华中科技大学学报（医学版）
華中科技大學學報（醫學版）
화중과기대학학보（의학판）
Acta Medicinae Universitatis Scientiae et Technologiae Huazhong
2015年
5期
586-590
,共5页
根尖片%分角线投照%锥形束CT
根尖片%分角線投照%錐形束CT
근첨편%분각선투조%추형속CT
periapical film%bisecting angle technique%cone beam computed tomography(CBCT)
目的：探讨分角线法拍摄上颌第一磨牙根尖片的适宜角度。方法选取198例患者锥形束C T （CBC T ）资料，测量左、右两侧上颌第一磨牙近中舌尖之间距离、腭顶至上颌牙合平面高度、双侧上颌前磨牙和磨牙连线与左右第一磨牙连线所成角度（记其余角为角1）。记颧骨或颧弓最下缘为点a ，腭顶为点b ，腭根根尖为点c。分别测量点a、b连线与水平面所成夹角（角2）、点a、c连线与水平面所成夹角（角3）以及点b、c连线与水平面所成夹角（角4）。结果左、右两侧上颌第一磨牙近中舌尖之间距离均值为（40.48±2.05）mm ；腭顶至上颌牙合平面高度均值为（20.28±2.12）mm ；角1、2、3、4的均值分别为（15.83±4.95）°、（11.75±3.71）°、（21.66±6.22）°和（－2.62±7.17）°。各测量指标均值在男女性别分组及年龄分组中差异均无统计学意义。结论拍摄上颌第一磨牙根尖片时，X线管的最适宜水平角度是16°左右；最适宜垂直角度范围是－3°～22°左右，理论最佳投照角度为22.5°，与国内口腔放射影像学教科书中推荐值（30°）有偏差。
目的：探討分角線法拍攝上頜第一磨牙根尖片的適宜角度。方法選取198例患者錐形束C T （CBC T ）資料，測量左、右兩側上頜第一磨牙近中舌尖之間距離、腭頂至上頜牙閤平麵高度、雙側上頜前磨牙和磨牙連線與左右第一磨牙連線所成角度（記其餘角為角1）。記顴骨或顴弓最下緣為點a ，腭頂為點b ，腭根根尖為點c。分彆測量點a、b連線與水平麵所成夾角（角2）、點a、c連線與水平麵所成夾角（角3）以及點b、c連線與水平麵所成夾角（角4）。結果左、右兩側上頜第一磨牙近中舌尖之間距離均值為（40.48±2.05）mm ；腭頂至上頜牙閤平麵高度均值為（20.28±2.12）mm ；角1、2、3、4的均值分彆為（15.83±4.95）°、（11.75±3.71）°、（21.66±6.22）°和（－2.62±7.17）°。各測量指標均值在男女性彆分組及年齡分組中差異均無統計學意義。結論拍攝上頜第一磨牙根尖片時，X線管的最適宜水平角度是16°左右；最適宜垂直角度範圍是－3°～22°左右，理論最佳投照角度為22.5°，與國內口腔放射影像學教科書中推薦值（30°）有偏差。
목적：탐토분각선법박섭상합제일마아근첨편적괄의각도。방법선취198례환자추형속C T （CBC T ）자료，측량좌、우량측상합제일마아근중설첨지간거리、악정지상합아합평면고도、쌍측상합전마아화마아련선여좌우제일마아련선소성각도（기기여각위각1）。기권골혹권궁최하연위점a ，악정위점b ，악근근첨위점c。분별측량점a、b련선여수평면소성협각（각2）、점a、c련선여수평면소성협각（각3）이급점b、c련선여수평면소성협각（각4）。결과좌、우량측상합제일마아근중설첨지간거리균치위（40.48±2.05）mm ；악정지상합아합평면고도균치위（20.28±2.12）mm ；각1、2、3、4적균치분별위（15.83±4.95）°、（11.75±3.71）°、（21.66±6.22）°화（－2.62±7.17）°。각측량지표균치재남녀성별분조급년령분조중차이균무통계학의의。결론박섭상합제일마아근첨편시，X선관적최괄의수평각도시16°좌우；최괄의수직각도범위시－3°～22°좌우，이론최가투조각도위22.5°，여국내구강방사영상학교과서중추천치（30°）유편차。
Objective To examine the optimal angulation for a periapical radiograph of the maxillary first molar by using bi‐secting angle technique.Methods Cone beam computed tomography (CBCT )data of 198 patients were retrospectively ana‐lyzed.The following variables were measured ,including the distance between the mesial lingual cusp of the maxillary first mo‐lars ,the height of the palatine crest to the upper jaw plane ,the angle between the line of the maxillary premolars to molars and the line across the bilateral first molars(angle 1) ,the angle between the horizontal plane and the line across the lowest edge of zygoma or zygomatic arch and the top of palatine crest(angle 2) ,the angle between the horizontal plane and the line across the lowest edge of zygoma or zygomatic arch to the palatal root apices of the maxillary first molar(angle 3)and the angle between the horizontal plane and the line across the top of palatine crest and the palatal root apices of the maxillary first molar(angle 4) . Results The average distance of the mesial lingual cusp of the maxillary first molars was(40.48 ± 2.05)mm.The average height of the palatine crest to the upper jaw plane was(20.28 ± 2.12)mm.The average value of angles 1 to 4 was(15.83 ± 4.95)° ,(11.75 ± 3.71)° ,(21.66 ± 6.22)° and(-2.62 ± 7.17)° ,respectively.There was no significant difference in these varia‐bles between different sex and age groups.Conclusion The appropriate horizontal angle for X‐ray tube is about 16° in taking a maxillary molar periapical radiograph.The appropriate vertical angles are between-3° and 22°.The optimal imaging angulation is theoretically 22.5°.These findings are not in accordance with the data recommended by the textbook.
