4.

A、B组各组内术后、随访时开门角的比较(x±s)

Comparison of open angles at different timepoints within each group (x±s) /(°)

Segment	Group A			Group B
	Pre-operation	Follow-up	P	Post-operation	Follow-up	P
C3	30.1±5.7	34.0±4.9	0.08	34.5±6.9	31.8±7.1	0.39
C4	28.4±5.3	31.2±6.0	0.20	35.1±6.4	31.7±7.0	0.25
C5	33.5±4.4	33.8±5.0	0.89	34.9±6.4	31.5±5.9	0.21
C6	29.9±6.3	30.6±5.9	0.78	37.9±6.0	34.8±4.1	0.17
C7	32.3±5.2	33.9±5.3	0.09	37.7±8.5	34.2±6.0	0.29