Čimić Samir, Žaja Matea, Kraljević Sonja, Šimunković Marijan, Kopić Amir
University of Zagreb School of Dental Medicine.
Acta Stomatol Croat. 2016 Jun;50(2):116-121. doi: 10.1564/asc50/2/3.
The aim of this study was to determine the effect of occlusal interferences on the position of condyles.
The study included 10 participants. All recordings of the condylar position were done using ultrasound jaw tracking device with six degrees of freedom. Paraocclusal tray was fixed in the lower jaw, and the artificial occlusal interference was made on the lower left second premolar with a composite resin, thickness of 1 mm. Condylar shift at the position of the occlusion with the artificial occlusal interference was measured using a jaw tracking device. Condylar positions were determined based on the Cartesian coordinate system. All deviations were measured according to a reference position which was the position of maximum intercuspation. Linear values of deviations between the reference position and the position of the occlusion with the occlusal interference were determined from the values of the Cartesian coordinate system.
Average superior condylar shift was 0.17 mm, SD 0.39. Average linear deviation between the position of maximum intercuspation and the position of the occlusion with the occlusal interference was 0.48 mm (SD 0.29, min 0.17 mm, max 1.19 mm).
Occlusal interference leads to immediate change of the condylar position within the temporomandibular joint. Average values of determined superior condylar position confirm occurrence of lever within dental arches. The obtained results must be interpreted within the limitations of this study (immediate measurement of the condylar position). Further research is needed for the analysis of progression of the condylar position with occlusal interferences.
本研究旨在确定咬合干扰对髁突位置的影响。
该研究纳入了10名参与者。所有髁突位置的记录均使用具有六个自由度的超声下颌追踪装置完成。将副咬合托盘固定在下颌,并用厚度为1mm的复合树脂在下颌左侧第二前磨牙上制造人工咬合干扰。使用下颌追踪装置测量存在人工咬合干扰时咬合位置的髁突移位。髁突位置基于笛卡尔坐标系确定。所有偏差均根据作为最大牙尖交错位的参考位置进行测量。参考位置与存在咬合干扰时的咬合位置之间偏差的线性值由笛卡尔坐标系的值确定。
髁突平均向上移位0.17mm,标准差为0.39。最大牙尖交错位与存在咬合干扰时的咬合位置之间的平均线性偏差为0.48mm(标准差0.29,最小值0.17mm,最大值1.19mm)。
咬合干扰会导致颞下颌关节内髁突位置立即改变。所确定的髁突向上位置的平均值证实了牙弓内杠杆作用的发生。所得结果必须在本研究的局限性(髁突位置的即时测量)范围内进行解释。需要进一步研究以分析咬合干扰时髁突位置的进展情况。