Predicting pulpectomy success and its relationship to exfoliation and succedaneous dentition

This study evaluated factors that affected pulpectomy (PE) success and its effect on the succedaneous tooth's eruption and enamel formation. Sixty-five of 250 patients with PEs met the selection criteria and yielded 81 zinc oxide-eugenol PEs (30 incisors, 51 molars) followed a mean time of 90.8 months. Overall PE success was 77.7% with no difference between molars and incisors (P = 0.53). Enamel defects were observed in 18.7% of succedaneous teeth and were related (P = 0.005) to the pre-existing infection causing excess root resorption (>1 mm preoperative root resorption = 44.4% defects) but were not related to overretention of ZOE filler (P = 1) or length of fill (P = 0.36). The PE procedure was not related to causing succedaneous tooth defects since teeth replacing PEs showed no significant increase in the incidence of defects compared with untreated contralateral controls (P = 0.99). There was a 20% incidence of succedaneous tooth anterior cross-bite or palatal eruption following incisor PEs and 21.6% ectopic eruption of premolars following primary molar PEs. Most PEs (95.9%) were lost at their normal exfoliation time or earlier, but 35.8% needed extraction due to overretention by soft tissue at the time of shedding. Pulpectomy success rates showed that the most important preoperative predictor was the amount of primary tooth root resorption. Greater than 1 mm of root resorption resulted in only a 23.1% success rate, which was significant (P = 0.001). Pulpectomies filled short or to the apex had a significantly greater success (P = 0.011) than long fills. Pulpectomies correctly done do not appear to contribute to adverse effects on succedaneous tooth formation but have a 20% chance of altering the path of permanent tooth eruption.