Cross-Cultural Adaptation of The Indonesian Version Functional Assessment of Denture Instrument as a Measuring Tool for Complete Denture Functional Quality.

Objective:  Making good quality dentures is necessary to avoid patients' discomfort when adapting to new dentures. Several studies regarding the assessment of the quality of dentures have been carried out in many other countries, such as using the Functional Assessment of Dentures (FAD) by Anastassiadou. However, studies have yet to be conducted in Indonesia. This study aims to obtain a valid and reliable instrument to measure the quality of complete dentures (CDs). This study also aims to find out whether the functional quality of a CD measured with the Indonesian version of the FAD Instrument (PFGT) can affect patient satisfaction in receiving CD treatment (measured with Indonesian version of Patient's Denture Assessment [PDA-Id]) and to find contributing factors to the functional quality of a CD.

Materials and methods:  The study was conducted in two stages. The first stage was a qualitative study using cross-cultural adaptation methods and focus group discussions with experts. The second stage was a quantitative test with a total of 40 subjects for statistical analysis in the form of a kappa test, test-retest, Kuder-Richardson (KR) 20, and a correlation test between PDA-Id and PFG. Multivariate analysis was done to analyze contributing factors to the functional quality of CD.

Results:  The final instrument was obtained from the qualitative test, which was tested for content and face validation. The interrater kappa test result of 0.828 shows an almost perfect agreement. The results of the intrarater test-retest (0.564; p > 0.05; intraclass correlation coefficient 0.889) showed excellent instrument stability. The results of the internal consistency test with Kuder-Richardson 20 (1.08; KR > 1) showed good internal consistency. The correlation test results between PFGT and PDA-Id (0.044; p < 0.05) showed a positive correlation. Multivariate analysis showed a relationship between the quality of the CD, the length of time the CD was used, and the patient's satisfaction with CD treatment.

Conclusion:  The PFGT instrument is considered a valid and reliable tool to measure the functional quality of a denture that can distinguish between good and bad quality.