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Article

An Evaluation of the Ramus Mandibular Asymmetry on the Panoramic Radiography

by
Andreea Raluca Hlatcu
1,
Elena Galan
2,*,
Ștefan Milicescu, Jr.
3,
Elina Teodorescu
1 and
Ecaterina Ionescu
1
1
Department of Orthodontics and Dentofacial Orthopedics, Faculty of Dental Medicine, Carol Davila University of Medicine and Pharmacy, 050474 Bucharest, Romania
2
Independent Researcher, 020034 Bucharest, Romania
3
Department of Dental Aesthetics, Faculty of Dental Medicine, Carol Davila University of Medicine and Pharmacy, 050474 Bucharest, Romania
*
Author to whom correspondence should be addressed.
Appl. Sci. 2023, 13(13), 7645; https://doi.org/10.3390/app13137645
Submission received: 14 May 2023 / Revised: 11 June 2023 / Accepted: 27 June 2023 / Published: 28 June 2023
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Abstract

:
This study is intended to focus on the evaluation of posterior vertical mandibular asymmetry by calculating the mandibular asymmetry index on the panoramic radiography in different types of malocclusions, considering the sexual dimorphism in children and adolescent patients and performing a comparative analysis between these groups. In this context, a cross-sectional study was conducted for a group of 214 patients (134 females and 80 males with a mean age of 9.5 ± 2 years). The asymmetry index was calculated for each patient according to the Habets method. The results were analyzed by using the independent Student t-test, ANOVA and Mann–Whitney U-test at the 95% confidence level (p < 0.05). The results of the analyses showed a statistically significant difference between males and females at the level of the condylar index (p = 0.023) and a significant difference in the unilateral posterior crossbite in the Mann–Whitney U test (p = 0.01). No statistically significant differences were found between males and females in the index of the mandibular ramus and condyle-plus-ramus. The highest value of the asymmetry index was recorded at the level of the condyle. We found higher values of asymmetry in Angle Class I malocclusions in all groups and in Class II/1 in the group of females.

1. Introduction

Mandibular asymmetry is an important factor in facial aesthetics, at the same time playing an essential role in the functionality of the maxillofacial apparatus [1,2]. Multiple factors, such as age, gender, skeletal growth patterns, changes in dental occlusion, and muscle activity, can impact the development of mandibular asymmetry [3,4,5,6,7]. Of all craniofacial asymmetries, mandibular asymmetries pose a special interest due to their high frequency [8,9].
Studies have shown that the inferior third of the face is more prone to facial asymmetries, the maxillary growth being stable due to the connection with the synchondroses of the cranial base, thus being less vulnerable to the influence of environmental factors. In a different way, the mandible is more sensitive to environmental factors being the only mobile bone of the skull [10,11]. It provides support for the soft tissues so that the slightest change in shape or position impacts the facial appearance [12].
Usually, the elective investigations used in order to identify and diagnose facial asymmetries are panoramic radiography, posteroanterior cephalometric radiography and Cone Beam Computed Tomography (CBCT). Panoramic radiographs are routinely acquired during pediatric dentistry and orthodontic treatments as part of the initial orthodontic records. It is a simple and easy X-ray with a relatively low level of irradiation compared to that of Cone Beam Computed Tomography (CBCT), providing important information on the patient’s dentition [13,14]. Although the CBCT remains the golden standard imagistic technique [15,16,17] and it is considered the most appropriate imaging method for the evaluation of bone structures, the high level of radiation poses a potential risk, especially for children [18,19,20].
The use of panoramic radiographs to evaluate side-to-side differences is equivocal, as it has been shown that there is magnification in both vertical and horizontal planes. To prevent magnification in the vertical direction, the distance between the focal point of the X-ray tube and the film must always be the same [21,22]. Despite the fact that panoramic radiography has low resolution and is affected by magnification, image distortion, and the superposition of different anatomic structures, in many studies on facial asymmetry, condylar or ramal asymmetry is determined using panoramic radiography [23,24,25,26,27,28,29,30]. These studies have assessed the reliability and validity of panoramic radiographs for measuring condylar and ramal asymmetry. We have to take into account that the vertical component of the structures that appear on the panoramic radiographs is less subject to distortion due to their posterior positioning compared to the anterior ones. Some authors have suggested that good-quality panoramic radiographs yield acceptable results with acceptable reproducibility, are non-invasive and have a favorable cost–benefit relationship [17,31,32,33,34,35,36,37,38,39].
In order to assess validity, Habets concluded that the patient’s head must be centered in the head holder when a clinical panoramic radiography is to be evaluated, and they were the first researcher to suggest using an asymmetry index, comparing vertical differences between the left and right condyles and rami. By changing the position of the mandible horizontally 10 mm or less, the vertical difference can be changed to less than 6%. They deemed asymmetry as being relevant when the asymmetry index was higher than 3%, which was accompanied by a difference of 6% between vertical mandibular condyles and rami, thus pointing to genuine vertical asymmetry. Habets only provides an index that helps observe the differences in height between the left and right condyle [31,32].
In the horizontal plane, the distortion between the left and right sides depends on the position of the patient’s head, and it was suggested that the mesiodistal widths of the mandibular first molars should be bilaterally compared to evaluate horizontal distortions in panoramic radiographs [34].
The early diagnosis of mandibular asymmetry is essential for preventing and intercepting asymmetry and choosing efficient therapeutic actions so as to avert its consequences [40,41].
A cross-sectional study was conducted on a group of 214 subjects (134 females and 80 males) with an age range of 7–15 years. The evaluation of mandibular posterior vertical asymmetry was performed using panoramic radiography for the subjects in the studied group. The asymmetry indexes were calculated according to the method of Habets. Later, the percentage of asymmetry was calculated for the condyle (CAI), ramus (RAI) and condyle-plus-ramus (MAI) in different types of malocclusions (Angle Cl I, Cl II/1, Cl II/2, Cl III and UPC), taking into account the sexual dimorphism. Early asymmetries of the condyle were observed in both genders. The obtained results showed us that this method could easily be used clinically, providing information about the mandibular asymmetry stage of each patient before the start of orthodontic treatment.

