Prevalence of OXIS Contacts between the Primary Molars in 3 to 9 Years Old Children: A Cross-sectional Study

Abstract

Introduction: Interproximal contacts between primary teeth have traditionally been reported as broad and flat. A new system of classification for contacts called OXIS- O (open contact), X (point contact), I (straight contact), and S (curved contact) was introduced in 2018, based on the shapes observed occlusally. Understanding interproximal contacts in primary teeth is essential to comprehend the caries risk of the individual. Aim: To assess the prevalence of OXIS contact areas between non carious primary molars in 3 to 9 years old children and to determine the most common type of contact before and after the eruption of the first permanent molar. Materials and Methods: A cross-sectional study was conducted to determine the prevalence of the types of contacts between primary teeth through direct observation in a sample size of 260 contact areas. The study was carried out in the Department of Paediatric and Preventive Dentistry, Navi Mumbai, India, between August 2022 to February 2023. Ethical clearance from the university was obtained. A single calibrated examiner examined photographs of the interproximal contacts between primary molars. The contacts were assessed as O (open contact), X (point contact), I (straight contact), and S (curved contact) using the OXIS classification system. The prevalence of each contact type was recorded. Statistical analysis was performed using Statistical Package for Social Sciences (SPSS) 18.0 software. The prevalence of contact types was recorded in numbers and percentages. A comparison of contact types before and after the eruption of the first permanent molar was conducted using the Chi-square test. Result: The most common contact type was I (65.00%) both before and after the eruption of the first permanent molar. This was followed by S (19.62%), X (11.15%), and O (4.23%) in the primary dentition. After the eruption of the first permanent molars, I contact was the highest at 66.41%, followed by S (20.90%), X (12.68%), and O (0%). Conclusion: This study confirms the presence of O, X, I, and S types of interproximal contact areas in caries-free primary molars in 3 to 9 years old children.