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Keywords:

  • Pregnancy;
  • periodontal disease;
  • oral health;
  • oral hygiene;
  • antenatal care providers

Abstract

  1. Top of page
  2. Abstract
  3. Introduction
  4. Methods
  5. Results
  6. Discussion
  7. Acknowledgements
  8. References

Background

The aim of this study was to explore the oral hygiene practices and oral health status of Italian postpartum women.

Methods

A self-administered questionnaire assessed socio-demographic information, oral hygiene habits and frequency of dental visits. All women received a thorough oral examination within five days after delivery. Logistic regression models were used to estimate odds ratios and 95% confidence intervals for exposures of interest and the presence of ‘severe’ periodontitis.

Results

Seven hundred and fifty women participated in the study; 99.1% brushed their teeth everyday and 59.9% visited the dentist annually. The mean frequency of sites with bleeding on probing was 16.1% and the median clinical attachment level was 2.1 mm. The mean caries experience score (DMFT) was 8. Severe periodontal disease was present in 21.9% of individuals. Patients who reported visiting a dentist only when in pain and women with three dental caries or more were significantly more likely to have periodontitis (OR: 1.6; 95% CI: 1.1–2.2; p < 0.05 and OR: 2.3; 95% CI: 1.5–3.5; p < 0.01, respectively).

Conclusions

Given the possible association between maternal and infant oral health, and between periodontal infection and general health, antenatal care providers should collaborate with dentists to encourage all pregnant women to comply with the oral health professionals' recommendations regarding appropriate dental brushing techniques and the importance of dental visits.


Abbreviations and acronyms
BOP

bleeding on probing

CAL

clinical attachment loss

CI

confidence intervals

DMFT

decayed, missing, filled tooth

OR

odds ratio

Introduction

  1. Top of page
  2. Abstract
  3. Introduction
  4. Methods
  5. Results
  6. Discussion
  7. Acknowledgements
  8. References

The oral changes that can occur in pregnancy have been a focus of interest for many years. Pregnant women experience several physiological changes that can adversely affect oral health. The elevation in oestrogen and progesterone enhances inflammatory response and consequently alters the gingival tissue.[1] Periodontal diseases and dental problems such as caries, erosion, loose teeth and pyogenic granulomas may have special significance during and after pregnancy.[2] Poor maternal oral health increases the risk of early transmission of cariogenic bacteria to women's offspring, thus increasing the risk of developing caries.[3] In addition, the possible association between periodontal disease and adverse pregnancy outcomes,[4, 5] such as preterm birth and low birthweight babies, cardiovascular disease,[6, 7] type II diabetes,[8, 9] kidney disease[10] and respiratory disease,[11] deserve attention even though data are still contradictory.

Good oral health care during pregnancy, infancy and childhood is essential. However, pregnant women, parents and caregivers of infants often receive little education about proper preventive oral and dental health care, including fluoride intake and dietary measures.[12] Pregnant women can achieve good oral health standards through proper diet, regular dental visits during pregnancy, professional cleaning, correct technique for toothbrushing and flossing, as well as any medically required dental work.[13]

Adequate oral hygiene habits are mandatory to control the development of periopathogenic oral biofilms which have been reported to be associated with poor obstetric outcomes.[4] As such, the aim of this study was to describe self-reported oral hygiene habits among a population of postpartum women in Italy and to examine the prevalence of oral diseases.

Methods

  1. Top of page
  2. Abstract
  3. Introduction
  4. Methods
  5. Results
  6. Discussion
  7. Acknowledgements
  8. References

The study sample consisted of 750 postpartum women who met the following eligibility criteria: (a) aged 18 or older; (b) weight >40 kg; (c) height >150 cm; (d) reported no multiple gestation; (e) no history of HIV or AIDS or autoimmune disease or diabetes; (f) no history of drug treatment during the past 12 months; (g) ≥20 natural teeth; and (h) no history of periodontal treatment in the previous six months.

Study intervention

Periodontal examiners were trained and calibrated to measure periodontal soft and hard tissue indices in both a dental chair and hospital bed. Examiners were masked from obstetric data. In-person interviews by dental hygienists were conducted to collect data on socio-demographic characteristics, smoking status, alcohol consumption, medical history and oral hygiene practices. This study was nested in a study on periodontal disease and adverse pregnancy association. Postpartum women were recruited from the postnatal ward of three Italian obstetric clinics (Milan, Rome, Sassari) by the dental hygienist of the hospital.[14] All participants gave written informed consent. Prior to commencing the study, the Italian Ministry of University and Research and the Scientific Committee of the Center for Fetal Research ‘Giorgio Pardi’ approved all study procedures.

