1.6.2.01

Connection of Facial Osteoreceptive Fields Irritation with Change ofStomathognathic System Biomechani sg

Mära ApineLatvian Institute of Experirnental and Clinical Medicine

4, O.VAcieSa Str., Rigu LV-1004, Latvia

Abstracf Facial osteorreceptive fields mechano-

receptors activation causes change of mandibularkinetics by kraniomandibular disfunction.Activation of temporal bone arqus zygomaticusand mandible bone tuberositas masseterica me-chanoreceptors elicits reflex relaxation of masse-

teric muscles and incrrease of bite force.

INTRODUCTION

Masseteric muscles and facial sceleton bones

are inervated by n.trigeminus. Our previous workshows the interaction of elicited afferentation and

motion process of masseteric muscles by trige-minal system pathology.

The aim of this study was to offer a scheme offacial irritation points by masseteric muscles reflexcontraction at kraniomandibular disfunction,change of mandibular kinetics during the

relaxation of masseteric muscles by mechano-

receptive irritation of face osteoreceptive fields,as well as gnathodynamometrie and their results

before and after mechanoreceptive irritation offacial osteoreceptive fields.

MATERIAL AND METHOD

l6 kraniomandibular disfunction (KMD)patients (12 female and 4 ma\e, 13 -70 years old)were observed. Patients were subjected to clinicalexamination and gnatho-dynamometrie beforeand after mechanoreceptive irritation (MI) offacial osteoreceptive fields (FOF).

There was also a control group (12 female and

4 male 13-70 years old) which was observed,

Medical & Biological Engineering & Computing Vol. 34, Supplement 1, Part 1, 1996The 1Oth Nordic-Baltic Conference on Biomedical Engineering, June 9-13, 1996, Tampere, Finland

clinical examined and gnathodynamometriedwithout MI of FOF.

Thus a scheme of MI points was produced,

considering place of origo et insertio muscles

masseterici (at tuberositas masseterica mandi-

bulae and processus zygomaticus ossis tempo-

ralis) and muscles pterygoidei mediale (at tubero-

sitas masseterica mandibulae) with preserving the

general fulfilment of methodic [l(Fig.l)

Fig. 1. Scheme of mechanoreceptive irritationpoints.

I. processus zygomaticus ossis temporalispoints of MI.II. tuberositas masseterica mandibulae points ofMI.

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By bilateral reflex contraction of musclesmasseterici et pterygoidei mediale (trismus) MIwas performed on the both side of face(on arquszygomaticus ossis temporalis dx. et sin., tubero-sitas masseterica dx. et sin.), but by unilateralreflex contraction of muscles pterygoidei medialeand the teeth row deviation from the sagittalplane, MI was made on the contralateral side offace (on tuberositas masseterica)

Gnathodynamometrie (modification of mecha-nogramme [2]) was registered in such a way: ourpatient was sitting in a chair, the force detector ofthe gnathodynamometer [2] was placed betweenthe investigated upper and lower 5-6 teeth, andthe patient was asked to bite his jaws as strong aspossible (without annoying feelings) and thenrelax before and after the course of MI.

MI was ca:ried out two times a weak. Thenumber of irritations was individual (the courseof MI was 10-15 times) and was related with thespeed of recovery.

RESULTS

Mechanoreceptive irritation of facial osteore-ceptive fields cause return to normal state of theteeth rows relations. Already after the first per-formance of MI there was observed change ofmandibular kinetics in KMD patients. After bila-teral MI on the tuberositas masseterica et arquszygomaticus points, there was observed decreaseof trismus, but after unilateral MI on the tubero-sitas masseterica points there was observeddecrease of teeth rows deviation from the sagittalplane. The speed of disappearance of mandiblekinetics disturbs was individual and correlateswith increase of teeth bite force.

There was observed increase of massetericmuscles bite force from l2O + 4N till 150 + 0N(p<0,05). In the control group those changes ofmandible kinetics and increase of bite force werenot observed.

DISCUSSION

The results of this investigation shows thatmechanoreceptive irritation of facial osteore-ceptive fields in kraniomandibular disfunction,patients elicited reflex relaxation of massetericmuscles, that cause return of mandible kinetics tonormal state and increase of teeth bite force.

The reflex contraction of muscles aresupposed to be trigered either by a painful lesionof the affected muscles ore by a disfunction ofneibouring joint and the increase in musclestensin is brought through the y loop [3J. In accor-dance with t4l there is close connection ofmuscles and bone system function and afferen-tation from bone mechanoreceptors causes thechange of motoneurons activity that results aschange of muscles motive parametres. It wassuggested that MI of FOF by KMD patients maybe decreases activity of y loop, with connectionwith decrease of nucleus mesencephalicusmotoneurones activity. Afferent signals alreadyin early degenerativ-dystrophic changes of bonetissue decrease force of muscles isometricalcontraction, but irritation of bone mechanore-ceptors normalise functional state of bone nerveends, improve osteogenesis and increase muscleforce [4]. It relates also, to facial sceleton bones.

REFERENCES

[1] G.Yankovsky, Osteoreception. Riga: Science,1982.(Russ).

[2] USSR Auth. Certif. n.o.1554894 .

t3l P.Berberich, U.Hoheisel, S.Mense andP.Skeppar, "Fine muscles afferent fibres andinflammation: changes in discharge behavioraland influence on gamma-motoneurones" . In Fineafferent fibers and pain . Edited by R.F. Schmidt,H.G. Schaible and C.Vahle-Hinz. Weinheim:VCH Verlagsgesellschaft, 1987, pp.l 65-175.I4l A.Mertens, Functional interaction betweenmuscle and skeletal system. Riga: Science, 1986.(Russ).

Medical & Biological Engineering & Computing Vol. 34, Supplement 1, part 1, 1996The 1Oth Nordic-Baltic Conference on Biomedical Engineering, June g-13, 1996, Tampere, Finland330