Diagnosis of caries on approximal surfaces of permanent teeth

Background: Accurate diagnosis of carious lesions, although especially difficult on approximal surfaces of back teeth, is the most important part of minimal intervention therapy. Detection of caries in its initial stage is very important in order to prevent cavitation. The present study focused on the effectiveness of methods routinely used to diagnose approximal caries, prevalence of approximal caries and its specific features, clinical symptomatology, and role of hygienic habits.

Methods: We performed history-taking and physical examination consisting of clinical examination (CE), intra-oral camera viewing (IC), transillumination (TI), and digital bite-wing radiography in a group of 100 patients. Oral hygiene was evaluated with API (Approximal Plaque Index).

Results: The prevalence of caries in the study group was 98%. More than one-third of 3190 approximal surfaces of premolar and molar teeth examined by us demonstrated symptoms of caries in the form of lesions (21.3%), cavities (0.2%), and fillings (11.8%). Approximal surfaces of first lower molars were the most severely affected by caries. Bite-wing radiography disclosed that lesions were limited to enamel (E) on 74.3% of approximal surfaces and reached dentin (D) on 11.5% of surfaces. Other methods of examination provided the following results: CE 29% (E) and 7.8% (D); IC 34.2% (E) and 10.7% (D); TI 35.8% (E) and 7.6% (D). Hygiene was unsatisfactory or mediocre (API > 40) in the majority of patients. Concerning approximal surfaces, there was a significant correlation between hygiene and approximal caries.

Conclusions: High prevalence of approximal caries observed in the study group correlated with poor hygiene. Digital radiography is the most effective method for early detection of approximal carious lesions.