mm of alveolar bone height with a thickness of 6 mm or more below the sinus. Adults treated in dental hospitals/university clinics and private practices in Bologna, Roma and Chieti, Italy. Exclusion criteria were: general contraindications to implant surgery, patients irradiated in the head and neck area, immunosuppressed or immunocompromised patients, patients who took or are taking bisphosphonates intravenously, patients with untreated periodontitis, poor oral hygiene and motivation, uncontrolled diabetes, pregnancy or lactation, addiction to alcohol or drugs, psychiatric problems, lack of opposite occluding dentition in the area intended for implant placement, patients with an acute or chronic infection inflammation in the area intended for implant placement. 20 patients were treated in each group


InterventionsComparison 1: short implants without augmentation versus long implants with augmentation

1 to 3 5 mm long implants of 5 mm in diameter versus 1 to 3 10 mm or longer implants of 5 mm in diameter placed in 1-stage laterally augmented sinuses using a 1 cc sterile syringe of a sticky paste of made of 600-1000 micron pre-hydrated collagenated cortico-cancellous bone granules of porcine origin, mixed with OsteoBiol Gel 0 (mp3, OsteoBiol, Tecnoss Dental, Pianezza, TO, Italy) with their lateral windows sealed with a resorbable collagen membrane from equine pericardium (Evolution, Fine 30 x 30 mm, OsteoBiol) simultaneously to implant placement. Augmentation procedures were performed under local anaesthesia and implants were left to heal submerged for 4 months. ExFeel implants (MegaGen Implant Co. Lld., Gyeongbuk, South Korea), with external hexagon connection and a nanostructured calcium-incorporated titanium surface (Xpeed), were used. Provisional screw-retained reinforced resin prostheses were replaced after 4 months by definitive screw-retained or provisionally cemented metal-ceramic prostheses


OutcomesProsthesis and implant failures, complications, and peri-implant marginal bone levels


Notes


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Low riskArticle: "A computer generated restricted random list was created"

Allocation concealment (selection bias)Low riskArticle: "Only one of the investigators (Marco Esposito), not involved in the selection and treatment of the patients, was aware of the random sequence and could have access to the random list stored in his pass-word protected portable computer. The information on how to treat each patient was enclosed in sequentially numbered, identical, opaque, sealed envelopes. Envelopes were opened sequentially after the patients signed the informed consent accepting to participate into the trial. Therefore, treatment allocation was concealed to the investigators in charge of enrolling and treating the patients"

Blinding of outcome assessment (detection bias)
All outcomes
Low riskArticle: "Two dentists (Dr Laura Piana and Dr Daniele Panetta) not involved in the treatment of the patients performed all clinical measurements without knowing group allocation...."

Incomplete outcome data (attrition bias)
All outcomes
Low riskAll data presented, 1 drop-out

Selective reporting (reporting bias)Low riskAll planned outcomes were reported

Other biasLow riskNone apparent

Felice 2013

MethodsRandomised trial of parallel group design, 1 year post-loading follow-up. 2 patients dropped out from the 1-stage group just after augmentation: 1 never come back for unknown reasons and the other because of financial reasons


ParticipantsPatients having 1 to 3 mm of alveolar bone height with a thickness of 5 mm or more below the sinus. Adults treated in dental hospitals/university clinics and private practices in Bologna, Roma and Chieti, Italy. Exclusion criteria were: general contraindications to implant surgery, subjected to irradiation in the head and neck area, immunosuppressed or immunocompromised, treated or under treatment with intravenous amino-bisphosphonates, untreated periodontitis, poor oral hygiene and motivation, uncontrolled diabetes, pregnant or nursing, substance abusers, psychiatric problems or unrealistic expectations, lack of opposite occluding dentition/prosthesis in the area intended for implant placement, acute chronic infection/inflammation (sinusitis) in the area intended for implant placement, patients participating in other trials, if the present protocol could not be properly followed, referred only for implant placement or unable to attend a 5-year follow-up

30 patients were treated in each group, followed up to 1 year after loading


Interventions1-stage with simultaneous implant placement versus a 2-stage lateral window sinus lift procedure with implant placement delayed by 4 months using a bone substitute (Bio-Oss, Geistlich Pharmaceutical, Wolhusen, Switzerland). All patients were treated under local anaesthesia and the lateral sinus windows were sealed with resorbable collagen barriers (Bio-Gide, Geistlich). 1 to 3, 11 to 15 mm long, tapered Way Milano implants (Geass, Pozzuolo del Friuli, UD, Italy) with microtextured surface treated with laser (Synthegra) and conical internal hexagonal connection were submerged for 4 months, loaded with reinforced provisional prostheses which were replaced, after 4 months, by definitive metal-ceramic or zirconia restorations, rigidly joining the implants by being either provisionally cemented or screw-retained


OutcomesAugmentation, prosthesis and implant failures, complications, and peri-implant marginal bone level changes on periapical radiographs


Notes


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Low riskArticle: "3 computer generated restricted randomisation lists were created. Only 1 of the investigators (Marco Esposito), not involved in the selection and treatment of the patients, was aware of the random sequence and could have access to the randomisation lists stored in his pass-word protected portable computer"

Allocation concealment (selection bias)Low riskArticle: "The random codes were enclosed in sequentially numbered, identical, opaque, sealed envelopes. Envelopes were opened sequentially after the sinus lining epithelium of was lifted, therefore, treatment allocation was concealed to the investigators in charge of enrolling and treating the patients"

