Nasal prosthesis for a patient with xeroderma pigmentosum.

Acquired facial defects caused by extirpation of neoplasms, congenital malformations or traumatic injury results in a huge functional, cosmetic and psychological handicap in those patients. These defects can be restored by facial prosthesis using different materials and retention methods to achieve a lifelike appearance and function. This clinical report describes a treatment schedule using silicone nasal prosthesis, which is mechanically retained for a patient who has undergone a partial rhinectomy due to basal cell carcinoma of the nose. The prosthesis was made to restore the esthetic appearance of patient with a mechanically retained design using a spectacle glass frame without any prosthetic adhesives so that the patient is more comfortable and confident to resume daily activities.

Xeroderma pigmentosum (XP) is a rare autosomal recessive disorder characterized by a defect of deoxyribonucleic acid (DNA)-repair occurring during ultraviolet (UV)-induced damage. The disease is quite complex and different subsets of abnormalities in the DNA-repair system may occur during the course of the disease. Thus, patients with XP have a decreased cutaneous immune surveillance, which results in an increased risk of UV-induced skin tumors such as basal cell carcinoma (BCC), squamous cell carcinoma, actinic keratoses, atypical moles and malignant melanoma, all associated with severe photoaging commonly seen at the early age.[1]

XP occurs with an estimated frequency of 1:25,000 in United States and somehow more common in Japan. Its incidence in the Indian context is not significant.[2] This is a case report of XP presenting with BCC of the nose treated through a partial rhinectomy, the bridge of the nose, including the nasal bones was included in the resection, followed by post-operative radiotherapy.

The first historically documented evidence comes from 16th century, when the French Surgeon Ambroise Paré describes the first nasal prosthesis from gold, silver, which were held to the face by a string tied around the head. In late 19th century, Claude Martin conceived an idea of an immediate prosthesis using tissue excised from the maxilla and mandible as a template for fabricating complex appliances. In 20th century while the quality-of-life like craniofacial prostheses was considerably improved with the introduction of silicone materials, their retention, which is important for esthetics, function and comfort, was obtained with anatomic undercuts, adhesives and attachment to maxillary obturators, prosthetic connections to endosseous implants.[34]

When suitable conditions are provided, mechanical retention obtained by anatomic undercuts is the most advantageous. The advantages of this prosthesis are that the techniques is noninvasive, tissue tolerant, esthetic, comfortable to use and easy to fabricate and clean. In addition, this prosthesis is often preferred by the patients because the weight and the cost of such prosthesis are low. The presence of moisture, mobile soft-tissues and lack of stable tissue support are disadvantages affecting the retention in such prosthesis.[456]

The purpose of this case report is to provide a modality of treatment for partial rhinectomy case using a definitive nasal prosthesis made of silicone and retained by eye glasses.

Case Report

A 15-year-old girl was referred to the department of prosthodontics from Otorhinolaryngology Department, Chennai medical College, for nasal prosthesis. Patient had undergone a partial rhinectomy as a treatment for BCC of nose. The bridge of the nose and nasal bone was included in the resection [Figure 1]. Surgical reconstruction and various prosthetic rehabilitation techniques were discussed, general medical complexity of surgical reconstruction such as inward tissue constriction, collapse of tissues and patient refusal to undergo surgery lead to this method of rehabilitation.

Figure 1

Profile view

A silicone nasal prosthesis retained using a spectacle glass frame was decided as a treatment plan. The boundary for the impression was outlined on patient face. Necessary precautions taken and a moist gauze was packed to prevent the flow of the material in to the undesired areas of defect, an impression was taken of the defect together with the adjacent tissue, using an irreversible hydrocolloid impression material (Algitex; DPI, Mumbai).

The impression was removed, poured with type III dental stone (Kala Stone; Kala Bhai Pvt. Ltd., India). The model prosthesis was sculpted on the facial cast with no. 2 wax (MDM Corporation, India) [Figure 2]. The wax pattern was then tried on to the patient face, it was checked especially in the border areas and the pattern was reviewed to assess the potential areas for prosthesis retention. Tissue texture and relevant contours were evaluated on the face of the patient [Figure 3].

Figure 2

Fabrication

Figure 3

Patient with model

Flasking and dewaxing done. Patients skin tone was used as a guide to match the prosthesis. The silicone material mixed with intrinsic colors on a ceramic slab and compared with patient's skin color tone. The mold was then packed with the prepared material and processed according to the manufacturer instructions. After deflasking, the prosthesis was evaluated on the patient and some extrinsic water resistant coloration was added to make the prosthesis more realistic [Figure 4].

Figure 4

Patient with prosthesis

After the final contouring and matching, the prosthesis was attached to the glass frames [Figure 5]. The eye glasses were used to maximize the retention and to improve the esthetic appearance of the patient. The placement of the prosthesis was demonstrated to patient. Patient was scheduled for the first post-insertion adjustment 1 day after the insertion to ensure the health of the tissues and to relieve any pressure areas on the tissues. Patient was then asked to come for recall visit once in every 3 months for evaluation of prosthesis and observation of any recurrence.

Figure 5

Final profile view with prosthesis

Discussion

Facial defects can result from trauma, treatment of neoplasm's or congenital malformations. The choice between the surgical reconstruction and prosthetic restoration of large defects remains a difficult one and depends on the size and etiology of the defect as well as on the wish and condition of the patient. Restoration of facial defects is a difficult challenge for both surgeon and prosthodontist. As both surgical reconstruction and prosthodontic restorations have distinct limitations.

The surgeons are limited by the availability of tissue, the compromised local vascular bed, the need for the periodic visual inspection of an oncological defect and physical condition of the patient. Whereas, the prosthodontist is limited by inadequate materials available for facial restorations, movable tissue beds, difficulty in retaining large prosthesis and patient capability to accept the final outcome. When surgical reconstruction not possible for patients with facial deformities, the choice of treatment is prosthetic rehabilitation.[78]

Most facial prostheses like nasal prostheses are retained with adhesives and mechanisms including anatomic undercuts, external attachments and attachment to maxillary obturators, magnets and prosthetic connections to endosseous implants. Each of these methods has its own advantages and disadvantages.

Mechanical retention obtained by anatomic undercuts is the most advantageous. However, the presence of moisture, mobile soft-tissues or lack of stable tissue support affects the retention. In this case, the eye glasses were used to augment the adhesive retention and to achieve a lifelike appearance.

Various biomaterials such as polymethyl methacrylate (PMMA) and silicone have been used for facial reconstruction. PMMA resin is one of the oldest materials to be used in maxillofacial prosthodontics for fabricating temporary prostheses, but can also be used for making definitive prostheses.[9] Silicone materials are most widely used for construction of facial prosthesis, the common problems associated with silicone are rapid degradation of elastomers and color dexterity, deterioration due to environmental exposure to UV light, air pollution and temperature, tearing of margins, microbial growth due to the porous nature of silicones and short durability.[89] Silicones were preferred for this patient because of the following advantages:

Light weight

Lifelike appearance[410]

Softness compatible to tissue

Translucent

Ease of intrinsic and extrinsic coloring with commercially available colorants

Ease of mold fabrication, processing and reusable molds

Non allergic and non-toxic

Dimensionally stable[11]

Because of its soft flexible nature it can engage minor tissue undercuts to enhance retention and stability.

The purpose of the nasal prostheses was to improve the cosmetics and esthetics. In this case report, a silicone nasal prosthesis was fabricated for a patient with partial nasal defect caused due to BCC of the nose, which made him psychologically more comfortable. Furthermore, innovation in the field of maxillofacial prosthetics will lead for a better comfortability not only the operator, but also for the patient.