Purpose: The purpose of this study was to investigate the prosthetic complications of patients with a maxillary complete removable dental prosthesis opposing a mandibular metal-resin implant fixed complete dental prosthesis.
Materials and methods: This study is a retrospective analysis of an ongoing prospective study. Dental records from 46 patients treated with a maxillary complete removable dental prosthesis and a mandibular metal-resin implant-fixed complete dental prosthesis were reviewed for 15 different prosthetic complications. The average recall time was 7.9 years. The percentage of patients exhibiting each complication and corresponding 95% confidence intervals was calculated. Logistic regression analysis determined the effect of recall period, age, and gender on each of the following major complications: tooth fracture, complete denture relines, screw complications, and tooth replacement. The recall period was divided into 3 parts: < or = 2 years, 2 to 5 years, and more than 5 years.
Results and conclusion: Statistical significance was exhibited for complete denture relines, posterior tooth replacement, and screw complications. No abutment or framework fractures were recorded for any of the time intervals. The most common complications were prosthetic tooth fracture, tooth wear, maxillary hard relines, and screw complications. Patients were 1.06 times more likely to require a heat-processed hard reline with each year increase of age. After 2 to 5 years and > 5 years, patients were 3.7 times and 8.5 times more likely to require a hard reline than at < or = 2 years. Patients were 52.5 times more likely to need posterior tooth replacement at > 5 years than at < or = 2 years, and 7.7 times more likely to encounter a screw complication at > 5 years than at < or = 2 years.