Design and implementation of a hybrid genetic algorithm and artificial neural network system for predicting the sizes of unerupted canines and premolars.

The aim of this study was to develop a novel hybrid genetic algorithm and artificial neural network (GA-ANN) system for predicting the sizes of unerupted canines and premolars during the mixed dentition period. This study was performed on 106 untreated subjects (52 girls, 54 boys, aged 13-15 years). Data were obtained from dental cast measurements. A hybrid GA-ANN algorithm was developed to find the best reference teeth and the most accurate mapping function. Based on a regression analysis, the strongest correlation was observed between the sum of the mesiodistal widths of the mandibular canines and premolars and the mesiodistal widths of the mandibular first molars and incisors (r = 0.697). In the maxilla, the highest correlation was observed between the sum of the mesiodistal widths of the canines and premolars and the mesiodistal widths of the mandibular first molars and maxillary central incisors (0.742). The hybrid GA-ANN algorithm selected the mandibular first molars and incisors and the maxillary central incisors as the reference teeth for predicting the sum of the mesiodistal widths of the canines and premolars. The prediction error rates and maximum rates of over/underestimation using the hybrid GA-ANN algorithm were smaller than those using linear regression analyses.

Comparison of electrosurgical pulpotomy with zinc oxide eugenol or zinc polycarboxylate cements sub-base.

PURPOSE: The aim of this study was to compare the clinical and radiographic success rates of electrosurgical pulpotomy of human primary molars with zinc oxide eugenol (ZOE) and zinc polycarboxylate (ZPC) cements. METHODS: In this randomized clinical trial study, 120 primary second molar teeth were treated by electrosurgical pulpotomy. Teeth were randomly assigned to two groups according to whether ZOE or ZPC cement was used as a sub-base. Teeth were restored with stainless steel crowns and were evaluated clinically and radiographically after 3, 6, and 12 months by two independent examiners. Clinical treatment outcomes and radiographic findings were statistically analyzed using Fishers' exact test with statistically significant differences defined for P < 0.05. RESULTS: At 12 months, the clinical and radiographic success rates in the ZOE group were 98.2% and 84.2% and in the ZPC group were 96.2% and 75%, respectively (P > 0.05 for all). CONCLUSIONS: The outcomes of this study suggested that either ZPC or ZOE sub-base have similar clinical and radiographic success in electrosurgical pulpotomy.