Abstract
Background
This study aimed to evaluate buccal and lingual alveolar bone thickness of maxillary and mandibular anterior teeth and to investigate the prevalence of dehiscence and fenestration across skeletal Class I, II, and III malocclusions using cone-beam computed tomography (CBCT).
Methods
A total of 252 individuals (84 per group; Class I, II, and III) aged 14–35 years were included. CBCT axial and sagittal slices were analyzed to measure alveolar bone thickness at three root levels (cervical, middle, and apical thirds). Dehiscence and fenestration were diagnosed according to standard criteria. Statistical analyses were performed using one-way ANOVA, Kruskal–Wallis, Tukey’s HSD, and chi-square tests, with significance set at p < 0.05.
Results
No statistically significant difference in bone thickness was observed among Class I, Class II, and Class III malocclusions. The presence of dehiscence was found to be more common in Class I and Class III individuals than in Class II individuals (p = 0.029). The presence of fenestration was higher in individuals with Class III and Class II malocclusions than in individuals with Class I malocclusions (p = 0.032).
Conclusions
Alveolar bone thickness of anterior teeth did not differ among skeletal malocclusion groups. Nevertheless, the prevalence of dehiscence and fenestration varied significantly, with Class II showing less dehiscence, and Class II and III demonstrating higher fenestration. These findings highlight the need for careful CBCT-based assessment of alveolar morphology in orthodontic planning, particularly for camouflage treatments involving anterior tooth movement.
Clinical trial registration number
Not applicable.
Keywords: Skeletal malocclusion, Alveolar bone thickness, Dehiscence, Fenestration, CBCT imaging
Background
The position of teeth within the alveolar bone is determined by a dynamic equilibrium involving occlusal forces, tongue posture and surrounding soft tissues [1–3]. Orthodontic treatment is a process that alters and then reestablishes this equilibrium by repositioning teeth, particularly incisors, within the alveolar bone surrounds them [4]. However, the movement of incisors in the sagittal direction is limited by the anatomical constraints of the alveolar bone [5]. Excessive tooth movement beyond these limits may result in reduced bone thickness and increase the risk of alveolar bone defects such as dehiscence and fenestration [6].
Dehiscence is defined as a loss of alveolar bone along the root surface that extends from the crest apically, resulting in exposure of the cervical root, whereas fenestration refers to a localized window-like bone defect over the root surface with an intact alveolar crest [7]. These defects are of clinical concern due to their potential implications for periodontal health, especially during and after orthodontic tooth movement [8]. Although it was previously stated that destructive periodontal effects may occur in the alveolar bone with orthodontic treatment, today, there is no consensus on this topic [9].
Incisor inclination and position vary among different malocclusion types and may influence the buccal and lingual cortical bone thickness [10, 11]. Incisors deviate from normal range when there’s reduced cortical support, increasing the risk of dehiscence and fenestration [11]. In a CBCT study of Class I and Class II Division 2 cases, Evangelista et al. [12] reported a combined prevalence of dehiscence/fenestration of approximately 51%. Across various sagittal and vertical malocclusions, such bone defects appear common prior to orthodontic treatment, yet their etiology remains debated [6, 12–14]. Due to the potential risks of periodontal disease during orthodontic treatment, the initial position of the teeth and the thickness of the alveolar bone must be carefully assessed [6].
Previous CBCT studies often analyzed alveolar bone thickness using sagittal and coronal sections, which may yield false-negative results due to imaging limitations such as angulation errors and partial volume effects [15]. Conversely, axial CBCT slices have shown higher reliability in detecting thin buccal and lingual cortices [16, 17]. Existing axial-slice studies have often been limited by small samples and a predominant focus on Class III subjects [15–17]. Previous CBCT studies have reported alveolar bone defects in different malocclusion groups, including Class I–II [12], Class III [18], and Class I–III with limited scope [14, 19]. While previous studies such as that of Yagci et al. have examined dehiscence and fenestration across different skeletal malocclusions, few have simultaneously assessed both alveolar bone thickness and the prevalence of these cortical defects across three root levels and skeletal classes using axial CBCT imaging.
