Quarterly report pursuant to Section 13 or 15(d)

Note 10 - Significant Concentrations and Geographical Information - Sales by Product and by Geographical Region (Details)

v3.8.0.1
Note 10 - Significant Concentrations and Geographical Information - Sales by Product and by Geographical Region (Details) - USD ($)
3 Months Ended 9 Months Ended
Sep. 30, 2017
Sep. 30, 2016
Sep. 30, 2017
Sep. 30, 2016
Product sales, net $ 2,853,813 $ 3,186,596 $ 9,066,550 $ 8,973,726
Sales Revenue, Goods, Net [Member] | Product Concentration Risk [Member]        
Product sales, net 2,853,813 3,186,596 9,066,550 8,973,726
Domestic [Member] | Sales Revenue, Goods, Net [Member] | Product Concentration Risk [Member]        
Product sales, net 1,358,066 119,416 4,141,129 2,759,376
Domestic [Member] | Sales Revenue, Goods, Net [Member] | Geographic Concentration Risk [Member]        
Product sales, net 1,358,066 119,416 4,141,129 2,759,376
Domestic [Member] | Instruments [Member] | Sales Revenue, Goods, Net [Member] | Product Concentration Risk [Member]        
Product sales, net 452,232 857,525 852,149
Domestic [Member] | Handpieces [Member] | Sales Revenue, Goods, Net [Member] | Product Concentration Risk [Member]        
Product sales, net 893,496 106,908 3,230,567 1,860,593
Domestic [Member] | Other Products [Member] | Sales Revenue, Goods, Net [Member] | Product Concentration Risk [Member]        
Product sales, net 12,338 12,508 53,037 46,634
Europe [Member] | Sales Revenue, Goods, Net [Member] | Product Concentration Risk [Member]        
Product sales, net 1,139,347 2,217,780 3,210,821 4,007,750
Europe [Member] | Instruments [Member] | Sales Revenue, Goods, Net [Member] | Product Concentration Risk [Member]        
Product sales, net 340,575 1,416,030 1,053,050 1,974,280
Europe [Member] | Handpieces [Member] | Sales Revenue, Goods, Net [Member] | Product Concentration Risk [Member]        
Product sales, net 765,821 713,766 2,068,007 1,845,424
Europe [Member] | Other Products [Member] | Sales Revenue, Goods, Net [Member] | Product Concentration Risk [Member]        
Product sales, net 32,951 87,984 89,764 188,046
CHINA | Sales Revenue, Goods, Net [Member] | Product Concentration Risk [Member]        
Product sales, net 356,400 849,400 1,714,600 2,206,600
CHINA | Instruments [Member] | Sales Revenue, Goods, Net [Member] | Product Concentration Risk [Member]        
Product sales, net 493,000 1,000,000 1,493,800
CHINA | Handpieces [Member] | Sales Revenue, Goods, Net [Member] | Product Concentration Risk [Member]        
Product sales, net 356,400 356,400 712,800 712,800
CHINA | Other Products [Member] | Sales Revenue, Goods, Net [Member] | Product Concentration Risk [Member]        
Product sales, net $ 1,800