Anatomy And Structure Of The Mandibular First Molar After Missing The Mandible CBCT Measurement Analysis And Comparative Analysis With The Contralateral

Objective:Mandibular first molar is clinically more planting denture teeth. In this study, unilateral mandibular first molars in patients with bilateral mandibular first molar region as control line CBCT scans and analysis, application software CBCT systems were measured inclination of the mandible and mandibular nerve canal position to observe the mandible shape, mental foramen position to know the area under the mandible, mandibular canal, mental foramen position on CBCT images displayed characteristics, comparing the above observations of the differences between the two sides, while the analysis of gender differences in the uninvolved. Provide a theoretical basis for the design of regional dental implant surgery. Methods:Select 2011.3-2013.12 in Luzhou Medical College Hospital of Stomatology repair outpatients and 136 tablets taken CBCT side 68 cases meet the standards of imaging data were analyzed retrospectively. Among women 28 cases (56 sides), male 40 cases (80 sides). Use Ondemand 3D software mandibular first molar area for data analysis. Inclination measurement and analysis of the mandible. (2) measurement and analysis of the position of the mandibular canal:2.1 mandibular canal mandibular lingual wall to lingual bone plate distance (ML); 2.2 mandibular canal from the mandibular buccal wall to the buccal bone plate (MB); 2.3 mandibular canal wall down to the lower edge of the mandible distance (MD).3 mandible morphology observed.4. Observe mental foramen position. The above observations comparing the differences between the two sides, and to make a comparative analysis of gender. All data were statistically analyzed using SPSS20.0 software deal. Inspection standards α= 0.05. Results:1 inclination of the mandible:ipsilateral mean 84.72 ° ± 3.50 °, contralateral mean 83.74 ° ± 3.59 °, ipsilateral greater than contralateral, the average difference between the two sides of the same patient 3.24 ° ± 0.83 °, differences there was statistically significant (P<0.05), total average on both sides of 82.99 ° ± 15.27°, no significant difference (P sex between> 0.05); 2 position of the mandibular nerve canal:2.1 lingual wall to the mandibular canal mandibular lingual plate distance (ML):ipsilateral ML mean 2.65 ± 0.86mm, contralateral ML mean 2.99 ± 0.96mm, affected less than the contralateral, the average difference between the two sides of the same patient was 0.84 ML ± 0.71mm, the difference was statistically significant (P<0.05), total average sides ML 2.82 ± 0.92mm; 2.2 mandibular canal from the mandibular buccal wall to the buccal bone plate (MB):ipsilateral MB average value of 5.74 ± 1.28mm, contralateral MB mean 5.77 ± 1.29mm, affected less than the contralateral, the average difference between the two sides of the same patient MB was 0.77 ± 0.33mm, the difference was statistically significant (P<0.05), two side MB total average 5.75 ± 1.10mm; 2.3 mandible mandibular canal under the lower edge of the wall to the distance (MD):MD ipsilateral mean 8.49 ± 1.61mm, MD contralateral mean 8.75 ± 1.65mm, affected less than the contralateral, the difference between both sides of the same patient MD the average value of 0.87 ± 0.59mm, the difference was statistically significant (P<0.05), total average on both sides of MD 8.48 ± 1.57mm; location 2.4 mandibular nerve canal in the mandibular first molar region partial lingual, buccal and lingual the ratio is about 2:1; 2.5 ML, MB, MD were not statistically different between the sexes (P> 0.05).3 Mandible Form: 3.1 A type (female buccal, lingual round):10 ipsilateral side (7.35%),22 contralateral side (16.18%); 3.2 B-type (round buccal, lingual female):16 ipsilateral side (11.76%),22 contralateral side (16.18%); 3.3 C type (buccal and lingual are rounded):42 ipsilateral side (30.88%),24 contralateral side (17.65%), mandible shape between the sexes and the sides were not statistically different (P> 0.05).4 chin hole locations:between 4.1 molar and second premolar first:10 side ipsilateral (7.35%),8 contralateral side (5.88%); between 4.2 and first premolar and second premolar:suffering side 12 side (8.82%),18 contralateral side (13.24%); 4.3 second premolar apical:46 ipsilateral side (33.82%),42 contralateral side (30.88%), mental foramen position in the ipsilateral no significant difference (P> 0.05) between the healthy side. Conclusion:1 ipsilateral mandibular inclination greater than the contralateral, suggesting edentulous bone resorption is greater than the buccal and lingual alveolar crest moved to the buccal. (2) the location of the mandibular nerve canal:ML value of 2.1 ipsilateral, MB value, MD values were less than the contralateral, suggesting the edentulous mandible buccal, lingual, both under mandibular bone resorption; 2.2 mandibular canal position in the mandibular first molar region partial lingual, buccal and lingual proportion of about 2:1, the area planted to avoid biased buccal inferior alveolar nerve can have some significance.3 mandible shape:32 Side A (23.53%), suggesting that the risks of dental implants buccal perforation; B-type 38 side (27.94%), suggesting that the risk of dental implants lingual perforation exists; C type 66 side (48.53%), the largest proportion, relatively little wear occurs side risk.4. Mental foramen position 18 between the first side and the second premolar teeth (13.24%), suggesting that when the mandibular first molar area planted soft tissue flap surgery, should be taken to avoid damage to the anatomy of the area.