Note M - Segment and Geographic Data - Summary of Operations by Geographic Area (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Product sales, net	$ 5,437,236	$ 8,374,501
Dental Segment [Member]
Product sales, net	5,421,436	8,336,901
Medical Segment [Member]
Product sales, net	15,800	37,600
Domestic [Member]
Product sales, net	2,120,186	4,526,604
Domestic [Member] | Dental Segment [Member]
Product sales, net	2,118,186	4,512,904
Domestic [Member] | Medical Segment [Member]
Product sales, net	2,000	13,700
Rest of World [Member]
Product sales, net	3,239,650	3,689,247
Rest of World [Member] | Dental Segment [Member]
Product sales, net	3,225,850	3,665,347
Rest of World [Member] | Medical Segment [Member]
Product sales, net	13,800	23,900
CHINA
Product sales, net	77,400	158,650
CHINA | Dental Segment [Member]
Product sales, net	77,400	158,650
CHINA | Medical Segment [Member]
Product sales, net