Table 2.

Univariate and multivariate analysis of anterior ETT restored with resin composite (n=157)

Factors	Teeth ( n )	Survival (%)	Univariate Analysis				Multivariate analysis
			HR (95% CI)		P -value		Adjusted HR (95%CI)			P -value
Gender
Female	96	88 (91.7)	1		0.44			NA		NA
Male	61	54 (88.5)	1.49 (0.54, 4.15)
Tooth type
Incisor	109	101 (92.7)	0.44 (0.16, 1.22)		0.12*			1.784 (0.273, 11.679)		0.55
Canine	48	41 (85.4)	1					1
Location
Maxillary	126	113 (89.7)	2.20 (0.49, 9.79)		0.30			NA		NA
Mandible	31	29 (93.5)	1
Restorative surfaces
1–3	130	121 (93.1)	1		<0.01*			1		0.44
4–5	27	21 (77.8)	4.76 (1.68,13.52)					1.780 (0.407, 7.782)
Remaining cervical tooth structure (walls)
0–2	61	50 (82)	3.69 (1.18, 11.62)		0.03*			8.947 (1.429, 56.012)		0.02*
3–4	96	92 (95.8)	1					1
Posterior teeth support (side)
None	13	7 (53.8)		20.43 (5.72, 72.92)		<0.01*			9.053 (1.680, 48.772)	0.02*
1	32	27 (84.4)		4.08 (1.09, 15.23)		<0.01*			0.609 (0.095, 3.921)	0.61
2	112	108 (96.4)		1					1
Adjacent teeth (n)
None and 1	34	27 (79.4)	5.03 (1.81, 13.99)		<0.01*			3.487 (0.671, 18.111)		0.14
2	123	115 (93.5)	1					1
Cervical root dentin thickness (ratio)
< 1:1:1	98	86 (87.8)	2.87 (0.81, 10.21)		0.10*			12.979 (1.549, 108.734)		0.02*
≥ 1:1:1	59	56 (94.9)	1					1
Parafunctional habit
Yes	25	20 (80)	2.76 (0.83, 9.19)		0.10*			19.366 (2.250, 166.708)		<0.01*
No	105	99 (94.3)	1					1

^* A significant difference was indicated by the log-rank test (P<0.05) in the comparison of survival rates among the potential risk factors.

The factors with P value≤0.25 were further analyzed using the multivariate model. HR, hazard ratio