Takuo Kuboki1, Tetsuo Ichikawa2, Kazuyoshi Baba3, Masanori Fujisawa4, Hironobu Sato5, Hideki Aita6, Shigeto Koyama7, Masayuki Hideshima8, Yuji Sato3, Hiroyuki Wake8, Aya Kimura-Ono9, Kan Nagao2, Yorika Kodaira-Ueda10, Katsushi Tamaki11, Shinsuke Sadamori12, Kazuhiro Tsuga12, Yasuhiro Nishi13, Takashi Sawase14, Hisashi Koshino6, Shin-Ichi Masumi15, Kaoru Sakurai10, Kanji Ishibashi16, Takashi Ohyama8, Yasumasa Akagawa12, Toshihiro Hirai6, Keiichi Sasaki7, Kiyoshi Koyano17, Hirofumi Yatani18, Hideo Matsumura19. 1. Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Japan. Electronic address: kuboki@md.okayama-u.ac.jp. 2. Tokushima University Graduate School, Institute of Biomedical Sciences, Japan. 3. Showa University School of Dentistry, Japan. 4. Meikai University School of Dentistry, Japan. 5. Fukuoka Dental College, Japan. 6. Health Sciences University of Hokkaido School of Dentistry, Japan. 7. Tohoku University Graduate School of Dentistry, Japan. 8. Tokyo Medical and Dental University Graduate School of Medical and Dental Sciences, Japan. 9. Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Japan. 10. Tokyo Dental College, Japan. 11. Kanagawa Dental University Graduate School, Japan. 12. Hiroshima University Graduate School of Biomedical Sciences, Japan. 13. Kagoshima University Graduate School of Medical and Dental Sciences, Japan. 14. Nagasaki University Graduate School of Biomedical Sciences, Japan. 15. Kyushu Dental University, Japan. 16. Iwate Medical University Graduate School of Dental Science, Japan. 17. Kyushu University Faculty of Dental Science, Japan. 18. Osaka University Graduate School of Dentistry, Japan. 19. Nihon University School of Dentistry, Japan.
Abstract
PURPOSE: The Japan Prosthodontic Society developed a multi-axis assessment protocol to evaluate the complex variations in patients who need prosthodontic care, and to classify the level of treatment difficulty. A previous report found the protocol to be sufficiently reliable. The purpose of this multi-center cohort study was to evaluate the validity of this multi-axis assessment protocol. METHODS: The treatment difficulty was evaluated using the multi-axis assessment protocol before starting prosthodontic treatment. The time required for active prosthodontic treatment, medical resources such as treatment cost, and changes in the oral health-related QOL before and after treatment, were evaluated after treatment completion. The construct validity of this protocol was assessed by the correlation between the dentist's pre-operative subjective assessment of the treatment difficulty, and the level of difficulty determined by this protocol. The predictive validity was assessed estimating the correlations between a "comprehensive level of treatment difficulty" based on the four axes of this protocol and total treatment cost, total treatment time, and changes in the oral health-related QOL before and after treatment. RESULTS: The construct validity of this protocol was well documented except for psychological assessment. Regarding the predictive validity, the comprehensive level of treatment difficulty assessed before treatment was significantly correlated with the three surrogate endpoints known to be related to the treatment difficulty (total treatment cost, treatment time, and improvement in the oral health-related QOL). To further clarify the validity of the protocol according to patients' oral condition, a subgroup analysis by defects was performed. Analyses revealed that treatment difficulty assessment before treatment was significantly related to one or two surrogate endpoints in the fully edentulous patients and the partially edentulous patients. No significant relationship was observed in the patients with mixture of full/partial edentulism and the patients with teeth problems, possibly due to the small sample size in these groups. CONCLUSION: This study revealed that the multi-axis assessment protocol was sufficiently valid to predict the level of treatment difficulty in prosthodontic care in patients with fully edentulous defects and with partially edentulous defects.
PURPOSE: The Japan Prosthodontic Society developed a multi-axis assessment protocol to evaluate the complex variations in patients who need prosthodontic care, and to classify the level of treatment difficulty. A previous report found the protocol to be sufficiently reliable. The purpose of this multi-center cohort study was to evaluate the validity of this multi-axis assessment protocol. METHODS: The treatment difficulty was evaluated using the multi-axis assessment protocol before starting prosthodontic treatment. The time required for active prosthodontic treatment, medical resources such as treatment cost, and changes in the oral health-related QOL before and after treatment, were evaluated after treatment completion. The construct validity of this protocol was assessed by the correlation between the dentist's pre-operative subjective assessment of the treatment difficulty, and the level of difficulty determined by this protocol. The predictive validity was assessed estimating the correlations between a "comprehensive level of treatment difficulty" based on the four axes of this protocol and total treatment cost, total treatment time, and changes in the oral health-related QOL before and after treatment. RESULTS: The construct validity of this protocol was well documented except for psychological assessment. Regarding the predictive validity, the comprehensive level of treatment difficulty assessed before treatment was significantly correlated with the three surrogate endpoints known to be related to the treatment difficulty (total treatment cost, treatment time, and improvement in the oral health-related QOL). To further clarify the validity of the protocol according to patients' oral condition, a subgroup analysis by defects was performed. Analyses revealed that treatment difficulty assessment before treatment was significantly related to one or two surrogate endpoints in the fully edentulouspatients and the partially edentulouspatients. No significant relationship was observed in the patients with mixture of full/partial edentulism and the patients with teeth problems, possibly due to the small sample size in these groups. CONCLUSION: This study revealed that the multi-axis assessment protocol was sufficiently valid to predict the level of treatment difficulty in prosthodontic care in patients with fully edentulous defects and with partially edentulous defects.