Survival rate and clinico-radiographic parameters around narrow-diameter dental implants for fixed dental prostheses in the posterior regions: A systematic review.

Abstract

Narrow-diameter dental implants (NDDIs) are suggested to be a reliable alternative to bone augmentation techniques, but the evidence regarding the feasibility of NDDIs in the posterior area is limited. This review investigated the survival rates of NDDIs, as well as peri-implant clinical and radiographic parameters for fixed dental prostheses in the posterior regions in comparison with standard-diameter dental implants (SDDIs). One investigator performed an electronic search of the English literature until December 2020 in the Web of Science, PubMed, Scopus, and EMBASE databases. The focused question was: "Do narrowdiameter dental implants restoring a fixed dental prosthesis demonstrate more alveolar bone loss as compared to standard-diameter dental implants in posterior maxillary and mandibular regions?" The 9 studies selected for this review assessed a total of 498 patients (250 males and 206 females; 42 patients not described in terms of gender) aged 19-81 years, with 725 NDDIs and 260 SDDIs placed. The mean follow-up duration was 71 months (range: 12-176 months). A high survival rate of NDDIs was noticed (97.4%; range: 94.7-100%). The mean probing depth (PD) and bleeding on probing (BOP) scores ranged between 3.12 mm and 3.67 mm, and between 10.00% and 33.42%, respectively. However, the only study reporting the plaque index (PI) demonstrated a mean PI score of 1.39. The majority of the studies reported the mean marginal bone loss (MBL) scores below 1 mm. In conclusion, NDDIs appear to be a feasible treatment option in patients requiring a fixed dental prosthesis in the posterior region, since they exhibit comparable survival rates to SDDIs, as well as a clinically acceptable peri-implant clinical and radiographic tissue response.