Study protocol

Participants were asked to compile a standardized questionnaire and received a thorough dental and periodontal examination within five days after delivery. The questionnaire assessed socio-demographic characteristics, including age, country of birth, place of residence, education level, self-reported medical history, tobacco consumption and oral hygiene habits. The questionnaire required ˜15 minutes to complete and was self-administered. Oral hygiene habits such as time dedicated to toothbrushing (less than 1 minute, between 1 and 3 minutes, and more than 3 minutes), frequency of toothbrushing (never, 1–2 times/day or 3 times/day), and visits to a dentist (biennially, once a year, or when in pain) were assessed. Additional questions included information on self-reported oral symptoms during pregnancy (halitosis, gum bleeding, gum swelling and loose teeth).

The oral examination was performed at bedside by two trained and calibrated dental examiners under standardized conditions with a portable LED headlamp system, disposable mouth mirrors (Brillant, Hager & Werken, Duisburg-D), and sterile colour coded plastic periodontal probes with millimetre markings (Hawe Perio-Probe, Hawe-Neos Dental, Bioggio-CH). Several measures of dental and periodontal health were collected: gingival recession, gingival pocket depth, bleeding on probing (BOP), clinical attachment level (CAL), and Decay Missing Filled Tooth (DMFT). CAL was calculated as probing depth plus recession. DMFT index was recorded for each patient according to the guidelines of the World Health Organization.[15] BOP was expressed as the percentage of sites exhibiting this response. For the purpose of this analysis, periodontal involvement was categorized into three different levels: ‘healthy’ (all sites with CAL <4 mm), ‘mild’ (at least one site with CAL from 4 mm to 6 mm) and ‘severe’ (at least one site with CAL greater than or equal to 6 mm).

Statistical analysis

The distribution of the sociodemographic characteristics, smoking status and self-reported oral hygiene habits was evaluated. The mean number of sites with CAL, mean decayed, mean filled and mean missing teeth along with overall mean DMFT was calculated. Education was measured by the highest level of education achieved, which we described by three categories: (1) less than 8 years of school; (2) 9–13 years of school; and (3) having some college education or more (13 years or more of school).

Finally, we performed a multivariate logistic regression analysis to estimate odds ratios (ORs) and 95% confidence intervals (CI) for exposures of interest such as age, country of birth, area of residence, education, tobacco use, oral hygiene habits, dental visits frequency, dental decay and the presence of ‘severe’ and ‘mild’ periodontal disease. All p-values reported were considered to be statistically significant at p < 0.05. P-values for trend were obtained by assigning ordinal values to each category. Statistical analysis was performed using STATA, version 10.0 (Stata, College Station, TX, USA).

Results

  1. Top of page
  2. Abstract
  3. Introduction
  4. Methods
  5. Results
  6. Discussion
  7. Acknowledgements
  8. References

A total of 750 postpartum women were included in this analysis (Table 1). Women ranged in age from 18 to 45 years with a median age of 32 years (interquartile range 26–37 years). The majority of study participants were European (88.7%; 95% CI: 86.2–90.7). Around 62% (95% CI: 58.9–65.8) lived in an urbanized region, 23.3% (95% CI: 20.5–26.5) lived in a suburban area and 14.3% (95% CI: 11.9–16.9) were from a rural region. When education was considered, 29.8% (95% CI: 26.7–33.2) attended school for less than 8 years, 46.5% (95% CI: 43.0–50.1) had 9–13 years of schooling, and 23.7% (95% CI: 20.7–26.8) had some college education or more. The proportion of current smokers was 11.4% (95% CI: 9.3–13.8), former smokers 33.7% (95% CI: 30.4–37.2) and 54.9% (95% CI: 51.2–58.5) reported having never smoked.

Table 1. Socio-demographic characteristics of study participants by country
Socio-demographic CharacteristicsTotal (= 750)95% CI
n (%) 
  1. IQR = intra-quartile range.

  2. a

    Due to small sample size Africa, America, Asia and Australia were collapsed into ‘Other’ category.

