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Table of Contents
ORIGINAL ARTICLE
Year : 2021  |  Volume : 11  |  Issue : 3  |  Page : 108-113

Evaluation of signs and symptoms of temporomandibular disorders in children and adolescents, before and after rapid maxillary expansion


1 Department of Orthodontics, Bauru Dental School, University of São Paulo, São Paulo, Brazil
2 UNINGA Center, Maringa/PR, Brazil
3 Responsible for the area of TMD and Orofacial Pain of Hospital USP-São Paulo, Brazil and Responsible for the Master's Program in TMD/Orofacial Pain at the São Leopoldo Mandic Dental Research Center – Campinas, São Paulo, Brazil

Date of Submission14-Sep-2020
Date of Decision06-Aug-2021
Date of Acceptance13-Sep-2021
Date of Web Publication22-Dec-2021

Correspondence Address:
Dr. Marcelo Soares Correa
Alameda Octávio Pinheiro Brisolla 9-75, Bauru-SP
Brazil
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/jid.jid_75_20

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   Abstract 

Objective: The purpose of this study was to evaluate the presence of temporomandibular disorder (TMD) signs and symptoms before and after rapid maxillary expansion (RME), in patients with posterior crossbite. Materials and Methods: The sample was comprised of 22 individuals (13 girls, 9 boys), with ages varying from 7 to 14 years (mean: 9.1 years), with posterior crossbite. They were all treated with RME using the Hyrax appliance. They were submitted to a questionnaire of the European Academy of the Craniomandibular Disorder for evaluation of the presence of signs and symptoms of TMD at five different times: T0, T1, T2, T3, Tf (before treatment starts, 15 days after the beginning of the activations, 4, 8, and 10 months after installation of the Hyrax appliance, respectively). If any of the answers to the questionnaire were YES, research diagnosis criteria for temporomandibular disorders - axis I (RDC/TMD-axis I) was applied. Descriptive statistics, Chi-square, and Fisher's exact tests were applied. Results: The initial prevalence of TMD signs and symptoms was 18%. At T2, there was statistically significant improvement (P = 0.046) of TMD signs and symptoms in relation to T0. There was no statistically significant association between sex and TMD signs and symptoms in the five stages that were evaluated. Conclusions: RME temporarily influenced the TMD signs and symptoms in T2. However, there was a return of the TMD signs and symptoms 10 months after installation of the Hyrax appliance.

Keywords: Posterior crossbite, rapid maxillary expansion, signs, symptoms, temporomandibular disorders


How to cite this article:
Correa MS, de Freitas KM, de Freitas MR, Guimaraes AS, Janson G. Evaluation of signs and symptoms of temporomandibular disorders in children and adolescents, before and after rapid maxillary expansion. J Interdiscip Dentistry 2021;11:108-13

How to cite this URL:
Correa MS, de Freitas KM, de Freitas MR, Guimaraes AS, Janson G. Evaluation of signs and symptoms of temporomandibular disorders in children and adolescents, before and after rapid maxillary expansion. J Interdiscip Dentistry [serial online] 2021 [cited 2022 Jan 25];11:108-13. Available from: https://www.jidonline.com/text.asp?2021/11/3/108/333344




   Clinical Relevance to Interdisciplinary Dentistry Top


  • This prospective study assessed 22 individuals during rapid maxillary expansion (RME) treatment and its influence on temporomandibular disorder (TMD) signs and symptoms
  • Intergroup comparisons were performed at pretreatment (T0), 15 days after activation, 4, 8, and 10 months after installation of the Hyrax appliance
  • It was concluded that RME produced only temporary remission of TMD signs and symptoms.



   Introduction Top


Temporomandibular disorder (TMD) is a term that includes a broad spectrum of clinical problems of the temporomandibular joint (TMJ) and muscles in the orofacial area. It is also characterized mainly by pain, TMJ sounds, and irregular or deviated mandibular function. Pain is not of neurogenic, psychogenic or visceral, periodontal, dental, or cutaneous origin.[1],[2]

In a study on TMD in children and adolescents, assessing the prevalence of pain and gender differences, the authors diagnosed 7% of the subjects with TMD pain. The prevalence of pain once a week or more was reported as 21% in the head; 12% in the temples; and 3% in the face, TMJ, or jaws. The prevalence of TMD-related pain was significantly higher in girls than in boys.[3]

Posterior crossbite is defined as any abnormal buccal–lingual relationship between opposing molars, premolars, or both in centric occlusion. The reported incidence of posterior crossbites ranges from 7% to 23% of the population.[4]

Research has shown a correlation between posterior crossbite and signs and symptoms of TMD and suggested that early correction of posterior crossbites may help prevent signs and symptoms of TMD.[1],[5]

Some studies have still suggested that the early treatment of 4 morphological malocclusions associated with orofacial dysfunctions, including the posterior crossbite, to prevent the development of TMD.[6],[7]

A systematic review indicated association between unilateral posterior crossbite with mandibular deviation, and some signs and symptoms of TMD, such as TMJ sounds, clicking, muscle tenderness, and headache.[8]

