Microcomputed tomography analysis of the radicular residual dentin thickness in mandibular second molars after virtual fiber post placement: Identification of danger zones.
J Prosthet Dent
; 130(1): 109.e1-109.e10, 2023 Jul.
Article
de En
| MEDLINE
| ID: mdl-37210223
ABSTRACT
STATEMENT OF PROBLEM:
Mandibular second molars have variable root, pulp chamber floor, and radicular groove morphologies, potentially affecting residual dentin thickness and post placement suitability. However, an identification of the danger zones is lacking.PURPOSE:
The purpose of this in vitro study was to investigate the residual dentin thickness in the danger zone of mandibular second molars after virtual fiber post placement by using a simulation method based on microcomputed tomography (µCT). MATERIAL ANDMETHODS:
A total of 84 extracted mandibular second molars were scanned using µCT and classified according to root morphology (separate or fused) and pulp chamber floor morphologies (C-shaped, non-C-shaped, or no pulp chamber floor). Fused-root mandibular second molars were further classified based on the radicular groove type (V-, U-, or Ω-shaped). All specimens were accessed, instrumented, and rescanned with µCT. Two types of commercial fiber posts were also scanned. Clinical fiber post placement was simulated in all prepared canals by using a multifunctional software program. The minimum residual dentin thickness of each root canal was measured and analyzed by using nonparametric tests to identify the danger zone. Perforation rates were calculated and recorded.RESULTS:
Larger fiber posts decreased minimum residual dentin thickness (P<.05) and increased perforation rate. In regard to mandibular second molars with separate roots, the distal root canal exhibited a significantly higher minimum residual dentin thickness than the mesiobuccal and mesiolingual root canals (P<.05). However, no significant difference in minimum residual dentin thickness was found between the different canals in fused-root mandibular second molars with C-shaped pulp chamber floors (P<.05). Fused-root mandibular second molars with Ω-shaped radicular grooves had a lower minimum residual dentin thickness than those with V-shaped radicular grooves (P<.05) and demonstrated the highest perforation rate.CONCLUSIONS:
The morphologies of the root, pulp chamber floor, and radicular groove were correlated with residual dentin thickness distribution in mandibular second molars after fiber post placement. A comprehensive understanding of mandibular second molar morphology is essential for determining the suitability of post-and-core crown restorations after endodontic treatment.
Texte intégral:
1
Collection:
01-internacional
Base de données:
MEDLINE
Sujet principal:
Racine dentaire
/
Mandibule
Type d'étude:
Diagnostic_studies
/
Prognostic_studies
Limites:
Humans
Langue:
En
Journal:
J Prosthet Dent
Année:
2023
Type de document:
Article