An investigation of accessory canals in primary molars – an analytical study

AIM: To evaluate the number, anatomical morphology and patency of accessory canals in the furcation of carious primary molar teeth and to ascertain whether these anatomic variations contribute to endodontic infection. DESIGN: The accessory canals were observed under radiovisiography or RVG (Phase 1), scanning electron microscopy or SEM (Phase 2) and light microscopy (Phase 3). RESULTS: The prevalence of accessory canals was 34.3% with a mean ± SD of 0.73 ± 0.980 in Phase 1, 73.3% with a mean ± SD of 3.07 ± 3.151 in Phase 2 and 64.3% with a mean ± SD of 1.68 ± 2.405 in Phase 3. The results observed were Phase 1 vs Phase 2<0.001 (highly significant), Phase 1 vs Phase 3 0.110 (ns) and Phase 2 vs Phase 3<0.001 (highly significant) employing Wilcoxon signed-rank test. The canals were predominantly oval in shape and ranged from 1 μ to 225 μ in diameter. Only 7% canals were observed to be patent. CONCLUSIONS: Accessory canals may not be the primary cause of transmission of infection in the inter-radicular area of primary molars. Other factors enhancing permeability of the pulpal floor may be of more significance and need evaluation on a larger scale.