ABSTRACT
This study examined the relationship between the status of the interproximal alveolar bone and the nature of the adjacent proximal surfaces in the primary molar area. In bite wing radiographs of 354 children, aged 6 to 9 years, 5091 sites were examined; 72.7% of the sites were adjacent to intact proximal surfaces, 14.2% to untreated proximal carious surfaces, and 13.0% to restored proximal surfaces. Marginal alveolar bone loss (ABL) was evident in 26.8% of the children, at 4.0% of the sites. Two thirds of the children with ABL had bone defects in more than 1 site. Males had a significantly higher mean number of sites affected with marginal ABL, per child, than females (mean = 2.4, SE = 0.2 and mean = 1.8, SE = 0.2 respectively). ABL was found adjacent to: 0.8% of the intact surfaces; 16.9% of the carious surfaces; 7.8% of the restored surfaces; 1.8% and 53.8% of the sites without or with proximal contact loss respectively; 3.8% and 30.8% of the sites with or without an adequate amalgam restoration respectively; 4.9% and 25.8% of the sites with an adequate or inadequate crown restoration respectively. The differences in distribution of marginal alveolar bone loss were highly significant (Chi square analysis, p = < 0.0001) for sites with intact, carious or restored sites, and for the presence or absence of contact loss, adequate amalgam or adequate crown.