The Associated Factors of Proximal Contact Loss between Implant-supported Fixed Prosthesis and Adjacent Tooth

YU Tingting; FANG Tiejun; JIANG Ying; CHEN Junlan; XU Junxi

doi:10.3969/j.issn.1672-7185.2025.03.009

Abstract：Objective The aim of this study was to evaluate the incidence of proximal contact loss(PCL)between implant-retained fixed prostheses and adjacent natural teeth and to analyze the affecting factors.Methods Forty patients who underwent implant restorative treatment in the posterior region at Zhongshan Dental Hospital from December 2022 to December 2023 were selected for the study,and the adjacency strength was measured using a 20 μm metal sheet and a digital dynamometer,and was tested at the time of implant crown and bridge dentistry,1 month,3 months and 6 months of dentistry,respectively.Results Among the 80 implant-retained fixed denture adjacent contact points,the incidence of proximal-medial PCL was 10.00%(4/40),distal-medial PCL was 7.50%(3/40),and the total incidence was 8.75%(7/80)at 1 month after tooth wearing;the incidence of proximal-medial PCL increased to 35.00%(14/40),distal-medial was 7.50%(3/40),and the total incidence was 21.25%(17/80)at 3 months after implantation;at 6 months the incidence of proximal-medial PCL was 22.50%(9/40),distal-medial was 15.00%(6/40),and the total incidence was 18.75%(15/80).There was a significant correlation between the position of the jawbone where the implants were located and the incidence of PCL in the early post-dental period.Conclusion The adjacency between implant-retained fixed denture and natural neighboring teeth is constantly changing over time,and the maxillary position may be a risk factor for the occurrence of PCL in the early period.Clinicians should consider this factor when developing treatment plans and provide appropriate patient education and regular follow-up.