2020, Number 2
Association of dentoesqueletal characteristics in patients with different degrees of dentoalveolar discrepancy
Full text
Language: English/Spanish [Versión en español]
References: 15
Page: 81-89
PDF size: 210.65 Kb.
ABSTRACT
Introduction: Dentoalveolar discrepancy (DD) is a very common malocclusion that strongly determines the conditions of orthodontic treatment; even so, the distribution of the alterations present in the different degrees of DD is not entirely clear. Objective: To determine the association of bone and dental alterations in the different degrees of DD. Material and methods: A comparative cross-sectional study was carried out to determine the different alterations present in people with different degrees of DD with conventional orthodontic analysis. Results: Moderate and severe DD were the most frequent types. The distribution of the alterations was generally similar between the DD groups; though, ovoid-shaped and triangular-shaped gradually increased with the degree of DD. In contrast, class I skeletal decreased as DD increased. Conclusions: Possibly the type of DD is not an indicator for the occurrence of specific bone and dental alterations of DD; nevertheless, the severity of crowding could predispose triangular-shaped maxillary archs.INTRODUCTION
Among the malocclusions, dentoalveolar discrepancy (DD) is one of the most notable manifestations, due to the repercussions it has on the social, aesthetic and oral function of the patient, as it has a direct impact on the occlusion, on the predisposition to cavities and on the affectation of the periodontal tissues, due to the difficulty in performing adequate hygienic oral habits.1 According to the World Health Organisation, malocclusions are the third most common oral disease, after caries and periodontal diseases.2,3
DOD is one of the dental disorders associated with a large part of the world's population for several hundred years, as knowledge of "crowded teeth" dates back to the time of Hippocrates, Aristotle and Celsus.1 DD is defined as the difference between the measurement of the alveolar ridge of the arch and the summation of the mesio-distal width of the dental organs, and can be classified as mild, moderate and severe. Its aetiology is considered multifactorial, however, the distribution has been found to be associated with the type of population.4,5 DD varies in individuals and there may be several associated factors in the same person, with greater complication occurring when skeletal or muscular problems are involved.6
The diagnostic methods that help us to identify and assess DD are clinical examination, photographs and study models. Although there are general studies that have determined the general characteristics of the various degrees of dental crowding,7,8 there is no such information recently available for patients living in the northern part of Mexico. The aim of this study was to evaluate the levels of association of the various degrees of DOD with the diverse osteo-dento-skeletal alterations present in people living in Ciudad Juárez, Chihuahua.
MATERIAL AND METHODS
A cross-sectional, comparative and retrospective study was carried out on patients who attended the Orthodontic Clinic of the Autonomous University of Ciudad Juárez for consultation in 2012, reviewed and approved by the Research Committee of the Master's Degree in Odontological Sciences of the same university. Clinical histories, study models, radiographs and photographs of the patients were reviewed and evaluated through consecutive non-probabilistic sampling. The study groups were determined according to the level and analysis of DD: 1. Mild crowding (< 2.9 mm), 2. Moderate crowding (3-5.9 mm), and 3. Severe crowding (> 6 mm). Additional subgroupings were performed, where the subgroup with DD included groups 2 (moderate DD) and 3 (severe DD); and the subgroup without DD included group 1 (mild DD). Assessments determined demographics, clinical, extra and intraoral assessment, cephalometric characteristics through Steiner Analysis, Jaraback Analysis and study model analysis.
Statistical analysisAll data were expressed as frequency, percentage, mean and standard deviation. Differences between groups were determined with the χ2 test and risk associations under the odds ratio (OR) test. All statistical tests were performed with IBM-SPSS v23 software and significant differences were considered when the p-value 0.05.
RESULTS
Table 1 shows the results derived from DD and sex in the different dentoalveolar discrepancy groups. In general, age was statistically equal in all DD groups (p > 0.05). On the other hand, the sex variable showed a higher distribution among females (67.9-68.6%) in all DD groups compared to males (31.4-32.1%); nonetheless, no statistical difference was identified. This indicates that the age and number of males and females were evenly distributed in all crowding groups.
