This study aimed to assess the clinical efficacy of selective caries removal and complete caries removal for the management of deep carious lesions proximal to the pulp in permanent teeth.

Fifty-two patients presenting with deep caries in permanent teeth (affecting a total of 52 teeth) were recruited from the Department of Endodontics at the Affiliated Stomatological Hospital of Anhui Medical University between October 2021 and October 2023. A random number table method was utilised to divide each of the 26 cases (26 affected teeth) into an observation group (selective caries removal group) and a control group (complete caries removal group). Dental surgical microscopy was employed for precise tooth removal in both groups. Depending on pulp exposure following caries removal, either iRoot BP Plus or TheraCal LC was utilized for direct or indirect pulp capping. Flow resin was applied for dentin layer sealing, followed by cavity filling with 3M composite resin. A Chi-squared test was employed to ascertain whether there was a significant difference in the rate of intraoperative pulp exposure of the affected teeth between the two groups. An independent samples t-test was used to compare the pain levels of the patients in the two groups at one week postoperatively. A comparison of the postoperative complications of the patients in the two groups at the 6-month postoperative follow-up was conducted using Fisher′s exact test. Per-protocol and intention-to-treat analysis were conducted to evaluate the success rate of the affected teeth in both groups at the 6-month postoperative interval.

The intraoperative pulp exposure rate in the selective caries removal group (0%) was significantly lower than that in the complete caries removal group (30.77%), and the difference was statistically significant (P = 0.004). The visual analogue score (VAS) of pain in the selective caries removal group at 24 hours postoperatively was (2.9±0.7), which was significantly lower than that in the complete caries removal group (3.3 ± 0.6). The difference was statistically significant (t = 2.120, P = 0.039). The postoperative complications in the selective caries removal group (two cases of pulpitis) were statistically comparable with those in the complete caries removal group (one case of apical periodontitis and two cases of pulpitis) (P = 0.369). The per-protocol analysis revealed that the success rates were high for both the selective caries removal group (91.30%) and the complete caries removal group (87.50%), with no statistically significant difference (RR_{excluding lost follow-up} = 0.696, 95% CI_{excluding lost follow-up}: 0.128 to 3.790, P_{excluding lost follow-up} = 0.675). The intention-to-treat analysis showed that the success rates for the selective caries removal group were 80.77% and 92.31%, and for the complete caries removal group, they were 80.77% and 88.46%, respectively. The differences were not statistically significant (RR_{all lost follow-up considered as failure} = 1.000, 95% CI_{all lost follow-up considered as failure}: 0.328 to 3.047, P_{all lost follow-up considered as failure} = 1.000; RR_{all lost follow-up considered as success} = 0.667, 95% CI_{all lost follow-up considered as success}: 0.121 to 3.666, P_{all lost follow-up considered as success} = 0.641) .

Selective caries removal presented a lower risk of pulp exposure, entailed minimal invasiveness, resulted in fewer postoperative complications, and yielded higher success rates compared to traditional complete caries removal technique. Therefore, its promotion and application were recommended for treating permanent teeth with deep caries proximal to the pulp.