Chemical, morphological and microhardness dentinal changes after chemomechanical caries removal

Abstract

OBJECTIVES: This study compared the chemical, morphological and microhardness changes in carious dentin following application of NaOCl-based (Carisolv), papain-based (Papacarie) chemomechanical caries removal agents with rotary method. Material and METHODS: Twenty carious and 5 non-carious human permanent molars were used in the study. The 20 carious molars were randomly distributed into four groups (n=5), depending on the caries removal method. Group 1 (positive control): molars were left without caries removal, Group 2: caries excavated with rotary method, Group 3: caries excavated with Carisolv, and Group 4: caries excavated with Papacarie. Group 5 (negative control) consisted of 5 sound molars. After caries excavation, all specimens were longitudinally sectioned into two halves mesio-distally; one-half was used for chemical (EDX) and morphological analysis; while the remaining half was used for microhardness testing. RESULTS: The EDX analysis showed no significant difference in Ca wt%, P wt% and Ca/P ratio among Groups 2 to 5. The microhardness test showed that the Vickers hardness of dentin from Groups 3 and 4 was significantly lower (p<0.05) than for Groups 2 and 5. The morphological evaluation revealed that the use of Papacarie resulted in a dentin surface without a smear layer and patent tubules, while the usage of Carisolv resulted in a dentin surface exhibiting two patterns; the first showed the presence of a smear layer, while the other pattern showed partial smear layer formation. CONCLUSION: The results showed that papain-based chemomechanical caries removal method is a reliable alternative to rotary and NaOCl-based excavation of carious tissue.