Prevalence of Four Canals in the Mandibular First Molars of Dental Patients in Chaiyaphum Province - ความชุกของฟันกรามล่างแท้ซีแรกทีมี 4 คลองราก ของผู้ป่วยทันตกรรม จังหวัดชัยภูมิ

Abstract

                 The objective of this descriptive study was to evaluate the prevalence of three roots and four root canals in the mandibular first molars of dental patients in Chaiyaphum province. It was conducted by (1) clinical record review and examiniation of radiographs among patients receiving root canal treatment of mandibular first molars at Chaiyaphum hospital during the period from May 2006 -April 2014 and (2) examining dental patients undergoing mandibular first molars extraction at participat-ing hospitals and clinics in Chaiyaphum province during March - June 2014 using a clearing technique. It was found that among 250 clinical records of cases with mandibular first molars who received root canal treatment, 8.0% of mandibular first molars had three roots and 39.6% of them had four root canals. The extra-root canal could be found in distal root. As for the clearing technique among 134 patients with mandibular first molars extraction, the prevalence of three–rooted mandibular first molars was 12.7%, and 52.9% of examined teeth had four root canals (two mesial and two distal). It was recommended that, with high frequency of a fourth canal in mandibular first molar of dental patients in Chaiyaphum province, it is essential to always look for a second canal in the distal root during endodontic treatment.

Key words: mandibular first molar, anatomical variation, four dental root canals