Extra-oral implants: insertion per- or post-ablation?

Outcome of implants placed to retain craniofacial prostheses - A retrospective cohort study with a follow-up of up to 30 years

OBJECTIVES

To retrospectively assess the treatment outcomes of endosseous implants placed to retain craniofacial prostheses.

MATERIAL AND METHODS

Patients with craniofacial defects resulting from congenital disease, trauma, or oncologic treatment had implant retained prostheses placed in the mastoid, orbital, or nasal region and then assessed over a period of up to 30 years. Implant survival rates were calculated with the Kaplan-Meier method. Clinical assessments consisted of scoring skin reactions under the prosthesis and the peri-implant skin reactions. Possible risk factors for implant loss were identified. Patient satisfaction was evaluated using a 10-point VAS-scale.

RESULTS

A total of 525 implants placed in 201 patients were included. The median follow up was 71 months (IQR 28-174 months). Implants placed in the mastoid and nasal region showed the highest overall implant survival rates (10-year implant survival rates of 93.7% and 92.5%, respectively), while the orbital implants had the lowest overall survival rate (84.2%). Radiotherapy was a significant risk factor for implant loss (HR 3.14, p < 0.001). No differences in implant loss were found between pre- and post-operative radiotherapy (p = 0.89). Soft tissue problems were not frequently encountered, and the patients were highly satisfied with their implant-retained prosthesis.

CONCLUSION

Implants used to retain craniofacial prostheses have high survival and patient satisfaction rates and can thus be considered as a predictable treatment option. Radiation is the most important risk factor for implant loss.

Orbital exenteration: an updated review with perspectives

Orbital exenteration is a radical and disfiguring surgery mainly performed in specialized tertiary care centers. Orbital exenteration has long been considered the treatment of choice for managing periocular tumors invading the orbit or primary orbital malignancies. Over the past decades, attention has been directed toward reducing the perioperative morbidity by developing new surgical devices and new strategies and promoting cosmetic rehabilitation by providing adequate facial prostheses. Despite these advances, several studies have questioned the role of orbital exenteration in improving overall survival. The last decade has been marked by the emergence of a new paradigm: the "eye-sparing" strategies based on conservative surgery with or without adjuvant radiotherapy and/or targeted therapies and immunotherapies. We summarize the data on orbital exenteration, including epidemiology, etiologies, use of surgical ablative and reconstructive techniques, complications, outcomes, and the related controversies.

Survival rate of disk and screw-type implants used for the retention of extraoral prostheses

STATEMENT OF PROBLEM

Implant-supported and implant-retained extraoral prostheses are reliable treatment options for patients with craniofacial defects. They provide stable retention and therefore enhance the patient's appearance and quality of life. Despite studies on survival rates of extraoral implants, little attention has been paid to the design of the implants used to support and retain extraoral prostheses.

PURPOSE

The purpose of this longitudinal clinical study was to assess the long-term survival rate (1 to 12 years, mean 6 years) of 2 different designs of implants (disk: single, double, and triple and screw-type) used for extraoral epithesis anchorage.

MATERIAL AND METHODS

Twenty-six participants with orbital and nasal defects, 10 of whom had had radiation treatment, were included in the study. Disk implants and extraoral (EO) screw implants were used and placed in the periorbital (15 participants) and perinasal regions (11 participants). Data were analyzed by using the Chi-square test and the Fisher Exact test for qualitative variables and the Mann-Whitney U test for comparison of quantitative variables. Implant survival rates were calculated by Kaplan-Meier analysis.

RESULTS

The overall 12-year survival rate of all implants was 90.3% (mean=79 months), with 92.9% for nasal (mean=84 months) and 88.2% for orbital (mean=75 months) implants. Related to the implant design, survival rates were as follows: for single-disk implants, 90.2%; for double disks, 94.6%; for triple disks, 88.3%; and for screw implants, 83.3%. In nonradiated participants, the implant survival rate was 97.6%, and for radiated participants, 76.1%.