Blinding of outcome assessment (detection bias)
All outcomes
Low riskArticle: "One dentist (Gerardo Pellegrino), not involved in the treatment of the patients, made all clinical assessments without knowing group allocation, therefore outcome assessor was blind"

Incomplete outcome data (attrition bias)
All outcomes
Low riskAll data presented, 2 drop-outs

Selective reporting (reporting bias)Low riskAll planned outcomes were reported

Other biasLow riskNone apparent

Hallman 2002

MethodsRandomised, split-mouth study, 1 year post-loading follow-up. No withdrawals


ParticipantsPatients having less than 5 mm of alveolar bone in the floor of the sinus. Adults treated at the Gävla Hospital, Gävla, Sweden. No specific exclusion criteria were given (unhealthy, systemic or local contraindications such as undergoing radiation therapy). 11 patients were treated in the split-mouth study and 10 in the preference group


Interventions2-stage sinus lift with autogenous particulate bone from the mandibular ramus versus 2-stage sinus lift with a mixture of 80% of bovine anorganic bone (Bio-Oss) and 20% of particulate bone from the mandibular ramus left to heal for 6 months. A fibrin glue (Tisseel Duo Quick, Immuno, Wien, Austria) was added to the grafts after thrombin (Thrombin, Immuno). Procedures were performed under local anaesthesia and oral sedation. All implants were turned titanium self tapping (Nobel Biocare, Göteborg, Sweden): Mark II type implants were used in the former 2 groups and Mark III in the latter. All patients were rehabilitated with screw-retained metal-ceramic fixed prostheses

A third group (not part of this review) was composed by patients who refused to provide autogenous bone but accepted the treatment with a 2-stage sinus lift with 100% Bio-Oss


OutcomesProsthesis and implant failures, complications at augmented and donor sites; histomorphometry


Notes


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Low riskArticle: No information presented

Author's reply: "The randomization was done by a third party as a lottery. In an envelope there were 12 papers with either 6 possibilities for the mixture to be on the left side or the right side. Each patient was allotted by picking up one paper which said mixture on the left or right side"

Allocation concealment (selection bias)Low riskArticle: No information presented

Author's reply: "The surgeon knew the outcome of the surgery at the time of surgery just before making the incision"

Blinding of outcome assessment (detection bias)
All outcomes
High riskArticle: No information presented

Author's reply: "The study was not blinded"

Incomplete outcome data (attrition bias)
All outcomes
Low riskAll data presented, no drop-outs

Selective reporting (reporting bias)Low riskAll planned outcomes apparently reported

Other biasLow riskNone apparent

Lindgren 2012

MethodsRandomised, split-mouth study, 3-year post-loading follow-up. No withdrawals


ParticipantsCompletelly or partially edentulous patients in the maxilla with less than 5 mm of residual bone in the floor of the maxillary sinus and a crest width of at least 4 mm. Adults treated at the department of Oral and Maxillofacial Surgery, Public Health Service, Gävle, Sweden. Patients were excluded if they any severe disease or smoked more than 10 cigarettes/day. 11 patients were treated


Interventions2-stage lateral window sinus lift with granular bone substitutes: anorganic bovine bone (Bio-Oss®, Geistlich, Biomaterials, Wolhusen, Switzerland, particle diameters 0.25 to 1 mm) versus synthetic biphasic calcium phosphate consisting of 60% hydroxyapatite (HA) and 40% tricalcium phosphate (TCP) (Bone-Ceramic, Straumann® Basel, Switzerland, particle diameters 0.5 to 1 mm) left to heal for 8 months in a split-mouth trial. Lateral windows were sealed with resorbable collagen barriers (BioGide®, Geistlich). Implants were inserted into the healed graft of each side and were left to heal for an additional 4 months. All the augmentation procedures were performed under local anaesthesia. All implants were non-submerge SLActive surface (Straumann®) which were rehabilitated with cross-arch or partial fixed implant-supported prostheses


OutcomesProsthesis, implant and augmentation failures, complications (selectively reported), radiographic stability of bone height gain on panoramic radiographs, histomorphometry, peri-implant marginal bone level changes on peri-apical radiographs, plaque index (PLI), bleeding on probing (BPI), sulcus bleeding index (SBI), and probing pocket depth (PPD)


Notes


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Unclear riskArticle: No information presented

Unclear reply to letter

Allocation concealment (selection bias)Low riskArticle: "The randomization envelope was opened after the sinus membrane was elevated"

Blinding of outcome assessment (detection bias)
All outcomes
High riskArticle: No information presented

Authors' answer: "Outcome assessors not blinded"

Incomplete outcome data (attrition bias)
All outcomes
Low riskNo drop-out

Selective reporting (reporting bias)Low riskFull data of complications not provided

Authors's provided the missing information

Other biasLow riskAppropriate analysis for split-mouth study. None apparent

Merli 2013

MethodsRandomised trial of parallel group design, 6-month post-loading follow-up. 1 drop-out from the autogenous bone group because patient moved to another country


ParticipantsPartially edentulous patients in the maxilla with 1 to 3 mm of residual bone in the floor of the maxillary sinus. Adults treated in a private practice in Rimini, Italy. Patients were excluded if there were general contraindications to implant surgery, irradiated in the head and neck area, poor oral hygiene (full mouth plaque score and full mouth bleeding score ≥ 20%) and lack of motivation, uncontrolled diabetes, metabolic disease and drugs affecting bone remodeling, pregnancy and lactating period, substance abusers, smoking more than 20 cigarettes per day. 20 patients were treated in each group


