A Study Of Canal Morphology Of Mandibular First Premolar By Using Cone-beam Computed Tomography

Objective:Endodontics and periapical diseases are two common diseases against human oral health.Root canal therapy is the treatment of dental pulp periapical disease the most effective method.Its principle is the source of infection in the eradication of root canal system,put an end to the reinfection.Correct understanding of root canal morphology and its change can ensure that the curative effect of root canal treatment to achieve the ideal.Mandibular first premolars anatomic structure of the root canal system is complicated,is one of the most difficult treatment of teeth.Therefore,to understand the mandibular first molar root canal system is very important.This study use of CBCT on the mandibular first premolar root canal system to study the anatomical form and understand that the anterior mandibular first molar root canal anatomy,and root canal of mandibular first premolars types are classified,for clinical diagnosis and treatment of morphological structure of root canal system significant information.Methods:This study choose dental clinic in Shanxi Dayi Hospital from October 2014 to September 2014 the various causes to our department for patients during the period of CBCT digital images of 498 cases as the research object。Remove root development,has a root canal,unfinished crown filling body or restoration,root canal calcification absorption,root damage,image blur after mandibular first premolars,screen can be incorporated into the research scope of the mandibular first premolars.Stored in patients with the information such as name,gender,age,tooth bit,observe and record all of the mandibular first premolars CBCT scan data:(1)the number of root canal;(2)the mandibular first premolars one-third in the root canal orifice,root number,and apical third root canal;(3)the root canal morphology is symmetric.(4)record the root tube type.The above information is fully informed patient,and have got the patients’ informed consent.Results:996 single root in mandibular first premolars rate is 96.48%,double tooth root with low detection rate of 3.52%.75.21% of teeth for single tube,the remaining 21.27% of the multiple root canal.The incidence of number of root and root canal in the left and the right of the differences were not statistically significant.According to Vertucci taxonomy which type I most see more,accounted for 75.20%,the incidence of V type,at 21.97%,the rest of the incidence of each type of a total of 2.83%(0.56% 0.56% type II,III,IV 0.42%,0.10% type VI,VII,0.20%).There are 10.74% of a total of 107 teeth root surface sag,and are located in the root surface sag of mesial lingual,see more in the twin-root canal(90),single canal only 17.88.55% of the 498 cases of image data have the same root tube type.Conclusion:Mandibular first premolars majority of only a root canal,but the occurrence of double root canal also nots allow to ignore,most of them have type 1 or 2 anatomical features.Its root is usually located in the root of mesial lingual surface concave,careful exploration should be paid attention to during root canal therapy root canal number,avoid excessive cutting root tube wall.Mandibular first premolar root canal types are symmetrical,but there are still a part of patients with left and right lateral root canal anatomical configuration is not completely consistent,to avoid omission root canal in clinical work.Clinicians should fully recognize when to treat mandibular first premolars anatomical morphology variation characteristics of root canal system,in order to improve the success rate of treatment.Use of CBCT auxiliary examination could help to determine the root canal anatomy morphology variation,is difficulty in the diagnosis and treatment of root canal to provide more accurate information.