Table 2 shows the results of the different dentofacial alterations in the DD groups. The highest frequencies were identified in class I molar (40.0-47.1%), followed by class II (32.9-41.1%) and class III (15.7-16.4%). The lowest frequency was represented by class indeterminate (2.9-3.6%) which was similarly expressed in all DD groups (p > 0.05). The collapsed maxillary arch was very infrequent in the different types of DD (12.7-16.8%), being observed equally in the DD groups (p > 0.05). On the other hand, class III skeletal was the least frequent (5.9-10.7%), followed by class I (43.1-49.4%) and II (43.1-49.4%) among the DD groups, finding a significant difference (p = 0.03). The three biotypes behaved similarly in the DD groups (p > 0.05), with the normofacial biotype having the highest frequencies in the DD groups (mild = 47.3%, moderate = 35.0% and severe = 40.2%) contrasted with the brachyfacial (mild = 23.2%, moderate = 32.9% and severe = 21.7%) and dolichofacial (mild = 29.5%, moderate = 32.1% and severe = 38.1%).
Oral habits were expressed in a statistically similar way in the DD groups (p > 0.05), identifying the most frequent habit as tongue (10.7-13.7%), followed by lip (6.9-10.7%), nail (7.2-8.4%), mouth breathing (2.9-8.4%) and the least frequent finger (1.9-7.9%). Overbite and overjet manifested very similarly in the DD groups (p > 0.05); for both types (overbite and overjet), the most frequent was normal (53.0-71.6%), followed by augmented (23.2-37.2%) and the lowest frequency was negative (5.2-9.8%). On the other hand, the maxillary arch showed a more accentuated distribution in ovoid-shaped-shaped (67.6-83.1%), triangular-shaped (7.4-23.5%) and square-shaped (7.9-9.5%) for all groups. In addition, we found a statistically significant difference in maxillary arch form (p = 0.03) finding that the frequency of ovoid-shaped arch gradually decreases with DD severity (mild = 83.1%, moderate = 77.1% and severe = 67.6%), while the triangular-shaped shows an opposite trend to the previous shape in which the frequency increases with DD severity (mild = 7.4%, moderate = 15.0% and severe = 23.5%). On the other side, the shape of the mandibular arch was shown to be very similar to the upper arch but with no significant difference between the DD groups (p > 0.05). These results indicate that the distribution of dentofacial alterations, which are distributed differently in the study groups, are related to the shape of the maxillary arch.
Table 3 shows the risk associations between the presence of DD and bone and dental alterations. It can be seen that the presence of alterations such as class II and III molar (61.1%) and maxillary collapse (16.8%) had higher frequencies in the group without DD than in the group with DD (53.3% and 14.9%, respectively). In another aspect, maxillary triangular-shaped and square-shaped, and class II and III skeletal forms were more frequent in the DD group; however, the only statistically significant risk association was found in the presence of maxillary triangular-shaped and square-shaped, when related to the presence of DD (OR = 1.813; 95% CI = 0.978-3.330; p = 0.05). This suggests that triangular-shaped and square-shaped could act as a risk element for the occurrence of more severe levels of DD.
DISCUSSION
The present study demonstrated the significant association between the different DD grades with class I skeletal and triangular-shaped and ovoid-shaped, both in the upper arch. Nonetheless, maxillary triangular-shaped and square-shaped, were shown to have risk associations for developing more severe stages of DD. This is the first report in Mexico in the scientific literature that identifies a significantly close relationship between the different degrees of DD and the particular craniofacial conditions of people living in Ciudad Juárez, Chihuahua, Mexico. The results should be widely promoted as they can be used for more timely diagnosis, more efficient treatment plans and, at certain points, in the development of more predictable prognosis during and after orthodontic care.
The triangular-shaped upper arch is likely to be closely related to oral habits that may occur in growing patients.
