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Updated: Jan 27, 2026

Development of a Direct Pulp-capping Model for the Evaluation of Pulpal Wound Healing and Reparative Dentin Formation in Mice
Published on: January 12, 2017
Hard tissue barrier detection in permanent mandibular molars that have undergone direct pulp capping and partial
Boonchanit Nophachatsathid1, Papimon Chompu-Inwai1, Chanika Manmontri1
1Division of Pediatric Dentistry, Department of Orthodontics and Pediatric Dentistry, Faculty of Dentistry, Chiang Mai University, Chiang Mai, Thailand.
Background/Purpose:
The presence of a hard tissue barrier (HTB) is commonly considered as a reliable indicator of a successful vital pulp therapy (VPT). This study therefore aimed to evaluate the probability of HTB detection over time, identify factors affecting HTB detection, and compare the mean time of HTB detection across subgroups.
Materials And Methods:
This retrospective cohort study included permanent mandibular molars that had undergone VPT. The examiners detected the HTB by comparing the follow-up with the immediate postoperative bitewing radiographs. A flexible parametric survival analysis was conducted to assess the probability of HTB detection over time and its associated factors. The restricted mean survival time was used to compare the mean time of HTB detection across subgroups.
Results:
This study included 149 radiographs of 70 teeth from 67 patients. The mean follow-up was 20.7 ± 14.7 months. The probability of HTB detection increased over time, reaching 0.75 (95 % confidence interval: 0.61-0.87) at 48 months, and was significantly greater in teeth treated with partial pulpotomy (PP) or with pre-operative periapical lesions. The mean time of HTB detection was significantly earlier after PP than direct pulp capping (20.03 vs. 36.50 months, P = 0.003), for teeth with than without periapical lesions (17.84 vs. 28.89 months, P = 0.021), and for teeth with incomplete than complete root formation (22.34 vs. 31.45 months, P = 0.031).
Conclusion:
The probability of HTB detection increased over time and was influenced by VPT type, periapical lesion status, and root formation status.
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