Age
18–2470 (9.3)7.5–11.6
25–29141 (18.8)16.2–21.8
30–34279 (37.2)33.8–40.7
35–39205 (27.4)27.3–30.6
40–4555 (7.3)7.3–9.4
Median [IQR]32 [26–37] 
Country of birtha
Europe665 (88.7)86.2–90.7
Other85 (11.3)9.3–13.8
Place of residence
Rural107 (14.3)11.9–16.9
Suburban175 (23.3)20.5–26.5
Urban468 (62.4)58.9–65.8
Education (years)
Less than 8224 (29.8)26.7–33.2
9 to 13349 (46.5)43.0–50.1
13 or more177 (23.7)20.7–26.8
Smoking status
Never412 (54.9)51.3–58.5
Former253 (33.7)30.4–37.2
Current85 (11.4)9.3–13.8

Most women (99.1%) reported brushing their teeth everyday (Table 2). Among these subjects, 62.9% brushed three times a day, and 37.1% brushed their teeth up to two times per day. Nearly 78% of patients used toothbrush and toothpaste; 22.1% also used dental floss and mouthwash daily. Participants most frequently reported visiting the dentist annually (59.9%), although a relatively high proportion visited only when in pain (46.1%) and 4.1% went biennially.

Table 2. Oral hygiene habits in pregnancy
Oral hygiene habitsTotal (= 750)
n (%)
  1. a

    Indicates patients visiting a dentist only when in pain.

Everyday oral hygiene
No7 (0.9)
Yes743 (99.1)
Toothbrushing frequency
3 times/day467 (62.9)
Up to 2 times/day276 (37.1)
Never0 (0.0)
Oral hygiene techniques
Tooth brush + tooth paste584 (77.9)
Dental floss + mouthwash166 (22.1)
Daily time dedicated to teeth brushing (min)
<1 min163 (21.7)
1–3 min456 (60.8)
>3 min131 (17.5)
Dental visit frequency
Biennially31 (4.1)
Annually373 (49.8)
Paina346 (46.1)

When oral health was considered (Table 3), the mean number of teeth present was 25.7 (SD ± 3.1). The mean frequency of sites with BOP was 16.1% and the mean CAL was 2.2 mm. The mean DMFT score was 7.9 (SD ± 4.2). Specifically, the mean D was 1.5 (SD ± 2.2), M was 1.5 (SD ± 2.3) and F was 4.9 (SD ± 3.8). More than half of women had decayed teeth (51.7%). Severe periodontal disease was present in 21.9% of subjects and the rate of mild periodontal disease was 55.2%.

Table 3. Oral health in postpartum women
Oral healthTotal (= 750)
n (%)
  1. IQR = intra-quartile range; CAL = clinical attachment level; BOP = bleeding on probing; DMFT = Decay Missing Filled Tooth; SD = standard deviation.

  2. a

    All sites with CAL <4 mm.

  3. b

    At least one site with CAL 4–6 mm.

  4. c

    At least one site with CAL ≥6 mm.

Number of teeth
Median [IQR]27 [25–28]
Mean ± SD 25.7 ± 3.1
BOP
Median [IQR]5.2 [0.9–19.2]
Mean ± SD 16.1 ± 25.0
CAL
Median [IQR]2.1 [1.8–2.5]
Mean ± SD 2.2 ± 0.5
DMFT
Mean DMFT ± SD 7.9 ± 4.2
Mean D  ±  SD 1.5 ± 2.2
Mean M  ±  SD 1.5 ± 2.3
Mean F  ±  SD 4.9 ± 3.8
D388 (51.7)
M400 (53.3)
F645 (86.0)
Periodontal status
Healthya136 (22.9)
Mildb450 (55.2)
Severec164 (21.9)
Mean number of sites with CAL <4 mm ± SD99.2 ± 15.3
Mean number of sites with CAL ≥4 but <6 mm ± SD 6.8 ± 9.2
Mean number of sites with CAL ≥6 mm ± SD1.0 ± 4.1

Table 4 presents multivariate-unadjusted models for the association between severe and mild periodontal disease, socio-demographic information, oral health and oral hygiene practices. When severe periodontal disease was considered, women who received less than 8 years of education were at higher risk of having periodontal disease (OR: 2.0; 95% CI: 1.2–3.2; p < 0.01). Patients who reported visiting a dentist only when in pain were significantly more likely to have periodontitis (OR: 1.6; 95% CI: 1.1–2.2; p < 0.05). In addition, patients with three dental caries or more were twice as likely to have periodontal disease when compared to individuals with less decays (OR: 2.3; 95% CI 1.5–3.5; p < 0.01). No statistically significant associations were observed for the following variables: age, country of birth, place of residence, smoking status and oral hygiene habits.

