Abstract
A morphologic and anatomic evaluation of furcation area in the upper and lower first molars
 Dr. V. Esfahanian* - Dr. M. Ketabi* - Dr. M. Hafezibakhtiari** - Dr. SH. Ashtari**
*- Assistant Professor of Periodontics Dept. - Faculty of Dentistry – Isfahan Islamic Azad University (Khorasgan).
 **- Dentist.
Background and Aim: Microbial plaque has been recognized as the main cause of periodontal diseases. The anatomy and morphology of the furcation area may favour plaque accumulation. The aim of this study was to evaluate the upper and lower first molars morphologically and anatomically.
 Materials and Methods: In this this descriptive study, 151 upper first molars and 222 lower first molars were randomly collected and measured regarding root trunk length, diameter of furcation entrance and degree of root concavity.
 Results: In lower molars, the averages of furcation entrance and root trunk diameter were more in buccal than lingual aspect (0.53 mm vs. 0.49 mm and 4.28 mm vs. 2.94 mm). The average concavity of mesial was more than distal root (0.98 mm vs. 0.54 mm) in lower molars. In upper molars, the average of distal furcal entrance was the most (0.72 mm) whereas the buccal furcal entrance diameter was the least (0.54 mm). In addition, the average root trunk was more in mesial (3.22 mm) than buccal (2.74 mm) and distal (2.93 mm) surfaces. The average concavity of mesial root was the most (0.25 mm) whereas palatal and distal roots had some degrees of concavity as 37.7% and 8%, respectively.
Conclusion: The furcation areas of the first molars, in most cases, can not be thoroughly cleaned with the blade of conventional curettes.
 Key words: First upper molar – First lower molar – Furcation – Furcal entrance – Root trunk – Root concavity.