2019 Volume 32 Issue 1 Pages 43-47
Objectives : In this study, we investigated the influence of differences of prosthetic mode of maxillary molars on the thickness of mandibular cortical bone.
Subjects and Methods : The subjects were women aged 45 years or older who agreed to this research by January 2017 in two branches of our research institute, with healthy lower jaw dentition, and a fixed-type prosthesis or implant-supporting prosthetic device. The mandibular cortical width (MCW) with respect to the difference in prosthetic mode on each side of the maxilla was measured using a computer aided diagnostic system (CAD) on a panoramic X-ray photograph.
Results : The subjects were 90 women aged 45 to 90 with an average age of 67.4 years. The target prostheses were 135 fixed-type prostheses and 22 restorative prostheses for each side on maxillary molars The 135 cases of fixed-type prostheses included 56 fixed prostheses and 79 implant support prostheses in the mandibular molars. On the other hand, the 22 restorative prostheses were 18 fixed prostheses and 4 implant-supported prostheses in the mandibular molars.
The average MCW was 3.84 mm for the fixed-type prostheses and 3.63 mm for the implant-supported prostheses, both decreasing with age. The MCW for the prosthetic mode of the maxillary molars was as follows. The average MCW of the 135 fixed-type prostheses was 3.70 mm, which showed a decrease with age. The average MCW of the 22 restorative prostheses was 3.14 mm, which showed a decrease with age like the fixed prostheses.
Conclusion : The loss of teeth in the maxilla and mandible affected MCW, and the MCW decreased with age. It is suggested that the occlusal force had an influence on MCW.
