Is There an Effect of Crown-to-implant Ratio on Implant Treatment Outcomes? A Systematic Review

Overview

Journal Clin Oral Implants Res

Specialty Dentistry

Date 2018 Oct 12

PMID 30306696

Citations 19

Authors

Henny J A Meijer

Carina Boven

Konstantina Delli

Gerry M Raghoebar

Affiliations

Soon will be listed here.

Abstract

Objectives: High crown-to-implant ratios may lead to complications due to unfavorable occlusal forces, including nonaxial forces, on the bone surrounding the neck of the implant and within the connection of the crown and implant itself. The aim of this study was to perform a systematic review on the influence of crown-to-implant ratio of single-tooth, nonsplinted, implants on biological and technical complications.

Materials And Methods: MEDLINE (1950-January 2018), EMBASE (1966-January 2018), and Cochrane Central Register of Controlled Trials database (1800-January 2018) were searched to identify eligible studies. Inclusion criteria were as follows: crown-to-implant ratio of single-tooth, nonsplinted, implant-supported restorations in the posterior maxilla or mandible and follow-up of at least 1 year. Main outcome measures were as follows: implant survival rate, marginal bone level changes, biological complications, and technical complications. Two reviewers independently assessed the articles. A meta-analysis was carried out for implant survival rate and peri-implant bone changes.

Results: Of 154 primarily selected articles, eight studies fulfilled the inclusion criteria. Study groups presented a mean crown-to-implant ratio varying from 0.86 (with 10-mm implants) to 2.14 (with 6-mm implants). The meta-analysis showed an implant survival of more than 99% per year and mean peri-implant bone changes of <0.1 mm per year. Limited biological and technical complications were reported.

Conclusion: Data reviewed in the current manuscript on crown-to-implant ratio, ranging from 0.86 to 2.14, of single-tooth, nonsplinted, implants did not demonstrate a high occurrence of biological or technical complications.

Citing Articles

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A Retrospective Analysis of the Influence of Crown-to-Implant Ratio on Marginal Bone Loss.

Alhussainan N, AlMugeiren O J Pharm Bioallied Sci. 2025; 16(Suppl 4):S3880-S3882.

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Survival rate of dental implants installed by postgraduate students attending an implantology program in Brazil: A 52-month retrospective analysis.

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Evaluation of the Peri-Implant Tissues of Patients with Severe Bone Atrophy Treated with a New Short and Extra-Short Implant System-A Pilot Study.

de Moraes K, Thome G, Fontao F, Cartelli C, Marcantonio R, Malzoni C J Funct Biomater. 2024; 15(10).

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A retrospective study on the influence of inclination of cusp on implant marginal bone height in patients with periodontal disease.

Pei R, Xiao C, Chen J, Liu H, Chen J, Ge H Acta Odontol Scand. 2024; 83:493-499.

PMID: 39267359 PMC: 11423694. DOI: 10.2340/aos.v83.41226.

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