Importance of bitewing radiographs for the early detection of interproximal carious lesions and the impact on healthcare expenditure in Japan

Peter Grieco; Ashiana Jivraj; John Da Silva; Yukinori Kuwajima; Yoshiki Ishida; Kaho Ogawa; Hiroe Ohyama; Shigemi Ishikawa-Nagai

doi:10.21037/atm-21-2197

Importance of bitewing radiographs for the early detection of interproximal carious lesions and the impact on healthcare expenditure in Japan

Ann Transl Med. 2022 Jan;10(1):2. doi: 10.21037/atm-21-2197.

Authors

Peter Grieco¹, Ashiana Jivraj², John Da Silva¹, Yukinori Kuwajima³, Yoshiki Ishida⁴, Kaho Ogawa³, Hiroe Ohyama¹, Shigemi Ishikawa-Nagai⁵

Affiliations

¹ Department of Restorative Dentistry and Biomaterial Sciences, Harvard School of Dental Medicine, Boston, MA, USA.
² Harvard School of Dental Medicine, Boston, MA, USA.
³ Department of Developmental Oral Health Science, Iwate Medical University, School of Dental Medicine, Iwate, Japan.
⁴ Department of Dental Materials Science, School of Life Dentistry at Tokyo, The Nippon Dental University, Tokyo, Japan.
⁵ Department of Oral Medicine, Infection and Immunity, Harvard School of Dental Medicine, Boston, MA, USA.

Abstract

Background: Globally, the direct cost of dental caries is approximately $298B yearly, consuming 5-10% of national healthcare budgets. Bitewing radiographs (BWR) are the standard method of diagnosing interproximal dental caries. In Japan, bitewing radiographs are rarely used. This retrospective observational study was conducted to measure the potential economic impact of carious lesions left undiagnosed and untreated due to this omission of bitewing radiographs.

Methods: The total number of existing carious lesions, the number of undiagnosed lesions, and costs of treating these lesions were calculated from the national database of Ministry of Health, Labor and Wellness in Japan between June 2013 and 2017. The number of affected teeth was estimated using prevalence data and undiagnosed lesions were estimated. The expense associated with treating progressed lesions was calculated using the standard Japanese fee structure. BWR trends were assessed, and analyses were performed to understand the differences between states and populations over time.

Results: The average number of BWR taken monthly per office was 48.3±1.1 (average ± SD). It was calculated that an average of 6,429,155 lesions went undiagnosed per month, 93.5 teeth per practice, and 1.6 teeth per patient. The cost of treating lesions that went undiagnosed and then progressed into more invasive restorations was estimated to be between $57M-$218M more (difference between NaF varnish and class II restorations), and $150M-$443M more (difference between Class II restoration and crown or crown with RCT).

Conclusions: BWRs are crucial in diagnosing a significant number of carious lesions. There is considerable impact on health and cost to the national health system due to undiagnosed lesions. Practitioners need to be educated on reading and understanding BWR, and policy should be changed to cover BWR.

Keywords: Bitewings; cariology; health expenditures; prevention.