Interdental spacing and caries in the primary dentition.

PURPOSE This study assessed the relationship between interdental spacing patterns and caries experience in the primary dentition. METHODS Caries examinations were conducted amoung 356 children 4 to 6 years of age. At the time of the examinations, alginate impressions were obtained and poured in yellow stone. From the stone casts, each interdental area was categorized as: (1) space > 1 mm, (2) space < 1 mm, (3) no space, teeth in contact, or (4) no space, teeth overlapped. These categories were collapsed into presence or absence of space for each interdental site, and counted for each individual. Analyses assessed the relationships between interdental spacing and caries experience with separate analyses for anterior spacing, posterior spacing and total spacing. RESULTS Children with more total interdental spaces had less decay experience and less untreated decay than children with fewer interdental spaces, and children with more molar spacing had less molar decay experience; however, these relationships were weak. Correlation analyses demonstrated significant relationships between number of decayed surfaces and total number of interdental spaces (r=-0.11, P=.04) and number of molar sites with interdental spaces (r=-0.13, P=.02). Multivariate analyses revealed the total number of interproximal spaces to be weakly associated with interproximal caries experience, but that fluoride exposure was a much stronger predictor. CONCLUSIONS Absence of interdental spaces is weakly associated with greater decay experience in the primary dentition.