Therefore, this study used cone-beam computed tomography (CBCT) axial slices to measure buccal and lingual alveolar bone thickness of anterior teeth and to evaluate the presence of dehiscence and fenestration across skeletal Class I–III malocclusions. We tested two null hypotheses: (H01) there is no difference in buccal or lingual alveolar bone thickness of incisors among various malocclusion; and (H02) there is no difference in the prevalence of dehiscence or fenestration among various malocclusion.
Methods
Ethical approval and study design
This retrospective study was approved by the Van Yüzüncü Yıl University Non-Interventional Clinical Research Ethics Committee (2022/12 − 02). The study adhered to the principles of the Declaration of Helsinki, and written informed consent was obtained from all individuals. The study flow chart is presented in Fig. 1.
Fig. 1.
Flowchart of the research
Sample size calculation
A priori sample size calculation was performed using G*Power software (v3.1, Franz Faul, University of Kiel, Germany). Assuming an effect size of 0.25, α = 0.05, and 95% power, the required sample size was determined to be 84 participants per group (Class I, II, III), totaling 252 individuals [20].
Sample selection and eligibility criteria
CBCT records obtained for diagnostic purposes between January 2018 and December 2022 at the Department of Oral and Maxillofacial Radiology, XXX University, were screened. In order to minimize potential confounding factors associated with alveolar bone dehiscence and fenestration, strict inclusion and exclusion criteria were applied. Tooth-related factors were controlled by excluding individuals with rotated incisors greater than 10°, missing permanent teeth (except third molars), supernumerary teeth, impacted teeth, or prosthetic replacements. The investigation focused on bone-related factors by limiting the sample to subjects with an SN-GoGn angle of 31° ± 5°. This approach served to mitigate the impact of vertical skeletal anomalies, thereby ensuring the robustness of the study. Additionally, subjects with horizontal or vertical bone loss, craniofacial anomalies, cysts, or tumors were excluded from the study, thus ensuring a comprehensive and controlled experimental setting. The impact of periodontal factors was mitigated by excluding individuals who had undergone periodontal surgery, exhibited interproximal bone crest measurements greater than 2 millimeters apical to the cemento-enamel junction, or demonstrated active root resorption. A multitude of additional factors were taken into consideration as well. Patients with systemic diseases affecting bone metabolism, previous orthodontic or orthognathic treatment, and low-quality CBCT images with artifacts were excluded from the study. Furthermore, the standardization of incisor position was achieved by the inclusion of cases with upper incisor inclination ranging from 20° to 24° (U1-NA) and lower incisor inclination between 23° and 27° (L1-NB).
CBCT acquisition protocol
CBCT scans were acquired using a KaVo 3D eXam system (Biberach, Germany) with the following parameters: 120 kVp, 5 mAs, 0.125–0.4 mm voxel size, 130 mm FOV, and 7 s scan time. The scans were taken with patients in centric occlusion, Frankfort horizontal plane parallel to the floor, and stabilized using chin support and cephalostats. Orientation corrections for yaw, roll, and pitch were applied using standard landmarks (Ba, Na, PoR, OrR).
Bone thickness measurements
Measurements were performed using eXam Vision software. In sagittal sections, the long axis of each tooth was divided into thirds: Coronal 1/3: B1 (buccal), L1 (lingual); Middle 1/3: B2, L2; Apical 1/3: B3, L3. In axial sections, linear measurements were made perpendicular to the tooth axis from both buccal and lingual sides. Measurement points are detailed in Fig. 2.
Fig. 2.
