Khullar S M, Emami B, Westermark A, Haanaes H R
Department of Oral Surgery and Oral Medicine, University of Oslo, Norway.
Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 1996 Aug;82(2):132-8. doi: 10.1016/s1079-2104(96)80215-0.
Low-level laser treatment has been advocated as a possible treatment for patients with paresthesia. An objectively verified improvement in sensory function is relevant if, at the same time, it is perceived as a subjective improvement by the patient. The aim of this double blind clinical study was to see if low-level laser treatment with a GaAlAs laser (820 nm, Rønvig, Denmark) resulted in objectively verified improvement in sensory function and whether this correlated with the patient's subjective evaluation subsequent to treatment.
The 13 patients in this study had all undergone saggittal split ramus osteotomy resulting in either compression or traction of the inferior alveolar nerve as reported by the surgery notes. The material was collected from a consecutive series of patients at the Karolinska Hospital, all of whom had shown reduced sensibility at their final 2-year postoperative checkup. The patients were randomly divided into two groups; one (eight subjects) group received real low-level laser treatment (4 x 6 J per treatment along the distribution of the inferior alveolar nerve, at the following points extraoral: lateral third of lower lip, intraoral; buccally to the apex of the second premolar tooth and the apex of the second molar tooth; lingually in the region of the mandibular foramen; for a total of 20 treatments). The other group received an equivalent placebo treatment. The study was conducted in a double blind fashion for both patient and doctor as the low-level laser equipment had two settings, A and B, one of which was an unknown void setting. The degree of mechanoceptor neurosensory deficit was assessed by Semmes Weinstein monofilaments (North Coast Medical, USA) and the degree of thermoceptor neurosensory deficit was assessed by a Thermotester (Somedic, Sweden). The degree of subjective neurosensory deficit was assessed by means of a visual analogue scale. Both variables and the degree of subjective injury were comparable between the two groups before starting treatment.
The patients in the real low-level laser treatment group experienced a subjective improvement in both lip (p = 0.01) and chin (p = 0.02) after completion of the course of treatment. In addition, this group showed a significant decrease in the area of mechanoperception neurosensory deficit (p = 0.01) compared with no difference in the placebo group. The real low-level laser treatment group exhibited a strong tendency toward improvement in mechanoreceptor neurosensory deficit in the areas of most damage for both lip and chin. This improvement was especially pronounced in the lip region (p = 0.06). No similar tendency was demonstrated in the placebo group. Neither group showed any significant change or tendency to improvement in thermoception on completion of the course of treatment.
In conclusion GaAlAs low-level laser treatment results in both a subjective and objective improvement in mechanical sensory perception in long-standing neurosensory deficit in the inferior alveolar nerve.
低强度激光治疗已被提倡作为一种可能治疗感觉异常患者的方法。如果同时患者主观感觉也有所改善，那么感觉功能在客观上得到证实的改善才具有意义。本双盲临床研究的目的是观察使用砷化镓铝激光（820纳米，丹麦伦维格）进行低强度激光治疗是否能在客观上证实感觉功能有所改善，以及这是否与治疗后患者的主观评估相关。
本研究中的13名患者均接受了矢状劈开下颌升支截骨术，手术记录显示下牙槽神经受到了压迫或牵拉。研究材料取自卡罗林斯卡医院连续的一系列患者，所有患者在术后2年的最终检查中均显示感觉减退。患者被随机分为两组；一组（8名受试者）接受真正的低强度激光治疗（沿着下牙槽神经分布区域每次治疗4×6焦耳，在以下口外部位：下唇外侧三分之一处、口内；第二前磨牙根尖颊侧和第二磨牙根尖颊侧；下颌孔区域舌侧；共治疗20次）。另一组接受等效的安慰剂治疗。由于低强度激光设备有A和B两种设置，其中一种是未知的无效设置，因此该研究对患者和医生均采用双盲方式进行。通过Semmes Weinstein单丝（美国北海岸医疗公司）评估机械感受器神经感觉缺陷程度，通过热敏测试仪（瑞典Somedic公司）评估温度感受器神经感觉缺陷程度。通过视觉模拟量表评估主观神经感觉缺陷程度。在开始治疗前，两组的这两个变量以及主观损伤程度具有可比性。
真正的低强度激光治疗组患者在完成治疗疗程后，嘴唇（p = 0.01）和下巴（p = 0.02）的主观感觉均有改善。此外，与安慰剂组无差异相比，该组机械感觉神经感觉缺陷区域显著减小（p = 0.01）。真正的低强度激光治疗组在嘴唇和下巴损伤最严重的区域，机械感受器神经感觉缺陷有明显的改善趋势。这种改善在嘴唇区域尤为明显（p = 0.06）。安慰剂组未显示出类似趋势。在完成治疗疗程后，两组在温度感觉方面均未显示出任何显著变化或改善趋势。
总之，对于下牙槽神经长期存在的神经感觉缺陷，砷化镓铝低强度激光治疗在机械感觉方面能带来主观和客观的改善。
