Prevention and treatment of recurrence of abnormalities of occlusion and dentition deformities: kinesiologic aspect

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Authors

  • N.M. Didenko 1, PhD in Medical Sciences, assistant professor of the Prosthetic dentistry Department
    ORCID ID: 0000-0003-1440-2484
  • A.V. Stefanidi 2, PhD in Medical Sciences, professor of the Medical rehabilitation Department
    ORCID ID: 0000-0002-1447-7032
  • N.V. Mamonova 3, PhD in Physics and Mathematics, associate professor of the Mathematical methods and digital technologies Department
    ORCID ID: 0000-0002-0169-9170
  • A.Ya. Vyazmin 1, PhD in Medical Sciences, full professor of the Prosthodontics Department
    ORCID ID: 0000-0001-0870-5012
  • E.V. Mokrenko 1, PhD in Medical Sciences, associate professor of the Prosthodontics Department
  • V.V. Gazinskiy 1, PhD in Medical Sciences, assistant professor of the Prosthetic dentistry Department
    ORCID ID: 0000-0002-0390-9768
  • 1 Irkutsk State Medical University, 664003, Irkutsk, Russia
  • 2 Irkutsk State Medical Academy of Postgraduate Education, 664049, Irkutsk, Russia
  • 3 Baikal State University, 664003, Irkutsk, Russia

Abstract

Dental interventions are carried out without taking into account posturologist aspects in the treatment of disorders of occlusion. Purpose of the study — prediction of the effectiveness of orthodontic and orthopedic treatment of occlusion disorders combined with methods of manual diagnosis and therapy of musculoskeletal dysfunction.
Materials and methods.
To study the problem we analyzed the interrelation of occlusion and posture disorders, clinical manifestations of anomalies of occlusion of dentition and posture in a group of 175 patients aged 18 to 63 years, who underwent orthodontic treatment of occlusive disorders, followed by the study of long-term results for 5 years. Among all the examined patients 38 people showed signs of recurrence of occlusion abnormalities. At the suggestion of neurologists, we examined patients (38 people) with signs of recurrence of occlusive malocclusion during the functional load on the spine and foot. The one of the dynamic violation of the path of movement of the lower jaw when opening mouth — the deviation of the top of the chin away from the midline of the face is estimated in these three provisions. The evaluation of the data was carried out using statistical methods of variance and correlation analysis, determined the criteria of Fisher and Student.
Findings.
When comparing the revealed deviation of the mandible in patients with poor catamnesis in three functional states of patients, we found the following types of biomechanical features of the trajectory of its movement: I. The deviation of the mandible did not change in the standing and sitting position, unlike the deviation detected initially in the dental chair — in 3 (7.9%) people; II. The deviation of the lower jaw increased or changed in the opposite direction in the standing position in contrast to the deviation detected initially in the dental chair — in 15 (39.5%) people; III. A more pronounced deviation of the lower jaw was noted in the sitting position on the chair, unlike the deviation initially detected in the dental chair — in 20 (53%) people. Group II included patients with skull bone dysfunction — 6 people out of 15 (40% of patients), group III — patients with unexpressed flat feet — 5 people out of 20 (25%), etc.
Conclusion.
In group I of patients (3 persons) the revealed deviation of the mandible did not change in all listed functional states of the HMS. These patients underwent correction of occlusive ratios of dentition, recommendations on the use of retention orthodontic devices, as well as correction of posture in the clinic of manual therapy. In group II 15 patients were found to have pronounced and asymmetric flat feet on both feet. Before the treatment of occlusive disorders of the patients of the second group recommended the production of individual insoles to correct the support function of the feet and restore postural equilibrium of the body. In 20 patients of group III, pronounced dysfunction of the skull bones and pelvic dysfunction in the form of twisting of the pelvic bones were found. In this group of patients we determined descending ode dysfunction. Before the beginning of orthodontic correction the group III patients underwent manual therapy of the cranial department with functional study of the muscles of the maxillofacial region, cervical, thoracic and pelvic spine.

