Influence of implant-supported prosthesis design on peri-implant health: a cross-sectional study.

Background: Peri-implant diseases are common complications that may lead to dental implant failure. An adequate prosthesis design is crucial to reduce the risk of complications, and to improve peri-implant health. The present study was carried out to assess the effect of prosthesis design upon the presence of peri-implant inflammation.

Material and methods: A cross-sectional study was conducted in patients with a single-unit implant-supported screw-retained crown. After removing the crowns, standardized photographs were made to assess several variables such as the length of the submucosal extension (SE) or the emergence angle (EA). Clinical signs of inflammation were also registered, and an experienced clinician probed the implants. The White (WES) and Pink Esthetic Scores (PES) were also recorded. Patients were classified into two groups according to the presence (positive bleeding on probing (BoP+)) or absence (negative bleeding on probing (BoP-)) of inflammation around the dental implant. Independent t-tests and one-way ANOVA were used to analyze the data.

Results: A total of 90 implants were analyzed. Fifty-two implants (57.8%) had BoP+ while 38 (42.2%) had no signs of inflammation of the peri-implant tissues (BoP-). Long SE was significantly associated with BoP+ sites. The EA did not seem to be related to the presence of inflammation (p=0.642). PES/WES showed a negative correlation with buccal EA (r=-0.227; p=0.032).

Conclusions: Long submucosal extensions in single-unit implant-supported crowns seem to be associated with peri-implant tissues inflammation (BoP+). A higher emergence angle on the buccal aspect was associated with poor esthetic outcomes.