Table 4. Multivariate analysis of the association between severe periodontal disease, socio-demographic characteristics and oral hygiene habits
 Severe periodontal diseaseaMild periodontal diseaseb
Yes (= 164)No (= 586)Odds Ratio (95% CI)P-value for trendYes (= 450)No (= 300)Odds Ratio (95%CI)P-value for trend
  1. a

    Severe periodontal disease was defined as having at least one site with CAL ≥6 mm.

  2. b

    Mild periodontal disease was defined as having at least one site with CAL from 4–6 mm.

  3. c

    Indicates patients visiting a dentist only when in pain.

Age
18–2413 (18.6)57 (81.4)1.0 39 (55.7)31 (44.3)1.0 
25–2935 (24.8)106 (75.2)1.4 (0.7–3.0)0.5081 (57.5)60 (42.5)1.1 (0.6–1.9)
30–3454 (19.4)225 (80.6)1.1 (0.5–2.1)174 (62.4)105 (37.6)1.3 (0.8–2.2)0.82
35–3951 (24.9)154 (75.1)1.5 (0.7–2.9)123 (60.0)82 (40.0)1.2 (0.7–2.1)
40–4511 (20.0)44 (80.0)1.1 (0.4–2.7)33 (60.0)22 (40.0)1.2 (0.6–2.5)
Country of birth
Europe145 (21.8)520 (78.2)1.00.91390 (58.7)275 (41.3)1.00.03
Other19 (22.4)66 (77.6)1.1 (0.6–1.8)60 (70.6)25 (29.4)1.7 (1.1–2.8)
Area
Rural22 (20.6)85 (79.4)1.00.4658 (54.2)49 (45.8)1.0 
Suburban33 (18.9)142 (81.1)0.9 (0.5–1.6)127 (72.6)48 (27.4)2.2 (1.3–3.7)<0.01
Urban109 (23.3)359 (76.7)1.2 (0.7–2.0)265 (56.6)203 (43.4)1.1 (0.7–1.7)
Education (years)
13 or more 66 (18.9)283 (81.1)1.0 221 (63.3)128 (36.7)1.0 
9 to 1360 (29.7)146 (82.5)0.5 (0.4–0.8)<0.01114 (64.4)63 (35.6)0.9 (0.7–1.4)<0.01
Less than 867 (29.9)157 (70.1)2.0 (1.2–3.2)115 (51.3)109 (48.7)0.6 (0.4–0.9)
Smoking status
Never91 (22.1)321 (77.9)1.0 252 (61.2)160 (38.8)1.0 
Former53 (20.9)200 (79.1)0.9 (0.6–1.4)0.87147 (58.1)106 (41.9)0.9 (0.6–1.2)0.74
Current20 (23.5)65 (76.5)1.1 (0.6–1.9)51 (60.0)34 (40.0)0.9 (0.6–1.5)
Everyday oral hygiene
Yes163 (21.9)580 (78.1)1.00.61446 (60.0)297 (40.0)1.00.88
No1 (14.3)6 (85.7)0.6 (0.1–4.9)4 (57.1)3 (42.9)0.9 (0.2–4.0)
Toothbrushing frequency
3 times/day102 (21.5)372 (78.5)1.00.07274 (57.8)200 (42.2)1.00.11
Up to 2 times/day62 (22.5)214 (77.5)1.5 (1.0–2.3)176 (63.8)100 (36.2)1.3 (0.9–1.7)
Daily time dedicated to toothbrushing (min)
<1 min41 (25.2)122 (74.8)1.0 93 (57.1)70 (42.9)1.0 
1–3 min95 (20.8)361 (79.2)0.8 (0.5–1.2)0.52282 (61.9)174 (38.1)1.2 (0.8–1.8)0.44
>3 min28 (21.4)103 (78.6)0.8 (0.5–1.4)75 (57.2)56 (42.8)1.1 (0.6–1.6)
Dental visit frequency
Annually 69 (18.5)304 (81.5)1.0 233 (62.5)140 (37.5)1.0 
Biennially5 (16.1)26 (83.9)0.9 (0.3–2.3)20 (64.5)11 (35.5)1.1 (0.5–2.3)0.28
Painc90 (26.0)256 (74.0)1.6 (1.1–2.2)<0.05197 (57.0)149 (43.0)0.8 (0.7–1.1)
Decays
060 (16.6)302 (83.4)1.0 229 (63.3)133 (36.7)1.0 
1–254 (23.9)172 (76.1)1.6 (1.1–2.4)<0.01132 (58.4)94 (41.6)0.8 (0.6–1.1)0.18
3 or more50 (30.9)112 (69.1)2.3 (1.5–3.5)89 (54.9)73 (45.1)0.7 (0.5–1.0)

