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Evaluation of the Marginal Fit of Implant-Supported Crowns.

Marginal adaptation is an important feature of implant-supported crowns, ensuring long-term survival and the success of the prosthetic restoration. The long-term success of a fixed prosthesis such as an implant is highly associated with its marginal adaptation. Improper marginal adaptation increases the risk of plaque accumulation, which leads to decay and periodontal diseases and eventually results in the failure of the fixed dental restoration. The aim of this study is to evaluate the marginal fit of different types of implant-supported crowns following the cementation procedure. It is a retrospective study conducted by reviewing 86,000 patient case records of the Saveetha Dental College and Hospital, Chennai, India. A total of 196 consecutive case records of patients for a period of June 2019 to March 2020, with signed informed consent, were retrieved and analyzed. Information such as patient name, patient identification number (PID), age, gender, marginal adaptation, and type of materials was retrieved from patient case records. Data were entered in Excel and analyzed using SPSS software version 23.0. Descriptive analysis was done for the assessment of age, gender, type of materials, and marginal adaptation. A Chi-square test was used to evaluate the association between marginal adaptation and type of materials. The significant level was set at less than or equal to 0.05 (p ≤ 0.05). In this study, we observed that all-metal, metal-ceramic, hand-layered, and monolithic crowns mainly have smooth margins adaptation (52.55%) following cementation. The placement of implant-supported crowns is mostly done in individuals within the 21-30 years age group (29.08%). A higher prevalence of implant-supported crowns is seen in males (61.73%) compared to females (38.27%). Within the limits of the study, placement of implant-supported crowns is done mainly in individuals within the 21-30 years age group, with higher predilection in males compared to females. Metal-ceramic crowns are commonly placed, followed by hand-layered crowns, monolithic crowns, and all-metal crowns. Most of the implant-supported crowns exhibit satisfactory marginal adaptation with smooth margins. However, there is no significant association between the types of material and marginal adaptation.