Title: 3198 - Chronological Changes in Supporting Alveolar Bone by RPD Placement


Chie Watanabe (Presenter)
Tokyo Medical and Dental University

Junichiro Wada, Tokyo Medical and Dental University
Koji Mizutani, Tokyo Medical and Dental University
Hiroshi Watanabe, Tokyo Medical and Dental University
Noriyuki Wakabayashi, Tokyo Medical and Dental University


Objectives: For partially edentulous patients with severe periodontal disease, prosthodontic reconstruction of dentition and occlusal rehabilitation, along with supportive periodontal therapy (SPT), is essential for prevention of further tooth loss. However information on the effects of denture placement on patients with moderate-to-severe periodontal diseases is lacking. The purpose was to assess the early effects of RPD placement on abutment teeth in patients with periodontal disease.

Methods: Fifteen distal-extension RPDs and 19 abutment teeth were evaluated in 13 patients with moderate-to-severe periodontal diseases. Clinical periodontal records and grey level (GL) score based on digital subtraction radiography were measured on the day of denture placement (baseline) and at 1 day, 1 week, 1 month, 3 months, 6 months, and 1 year after the placement. Occlusal force on total dentition (Ft) and abutment teeth (Fa) were recorded with (baseline) and without denture on the day of the placement, and with denture in the follow-up examinations. The stress distributions within the alveolar bone were analyzed using three-dimensional mathematical models.

Results: No statistically significant difference between a follow-up period and the baseline was found in the clinical periodontal and occlusal force records, except for Ft with denture on the day of the placement, which was significantly lower than the baseline (p<0.05). The GL at distal crestal of the abutment was significantly higher at 1 week after the placement than at the baseline (p<0.05), while the scores of following examinations returned to the baseline level.

Conclusions: The digital subtraction radiographic analysis confirmed the evidence of transitory reaction to mechanical stress in the distal crestal bone of the abutment tooth in the early days after the denture placement, while that increased level returned to the baseline level after that. The periodontal conditions based on clinical periodontal parameters remained unchanged during 1 year in this study.

Student Presenter

This abstract is based on research that was funded entirely or partially by an outside source:
The Ministry of Education, Culture, Sports, Science, and Technology of Japan (No. 15K20430)

Disclosure Statement:
The submitter must disclose the names of the organizations with which any author have a relationship, the nature of the relationship, and the clinical or research area involved. The following is submitted: NONE