Full-coverage Porcelain-fused-to-metal Crown with Guided Access for Future Endodontic Treatment: A Comparative Pilot In Vitro Study.

Abstract

Aim: This pilot study introduces a novel design concept for full-coverage porcelain-fused-to-metal (PFM) crowns, incorporating guided access features to facilitate future endodontic treatment and overcome difficulties associated with access cavity preparation through crowns.

Materials and methods: This in vitro study utilized 24 extracted molars (removed for periodontal reasons), divided into three groups: Group I (control) comprised natural teeth (n = 6); group II received conventional PFM crowns (n = 8); and group III (experimental) received guided PFM crowns (n = 10). The guided crown design involved preparing the teeth for standard PFM crowns, followed by taking a periapical X-ray to visualize the mesiodistal view and identify the pulp chamber. A mark was placed on the occlusal surface of the prepared tooth opposite the pulp chamber, and the technician replicated this mark on the crown during fabrication. A single general dentist prepared the access cavities for all groups, and two endodontists evaluated the samples based on three parameters: (a) time required for access cavity preparation, (b) quality of the access cavity, and (c) size of the access cavity. Data were analyzed using Statistical Package for Social Sciences software, with statistical significance set at p < 0.05.

Results: The time required to reach and clean the pulp chamber was significantly different among the three groups (p = 0.011), with the guided PFM group taking less time than the conventional PFM group (7.63 ± 2.19 minutes compared to 11.52 ± 2.65 minutes), and no significant differences were noted between natural teeth and the experimental group (p = 1.000). Regarding the quality of the access cavity, it was acceptable among all three groups with no significant difference (p = 0.537), while the size of the access cavity in the guided PFM group was bigger than the other two groups with no significant difference.

Conclusion: The guided PFM crown showed promise as a potential replacement for conventional PFM crowns, offering a faster and safer approach to root canal treatment.

Clinical significance: This pilot study introduces a novel guided PFM crown design that reduces the time required for access cavity preparation while maintaining the quality of the access cavity comparable to natural teeth. The guided PFM crown offers a practical and cost-effective solution for clinicians, particularly in settings where advanced digital technologies like cone beam computed tomography (CBCT) and computer-aided design/computer-aided manufacturing are unavailable. How to cite this article: Mashyakhy M, Adawi H, Abu-Melha A, et al. Full-coverage Porcelain-fused-to-metal Crown with Guided Access for Future Endodontic Treatment: A Comparative Pilot In Vitro Study. J Contemp Dent Pract 2025;26(3):234-238.