Analiza elektromiograficznych wskaźników mięśni skroniowych i mięśni żwaczy u chorych z tyłozgryzem powikłanym stłoczeniem zębów

Maryna I. Dmytrenko

Department of Orthodontics, Higher State Educational Establishment of Ukraine “UKRAINIAN MEDICAL STOMATOLOGICAL ACADEMY”, Poltava, Ukraine

ABSTRACT

Introduction: Rate of distal occlusion (up to 40%) and dental crowding (up to 65%) is the largest in the structure of orthodontic pathology.

The aim of the study was to investigate bioelectrical activity of temporal and masticatory muscles and to set parameters of electromyographic indexes in patients with distal occlusion and dental crowding in permanent occlusion.

Materials and methods: Bioelectrical activity of temporal and masticatory muscles in 11 patients aged 16-24 years was determined before orthodontic treatment. Distal occlusion complicated by severe degree of dental crowding was revealed in this group of patients. These patients comprised the treatment group. The control group consisted of 10 subjects (mean age 21,3 ± 1,25 years) with physiological occlusion.

Results: It was found that functional state of temporal and masticatory muscles in patients with distal occlusion complicated by dental crowding changes during permanent dentition. It was determined that in clenching state, according to ACTIV index, temporal muscles are more active, due to the lack of activity of masticatory muscles (ACTIV =-20,73% ± 8,01%). Moreover it is worthy of notice, that functional muscle symmetry (index SIM TА/MМ) at rest in presence of distal occlusion is lower than in subjects with physiological occlusion (p <0,05).

Conclusions: According to index АCTIV TА/MМ it was established the dominance of temporal muscle activity due to lack of activity of masticatory muscles in patients with distal occlusion complicated by dental crowding and it was determined lower overall muscle symmetry index than in individuals with physiological occlusion.

Wiad Lek 2018, 71, 2 cz. II, -298

 

INTRODUCTION

Frequency of abnormal occlusion during mixed dentition is 79,96% and during permanent dentition is 84,33% [1]. It was established that rate of distal occlusion (up to 40%) and dental crowding (up to 65%) are the largest in the structure of dental pathology [1]. Interralation between electromyographic (EMG) activity of masticatory muscles and morphological disorders contributes to understanding of etiology and pathogenesis of malocclusion and provides the development of rational methods of treatment [2, 3]. However, there is not enough data in literature about the importance of violations of bioelectrical activity of masticatory and temporal muscles in diagnostic process and complex treatment of patients with distal occlusion complicated by dental crowding in permanent occlusion.

THE AIM

The aim of the study is to investigate bioelectrical activity of masticatory and temporal muscles and to set parameters of electromyographic indexes in patients with distal occlusion complicated by dental crowding in permanent occlusion.

MATERIALS AND METHODS

Bioelectrical activity of temporal and masticatory muscles in 11 patients aged 16-24 years was determined before orthodontic treatment. Distal occlusion complicated by severe degree of dental crowding was revealed in this group of patients. These patients comprised the treatment group (I). The control group (II) consisted of 10 subjects (mean age 21,3 ± 1,25 years) with physiological occlusion.

Electromyographic (EMG) activity during the first 5 seconds in state of physiological rest and during performing functional test: maximum voluntary clenching of teeth in habitual occlusion (5 s), was recorded. The average values of oscillation amplitude (microwaves) of muscles biopotentials (BP) on both sides were determined. Quantitative analysis calculated EMG-indixes [4]: asymmetry index of symmetric muscles, separately for temporal (ASIMTА, %) and masticatory muscles (ASIMMМ, %) as well as overall index (ASIMTА/MМ, %.)
Muscles activity index (ACTIV,%) and torsion coefficient (TORS,%) were calculated too. Absolute value of indicators of asymmetry, module of indicators (MASIM) were determined. With regard to them indicators of symmetry were calculated by the following formula: symmetry index (SIM,%) = 100 – absolute value of asymmetry index (MASIM, %). Finding obtained in the study were processed by mathematical statistics methods.

RESULTS AND DISCUSSION

Results of oscillation amplitude (microwave) of investigated muscles biopotentials (BP) are given in Table І. In assessing amplitude of BP of temporal and masticatory muscles in state of relative physiological rest no statistically significant difference in groups was found (p> 0,05).

Analysis of oscillation amplitude of muscles BP in clenching also showed that there is no statistically significant difference in EMG activity of temporal muscles in both groups. Meanwhile, average BP of masticatory muscles in patients with distal occlusion and dental crowding were lower compared to the control group.

When comparing the asymmetry index (ASIM) in state of relative physiological rest balance upset of right and left muscles was observed: great activity of temporal muscle was observed more often (high ASIM index) on the right side, and activity of masticatory muscles on the left side (low ASIMMM index) (Table ІІ). In subjects with physiological occlusion overall asymmetry index was the lowest (ASIM TA/MM = 1,01% ± 3,92%), that is temporal and masticatory muscles functioned more symmetrically than in patients with orthodontic pathology (p> 0,05).

It was established that in patients with distal occlusion complicated by dental crowding, parameters of functional muscle symmetry were low (SIM TA/MM = 78,54% ± 4,24%). It is statistically proven that index SIM TA/MM in patients of the main group in state of physiological rest was significantly lower (p <0,05), than in the control group.

When comparing index of muscles activity (ACTIV, %) in experimental groups it was determined higher temporal muscle activity (negative ACTIV % index), it was (ACTIV) = -20,73% ± 8,01%) particularly in patients with distal occlusion.

In evaluating the torsion coefficient (TORS, %) in experimental groups its positive values were determined. It denotes excitation what attempts to reject the lower jaw to the right.

