Abstract:

Objective To investigate the clinical efficacy of onlays and modified inlay-crowns in the restoration of posterior tooth defects. Methods A total of 190 patients(involving 206 crowns) with posterior teeth that required restoration of tooth defects after root canal therapy were collected from the Affiliated Stomatological Hospital of Nanjing Medical University between May 2021 and May 2023. They were divided into two groups based on the tooth defect restoration method: the onlay group (102 crowns) and the modified inlay-crown group (104 crowns). Twelve months later, the restoration efficacy of the affected teeth in both groups was evaluated, and the incidence of restoration adverse events and patient satisfaction were compared between the two groups. Results Twelve months after the restoration of the affected teeth in both groups, the overall rate of achieving Grade A according to the modified United States Public Health Service(USPHS) criteria in the onlay group was lower than that in the modified inlay-crown group. There were no statistically significant differences in the Grade A rates regarding restoration marginal adaptation, restoration integrity,secondary caries,gingival health status and presence of food impaction between the two groups(P>0.05). The total incidence of adverse events in the onlay group was 11.96%, which was higher than the 3.06% in the modified inlay-crown group, and the difference was statistically significant(P<0.05). In terms of follow-up patient satisfaction, the total satisfaction rate was 87.5% in the onlay group, lower than the 93.33% in the modified inlay-crown group, but the difference was not statistically significant(P>0.05). Conclusion The short-term clinical efficacy of modified inlay-crowns in the restoration of posterior tooth defects is superior to that of onlays. Modified inlay-crowns can achieve good patient satisfaction and are an effective restoration method.

Key words: onlay, modified inlay, CAD/CAM, clinical effect