For bone thickness, the long axis of the tooth passing through the apical of the tooth was divided into three sections (coronal1/3, middle1/3 and apical1/3) in the sagittal section (a, b, c). In the axial section, linear measurements (red straight line) were made perpendicular to the long axis of the tooth (d, e, f)
Assessment of dehiscence and fenestration
Dehiscence was defined as bone loss > 2 mm from the CEJ to alveolar crest. Fenestration was defined as an isolated bone defect that did not involve the crest (Fig. 3). The entire root surface was examined in both sagittal and axial views. Absence of cortical bone covering the root indicated presence of bone defects.
Fig. 3.
a Axial image for fenestration in the maxilla (b) Axial and cross-sectional image of dehiscence in the maxilla (c) Axial and cross-sectional image of fenestration in the maxilla
Observer protocol and reliability
All measurements were performed by a single oral and maxillofacial radiologist with five years of experience, blinded to skeletal classification. Observations were made in a dark room using a 23-inch monitor, with a maximum analysis time of 3 h per day to reduce visual fatigue. For intraobserver reliability, 10% of cases were randomly remeasured at two time intervals: four weeks and one year after initial analysis. The agreement between measurements was assessed and presented as supplementary information.
Statistical analysis
All statistical analyses were conducted using IBM SPSS Statistics version 23.0 (IBM Corp., Armonk, NY, USA). The normality of continuous variables was assessed using the Kolmogorov–Smirnov test. For variables with normal distribution, comparisons among the three skeletal malocclusion groups were performed using one-way analysis of variance (ANOVA), and post-hoc comparisons were conducted using Tukey’s honestly significant difference (HSD) test. For non-normally distributed data, the Kruskal–Wallis test was used to compare the groups. Categorical variables such as the presence of dehiscence or fenestration were compared using the chi-square (χ²) test. Quantitative variables were presented as mean ± standard deviation for normally distributed data and median (minimum–maximum) for non-normally distributed data, while categorical variables were presented as frequencies and percentages. A p value of < 0.05 was considered statistically significant.
Results
The demographic characteristics of the participants are summarized in Table 1. Cronbach’s Alpha values for intra-examiner reliability in measuring alveolar bone thickness, dehiscence, and fenestration ranged from 0.941 to 0.973, indicating excellent reproducibility. Bland–Altman analysis was performed on 27 randomly selected individuals after one year (Fig. 4), demonstrating high agreement and minimal measurement error: for maxillary buccal bone (LOA: −0.013 to 0.0098, p = 0.838), maxillary lingual bone (LOA: −0.024 to 0.021, p = 0.784), mandibular buccal bone (LOA: −0.023 to 0.019, p = 0.321), and mandibular lingual bone (LOA: −0.023 to 0.018, p = 0.634).
Table 1.
Comparison of demographic characteristics by classes
| Gender | Class I(%) | Class II(%) | Class III(%) | Total(%) | p |
|---|---|---|---|---|---|
| Female (n) | 54 (65.8) | 51 (62.9) | 39 (48.1) | 144 (59.0) | 0.06* |
| Male (n) | 28 (34.2) | 30 (37.1) | 42 (51.9) | 100 (41.0) | |
| Age (M-SD) | 23.66 ± 5.48 | 23.97 ± 6.92 | 23.77 ± 5.95 | 23.88 ± 6.12 | 0.90** |
n number of individuals, M-SD Mean ± Standart deviation
*Chi-square test
**One-way analysis of variance, frequency (percentage)
p < 0.05
Fig. 4.
Bland-altman analysis
Comparisons of buccal and lingual bone thicknesses across skeletal malocclusion groups are presented in Table 2. Although slight variations were observed among groups, no statistically significant differences were found in either the maxilla or the mandible.
Table 2.
