Abstract
AIM: To compare fracture resistance (FR) of IPS e.max computer-aided design (CAD) and press endocrowns with different preparation depths (2 and 5 mm) and crowns retained by post and core.
MATERIALS AND METHODS: Thirty-six intact maxillary central incisors were utilized. Teeth were categorized into two primary groups (n = 18) according to the material fabrication technique; A: Computer-aided design/computer-aided manufacturing (CAD/CAM) technique and, B: Pressing technique, with each group then separated into three subgroups (n = 6); S1: Crown supported by post and core, S2: Long endocrown with a depth of 5 mm, and S3: Short endocrown with a depth of 2 mm. Restorations were luted using resin cement and subjected to thermocycling (5,000 cycles), followed by FR test. Data were gathered and subjected to statistical analysis utilizing a two-way analysis of variance test.
RESULTS: Results indicated that IPS e.max CAD exhibits superior FR than IPS e.max press across all configurations. The FR variations among designs for each material individually indicated that, within the CAD group, FR increased gradually from S1 to S3 (S1: 473.8 ± 22 ≤ S2: 608.6 ± 38.7 ≤ S3: 713.3 ± 22.5). In the press group, a notable disparity was observed, however with a distinct pattern: S1 (418.9 ± 5.6) exhibited lesser FR than both S2 and S3 (437 ± 5.7 ≤ 477.1 ± 28.1, respectively).
CONCLUSION: All groups showed clinically accepted FR results. Restorations fabricated by CAD/CAM technique showed a higher FR than those fabricated by pressing technique. Endocrowns showed a higher FR than full-coverage crowns held by post and core.
CLINICAL SIGNIFICANCE: For clinicians, using IPS e.max CAD anterior endocrowns with short depth (2 mm) could present a practical treatment modality to the traditional crowns held by post and core for restoration of endodontically treated maxillary central incisors. How to cite this article: Ahmed DH, Amgad SW, Bakry AM. Effect of Preparation Depth on Fracture Resistance of Anterior Teeth Restored by Endocrowns and Post-retained Crowns - In Vitro Study. J Contemp Dent Pract 2025;26(5):504-511.