Table 7.

Screw loosening according to implant prosthesis type and opposing teeth

		Screw loosening		χ2	P-value
		No	Yes
Type of prosthesis	Implant-retained overdenture	32 (100)	0 (0)	77.392	0.000*
	Splinted crown	1,148 (96.6)	40 (3.4)
	Cantilever bridge	15 (88.2)	2 (11.8)
	Single crown	594 (86.0)	97 (14.0)
Opposing tooth	Denture	61 (100)	0 (0.0)	6.325	0.097
	Fixed prosthesis	357 (93.9)	23 (6.1)
	Implant-supported prosthesis	331 (92.5)	27 (7.5)
	Natural tooth	1,040 (92.1)	89 (7.9)

^* P<0.05.

Values are presented as number of implants (%).