Table 3.

Association between bone mineral density and the number of teeth

Variables	Total				Number of teeth
					Age 50–64 years				Age ≥65 years
	Totala	N	Mean ± SD	p-value†	Totala	N	Mean ± SD	p-value†	Totala	N	Mean ± SD	p-value†
Normal	3,410	436	23.4 ± 0.6	<0.01	1,767	375	25.2 ± 0.3	0.06	1,643	61	20.4 ± 1.7	0.06
Osteopenia		1,656	20.7 ± 0.3			1,038	23.8 ± 0.3			618	16.4 ± 0.5
Osteoporosis		1,318	18.2 ± 0.3			354	24.0 ± 0.4			964	13.9 ± 0.4
BMDa age_I				<0.01				0.39				0.08

^aExclude missing values

^† p-values obtained from oneway ANOVA using general linear model for complex survey design

age_I: to test interaction by age, participants were categorized into two age groups (50–64 years and ≥65 years).