A number of current researches [5, 6] identified similar deviations in functional state of masticatory muscles in patients with distal occlusion during temporal dentition. It manifested in damping of BP of masticatory muscles in clenching and spontaneous muscles activity in state physiological rest; temporal muscles predominant influence on the formation of occlusion.

CONCLUSIONS

Therefore, the investigation has indicated that functional state of temporal and masticatory muscles in patients with distal occlusion complicated by dental crowding changes during permanent occlusion. It was found that in clenching according to index ACTIV temporal muscles are more active, due to the insufficient activity of masticatory muscles. It is noteworthy that functional muscle symmetry (SIM TА/MM index) during rest in patients with distal occlusion was significantly lower than in those with physiological occlusion.

The results of the investigation give grounds to assert that during orthodontic treatment of patients with distal occlusion complicated by dental crowding in permanent dentition it is necessary to use complex techniques, ie orthodontic appliance therapy should be accompanied by massage and mio-gymnastics to improve functional state of temporal and masticatory muscles.

REFERENCES

1. Dmytrenko M., Nesterenko O. Results of follow-up study of occlusion state in Ukrainian schoolchildren. J Stoma. 2016; 69(6):725-728.

2. Dmytrenko M., Kuroiedowa V. Electromyographic characteristic of orbicularis oris in patients with  dental crowding in permanent occlusion. J Wiad Lek. 2016;69(3 pt 2):462-464.

3. Drohomyretska M.S., Hrechnova Yu.V. [Importance of Electromyographic Study of Dentoalveolar System at Various Stages of Orthodontic Treatment]. New Technologies in Orthodontics: Coll. Sc.Papers. First Ukrainian Orthodontic Congress. Kyiv, 2013; 37-40. Ukranian.

4. Ferrario V.F., Sforza C., Miani A. Jr. et al. Electromyographic activity of human masticatory muscles in normal young people. Statistical evaluation of reference values for clinical applications. Oral. Rehabil. 1993;20(3):271–280.

5. Smaglyuk L. V., Fetisova G. V., Remali Anas [State of Bioelectrical Activity of Muscles of Maxillofacial Area in Patients of 6-9 years old with Malocclusion and Heredetary Anamnesis]. The Medical and Ecological Problems. 2011; 5/6:149. Ukranian.

6. Кrechina Е. К., Pogabalo I.V., Verzilova M.V. et al. [Correlation between Bioelectrical Activity of Maxillofacial Area Muscles, Postural Status and Masticatory Function in Patient with Distal Occlusion during Temporal Dentition]. Dentistry. 2013;4:57–61. Russian.

ADDRESS FOR CORRESPONDENCE

Maryna I. Dmytrenko

Department of Orthodontics

Higher State Educational Establishment of Ukraine

“Ukrainian Medical Stomatological Academy”

Shevhenko str. 23, 36011, Poltava, Ukraine

tel: +380506324055

e-mail: dmitrenko25@ukr.net

Received: 28.10.2017

Accepted: 03.04.2018

Table І. Average values (M ± m) and variation coefficient (Cv) of BP oscillation amplitude (microwave) of temporal (TA) and masticatory (ММ) muscles in experimental groups

Muscle

Group

І

ІІ

Distal occlusion with dental crowding

Physiological occlusion

During rest position

 

right

33,75 ± 3,17

26,87 ± 3,24

left

25,76± 4,13

26,38 ± 3,17

average

29,75± 2,44

26,63 ± 2,89

ММ

 

right

23,09± 3,79

20,28 ± 3,59

left

21,54±3,03

20,03 ± 3,27

average

22,32± 2,51

20,15 ± 3,00

During clenching

 

right

680,60 ± 118,26*

750 ± 93,13

left

622,42± 100,05

653,41 ± 67,61

average

651,51± 97,50

701,89 ± 71,29

ММ

   

right

346,63± 35,16

510,01 ± 67,67

left

466,54± 78,27

557,89 ± 68,27

average

406,58± 51,82

533,95 ± 64,26

Note:*Significant difference between the indices of the I and II groups at P<0,05.

Table ІІ. EMG indices of temporal (TA) and masticatory muscles (MM) in groups (M ± m)

Index, %

Group

І

ІІ

Distal occlusion complicated by dental crowding

Physiological occlusion

During rest position

ASIM

15,29± 8,59

5,39 ± 5,41

МASIM

27,05± 4,90*

15,32 ± 2,53

MSIM

72,95± 4,90*

90,52± 3,00

ASIM

3,00± 8,67

–4,47 ± 4,76

МASIM

24,49±4,00

12,02 ± 2,97

SIM

75,51± 4,00

87,98 ± 2,97

ASIM TА/MМ

11,54± 6,18*

1,01 ± 3,92

МASIM TА/MМ

19,99±3,40

11,15 ± 1,28

SIM TА/MМ

80,01±3,40*

88,85 ± 1,28

АCTIV

–15,42± 6,26

–14,13 ± 2,06

TORS

11,54± 6,18

5,18 ± 3,47

During clenching

ASIM

3,66± 6,30

5,39 ± 5,41

МASIM

16,26± 3,82

15,32 ± 2,53

SIM

83,74± 3,82

84,68 ± 2,53

ASIM

-7,63 ± 7,63

–4,47 ± 4,76

МASIM

21,46± 4,24

12,02 ± 2,97

SIM

78,54± 4,24

87,98 ± 2,97

ASIM TА/MМ

-2,23± 4,90

1,01 ± 3,92

МASIM TА/MМ

13,80±2,33

11,15 ± 1,28

SIM TА/MМ

86,20±2,33

88,85 ± 1,28

АCTIV

-20,73± 8,01

–14,13 ± 2,06

TORS

2,04 ± 5,23

5,18 ± 3,47

Note: * – Significant difference between the indixes of the I and II groups at P<0,05.