Table 1. Location of facial pain threshold survey points

Neural Regulation	Point	Area	Specific location
V1	Above	Head	Left = 1 cm left and 1 cm anterior of the vertex (intersection of the line connecting the tops of the auricle and the longitudinal center of the head).
			Right = 1 cm right and 1 cm anterior of the vertex (intersection of the line connecting the tops of the auricle and the longitudinal center of the head)
	Middle	Forehead	Left = 1 cm above the centre of the left
			eyebrow Right = 1 cm above the centre of the right eyebrow
	Below	Nose	Left = 1 cm left of the tip of the nose
			Right = 1 cm right of the tip of the nose
V2	Above	Forehead	Left = 2 cm to the left of the left outer corner of the left eye
			Right = 2 cm to the right of the right outer corner of the right eye
	Middle	Cheek	Left = the intersection of the horizontal line from the side of the left nose and the straight line from the outer corner of the left eye
			Right = the intersection of the horizontal line from the side of the right nose and the straight line from the outer corner of the right eye
	Below	Perioral area	Left = 1 cm to the left of the bottom of the philtrum
			Right = 1 cm to the right of the bottom of the philtrum
V3	Above	Head	Left = 5 cm above the left helix
			Right = 5 cm above the right helix
	Middle	Jawline	Left = the outer left of the jawbone
			Right = the outer right of the jawbone
	Below	Chin	Left = 1 cm to the left of the bottom of the chin
			Right = 1 cm to the right of the bottom of the chin