Perceptual distortion of the tongue by lingual nerve block and topical application of capsaicin in healthy women.
OBJECTIVE
The aim of this study was to examine reports of perceptual distortion evoked by transient deafferentation and burning pain as models of aspects of burning mouth syndrome (BMS).


METHODS
Sixteen healthy women took part in three experimental sessions that included exposure to lingual nerve block, capsaicin, and control substance. In each session, reported perceptual distortion and mechanical detection threshold (MDT) were assessed at four areas (the tongue, lower front teeth, lower lip, and right thumb) before and at 5, 15, 30 min and 1 and 3 h after the injection or application. A numerical rating scale (NRS) and a template matching procedure were used to quantify the perceptual distortions.


RESULTS
There was a significantly higher MDT on the tongue during the lingual nerve block session at 5 min up until 1 h, with the perceived tongue size significantly increased at 5, 15, and 30 min and at 1 h compared to baseline (P < 0.05). Although the perceived size determined by the NRS scores during the capsaicin session was significantly larger for the lower lip at 5 min compared to baseline (P < 0.001), there were no significant effects on the MDT or the perceived sizes for the tongue, lower front teeth, or right thumb at any of the time points.


CONCLUSIONS
Perceptual distortions of the tongue may be influenced by non-nociceptive somatosensory changes rather than nociceptive activity.


CONCLUSIONS
The perceptual distortion of the tongue was investigated with models of aspects of BMS and may have implications for future studies in clinical populations.
Department of Oral Function and Rehabilitation, Nihon University School of Dentistry at Matsudo, 2-870-1, Sakaecho-nishi, Matsudo, Chiba, 271-8587, Japan. mika.honda49@gmail.com.|Section of Orofacial Pain and Jaw Function, Department of Dentistry, Aarhus University, Aarhus, Denmark. mika.honda49@gmail.com.
Mika
M
Honda
Section of Orofacial Pain and Jaw Function, Department of Dentistry, Aarhus University, Aarhus, Denmark.|Scandinavian Center for Orofacial Neurosciences (SCON), Aarhus, Denmark.
Lene
L
Baad-Hansen
Department of Oral Function and Rehabilitation, Nihon University School of Dentistry at Matsudo, 2-870-1, Sakaecho-nishi, Matsudo, Chiba, 271-8587, Japan.
Takashi
T
Iida
Section of Orofacial Pain and Jaw Function, Department of Dentistry, Aarhus University, Aarhus, Denmark.|Scandinavian Center for Orofacial Neurosciences (SCON), Aarhus, Denmark.
Lilja Kristín
LK
Dagsdóttir
Department of Oral Function and Rehabilitation, Nihon University School of Dentistry at Matsudo, 2-870-1, Sakaecho-nishi, Matsudo, Chiba, 271-8587, Japan.
Osamu
O
Komiyama
Department of Oral Function and Rehabilitation, Nihon University School of Dentistry at Matsudo, 2-870-1, Sakaecho-nishi, Matsudo, Chiba, 271-8587, Japan.
Misao
M
Kawara
Section of Orofacial Pain and Jaw Function, Department of Dentistry, Aarhus University, Aarhus, Denmark.|Scandinavian Center for Orofacial Neurosciences (SCON), Aarhus, Denmark.|Department of Dental Medicine, Karolinska Institutet, Huddinge, Sweden.
Peter
P
Svensson
D000287:Administration, Topical; D000328:Adult; D002054:Burning Mouth Syndrome / Q000503:physiopathology; D002211:Capsaicin / Q000008:administration & dosage*; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D008036:Lingual Nerve; D009407:Nerve Block; D010469:Perceptual Distortion; D014059:Tongue / Q000187:drug effects*
D002211:Capsaicin
Burning mouth syndrome; Capsaicin; Lingual nerve block; Perceptual distortion; Somatosensory change; Tongue