2. Materials and Methods

The study group was selected from the population of Bucharest and its surrounding areas, consisting of 214 patients (134 females and 80 males; age range: 7–15 years) with malocclusions who need orthodontic treatment.
The patients included in the study were divided into five groups of malocclusions: four groups according to Angle classification: Class I, Class II/1, II/2 and Class III, to which was added the fifth group, patients with unilateral posterior crossbite (UPC), a category in which patients who had at least one pair of teeth with posterior crossbite, were included. The groups were organized as follows: 21 subjects, Class I (9.8%); 56 subjects, Class II/1 (26.2%); 55 subjects, Class II/2 (25.7%); 35 subjects, Class III (16.4%); and 47 subjects with unilateral posterior crossbite UPC (22%). The criteria for inclusion in the study group allowed for the participation of patients who presented with first molar teeth on the mandibular arch, aged between 7 and 15 years of both genders and with no history of orthodontic treatments. Patients whose panoramic radiographs had poor resolution or had horizontal distortions, patients who showed signs of craniofacial syndromes or malformations and major temporomandibular joint disorders were excluded from the study group. For each patient, before beginning orthodontic treatment, the initial panoramic radiography was analyzed for diagnostic purposes. Informed consent was obtained from the relatives of all patients before the start of the study. Ethical approval was given by the Research Ethics Committee.
In this study, the panoramic radiographs were made in the same center, using the same Planmeca ProMax panoramic device (Planmeca Oy, 00880 Helsinki, Finland), in accordance with the manufacturer’s instructions (66 kVp, 7 mA, and 16 s), in a standard manner. The X-rays were taken with the patient’s incisors in an edge-to-edge relationship in a pipe.
Pre-orthodontic treatment panoramic radiographs were checked for imaging quality, the visibility of mandibular condyles, and the absence of radiographical artifacts projecting over the mandibular structures.
The evaluation was conducted in a dimly lit room with tonal adjustments made to the images to improve the view, as conducted by a single investigator. The panoramic X-rays were traced manually using acetate paper and a hard lead pencil (2H) on an X-ray view box (Huion®). A maximum number of 10 random radiographs were analyzed during each working session in order to prevent investigator fatigue.
The maximum mesiodistal widths of the mandibular first molar teeth were assessed bilaterally to detect horizontal distortion. To avoid it, panoramic radiographs with mesiodistal size differences greater than 1 mm between the right and left mandibular first molars were excluded from the study.
On the panoramic radiography, the vertical parameters of condyle height (CH), ramus height (RH), and total height (CH+RH) were measured on the right and left side, and the indices of mandibular asymmetry were calculated according to the Habets et al. method, as shown in Figure 1.
The points and lines on the panoramic radiography for calculating the asymmetry index were as follows:
  • O1: the most lateral point of the condyle on the panoramic radiography;
  • O2: the most lateral point of the ascending ramus on the panoramic radiography;
  • A line: the line tangent to the mandibular ramus, drawn between point O1 and point O2;
  • B line: line perpendicular to line A passing through the most superior point of the condyle on the panoramic radiography.
The following mandibular vertical measurements were carried out:
  • CH: the condyle height, represents the distance between point O1 and the intersection point of A and B lines;
  • RH: the ramus height, represents the distance between O1 and O2;
  • CH+RH: represents the total height of the condyle-plus-ramus, the distance between point O2 and the intersection point of the A and B lines.
The asymmetry index was calculated using the Habets formula:
Condylar Asymmetry Index (%)
(CAI) = │(CH right—CH left)/(CH right + CH left)│ × 100.
Ramus Asymmetry Index (%)
(RAI) = │(RH right—RH left)/(RH right + RH left)│ × 100.
Mandibular Asymmetry Index (%)
(MAI) = │[(CH+RH right)] − [(CH+RH left)]/[(CH+RH right) + (CH+RH left)]│× 100.
The orthodontic diagnosis was confirmed via orthodontic records analysis and study cast for each included subject.
In order to calculate intra-observer reliability, after 4 weeks, the same investigator repeated measurements of all panoramic radiographs included in the study.
The statistical analyses used in this study were performed using SPSS software (Statistical Package for Social Sciences for Windows, version 23.0, SPSS Inc, Chicago, IL, USA).
To interpret the data obtained, the following statistical analyses were performed:
-
Independent samples Student’s t-test was used to analyze the difference between linear measurement mean for the asymmetry index between male and female and for the data with a normal distribution;
-
The ANOVA test was used to analyze independently the differences between the evaluated groups’ recorded data;
-
The Mann–Whitney U test was used for the distribution of data differences recorded between groups;
The statistical analyses had a reliability level of over 95% (p < 0.05).

