Implant-retained nasal prosthesis for reconstruction of large rhinectomy defects: the Salisbury experience

Abstract

The authors report their experience with 34 patients who had large full thickness nasal defects reconstructed with an implant-retained prosthesis. Their technique of modifying post-rhinectomy defects is described and factors influencing implant success are evaluated. 111 implants were placed to retain a nasal prosthesis. Age, sex and tumour histology did not affect the outcome. Smoking, extent of rhinectomy, use of radiotherapy (pre- and post-implant), hyperbaric oxygen, length and location of the implant and type of retention (bar/magnets) influenced implant success. The overall success rate was 89% (99/111); 94% in patients who did not receive radiotherapy and 86% in those who did. The prosthesis was in place in all patients (100%) at the time of last follow up. Post-rhinectomy defect modification enables adequate access for safe placement of long implants with good primary stability and helps the maintenance of good hygiene (further enhanced by the use of skin grafts). The authors think implant-retained prosthesis is a reliable option for reconstructing large full thickness rhinectomy defects. They suggest their technique of modifying the defect, use of long implants and magnets for retention is responsible for the high success rate of implants used to retain a nasal prosthesis.

Reconstruction of nasal defects has a long history dating back almost 2000 years to the days of Sushruta, the famous Indian surgeon, and the pharaohs. Partial thickness defects can be managed very satisfactorily by surgery. Full thickness defects can be reconstructed by surgery or a prosthesis. Reconstruction of large, full thickness defects of the nose following ablative oncological surgery remains a challenge, despite recent advances in surgical reconstruction techniques. The necessity to restore the complex three-dimensional shape of the nose, with a satisfactory cover, lining and appropriate support often requires staged procedures and the availability of healthy local tissue. Even with the use of free tissue transfer, the final aesthetic outcome leaves much to be desired, especially when adjacent tissue has also been lost. The risk of recurrence and the use of radiotherapy often add further challenges to the reconstruction.

When the decision has been made to undertake a prosthetic reconstruction, the prosthesis can be retained by an implant or other methods. The use of tissue adhesives to retain an implant can be associated with contact dermatitis and allergic reactions, loss of adhesion and dislodgement, and unsightly bulky prosthetic edges . Attaching the prosthesis to spectacles overcomes these shortcomings, but means the glasses cannot be removed independently of the prosthesis.

An implant-retained prosthesis overcomes these limitations and gives the patient the security of a stable prosthesis . Increasing experience with implant-retained craniofacial prostheses has allowed satisfactory reconstruction of isolated auricular, orbital and nasal defects in addition to complex defects involving multiple craniofacial structures . This experience has been largely limited to specialized centres in Canada, Sweden and the USA and the available literature is often in the form of multi-institutional studies evaluating implant-retained prostheses used to reconstruct multiple sites .

Experience of reconstructing large, full thickness nasal defects with implant-retained prosthesis is limited and has mainly referred to the overall success or failure rates of these implants . A literature review documented 128 implants placed in the nasal skeleton to retain nasal prostheses of which 23 were placed within a field of radiotherapy. The success rates were 60–100% in patients who had not received radiotherapy and 50–100% in patients who had received radiotherapy . Little information is available on the technical aspects of the procedure or the factors influencing the success of these implants and the retained prosthesis. The authors present their experience with 34 patients, who received 111 implants to reconstruct large, full thickness rhinectomy defects and they evaluate the multiple factors that could influence the success of these implants and the retained prosthesis.

Patients and methods

The authors undertook a retrospective analysis of all patients who had had a rhinectomy defect reconstructed with an implant-retained prosthesis in the authors’ hospital. The data analysed included the demographic data and smoking habits of the patients, the pathology necessitating the rhinectomy and factors influencing the survival of the implant and the prosthesis, which encompassed the extent of rhinectomy, use of radiotherapy and hyperbaric oxygen, length and location of the implant, one- or two-stage procedure and type of retention. The implant was considered to have failed if it was removed or lost for any reason and the prosthesis was counted as a failure if it was not retained by the implants. The significance of the various factors was analysed using Fisher’s exact test and was considered significant if p < 0.05. In view of the multiple potential confounding factors and relatively small number of critical events and patients, these finding can be considered spurious. The results will be primarily presented in a descriptive format, documenting the frequency of occurrence. The surgical technique of preparing the rhinectomy defect prior to the placement of implants is described.