Interventions1-stage lateral window sinus lift with particulated autogenous bone harvested from the mandibular ramus versus granules of anorganic bovine bone (Bio-Oss). The windows were sealed with resorbable collagen barriers (Bio-Gide). Implants were left to heal submerged for 8 months. All the augmentation procedures were performed under conscious sedation and local anaesthesia. All implants were titanium Nobel Speedy Groovy or MK IV implants (Nobel Biocare AG, Kloten, Switzerland) with oxidised surfaces (TiUnite) and were rehabilitated with provisional implant-supported prostheses replaced, after 6 months, by metal-ceramic screwed partial fixed prostheses


OutcomesProsthesis, implant and augmentation failures, complications, radiographic stability of bone height gain and peri-implant marginal bone level changes on periapical radiographs, chair-time from local anaesthesia administration to last suture placement, post-operative pain with a visual analogue scale and analgesic intake for 6 post-operative days


Notes


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Low riskArticle: "An investigator (LF), not involved in the selection and treatment of the patients, randomly assigned participants following simple randomization procedures (computerised random numbers) to 1 of 2 treatment groups"

Allocation concealment (selection bias)Low riskArticle: "The randomised codes were enclosed in sequentially numbered, identical, opaque, sealed envelopes. Envelopes were opened sequentially only after the sinus membrane was elevated. Therefore, treatment allocation was concealed to the investigator in charge of enrolling and treating the patients included in the trial"

Blinding of outcome assessment (detection bias)
All outcomes
High riskArticle: "While both the patients and the surgeon were aware of the allocated arm, the radiographic outcome examiner (GM) was unaware of the aim of the study and blinded to group allocation although Bio-Oss is usually more radiopaque than bone and can be recognized on radiographs. Implant failure and complications were assessed by an independent examiner (Moscatelli M.), who was not blinded to the intervention. Some complications, such as perforation of the sinus membrane, could occur during the surgical phase. The clinical examiner was present during surgery to register any complications, hence he was aware of the treatment administered"

Incomplete outcome data (attrition bias)
All outcomes
Low riskAll data presented, 1 drop-out

Selective reporting (reporting bias)Low riskAll planned outcomes apparently reported

Other biasLow riskNone apparent

Raghoebar 2005

MethodsRandomised, split-mouth study, 2-year post-loading follow-up. No withdrawals


ParticipantsPatients with severely resorbed fully edentulous maxillae and reduced stability and retention of the upper dentures. Adults treated at the University Hospital Groningen, the Netherlands. Patients were excluded if were edentulous for a period less than 1 year, history of irradiation in the head and neck area, history of reconstructive pre-prosthetic surgery or previous implant surgery. 5 patients were treated


Interventions2-stage lateral window sinus lift with autogenous blocks and particulate bone together with buccal onlays monocortico-cancellous bone grafts, to reconstruct the width of the maxilla, fixed with titanium screws harvested from the iliac crest with or without PRP left to heal for 3 months in a split-mouth trial. Barriers were not used. PRP was made using the Platelet Concentration Collection System kit (PCCS kit, 3i Implant Innovations Inc. Palm Beach Gardens, FL, USA). 54 ml of blood were mixed with 6 ml of anticoagulant (citrate dextrose) and processed with the platelet concentration system. To promote the release of growth factors from the platelets, 10% calcium chloride solution and the patient's serum, as a source of autologous thrombin, were added before actual reconstruction of the defect with the bone graft. The resulting gel was mixed with the bone graft and some gel was applied at the closure of the wound at the side treated with PRP. 3 implants were inserted into the healed graft of each side and were left to heal for an additional 6 months. All the augmentation procedures were performed under general anaesthesia. Surgical templates were used to optimise implant insertion. All implants were turned titanium self tapping (Nobel Biocare, Göteborg, Sweden) and were rehabilitated with 2 implant-supported prostheses


OutcomesProsthesis, implant and graft failures, complications and histomorphometric evaluation


Notes


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Low riskArticle: No information presented

Author's reply: "Randomisation by lot"

Allocation concealment (selection bias)Unclear riskArticle: No information presented

Author's reply failed to clarify the issue

Blinding of outcome assessment (detection bias)
All outcomes
Low riskArticle: "The investigators were blinded for both the clinical and laboratory investigations with regard to the PRP-treated side"

Incomplete outcome data (attrition bias)
All outcomes
Low riskAll data presented, no drop-outs

Selective reporting (reporting bias)Low riskAll planned outcomes apparently reported

Other biasUnclear riskIn all patients additional buccal onlays were performed meaning that these patients might have not been the ideal candidates for the hypothesis tested. It is therefore more difficult to interpret the results since the role of the additional buccal onlays on the final outcome cannot be quantified

Rickert 2013

MethodsRandomised, split-mouth study, 1 year post-loading follow-up. No withdrawals


ParticipantsPatients with severely resorbed fully edentulous maxillae and reduced stability and retention of the upper dentures. Adults treated at the University Hospital Groningen, the Netherlands. Patients were excluded if were edentulous for a period less than 1 year, history of irradiation in the head and neck area, history of reconstructive pre-prosthetic surgery or previous implant surgery, pathology in the maxillary sinuses. 36 patients were treated