Historically, occlusal factors were pointed out as an etiological factor of temporomandibular disorders.[9] However, orthodontic procedures do not seem to predispose to TMD signs and symptoms.[10],[11]

On the other hand, in a review article on the etiology of TMDs, the author concludes that not only are the old mechanistic etiological concepts incorrect but also that 2 of the most popular current concepts (biopsychosocial and multifactorial) are seriously flawed. Therefore, what we really noticed in a TMD patient, is almost always an idiopathic situation, where we simply do not know enough, or cannot measure enough, or cannot accurately determine the reason for your TMD.[12]

The purposes of this study were to evaluate whether posterior crossbite correction through rapid maxillary expansion (RME), using the Hyrax appliance, has any influence on TMD signs and symptoms, and to investigate whether there is any correlation between sex and myofascial pain.


   Materials and Methods Top


This prospective clinical study was approved by the Ethics Committee of the Research Center São Leopoldo Mandic–Campinas/SP-Brazil (protocol number: 2008/0214), and all individuals signed a free consent form, agreeing to participate in this study. Thirty individuals from the Cônego Ulisses State School in Campo Belo/MG-Brazil with a posterior crossbite were selected, regardless of race or socioeconomic situation. The inclusion criteria included individuals with complete unilateral or bilateral posterior crossbite requiring maxillary expansion, with ages between 7 and 14 years, who agreed to participate in the study, syndromic individuals were not included. They should be assiduous without missing 2 consecutive appointments.

Sample size calculation

Sample size calculation was based on an alpha error of 5% and a test power of 80%, to detect a minimum change of 5.6° in maxillary first molar buccopalatal inclination, with a standard deviation of 4.3°.[13] Thus, the sample size calculation resulted in the need for 10 patients in each group [Table 1].
Table 1: Sample size calculation using Microsoft Excel 97-2003 for Windows program

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Thirty individuals were interviewed and selected from examinations at public schools, this sample size also was based on some studies with similar methodologies.[14],[15]

Of the 30 individuals, 8 dropped out during the treatment, and thereafter it was not possible to collect their complete information. Then, they were excluded. Therefore, the sample was comprised of 22 patients (13 girls and 9 boys), mean age of 9.1 years, 10 individuals with unilateral posterior crossbite, and 12 individuals with bilateral posterior crossbite, who were referred for treatment of the posterior crossbite.

To correct the posterior crossbite, a 9 mm or 11 mm Hyrax appliance was used, according to the size of the maxillary arch of each individual. The activation protocol consisted of 2/4 turns of the screw in the morning and 2/4 at night, resulting in 1 mm of opening per day of activation for 8–10 days according to each individual's need.[16] The posterior crossbite correction occurred within a period of 8–10 days. After expansion, the Hyrax appliance remained in place for 9 months and 20 days, for retention. The total usage time of the Hyrax appliance was 10 months.

All the patients were submitted to a questionnaire of the European Academy of Craniomandibular Disorders (EACD).[17] The EACD questionnaire was applied by a single examiner to all participants and at all stages of the study. The questions were as follow:

  1. Do you have pain when you open your mouth wide, or chew, once a week or more?
  2. Do you have pain in your temples, face, TMJs, or jaw, once a week or more?
  3. Have you lately registered that the jaw is locked or not able to open widely?
  4. Do you often have headaches, once a week or more?


This questionnaire was applied at 5 different stages:

  • T0 – before treatment starts [Figure 1]
  • T1 – 15 days after activation initiation of the Hyrax appliance [Figure 2]
  • T2 – 4 months after installation of Hyrax appliance [Figure 3]
  • T3 – 8 months after installation of Hyrax appliance
  • Tf – 10 months after installation of Hyrax appliance.
Figure 1: Before treatment starts

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Figure 2: Fifteen days after activation of the Hyrax appliance

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Figure 3: Four month after installation of the Hyrax appliance


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If the patients answered YES to any of the questions, the physical examination protocol for clinical evaluation of TMD signs and symptoms (Research Diagnostic Criteria for Temporomandibular Disorders-RDC/TMD-Axis I)[18] was also applied by the same examiner.

Statistical analysis

The results were tabulated and submitted to descriptive statistical analysis. Data collected were statistically analyzed using IBM® SPSS® for Windows version 18.0 (IBM Corporation, Chicago, IL, USA). Chi-square test was used to evaluate the presence of TMD signs and symptoms during the evaluated stages. Fisher's exact test was applied to evaluate the association between gender and TMD signs and symptoms in all evaluated stages. Results were considered statistically significant at P < 0.05.


   Results Top


The initial prevalence of TMD signs and symptoms in this sample of subjects with posterior crossbite was 18% before the treatment. This means that in T0, 4 of the 22 individuals answered yes to one of the four questions in the EACD questionnaire, specifically to the fourth question, where headache was the TMD symptom reported.

