제3대구치와 하악관과의 위치 관계에서 치과용 Cone beam CT의 유용성 = POSITIONAL RELATIONSHIP OF THE MANDIBULAR CANAL AND IMPACTED THIRD MOLARS BY USING DENTAL CONE BEAM COMPUTED TOMOGRAPHY

다국어 초록 (Multilingual Abstract)

We sought to evaluate the relationship between the mandibular canal and impacted mandibular third molars by using dental cone beam computed tomograph(CBCT) for third molar surgery. A total of 111 patients(177 teeth) offered the images through CBCT and panoramic radiography for the extraction of the mandibular third molars. In CBCT, the accurate relationship between the third molar and the mandibular canal were evaluated. In panoramic radiographies, we evaluated the impacted level and superimposition sign of the mandibular third molar with the mandibular canal, and also, the radiopacity of the white line in the canal. Data were statistically analyzed and estimated by $X^2$-test. In CBCT finding, high prevalence of contact between the mandibular canal and roots occured in the deep impacted third molars, narrowing mandibular canals, bending mandibular canals and cases where the radiopacity of white line of canals were "absence" on panoramic images. It showed statistical significance (P<0.05). When evaluating the mandibular canal and the roots through the panoramic radiography for third molar extraction, it could be difficult to diagnosis accurately. Thus, it is required to have an accurate diagnostic approach through CBCT that could evaluated the location between mandibular canal and root.

참고문헌 (Reference)

1 Vanier MW, "Three-dimensional dental imaging by spiral CT" 84 : 561-, 1997

2 Enciso R, "Thirdmolar impaction diagnostic with cone-beam computerized tomography" 1281 : 1996-, 2005

3 Nakagawa Y, "Third molar position: Reliability of Panoramic Radiography" 65 : 1303-, 2007

4 Rood JP, "The radiological prediction of inferior alveolar nerve injury during third molar surgery" 28 : 20-, 1990

5 Garmon WB, "The accuracy of dental panoramic tomographs in determining the root morphology of mandibular third molar teeth before surgery" 95 : 119-, 2003

6 Rud J, "The Split bone technic for removal of impacted mandibular third molars" 28 : 416-, 1970

7 Bataineh AB, "Sensory nerve impairment following mandibular third molar surgery" 59 : 1012-, 2001

8 Howe GL, "Prevention of damage to the inferior dental nerve during the extraction of mandibular third molar" 109 : 355-, 1960

9 Maegawa H, "Preoperative assessment of the relationship between the mandibular third molar and the mandibular canal by axial computed tomography with coronal and sagittal reconstruction" 96 : 639-, 2003

10 Nakagawa Y, "Preoperative application of limited cone beam computerized tomography as an assessment tool before minor oral surgery" 31 : 322-, 2002

11 Behbehani F, "Prediction of mandibular third-molar impaction in adolescent orthodontic patients" 130 : 47-, 2006

12 Hattab FN, "Positional changes and eruption of impacted mandibular third molars in young adults. A radiographic 4-year follow-up study" 846 : 604-, 1997

13 Gahleitner A, "Lingual vascular canals of the mandible; Evaluation with dental CT" 220 : 186-, 2001

14 Valmaseda-Castellin E, "Inferior alveolar nerve damage after lower third molar surgical extraction ; A prospective study of 1117 surgical extractions" 92 : 377-, 2001

15 Carmichael FA, "Incidence of nerve damage following third molar removal ; A West of Scotland Oral Surgery Research Group Study" 30 : 78-, 1992

16 Arai Y, "Development of a compact computed tomographic apparatus for dental use" 28 : 245-, 1999

17 Kaeppler G, "Conventional cross-sectional tomographic evaluation of mandibular third mo" 31 : 49-, 2000

18 Danforth RA, "Cone beam volume tomography: an imaging option for diagnosis of complex mandibular third molar anatomical relationships" 31 : 847-, 2003

19 Venta I, "Assessing the eruption of lower third molars on the basis of radiographic features" 29 (29): 259-, 1991

20 Chandler LP, "Accuracy of radiographs in classification of impacted third molar teeth" 46 : 656-, 1988

21 Pawelzik J, "A comparison of conventional panoramic radiographs with volumetric computed tomography images in the preoperative assessment of impacted mandibular third molar" 60 : 979-, 2002