應用錐束電腦斷層掃描（CBCT）比較台灣和美國成年人齒槽骨骨質密度,各種解剖標誌 與骨硬化病變評估研究

Comparative Study of the Alveolar Bone Density, Various Anatomic Landmarks and Osteosclerosis of the jaws between Taiwanese and American Cohorts Using Cone Beam Computed Tomography

陳佳惠(Chia-Hui Chen)

指導教授 ： 陳玉昆

高雄醫學大學/口腔醫學院/牙醫學研究所/博士(2013年)

https://doi.org/10.6832/KMU.2013.00132

摘要

研究目的
錐束電腦斷層掃描 (CBCT) 於口腔內與口腔外的應用，具有非常良好的幾何準確度與影像重組多度空間方向的優點。本研究的目標是應用CBCT影像比較台灣與美國族群，進行以下測量: 1) 測量齒槽骨骨質以預測植牙位置穩定度事前評估; 2) 盡可能得到頦孔 (mental foramen) 與其前環 (anterior loop) 結構的資訊以降低植牙手術傷害到神經的危險性; 3) 調查這二個族群中顎骨骨硬化病變 (osteosclerosis) 其盛行率、分布及放射線特徵。
材料與方法
CBCT影像設備為I-CATR Cone Beam 3-D Dental Imaging System牙科成像系統，重組多切面和三維空間影像以供二群體進行測量。
結果
1）比較美國與台灣族群的平均鬆質骨密度，除了上顎骨之小臼齒區無顯著性差異之外，其餘所有測量位置皆有顯著性差異；2) 於測量頦孔 (mental foramen) 至下頜邊界高度，臺灣 (10.13 ± 1.66毫米) 與美國 (9.84 ± 2.01毫米) 族群統計上無統計學差異 (P = 0.2681)；於測量頦孔直徑，臺灣(2.13 ± 0.47毫米) 與美國 (2.26 ± 0.67毫米) 族群統計上也無統計學差異 (P = 0.1161)；不過, 前環的平均長度臺灣族群 (7.61 ± 1.81毫米)顯著長於美國族群 (6.22 ± 1.68毫米) (P < 0.0001)；3) 比較台灣與美國族群顎骨骨硬化病變其盛行率有顯著性差異, 且骨硬化體積,舌-頰側距離與近-遠心距離測量值亦有顯著性差異; 於性別方面, 台灣或美國族群其男性與女性並無顯著性差異；台灣族群大部分有顎骨骨硬化病變發現於40–49歲年齡層 (38%) 而美國族群則在30–39歲與60歲以上年齡層 (36%)。
討論與總結
我們的研究表明：1）鬆質骨密度是會依據齒槽骨位置、種族和性別而有所差異; 2）美國人的頦孔位置比台灣人更接近於下顎骨的下緣; 3）美國人頦孔的直徑比臺灣人大; 4）台灣人前環長度則比美國人長; 5）台灣與美國族群間顎骨骨硬化病變之盛行率有顯著性差異。以上這些差異可能是由於種族的影響，本研究所得之資訊具有潛在價值的臨床意義。

關鍵字

錐束電腦斷層掃描 ； 骨質密度 ； 頦孔 ； 前環 ； 骨硬化病變

並列摘要

Purposes
Cone beam computerized tomography (CBCT) can provide a good geometric accuracy and spatial orientations of the reconstructed images for various dental practices. The current study aimed to compare: 1) the alveolar bone density of jawbones; 2) the location and diameter of the inferior alveolar canal at the mental foramen and length of the anterior loop; 3) the frequency and radiographic features of osteosclerosis of the jaws, between Taiwanese and American cohorts using CBCT.
Materials and Methods
CBCT imaging was performed with an I-CATR Cone Beam 3-D Dental Imaging System and reconstructed into multiple-plane views to evaluate the alveolar bone density of jawbones; location and diameter of the inferior alveolar canal at the mental foramen and length of the anterior loop; frequency, distribution, and radiographic features of osteosclerosis of the jaws, between Taiwanese and American cohorts.
Results
1) There were significant differences in the mean cancellous bone density for all sites of jawbones, with the exception of in the maxilla premolar region between American and Taiwanese cohorts.
2) There was no statistically significant difference (P = 0.2681) in the distance from the mental foramen to the inferior border of the mandible (mandibular border height) between American (9.84 ± 2.01 mm) and Taiwanese (10.13 ± 1.66 mm) cohorts. No significant difference was found (P = 0.1161) in the inferior alveolar canal diameter between these two cohorts (2.26 ± 0.67 mm & 2.13 ± 0.47 mm, respectively). The anterior loop length of Taiwanese (7.61 ± 1.81 mm) was significantly longer than that of Americans (6.22 ± 1.68 mm) (P < 0.0001).
3) There was a significant difference in the frequency of osteosclerosis between the Taiwanese and American cohorts. There were significant differences between the Taiwanese and American cohorts in the measurements of volume, buccal-lingual distance, and mesial-distal distance. No significant differences between males and females were found in either cohort. Most osteosclerotic lesions (38%) in the Taiwanese cohort were found in the age range of 40–49 years, while most lesions (36%) in the American cohort were found in the age ranges of 30–39 years and ?d 60 years.
Discussion & Conclusion
Our study indicated that: 1) cancellous bone density is associated with alveolar bone site, ethnicity, and gender; 2) the location of mental foramen of Americans was closer to the inferior border of the mandible than Taiwanese; 3) the diameter of the inferior alveolar canal of Americans was larger than Taiwanese; 4) the anterior loop of Taiwanese was longer than Americans; and 5) There was a significant difference in the frequency of osteosclerosis between Taiwanese and American cohorts. These differences may be due to the racial influence and this information may possess potential valuable clinical relevance.

並列關鍵字

CBCT ； Bone Density ； Mental foramen ； Anterior loop ； Osteosclerosis

參考文獻

1. Mozzo, P., et al., A new volumetric CT machine for dental imaging based on the cone-beam technique: preliminary results. European Radiology, 1998. 8(9): p. 1558-1564.

2. Gupta, R., et al., Experimental flat-panel high-spatial-resolution volume CT of the temporal bone. American Journal of Neuroradiology, 2004. 25(8): p. 1417-1424.

3. Ludlow, J.B., et al., Accuracy of measurements of mandibular anatomy in cone beam computed tomography images. Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontology, 2007. 103(4): p. 534-542.

4. Kim, T.S., et al., A Comparison of cone-beam computed tomography and direct measurement in the examination of the mandibular canal and adjacent structures. Journal of Endodontics, 2010. 36(7): p. 1191-1194.

5. Hashimoto, K., et al., Comparison of image performance between cone-beam computed tomography for dental use and four-row multidetector helical CT. Journal of Oral Science, 2006. 48(1): p. 27-34.