FABRICATION OF A CLEAR POLY-METHYL METHACRYLATE ACRYLIC RESIN NASAL STENT FOR A PATIENT TREATED FOR DEVIATED NASAL SEPTUM: A CASE REPORT

ABSTRACT

Internal defects of nose result from congenital abnormalities, trauma, tumour excision, and complications of cosmetic or airway enhancement procedures. One of the most common reasons for noncosmetic nose surgery is a deviated nasal septum and thus producing breathing difficulty through nose. But post-surgical scar contracture may lead to the collapse of airway. Thus provision of a nasal stent for the patient is indicated during the initial period of healing to maintain the patency and contours on the nasal cavity during the healing period and thus preventing the stenosis or collaspe of the airway. This article presents a technique of fabricating a clear polymethyl methacrylate acrylic resin nasal stent for a patient treated surgically for deviated nasal; septum. KeyWords:- Nasal stent, deviated nasal septum, clear resin, airway

INTRODUCTION
Internal defects of nose result from congenital abnormalities, trauma, tumour excision, and complications of cosmetic or airway enhancement procedures 1 and otorhinolaryngologists frequently solicit the support of dentists to make intranasal prosthesis, splints and stents. A prosthesis is defined as an artificial replacement for an absent body part; a splint maintains hard and/or soft tissue in a predetermined position; and a stent is a mold for supporting a soft tissue or bony graft during healing 2. Intra-nasal stents are used in several ways with reconstructive surgery 3. Nasal stents may be used after the graft procedures in order to maintain the patency of airways during the healing period and prevent the stenosis or collapse of airway due to post-surgical scar contracture. Stents may also be used for patients surgically treated for nasal tumours or obstructions by their surgical excision. This will again maintain the airway and minimized contracture during healing period.
One of the most common reasons for noncosmetic nose surgery is a deviated nasal septum and thus producing breathing difficulty through nose. A deviated nasal septum may be corrected via septoplasty with or without rhinoplasty. But, post-surgically, excessive scar contracture may cause the internal airway to collapse or stenotic, producing an aesthetic as well as functional problem. Thus to minimize the cicatricial contraction, nasal stents should be inserted as soon as possible after the surgery in order to maintain the patency of nasal cavity during the initial healing period after surgery and should be worn by the patient for several months during the healing period 4.
A technique of for the fabrication of a clear acrylic resin nasal stent to maintain the patency of nasal cavity during the initial healing period after surgery has been presented in this article.
CLINICAL REPORT
A 20 year old female patient was referred to the department of Prosthodontics and Crown & bridge, Government Dental College, Rohtak, India by an otorhinolaryngologist. She had undergone septoplasty for the correction of deviated nasal septum which was causing her a difficulty in breathing through the nose. She was refereed for the fabrication of a nasal stent in order to maintain the patency as well as the contour of nasal cavity during the initial healing period. [Figure 1 and Figure 2]. The patient was in good general health. There was no significant medical finding. The intra-oral examination revealed congenitally missing mandibular central incisors. It was decided to fabricate a nasal stent with clear heat-polymerized methyl methacrylate acrylic resin for her.

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Fig-1	Fig-2

PROCEDURE
1. Firstly, a cake of mod¬eling plastic impression compound (Pinnacle; Dental Products of India Ltd) was softened in a water bath and molded into a cylindrical shape and inserted into both the nasal cavities to record their impression 5. and a band of plastic impression compound was used to connect the impressions of both nasal cavities.[Figure 3] A Plastic impression com¬pound was used as it was stiff, moldable, and did not droop as a result of gravity 6. And the modeling plastic impression compound was lubricated with petroleum jelly before inserting into nasal cavities in order to prevent its adherence to the internal nasal mucosa, and it was meticulously inserted, taking care not to damage the nasal mucosa.

Fig-3

2. A frame of the plastic modeling compound was made around the nose to confine and support the irreversible hydrocolloid impression material (Alfina) which was used to make the external impression of the nose. [Figure 4 and Figure 5]

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Fig-4	Fig-5

3. Stapler pins were embedded into the alginate impression before its final set and the impression was reinforced with dental plaster. Stapler pins provided retention and mechanical locking of plaster over the alginate impression. [Figure 6 and Figure 7].

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Fig-6	Fig-7

4. The patient was requested to wrinkle his facial muscles to permit easy removal of the completed impression. And after removal the impression was immediately placed in cold water to prevent distortion caused by heat dissipation of the plaster backing. Then, the impression was poured in Die stone, Type-III, and vibrated carefully to avoid bubble formation. [Figure 8]

Fig-8

5. When the stone cast was set, it was trimmed as desired. [Figure 9]

Fig-9

6. Wax-up of the prosthesis was done on the obtained cast and was tried-in on the patient in order to verify the fit and contours. 2 stainless steel orthodontic wires (21-gauge) were incorporated before packing, to provide strength to the final prosthesis. And finally the tried wax pattern was processed in heat polymerizing clear acrylic resin (DPI-heatcure; Dental Products of India Ltd).

7. A hole (3 mm diameter) on each side through each nasal cavity projection was drilled to provide the airway for breathing through nose.

8. Finally the completed nasal stent was adequately finished and polished to make it comfortable for the patient and prevent injury to nasal mucosa. [Figure 10]

Fig-10

9. The prosthesis was delivered to the patient and she was asked to wear it continuously (even during sleeping), and removing only for cleaning. [Figure 11]
10. The device was long enough to cover only the cartilaginous pyramid of the nose. The prosthesis had a bridge across the nasal columella to connect both sides to prevent its accidental posterior displacement and possible inhalation.

Fig-11

DISCUSSION

The stent was fabricated to maintain the patency of the airway and also provides support to the soft tissues of the nose and thus maintain the contours of the nose. The design of stent included a bridge across the columella in order to connect the two nasal cavities and also to prevent the possible posterior displacement of the stent during inhalation. The stainless steel wires incorporated in the nasal stent provided strength to the bridge across the columela that connects the two nasal cavities. Poly Methyl methacrylate acrylic resin was chosen as the material for the fabrication of nasal stent because it is easy to work with, economical, hygienic, and well tolerated by the patient and durable. Moreover, it was aesthetically made from clear acrylic resin. However its use is limited because of its rigidity. The 3mm holes drilled through the nasal stent resulted in reduced entry of air through the nose and enabling a gentle nasal breathing and thus providing rest for the nasal cilia and also including reversibility of nasal mucosa 7.
The advantages of nasal stent fabrication with this technique are that it is cost-effective, tissue tolerant, aesthetic to patient, comfortable to use, easy to fabricate and easy to clean by the patient.

SUMMARY

A technique for fabrication of clear poly-methyl methacrylate acrylic resin nasal stent for a patient who underwent a corrective surgery for a deviated nasal septum has been presented in this article. The nasal stent was fabricated after the surgery and for the maintenance of the patency of nasal cavity and to provide support to the nasal soft tissues during the initial period of healing.

BIBLIOGRAPHY

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