Institut for Odontologi og Oral Sundhed

TY - JOUR

T1 - Effects of periodontal afferent inputs on corticomotor excitability in humans

AU - Zhang, Y

AU - Boudreau, S

AU - Wang, M

AU - Wang, Kelun

AU - Sessle, B

AU - Arendt-Nielsen, L

AU - Svensson, P

PY - 2010

Y1 - 2010

N2 - The aim of the present study was to determine in humans whether local anaesthesia (LA) or nociceptive stimulation of the periodontal ligaments affects the excitability of the face primary motor cortex (MI) related to the tongue and jaw muscles, as measured by transcranial magnetic stimulation (TMS). Twelve healthy volunteers (11 men, 1 woman, 25.3 +/- 4.2 years) participated in two 3-h sessions separated by 7 days. The LA carbocain or the nociceptive irritant capsaicin was randomly injected into the periodontal ligament of the lower right central incisor. In both sessions, TMS-motor evoked potential (MEP) stimulus-response curves and corticomotor maps were acquired for the tongue and masseter muscles before (baseline) and at 5, 30 and 60 min post-application of carbocain or capsaicin. Transcranial magnetic stimulation-MEP stimulus-response curves were also acquired at these time points for the first dorsal interosseous (FDI) as an internal control. Burning pain intensity and mechanical sensitivity ratings to a von Frey filament applied to the application site were recorded on an electronic visual analogue scale (VAS). All subjects reported a decreased mechanical sensitivity (anova: P = 0.004) in the LA session and a burning pain sensation (VAS peak pain: 6.4 +/- 1.0) in the capsaicin session. No significant changes in cortical excitability of the MI, as reflected by TMS-MEP stimulus-response curves or corticomotor maps for the tongue, masseter or FDI were found between baseline and post-injection for the LA (anovas: P > 0.22) or capsaicin (anovas: P > 0.16) sessions. These findings suggest that a transient loss or perturbation in periodontal afferent input to the brain from a single incisor is insufficient to cause changes in corticomotor excitability of the face MI, as measured by TMS in humans.

AB - The aim of the present study was to determine in humans whether local anaesthesia (LA) or nociceptive stimulation of the periodontal ligaments affects the excitability of the face primary motor cortex (MI) related to the tongue and jaw muscles, as measured by transcranial magnetic stimulation (TMS). Twelve healthy volunteers (11 men, 1 woman, 25.3 +/- 4.2 years) participated in two 3-h sessions separated by 7 days. The LA carbocain or the nociceptive irritant capsaicin was randomly injected into the periodontal ligament of the lower right central incisor. In both sessions, TMS-motor evoked potential (MEP) stimulus-response curves and corticomotor maps were acquired for the tongue and masseter muscles before (baseline) and at 5, 30 and 60 min post-application of carbocain or capsaicin. Transcranial magnetic stimulation-MEP stimulus-response curves were also acquired at these time points for the first dorsal interosseous (FDI) as an internal control. Burning pain intensity and mechanical sensitivity ratings to a von Frey filament applied to the application site were recorded on an electronic visual analogue scale (VAS). All subjects reported a decreased mechanical sensitivity (anova: P = 0.004) in the LA session and a burning pain sensation (VAS peak pain: 6.4 +/- 1.0) in the capsaicin session. No significant changes in cortical excitability of the MI, as reflected by TMS-MEP stimulus-response curves or corticomotor maps for the tongue, masseter or FDI were found between baseline and post-injection for the LA (anovas: P > 0.22) or capsaicin (anovas: P > 0.16) sessions. These findings suggest that a transient loss or perturbation in periodontal afferent input to the brain from a single incisor is insufficient to cause changes in corticomotor excitability of the face MI, as measured by TMS in humans.

U2 - 10.1111/j.1365-2842.2009.02016.x

DO - 10.1111/j.1365-2842.2009.02016.x

M3 - Journal article

C2 - 19889035

VL - 37

SP - 39

EP - 47

JO - Journal of Oral Rehabilitation

JF - Journal of Oral Rehabilitation

SN - 0305-182X

IS - 1

ER -