When mild periodontal disease was considered, patients from other countries were significantly more likely to have mild periodontal disease when compared to Italian women. Also, patients from suburban areas or a lower education level were at lower risk of having mild periodontal disease.

Discussion

  1. Top of page
  2. Abstract
  3. Introduction
  4. Methods
  5. Results
  6. Discussion
  7. Acknowledgements
  8. References

In this large cohort study, we explored the oral hygiene practices and oral health status of Italian postpartum women.

The main findings show that less educated patients were significantly more likely to have severe periodontal disease. Previous studies reported that women with poor education brushed their teeth less frequently than the more educated, thus increasing the risk for dental and gum diseases.[16-18] Interestingly, around 80% had periodontal disease. The subjects attended three Italian tertiary hospitals that also had a dental service. It may be that pregnant women affected by periodontal disease were aware of the presence of dentists in the hospital. As such the high rate of periodontitis reported may not be an indicator of the real rate of prevalence of the disease.

In our study, individuals with three or more dental caries were at higher risk of having periodontitis. Although the majority of patients reported daily toothbrushing (99.1%), a consistent number still had severe periodontal disease. It may be that these patients do not have proper oral hygiene techniques and require more training from an oral health care provider. Indeed, patients who reported a low attendance for dental care (only when in pain) were almost twice as likely to have severe periodontitis.

Emerging data indicate that women with periodontal disease may be at a greater risk of poor obstetric outcomes.[4] As such, given the safety of non-invasive dental procedures during pregnancy,[19] oral therapeutic or preventive services should be provided to every pregnant woman.

Also, patients with three or more dental decays were significantly more likely to have periodontits. It is now recognized that dental caries have a bacterial infection origin that can be transmitted from a parent to an infant.[20, 21] Therefore, health care personnel should identify women at high risk for dental caries, if possible prior to pregnancy, to provide early intervention and motivate their patients about the benefits of good oral hygiene habits.

A relatively high proportion of patients (11%) reported current smoking. Similarly, in 2005 around 10% to 12% of US women reported smoking during pregnancy based on birth certificates.[22] Maternal cigarette smoking during pregnancy increases the risk for poor pregnancy outcomes (e.g. restricted foetal growth, preterm delivery and sudden infant death syndrome) and pregnancy complications (e.g. placenta previa, placental abruption and premature rupture of the membrane).[23] Dentists and prenatal care providers all need to collaborate to promote smoking cessation initiatives for these patients.

One important limitation of this study is the lack of information about socio-economic status (SES) of the participants. Since adult periodontal disease remains prevalent particularly in low SES individuals,[24] we were unable to identify a possible group at higher risk for periodontitis.

Our findings show that pregnant women rarely obtain regular dental care and have dental care needs that are not adequately addressed. This is in agreement with a previous Italian study of our group in which a high proportion of patients (35%) reported seeking oral care only when they experience pain.[25] Given the possible associations between periodontal infection and general health, and between maternal and infant oral health, prenatal care providers should collaborate with dentists and dental hygienists to encourage all pregnant women at the first prenatal visit to schedule a dental visit and comply with the oral health professionals' recommendations regarding appropriate dental brushing techniques and the importance of follow-up visits.

Acknowledgements

  1. Top of page
  2. Abstract
  3. Introduction
  4. Methods
  5. Results
  6. Discussion
  7. Acknowledgements
  8. References

This study was supported by a 2005 grant from the MIUR Italian Ministry of Research – PRIN ‘Research Project of Relevant National Interest’. The authors report no conflict of interest.

References

  1. Top of page
  2. Abstract
  3. Introduction
  4. Methods
  5. Results
  6. Discussion
  7. Acknowledgements
  8. References
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