Influence of Dental Implant Diameters on Prosthesis Complications: A Systematic Review and Meta-analysis

To analyze the risk of prosthesis complications for dental implants across different diameters.

An electronic search in PubMed (MEDLINE), Embase, Scopus, and Cochrane Central Register of Controlled Trials until December 2023 was performed. Studies that compared implant prosthesis complications among the following implant types were included: extra-narrow (EDNIs; < 3.0 mm), narrow (NDIs; ≥ 3.0 to < 3.75 mm), standard (SDIs; ≥ 3.75 to < 5 mm), and wide-diameter (WDIs; ≥ 5 mm) implants. Meta-analyses were performed to evaluate the risk ratio of prosthesis complications across different diameters, particularly in non-full-arch implant-supported fixed dental prostheses (ISFDPs).

A total of 18 clinical studies were included. In non-full-arch ISFDPs, the most prevalent complication was screw loosening in NDIs, SDIs, and WDIs (1.73%, 4.08%, and 12.45%, respectively) and decementation (3.4%) in ENDIs. In implant overdentures, ENDIs, NDIs, and SDIs demonstrated high rates of retentive cap wear (58.33%, 80.49%, and 70%, respectively), whereas WDIs had 16.67% overdenture repair. The meta-analyses showed a risk ratio of 0.20 (95% CI = 0.04 to 0.94, P = .04) and 0.17 (95% CI = 0.06 to 0.45, P < .0004) for abutment fracture in single crowns and ISFDPs comparing NDIs and SDIs. No significant differences in risk ratios were observed for screw loosening, decementation, porcelain chipping, fracture, or screw fracture among the different diameter groups.

This systematic review highlights that screw loosening and retentive cap wear are the most common prosthesis complications in ISFDPs and overdentures, regardless of implant diameter. While NDIs have a lower risk of abutment fracture compared to SDIs, clinicians should carefully consider patient characteristics, implant locations, and abutment features when selecting the ideal implant diameter.