Restoration of teeth lacking complete ferrules using cast precious metal alloy post-and-cores and knife-edged crowns:...

While the presence of a ferrule has been reported to be essential for post-and-core restorations, many extensively damaged teeth lack complete ferrules. The outcome of post-and-core restorations for these teeth remains uncertain.

The purpose of this retrospective clinical study was to assess the outcome of cast alloy post-and-cores and knife-edged crowns for the restoration of teeth lacking complete ferrules.

A total of 106 participants with endodontically treated teeth with 2 or fewer walls with ferrules who had received cast precious metal alloy post-and-cores along with knife-edged crowns between 2013 and 2022 were recalled for a clinical examination. The minimum follow-up time was 5 months after restoration, and restoration failure and the periodontal status difference between restored teeth and reference teeth were determined. Kaplan-Meier analysis was performed to obtain success curves. The influence of age, sex, jaw position, tooth type, and antagonistic dentition upon the success function was analyzed with the log-rank or Breslow test (α=.05).

A total of 100 participants with 130 restorations were studied. The success rate of the restorations was 93.85% in a mean ±standard deviation period of 48.3 ±26.1 months. The estimated 5-year cumulative success probability was 91.61%. No significant effect on the success of restorations was found regarding age, sex, jaw position, tooth type, or antagonistic dentition (P>.05). The main failure types were post debonding, root fracture, and apical periodontitis. No statistical difference in tooth mobility (Z=-1.265, P=.206) was found between the restored and the reference teeth, but the plaque index and calculus index of the restored teeth were significantly lower than of the reference teeth (Z=-7.216, P<.001; Z=-7.044, P<.001). Teeth that had received cast post-and-cores and knife-edged crowns were found to have no significant correlation with periodontal disease (χ²=1.131, P=.288) or bleeding on probing (χ²=3.436, P=.064).

The clinical outcomes for the restoration of teeth with 2 or fewer walls with ferrules using cast precious metal alloy post-and-cores and knife-edged crowns were favorable, exhibiting a high 5-year cumulative success probability and no increased periodontal health risk.