Interventions2-stage lateral window sinus lift with autogenous particulate bone together with buccal onlays monocortico-cancellous bone blocks, to increase the width of the maxilla, fixed with titanium screws, harvested from the iliac crest left to heal for 3 to 4 months. The bilateral windows were opened following randomisation using rotative instruments of piezosurgery (Piezosurgery, Mectron Medical Technology Spa, Carasco, Genoa, Italy). In addition patients' sides were randomly allocated to received or not resorbable collagen membranes (Bio-Gide®, Geistlich Pharma AG, Wolhusen, Switzerland) over the grafts. All augmentation procedures were performed under general anaesthesia. 4 to 6 non-submerged 1-piece titanium implants (ITI®, Dental Implant System,Institut Straumann, Waldenburg, Switzerland) were inserted and left to heal for an additional 3 months. Patients were rehabilitated with implant-supported overdentures


OutcomesProsthesis, implant and graft failures, complications, time required to open the lateral window, changes over times of the maxillary bone width


Notes


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Unclear riskNo information in the text and no reply to answer

Allocation concealment (selection bias)Unclear riskArticle: "Randomly, by envelopes, one side was treated with conventional rotative instruments .... and the other side with piezosurgery"

Authors' reply: "We used envelopes with the operative procedures to randomize. The surgeon had to draw a envelope and had to treat the patient according to the procedure within that envelope"

Blinding of outcome assessment (detection bias)
All outcomes
Low riskArticle: "Clinically, all patients were evaluated according to a standardized protocol 1, 3, 6, and 12 weeks after surgery by a clinical research not knowing which procedure had been performed at a particular site"

Incomplete outcome data (attrition bias)
All outcomes
Low riskIn the article bone dehiscence at implant placement were not described by study group and it was unclear whether all complications were reported. The authors clarified the data after request of information

Selective reporting (reporting bias)Low riskDrop-outs, if any, were not specified in the article but the authors replied that no drop-outs occurred

Other biasHigh riskSplit-mouth study and pairing of data not taken into account

Si 2013

MethodsRandomised trial of parallel group design, 2-year and half post-loading follow-up. 1 drop-out from the augmentation group because of death and 3 patients excluded because of sinus epithelium perforation, 1 from the augmented group and 2 from the non-augmented group. These latter 3 patients were accounted for as failures


ParticipantsPatients having 2 to 8 mm of bone height below the maxillary sinus. Adult treated at the Department of Oral and Maxillofacial Implantology, Shanghai 9th People's Hospital, Shanghai Jiaotong University, China. Exclusion criteria were uncontrolled diabetes mellitus or other systemic disorders, untreated periodontal disease, endodontic lesions or other oral disorders, heavy smokers (> 10 cigarettes per day), rhinitis or sinusitis, insufficient residual bone quality to achieve implant stability, and previous implant installation or bone grafting at the surgical site. 45 patients were treated, 23 in the augmented group and 22 in the non-augmented group


Interventions1-stage crestal sinus lift procedure with osteotomes with or without granular Bio-Oss. Implants left to heal for 6 months. Straumann SLA (Waldenburg, Switzerland) implants were used


OutcomesProsthesis, implant and augmentation failures, radiographic bone gain and peri-implant marginal bone levels


Notes


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Low riskArticle: "Patients eligible for this study were assigned to two groups using the random numbers table (Complete randomization) by an assistant"

Allocation concealment (selection bias)Low riskArticle: "The assignment was concealed from the clinical operators until the sealed, numbered envelopes were opened before OSFE application during implant surgery"

Blinding of outcome assessment (detection bias)
All outcomes
Low riskArticle: "The outcome examiners and the patients were kept blinded to the assignment"

Incomplete outcome data (attrition bias)
All outcomes
High riskArticle: "Any patient with membrane perforation was excluded from this study"

3 patients were actually excluded and the outcome of the therapy remains unknown, but we counted them as failures

Selective reporting (reporting bias)High riskData on complications not presented and no reply to letter

Other biasLow riskNone apparent

Torres 2009

MethodsRandomised hybrid study design combining patients with a split-mouth study design with patients treated according to a quasi-random parallel group design with follow-up to 2 years after loading. No withdrawals


ParticipantsPatients having less than 7 mm of alveolar bone at the floor of the sinus. Adults treated at private clinic in Madrid, Spain. Exclusion criteria were severe systemic diseases (ASA score 3 or more), a previous history of chronic sinusitis. 57 patients were treated


Interventions1- or 2-stage sinus lift procedures using a lateral window technique and 100% granular Bio-Oss with or without PRP, left to heal for 6 months. Patients having up to 4 mm of residual bone height were augmented first and implant were placed after 6 months whereas patients with residual bone more than 4 mm up to 7 mm received implants during the sinus lift procedures. Implants were left to heal unloaded for 6 months. 10 to 20 cc of venous blood were collected 30 minutes prior to the surgery and mixed with a 3.8% sodium citrate solution at a 5/1 ratio, achieving anticoagulation through calcium binding. The blood was then centrifuged into 3 and separated into 3 layers: red blood cells (RBCs), PRP and poor plasma. Flow cytometry was used for platelet counting. Platelets counts were 2.97 + 0.7-fold over peripheral blood. PRP was activated with 30% CaCl2 solution and a PRP gel was obtained and mixed with Bio-Oss. The entire bone of the buccal window was removed, and after the sinus was filled with the bone substitute no barrier was used to seal the windows. Patients were instructed not to wear their upper dentures for 2-3 weeks after surgery. Osseotite (Biomet 3I, Palm Beach, FL, USA) implants were used


