Pressure pain thresholds are routinely used in orofacial pain research to evaluate the response of deep orofacial tissues to mechanical stimulation. Like other psychophysical measurements, however, this technique must stimulate cutaneous tissues before stimulating deeper tissues.
This study aimed at evaluating the influence of the cutaneous hypoesthesia on the pressure pain threshold in 30 healthy volunteers. PPTs were determined with electric pressure algometry over masseter, temporalis anterior, sternocleidomastoid, and trapezius muscle before and after slan hypoesthesia A local anesthetic cream and a control cream were applied following a pLaQebo-controlled double-blind design and PPTs were reassessed. Two examiners measured PPTs two times on each muscles, randomly. And the EMG activity of all muscles were measured to evaluate the relationship with Mrs. The collected data were processed by SAS/STAT program
The obtained results were as follows
1. There were a tendency to increase PPTs after than before cutaneous hypoesthesia, but there were no significant difference statistically.
2. PPTs were consistently higher in anterior temporalis than in masseter muscle. 3. In all occasions, PPTs were higher in males than in females(P < 0.001).
4. A statistically significant correlation was obtained from values of intea-examiners and inter-examiners in all measured muscles.
5..A significantly positive correlation was not found between PPT and functional EMG activity.
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