Waithongkam, Amphon, Penpan Laohapand, and Thitiwan Teparat-Burana. 2022. “Patient Accessibility to Supportive Periodontal Therapy and the Occurrence of Recurrent Periodontitis: A Retrospective Study in the Faculty of Dentistry, Mahidol University”. Mahidol Dental Journal 42 (2). Bangkok, Thailand:109-18. https://he02.tci-thaijo.org/index.php/mdentjournal/article/view/254620.