Failure Patterns of Severely Compromised Endodontically Treated Anterior Teeth: A Comparative In Vitro Study of Two Restorative Approaches

This in vitro study aimed to compare the failure patterns of two restorative techniques in severely damaged, endodontically treated maxillary central incisors: (1) endocrowns fabricated from lithium disilicate ceramic (IPS e.max Press), and (2) quartz-fiber posts with composite resin cores and lithium disilicate crowns (IPS e.max Press).

Twenty freshly extracted human maxillary central incisors with intact roots, comparable in length, morphology, and size, were selected. The teeth were randomly allocated into two groups (n = 10): Group I, restored with lithium disilicate endocrowns (IPS e.max Press), and Group II, restored with quartz-fiber posts, composite resin cores, and lithium disilicate crowns (IPS e.max Press).

Specimens were mounted and tested using a universal testing machine. A compressive load was applied at a 45° angle to the middle third of the palatal surface at a crosshead speed of 0.5 mm/min until failure occurred. Failure patterns were recorded and analyzed using SPSS software (version 13).

Statistical analysis revealed no significant differences in the distribution of failure patterns between the two groups (p > 0.05, 95% confidence level).

This study compared endocrowns and post-and-core restorations for endodontically treated maxillary central incisors. Both techniques showed comparable fracture resistance, with failure modes differing mainly in location and repairability. Endocrowns demonstrated favorable outcomes due to their minimally invasive design and improved stress distribution. These findings support endocrowns as a conservative alternative while confirming that both approaches can provide clinically acceptable performance.

Within the limitations of this in vitro study, endocrowns fabricated from lithium disilicate (IPS e.max Press) exhibited failure patterns comparable to those of the conventional technique involving quartz-fiber posts, composite cores, and lithium disilicate crowns when restoring severely compromised endodontically treated anterior teeth.