Key words:

occlusion, posture, pose, orthodontic treatment, deviation

For Citation

[1]
Didenko N.M., Stefanidi A.V., Mamonova N.V., Vyazmin A.Ya., Mokrenko E.V., Gazinskiy V.V. Prevention and treatment of recurrence of abnormalities of occlusion and dentition deformities: kinesiologic aspect. Clinical Dentistry (Russia).  2021; 24 (2): 104—110

Introduction

The diagnosis of malocclusions and dental malformations in adult patients in an orthopaedic dentistry clinic is generally not difficult for a dentist. A number of researchers have proved the relationship between abnormal occlusion disorders and posture [1—6]. The clinical manifestations of malocclusions in patients with abnormalities of body position in space — posture — were studied [7—15]. In some clinical cases, this fact helps to explain the unsatisfactory results of orthodontic and orthopaedic treatment, its duration, complications and recurrence of malocclusions and dental deformities. The fact is that during check-up and treatment in an orthopaedic dentistry clinic, patients are in a dental chair (a reclining position). In this way, their head is fixed by the headrest and the spine is supported by the back of the saddle, the neck and back are relaxed and the locomotion system (LMS) does not support the body's balance. When a patient sits in a chair without back and head support, especially when standing up, the postural factors of body balance come into play [15,16]. Dental procedures, in particular prosthetics or filling aimed at correct occlusal relations, and orthodontic treatment are carried out with no regard to kinesiological aspects when treating malocclusions [17].

It is difficult for a dentist in an orthopaedic dentistry clinic to understand the true causes of recurring malocclusions after dental treatment in patients with posture disorders. What forms of LMS disorders form recurrent malocclusions? Can the biomechanics of mandible movements during mouth opening change with different functional conditions of the spine? How to evaluate the effectiveness of a dental procedure based on the diagnosis and treatment of LMS disorders? What was the cause: structural changes in the cranial region, imbalances in the maxillofacial region, in particular the function of the masticatory muscles, or LMS disorders of a patient? The purpose of the paper is to predict the effectiveness of orthodontic and orthopaedic treatment of malocclusions combined with manual diagnosis techniques and therapy for LMS dysfunctions.

Materials and methods

A total of 175 patients aged 18 to 63 years were examined. From 2008 to 2012, they underwent orthodontic treatment for occlusal dental disorders at the Orthopaedic Dentistry Clinic of the Irkutsk State Medical University, followed by a 5-year study of the long-term results. Among all those examined, 38 (21.7%) patients showed signs of recurrent occlusal anomalies (Table 1).

Visual inspection of occlusal contacts, teeth in central, anterior, lateral and dynamic occlusion during mandibular movement was performed in three mutually perpendicular directions. The identified recurrences of the abnormal dentition occlusion were grouped according to the main directions: sagittal, transversal and vertical.

The assessment of LMS function parameters was carried out using the technique of examining a patient in the upright position, when the forces of gravity come into play, which makes it possible to evaluate the function of the postural system, namely posture formation [5]. The position of the anatomical landmarks of the head, body, legs and arch of the feet were identified in relation to the reference line — the vertical axis of the body in the frontal (displacement), sagittal (displacement) and horizontal planes (rotation). Paired anatomical landmarks of the body connected by straight lines were assessed. In order to analyze the causes leading to unsatisfactory outcomes in the patient’s follow-up, 38 people with signs of recurrent malocclusions during functional load on the spine and feet were examined at the suggestion of neurologists.

Patients were examined in three basic positions: in a reclining position with head and back support in a dental chair (we characterize this position as a functional or physiological resting position of the spine); in a seated position in a chair without back and head support (a position of functional load on the spine) and in an upright position (a position of functional load on the spine and the feet).

In these three positions, the deviation of the chin apex aside from the facial midline, one of the dynamic signs of an impaired mandibular path when opening the mouth, is assessed. The data were scored using statistical methods of the variance and correlation analysis, with Fisher's and Student's tests.

A variance analysis of clinical characteristics in patients before treatment and those with poor catamnesis was performed to determine the effect of malocclusions combinations in the main directions on the shape of malocclusions. Analyzing the data and using Fisher's test (F), the following results were obtained at a significance level of 5%.