A Latin American study of 138 Cuban adolescents reported a slightly higher frequency of DD in females (50.8%) than in males (49.2%), indicating that mandibular crowding was more frequent than in the maxilla (44.2 and 23%, respectively), while mild DD was the most prevalent (64.2%).9 In addition, a survey of 1,197 people aged 5-15 years showed that females (52.6%) were more affected than males (47.4%)5 was the group more affected by some form of crowding. Also, other epidemiological studies also conducted in adolescents, have found relatively high prevalences of DD (20-69.3%) with severe DD, which was predominantly found, requiring a more specialised treatment.6-8
On the one hand, a study of 1082 patients from a population in Pakistan found that class II molar division I was the most prevalent malocclusion while mild DD in both maxilla and mandible were the most frequent (24.6 and 28.8%, respectively). Similarly, statistically significant associations were determined between DD level and class molar category (angle classification), particularly in the class II subdivisions. Suggesting that higher levels of DD (moderate and severe) were more frequently observed in class I molar patients, whereas lower levels of DD (normal and mild) were more frequent in class II molar subdivisions.10 Studies have evaluated the distribution of different arch shapes, for example, in a study of Korean individuals, the square-shaped predominated (46.7%), with ovoid-shaped and triangular-shaped being less frequent (53%). In contrast, in a Caucasian population, ovoid-shaped and triangular-shaped were more predominant (80%) compared to square-shaped (18.1%).11
Another study in a Chilean population found similar distributions in the three arch shapes (ovoid-shaped 39%, square-shaped 35% and triangular-shaped 26%).12 In contrast, a study in South Americans reported that in the maxilla and mandible, the ovoid-shaped was the most predominant (86 and 75%, respectively), and the least frequent was the square-shaped (14% for the maxilla and 25% for the mandible), and that the triangular-shaped did not occur in any of the arches.13 Furthermore, a study in Chilean individuals found that the most common was ovoid-shaped (55%) followed by square-shaped (27.5%) and triangular-shaped (17.5%), concluding that there is a low overlap in upper and lower arch shapes within the same person.14 Our study found that the most common type of DD was moderate (41.5%) followed by severe (30.2%) and mild (28.1%). The distribution of the types of DD was statistically similar in relation to the various dento-skeletal alterations such as type of molar class, presence of maxillary collapse, facial biotype, oral habits, type of overbite, among others (p > 0.05). Nevertheless, the only dento-skeletal alterations that showed statistically significant associations with DD severity were class skeletal and maxillary arch form (p < 0.05). The presence of triangular-shaped and square-shaped was identified as a risk element for the occurrence of higher levels of DD (OR = 1.813; 95% CI = 0.978-3.330; p = 0.05). This may indicate that increasing severity of DOD may influence the gradual decrease in the frequency of class I skeletal and oval-shaped maxilla, thereby increasing the presence of class II skeletal and triangular-shaped maxilla. However, triangular-shaped and square-shaped may represent a risk for the development of more severe stages of DD.
In this regard, it is possible that the class I skeletal and ovoid-shaped of the maxilla, in the presence of more severe stages of DD, may establish an increased risk for the development of class II skeletal and triangular-shaped maxillary morphologies that facilitate maxillary collapse.15 At the same time, the triangular-shaped and square-shaped present in the maxillary arch may increase the risk of developing more complex cases of DD. Our study suggests that particular osseodento-skeletal alterations may be related to the presence and severity of DD, it is possible that other factors such as heredity, race, oral habits, culture, place of origin and other socio-demographic factors may be related to each type of DD present in people living in Ciudad Juárez.
Nowadays, the various bone and dental alterations identified in patients undergoing conventional orthodontic treatment are considered a clinical challenge before, during and after orthodontic treatment. The present study methodologically included an adequate number of patients in each study group, analysed by cephalometric testing and highly complementary orthodontic analysis. We suggest that other studies include continuous quantitative variables derived from the same tests used in orthodontics and surely a modification in the type of statistical analysis for the determination of risk factors involved in the development of DD.
CONCLUSIONS
This study found significant associations between DD severity and Class I skeletal as well as triangular-shaped and ovoid-shaped of the maxilla, also, these shapes showed significant associations for the development of more severe levels of DD, suggesting that particular shapes of the upper arch could directly influence the development of more severe stages of DD. Diffusion of these results to clinicians in the field of orthodontics is of utmost importance, as well as to other health sectors for the improvement of preventive measures and treatment of bone and dental alterations such as DD, mainly in people from Ciudad Juárez, Chihuahua.
ACKNOWLEDGEMENTS
The authors would like to thank the Department of Stomatology of the Institute of Biomedical Sciences of the Autonomous University of Ciudad Juárez for their support in carrying out this study.
REFERENCES
AFFILIATIONS
1 Maestría en Ciencias Odontológicas. Departamento de Estomatología. Instituto de Ciencias Biomédicas, Universidad Autónoma de Ciudad Juárez, Ciudad Juárez, Chihuahua, México.
2 Especialidad en Ortodoncia. Departamento de Estomatología. Instituto de Ciencias Biomédicas, Universidad Autónoma de Ciudad Juárez, Ciudad Juárez, Chihuahua, México.
3 Especialista en Odontopediatría, Especialidad en Odontopediatría. Departamento de Estomatología. Instituto de Ciencias Biomédicas, Universidad Autónoma de Ciudad Juárez, Ciudad Juárez, Chihuahua, México.
CORRESPONDENCE
Dr. Omar Alejandro Hernández Cepeda. E-mail: omar.hernandez@uacj.mxReceived: Noviembre 2019. Accepted: Enero 2020.