NASAL PROSTHESIS SUPPORTED WITH SELF-TAPPING IMPLANTS WITH BIOACTIVE SURFACE – A CASE REPORT

INTRODUCTION

Osseointegrated implants have had a dramatic impact on patient acceptance of facial prostheses. Patients like the security, comfort, and convenience of implant-retained prostheses, benefits that are not attainable with earlier methods of retention (1, 2). Surgeons have come to appreciate the reduced need for numerous complex surgical reconstructive procedures in many of these patients. For large defects, a multidisciplinary approach is recommended, combining flap reconstruction and implant-retained prosthetic rehabilitation to achieve optimal results (3, 4).

Earlier reports have shown that osseointegrated implants are not uniformly successful, and the failure rates in some patients/sites are quite high. The failures and complications appear to be site specific and radiation and time dependent (5, 6).

The choice between surgical reconstruction and prosthetic restoration of large facial defects remains a difficult one and depends on the size and etiology of the defect, as well as on the wishes of the patient. Development and application of osseointegrated implants to facial defects has, in part, changed patient perceptions of facial prosthetics. Implants allow convenient and secure positioning of the prosthesis, leading to greater patient acceptance.

CASE REPORT

A 63-year-old woman with diagnosis recurrent basocellular cancer of the nose was treated. After ablation of the nose, external radiotherapy and chemotherapy were applied. The full oncological treatment was completed in 2007. The patient had no other systemic problems; she was in good health and had suffered from no serious injuries. She had only experienced the usual childhood diseases, and she did not suffer from any allergies. She did not drink alcohol, smoke or take drugs. The surgical and prosthodontic rehabilitation was started 1 year after termination of the treatment.

In the margin of the postoperative defect three intraosseal dental implants with acid and alkali-treated, hydrophilic surface were inserted (STI-BIO-C, Lasak Ltd., Czech Republic). The operation was performed under general anesthesia with nasotracheal intubation. The primary implant site for nasal defects was the piriform ridge at the base of the nose (two implants – left and right, diameter 3.7 mm and length 10 mm ). The radix was also used as an implant site (diameter 3.7 mm and length 8 mm) for our defect; the primary consideration was the degree of pneumatization of the frontal sinus and the quantity of the overlying bone (Fig. 1). The operation lasted 65 minutes and was free from any complications. Healing of the wound proceeded without inflammatory process. Lincomycin (600 mg p.o.) provided an antibiotic covering. On day four after the operation the patient was dismissed in good condition. Six months after implant placement and the healing period the prosthetic reconstruction began. The patient was screened with a control tomogram (Fig. 2). Magnetic attachments (Steco-titanmagnetic-system 3.7 mm, Impladent, Lasak Ltd., Czech Republic), (Fig. 3) were inserted, and nasal epithesis was prepared as follows.

The one-stage technique of the nasal prosthesis with freestanding abutments and magnet retention was used. The direction of emergence of the abutments was examined. It was desirable to have the retentive elements oriented to pull the prosthesis onto the skin surface. To achieve this and to have the retentive components in a position that was convenient to manipulate, hand-made cantilevered abutments were selected (Fig. 4) (Impladent, Lasak Ltd., Czech Republic). A try-on set of custom-made magnetic abutments were available to allow for selection of the appropriate cantilever angle.

The impression of the defect is recorded as a sectional alginate impression (Kromopan 100 – Lascod). The impression was boxed and poured in the stone. Baseplate wax (Fig. 5) was used to form the borders of the designed acrylic-resin substructure (Fig. 6). The wax pattern (wax up) was prepared and evaluated on the patient and finalized.

A stone overcast was constructed. The wax was boiled out and the surfaces of the cast and overcast were painted with separating medium and autopolymerizing acrylic resin (Duracryl – Dental) (see Fig. 6). The acrylic resin was cured in a pressure pot. Prosthesis form, coloration and texture were finished with special silicone (Multisil Epithetic/Bredent/) (Fig. 7). The completed nose was pumiced and polished (Fig. 8).

A magnet was attached to the face of the abutment (Fig. 9). The interface between the abutment and the keeper was recorded with a one-phase silicone (Fig. 10). The magnets were connected to the abutments (Fig. 10–13).

DISCUSSION

Fukuda et al. (7) surveyed patients with nasal or paranasal malignanttumors who underwent anterior craniofacial resection. Current status of long-surviving patients and theirsubjective assessment of the surgical treatment were also evaluated through questionnaires. The resultsshowed that all patients complained of unsightly appearance, and when the patients themselves evaluatedtheir condition after surgery, 63% were dissatisfied. Sometimes the results of the plastic surgery are not sufficient to restore the entire volume of the nose (8). We have confirmed that craniofacial implants improve the stability of the prosthesis and provide ease of use without eyeglasses or adhesives.

The benefits of magnetic implant insertion and nasal prosthesis are as follows. The optimal stability of the prosthesis guarantees thepatient recovery of his social life.Two magnetic attachments are used in the framework positioned in the maxilla. The last one remains as an emergency alternative in case of glabella failure. The oral implants, with bioactive surface properties, offer a wider surface for osteointegration (9) and faster healing capacity (10). Magnet attachments ensure better surface stability than ball attachments (11) while not obstructing or making epithesis handling more difficult for the patient.

CONCLUSION

Facial prosthesis using three dental implants is a method of choice in replacement of missing hard and soft orofacial tissues. Prosthesis form, coloration, and texture must be as indiscernible as possible from the surrounding natural tissues. Rehabilitation efforts can only be successful when patients can appear in public without fear of attracting unwanted attention. Dental implants prosthesis support gives the patient confidence in society.

Acknowledgement: The study was supported by project IGA MZČR 9991-4.

Address for correspondence:

Tatjana Dostalova, M.D., D.Sc., MBA
Department of Paediatric Stomatology
2^nd Medical Faculty, Charles University
V Úvalu 84
150 00 Prague 5
Czech Republic
E-mail: Tatjana.Dostalova@fnmotol.cz