Presentation:

Scenario:

A patient has been suffering from bell's palsy on the right side for the last one year visits your clinic as he wants a denture. How this condition would affect your treatment protocol??

By :

Sara Sajjad

Final Year B.D.S

Department of Prosthodontics

SBDC Gandhara University

What is BELL'S PALSY??

Named after CHARLES BELL

(Well known for his studies on the nervous system and the brain)

In the 19th century he discovered that lesions of the 7th cranial nerve i.e the facial nerve cause facial paralysis.

Types:

A). Temporary

Most common Lasts for weeks to months only Recovers but can reoccur Causes includes:

viral infections, ear infections, high B.P. Diabetes, headaches, trauma etc.

B). Permanent

Less common Considered when lasts for more than 9 months Causes includes

birth trauma, major damage to the nerve due to trauma, laceration etc.

Clinical features

Facial asymmetry Eyebrow droop Inability to close eye Uncontrolled tearing Drooping of corner of mouth Loss of forehead & nasolabial

folds Lips not held tightly together:

Difficulty keeping food in mouth

Difficulty in keeping food on occlusal table

Other signs and symptoms

Pain or discomfort in jaw Headache Dizziness Dryness of eyes Loss of taste Dryness of mouth and Impaired speech Difficulty in eating and drinking Ringing in the ear Hypersensitivity to sound

The facial muscles which are affected include:

Occipitofrontalis Procerus Nasalis muscle Depressor septi nasi Orbicularis oculi Corrugator supercilii Depressor supercilii Auricular muscles (anterior, superior, posterior)

Facial muscles that affect denture stability

Buccinator Orbicularis oris Levator anguli oris Depressor anguli oris Mentalis

BUCCINATOR MUSCLE:

Importance in recording

Maxilla:

Buccal frenum Buccal vestibule

Mandible:

Buccal frenum Buccal vestibule Retromylohyoid fossa Retromolar pad

ORBICULAROUS ORIS:

Importance in recording

Maxilla:

Labial vestibule Buccal frenum

Mandible:

Labial frenum

LEVATOR ANGULI ORIS:

Importance in recording

Maxilla:

Buccal frenum

Mandible:

No any

DEPRESSOR ANGULI ORIS:

Importance in recording

Maxilla:

No any

Mandible:

Buccal frenum

MENTALIS:

Importance in recording

Maxilla:

No any

Mandible:

Labial frenum

Central VS Peripheral Facial Nerve Palsy

Facial paralysis is due to a lesion of the facial motor nucleus or of the nerve

A lower motor neuron lesion:

All the muscles of the same side of the face are affected. (There may also be inadequate lacrimal or salivary secretion, or a localized taste deficit, depending on the exact location of the lesion.)

An upper motor neuron lesion:

Affects only the lower half of the contra-lateral side of the face

Important Note

Neuro-muscular function and coordination are foundation for successful and stable dentures Failure to diagnose importance of flange contour and teeth position in facial paralysis patients

often leads to unstable dentures In unilateral facial paralysis patient, it is essential to record neutral zone because of imbalanced

forces generated by unaffected and affected side causing instability in dentures

What is neutral zone??

Also known as “zone of minimal conflict” or “Dead Space” The zone where the cheeks, lips and tongue are in maximal harmony with the dentures That is the teeth in the denture must occupy the same position as there natural predecessors The inward forces by the lips and cheeks should be balanced by the outward forces by the

tongue

Initial & Final Impression Recording

Conventional technique for making primary and final impressions is followed except that excessive material is incorporated on the right side that is the affected side

Temporary Denture Base

A stable denture base is constructed on master cast

Recording Neutral Zone

After initial adjustment of occusal plane according to aesthetics and phonetics, compound rim was softened and patient was encouraged to do functional movements such as swallowing, sucking, pursing lips

Thus the polished surface of denture base was contoured by functions of the tongue and action and tonus of affected and unaffected lips and cheek

Recording Neutral zone Mandibular record base with modeling plastic impression compound moulded to patient’s neutral zone

A plaster index was fabricated to duplicate

the contour of polished surface in trial denture

Occlusal wax Rims

Midline placed in the middle of the oral cavity rather than the facial midline

Teeth Set-up

Teeth are arranged according to the neutral zone matrix Non anatomic posterior teeth are used to establish the centric occlusion

Some improvement of the appearance can be achieved by:

1. Placing the mesio-incisal point in the middle of the mouth rather than the middle of the face

2. keep the cant of the occlusal plane on the right side a little low for incisal show

Buccal sulcus support

Placing buccal support on the right side to reduce the facial droop This will also help reduce the accumulation of food in the affected buccal vestibule

Finally

Dentures are processed and inserted Pateint's satisfaction

Instructions

Patient is educated about oral and denture hygiene maintenance

References

Designing Full Dentures by Watt and MacGregor Prosthodontic treatment of edentulous patients by Zarb-Bolender Jaypee text book of Prosthodontics by Nallaswamy Prosthodontic management of complete edentulous patients with neuromuscular disorders -

Case reports (Suresh S Vipul Asopa) Pictures from e-net and books