3. Results

Upon repeating the independent t-test between the first and the second measurement, the inter-class correlation coefficient was found to be greater than 0.95 for all parameters. The Lin coefficient showed a high correlation between the two measurements, taken at one month-intervals (rc = 0.87 condyle, rc = 0.94 ramus, rc = 0.94 condyle-plus -ramus), results which allowed for the use of these data in the main study.
Taking into account sexual dimorphism, the main study group was divided into: male and female, and according to occlusion type, it was divided into five subgroups: 21 subjects were in Class I (thirteen females and eight males), 56 subjects were in Class II/1 (35 females and 21 males), 55 subjects were in Class II/2 (36 females and 19 males), 35 subjects were in Class III (23 females and 12 males) and 47 subjects were classed as having unilateral posterior crossbite (27 females and 20 males) (Figure 2).
Condylar asymmetry (CAI), ramus asymmetry (RAI) and condyle-plus-ramus asymmetry (MAI) indexes for the females and males within the study group were calculated, and the results are recorded in Table 1.
The condylar asymmetry indexes (CAI) had a value higher than 3%, which indicates the presence of asymmetry at the condyle level. The mean value was higher for males (11.2%) than for females (9.3%), with a statistically significant difference, with the p-value being 0.023. The ramus asymmetry index (RAI) was lower than 3%, with the mean value of the index being higher for males (2.7%) than females (2.4%) but without any statistically significant differences. Condyle-plus-ramus asymmetry index (MAI) had the lowest asymmetry percentage, with the mean values being higher for females (2.4%) than males (2.1%) without any statistically significant differences.
Condylar asymmetry index (CAI) was evaluated according to types of occlusions, and it was analyzed to see if there are differences between females and males. In all classes, the index was higher than 3% and varied between 8.2 and 10.7% for females and 9.3 and 15.3% for males (Table 2).
In all malocclusions studied, (CAI) condylar asymmetry index values were higher for males than females, and within the male study group, the highest value of asymmetry was found in Class I, followed the decreasing order of unilateral posterior crossbite (UPC), Angle Class II/1, III and II/2. For females, the higher value of asymmetry was recorded in Angle Class II/1, which was followed in decreasing order by Class I, unilateral posterior crossbite, Class II/2 and III. In the unilateral posterior crossbite taken from the Mann–Whitney U test, a significant difference was noticed between males and females, with the p-value being 0.01.
The analysis of the ramus asymmetry index (RAI) according to different occlusion types revealed values equal to 3% (in Angle Class I and in unilateral posterior crossbite UPC for males and Angle Class III for females) or below 3%, with the mean values being higher for males than females, except for Angle Class III, where the mean values for females were higher (Table 3).
From the Mann–Whitney U test in Angle Class III malocclusions, the highest difference between females and males was observed between females (3.0%) and males (2.4%), with the p-value being 0.15 and without any significant differences.
The condyle-plus-ramus asymmetry index (MAI) was generally lower than 3%, with values of 3% being recorded only within the female study group with Angle Class III malocclusion. The asymmetry recorded in all classes of malocclusions was in the group of females compared to the group of males, except for Angle Class II/1, where it was greater for males. The highest asymmetry of condyle-plus-ramus was recorded in Angle Class III malocclusion (females 3% and males 2.4%), and the most significant difference was recorded for the Mann–Whitney U test, with the p-value being 0.19 but without any statistically significant differences (Table 4).

