Significant Customers & Geographical Information - Sales by Product and by Geographical Region (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Product Information [Line Items]
Total sales	$ 2,459,958	$ 2,535,098	$ 6,996,921	$ 7,662,864
Instruments [Member]
Product Information [Line Items]
Total sales	901,213	413,914	2,317,547	1,938,293
Handpieces [Member]
Product Information [Line Items]
Total sales	1,533,936	2,090,580	4,610,592	5,608,776
Other [Member]
Product Information [Line Items]
Total sales	24,809	30,604	68,782	115,795
United States [Member]
Product Information [Line Items]
Total sales	700,879	1,039,153	2,410,054	3,434,171
Canada [Member]
Product Information [Line Items]
Total sales	145,808	30,548	189,164	100,321
Other Foreign [Member]
Product Information [Line Items]
Total sales	$ 1,613,271	$ 1,465,397	$ 4,397,703	$ 4,128,372