Gingival bleeding and calculus among 12-year-old Chinese adolescents: a multilevel analysis

BMC Oral Health

Table 2 Descriptive characteristics of the participants (N = 4525)

	Number	Percent	95% CI
Gingival bleeding	2110	46.63	45.18	48.08
Calculus	3029	66.94	65.57	68.31
Areas
Pi County	590	13.04	12.06	14.02
Chuanshan District	810	17.90	16.78	19.02
Da County	838	18.52	17.39	19.65
Yibin County	845	18.67	17.54	19.81
Jinniu District	682	15.07	14.03	1.11
Guang’an District	760	16.80	15.71	17.89
Gender
Female	2326	51.40	49.95	52.86
Male	2199	48.60	47.14	50.05
*hukou*
Rural	2320	51.27	49.81	52.73
Urban	2205	48.73	47.27	50.19
Ethnicity
Han	4475	98.90	98.59	99.20
Others	50	1.10	2.80	1.41
Family size
One child	2883	63.71	62.31	65.11
More than one child	1642	36.29	34.89	37.69
Father’s educational level
Middle school or lower ^a	2960	65.41	64.03	66.80
More than middle school^b	1565	34.59	33.20	35.97
Mother’s educational level
Middle school or lower ^a	3314	73.24	71.95	74.53
More than middle school^b	1211	26.76	25.47	28.05
Toothbrushing frequency
Never	329	7.27	6.51	8.03
Sometimes	670	14.81	13.77	15.84
1	1925	42.54	41.10	43.98
≥ 2	1601	35.38	33.99	36.77
Dental floss usage
Never	4273	94.43	93.76	95.10
Yes	252	5.57	4.90	6.24
Candy/chocolate /cookies /cakes
≤ 1/week	1820	40.22	38.79	41.65
> 1/week	2705	59.78	58.35	61.21
Sugar-containing soft drink/soda/ milk/yogurt /tea/coffee/water
≤ 1/week	2999	66.28	64.90	67.65
> 1/week	1526	33.72	32.35	35.10
Dentist visit during past year
> 0	991	21.90	20.70	23.11
0	3534	78.10	76.89	79.30
Frequency of dental education (previous semester)
> 0	537	11.87	10.92	12.81
0	3988	88.13	87.19	89.08

Abbreviation: ^aMiddle school or lower, ≤9 years; ^bMore than middle school, >9 years

ISSN: 1472-6831