Comparison of bone thicknesses on each surface of the maxilla and mandible according to classes
| Class I (Mean-SD) |
Class II (Mean-SD) |
Class III (Mean-SD) |
p | ||
|---|---|---|---|---|---|
|
Maxilla (mm) (n = 1512) |
B1 | 0.66 ± 0.58 | 0.68 ± 0.61 | 0.67 ± 0.65 | 0.191 |
| B2 | 1.33 ± 1.3 | 1.30 ± 1.25 | 1.34 ± 1.33 | 0.150 | |
| B3 | 2.07 ± 2.5 | 1.93 ± 2.44 | 2.11 ± 2.59 | 0.065 | |
| L1 | 1.18 ± 0.91 | 1.15 ± 0.87 | 1.16 ± 0.91 | 0.425 | |
| L2 | 2.12 ± 1.5 | 2.24 ± 1.67 | 2.11 ± 1.62 | 0.121 | |
| L3 | 4.4 ± 3.19 | 4.70 ± 3.37 | 4.56 ± 3.27 | 0.616 | |
|
Mandible(mm) (n = 1512) |
B1 | 0.47 ± 0.54 | 0.44 ± 0.48 | 0.46 ± 0.52 | 0.136 |
| B2 | 0.69 ± 0.69 | 0.66 ± 0.67 | 0.64 ± 0.72 | 0.473 | |
| B3 | 1.77 ± 1.12 | 1.79 ± 1.15 | 1.75 ± 1.19 | 0.323 | |
| L1 | 0.55 ± 0.54 | 0.56 ± 0.55 | 0.56 ± 0.59 | 0.898 | |
| L2 | 1.06 ± 0.91 | 0.99 ± 0.80 | 1.04 ± 0.88 | 0.416 | |
| L3 | 1.23 ± 0.77 | 2.10 ± 1.11 | 2.17 ± 1.24 | 0.356 | |
Kruskal-Wallis test, SD Standart deviation, n number of teeth, mm millimeter p < 0.05
The prevalence of dehiscence across different skeletal malocclusion types is presented in Table 3, while the prevalence of fenestration is summarized in Table 4. Dehiscence was significantly less frequent in Class II malocclusions (7.3%) compared to Class I (9.5%) and Class III (9.1%) (p = 0.029). Fenestration was significantly more frequent on the lingual surfaces in Class II (2.5%) and Class III (2.8%) compared to Class I (1.4%) (p = 0.011). In addition, overall fenestration in region 2 was higher in Class II (2.7%) and Class III (3.0%) than in Class I (1.2%) (p = 0.001). Furthermore, the total prevalence of fenestration was also significantly higher in Class II and III compared to Class I (p = 0.032).”
Table 3.
Comparison of the presence of dehiscence by classes
| Dehiscence | Class I | Class II | Class III | Total | p | |
|---|---|---|---|---|---|---|
| Buccal | yes | 106 (10.9) | 81 (8.1) | 94 (9.6) | 281 (9.5) | 0.093 |
| no | 864 (89.1) | 925 (91.9) | 889 (90.4) | 2678 (90.5) | ||
| Lingual | yes | 79 (8.1) | 66 (6.5) | 85 (8.6) | 230 (7.8) | 0.190 |
| no | 892 (91.9) | 942 (93.5) | 899 (91.4) | 2733 (92.2) | ||
| Total | yes | 185 (9.5)a | 147 (7.3)b | 179 (9.1)ab | 511 (8.6) | 0.029* |
| no | 1756 (90.5) | 1867 (92.7) | 1788 (90.9) | 5411 (91.4) |
a-bThere is no difference between classes with the same letter in each row
*Chi-square test frequency (percentage)
p < 0.05
Table 4.