4. Discussion

In order to evaluate mandibular posterior vertical asymmetry, the analysis of the panoramic radiography proved to be an efficient conventional method for the radiological film capturing temporomandibular joints, the ramus of the mandible, the body of the mandible and dental structures [42]. Although its reliability and validity are still in question due to the magnifying distortion effect, most authors have demonstrated that changes in the head position do not significantly affect the results of the vertical measurements [31,32,43]. It is considered that the asymmetry caused by the incorrect head position has a value below 6%, and a difference in growth recorded between the condyle and the right and left ramus higher than 6% already indicates the presence of vertical mandibular asymmetry [31,32].
In the specialized literature, in some studies of mandibular asymmetry, sexual dimorphism was not taken into account due to the limited size of the studied groups [44,45], and in other studies, these differences were investigated, but no statistically significant results were recorded [37,46,47,48].
This study aimed to evaluate the asymmetry of the mandibular vertical ramus in two groups of patients, females and males, with mixed and permanent dentition with different types of malocclusions in the sagittal and transverse planes. From the collected results, in the group of 214 patients, a percentage higher than 3% of condyle asymmetry was observed, with the percentage of males being higher than that of females, and with statistically significant differences. In the types of malocclusions studied, the greatest changes were highlighted when calculating the asymmetry index of the condyle in the unilateral posterior crossbite, which was higher in males than in females, with a statistically significant difference. Regarding the asymmetry indices of the ramus and the condyle-plus-ramus, homogeneity was recorded within the studied groups, with no notable differences between the group of females and males. In females, greater asymmetry of the condyle could be appreciated in Angle Class II/1 and of the ramus and condyle-plus-ramus in Angle Class III. In males, the percentage of asymmetry in the condyle was more noticeable in Class Angle I, of the ramus in Class I and unilateral posterior crossbite, and of the condyle-plus-ramus in Angle Class III.
Kurt et al. evaluated the condylar and mandibular ramus asymmetry for a group of patients (mean age 14.53 years) with Angle Class I and II malocclusions in order to identify possible differences between males and females. They did not record any differences for any of the asymmetry indices, and they found the value of the condylar asymmetry index in the group with Angle Class I malocclusion in a percentage of 7.57%. Unlike the aforementioned study, we found notable differences between the two genders, and for the condylar asymmetry index, we found values of 15.3% in Angle Class I malocclusion in males and 10.5% in females [35].
Kilic et al. evaluated mandibular asymmetry in adolescent patients with unilateral posterior crossbite (UPC) and patients with normal occlusion (control group). Regarding the condylar asymmetry index (CAI), they found a significantly higher value in patients with unilateral posterior crossbite compared to the control group. Our study was carried out using children and included malocclusions in the transverse plane and malocclusions in the sagittal plane. Similar to the cited study, the condylar asymmetry index was determined with a high value in unilateral posterior crossbite but with a value different from the cited study; it had the highest value in Angle Class I malocclusions, and for the group of females, increased values of CAI were also recorded in Angle Class II/I, with condylar asymmetry in UPC having only the third place in terms of frequency in the group of females and the second position in the group of males [38].
Similar to Kilic’s study, Tortarolo et al. observed a condylar asymmetry index (CAI) in children with a high value in unilateral reverse occlusion, but these studies only investigated unilateral posterior crossbite compared to the control group with normal occlusion [49]. The novelty of our study comes from the fact that classification was made by classes of malocclusions, including in the study, in addition to UPC, the malocclusions from Angle’s classification: Class I, Class II/1, Class II/2 and Class III. It is surprising that we would have expected the greatest asymmetry of the condyle to appear in the UPC (in our study, 11.8% males and 8.7% females), and despite this, we found higher values of asymmetry in Angle Class I malocclusions in all groups (15.3% males and 10.5% females), and in Class II/1 in the group of females (10.7%).
Sezgin et al. evaluated the association between different types of occlusions and mandibular asymmetry in young patients between 11 and 15 years. They calculated the asymmetry indexes using panoramic radiography in four groups of patients with Angle Class I, II/1, II/2, and III malocclusions and a control group (with neutral occlusion), and they did not notice any statistically significant differences between male and female patients [48]. The results of the research confirm Sezgin’s study regarding the aforementioned classes of malocclusions, but an additional new type of occlusions was introduced, unilateral posterior crossbite, a type within which statistically significant differences were recorded at the level of the condylar index of asymmetry in the female and male study groups.
In another study, Kasimoglu et al. [37] investigated vertical asymmetries of the mandibular condyle in adolescent patients (11–16 years) with Angle Class I, Class II, Class III malocclusions, and unilateral posterior crossbite. They observed in all occlusions groups values of condylar asymmetry index higher than 3%, with patients with a unilateral posterior crossbite being the most asymmetric. Regarding gender, the authors observed statistically significant differences in the group with a unilateral posterior crossbite. They observed no statistically significant differences in the condylar asymmetry index between males and females in Angle Class I, II and III malocclusions. In the present study, although the age mean was different, similar results were observed as to those produced by Kasimoglu et al., with the condylar asymmetry index recording values of over 3%, and in unilateral posterior crossbite, statistically significant differences were observed between the group of females and males.
The results of this study show us that there was a slight asymmetry of the mandibular vertical ramus since the growth period, which, if noticed in time, can be corrected through an orthodontic treatment, thus avoiding it worsening in the future.
The limitations of the study come from the lack of homogeneity of the sample regarding the number of participants per age and gender groups and the fact that the results were obtained from a cross-sectional study, which presents a snapshot, a momentary image captured at a particular time.

