Note 10 - Segment and Geographic Data - Summary of Operations by Geographic Area (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Product sales, net	$ 2,215,699	$ 2,108,233	$ 6,564,969	$ 7,458,678
Dental Segment [Member]
Product sales, net	2,206,499	2,076,233	6,509,619	7,334,628
Medical Segment [Member]
Product sales, net	9,200	32,000	55,350	124,050
Domestic [Member]
Product sales, net	876,318	790,382	2,826,761	2,788,083
Domestic [Member] | Dental Segment [Member]
Product sales, net	867,118	778,882	2,791,411	2,768,433
Domestic [Member] | Medical Segment [Member]
Product sales, net	9,200	11,500	35,350	19,650
Rest of World [Member]
Product sales, net	1,339,381	956,996	3,378,244	3,277,404
Rest of World [Member] | Dental Segment [Member]
Product sales, net	1,339,381	936,496	3,358,244	3,173,004
Rest of World [Member] | Medical Segment [Member]
Product sales, net	0	20,500	20,000	104,400
CHINA
Product sales, net	0	360,855	359,964	1,393,191
CHINA | Dental Segment [Member]
Product sales, net	0	360,855	359,964	1,393,191
CHINA | Medical Segment [Member]
Product sales, net	0	0	0	0
Instruments [Member] | Domestic [Member]
Product sales, net	171,841	36,480	449,836	391,250
Instruments [Member] | Domestic [Member] | Dental Segment [Member]
Product sales, net	164,341	36,480	442,336	391,250
Instruments [Member] | Domestic [Member] | Medical Segment [Member]
Product sales, net	7,500	0	7,500	0
Instruments [Member] | Rest of World [Member]
Product sales, net	436,069	257,563	1,050,443	855,403
Instruments [Member] | Rest of World [Member] | Dental Segment [Member]
Product sales, net	436,069	253,063	1,050,443	792,903
Instruments [Member] | Rest of World [Member] | Medical Segment [Member]
Product sales, net	0	4,500	0	62,500
Instruments [Member] | CHINA
Product sales, net	0	0	0	228,000
Instruments [Member] | CHINA | Dental Segment [Member]
Product sales, net	0	0	0	228,000
Instruments [Member] | CHINA | Medical Segment [Member]
Product sales, net	0	0	0	0
Handpieces [Member] | Domestic [Member]
Product sales, net	680,173	732,649	2,301,615	2,338,699
Handpieces [Member] | Domestic [Member] | Dental Segment [Member]
Product sales, net	678,473	721,149	2,275,865	2,319,049
Handpieces [Member] | Domestic [Member] | Medical Segment [Member]
Product sales, net	1,700	11,500	25,750	19,650
Handpieces [Member] | Rest of World [Member]
Product sales, net	881,616	690,133	2,285,367	2,379,592
Handpieces [Member] | Rest of World [Member] | Dental Segment [Member]
Product sales, net	881,616	674,133	2,265,367	2,337,692
Handpieces [Member] | Rest of World [Member] | Medical Segment [Member]
Product sales, net	0	16,000	20,000	41,900
Handpieces [Member] | CHINA
Product sales, net	0	360,855	359,964	1,165,191
Handpieces [Member] | CHINA | Dental Segment [Member]
Product sales, net	0	360,855	359,964	1,165,191
Handpieces [Member] | CHINA | Medical Segment [Member]
Product sales, net	0	0	0	0
Accessories [Member] | Domestic [Member]
Product sales, net	24,304	21,253	75,310	58,134
Accessories [Member] | Domestic [Member] | Dental Segment [Member]
Product sales, net	24,304	21,253	73,210	58,134
Accessories [Member] | Domestic [Member] | Medical Segment [Member]
Product sales, net	0	0	2,100	0
Accessories [Member] | Rest of World [Member]
Product sales, net	21,696	9,300	42,434	42,409
Accessories [Member] | Rest of World [Member] | Dental Segment [Member]
Product sales, net	21,696	9,300	42,434	42,409
Accessories [Member] | Rest of World [Member] | Medical Segment [Member]
Product sales, net	0		0	0
Accessories [Member] | CHINA
Product sales, net	0	0	0	0
Accessories [Member] | CHINA | Dental Segment [Member]
Product sales, net	0		0	0
Accessories [Member] | CHINA | Medical Segment [Member]
Product sales, net	$ 0	$ 0	$ 0	$ 0