Root Canal Treatment Outcome and Restorative Condition of Teeth Treated by Undergraduates—A Clinical and Radiographic Evaluation

Background: The aim was to evaluate the nonsurgical Root Canal Treatment (nRCT) outcome, the restorative condition and the relationship between the coronal restoration quality and the outcome of teeth endodontic treated by undergraduates at the University of Caxias do Sul School of Dentistry (UCS-SD), Brazil, between 2019 and 2021. Materials and Methods: Data from the endodontically treated cases were retrieved, and the patients were recalled for a follow-up appointment at the university. The endodontic diagnosis, radiographs, and the presence of definitive restorations were analyzed in the clinical records. During the follow-up appointment, endodontically treated teeth were classified as present or absent. The nRCT was classified as successful (complete or incomplete healing) or failure (uncertain or unsatisfactory healing). Coronal restoration was classified as absent or present. When it was present, it was classified as permanent or temporary, and its quality as adequate or inadequate restoration. The results were presented as percentages. Results: A total of 257 teeth were endodontically treated. The most prevalent diagnosis was Chronic Apical Periodontitis (33.33%) and the most commonly treated teeth were premolars (46.15%). A total of 52 (21%) treated teeth were clinically and radiographically reexamined. The success rate for the nRCT was 98.08%. About 61.54% of this sample had a definitive composite resin restoration. Conclusion: The nRCT success rate was high. Special attention should be given to the presence and quality of the definitive restoration. Clinical Implications: There was no statistically significant impact between the coronal restoration and the nRCT success (P > 0.05).

Effect of acid etching on marginal adaptation of mineral trioxide aggregate to apical dentin:microcomputed tomography and scanning electron microscopy analysis

The present investigation assessed the effect of acid etching on marginal adaptation of white- and gray-colored mineral trioxide aggregate （MTA） to apical dentin using microcomputed tomography （micro-CT） and scanning electron microscopy （SEM）. Sixty-four extracted single-rooted human maxillary teeth were used. Following root-end resection and apical preparation, the teeth were equally divided into four groups according to the following root end filling materials： （i） white-colored MTA （WMTA）, （ii） etched WMTA （EWMTA）, （iii） gray-colored MTA （GMTA） and （iv） etched GMTA （EGMTA）. After 48 h, the interface between root-end filling materials and the dentinal walls was assessed using micro-CT and SEM. Data were statistically analyzed using the KruskaI-Wallis and Dunn tests. Micro-CT analysis revealed gap volumes between the apical cavity dentin walls and EGMTA, GMTA, EWMTA and WMTA of （0.007 1±0.004） mm3, （0.053±0.002） mm3, （0.003 6±0.001） mm3 and （0.005 9±0.002） mm3 respectively. SEM analysis revealed gap sizes for EGMTA, WMTA, EWMTA and GMTA to be （492.3±13.8） μm, （594.5±17.12）μm, （543.1±15.33） μm and （910.7±26.2）μm respectively. A significant difference in gap size between root end preparations filled with GMTA and EGMTA was found （P〈O.05）. No significance difference in gap size between WMTA and EWMTA were found in either SEM or micro-CT analysis. In conclusion, pre-etching of apical dentin can provide a better seal for GMTA but not for WMTA.