Defect modification

Following excision of the tumour with adequate margins ( Figs 1 and 2 ), the residual defect is modified to help retain the prosthesis. The prominent bony lip of the piriform aperture is trimmed and the anterior part of the nasal septum and the inferior turbinates is removed ( Fig. 3 ). This provides a flat base for the prosthesis and allows access for instrumentation and maintenance of hygiene. Implants of sufficient length to obtain bi-cortical purchase are placed in the nasal floor, taking care to avoid the tooth roots. A split skin graft, shaped like an elephant ( Fig. 4 ) is then laid on the nasal floor, piriform rims and around the implants, taking care not to distort the upper lip and cheeks ( Fig. 5 ). This provides an immobile base for the prosthesis, which is free of secretions. This is followed by construction and delivery of the prosthesis ( Fig. 6 ).

Fig. 1
Clinical picture of nasal tumour.

Fig. 2
Unmodified post-rhinectomy defect.

Fig. 3
Areas of defect modification.

Fig. 4
Elephant’ shaped skin graft.

Fig. 5
Postoperative appearance of the implants in situ .

Fig. 6
Nasal prosthesis in situ .

Results

34 patients had 111 implants placed to retain a nasal prosthesis ( Table 1 ). The age range was 46–86 years with a mean of 67 years. The male to female ratio was 2.4:1. 16 patients had a basal cell carcinoma, 15 had a squamous cell carcinoma and three a salivary tumour. The mean follow up period was 31 months, with a range of 4–108 months.

Table 1
Analysis of factors influencing the outcome of implants used to retain a nasal prosthesis.
Parameters No. of patients No. of implants No. of failures Percentages p -Value
Age
Below 59 years 4 12 1 8%
60–69 years 13 41 6 15%
70–79 years 8 27 2 7%
Above 80 years 9 31 3 10% 0.8699
Sex
Female 10 25 3 12%
Male 24 86 9 11% >0.9999
Histology
Salivary tumour 3 9 1 11%
BCC 16 57 6 11%
SCC 15 45 5 11% 1.000
Type of rhinectomy
Partial 1 2 1 50%
Standard (soft tissue) 15 30 1 3%
Total (soft and hard tissue) 10 31 3 10%
Extended 8 48 7 15% 0.1229
Smoking
Yes (+ex) 20 67 9 13%
No 14 44 3 7%
Ex (alone) 3 12 2 17% 0.4058
Radiotherapy (preoperative)
No 16 48 3 6%
Yes 15 49 8 16% 0.1991
Radiotherapy (postoperative)
Yes 3 + 1 a 18 2 11% NA
Hyperbaric oxygen
RT + HBO 13 43 7 16%
RT − HBO 2 6 1 17% >0.9999
Length of implant
3–7 mm 26 5 19%
10 mm 44 3 7%
13 mm 21 2 10%
15 mm 3 0 0%
18 mm 3 0 0%
40, 45, 50 mm 4 0 0%
Unsure 10 2 20% 0.6056
Location of implant
Floor of nose 57 4 7%
Glabella 14 1 7%
Maxilla 18 3 17%
Zygoma 8 1 13%
Orbital rims 14 3 21% 0.3869
Stages
One stage 16 52 3 6%
Two stages 18 59 9 15% 0.1337
Retention
Magnets 32 102 9 9%
Bar 2 9 3 33% 0.0564
Nose only 71 6 9%
No RT 34 0 0%
RT − preoperative 31 6 19%
RT postoperative 6 0 0%
RT + HBO 25 5 20%
RT − HBO 6 1 17% 0.0325
Total 34 111 12 11% NA
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Feb 8, 2018 | Posted by in Oral and Maxillofacial Surgery | Comments Off on Implant-retained nasal prosthesis for reconstruction of large rhinectomy defects: the Salisbury experience
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