Results

For patients examined before orthodontic treatment, statistics showed no significant relevance in the direction or form of malocclusions. Both indicators were statistically insignificant, the significance of the indicator was p=0.258. In contrast, for patients with poor catamnesis, statistical significance was determined by the form of malocclusions (gnathic and articular), the significance of the indicator was p=0.034. F is equal to 12.72, which is clearly above the critical point of 9.55.

Thus, the hypothesis, according to which the influence of the malocclusion form factor is insignificant, is rejected, and the importance of the malocclusion form in people with a poor dental history can be stated with 95% confidence (Fig. 1). Severe combined locomotive disorders in the form of spinal scoliosis, flat feet and skull bone deformity were detected in 35 (92.1%) people with poor catamnesis (Table 2). Among 137 people with a satisfactory catamnesis, the following LMS disorders were identified: flat feet in 32 (23.3%) people, scoliosis in 29 (21.1%) people and skull bone deformity in 22 (16.1%) people. Only 14 (10.2%) patients had combined forms of dysfunction, and these were not pronounced.

Fig. 1. Number of patients before orthodontic treatment and the number of patients with unsatisfactory follow-up

The visual representation of a correlation between clinical features of LMS allows us to ascertain that the incidence of an unpronounced form of LMS is higher in patients with a satisfactory catamnesis than in those with an unsatisfactory catamnesis, so that unpronounced dysfunctions of LMS in patients with NF are more significant. Consequently, these disorders were not combined and were less pronounced (Fig. 2). When comparing an identified deviation of the mandible in patients with poor catamnesis in three functional states, the following types of biomechanical features of its trajectory were found (Table 3):

  1. Mandibular deviation did not change when standing or sitting, in contrast to the deviation initially detected in 3 (7.9%) persons in the dental chair;
  2. Mandibular deviation increased or reversed when standing, in contrast to the deviation, initially detected in 15 (39.5%) persons in the dental chair;
  3. More pronounced mandibular deviation when sitting in the chair, in contrast to the deviation initially detected in 20 (52.6%) persons in the dental chair.
Fig. 2. The indicators ratio of the unpronounced form of musculoskeletal dysfunction in patients with satisfactory and unsatisfactory catamnesis

The correlation analysis and Student's criterion were used to investigate clinical characteristics of LMS changes by groups of detected deviation. This made it possible to assess the correlation between varying degrees of LMS dysfunction with changes in mandibular trajectory (deviation) in different patient groups. The percentages of available data were investigated.

In the smallest group I of patients (3 patients), the detected mandibular deviation was unchanged in all listed functional states of LMS. These patients showed signs of a partial recurrence of an occlusal anomaly. There is a tendency for the mandible to move back to its previous position. It was found that after orthodontic treatment, patients stopped using retention devices early on and did not see an orthodontist. These patients underwent correction of the occlusal dentition, were given recommendations for the use of retention orthodontic devices, as well as posture correction in the manual therapy clinic.

So, group II included patients with cranial bone dysfunction in 6 of 15 (40% of patients), group III included patients with unpronounced flatfoot in 5 of 20 (25%), etc.

In group II of patients there was a high inverse correlation between the presence of skull bone dysfunction and severe flatfoot (r=0.9998), i.e. the more pronounced the flatfoot, the less frequent is the skull bone dysfunction. In group III of patients, there was a high correlation between the effect of pelvic bone dysfunction and cranial bone dysfunction (r=0.998), i.e. the more often patients show pronounced dysfunctions in the cranial bones, the more often pronounced dysfunctions are found in the pelvic bones. A high r-value indicates a significant correlation between the indicators in question, with Student's t-test at the 5% significance level.

Conclusion

In group II, 15 patients were found to have pronounced and asymmetrical flatfoot in both feet. It is known that impaired support function of the foot leads to ascending LMS pathology, impaired postural tone of the masticatory muscles and a craniomandibular dysfunction [7—10, 18]. This, in turn, leads to changes in the biomechanics of mandibular movements and consequently changes the occlusion [5—7, 10—13, 19], so in these patients, mandibular deviation was exacerbated in an upright position with pronounced asymmetric flatfoot. We defined the totality of abnormalities found in this group of patients as an ascending dysfunction.