5. Conclusions

The conclusions of the study showed that:
  • The results of the study showed the presence of significant asymmetry at the condylar level, obtaining values of over 3% for CAI and non-significant asymmetry (values of less than 3% for RAI and MAI) in the case of vertical ramus.
  • Regarding sexual dimorphism, there are significant differences in condylar asymmetry index (CAI) between females and males, which are in favor of males. These differences are not statistically significant for the ramus asymmetry index (RAI) and the mandibular asymmetry index (MAI).
  • We would have expected the greatest asymmetry in the condyle to appear in the UPC, and despite this, we found higher values of asymmetry in Angle Class I malocclusions in all groups (15.3% males and 10.5% females) and Class II/1 in the group of females (10.7%).
  • It was observed that in unilateral posterior crossbite, UPC, asymmetry was recorded at the condylar level in the case of both genders, also recording notable differences between females and males, but the values obtained are lower than the asymmetry observed in Angle Class I malocclusions and in Class II/1 in the female group.
  • In Angle Class II/2 malocclusion, the smallest asymmetry was recorded at the posterior part of the mandibular vertical ramus.
  • The study carried out was performed on growing patients aged between 7 and 15 years. The presence of an increased condylar asymmetry index is a sign of altered skeletal growth and should be considered in the diagnostic process and treatment plan. Because of the high prevalence of condylar asymmetry in unilateral posterior crossbite, the orthodontic treatment should be accomplished early, and the advantage of Habets method is that it uses routinely acquired panoramic radiographs and does not require additional exposure to ionizing radiation, which makes it very suitable for younger patients.

Author Contributions

Conceptualization, A.R.H. and E.G.; methodology, E.I. and E.T.; software, A.R.H. and E.G.; validation, E.I., E.T. and Ș.M.J.; formal analysis, A.R.H. and E.G.; investigation, A.R.H. and E.G.; resources, E.G. and E.T.; data curation, A.R.H., E.G. and E.I.; writing—original draft preparation, A.R.H., writing, review and editing, E.G. and E.I.; visualization, A.R.H. and E.G., supervision, E.I.; project administration A.R.H., Ș.M.J. and E.I. All authors have read and agreed to the published version of the manuscript.

Funding

No external funds were received for this research.

Institutional Review Board Statement

This study was conducted in accordance with the Declaration of Helsinki and approved by the ethics committee of the respective institution (“Carol Davila” University of Medicine and Pharmacy [protocol code PO-35-F-03, 28 March 2022]).

Informed Consent Statement

Informed consent was obtained from all subjects involved in this study.

Conflicts of Interest

The authors declare no conflict of interest.

