YIJOM-3031; No of Pages 12
Int. J. Oral Maxillofac. Surg. 2014; xxx: xxx–xxx http://dx.doi.org/10.1016/j.ijom.2014.10.023, available online at http://www.sciencedirect.com
Systematic Review Paper Dental Implants
Evaluation of survival and success rates of dental implants reported in longitudinal studies with a follow-up period of at least 10 years: a systematic review
V. Moraschini1, L. A. da C.Poubel2, V. F. Ferreira3, E. dos S. P.Barboza1 1
Department of Periodontology, Fluminense Federal University, Nitero´i, Brazil; 2 Department of Clinical Dentistry, Fluminense Federal University, Nova Friburgo, Brazil; 3 Department of Periodontology, State University of Rio de Janeiro, Rio de Janeiro, Brazil
V. Moraschini, L. A. da C. Poubel, V. F. Ferreira, E. dos S. P. Barboza: Evaluation of survival and success rates of dental implants reported in longitudinal studies with a follow-up period of at least 10 years: a systematic review. Int. J. Oral Maxillofac. Surg. 2014; xxx: xxx–xxx. # 2014 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.
Received ; received in revised form ; accepted
Abstract. The aim of this systematic review was to evaluate the survival and success rates of osseointegrated implants determined in longitudinal studies that conducted a follow-up of at least 10 years. A broad electronic search was conducted in MEDLINE/PubMed and the Cochrane Central Register of Controlled Trials (CENTRAL) for relevant publications in indexed journals, evaluating the clinical performance of dental implants. Using inclusion and exclusion criteria, two reviewers analyzed titles, abstracts, and complete articles, prioritizing studies of the randomized clinical trial type. A total of 23 articles were included in this review. Ten prospective studies, nine retrospective studies, and four randomized clinical trials, which evaluated 7711 implants, were selected. The mean follow-up time of the studies included was 13.4 years. All of the studies reported survival rates and mean marginal bone resorption values, with cumulative mean values of 94.6% and 1.3 mm, respectively. Fourteen studies related success rates. Taking into consideration the disparate outcome measures employed to assess dental implant performance and within the limitations of this systematic review, we may affirm that osseointegrated implants are safe and present high survival rates and minimal marginal bone resorption in the long term.
Key words: dental implant; survival of implants; success of implants; systematic review. Accepted for publication 30 October 2014
# 2014 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.
Please cite this article in press as: Moraschini V, et al. Evaluation of survival and success rates of dental implants reported in longitudinal studies with a follow-up period of at least 10 years: a systematic review, Int J Oral Maxillofac Surg (2014), http://
YIJOM-3031; No of Pages 12
Moraschini et al.
The first longitudinal studies evaluating osseointegrated implants showed satisfactory results.1,2 Today, with over 40 years of scientific evidence, the clinical use of implants has increased by the day. Nevertheless, few studies have conducted followup for periods longer than 10 years, which is fundamental to enable us to understand the biological behaviour of implants.3 In longitudinal studies on osseointegrated implants, the terms ‘survival’ and ‘success’ are used routinely. However, these terms continue to generate confusion with regard to their real meanings,4 and are frequently used incorrectly, even in scientific studies. Knowledge and standardization of these terms is necessary to facilitate communication, comparison, and complete understanding among professionals in this field.5–8 Studies on success rates in implant dentistry are complex because of the large number of existing variables, such as surgical techniques, materials used, and duration of follow-up. In addition, various criteria have been proposed for the definition of success,6,7,9–14 and the absence of international standardization makes comparison between studies difficult.6,15 The aim of this study was to evaluate, by means of a systematic review of the literature, the survival and success rates of osseointegrated implants determined in longitudinal studies with follow-up periods of at least 10 years. Materials and methods Focused question and study objective
The focused research question was ‘‘What is the survival and success rate of implants in a period of at least 10 years of follow-up?’’ The objective of this systematic review was to attempt to fill the void in the literature related to the long-term survival and success data of dental implants. This knowledge provides a basis on which the clinician can make decisions in treatment planning.
Development of a protocol
To investigate the survival/success rate of implants, an extensive search was done to identify longitudinal studies in humans, in which follow-up of at least 10 years was conducted. This systematic review was carried out in accordance with the steps of practice based on scientific evidence16 and the methodology was adapted to the PRISMA statement (Preferred Reporting Items for Systematic Reviews and MetaAnalyses).17 The clinical questions of this review were broken down and organized
using the PICO strategy (population, intervention, comparison, outcome), as proposed by evidence-based practice.16,18
number of implants, implant systems, size of implants, type of dental prosthesis, mean probing depth, mean marginal bone loss, success rate, criteria of success, survival rate, and author conclusions.
A broad electronic search was made from January 2012 to November 2013 in the database of the National Library of Medicine, Washington, DC (MEDLINE/ PubMed) and the Cochrane Central Register of Controlled Trials (CENTRAL) for relevant publications in indexed journals. The search strategy was implemented using the following key words: ((endos$) OR (dental) OR (osseointegra$)) and ((implant$) OR (fixture$)) and ((prospective) OR (retrospective) OR (comparative) OR (longitudinal)). The following criteria had to be met for inclusion: (1) human study (partially or completely edentulous); (2) publication in English; (3) randomized controlled clinical trial (RCT), or cohort prospective or retrospective study; (4) minimum period of follow-up of 10 years; (5) study evaluating the survival or success rate and level of marginal bone resorption around osseointegrated implants. The following were excluded: animal studies, case reports and narrative reviews, and studies involving zygomatic implants, patients undergoing radiotherapy, chemotherapy or those making use of bisphosphonates, implants placed in areas of bone regeneration, bone resorption analyzed by means of panoramic radiographs, patients with systemic diseases including autoimmune diseases, syndromes, and osteoporosis, patients under the age of 18 years, and those with periodontitis without previous treatment. Studies classified as having a high risk of bias according to the specific analysis carried out were also excluded. The papers were first screened independently by two reviewers (V.M.F. and E.P.B), by title and abstract. Next, as a second step, the full-text papers were read in detail. Those papers that fulfilled all selection criteria were processed for data extraction. Disagreements were resolved by discussion. If disagreement persisted, the judgement of a third reviewer (V.F.F.) was decisive.
Assessment of heterogeneity
To evaluate the heterogeneity of the primary outcome between the selected studies, the following factors were recorded: study design, follow-up time, primary objective of the study, number of participants, gender, number of drop-outs, age range, mean age,
With a view to increasing the reliability of the studies included, and to diminish the risk of bias, a careful quality analysis was done. The methodology used for analysis of the studies was that proposed by Nguyen et al.19 combined with the PRISMA criteria,17 Needleman guide,20 and the Cochrane recommendations to evaluate the risk of bias.21 The methodology of the RCT studies was evaluated in accordance with the RCT checklist available in the CONSORT statements.22,23 Table 1 lists the various criteria assessed with their potential scores, which added together generate a maximum possible score of 16 points. Table 2 shows the evaluation of the articles identified for inclusion;3,6,24–48 the methodological quality of each study was classified according to the potential risk of bias: low (score >12), moderate (score 10–12), or high (score