EC Dental Science

Objectives: Rehabilitation of endodontically treated teeth with extensive coronal damage is nevertheless difficult due in part to the weakening of the dentin tissues that surround pulp removal. There is a lack of data on the long-term survival and success of endocrowns in comparison to conventional crowns. To compare the fracture strength, survival rate, and success rate of endocrowns to those of conventional restoration is the aim of this systematic review and meta-analysis.

Data: We included all studies comparing endocrowns and conventional restoration in endodontically treated teeth whether premolar or molar ones. We included invitro studies, randomized controlled trials (RCTs), case-control, and cohort studies. We excluded studies that don’t compare endocrowns to conventional restorations, in addition to reviews, case reports, and case series. We also excluded finite element analysis studies.

Sources: We searched the three databases (PubMed, Web of Science, and Scopus) for articles investigating our aim.

Study Selection: Two authors working independently carried out the process of title-abstract screening followed by full-text screening to include the eligible articles. Any difference was resolved between them and if the conflict persists, a senior author was in charge of it.

Results: Endocrown group was associated with a higher fracture strength compared to the conventional restoration group with a mean difference of 145.7 Newton, 95%CI: (23.86, 267.54, p = 0.02). The overall survival rate for endocrowns was 83.6% (88% for molars, and 75% for molars), while that of the conventional restoration was 80% (87% for molars, and 71.4% for premolars). However, no significant difference was obtained between both groups with an overall OR of 1.39, 95%CI: (0.76, 2.55, p = 0.29). The overall success rate for endocrowns was 81.4% (82.2% for molars, and 75% for premolars), while that of conventional restorations was 86% (83.2% for molars, and 95% for premolars) with no statistically significant difference between both groups with overall OR of 0.8, 95%CI: (0.43, 1.48, p = 0.48).

Conclusion: Endocrowns are associated with better fracture strength when compared to conventional restorations in endodontically treated molar and premolar teeth. No difference between both methods regarding survival and success rates. However, more prospective RCTs with large sample sizes validate the current findings.

 Keywords: Conventional; Endocrown; Endodontics; Survival; Fracture

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