References

  1. Peck, S.; Peck, L.; Kataja, M. Skeletal asymmetry in esthetically pleasing faces. Angle Orthod. 1991, 61, 43–48. [Google Scholar] [PubMed]
  2. Sperber, G.H. Craniofacial Development; B.C. Decker: Hamilton, ON, Canada, 2001; pp. 127–136. [Google Scholar]
  3. Melnik, A.K. A cephalometric study of mandibular asymmetry in a longitudinally followed sample of growing children. Am. J. Orthod. Dentofac. Orthop. 1992, 101, 355–366. [Google Scholar] [CrossRef] [PubMed]
  4. Moyers, R.E. Handbook of Orthodontics for the Student and General Practitioner; Year Book Medical Publishers: Chicago, IL, USA, 1973. [Google Scholar]
  5. Moorrees, C.F.; Gron, A.M. Principles of orthodontic diagnosis. Angle Orthod. 1966, 36, 258–262. [Google Scholar]
  6. Saccucci, M.; D’Attilio, M.; Rodolfino, D.; Festa, F.; Polimeni, A.; Tecco, S. Condylar volume and condylar area in class I, class II and class III young adult subjects. Head Face Med. 2012, 8, 34. [Google Scholar] [CrossRef] [PubMed]
  7. Ueki, K.; Nakagawa, K.; Marukawa, K.; Takatsuka, S.; Yamamoto, E. The relationship between temporomandibular joint disc morphology and stress angulation in skeletal Class III patients. Eur. J. Orthod. 2005, 27, 501–506. [Google Scholar] [CrossRef]
  8. Björk, A. Variations in the growth pattern of the human mandible: Longitudinal radiographic study by the implant method. J. Dent. Res. 1963, 42, 400–411. [Google Scholar] [CrossRef] [PubMed]
  9. Ricketts, R.M. A principle of arcial growth of the mandible. Angle Orthod. 1972, 42, 368–386. [Google Scholar]
  10. Haraguchi, S.; Iguchi, Y.; Takada, K. Asymmetry of the face in orthodontic patients. Angle Orthod. 2008, 78, 421–426. [Google Scholar] [CrossRef]
  11. Macrì, M.; Festa, F. Three-dimensional evaluation using CBCT of the mandibular asymmetry and the compensation mechanism in a growing patient: A case report. Front. Public Health 2022, 10, 921413. [Google Scholar] [CrossRef]
  12. Cheong, Y.W.; Lo, L.J. Facial asymmetry: Etiology, evaluation, and management. Chang Gung Med. J. 2011, 34, 341–351. [Google Scholar]
  13. Damstra, J.; Fourie, Z.; Ren, Y. Evaluation and comparison of postero-anterior cephalograms and cone-beam computed tomography images for the detection of mandibular asymmetry. Eur. J. Orthod. 2013, 35, 45–50. [Google Scholar] [CrossRef] [PubMed]
  14. Lewis, E.L.; Dolwick, M.F.; Abramowicz, S.; Reeder, S.L. Contemporary imaging of the temporomandibular joint. Dent. Clin. N. Am. 2008, 52, 875–890. [Google Scholar] [CrossRef]
  15. Van Elslande, D.C.; Russett, S.J.; Major, P.W.; Flores-Mir, C. Mandibular asymmetry diagnosis with panoramic imaging. Am. J. Orthod. Dentofac. Orthop. 2008, 134, 183–192. [Google Scholar] [CrossRef] [PubMed]
  16. Feragalli, B.; Rampado, O.; Abate, C.; Macrì, M.; Festa, F.; Stromei, F. Cone beam computed tomography for dental and maxillofacial imaging: Technique improvement and low-dose protocols. Radiol. Med. 2017, 122, 581–588. [Google Scholar] [CrossRef]
  17. Lim, Y.S.; Chung, D.H.; Lee, J.W.; Lee, S.M. Reliability and validity of mandibular posterior vertical asymmetry index in panoramic radiography compared with cone-beam computed tomography. Am. J. Orthod. Dentofac. Orthop. 2018, 153, 558–567. [Google Scholar] [CrossRef]
  18. Brooks, S.L.; Brand, J.W.; Gibbs, S.J.; Hollender, L.; Lurie, A.G.; Omnell, K.A.; Westesson, P.L.; White, S.C. Imaging of the temporomandibular joint: A position paper of the American Academy of Oral and Maxillofacial Radiology. Oral Surg. Oral Med. Oral Pathol. Oral Radiol. Endod. 1997, 83, 609–618. [Google Scholar] [CrossRef] [PubMed]
  19. Kokich, V.G. Cone beam computed tomography: Have we identified the orthodontic benefits? Am. J. Orthod. Dentofac. Orthop. 2010, 137 (Suppl. S4), S16. [Google Scholar] [CrossRef]
  20. Roberts, J.A.; Drage, N.A.; Davies, J.; Thomas, D.W. Effective dose from cone beam CT examinations in dentistry. Br. J. Radiol. 2009, 82, 35–40. [Google Scholar] [CrossRef]
  21. Manson-Hing, L.R.; Lund, T.M. A study of the focal troughs of three panoramic dental x-ray machines. Part II. Image dimensions. Oral Surg. Oral Med. Oral Pathol. 1975, 39, 647–653. [Google Scholar]
  22. Lund, T.M.; Manson-Hing, L.R. A study of the focal troughs of three panoramic dental x-ray machines. Part I. The area of sharpness. Oral Surg. Oral Med. Oral Pathol. 1975, 39, 318–328. [Google Scholar] [CrossRef]
  23. Rondon, R.H.; Pereira, Y.C.; do Nascimento, G.C. Common positioning errors in panoramic radiography: A review. Imaging Sci. Dent. 2014, 44, 1–6. [Google Scholar] [CrossRef] [PubMed]
  24. Friedland, B. Clinical radiological issues in orthodontic practice. Semin. Orthod. 1998, 4, 64–78. [Google Scholar] [CrossRef]
  25. Yeo, D.K.; Freer, T.J.; Brockhurst, P.J. Distortions in panoramic radiographs. Aust. Orthod. J. 2002, 18, 92–98. [Google Scholar] [PubMed]
  26. Tronje, G.; Welander, U.; McDavid, W.D.; Morris, C.R. Image distortion in rotational panoramic radiography. I. General considerations. Acta Radiol. Diagn. 1981, 22, 295–299. [Google Scholar] [CrossRef] [PubMed]
