Diagnosing cracked teeth is often not a simple decision, and no efficient clinical methods exist to predict their prognosis. This problem is exacerbated in cracked teeth that require root canal treatment before restorative procedures are undertaken, such as the placement of crowns. But little reported evidence-based information exists regarding the prognosis and survival of endodontically treated cracked posterior teeth, a major hindrance to the creation of adequate treatment plans. Olivieri et al from Universitat Internacional de Catalunya, Spain, conducted a systematic review and meta-analysis of the available evidence to determine the success and survival rates of endodontically treated cracked posterior teeth and to assess what, if any, preoperative factors affect tooth survival.

The authors searched 3 large databases, along with gray literature and article reference lists, to find articles reporting survival and success rates for endodontically treated permanent posterior cracked teeth with a follow-up period of ≥1 year. After screening 61 publications, they found 7 studies, all longitudinal cohort studies published between 2006 and 2018, that met the inclusion criteria. Because so few studies included outcome data for >1 year, the only data included in the analyses were those recorded at 1 year.

The survival rate at 1 year for the 674 teeth included in the 7 studies was 88%; the success rate for the 424 teeth in the 3 studies that reported success rates was 82%. These rates are similar to those following primary root canal treatment in noncracked teeth.

Preoperative variables, including patient sex, tooth type (molar or premolar), number of cracks, presence of a periodontal pocket, pulp status (vital or necrotic) and whether the cracked tooth was a terminal tooth, were also analyzed for their impact on outcomes. Although fatigue resistance decreases in the den-tin of older patients, and some studies have found a correlation between age and cracked teeth, the 4 studies in this review that included older patients failed to uncover any difference in survival rates for patients aged ≥50 years. The presence of a periodontal pocket increased the risk of extraction by 11%, while teeth without periodontal pockets had a survival rate of 97%, results parallel to those found in teeth without cracks; no other preoperative variable had any significant impact on outcome.

Conclusion

The results of this meta-analysis suggest that root canal treatment in cracked posterior teeth is a viable treatment option, especially in teeth without periodontal pockets.

Olivieri JG, Elmsmari F, Miró Q, et al. Outcome and survival of endodontically treated cracked posterior permanent teeth: a systematic review and meta-analysis. J Endod 2020;46: 455-463.