Before treatment of patients in group II, it is recommended to make individual insoles to correct the supportive function of the feet and to restore postural balance of the body. After orthodontic treatment, patients were referred to osteopathic physicians to balance the postural muscles.

In group III, 20 patients were found to have severe cranial and pelvic bone dysfunction in the form of pelvic bone torsion. In this group of patients, we defined a descending LMS dysfunction.

The primary change was in the skull bones, with a skull dysfunction manifested by external rotation of the temporal bone on one side and internal rotation of the temporal bone on the other. They led to scoliosis in the cervical and thoracic spine and were accompanied by a rotational pelvic bone dysfunction [20—23]. In a seated position, without support in the lumbar and thoracic spine, a person with scoliosis who has an imbalance in deep muscles of the spinal column has to have his head constantly supported. The splenius and sternocleidomastoid muscles in the neck, which are the antagonists of the temporal and masseter muscles, are strained. The tone of these muscles changes [24—29], which leads to a disturbance of the dynamic occlusal relationship of the dentition and ultimately to a recurrence of the occlusal anomaly [30—35].

Before orthodontic correction, group III patients underwent a course of cranial manual therapy with functional work on the maxillofacial, cervical, thoracic and pelvic spine muscles. Once orthodontic and orthopaedic dentistry had been completed, the patients were referred back to the manual therapy clinic to consolidate the satisfactory results obtained with the complex treatment of malocclusions.

Summary

  1. Profound and combined forms of LMS disorders create conditions for recurrences of malocclusions after orthodontic treatment.
  2. Dynamic signs of mandibular biomechanics should be considered. This helps to prevent the formation of recurrent malocclusions.
  3. In the ascending LMS dysfunction, the support function of the feet and postural balance must be normalised before starting orthodontic treatment.
  4. In the descending LMS dysfunction, osteopathic influence on the cranial cranium, maxillofacial region, cervical, thoracic, and pelvic spine is necessary to achieve the most effective and stable treatment of occlusal anomalies and dental deformities.
Table 1. Clinical characteristics of occlusive disorders in patients examined before orthodontic treatment and recurrences of occlusive disorders in patients with a catamnesis of 5 years or more after orthodontic treatment
Predominant direction of occlusal disorders n=175 n=38
gnathic articular dentoalveolar gnathic articular dentoalveolar
Sagittal 8 24 65 8 8 2
Transversal 12 16 38 12 7 1
Vertical 3 — 9 — — —
In total 23 40 112 20 15 3
Table 2. Results of clinical examination of patients with catamnesis for 5 years or more
A plane where musculoskeletal changes are found Unsatisfactory catamnesis
(n=38)		 Satisfactory catamnesis
(n=137)
scoliosis pelvic bone dysfunction flatfoot combined form of dysfunction cranial bones dysfunction scoliosis pelvic bone dysfunction flatfoot combined form of dysfunction cranial bones dysfunction
Sagittal pronounced dysfunction 14 12 10 12 10 0 0 0 0 0
unpronounced dysfunction 1 1 1 2 1 5 7 8 8 9
Frontal pronounced dysfunction 10 14 11 7 10 0 0 0 0 0
unpronounced dysfunction 0 2 7 1 2 12 22 14 16 0
Horizontal pronounced dysfunction 11 9 14 16 15 0 0 0 0 0
unpronounced dysfunction 2 0 0 0 0 5 0 7 8 5
Table 3. Clinical characteristics of locomotion changes by groups of revealed mandibular deviation in patients with poor catamnesis
Locomotive disorder Reaction type group
I II III
Cranial bones dysfunction Explicit 0 6 20
Unexpressed 1 9 0
Scoliosis Explicit 0 10 19
Unexpressed 3 4 1
Pelvic bone dysfunction Explicit 0 15 20
Unexpressed 0 5 5
Flatfoot Explicit 0 15 1
Unexpressed 0 0 5
Combined forms 0 15 14

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January 31, 2021

Accepted

March 18, 2021

Published on

June 1, 2021