  27. Tronje, G.; Welander, U.; McDavid, W.D.; Morris, C.R. Image distortion in rotational panoramic radiography. IV. Object morphology; outer contours. Acta Radiol. Diagn. 1981, 22, 689–696. [Google Scholar] [CrossRef]
  28. Tronje, G.; Welander, U.; McDavid, W.D.; Morris, C.R. Image distortion in rotational panoramic radiography. III. Inclined objects. Acta Radiol. Diagn. 1981, 22, 585–592. [Google Scholar] [CrossRef]
  29. Tronje, G.; Eliasson, S.; Julin, P.; Welander, U. Image distortion in rotational panoramic radiography. II. Vertical distances. Acta Radiol. Diagn. 1981, 22, 449–455. [Google Scholar] [CrossRef]
  30. Laster, W.S.; Ludlow, J.B.; Bailey, L.J.; Hershey, H.G. Accuracy of measurements of mandibular anatomy and prediction of asymmetry in panoramic radiographic images. Dentomaxillofac. Radiol. 2005, 34, 343–349. [Google Scholar] [CrossRef]
  31. Habets, L.L.; Bezuur, J.N.; van Ooij, C.P.; Hansson, T.L. The orthopantomogram, an aid in diagnosis of temporomandibular joint problems. I. The factor of vertical magnification. J. Oral Rehabil. 1987, 14, 475–480. [Google Scholar] [CrossRef]
  32. Habets, L.L.; Bezuur, J.N.; Naeiji, M.; Hansson, T.L. The orthopantomogram, an aid in diagnosis of temporomandibular joint problems. II. the vertical symmetry. J. Oral Rehabil. 1988, 15, 465–471. [Google Scholar] [CrossRef]
  33. Kambylafkas, P.; Murdock, E.; Gilda, E.; Tallents, R.H.; Kyrkanides, S. Validity of panoramic radiographs for measuring mandibular asymmetry. Angle Orthod. 2006, 76, 388–393. [Google Scholar]
  34. Uysal, T.; Sisman, Y.; Kurt, G.; Ramoglu, S.I. Condylar and ramal vertical asymmetry in unilateral and bilateral posterior crossbite patients and a normal occlusion sample. Am. J. Orthod. Dentofac. Orthop. 2009, 136, 37–43. [Google Scholar] [CrossRef] [PubMed]
  35. Kurt, G.; Uysal, T.; Sisman, Y.; Ramoglu, S.I. Mandibular asymmetry in Class II subdivision malocclusion. Angle Orthod. 2008, 78, 32–37. [Google Scholar] [CrossRef] [PubMed]
  36. Ferro, F.; Spinella, P.; Lama, N. Transverse maxillary arch form and mandibular asymmetry in patients with posterior unilateral crossbite. Am. J. Orthod. Dentofac. Orthop. 2011, 140, 828–838. [Google Scholar] [CrossRef]
  37. Kasimoglu, Y.; Tuna, E.B.; Rahimi, B.; Marsan, G.; Gencay, K. Condylar asymmetry in different occlusion types. Cranio 2015, 33, 10–14. [Google Scholar] [CrossRef] [PubMed]
  38. Kilic, N.; Kiki, A.; Oktay, H. Condylar asymmetry in unilateral posterior crossbite patients. Am. J. Orthod. Dentofac. Orthop. 2008, 133, 382–387. [Google Scholar] [CrossRef]
  39. Piancino, M.G.; Cannavale, R.; Dalmasso, P.; Tonni, I.; Filipello, F.; Perillo, L.; Cattalini, M.; Meini, A. Condylar asymmetry in patients with juvenile idiopathic arthritis: Could it be a sign of a possible temporomandibular joints involvement? Semin. Arthritis Rheum. 2015, 45, 208–213. [Google Scholar] [CrossRef]
  40. Chia, M.S.Y.; Naini, F.B.; Gill, D.S. The aetiology, diagnosis and management of mandibular asymmetry. Ortho. Update 2008, 1, 44–52. [Google Scholar] [CrossRef]
  41. Persson, M. Mandibular asymmetry of hereditary origin. Am. J. Orthod. 1973, 63, 1–11. [Google Scholar] [CrossRef]
  42. Langland, O.E.; Sippy, F.H. Anatomic structures as visualized on the orthopantomogram. Oral Surg. Oral Med. Oral Pathol. 1968, 26, 475–784. [Google Scholar] [CrossRef]
  43. Sadat-Khonsari, R.; Fenske, C.; Behfar, L.; Bauss, O. Panoramic radiography: Effects of head alignment on the vertical dimension of the mandibular ramus and condyle region. Eur. J. Orthod. 2012, 34, 164–169. [Google Scholar] [CrossRef] [PubMed]
  44. Tadej, G.; Engstrom, C.; Borrman, H.; Christiansen, E.L. Mandibular condyle morphology in relation to malocclusions in children. Angle Orthod. 1989, 59, 187–194. [Google Scholar] [PubMed]
  45. Al Taki, A.; Ahmed, M.H.; Ghani, H.A.; Al Kaddah, F. Impact of different malocclusion types on the vertical mandibular asymmetry in young adult sample. Eur. J. Dent. 2015, 9, 373–377. [Google Scholar] [CrossRef] [PubMed]
  46. Saglam, A.M. The condylar asymmetry measurements in diferent skeletal patterns. J. Oral Rehabil. 2003, 30, 738–742. [Google Scholar] [CrossRef] [PubMed]
  47. Kiki, A.; Kılıc¸, N.; Oktay, H. Condylar asymmetry in bilateral posterior crossbite patients. Angle Orhod. 2007, 77, 77–81. [Google Scholar] [CrossRef]
  48. Sezgin, O.S.; Celenk, P.; Arici, S. Mandibular asymmetry in different occlusion patterns. Angle Orthod. 2007, 77, 803–807. [Google Scholar] [CrossRef] [PubMed]
  49. Tortarolo, A.; Rotolo, R.; Nucci, L.; Tepedino, M.; Crincoli, V.; Piancino, M.G. Condylar Asymmetry in Children with Unilateral Posterior Crossbite Malocclusion: A Comparative Cross-Sectional Study. Children 2022, 9, 1772. [Google Scholar] [CrossRef]
Applsci 13 07645 g001 550
