ABSTRACT
AIM: This study aims to compare intraradicular smear layer removal efficacy of different concentrations of glycolic acid (GA), 17% ethylenediaminetetraacetic acid (EDTA), and 10% citric acid (CA) as final rinses in the canals of curved mesial root of mandibular first molars using the specific irrigant protocols. MATERIALS AND METHODS: Fifty-eight mandibular first permanent molars with 15°-30° of curvature of the mesial roots were selected, standardized, mesiobuccal canal prepared using the rotary instrumentation. Sodium hypochlorite was used as initial rinse solution (8 ml). The samples were divided into control (n = 5) (I - Normal saline and II - 17% EDTA) and experimental groups (n = 8) (Groups III, IV, V, VI, VII, and VIII) based on the type of final rinse solution (5 ml) used, i.e. 2.5% GA, 5% GA, 10% GA, 17% GA, 37% GA, and 10% CA. Samples were split buccolingually, dehydrated, splutter coated, and examined under a scanning electron microscope. RESULTS: Group IV presented the least amounts of smear among the GA experimental groups at the apical, middle, and coronal one-thirds of the root canal with a mean value of 2.6 ± 1.012, and on comparison with Group II, the results were comparable, and no significant difference found statistically (P > 0.05). CONCLUSION: The use of GA as final rinse solution for biomechanical preparation during endodontic therapy seems promising. Further evaluation in a clinical setting is recommended.
ABSTRACT
AIM: This study aimed to analyze incidence of isthmus in human permanent mandibular first molar teeth using cone-beam computed tomographic imaging techniques in a South Indian population. MATERIALS AND METHODS: Three hundred permanent mandibular first molar teeth were collected, cleaned, and stored in normal saline. They were divided into groups (GPs) I and II based on number of roots, and were further subdivided (right and left [RL] subgroups A and B for GP I; and RL subgroups C and D for GP-II). Samples were processed and isthmus incidence was evaluated by cone-beam tomography, compared, and statistically analyzed. RESULTS: Overall in mandibular first molars, the isthmus incidence in mesial root was 97.2%, distal root was 39%, and distolingual root was 0%. There was no statistically significant difference between the right and left mandibular first molar teeth with regard to incidence of isthmus (P > 0.05). There was an incidence of type I (38.67%), type II (56.33%), type III (3%), and type IV (2%) isthmuses in mesial root and type I (12.33%), type II (16%), and type III (10.67%) in distal root. CONCLUSION: Incidence of isthmus was very high in the mesial root of the mandibular first molar and should be factored during nonsurgical and surgical endodontic treatment procedures to achieve successful treatment outcomes.
