[Twoyear outcomes and the influence factors of indirect pulp treatment in primary teeth: a retrospective study].

OBJECTIVE: To evaluate the outcomes and to find out the influence factors of indirect pulp treatment in primary teeth.
METHODS: Children who received indirect pulp treatment in primary teeth in the Department of Pediatric Dentistry in Peking University School and Hospital of Stomatology from August, 2014 to September, 2016 were collected in the Electronic Medical Record Database of Peking University School and Hospital of Stomatology, via the database for scientific research provided by the corporation of Kaientai. The children selected as the subjects of this study were followed up over 1.5 years, and they were under 9 years old if in the group of primary molars while the children in the group of primary anterior teeth were under 4 and a half years old. Those children who were not reviewed regularly or didn't have complete medical records were removed. Basic information, the relevant medical records and radiographic records of those children were collected. All teeth were examined clinically and classified into 2 outcomes, teeth in group H were regarded as succeeded, and teeth in group P were regarded as failed. Survival analysis was applied. The survival rate and survival time of the deciduous teeth calculated. Multivariate analysis was performed by using Cox proportional hazard model.
RESULTS: One hundred and six children were finally included, aged from 1.6 to 8.8 years, with the mean age of (5.0±1.7) years. 168 primary teeth (122 primary molars, 46 primary anterior teeth) were included, and the average follow up time was (729±244) days. Thirty-five primary teeth (23 primary molars, 12 primary anterior teeth) failed upon clinical or radiographic examinations by September, 2018. The cumulative survival probability of half a year, one year, one year and a half, two years, two and a half years for the indirect pulp treatment was 93.5%, 92.9%, 87.5%, 82.7%, and 75.5% through the KaplanMeier method, respectively. Through the analysis of Cox proportional hazard model, in primary molars, the survival probability tended to be lower when the number of tooth surface affected by caries was greater (OR=1.709, P<0.05). Compared with primary molars, the survival probability of primary anterior teeth was lower, but the difference was not significant.
CONCLUSION: Complying the current instructions in our department, the cumulative survival probability of two and a half years after the indirect pulp treatment in primary teeth was 75.5%. In primary molars, the survival probability tended to be lower when the number of tooth surfaces affected by caries increased.