PERIODONTAL INDEX CREATION METHOD, PERIODONTAL INDEX CREATION APPARATUS, PERIODONTAL INDEX CREATION PROGRAM, AND RECORDING MEDIUM HAVING RECORDS OF PERIODONTAL INDEX CREATION PROGRAM, AND PERIODONTITIS DIAGNOSIS METHOD, PERIODONTITIS DIAGNOSIS APPARATUS, PERIODONTITIS DIAGNOSIS PROGRAM, AND RECORDING MEDIUM HAVING RECORDS OF PERIODONTITIS PROGRAM

摘要

As subjects, teeth having been considered as non-preservable and thus extracted are used and several teeth of each tooth type are selected and subjected to measurement. Then, the lost periodontal ligament area (SL) of each tooth is calculated on the basis of the sample attachment level (M) and total periodontal ligament area (S) thereof. Next, the relationship between the bite force coefficient (B), which reflects the bite force of each tooth and varies from tooth type to tooth type, and the lost periodontal ligament area (SLB) at loosing of each tooth is statistically processed for each tooth group. By taking advantage of the linear relationship between these factors existing in this step, a linear equation representing the relationship between the bite force coefficient (B) and the lost periodontal ligament area (SLB) at tooth loosing is formed. Thus, [remaining periodontal ligament area modified by bite force (SSB)]/total periodontal ligament area (S)]x100 ( pcnt ) is calculated, on the basis of the lost periodontal ligament area (SLB) at tooth loosing, as a periodontal index modified by bite force (BPI) that shows the degree of the progress of periodontitis.