Table 6.

Age-related distances between root apex and the maxillary sinus floor in the second molar.

Tooth	Age	N	Sagittal				Coronal
			Mean ± SD	Min	Max	P value	Mean ± SD	Min	Max	P value
MB	≤20①	62	−0.16 ± 2.16	−2.92	10.27	P(①,②) = 0.017	−0.23 ± 1.98	−2.03	9.38	P(①,②) = 0.003
	21–40②	82	0.75 ± 2.23	−3.54	8.78	P(②,③) = 0.001	0.88 ± 2.24	−3.29	8.14	P(②,③) < 0.001
	41–60③	66	2.06 ± 2.74	−1.72	10.76	P(①,③) < 0.001	2.21 ± 2.69	−1.02	11.29	P(①,③) < 0.001
DB	≤20①	62	0.40 ± 2.42	−2.47	10.33	P(①,②) = 0.648	0.48 ± 2.46	−1.88	9.66	P(①,②) = 0.583
	21–40②	82	1.13 ± 2.66	−3.54	10.80	P(②,③) < 0.001	1.36 ± 2.64	−2.74	10.94	P(②,③) < 0.001
	41–60③	66	2.88 ± 3.01	−1.72	12.91	P(①,③) < 0.001	3.07 ± 2.99	−0.96	12.40	P(①,③) < 0.001
P	≤20①	62	1.03 ± 2.26	−2.10	10.40	P(①,②) = 0.624	1.44 ± 2.33	−1.33	9.22	P(①,②) = 0.657
	21–40②	82	2.39 ± 3.24	−3.54	10.96	P(②,③) < 0.001	2.83 ± 3.16	−2.45	11.54	P(②,③) = 0.039
	41–60③	66	3.88 ± 3.58	−1.72	16.97	P(①,③) < 0.001	3.96 ± 3.35	−1.02	16.02	P(①,③) < 0.001

Distances are shown in mm. Circled numbers indicate age groups as shown in “Age” column.

Abbreviations: MB, mesiobuccal root; DB, distobuccal root; P, palatal root; N, number; SD, standard deviation; Min, minimum; Max, maximum.