Comparison of fenestration presence by class within each surface and region
| Surface | Region | Fenestration | Class I(%) | Class II(%) | Class III(%) | Total | p |
|---|---|---|---|---|---|---|---|
| Buccal | 2 | yes | 16 (1.6) | 22 (2.2) | 29 (2.9) | 67 (2.2) | 0.147 |
| no | 990 (98.4) | 972 (97.8) | 979 (97.1) | 2941 (97.8) | |||
| 3 | yes | 50 (5) | 55 (5.5) | 46 (4.6) | 151 (5) | 0.614 | |
| no | 958 (95) | 941 (94.5) | 962 (95.4) | 2861 (95) | |||
| Total | yes | 66 (3.3) | 77 (3.9) | 75 (3.7) | 218 (3.6) | 0.580 | |
| no | 1948 (96.7) | 1913 (96.1) | 1941 (96.3) | 5802 (96.4) | |||
| Lingual | 2 | yes | 9 (0.9)a | 31 (3.1)b | 31 (3.1)b | 71 (2.4) | 0.001* |
| no | 999 (99.1) | 965 (96.9) | 977 (96.9) | 2941 (97.6) | |||
| 3 | yes | 20 (2) | 18 (1.8) | 25 (2.5) | 63 (2.1) | 0.551 | |
| no | 987 (98) | 978 (98.2) | 983 (97.5) | 2948 (97.9) | |||
| Total | yes | 29 (1.4)a | 49 (2.5)ab | 56 (2.8)b | 134 (2.2) | 0.011* | |
| no | 1986 (98.6) | 1943 (97.5) | 1960 (97.2) | 5889 (97.8) | |||
| Total | 2 | yes | 25 (1.2)a | 53 (2.7)b | 60 (3)b | 138 (2.3) | 0.001* |
| no | 1989 (98.8) | 1937 (97.3) | 1956 (97) | 5882 (97.7) | |||
| 3 | yes | 70 (3.5) | 73 (3.7) | 71 (3.5) | 214 (3.6) | 0.944 | |
| no | 1945 (96.5) | 1919 (96.3) | 1945 (96.5) | 5809 (96.4) | |||
| Total | yes | 95 (2.4)a | 126 (3.2)ab | 131 (3.2)b | 352 (2.9) | 0.032* | |
| no | 3934 (97.6) | 3856 (96.8) | 3901 (96.8) | 11,691 (97.1) |
a-bThere is no difference between classes with the same letter in each row
*Chi-square test
%Frequency (percentage)
p < 0.01
Discussion
The position of the incisors plays a crucial role in orthodontic treatment planning [21]. However, fixed orthodontic treatment has been reported to potentially have detrimental effects on changes in buccal bone thickness, dehiscence and fenestration [6, 14, 15, 22]. The results of the present study indicate that alveolar bone thickness did not differ significantly among skeletal Class I, II, and III malocclusions on either the buccal or lingual surfaces of the maxilla and mandible, confirming the first null hypothesis. However, while no significant differences were found on buccal and lingual surfaces when analyzed separately, the overall prevalence of dehiscence was lower in Class II compared to Class I and III, and fenestration was more frequent in Class II and III malocclusions, partially rejecting the second null hypothesis. These findings suggest that although bone thickness itself does not vary with skeletal pattern, the distribution of cortical defects may be influenced by malocclusion type.
The present study also demonstrates the topographic bone structure surrounding the roots of anterior teeth. Identifying pre-existing bone defects is essential for orthodontic treatment planning, especially in camouflage therapies, which are often challenging and must be meticulously designed. The position and inclination of the incisors play an important role in treatment planning for Class II and Class III malocclusions [23, 24]. When changes in incisor inclination are anticipated, the root should be carefully evaluated in three sections. Although Yagci et al. [14] previously evaluated dehiscence and fenestration in skeletal Class I, II, and III malocclusions, the current study provides a more comprehensive analysis by assessing both buccal and lingual bone thickness and the prevalence of cortical defects across three root regions using axial CBCT slices in a balanced sample across all skeletal patterns.
When the groups of similar studies are analyzed, the age range varies from 16 to 87 years [15, 25]. In addition to studies that found no significant difference between age groups in the presence of fenestration and dehiscence [26, 27], some studies reported that the presence of fenestration and dehiscence decreased with age. The decrease in these bone defects is because aging increases the likelihood of periodontal disease. Therefore, the structure of these bone defects changes and teeth are lost. The prevalence of dehiscence and fenestration bone defects in the remaining teeth is decreased [25, 28]. Therefore, we preferred the age range between 14 and 35 years in this study.
