文獻回顧：正顎手術後的咬力及張口量的變化

Bite Force and Maximum Mouth Opening after Orthognathic Surgery

為了要同時達到顏面美觀、良好功能咬合、組織的健康與結果的穩定度，正顎手術在矯正治療中是有其必要性。在建議病人做正顎手術的同時，應告知病人正顎手術有其優點、術後的可能副作用、和生理上的暫時性影響，讓患者在手術前能更清楚即將面臨的變化與影響，使其能更安心地面對手術以及術後恢復期間的過渡性變化。下顎骨的功能可以藉由最大張口度、咬力及肌肉耐久性來做評估。正顎手術術後常見的術後生理上的暫時性影響是下顎運動受到限制（hypomobility），本篇回顧主要整理與比較正顎手術後評估最大張口度、咬力等相關下顎骨功能的文獻報告。根據相關文獻回顧的結果顯示，將骨性第二級異常咬合的病人組別與骨性第三級異常咬合的病人組別相比，前者其術後張口度變小1-2。顎間固定的時間愈長，張口度的恢復愈慢3 。關於正顎手術術式與咬力的關係方面，咬力及咬合接觸變化呈現正相關性，術後大約六個月到一年咬力可達術前的量，正顎手術的不同術式並不會顯著影響咬力。

In order to achieve better facial esthetics, functional occlusion, maintaining tissue health and stable treatment results, orthognathic surgery is required in certain orthodontic patients. While planning orthognathic surgery, we should inform patients benefits and risks associated in this treatment modality. Possible side effects including the post-operational temporary physiological influences to the patient should be mentioned.Thus, patients will be less anxious and deal with those problems more comfortably. The most common post-operation influences of orthognathic surgery is hypomobility. The objective measurements for mandibular function are maximum mouth opening (MMO), maximum bite force, and muscle fatigability. We summarize and compare the literatures regarding changes of mandibular function before and after orthognathic surgery. MMO after orthognathic surgery of Class II malocclusion patients was significantly smaller than that of Class III malocclusion patients. The longer the duration of maxillomandibular fixation, the slower the recovery of the MMO. Bite force was positively correlated with occlusal contact and recovered fully 6 months after surgery. The types of orthognathic surgery did not affect bite force significantly.