Dagsdóttir L K, Bellan V, Skyt I, Vase L, Baad-Hansen L, Castrillon E, Svensson P
Section of Orofacial Pain and Jaw Function, Department of Odontology and Oral Health, Aarhus University, Aarhus, Denmark.
Scandinavian Center of Orofacial Neurosciences (SCON), Aarhus, Denmark.
J Oral Rehabil. 2018 Jan;45(1):1-8. doi: 10.1111/joor.12581. Epub 2017 Nov 18.
Chronic oro-facial pain patients often perceive the painful face area as "swollen" without clinical signs, that is a perceptual distortion (PD). Local anaesthetic (LA) injections in healthy participants are also associated with PD.
The aim was to explore whether PD evoked by LA into the infraorbital region could be modulated by adding mechanical stimulation (MS) to the affected area.
Mechanical stimulation was given with a brush and a 128-mN von Frey filament. Firstly, sixty healthy participants were randomly divided into three groups: (i) LA control, (ii) LA with MS, (iii) isotonic solution (ISO) with MS as an additional control condition. To further examine the role of a multisensory modulation, an additional experiment was conducted. Twenty participants received LA with MS (filament) in addition to visual feedback of their distorted face. The results of the two experiments are presented together.
All three LA groups experienced PD; per contra, PD was not reported in the ISO group. MS alone did not change the magnitude of PD: brush (P = .089), filament (P = .203). However, when the filament stimulation was combined with additional visual information of a distorted face, there was observable decrease in PD (P = .002).
The findings indicate the importance of multisensory integration for PD and represent a significant step forward in the understanding of the factors that may influence this common condition. Future studies are encouraged to investigate further the cortical processing for possible implications for PD in pain management.
慢性口腔面部疼痛患者常常在没有临床体征的情况下将疼痛的面部区域感知为“肿胀”，这是一种感知扭曲（PD）。在健康参与者中进行局部麻醉（LA）注射也与感知扭曲有关。
目的是探讨在眶下区域注射局部麻醉剂诱发的感知扭曲是否可以通过对受影响区域施加机械刺激（MS）来调节。
用刷子和一根128毫牛顿的von Frey细丝进行机械刺激。首先，60名健康参与者被随机分为三组：（i）局部麻醉对照组，（ii）局部麻醉加机械刺激组，（iii）等渗溶液（ISO）加机械刺激组作为额外的对照条件。为了进一步研究多感觉调制的作用，进行了一项额外的实验。20名参与者除了能看到自己扭曲面部的视觉反馈外，还接受了用细丝进行的局部麻醉加机械刺激。两项实验的结果一并呈现。
所有三个局部麻醉组都出现了感知扭曲；相反，等渗溶液组未报告有感知扭曲。单独的机械刺激并没有改变感知扭曲的程度：刷子刺激（P = 0.089），细丝刺激（P = 0.203）。然而，当细丝刺激与扭曲面部的额外视觉信息相结合时，感知扭曲明显减少（P = 0.002）。
研究结果表明多感觉整合对感知扭曲的重要性，并且在理解可能影响这种常见情况的因素方面向前迈出了重要一步。鼓励未来的研究进一步调查皮层处理过程，以了解其对疼痛管理中感知扭曲的可能影响。
