MYOFACIAL PAIN DYSFUNCTION SYNDROME

SHAHBAZ ALAMSATYABAMA DENTAL COLLEGE

MPDS is a pain disorder, in which unilateral pain is referred from the trigger points in myofacial structures, to the muscles of head and neck.

DEFINITION

These are localized tender areas within taut bands of skeletal muscles when stimulated by macro- micro traumatic episodes

TRIGGER POINTS

30 % of population suffers

Female- male ratio is 3:1

Age group – 15-40 years

EPIDEMIOLOGY

ETIOLOGY

All Etiological factors leads to micro or macro trauma to musculoskeletal system leading to muscle spasm

This hyper tonicity may lead to muscle fatigue and accumulation of metabolic byproducts such as Lactic acid, prostaglandins, bradykinins, histamine

The accumulation of these chemical pain mediators, lowers pain threshold to mechanical and chemical stimuli leading to MPDS.

PATHOPHYSIOLOGY

Spasm of lateral pterygoid muscle

Spasm of elevator muscles

Spasm of lateral pterygoid and elevator muscles

CLASSIFICATION

Cardinal symptoms of MPDS

CLINICAL FEATURES

Pain or discomfort

Limited motion of the jaw

Joint noises- Clicking, snapping

Tenderness to palpation of the muscles of mastication

Associated symptoms of MPDS

NeurologicTingling

NumbnessBlurred vision

TwitchesLacrimation

OtologicTinnitusEar painDizzinessVertigo

Diminished hearing

Gastrointestinal tractNausea

VomitingDiarrhea

ConstipationDry mouth

MusculoskeletalFatigueTension

TirednessWeaknessJoint pain

Various masticatory muscles and their clinical effects

Laskins Diagnostic criteria

Four cardinal signs

• Unilateral pain• Muscles tenderness• Clicking- clicking or popping noise in the TMJ• Limitation of jaw movement

Negative characteristics

• No radiographic evidence• No tenderness in TMJ area on palpation via the external

auditory meatus

Diagnosis

1.Articular or TMJ function

2.Palpation for tenderness

3.Grading of click or crepitation

Physical Examination

Range of motion

a)Vertical opening – check for hypo mobility( Normal range for an adult is 40-50

mm)

b) Deviation while opening and closing

c) Protrusive deviation and movement – normal range is 10mm

d) Lateral excursion – Normal range is 10mm

Palpation for tenderness

The area responsive to palpation are called

“Trigger points”.

The muscles are palpated bilaterally and

simultaneously with firm but gentle pressure

lasting for 1-2 mins

Middle finger is used for palpation

For larger area adjacent fingers can be used.

Grading of click

• Early , immediate or wide open zones of

condylar excursion are noted

• It should be noted whether the sound is on

opening , closing or both.

Resistance test

Opening Protrusion Left excursion Right excursion

MANAGEMENT

Goal of treatment :• 1.TrP inactivation• 2.Prevention of recurrence• 3.Correction of perpetuating factors

Prognosis depends on :• Correct diagnosis• Early and proper treatment• Acute MPS good prognosis

• To educate and empower patients to understand and manage the symptoms of MPDS and to regain and maintain normal function with as much independence as possible

Follow – 7 R’s for occlusal rehabilitation

1.Remove - extract2.Reshape - grind3.Reposition - orthodontia4.Restore – conservative dentistry5.Replace - prosthesis6.Reconstruct – TMJ surgery7.Regulate – control habit and symptoms

Pharmacotherapy

Pain control – mainly used analgesics Salicylates (aspirin 2 tabs 0.3-

0.6 gm/4 hourly)

Tranquilizers – provides calming effect in anxiety state and relieves

tension, fear and produces a sense of well being (Diazepam 2-5 mg at

bedtime)

Antidepressants – these are mood elevators like lithium carbonate

and caffeine

Sedatives & Hypnotics – reduces excitement and produces sleep

PHYSICAL MEDICATION

Tongue exercise Mouth opening exerciseHot packs

Ultrasound

Massage

Electrical stimulation (TENS)

ANESTHESIA•Muscle and fascia (trigger point)

•TMJ (Intracapsular and extracapsular) – 0.5 ml of 0.5% Xylocaine in conjugation with injection of hydrocortisone

•Refrigerated spray – vapocoolant spray, such as ethyl chloride or fluoromethane is used to reduce muscle spasm

Other therapies

Hypnotherapy – here patient cooperation is must and should follow hypnotist suggestions. It provides muscle relaxation

Acupuncture – it is a simple, effective and conservative pain control modality. But this therapy is used only to give relief from pain and will not remove basic cause.

Surgery – various surgical procedures like eminectomy, zygomectomy, menisectomy, high condylectomy are advocated.