OutcomesProsthetic and implant failures, complications, and histomorphometric evaluation


Notes


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Low riskArticle: "..randomized sequence was performed by a computerized random number generated using GraphPadQuickCalc software (GraphPad Software Inc., La Joya, Ca, USA), including the concealment of the allocation schedule until the assignment was done"

Allocation concealment (selection bias)Low riskArticle: "Patients included in the inter-patient clinical trial were allocated by a blinded assistant into two groups: the first was to be treated with ABB alone, and the second with ABB + PRP"

Blinding of outcome assessment (detection bias)
All outcomes
Low riskArticle: "The surgeon was blinded to the graft material applied to each patient before graft implantation. An assistant handled PRP-ABB or the ABB group after the surgeon had already accessed the sinus and elevated membrane. The histologist was blinded to the samples' groups throughout the histomorphometric analysis"

Author's reply: "Implant stability was assessed manually with removed prostheses and mobile implants were considered as failures and this evaluation was done by a prosthodontist who was not aware of study groups"

Incomplete outcome data (attrition bias)
All outcomes
Low riskWe could only evaluate those data kindly provided by the authors

Selective reporting (reporting bias)Low riskAll planned outcomes apparently reported

Other biasHigh riskA mixed split-mouth and parallel group design was used: patients requiring augmentation at bilateral sinuses were randomised in a split-mouth study design whereas those requiring unilateral sinus lift sinus were alternated in a quasi-random study design. We have not included data from the quasi-random study

Torres 2013

MethodsRandomised study design having 106 patients treated according to a parallel group study design and 5 patients according to a split-mouth study design (not considered in the present review) with 1 year follow-up after loading. 2 withdrawals from the membrane group because moved to another city


ParticipantsPatients having less than 7 mm of alveolar bone at the floor of the sinus. Adults treated at private clinic in Madrid, Spain. Exclusion criteria were patients with severe systemic disease (American Society of Anaesthesiology III or IV), previous history of chronic sinusitis, pregnant, diseases affecting bone, such as osteomalacia, Paget's disease, vitamin D deficiency, hyperthyroidism, cancer (excluding non-melanoma skin cancer), alcoholism, those on corticosteroids, antiepileptic drugs, bisphosphonates, who had a perforation of the Schneiderian membrane. 106 patients treated, 55 without membranes and 51 with membranes


InterventionsThe sinus floor augmentation was made using as graft material (Bio-Oss; Geistlich Pharmaceutical AG, Wolhusen, Switzerland) via a lateral window. No membranes were used to cover the antrostomy defect in the experimental sites while in the control sites a resorbable porcine derived-collagen membrane was placed (Bio- Gide; GeitlishPharma, Wolhusen, Switzerland). The membrane was extended 2–3 mm beyond the antrostomy borders and stabilized with tacks. When residual bone height was ≥ 4 mm, implants were placed simultaneously to sinus augmentation, otherwise, delayed placements were conducted 6 months after graft surgery. Implants were surgically exposed 6 months after placement, and restored with a fixed implant-supported prosthesis or bar for retention of a removable prosthesis


OutcomesProsthetic and implant failures, selected complications, and selected histomorphometric evaluation


Notes


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Low riskArticle: "Patients or sites were allocated to intervention groups in a randomized sequence using a computer generated random number (GraphPad Software Inc., La Joya, CA, USA)"

Allocation concealment (selection bias)Low riskArticle: "All surgeries were performed by the same surgeon, who was blinded to group allocation until the last step of the surgery (closure of antrostomy defect)"

Blinding of outcome assessment (detection bias)
All outcomes
Low riskArticle: "Evaluations were performed by the same prosthodontist who was blinded to group allocation throughout the restorative treatment. Patients were also blinded to group allocation"

Incomplete outcome data (attrition bias)
All outcomes
Low riskThe authors informed as that 2 patients from the membrane group moved to another town

Selective reporting (reporting bias)High riskFull data of complications not provided. Patients with perforations of the sinus epithelium the apparently were excluded from the study

Other biasLow riskNone apparent

Wannfors 2000

MethodsRandomised trial of parallel group design, 3-year post-loading follow-up. No withdrawals at 3 years though 3 patients in the 1-stage group refused consent to remove the prostheses for testing implant stability


ParticipantsEdentulous patients with more than 2 mm but less than 7 mm of residual bone under the maxillary sinuses. Adults treated under general anaesthesia at the Karolinska Hospital, Stockholm, Sweden. Patients were included if they were edentulous in the upper jaw. Patients were excluded if they were older than 80 years, had pathologies in the maxillary sinus, had bone diseases or took medications known to effect bone metabolism (i.e. corticosteroids and bisphosphonates). 40 patients enrolled, 20 in each group


Interventions1-stage sinus lift with monocortical iliac bone blocks fixed usually with 2 implants left to heal for 6 months versus 2-stage sinus lift with particulate bone from the iliac crest left to heal for 6 months and then usually 2 implants were inserted into the healed graft and were left to heal for an additional 6 months. All implants were titanium self tapping (Brånemark System, Nobel Biocare)


OutcomesProsthesis failures, implant failures and marginal bone level changes on intraoral radiographs taken with a paralleling technique at abutment connection, 1 and 3 years. Intraoperative sinus membrane perforations


Notes


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Unclear riskArticle: "He (patient) was allotted to one of the two treatments according to a previously designed scheme by a third person"

Author's reply: "The randomization was performed by a third person without any beforehand contact with the patients"

