低能量雷射對臨床矯正治療的影響

Abstract

矯正治療花費的時間及過程中牙齒移動的疼痛為臨床上病人最常見的顧慮， 近年來隨低能量雷射在醫療領域的應用漸廣，在矯正治療相關的應用亦被提及， 然而至今相關臨床試驗數量甚少，且實驗設計變異性大，其效果至今未有定論。 本臨床試驗目的為探討低能量雷射在矯正治療上的應用，包括牙齒移動速率及疼 痛控制的效果。所使用之雷射為波長 980 nm 之二極體雷射，輸出功率為 50 mW continuous wave，單點能量密度 10.4 J/cm2。在牙齒移動速率實驗中在上顎對稱拔 除第一小臼齒後、以犬齒後退作為觀察對象，最終參與的受試者有三位。實驗採 single blind、split mouth design。受試者需在除例行矯正回診外，每週回診於實驗 側犬齒頰側及腭側進行照射，單顆牙齒所受到的總照射能量為 10 J，同時每月進 行口內掃描以紀錄每月牙齒移動距離。本實驗結果顯示在首一個月時雷射側移動 速率為 0.39±0.28 mm/month，較控制側 0.23±0.08 mm/month 高。而最終整體平均 速率則差異不大(分別為 0.51±0.17 mm/month and 0.50±0.06 mm/month)。但因樣 本數不足無法進行統計分析。 疼痛控制部分則以橡皮隔離圈放置作為觀察目標，納入上顎或下顎齒列完整 且左右對稱、並需在第一大臼齒近遠心放置橡皮隔離圈者。在放置隔離圈當下於 第一大臼齒頰舌側進行單一次雷射照射，單顆牙齒所受到的總照射能量為 10 J。 以 NRS 量表請病人返家後自行填寫，記錄放置後七天內的疼痛分數。最終回收 之有效問卷共 38 份，包括上顎 19 份、下顎 19 份。結果顯示下顎疼痛分數較上 顎高(累積疼痛平均分別為 37.37±18.84 及 24.16±18.75 分)。本實驗亦觀察到雷 射照射之影響在上下顎似乎呈現不同趨勢，上顎雷射側的疼痛分數略高於對照 側，但下顎雷射側之疼痛分數則較低。然而，不論是最大疼痛值或是隔離橡皮圈 置放期間累積之疼痛數值，雷射側與對照側間均未觀察到統計上顯著差異。

Orthodontic treatment, a time consuming process, along with the related pain sensation during tooth movement are the two major concerns for patients to receive the treatment. Low level laser therapy (LLLT) has now been applied widely in medical use, including orthodontics. However, the effectiveness of LLLT remained controversial since relative few clinical trials has been published and the wide variations among the studies. In this clinical trial, we test the effectiveness of LLLT in orthodontics, including tooth movement rate and pain control. The laser applied in this clinical trial was 980 nm diode laser, with output power of 50 mW in a continuous wave. The energy density was 10.4 J/cm2. For evaluating canine retraction rate, patients with upper bilateral first premolar extractions were included with a single-blind-split-mouth design. The laser was irradiated on the experimental canine buccally and palatally, with the total energy 10 J/tooth, once a week until the extraction space was closed on either side. Intraoral scanning was performed monthly to record tooth movement. Three subjects were recruited and completed the trial. The retraction rate in the first month was 0.44±0.14 and 0.29±0.05 mm/month at laser and placebo sides respectively. The overall rate was 0.50±0.25 and 0.45±0.09 mm/month at laser and placebo sides respectively. The statistical comparison was unavailable due to limited sample size. The discomfort induced by separator insertion was used to study pain with a split mouth design. The separators were placed mesially and distally to the first molar, followed by single dose LLLT application, 10 J per tooth. The patients were asked to fill the NRS pain score chart in the following 7 days. Total of 38 charts were collected in the end, including 19 upper jaws and 19 lower jaws. It revealed that the accumulated pain was higher in lower jaws (37.37±18.84 and 24.16±18.75 respectively). Different trend between upper and lower jaws was observed. The pain score of LLLT side was higher than placebo side in maxilla, but was lower in mandible. However, neither the maximal pain intensity nor accumulated pain showed significant differences between LLLT and placebo sides.