بررسی استاندارهای سفالومتریک دانش آموزان پسر دارای اکلوژن نرمال در همدان

The important base of orthodontic treatment is correct diagnosis . One of the&nbsp;diagnostic tools is lateral cephalogram. There are some differences in normal&nbsp;standards between different races. The&nbsp;present&nbsp;study&nbsp;was&nbsp;carried out with&nbsp;the&nbsp;aim&nbsp;of determining&nbsp;and&nbsp;assessing&nbsp;the&nbsp;cephalometric standards of boys with the&nbsp;age of 17 to 20&nbsp;years old in Hamadan. Among 1204 boys of preuniversity centers ,&nbsp;27 persons&nbsp;were&nbsp;selected&nbsp;based&nbsp;on IOTN and normal&nbsp;occlusal standards. Lateral cephalograms were obtained in&nbsp; Natural Head Position. 22 cephalometric&nbsp;variables (15 angles , 5 lines , 2 ratios ) &nbsp;&nbsp; were determined and measured three times by an orthodontist . Student t - test&nbsp;used for analysis. Mean age of the cases were 18.2&plusmn;1.4 years. Range of reliability coefficient&nbsp;was between 0.901 to 0.986. In comparison with similar studies following variables&nbsp;were statistically different at p<0.05 level: Articular &nbsp;Angle= 146 ,Gonial Angle =118 ,&nbsp;NPog-TH =89 , AB-TH = 4.6 , L1 &ndash;TH =116 , Go Gn &ndash;TH =20 , Ant. Cranial se =76mm. The length of anterior cranial base in our study&nbsp;was significantly less than&nbsp;Michigan standards and there was a tendency to more traight&nbsp;profile&nbsp;in this&nbsp;evaluation . In&nbsp;comparison&nbsp;with the Cooke standards there&nbsp;was&nbsp;less &nbsp;protrusion in&nbsp;mandibular&nbsp;incisors and&nbsp;more counter-clockwise&nbsp;rotation of&nbsp;mandible. In&nbsp;comparison with similar study on girls(with normal occlusion and 18.2&plusmn;1.1 years old) &nbsp;&nbsp; linear measurements were generally greater in boys. Therefore it&nbsp;is&nbsp;important&nbsp;to&nbsp;consider&nbsp;the&nbsp;ethnic and&nbsp;racial&nbsp;variations&nbsp;in our&nbsp;ideal&nbsp;treatment plan.