CBCT Analysis of Edentulous Mandibular Symphysis in Iraqi Patients for Treatment with Implant-Supported Overdentures. Cross-Sectional Single-Center Study

Figures & data

Figure 1 The symphysis section and the studied measurements. a-Cortical thickness; P1, the crest of the ridge; P6, the base of the mandible; P2, the upper buccal; P3, the upper lingual; P4, the lower buccal; and P5, the lower lingual. b-HL, the total height; W1, width of the upper third; and W2, width of the lower third. c-densities of the bones were measured at positions P1, P6, P7, and P8.

Table 1 Comparison of Bone Dimensions and Density of the Mandible Symphysis Between Males (n=45) and Females (n=45)

Variables	Sites	Male	Female	Total	P-value
Age		59±8.46	47±6.80	53± 9.86	0.001*
Cortical thickness	P1	1.75±0.60	1.88±0.84	±0.731.81	0.21
	P2	2.13±0.80	1.75±0.70	±0.771.94	0.01*
	P3	2.13±0.63	2.04±0.8	±0.722.08	0.27
	P4	2.76±0.87	2.35±0.85	±0.882.55	0.01*
	P5	2.89±0.84	2.68±0.76	±0.812.78	0.11
	P6	3.33±1.03	3.02±0.97	±1.013.17	0.07
Width	W1	9.66±2.97	8.61±1.98	9.13±2.57	0.03*
	W2	12.83±2.89	11.79±2.30	12.3±2.65	0.03*
Height	HL	26.66±6.21	24.07±5.00	25.37±5.8	0.02*
Bone density	P1	865.31±221.36	863.44±231.57	864.38±225.3	0.48
	P7	728.82±197.92	719.16±205.95	723.99±200.9	0.41
	P8	787.04±221.25	866.07±268.12	826.56±247.63	0.07
	P6	1263.07±309.44	1269.62±325.28	1266.34±315.69	0.46

Notes: *Statistically significant. Thickness points include P1: ridge peak, P2: upper buccal, P3: upper lingual, P4: lower buccal, P5: lower lingual, P6: base of the mandible. Widths points include W1: upper third and W2: lower third of the mandibular ridge. Bone density was measured at cortical bone (P1, P6) and at the cancellous bone (P7, P8). The results represent mean±Standard deviation (SD).

Table 2 Comparison of Cortical Thickness for All Subjects (Males and Females)

Cortical Bone Thickness				P-value
P1	±0.731.81	P6	±1.013.17	0.001*
P2	±0.771.94	P3	±0.722.08	0.1
P4	±0.882.55	P5	±0.812.78	0.03*

Notes: *Statistically significant. P1: ridge peak, P2: upper buccal, P3: upper lingual, P4: lower buccal, P5: lower lingual, P6: base of the mandible (n=90). The results represent mean±Standard deviation (SD).

Table 3 Correlation Between Bone Height (HL) and Both of Bone Density and Width at the Symphyseal Region (n=90)

	Site	Height	r	p-value
P1-HL	864.38±225.3	25.37±5.8	−0.03	0.75
P7-HL	723.99±200.9	25.35±5.8	−0.01	0.97
P8-HL	826.56±247.63	25.35±5.8	0.08	0.43
P6-HL	1266.34±315.69	25.35±5.8	0.3	0.014*
W1-HL	9.13±2.57	25.37±5.8	0.3	0.004*
W2-HL	12.3±2.65	25.37±5.8	0.6	0.0001*

Notes: *Statistically significant. W1, width of the upper third; and W2, width of the lower third. P1, P6, P7, P8: positions of bone densities measurements. The Results Represent mean±Standard Deviation (SD).

Table 4 The Gender Distribution of Cawood and Howell Classifications of the Symphysis

Class	Male		Female		Total
	Frequency	Percentage	Frequency	Percentage	Frequency	Percentage
III	30	66.7	29	64.4	59	65.6
IV	12	26.7	10	22.2	22	24.4
V	3	6.7	2	4.4	5	5.6
VI	0	0	4	8.9	4	4.4
Total	45	100	45	100	90	100

Figure 2 According to gender, the distribution of Cawood and Howell classes (45 males and 45 females). Due to the criteria of our study, no patients from classes I or II were allowed to take part.

Data Sharing Statement

The data used to support the findings of this study are available from the corresponding author upon request.