Importance of paired t-test in time-based comparison of obturation and sealbio techniques in root canal treatment

Dear Editor, We read an article in the May–June issue (2019) entitled “A Regenerative Approach for Root Canal Treatment of Mature Permanent Teeth: Comparative Evaluation with 18 months Follow-up” with great interest.1 This study has compared the conventional obturation and the SealBio techniques regarding the deposition of a biological barrier at the root apex by the stimulation of periradicular cells and it has been stated that there is no significant difference. However, comparing the techniques only with each other would not provide enough output in the decisionmaking process. Furthermore, the change depending on the effect of the same technique overtime should also be compared within itself. Therefore, we want to contribute to this issue.