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Dental implants

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

Evidence-Based Dentistry volume 24, pages 100–101 (2023)Cite this article

Subjects

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.

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Author information

Authors and Affiliations

  1. Lecturer of Prosthodontics, Faculty of Dentistry, Cairo University, Cairo, Egypt

    Huda Fouad

  2. Lecturer of Prosthodontics, Faculty of Dentistry, Galala University, Galala, Egypt

    Mohamed Aboheikal

Authors
  1. Huda Fouad
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  2. Mohamed Aboheikal
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Corresponding author

Correspondence to Huda Fouad.

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The authors declare no competing interests.

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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

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