Microleakage and sealant penetration in contaminated carious fissures

The aim of the present in vitro study was to evaluate the effect of an adhesive system on microleakage and sealant penetration depth in carious fissures after different surface contamination circumstances.

Extracted third molars (n=128) with small occlusal cavitated carious lesions were randomly divided into eight experimental groups and sealed under four different surface conditions. 1, Dry conditions; 2, water contamination; 3, saliva contamination; 4, saliva contamination and air-drying. Two sealant protocols were applied, one using a fissure sealant (Teethmate F) and one using an additional adhesive system (SA primer and Photo Bond). The control group consisted of sound third molars (n=16), that were sealed under dry conditions. After thermocycling (n=500 cycles), teeth were immersed in 1% methylene blue for 24h, sectioned and digitally photographed. Microleakage was evaluated on a three-point rating scale and analysed using a Chi-square test. Additionally, the presence of caries and incomplete sealant penetration was scored from photographs and analysed using logistic regression.

A statistical significant difference regarding microleakage scores was present between sealed carious and sealed sound fissures. The use of an adhesive system in case of water contamination significantly reduced microleakage (p<0.05). With regard to sealant penetration depth, there were significant differences present for carious sealed fissures, use of an adhesive system prior to sealing, and water and saliva contamination.

Use of an adhesive system improved the effectiveness of sealants placed after water contamination in carious fissures. However, sound fissures showed less microleakage and better penetration abilities than carious fissures.