Radiographic pattern of inactive occlusal enamel lesions and its relationship with caries progression over 4-5 years

To assess the radiographic pattern of inactive enamel caries lesions (IECL) in the occlusal surfaces of permanent molars and to investigate whether the presence of radiolucency at baseline could predict lesion progression over 4-5 years.

A prospective cohort study followed 193 schoolchildren from southern Brazil. At baseline, clinical and radiographic examinations were performed. After 4-5 years, clinical examination was repeated following the same protocol. Logistic regression models were used to investigate the relationship between the presence of radiolucency at baseline and caries progression.

This study included 916 permanent molars, classified as sound occlusal surfaces (n = 434), non-cavitated IECL (n = 438), or cavitated IECL (n = 44) at baseline. The proportion of lesions with radiolucency increased as lesion severity increased (p<0.001, chi-square test). The proportion of cases that progressed was significantly higher among teeth showing radiolucency at baseline than among teeth without radiolucency (p<0.001, chi-square test). The presence of radiolucency at baseline was found to be a predictor of caries progression (activity criteria, adjusted OR=3.37, 95%CI=1.66-6.82, p<0.001; severity criteria, adjusted OR=4.01, 95%CI=1.85-8.72, p<0.001).

Occlusal surfaces (either sound or with IECL) presenting radiolucency at baseline were more likely to progress over 4-5 years of monitoring and should be monitored more closely.

Bitewing radiographs, when available, may be used to identify which surfaces/lesions are more likely to progress and thus, to define proper recall intervals for patient monitoring.