Allocation concealment (selection bias)Unclear riskArticle: No information presented

Author's reply failed to clarify the issue

Blinding of outcome assessment (detection bias)
All outcomes
High riskArticle: No information presented

Author's reply: "The outcome assessor had knowledge of the randomized group, however not when assessing the x-ray data"

Incomplete outcome data (attrition bias)
All outcomes
Low riskNo withdrawals at 3 years

Selective reporting (reporting bias)High riskFull data of complications not provided

Other biasLow riskNone apparent

 
Characteristics of excluded studies [ordered by study ID]

StudyReason for exclusion

Aimetti 2008The article presented data from 4 patients treated following a split-mouth design. Authors informed us that they actually treated 16 patients. We are unable to present the data for the remaining 12 patients

Badr 2010Insufficient follow-up time (up to abutment connection), implants were not put even in function

Barone 2005No clinical outcome measures related to implant treatment

Barone 2008Insufficient follow-up time with no clinical outcome measures related to implant treatment

Barone 2013No clinical outcome measures related to implant treatment

Bensaha 2011Insufficient follow-up time (up to implant placement), implants were not even put in function

Bettega 2009Insufficient follow-up time (up to abutment connection), implants were not even put in function

Borges 2011Insufficient follow-up time (up to abutment connection), implants were not even put in function

Boyne 2005Described as RCT, unclear number of patients, unequal number of patients in the treatment groups. No reply to letter

Canullo 2009No clinical outcome measures related to implant treatment

Choi 2009No clinical outcome measures related to implant treatment

Consolo 2007No clinical outcome measures related to implant treatment

Cordaro 2008No clinical outcome measures related to implant treatment

Corinaldesi 2013No clinical outcome measures related to implant treatment

Crespi 2009No clinical outcome measures related to implant treatment

Froum 1998Described as RCT, unclear number of patients and tested interventions which seem to be much more than 8, unequal number of patients in the treatment groups. No reply to letter

Froum 2006No clinical outcome measures related to implant treatment

Froum 2008No clinical outcome measures related to implant treatment

Froum 2013No clinical outcomes useful for the review and too short follow-up (study terminated before implant placement)

Gassling 2013Insufficient follow-up time (up to abutment connection), implants were not put even in function

Ghanaati 2014Trial is a CCT, not an RCT

Hallman 2008No clinical outcome measures related to implant treatment

Hermund 2012Insufficient follow-up time (up to abutment connection), implants were not even put in function

Kassolis 2005No clinical outcome measures related to implant treatment

Khairy 2013Insufficient follow-up time (up to abutment connection), implants were not put even in function

Kim 2009No clinical outcome measures related to implant treatment

Kock 2010Insufficient follow-up time (possibly up to initial prosthetic loading)

Kühl 2012No clinical outcomes useful for the review and too short follow-up (study terminated before implant placement)

Kühl 2013No clinical outcome measures related to implant treatment

Mangano 2007The authors informed us that the trial was not an RCT but a CCT

Payer 2013No clinical outcome measures related to implant treatment

Pikdöken 2011No clinical outcome measures related to implant treatment

Sammartino 2011Insufficient follow-up time (up to a couple of days after implant placements), implants were not even put in function

Schaaf 2008Insufficient follow-up time (up to abutment connection), implants were not even put in function

Silvestri 2013Insufficient follow-up time (up to abutment connection), implants were not even put in function

Steigmann 2005No clinical outcome measures related to implant treatment

Suba 2006No clinical outcome measures related to implant treatment

Szabó 2005Insufficient follow-up time (up to abutment connection), implants were not even put in function

Tawil 2001Inappropriate study design, neither parallel group nor split-mouth

Testori 2013No clinical outcome measures related to implant treatment

Triplett 2009Unclear how many patients were randomised to each group, data very confused and we were unable to retrieve sufficient data from the original publication. No reply to letter

Trombelli 2012Insufficient follow-up time (up to 6 months after implant placement), implants were possibly loaded for a very short period

Wagner 2012Data presented in a way we could not use. No reply to letter

Yilmaz 2013No clinical outcome measures related to implant treatment

 
Comparison 1. Long implants with sinus lift versus short implants without augmentation

Outcome or subgroup titleNo. of studiesNo. of participantsStatistical methodEffect size

 1 Prosthesis failures 1 year3109Peto Odds Ratio (Peto, Fixed, 95% CI)0.37 [0.05, 2.68]

 2 Implant failures 1 year4137Peto Odds Ratio (Peto, Fixed, 95% CI)0.44 [0.10, 1.99]

 3 Complications 1 year4137Peto Odds Ratio (Peto, Fixed, 95% CI)4.77 [1.79, 12.71]

 
Comparison 2. Different sinus lift procedures

Outcome or subgroup titleNo. of studiesNo. of participantsStatistical methodEffect size

 1 Bone versus no bone graft2Odds Ratio (Fixed, 95% CI)Subtotals only

    1.1 Implant failures (1 year)
2Odds Ratio (Fixed, 95% CI)0.52 [0.10, 2.82]

 2 Bone versus no bone graft2Mean Difference (Fixed, 95% CI)2.89 [2.35, 3.43]

    2.1 Bone gain
2Mean Difference (Fixed, 95% CI)2.89 [2.35, 3.43]

 3 Autogenous bone versus bone substitute2Odds Ratio (Fixed, 95% CI)Subtotals only

    3.1 Implant failures
2Odds Ratio (Fixed, 95% CI)4.20 [0.81, 21.79]

 4 Autogenous bone or Bio-Oss +/- PRP2Odds Ratio (Fixed, 95% CI)Subtotals only

    4.1 Implant failures
2Odds Ratio (Fixed, 95% CI)1.40 [0.12, 16.52]

    4.2 Complications
2Odds Ratio (Fixed, 95% CI)0.88 [0.13, 6.09]

 
Summary of findings for the main comparison. Long implants with augmentation versus short implants without augmentation for replacing missing teeth