Technical issues also warrant discussion. CBCT voxel size is a potential limitation, as bone plates thinner than the voxel may be underestimated [29]. Although smaller voxel sizes improve resolution, they also increase radiation dose; therefore, the ALARA (As Low As Reasonably Achievable) principle must be respected [30]. Although CBCT with voxel sizes of 0.3 mm and 0.4 mm is commonly used in orthodontic diagnostics the relatively large voxel size of 0.4 mm in this study may have limited the detection of very thin cortices, particularly in the buccal and lingual regions [31]. As Molen [31] emphasized, an important factor affecting the minimum resolvable distance is the partial volume averaging effect, which may cause thin cortical bone structures to appear absent or underestimated. Therefore, the potential underestimation of alveolar bone thickness, dehiscence, and fenestration should be acknowledged as a significant limitation when interpreting the results.Wood et al. [32] demonstrated that a voxel size of 0.2 mm yielded more accurate bone thickness measurements in pig skulls with soft tissue present. In our study, a standardized voxel size (0.4 mm) and FOV were applied to all individuals, ensuring comparability among malocclusion groups, although this limitation must be acknowledged.
Recent systematic reviews have reported that orthodontic treatment can reduce alveolar bone thickness, particularly at the cervical third, depending on incisor movement [19, 22, 33]. These changes may be influenced by multiple factors such as bracket design, applied forces, and root movement mechanics [21, 22]. In their systematic review of the alveolar bone thicknesses of healthy individuals who did not undergo orthodontic treatment from different points and with different techniques, Shafizadeh et al. [15] stated that the labial alveolar bone thickness of the anterior teeth in the maxilla varied between 0.42 and 1.75 mm, and the palatal alveolar bone thickness varied between 0.97 and 8.13 mm. They observed that the lingual and labial alveolar bone thicknesses of the mandibular anterior teeth were 0.4–3.71 mm and 0.38–5.44 mm. However, when the research was analyzed, it was observed that the evaluated studies were conducted especially for surgical procedures. For this purpose, they were evaluated 5–6 mm below the alveolar bone crest or at the apical levels. At this point, we think the wide range of the observed values is due to the differences in the measurement points. In addition, 90% of the analyzed studies emphasized that the sample size corresponded to the high-risk group.
The prevalence of dehiscence and fenestration reported in the literature varies between 27.07 and 61.57% and 3.06–36.51%, respectively [6, 14, 34, 35]. These defects are reported to increase following orthodontic treatment [35–37]. When comparing across malocclusions, Evangelista et al. [12] found higher dehiscence in Class I than Class II, while Yagcı et al. [14] reported the highest rates in Class III. Similarly, Sun et al. [38] observed more dehiscence in mandibular incisors of Class III patients. Our findings align with these studies, showing that Class II subjects had fewer dehiscences, while Class III subjects tended to have higher prevalence, particularly in the mandible.
For fenestration, Evangelista et al. [12] reported a prevalence of 36.51%, most frequently in maxillary lateral incisors and canines, while Yagcı et al. [14] found fenestrations more often on buccal surfaces in Class II malocclusions. In contrast, Enhoş et al. [13] found no significant differences between vertical skeletal patterns, though buccal fenestrations were more common across all groups. Han et al. [39] and Sun et al. [6] similarly reported higher fenestration prevalence in Class III malocclusions. In our study, fenestration was significantly less frequent in Class I compared to Class II and III, especially on lingual surfaces, consistent with previous reports.
The lower prevalence of dehiscence in Class II malocclusions observed in our study may reflect differences in alveolar bone anatomy rather than incisor inclination, as the incisor positions were standardized across groups. Previous studies have reported that Class III individuals tend to exhibit thinner buccal cortical bone in the anterior mandible, which may predispose them to dehiscence [14, 37]. Class II subjects may benefit from relatively thicker alveolar housing in the anterior maxilla, offering more protection against dehiscence.
