ความกว้างของทางเข้าช่องรากฟัน และความยาวลำตัวรากฟันของฟันกรามแท้ซี่ที่ 1 และฟันกรามแท้ซี่ที่ 2 ของประชากรที่อยู่ในประเทศไทยวัดโดยระบบวิเคราะห์ภาพด้วยคอมพิวเตอร์ / สุพัตรา แสงอินทร์ = The furcation entrance width and root trunk length in Thai first and second permanent molars measured by a computer-assisted image analysis system / Supatra Sang-in
The anatomy of molar roots and their furcation region influences both pathogenesis of periodontal destruction and therapeutic attempts. The main objective of the present study was to investigate the furcation entrance width and root trunk length in Thai first and second permanent molars. The study samples consisted of 200 maxillary molars and 200 mandibular molars (100 first and 100 second molars). The furcation entrance width and root trunk length were measured by a computer-assisted image analysis system, and the difference between those of first and second molars was examined using Z-test. In maxillary first molars, the mean values of buccal, mesial and distal root trunk lengths were 4.27 ± 0.85, 4.23 ± 0.81 and 4.60 ± 0.93 mm, while those of maxillary second molars were 4.22 ± 0.77, 4.47 ± 0.73 and 4.52 ± 0.85 mm. respectively. Also, the mean values of buccal and lingual root trunk lengths in mandibular first molars were 3.22 ± 0.62 and 4.25 ± 0.62 mm, while those of mandibular second molars were 3.35 ± 0.68 and 4.30 ± 0.67 mm. The mean values of buccal, mesial and distal furcation entrance widths in maxillary first molars were 0.78 ± 0.32, 1.15 ± 0.39, and 1.02 ± 0.43 mm, while those of maxillary second molars were 0.74 ± 0.27, 1.13 0.38 and 1.02 ± 0.33 mm respectively. Also, the mean values of buccal and lingual furcation entrance widths in mandibular first molars were 1.11 ± 0.31 and 1.33 ± 0.37 mm, while those of mandibular second molars were 0.84 ± 0.29 and 0.96 ± 0.37 mm. The comparisons may be summarized as follows. The mesial root trunk length of maxillary second molars was significantly longer than that of the maxillary first molars (p<0.05). The buccal root trunk length of mandibular molars was significantly shorter than that of the ligual (p<0.05). For the furcation entrance width, the mesial furcation entrance of maxillary molars appeared to be wider when compared with the distal and buccal furcation entrances: and in mandibular molars, the buccal furcation entrance was apparently narrower compared to the lingual one (p<0.05). Also, the furcation entrance widths of mandibular first molars were significantly greater than those of mandibular second molars (p<0.05).
