Evidence about biological and technical complications regarding tilted versus straight implants supporting fixed dental prostheses

ABSTRACT TYPE OF STUDY DESIGN Systematic review and meta-analysis. DATA SOURCES MEDLINE, Embase, and Web of Science for English studies published until December 2017 using a controlled

vocabulary (MeSH, Emtree) with no time restrictions were searched. The system for information on Grey literature in Europe (SIGLE), a manual search of all issues since 2000 of several

implant-related journals, and reference list of all included studies were additionally surveyed by two reviewers in duplicate. STUDY SELECTION Two reviewers assessed papers for eligibility

by title and abstract and then by full text in duplicate. Disagreements were solved by a discussion with a third reviewer where agreement was almost perfect (κ = 0.91). Randomized (RCTs) and

non-randomized clinical studies with a minimum follow-up of 3 years and minimum sample size of 20 patients reporting on biological, prosthetic complications, and patient-related outcome

measures (PROMs) were eligible. The primary outcome was the biological complication of implant failure and the main secondary outcome was peri-implant marginal bone loss (MBL). DATA

EXTRACTION AND SYNTHESIS No RCTs were found and eligible Non RCTs were assessed for risk of bias using ROBINS-I Tool. Implant failure and peri-implant MBL measured radiographically in mm

were assessed between the two groups using relative risk and mean difference respectively with 95% confidence interval. Meta-analysis was conducted using a random effects model with

Paule-Mandle estimator as wide variation of true effects was expected. Additional subgroup and sensitivity analyses were performed as well as rating the quality of meta-evidence using GRADE

approach. MAIN RESULTS 17 non-randomized studies (8 prospective and 9 retrospective) including a total of 7568 implants were included. Meta-analysis showed no difference in implant failure

in 8 studies (RR = 0.95; 95% CI = 0.7 to 1.28; _p_ = 0.74). Also, no significant difference was found in MBL in 16 studies (MD = 0.03 mm; 95% CI = −0.03 to 0.10 mm; _p_ = 0.32). CONCLUSIONS

Considering the serious risk of bias of included studies, heterogeneity, and lack of randomized controlled clinical studies, the placement of tilted implants showed no added risk of failure

or increased MBL compared to straight implants. Access through your institution Buy or subscribe This is a preview of subscription content, access via your institution ACCESS OPTIONS Access

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subscriptions * Read our FAQs * Contact customer support REFERENCES * Pjetursson BE, Tan K, Lang NP, Brägger U, Egger M, Zwahlen M. A systematic review of the survival and complication rates

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meta-analysis. J Dent. 2015;43:149–70. https://doi.org/10.1016/j.jdent.2014.09.002. Article  PubMed  Google Scholar  Download references AUTHOR INFORMATION AUTHORS AND AFFILIATIONS *

Lecturer of Prosthodontics, Faculty of Dentistry, Cairo University, Cairo, Egypt Huda Fouad * Lecturer of Prosthodontics, Faculty of Dentistry, Galala University, Galala, Egypt Mohamed

Aboheikal Authors * Huda Fouad View author publications You can also search for this author inPubMed Google Scholar * Mohamed Aboheikal View author publications You can also search for this

author inPubMed Google Scholar CORRESPONDING AUTHOR Correspondence to Huda Fouad. ETHICS DECLARATIONS COMPETING INTERESTS The authors declare no competing interests. ADDITIONAL INFORMATION

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THIS ARTICLE CITE THIS ARTICLE Fouad, H., Aboheikal, M. Evidence about biological and technical complications regarding tilted versus straight implants supporting fixed dental prostheses.

_Evid Based Dent_ 24, 100–101 (2023). https://doi.org/10.1038/s41432-023-00896-2 Download citation * Received: 02 April 2023 * Accepted: 11 April 2023 * Published: 11 May 2023 * Issue Date:

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