Long implants with augmentation versus short implants without augmentation for replacing missing teeth: augmentation procedures of the maxillary sinus

Patient or population: patients with replacing missing teeth
Settings: general and specialist dental practice
Intervention: sinus lift versus no sinus lift

OutcomesIllustrative comparative risks* (95% CI)Relative effect
(95% CI)
No of participants
(studies)
Quality of the evidence
(GRADE)
Comments

Assumed riskCorresponding risk

Short implantsLong implants with sinus lift

Prosthesis failures
subjective assessment
Follow-up: median 1 year
Study populationOR 0.37
(0.05 to 2.68)
109
(3 studies)
⊕⊕⊕⊝
moderate1

55 per 100021 per 1000
(3 to 134)

Moderate

50 per 100019 per 1000
(3 to 124)

Implant failures
Follow-up: median 1 year
Study populationOR 0.44
(0.1 to 1.99)
137
(4 studies)
⊕⊕⊕⊝
moderate1

71 per 100033 per 1000
(8 to 133)

Moderate

50 per 100023 per 1000
(5 to 95)

Complications
Follow-up: median 1 year
Study populationOR 4.77
(1.79 to 12.71)
137
(4 studies)
⊕⊕⊝⊝
low1,2

43 per 1000176 per 1000
(74 to 363)

Moderate

50 per 1000201 per 1000
(86 to 401)

*The basis for the assumed risk (e.g. the median control group risk across studies) is provided in footnotes. The corresponding risk (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI)
CI: confidence interval; OR: Peto odds ratio

GRADE Working Group grades of evidence
High quality: Further research is very unlikely to change our confidence in the estimate of effect
Moderate quality: Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate
Low quality: Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate
Very low quality: We are very uncertain about the estimate

 1 Downgraded for imprecision (small number of events)
2 Downgraded for inconsistency (statistical heterogeneity present P value = 0.04, I2= 64%)
 
Summary of findings 2. Different sinus lift procedures

Comparison between different sinus lift procedures

Patient or population: patients with insufficient bone below maxillary sinus

Settings: dental practice

Intervention: sinus lift procedure

Comparison: sinus lift procedure

OutcomesComments

Prosthesis failures

(at 5 months to 5 years)
Data for prosthetic failures were present for 5 comparisons (all only including 1 small study). There is insufficient evidence to conclude that 1 sinus lift procedure leads to fewer prosthetic failures than another. The comparisons for this outcome were: bone graft versus no bone graft, 2 different bone substitutes, 1- versus 2-stage lateral sinus lift, 2-stage granular bone versus 1-stage autogenous bone blocks, and crestal versus lateral sinus lift

Implant failures

(at 5 months to 5 years)
Data for implant failures were present for 8 comparisons (including 1 or 2 small studies). There is insufficient evidence to conclude that 1 sinus lift procedure leads to fewer implant failures than another. The comparisons for this outcome were: bone graft versus no bone graft, autogenous bone versus bone substitute, bone graft with or without platelet-rich plasma (PRP), 2 different bone substitutes, 1- versus 2-stage lateral sinus lift, 2-stage granular bone versus 1-stage autogenous bone blocks, crestal versus lateral sinus lift, and hand versus electric malleting for crestal sinus lifting

 
Table 1. Comparison of different sinus lift procedures

ComparisonOutcome DataEffect estimate (95% CI) P value

Rotary instruments versus piezosurgery

 

(Rickert 2013)

 

Split-mouth
Prosthesis failuresN = 36; noneN/A

Implant failuresN = 36; noneN/A

Augmentation procedure failureN = 36; noneN/A

Complications at augmented siteN = 36; both = 2, rotary only = 6, piezosurgery only = 6, neither = 22OR 1.00 (0.27 to 3.74) P = 1.00

Complications at donor siteN = 36; noneN/A

With versus without bone graft

 

(Felice 2009b)

 

Split-mouth
Prosthesis failuresN = 9; noneN/A

Implant failuresN = 9; 1 failure for withoutOR 3.35 (0.12 to 93.8) P = 0.48

Complications (1 year)N =9; both = 1, without = 2, with = 1, none = 5OR 0.50 (0.01 to 9.60) P = 1.00

Bone gain at 6 monthsN = 9MD 0.26 (-0.91 to 1.43) P = 0.65

With versus without bone graft

 

(Si 2013)

 

Parallel group
Prosthesis failures (1 year)With bone versus without bone

2/22 versus 3/22
OR 0.63 (0.10 to 4.22) P = 0.64

Implant failures (1 year)2/22 versus 3/22OR 0.63 (0.10 to 4.22) P = 0.64

Augmentation procedure failure (1 year)1/22 versus 2/22OR 0.48 (0.04 to 5.67) P = 0.56

Complications (1 year)Not reportedN/A

Bone gain at 6 monthsGraft N = 21 5.66 (SD 0.99) versus no graft N = 20 2.06 (1.01)MD 3.60 (2.99 to 4.21) P < 0.001

