Value Of Using Cone Beam Computer Tomography In Root Canal Treatment

Objective:(1) Observe and learn root canal anatomical morphology and the classificationoccurring in mandibular anterior teeth and mandibular first premolarrespectively through the Cone Beam CT (CBCT). Enhance the understandingof the situation and variation mandibular anterior teeth and mandibular premolarroot canal system occurs.(2) Assess the agreement between periapical radiographs (PA) and cone-beamcomputed tomography (CBCT) for quality of the root filling, and to explore theadvantage and application value of CBCT in the root canal treatment.(3) Evaluate the quality of clinical root canal filling, and to investigate factors thataffect root canal filling effect.Method:(1) Randomly selected cases because of planted, impacted teeth extracted, orthodontictreatment, root canal therapy and other complex reasons need to shoot CBCTimaging data from2012to2013in our department. A total of78patients with284mandible anterior teeth and108mandibular first premolars were collected.Observe and record the incidence of mandibular anterior teeth and mandibularpremolar root canal morphology, the number and type of root canal according tocriteria from Vertucci and Wu classification using CBCT.(2) In total,100teeth (221canals) were clinically diagnosed and received root canaltherapy. The patient’s age, gender, teeth and the number of clinic visits wererecorded. After the roots filled, the length and density of root filling were assessedwith PA and CBCT simultaneously by two experienced endodontists. Chi-squaretest was performed on the data from PA or CBCT to evaluate the quality of theroot filling.(3) Evaluate the quality of clinical root canal filling through the CBCT image data,and to analysis the possible factors that affect root canal filling effect.Results:(1)106mandibular central incisors were collected. Single-canal type has the most,there were77cases accounts for about72.64%, double-canal type have28casesaccounts for26.41%;104mandibular lateral incisor were collected, single-canaltype has75cases in total accounting for72.12%, double-canal type have29casesaccounts for27.88%;104mandibular canine were collected, single-canal has74cases accounted for71.15%, double-canal type has30cases, accounting for28.85%;108mandibular premolars were collected, single-canal has72cases accounted for66.67%, double-canal type has32cases, accounting for29.63%.Three-canal type has1case accounting for0.93%, C-type root canal has3casesaccounted for2.78%.(2)214canals have been root-canal treatment while7canals have been missed. Onthe aspect of length, density and satisfactory of the root filling, there were about34.58%,30.48%and37.58%of canals having disagreement based on theevaluation from PA and CBCT respectively. According the result of statistical test,PA and CBCT have highly significant difference (P<0.01) on the assessment ofthe three aspects mentioned before.(3) There were15satisfying root canal filling cases (55.56%) in27cases of frontteeth. Meanwhile, there were16satisfying root canal filling cases (53.33%) in30cases of premolars. And there were9satisfying root canal filling cases (20.93%)in43cases of molars. According to the result from single factor analysis, vitalpulp and front teeth have the higher ratio of satisfactory.Conclusion:(1) Root canal morphology of mandibular anterior teeth and mandibular molars aremore complex and perform diversity. CBCT has the good accuracy to observe rootcanal shape, which can help clinicians understand the occurrence of root canalmorphology and occurrence of variation.(2) It is more sensitive and accurate for CBCT in detecting the quality of the rootfilling compared with PA, which has high value in applying in the complex ordifficult root canal treatment.(3) The rate of flush root canal filling declined from the group of front teeth to molars.The short root filling performed the highest in the group of premolars. The groupof molars had the highest rate of void occurrence while front teeth had lowest. Themost satisfying root canal filling were the group of front teeth, and the mostunsatisfying filling happened in molars; the condition of pulp and tooth positionhas a significant impact on the effect of root canal filling (P <0.1).