The higher prevalence of fenestration in Class II and III malocclusions may be explained by variations in root positioning within the alveolar envelope or anatomical differences in apical bone morphology. Even with standardized incisor inclinations, fenestration may occur when roots approach thin cortices, especially in the apical third. Studies such as those by Enhos et al. and Sun et al. have demonstrated that skeletal patterns can influence fenestration prevalence independently of incisor angulation [6, 13, 38].
Taken together, our results and prior findings highlight the clinical importance of cortical morphology in orthodontic planning. Even when alveolar bone thickness appears similar across skeletal classes, cortical defects such as dehiscence and fenestration may be more prevalent in certain malocclusions. This is particularly relevant in treatment planning for Class II patients requiring incisor protrusion and Class III patients requiring incisor retraction, where root movement risks cortical bone perforation. For this reason, evaluation of alveolar bone in three regions (cervical, middle, apical) may help clinicians anticipate risks associated with different types of tooth movement, including tipping and translation.
The etiology of these conditions is multifactorial, involving a combination of biological, environmental, and systemic factors. The position and morphology of teeth are significant factors, as proclined or rotated incisors are more susceptible to cortical defects. Alveolar bone thickness is also of critical importance, with thinner buccal or lingual cortices increasing susceptibility. Furthermore, the magnitude and direction of orthodontic forces can directly affect bone integrity during excessive tooth movement. Patient-related factors, including age, sex, and the presence of periodontal disease, have been associated with variations in prevalence. These considerations underscore the necessity for future studies to explore the correlations between these factors and bony defects in a more comprehensive manner.
Limitations of the present study include its retrospective design, the restriction to a single population, exclusion of malocclusions with different vertical skeletal patterns, lack of evaluation of posterior crowding, and reliance on a voxel size of 0.4 mm, which may underestimate very thin cortical plates. Another limitation of the present study is that the vertical height of the incisor tip to the palatal plane, which may influence alveolar bone thickness, could not be evaluated due to the constraints of the available retrospective data. Moreover, the relatively broad age range of the sample (14–35 years) may have introduced variability in alveolar bone morphology, as age-related changes in bone density and cortical structure are known to occur. Additionally, the inclusion of both male and female participants without stratified analysis by sex may have influenced the findings, as sex-related differences in alveolar bone characteristics have been previously reported. Nevertheless, vertical variation was partly controlled by restricting the SN–GoGn angle (31°±5°). Future multicenter, prospective studies with more diverse populations and vertical skeletal classifications are recommended to confirm these results.
Conclusion
Alveolar bone thickness on the buccal and lingual surfaces did not differ significantly among skeletal Class I, II, and III malocclusions. However, the prevalence of cortical bone defects showed variation: dehiscence was less common in Class II compared with Class I and III, while fenestration was more frequent in Class II and III than in Class I. These findings highlight that, even in the absence of thickness differences, cortical defects may be influenced by skeletal pattern. Therefore, careful assessment of alveolar morphology with CBCT should be considered in orthodontic treatment planning, particularly for camouflage strategies involving anterior tooth movement.
Authors’ contributions
Conceptualization: [Y. T]; Methodology: [M. T, S. K]; Investigation: [Y. T, S.B]; Formal analysis: [S. K]; Writing—original draft preparation: [M. T, Y.T]; Writing—review and editing: [S.K, M. T]; Resources: [S.K, S.B]; Supervision: [S. K, M. T].
Funding
This study was not financially supported.
Data availability
The datasets used and/or analysed during the current study available from the corresponding author on reasonable request.
Declarations
Ethics approval and consent to participate
Van Yuzuncu Yıl University Faculty of Non-Interventional Clinical Research Ethics Committee provided its approval to this study. This retrospective research was conducted in accordance with the principles of the Declaration of Helsinki and informed approval was obtained from those included in the study. (permission date/number: 2022/12 − 02).
Consent for publication
Not applicable.
Competing interests
The authors declare no competing interests.
Footnotes
Publisher’s Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
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Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Data Availability Statement
The datasets used and/or analysed during the current study available from the corresponding author on reasonable request.