Torii Kengo, Chiwata Ichiro
Torii dental clinic, 1-23-2 Ando, Aoi-ku, Shizuoka-shi, 420-0882, Japan.
J Med Case Rep. 2007 Sep 12;1:85. doi: 10.1186/1752-1947-1-85.
Although the discrepancy between the habitual occlusal position (HOP) and the flat bite plate-induced occlusal position (BPOP) (regarded as the muscular physiological reference position) has been recently reported to be related to symptoms of temporomandibular disorders (TMDs), it still remains unclear whether the occlusal equilibration in the reference position is effective to resolve TMD-related discrepancy and symptoms. Aural symptoms (otalgia, tinnitus, vertigo et cetera) have been included under TMD symptoms.
To examine the effect of occlusal equilibration for the treatment of TMDs, occlusal equilibration was performed for a patient with aural symptoms (otalgia, tinnitus and vertigo) of unknown etiology in the right ear. An occlusal analysis was performed on this patient with dental models mounted on an articulator after relieving painful symptoms by an appliance therapy and a discrepancy was identified (p < 0.005). Occlusal equilibration in the BPOP was then performed for the patient by selective tooth grinding, because it was estimated that the interocclusal space between upper and lower occlusal surfaces would be rectified by selective grinding.
At completion of treatment, the discrepancy was not significant (p > 0.25), and the patient's right condyle had shifted 2.8 mm posteromedially in the horizontal plane, and the left condyle had shifted 1.0 mm laterally in the voluntarily closed position from the previous HOP. The aural symptoms of the patient were resolved, and there has been no recurrence to date after a two-year follow-up period.
An occlusal analysis should be performed in patients exhibiting TMD symptoms to identify the presence or absence of any discrepancy between the HOP and the BPOP. If a discrepancy exists, occlusal equilibration should be attempted in the reference position.
尽管最近有报道称习惯性咬合位置（HOP）与平咬板诱导的咬合位置（BPOP，被视为肌肉生理参考位置）之间的差异与颞下颌关节紊乱病（TMD）的症状有关，但参考位置的咬合平衡是否能有效解决与TMD相关的差异和症状仍不清楚。耳部症状（耳痛、耳鸣、眩晕等）已被纳入TMD症状之中。
为了研究咬合平衡对TMD治疗的效果，对一名右耳病因不明的耳部症状（耳痛、耳鸣和眩晕）患者进行了咬合平衡治疗。在通过矫治器治疗缓解疼痛症状后，用安装在牙合架上的牙模对该患者进行了咬合分析，并发现了差异（p < 0.005）。然后通过选择性调磨对该患者进行BPOP位置的咬合平衡，因为预计通过选择性调磨可纠正上下咬合面之间的牙合间隙。
治疗结束时，差异不显著（p > 0.25），患者的右髁突在水平面内向后内侧移动了2.8 mm，左髁突在自愿闭口位相对于先前的HOP向外移动了1.0 mm。患者的耳部症状得到缓解，经过两年的随访期，至今未复发。
对出现TMD症状的患者应进行咬合分析，以确定HOP与BPOP之间是否存在差异。如果存在差异，应尝试在参考位置进行咬合平衡。
