Spectrophotometric analysis of the effectiveness of different dentin tubule occlusion techniques in preventing discoloration caused by photosensitizers used in photodynamic therapy.

Aim: The efficacy of Copal Varnish (CV), dentin bonding agent (DBA), Nd:YAG laser and Er:YAG laser, which occludes dentin tubules by different mechanisms, was investigated in order to prevent unwanted coloration caused by methylene blue (MB) and phthalocyanine used in photodynamic therapy (PDT).

Materials And Methods: 165 upper incisors included in the study. Root canals were prepared up to 30/0.