The Clinical Performance of Narrow Diameter Implants Versus Regular Diameter Implants: A Meta-Analysis

The purpose of this study is to analyze 1- and 3-year clinical performances of narrow diameter implants (NDIs) versus regular diameter implants (RDIs). A search of electronic databases and a manual search was performed for the time period January 2000 to April 2018. A meta-regression was used to evaluate the effects of the "fixed effects" model on the implant survival rates, prosthesis success rates and marginal bone loss (MBL) with follow-up time of 1 year and 3 years. Of the 11 studies included, the overall combined 1-year implant survival rates were 98.14% for NDIs and 98.20% for RDIs. The overall combined 3-year implant survival rates were 98.71% for NDIs and 98.84% for RDIs. The corresponding values for 1-year prosthesis success rates were 96.94% for NDIs and 99.25% for RDIs. The corresponding values for 3-year prosthesis success rates were 89.25% for NDIs and 96.55% for RDIs. The meta-regression showed no significant differences between NDIs and RDIs regarding implant survival rates, prosthesis success rates, and MBL in 1-year and 3-year follow-up (P > .05). The results of this meta-analysis concluded that the implant diameter did not affect its survival rates, prosthesis success rates, and MBL in 1 and 3 years. The use of NDIs instead of bone augmentation procedures with RDIs did not affect its survival rates, prosthesis success rates, and MBL in the short-term and middle-term. However, more high-quality randomized controlled trials and long follow-up studies are needed on this topic.