Impression Technique for a Patient with Maxillary Defect - A Case Report
0

Dr. Sejal Shah

Abstract

In a society that values appearance, those who exhibit malformed parts of the face, neck and oral cavity may become less socially acceptable. Rehabilitation of the maxillofacial patient into society requires a broad knowledge of prosthodontics, plus the capacity for compassionate patient management. Oral cancer is now a common occurrence requiring partial or complete maxillectomy. The most common oral complication of the current pandemic Covid is mucormycosis, and treatment requires partial resection of the maxilla. Rehabilitation starts with a good impression of the maxillary defect. Maxillofacial defects are always unique, and require special impression techniques, one of which is explained in this case report.

Key words-Obturator, Impression

Introduction

The cleft palate is an opening in the hard and/or soft palate. It may be genetic due to improper union of the maxillary process and the median nasal process during the second month of intrauterine development. It may also be acquired and the most common causes for maxillary defects are trauma, disease, pathological changes, genetics, surgical intervention, syndrome associated, drugs, radiation burns etc.

Primary Objectives

In the total rehabilitation of the maxillectomy patient, there are two primary objectives:

  1. To restore the functions of mastication, deglutition and speech.
  2. To achieve normal oro – facial appearance.

Impression Technique

  • The small defects should be blocked out with moist cotton or gauze (gauze or cotton should be lubricated with vaseline or petrolatum).
  • Larger defects with gross undercuts should be packed with 4 x 4 inch gauze squares, it should be readily retrieved and they should be shoved into the defect.
  • With time, the dentist will acquire clinical judgment with regard to which areas need blocking out prior to impressions.
Also read:  Dental Insurance in India: Tooth Matters

Step by Step Procedure

  • Preliminary impressions
  • Primary cast
  • Fabrication of special tray
  • Final impression
  • Obtaining the master cast

Preliminary Impressions

The intra – oral defect can be seen in Fig. 1.

FIGURE 1Pre operativeIntra oralview bb4dec838b0dd5c99fa366cc137210b6 800
Fig 1 – Pre-operative intraoral view

Material of choice for preliminary or primary impression – irreversible hydrocolloid impression material i.e alginate or impression compound (Fig. 2).

FIGURE
Fig 2 – Maxillary primary impression

Diagnostic Casts

Diagnostic cast was made with plaster of Paris in a regular manner (Fig. 3).

FIGURE 3PrimaryCastinPlasterofParis 96faafa959b66a533060f41843d1a7dd 800
Fig 3 – Primary cast in plaster of Paris

Fabrication of Special Tray

Any undercuts in the primary cast should be blocked by using utility wax. Wax spacer adapted on the cast including the defect area (Fig. 4). Tissue stops were included to help proper application of forces. Special try was fabricated (Fig. 5).

FIGURE 4SpacerDesignandBlockout 7b8f1bed8d30c771f7159a120d410a63 800
Fig 4 – Spacer Design & Blockout
FIGURE 5AcrylicSpecialTray b198267fe0ad7288fb478b1290b79e2a 800
Fig 5 – Acrylic Special Tray

Border Molding

Border molding the posterior and lateral area of a maxillectomy requires that the patient go through certain head and mandibular movements.

Movements to be Performed

The patient has to open and close the mouth, move the mandible from side to side, turn the head from side to side, place the chin down to the chest, move the head from side to side, and extends the head backward after seating the tray.

Border Molding

Special tray was checked in patient’s mouth and the space between the tray and tissues was examined. Tray adhesive was applied to increase the adhesion between the tray and additional silicone and border molding was performed (Fig. 6).

Also read:  PEEK: A Prodigious Material in Dentistry
FIGURE 6BorderMoulding 41459bcd7a2ad168c8db864ebfe67ead 800
Fig 6 – Border molding

Final Impressions

Spacer was removed and wash impression was performed except in defect area. Putty material was mixed and secured with gauge piece and placed in patient defect area and all head moment are recorded. After recording the defect area putty was attached to special tray (Fig. 7).

FIGURE 7FinalImpressionwithLightbodyimpressionmaterial 0455fa3b4ab3fb48e93cb8b065c9e45a 800
Fig 7 – Final impression with light body impression material

Master Casts

Master cast was poured using dental stone (Fig. 8).

FIGURE 8MastercastinDentalStone 02d115800a306ce6bcc86cf75a53c620 800
Fig 8 – Master cast in dental stone

After making the impression with the right technique, the sequential steps of complete denture construction were followed as usual. (Figure – 9).

FIGURE 9Post operativeviewwithProstheses 24cd5c0c90e1b642ab6bbaf6eb02cd5e 800
Fig 9 – Post operative view with prostheses

Discussion

Prosthodontic management of palatal defects has been employed for many years. Ambroise Pare probably was the first to use artificial means to close a palatal defect – as early as the 1500's. The early obturators were used to close congenital rather than acquired defects. The early objectives of treatment were artificial closure of the defect and adequate retention of the artificial closure. The ingenious designs of the early pioneers accomplished these objectives. As time progressed, newer and better concepts of obturators evolved.

The basic objectives of prosthodontic therapy include a comfortable, cosmetically acceptable prosthesis that restores the impaired physiologic activities of speech, deglutition and mastication. The most important objective of prosthodontic care, as DeVan stated, our objective should be “The perpetual preservation of what remains rather than the meticulous restoration of what is missing.” This principle is most important in the treatment of the maxillary defect patient.

Also read:  International Women’s Day: Meet 10 of India’s Dental Trailblazers

The discomfort caused by hard resin presents another problem. Popular maxillofacial prosthodontist, Dr. Albert has almost completely abandoned the use of rigid prosthetic materials for making obturators. Among the synthetized materials, he found silicon-rubber components to be the most effective. They are easy to produce and function well. However, for the permanent obturator, maxillofacial prosthodontist Brown states, “. . . heat-cured methyl methacrylate resin still remains the material of choice for tissue compatibility, environmental resistance and ease of adjustment.”

Summary

A thorough knowledge of what is normal is a must for the dentist to understand the acquired defects with which he interacts. It is important that the clinician become familiar with a technique and master it. It must always be remembered, and patient must be so counselled before treatment, that the clinician can only try to provide alternative means of what the patient has lost, and how successful that alternative will be, depends upon the patient’s ability to accept the defect and to adapt to an alternative environment.

“Not mere survival from disease alone, but a return to a normal functioning life” is a must.

610e0d09965bc bpfull
Dr Sejal Narendrakumar Shah
Dr. Sejal Narendrakumar Shah, (MDS)is a prosthodontist & oral implantologist,practicing in Mumbai. She has earned many awards, accolades and authored various articles in national & international dental magazines.

    Nano-Diamonds: A Ray Of Hope Against Antibiotic Resistance.

    Previous article

    Surgical Management Of Mandibular Dentigerous Cyst – A Case Report

    Next article

    Comments

    Leave a reply

    Your email address will not be published. Required fields are marked *

    You may also like