Bone gain at 18 monthsGraft N = 20 3.02 (SD 0.48) versus no graft N = 19 3.12 (0.70)MD -0.10 (-0.47 to 0.27) P = 0.60

Bone gain at 30 monthsGraft N = 20 3.17 (SD 1.95) versus no graft N = 19 3.07 (1.68)MD 0.10 (-1.04 to 1.24) P = 0.86

Autogenous bone versus bone substitute

 

(Hallman 2002)

 

Split-mouth
Implant failures (abutment connection)N = 11; 5/11 autogenous bone versus 2/11 80% Bio-Oss. Assume not bilateralOR 3.75 (0.54 to 26.04) P = 0.18

ComplicationsN = 11; noneN/A

Autogenous bone versus bone substitute

 

(Merli 2013)

 

Parallel group
Implant failures2/20 versus 0/20OR 5.54 (0.25 to 123.08) P = 0.28

Complications2/20 versus 1/20OR 2.11 (0.18 to 25.35) P = 0.56

Autogenous bone versus bone substitute

(Lindgren 2012)

Split-mouth
Prosthesis failures0/11 versus 0/11N/A

Implant failures1/11 versus 1/11OR 1.00 (0.05 to 18.30) P = 1.00

Augmentation procedure failure0/11 versus 0/11N/A

Complications at augmented siteN = 11; both = 0, Bio-Oss only = 1, different bone substitute only = 0, neither = 10OR 3.29 (0.12 to 89.8) P= 0.48

Autogenous bone ± PRP

 

(Raghoebar 2005)

 

Split-mouth
Prosthetic failuresN = 5; none N/A

Implant failuresN = 5; 1 failure in PRPOR 3.67 (0.12 to 113.73) P = 0.46

ComplicationsN =5; 1 occurred in non-PRPOR 0.27 (0.01 to 8.46) P = 0.46

Autogenous bone or Bio-Oss ± PRP

 

(Torres 2009)

 

Split-mouth
Implant failuresN = 57; both = 0, PRP only = 1, no PRP only = 2, neither = 54OR 0.50 (0.01 to 17.42) P = 0.71

ComplicationsN = 57; both = 0, PRP only = 3, no PRP only = 2, neither = 52OR 1.49 (0.15 to 15.07) P = 1.00

Partial graft loss

 
N = 57; both = 0, PRP only = 2, no PRP only = 3, neither = 52OR 1.5 (0.17 to 17.96) P = 1.00

(Stata exact OR)

Membrane versus no membrane to seal the lateral window

(Torres 2013)

Parallel group
Prosthetic failures9/51 versus 4/53OR 2.63 (0.75 to 9.14) P = 0.13

Implant failures9/51 versus 4/53OR 2.63 (0.75 to 9.14) P = 0.13

1-stage versus 2-stage

 

(Felice 2013)

 

Parallel group
Prosthesis failures1-stage versus 2-stage

0/28 versus 1/30
0.35 (0.01 to 6.83) P = 0.52

Implant failures (before loading)3/28 versus 1/30

 
OR 3.48 (0.34 to 35.61) P = 0.29

Complications 2/28 versus 1/30OR 2.23 (0.19 to 26.06) P = 0.52

1-stage block versus 2-stage particulate bone

 

(Wannfors 2000)

 

Parallel group
Prosthetic failures1/20 versus 1/20OR 1.00 (0.06 to 17.18) P = 1.00

Implant failures8/20 versus 6/20OR 1.56 (0.42 to 5.76) P = 0.51

Complications9/20 versus 10/20OR 0.82 (0.24 to 2.84) P = 0.75

Crestal versus lateral sinus lift

 

(Cannizzaro 2009)

 

Parallel group
Prosthetic failures1/20 versus 2/20OR 0.47 (0.04 to 5.69) P = 0.56

Implant failures1/20 versus 3/20OR 0.30 (0.03 to 3.15) P = 0.31

Graft failures0/20 versus 2/20OR 0.18 (0.01 to 4.01) P = 0.28

Complications at treated and donor sites (1 year)1/20 versus 4/20OR 0.21 (0.02 to 2.08) P = 0.18

Partial graft loss

 
2/20 versus 3/20OR 0.63 (0.09 to 4.24) P = 0.63

Mallet versus rotary

 

(Checchi 2010)

 

Split-mouth
Prosthetic failuresN = 12; noneN/A

Implant failuresN = 12; noneN/A

ComplicationsN = 12; 5/12 versus 1/12OR 7.86 (0.75 to 82.13) P = 0.09

Preference 5 months after loadingN = 15; 13 preferred rotary techniqueBinomial test P = 0.007

Hand mallet versus electric mallet

(Crespi 2012)

 

Parallel group

 

Followed for 19 months after loading
Prosthesis failuresHand mallet versus electric mallet

0/40 versus 0/40
N/A

Implant failures (before loading)1/40 versus 1/40

 
OR 1.00 (0.06 to 16.56) P = 1.00

Augmentation failures0/40 versus 0/40N/A

Complications at augmented site3/40 versus 0/40OR 3.16 (0.31 to 31.78) P = 0.33

Bone gainN = 40 4.17 (SD 1.70) versus N = 40 4.07 (SD 1.03)MD 0.10 (-0.52 to 0.72) P = 0.75

 Data on patients who dropped out removed from the table.
CI - confidence interval; MD - mean difference; OR - odds ratio; SD - standard deviation.