Radiographic evaluation of third molar genesis in Greek orthodontic patients

Figures & data

Figure 1 Age and sex distribution of the sample.

Table 1 Presence of third molars (M3 teeth) according to age and sex

Age, years	Sex	Presence of each of the four M3 teeth, n				Total number of M3 teeth present at each age
		18	28	38	48
5+	Male	0	0	0	0	0
	Female	0	0	0	0	0
	Total	0	0	0	0	0
6+	Male	0	0	0	0	0
	Female	0	0	0	0	0
	Total	0	0	0	0	0
7+	Male	0	0	0	0	0
	Female	3 (100%)	2 (100%)	2 (100%)	3 (100%)	10
	Total	3	2	2	3	10
8+	Male	7 (43.8%)	7 (43.8%)	8 (42.1%)	8 (44.4%)	30
	Female	9 (56.3%)	9 (56.3%)	11 (57.9%)	10 (55.6%)	39
	Total	16	16	19	18	69
9+	Male	16 (53.3%)	16 (55.2%)	18 (50%)	18 (48.6%)	68
	Female	14 (46.7%)	13 (44.8%)	18 (50%)	19 (51.4%)	64
	Total	30	29	36	37	132
10+	Male	12 (28.6%)	11 (26.2%)	13 (27.1%)	14 (29.8%)	50
	Female	30 (71.4%)	31 (73.8%)	35 (72.9%)	33 (70.2%)	129
	Total	42	42	48	47	179
11+	Male	31 (44.9%)	32 (45.7%)	30 (44.1%)	30 (44.1%)	123
	Female	38 (55.1%)	38 (54.3%)	38 (55.9%)	38 (55.9%)	152
	Total	69	70	68	68	275
12+	Male	22 (42.3%)	20 (40%)	22 (43.1%)	21 (40.4%)	85
	Female	30 (57.7%)	30 (60%)	29 (56.9%)	31 (59.6%)	120
	Total	52	50	51	52	205
13+	Male	20 (44.4%)	20 (44.4%)	26 (50%)	24 (48%)	90
	Female	25 (55.6%)	25 (55.6%)	26 (50%)	26 (52%)	102
	Total	45	45	52	50	192
14+	Male	15 (42.9%)	17 (45.9%)	16 (43.2%)	17 (47.2%)	65
	Female	20 (57.1%)	20 (54.1%)	21 (56.8%)	19 (52.8%)	80
	Total	35	37	37	36	145
15+	Male	5 (26.3%)	5 (26.3%)	4 (23.5%)	5 (27.8%)	19
	Female	14 (73.7%)	14 (73.7%)	13 (76.5%)	13 (72.2%)	54
	Total	19	19	17	18	73
16+	Male	10 (41.7%)	11 (44%)	10 (43.5%)	10 (41.7%)	41
	Female	14 (58.3%)	14 (56%)	13 (56.5%)	14 (58.3%)	55
	Total	24	25	23	24	96
17+	Male	2 (28.6%)	2 (28.6%)	2 (28.6%)	2 (33.3%)	8
	Female	5 (71.4%)	5 (71.4%)	5 (71.4%)	4 (66.7%)	19
	Total	7	7	7	6	27
18+	Male	2 (100%)	2 (100%)	2 (100%)	2 (100%)	8
	Female	0	0	0	0	0
	Total	2	2	2	2	8
Total	Male	142 (41.3%)	143 (41.6%)	151 (41.7%)	151 (41.8%)	587
	Female	202 (58.7%)	201 (58.4%)	211 (58.3%)	210 (58.2%)	824
	Total	344	344	362	361	1411

Table 2 Number of third molars (M3 teeth) per person and according to sex

	Number of M3 teeth					Total	P
	0	1	2	3	4
Sex
Male
N	15	3	21	18	122	179
% of total	3.5%	0.7%	4.9%	4.2%	28.5%	41.8%	0.260
Female
N	21	5	31	11	181	249
% of total	4.9%	1.2%	7.2%	2.6%	42.3%	58.2%
Total
N	36	8	52	29	303	428
% of total	8.4%	1.9%	12.1%	6.8%	70.8%	100.0%

Table 3 Number of maxillary, mandibular, right-, and left-side third molar (M3 teeth)

M3 teeth	Sex		Total	P
	Male	Female
Maxillary (18, 28)
Absent	73 (8.5%)	95 (11.1%)	168 (19.6%)	0.663
Present	285 (33.3%)	403 (47.1%)	688 (80.4%)
Mandibular (38, 48)
Absent	56 (6.5%)	77 (9.0%)	133 (15.5%)	1.000
Present	302 (25.3%)	421 (49.2%)	723 (84.5%)
Right side (18, 48)
Absent	65 (7.6%)	86 (10%)	151 (17.6%)	0.785
Present	293 (34.2%)	412 (48.1%)	705 (82.4%)
Left side (28, 38)
Absent	64 (7.5%)	86 (10%)	150 (17.5%)	0.856
Present	294 (34.3%)	412 (48.1%)	706 (82.5%)

Table 4 Number of patients with varying degrees of absent third molars (M3 teeth) in the maxilla and the mandible, and on the right and the left side

(M3 teeth)	Sex		Total	P
	Male	Female
Maxillary
Both absent	30 (7.0%)	44 (10.3%)	74 (17.3%)	0.096
One absent	13 (3.0%)	7 (1.6%)	20 (4.6%)
None absent	136 (31.8%)	198 (46.3%)	334 (78.1%)
Mandibular
Both absent	21 (4.9%)	31 (7.2%)	52 (12.1%)	0.772
One absent	14 (3.3%)	15 (3.5%)	29 (6.8%)
None absent	144 (33.6%)	203 (47.4%)	347 (81.1%)
Right side
Both absent	18 (4.2%)	25 (5.8%)	43 (10.0%)	0.880
One absent	29 (6.8%)	36 (8.4%)	65 (15.2%)
None absent	132 (30.8%)	188 (43.9%)	320 (74.8%)
Left side
Both absent	17 (4.0%)	24 (5.6%)	41 (9.6%)	0.919
One absent	30 (7.0%)	38 (8.9%)	68 (15.9%)
None absent	132 (30.8%)	187 (43.7%)	319 (74.5%)