Figure 1. Linear measurements according to the Habets et al. method [32]. O1 și O2 the most lateral points corresponding to the vertical ramus; A line, tangent to the vertical ramus; B line, from the most superior point of the condyle perpendicular to the A line; CH: condyle height; RH: ramus height; CH+RH: total height of mandibular vertical ramus.
Figure 1. Linear measurements according to the Habets et al. method [32]. O1 și O2 the most lateral points corresponding to the vertical ramus; A line, tangent to the vertical ramus; B line, from the most superior point of the condyle perpendicular to the A line; CH: condyle height; RH: ramus height; CH+RH: total height of mandibular vertical ramus.
Applsci 13 07645 g001
Applsci 13 07645 g002 550
Figure 2. Total and gender percentage distribution according to the type of occlusions. In the figure on the left side, it can be seen that of the total number of 214 subjects, 9.8% are Angle Class I, 26.2% are Angle Class II/1, 25.7% are Angle Class II/2, 16.4% are Angle Class III and 22% are UPC. In the figure on the right side, it can be seen that in Angle Class I, the percentage of females is 6.1% and that of males is 3.7%; in Angle Class II/1, the percentage of females is 16.4%, and that of males is 9.8%; in Angle Class II/2, the percentage of females is 16.8% and that of males is 8.9%, in Angle Class III, the percentage of females is 10.7% and that of males is 5.6%; in UPC, the percentage of females is 12.6%, and that of males is 9%.
Figure 2. Total and gender percentage distribution according to the type of occlusions. In the figure on the left side, it can be seen that of the total number of 214 subjects, 9.8% are Angle Class I, 26.2% are Angle Class II/1, 25.7% are Angle Class II/2, 16.4% are Angle Class III and 22% are UPC. In the figure on the right side, it can be seen that in Angle Class I, the percentage of females is 6.1% and that of males is 3.7%; in Angle Class II/1, the percentage of females is 16.4%, and that of males is 9.8%; in Angle Class II/2, the percentage of females is 16.8% and that of males is 8.9%, in Angle Class III, the percentage of females is 10.7% and that of males is 5.6%; in UPC, the percentage of females is 12.6%, and that of males is 9%.
Applsci 13 07645 g002
Table
Table 1. Asymmetry indexes of vertical parameters according to sexual dimorphism.
Table 1. Asymmetry indexes of vertical parameters according to sexual dimorphism.
ParameterGenderNumber of Subjects (N)Mean (%)Standard Deviation SD (%)Min (%)Max (%)p-Value
Condylar asymmetry index (CAI)Female1349.35.40.027.30.023 *
Male8011.26.13.427.3
Ramus asymmetry index (RAI)Female1342.41.70.08.60.248
Male802.72.10.08.6
Condyle-plus-ramus asymmetry index (MAI)Female1342.31.60.09.10.554
Male802.11.70.06.6
Table
Table 2. Condylar asymmetry index (CAI) according to gender and different occlusion types.
Table 2. Condylar asymmetry index (CAI) according to gender and different occlusion types.
Type of OcclusionMaleFemalep-ValueMann-Whitney U Test
Mean (%)SD (%)Mean (%)SD (%)
I15.38.110.54.80.15660.140253
II/111.06.810.76.60.85970.792532
II/29.35.68.75.10.71530.676562
III10.95.78.24.90.18160.195488
UPC11.84.88.74.60.0323 *0.018936 *
Table
Table 3. Ramus asymmetry index (RAI) according to gender and different occlusion types.
Table 3. Ramus asymmetry index (RAI) according to gender and different occlusion types.
Type of OcclusionMaleFemalep-ValueMann-Whitney, U Test
Mean (%)SD (%)Mean (%)SD (%)
I3.01.91.90.80.13610.210261
I/12.82.72.31.80.51420.832379
I/22.31.82.11.20.57730.950579
II2.42.03.01.70.34530.151181
UPC3.01.82.42.10.38390.281809
Table
Table 4. Condyle-plus-ramus asymmetry index (MAI) according to gender and different occlusion types.
Table 4. Condyle-plus-ramus asymmetry index (MAI) according to gender and different occlusion types.
Type of OcclusionMaleFemalep-ValueMann-Whitney U Test
Mean (%)SD (%)Mean (%)SD (%)
I2.01.92.11.10.83980.546631
I/12.21.92.11.70.80270.919097
II/21.81.62.01.30.64110.410383
III2.42.03.01.30.41180.195488
UPC2.31. 62.42.10.84100.796219
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Hlatcu, A.R.; Galan, E.; Milicescu, Ș., Jr.; Teodorescu, E.; Ionescu, E. An Evaluation of the Ramus Mandibular Asymmetry on the Panoramic Radiography. Appl. Sci. 2023, 13, 7645. https://doi.org/10.3390/app13137645

AMA Style

Hlatcu AR, Galan E, Milicescu Ș Jr., Teodorescu E, Ionescu E. An Evaluation of the Ramus Mandibular Asymmetry on the Panoramic Radiography. Applied Sciences. 2023; 13(13):7645. https://doi.org/10.3390/app13137645

Chicago/Turabian Style

Hlatcu, Andreea Raluca, Elena Galan, Ștefan Milicescu, Jr., Elina Teodorescu, and Ecaterina Ionescu. 2023. "An Evaluation of the Ramus Mandibular Asymmetry on the Panoramic Radiography" Applied Sciences 13, no. 13: 7645. https://doi.org/10.3390/app13137645

APA Style

Hlatcu, A. R., Galan, E., Milicescu, Ș., Jr., Teodorescu, E., & Ionescu, E. (2023). An Evaluation of the Ramus Mandibular Asymmetry on the Panoramic Radiography. Applied Sciences, 13(13), 7645. https://doi.org/10.3390/app13137645

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