Interventions for replacing missing teeth: different times for loading dental implants

 

Abstract

Background

To minimize the risk of implant failure, osseointegrated dental implants are conventionally kept load-free during the healing period. During healing removable prostheses are used, however many patients find these temporary prostheses rather uncomfortable and it would be beneficial if the healing period could be shortened without jeopardizing implant success. Nowadays immediately and early loaded implants are commonly used in mandibles (lower jaws) of good bone quality. It would be useful to know whether there is a difference in success rates between immediately or early loaded implants compared with conventionally loaded implants.

Objectives

To evaluate the efficacy of (1) immediate (within 1 week), early (between 1 week and 2 months), and conventional (after 2 months) loading of osseointegrated implants, and of (2) immediate occlusal versus non-occlusal loading during the bone healing phase.

Search methods

The Cochrane Oral Health Group's Trials Register, CENTRAL, MEDLINE and EMBASE were searched. Handsearching included several dental journals. Authors of all identified trials, an Internet discussion group and 55 dental implant manufacturers were contacted to find unpublished randomised controlled trials (RCTs). The last electronic search was conducted on 4 June 2008.

Selection criteria

All RCTs of root-form osseointegrated dental implants, having a follow up of 4 months to 1 year, comparing the same implant type immediately, early and conventionally loaded or occlusally and non-occlusally loaded. Outcome measures were: prosthesis and implant failures and radiographic marginal bone level changes.

Data collection and analysis

Data were independently extracted, in duplicate, by two review authors. Authors were contacted for details of randomisation and withdrawals and a quality assessment was carried out. The Cochrane Collaboration's statistical guidelines were followed.

Main results

Thirty RCTs were identified and 22 trials including 1024 participants in total were included. Twelve trials compared immediate versus conventional loading, three early versus conventional loading, six immediate versus early loading, and one occlusally versus non-occlusally loaded implants. On a patient, rather than per implant basis, there were no statistically significant differences for any of the meta-analyses.

Authors' conclusions

It is possible to successfully load dental implants immediately or early after their placement in selected patients, though not all clinicians may achieve optimal results. It is unclear whether it is beneficial to avoid occlusal contacts during the osseointegration phase. Trends suggest that immediately loaded implants fail more often than those conventionally loaded, but less commonly than those loaded early. If a clinician wishes to load the implants early, it might be wiser to load them immediately (within 1 week) rather than waiting for 1 or 2 months. A high degree of primary implant stability (high value of insertion torque) seems to be one of the prerequisites for a successful immediate/early loading procedure. More well designed RCTs are needed and should be reported according to the CONSORT guidelines (www.consort-statement.org/).

 

Plain language summary

Interventions for replacing missing teeth: different times for loading dental implants

Some people may be able to have artificial teeth attached to dental implants immediately instead of having to wait for months, but more research is needed to be sure.
When people have dental implants in their jaws, they wait several months for the bone around the implants to heal before artificial teeth are attached (using removable dentures in the meantime). If artificial teeth could be loaded onto the implant immediately, people might be able to start chewing comfortably the same day or within weeks. The review found some evidence from studies that immediate or early loading of artificial teeth may have a slightly poorer outcome than conventional (after waiting for several months) loading. However, it is possible to successfully load dental implants immediately or early after their placement in selected people, although not all clinicians may obtain such good results.

 

摘要

背景

取代缺牙的介入方式:不同的植體受力時機

為了減少植體失敗的風險,骨整合的植體傳統上都會在植體癒合的期間保持不受力的狀態.在癒合的期間,會使用活動式補綴裝置,然而許多病人覺得這些臨時性的補綴裝置不舒適,而且如果癒合期能縮短而不危及植體成功的話是有幫助的.如今植體立即和早期受力常用於下顎良好的骨質區.如果能知道立即或早期受力和傳統受力時機的植體間有無成功率上的差異是有幫助的.

目標

為了評估(1)立即受力(一星期內), 早期受力(介於一星期到二個月之間)和傳統受力模式(二個月後)間的效益以及(2)在骨癒合期立即承受咬合力和無咬合接觸間的效益.

搜尋策略

搜尋Cochrane Oral Health Group's Trials Register, CENTRAL, MEDLINE 和 EMBASE 等網站上的資料.手工搜尋則包括許多牙科期刊.聯絡所有搜尋到的實驗中的作者,網路上的討論族群以及55家牙科植體製造商來找出尚未發表的隨機對照試驗.最後一次電子搜尋於2008年6月4日完成.

選擇標準

所有關於牙根型骨整合牙科植體的隨機對照試驗,4個月到一年間的追蹤,比較同樣植體類型在立即受力,早期受力和傳統受力方式的差異或比較咬合受力和無咬合接觸狀況下的差異.評估方式為:贗復體和植體的失敗以及放射線檢查植體周圍骨頭位置的變化.

資料收集與分析

由二位檢閱者將資料重複並獨立的篩選.和實驗的作者聯繫來得到隨機試驗和移除樣本的詳細資料並進行實驗的品質分析.參考Cochrane Collaboration 的統計準則來作分析.

主要結論

總共找到了30個隨機對照試驗,其中選入22個實驗,包括976個樣本.有12個實驗比較立即受力和傳統受力模式的差異,3個實驗比較早期受力和傳統受力模式,6個實驗比較立即受力和早期受力模式,還有一個實驗比較咬合接觸和無咬合接觸.若以每個病人而非以每隻植體為基準來看,在這些統合分析(metaanalysis)中,並無統計學上的顯著差異.

作者結論

在某些病人植入的植體給予立即或早期施力或許可以成功,但並非所有的臨床醫師都可以達到理想的結果.究竟避免在骨整合階段給予咬合接觸是不是有利的並不清楚.目前的趨勢是立即受力的植體比傳統受力方式的植體較常發生失敗,但比早期受力的植體不易失敗.如果臨床醫師想要早期施力於植體上,立即受力(一星期內)的方式比等待1到2個月後再施力的方式可能是較明智的選擇.較高程度的植體初期穩定性(旋入扭力數值大)似乎是能成功達成立即/早期受力方法的必要條件.更多設計完善的隨機對照試驗是需要的而且應該遵循CONSORT規定的準則來發表(www.consortstatement.org/).

翻譯人

本摘要由臺灣大學附設醫院鄭偉立翻譯。

此翻譯計畫由臺灣國家衛生研究院(National Health Research Institutes, Taiwan)統籌。

總結

有些人或許可以在植體植入後立即將義齒接上而不需要等待幾個月,但需要更多的研究來確定這種處理方式.當病人有植體在顎骨內,通常需要等待好幾個月讓植體周圍的骨頭癒合才能接上義齒(在這期間配戴活動義齒).如果義齒能在植體植入後立即裝上,病人就可以在植完牙的當天或幾星期內開始舒適地咀嚼.這篇文獻回顧發現從研究中得到一些證據顯示立即或早期施力於義齒相較於傳統受力模式(等待幾個月後才施力)會有些許不好的結果產生.然而在某些病人植入植體後給予立即或早期施力或許可以成功,但並非所有的臨床醫師都可以達到這樣理想的結果.