These 4 individuals were submitted to physical examination protocolfor TMD (RDC/TMD-Axis I),[18],[19] and it was found: Subdivision I-Myofascial Pain in all 4 individuals. The TMD signs found in the clinical examination were muscle tenderness upon palpation and mandibular movement limitation. There was statistically significant improvement of TMD signs and symptoms at T2 in relation to T0. At T1, T3, and Tf, there were no statistically significant differences in the signs and symptoms of TMD in relation to T0 [Table 2]. There was no statistically significant association between sex and myofascial pain at all evaluation stages [Table 3].
Table 2: Questionnaire results to evaluate the presence of temporomandibular disorder symptoms, at different times, expressed in absolute and relative values

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Table 3: Association between sex and myofascial pain

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   Discussion Top


In the analysis of the results of this study, with relationship to the age group and signs and symptoms of TMD, the initial prevalence of signs and symptoms before treatment was started, or installation of the Hyrax appliance was 18% [Table 2] as reported in the literature.[20],[21],[22],[23] A study in the same age group found higher prevalence, but these authors used a different methodology[24] and there were reports of higher prevalence, probably due to the highest age group and the use of different, or absence of a clinical dysfunction index.[25],[26]

There was an oscillation of the TMD symptoms (headache) and signs (myofascial pain-subdivision I) reported by the subjects of this research, according to the RDC/TMD-Axis I,[18] physical examination protocol was applied in all evaluated stages, in agreement with some studies.[15],[19],[21],[22],[24],[25],[26],[27],[28],[29]

There was statistically significant improvement, with total remission of TMD signs and symptoms at T2, probably due to temporary reduction in muscle activity by the occlusal changes introduced by RME.[30],[31] However, there was return of the initial symptomatology at T3 and Tf, which means that the occlusal changes may have not necessarily lead to permanent changes in muscle activity[31] [Table 2]. That is, orthopedic treatment for RME with the Hyrax appliance did not induce or prevent the appearance of TMD signs and symptoms in this study period, which corroborates with some studies.[15],[25],[26],[27],[28],[32],[33],[34],[35],[36] The role of orthodontic treatment in precipitation or prevention of TMD is still questionable.[10],[37] Similar studies reported permanent improvement or significant reduction of TMD signs and symptoms after occlusal and/or orthodontic treatments.[9],[38] This may have occurred because diagnostic criteria for temporomandibular disorders were not available. In addition, the cited studies specifically assessed the relationship of occlusal interference and TMD, rather than the relationship of morphological malocclusion and TMD.

Posterior crossbite is a morphological malocclusion, and in this study, it does not seem to represent a TMD etiological factor by itself, which is in agreement with some studies that have not found a significant relationship between different types of morphologic malocclusion and TMD signs and symptoms.[24],[33],[37],[39],[40],[41] Researchers considered it as a risk factor for TMD development, and recommend early treatment to prevent future onset of TMD signs and symptoms, or showing a significantly higher prevalence of TMD signs and symptoms in the presence of this morphological malocclusion.[1],[5],[20],[22],[28],[29],[36],[42] There are those who recommend early treatment of posterior crossbite to improve the functional and development conditions of the patients, and they do not recommend it to prevent the onset of TMD signs and symptoms.[14],[21] In addition, they state that this correction does not guarantee the absence of functional disorders in the future.

There was no statistically significant association between sex and the presence of TMD signs and symptoms before and after correction of posterior crossbite[20],[37] [Table 3]. There are studies that reported greater prevalence of TMD signs and symptoms in females, and this may be due to the larger number of subjects in the samples analyzed.[22],[28],[42]

The only reported symptom in this study was headache, which corroborates with studies in the same age group.[21],[22],[28],[29] The TMD clinical sign found, according to the RDC/TMD protocol performed in the individuals of this research, was myofascial pain-muscle tenderness upon palpation, which corroborates with studies in the same age group.[21],[24],[29]

There was no significant correlation between posterior crossbite and TMD signs and symptoms because even after posterior crossbite correction and occlusal stabilization, 10 months after Hyrax appliance installation (Tf), the initial TMD symptoms returned, suggesting that there are other important factors in TMJ dysfunction and pain etiology, reinforcing the multifactorial characteristic of the TMD etiology.

Limitations and recommendations

It can be argued that the sample size in the present study was too small to produce significant results. Hence, it is recommended to conduct future research taking a larger population to study posterior crossbite and TMD signs and symptoms relationship in view of the complexity and the large number of TMD etiological factors. However, it is important to emphasize the impossibility of using a control group, due to ethical reasons.


   Conclusions Top


Within the limitations, it can be concluded from the present study that:

  • RME temporarily influenced the TMD with total remission of TMD signs and symptoms 4 months after installation of the Hyrax appliance
  • However, there was return of the TMD signs and symptoms 10 months after installation of the Hyrax appliance.


Financial support and sponsorship

The study was financed in part by the “Coordenação de Aperfeiçoamento de Pessoal de Nível Superior” (CAPES) Brazil – Finance Code 001.

Conflicts of interest

There are no conflicts of interest.



 
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  [Figure 1], [Figure 2], [Figure 3]
 
 
    Tables

  [Table 1], [Table 2], [Table 3]



 

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