CONCLUSIONS

Survival rates for implant-retained craniofacial prostheses are limited. The nasal site seems to be a more predictable implant site than the orbital site, with a higher overall survival rate. Also, implants inserted in radiated tissues have lower survival rates for both anatomic sites, with statistically significantly lower results in the orbital region. The most reliable type of implant among the disk implants used was the double disk in the orbital site and the single disk in the nasal site, which may indicate the advantages of some designs in specific areas.

Implant prognosis in irradiated versus non-irradiated nasal, orbital and auricular sites

The purpose of this systematic review was to evaluate implant survival in irradiated nasal, auricular, orbital sites and to compare them with non-irradiated respective sites. Four electronic databases and seven related journals were searched until December and March 2018, respectively. A total of 7892 articles were identified, 18 of which were included in this review; one non-randomized clinical trial, two prospective cohort, eight retrospective cohort and seven cross-sectional studies. Using the ROBIN-I Cochrane tool for risk assessment, 13 studies were judged at serious, one at moderate and four at critical risk of bias. Thirteen were included in 18 meta-analyses, the results of which showed a significant difference between irradiated and non-irradiated sites, favouring non-irradiated with risk ratio (RR) = 0.93, 95% confidence interval (CI) 0.89-0.97, P=0.001. Comparisons among nasal, auricular and orbital sites revealed no significant differences, whether in irradiated or non-irradiated patients at P<0.05. Hence, it was concluded that, within the limitations of this review, survival of craniofacial implants is negatively affected by radiotherapy, especially in orbital sites. Level of evidence is moderate. Therefore, further prospective cohort studies with calculated sample sizes, restricted or properly managed confounders and no deviations from intended interventions might produce different results.

Reliability and accuracy of skin-supported surgical templates for computer-planned craniofacial implant placement, a comparison between surgical templates: With and without bony fixation

INTRODUCTION

The purpose is to determine the accuracy of guided implant placement in the orbital, nasal, and auricular region using computer-aided designed stereolithographic skin-supported surgical templates with and without bone fixation pins.

MATERIALS AND METHODS

Preoperatively, cone-beam CT (CBCT) and multiple detector computed tomography (MDCT) scans were acquired from 10 cadaver heads, followed by virtual planning of implants in the orbital margin, auricular region and nasal floor. Surgical skin-supported templates were digitally designed to allow flapless implant placement. Fixation pins were used for stabilization comprising half of all templates in predetermined bone areas. The accuracy of the surgical templates was validated by comparing the achieved implant location to its virtual planned implant position by calculating the linear and angular deviations.

RESULTS

Surgical templates with the use of bone fixation pins produced statistically significant greater implant deviations as compared to the non-fixated surgical templates.

CONCLUSION

The results of this study indicate that significant deviation has to be taken into account when placing cranio-maxillofacial implants using skin-supported surgical templates. Surprisingly, the use of bone-fixated pins worsened the accuracy.

Survival and complications of implants to support craniofacial prosthesis: A systematic review

OBJECTIVE

To assess the survival rate of craniofacial implants (CIs) to support facial prosthesis/epithesis and the prevalence of surgical/biological complications based on previously published studies.

METHODS

An electronic search was undertaken in March/2016. Only studies with a minimum of 5 patients were included. Untransformed proportions of implant failures for different regions were calculated. A meta-analysis evaluated the influence of radiotherapy on the failure rates. A meta-regression was performed considering the follow-up period as covariate.

RESULTS

Seventy publications included 2355 patients and 8184 CIs (545 failures). The probability of a failure was 5.5% for all CIs (95%CI 4.5-6.5, P < 0.001), 1.2% for CIs in the auricular region (95%CI 0.8-1.5, P < 0.001), 12.2% for the nasal region (95%CI 9.0-15.5, P = 0.017), and 12.1% for the orbital region (95%CI 9.3-15.0, P < 0.001). Radiotherapy statistically affected the CIs rates (OR 5.80, 95%CI 3.77-8.92, P < 0.00001). There was no statistically significant influence of the follow-up time on the proportion of implant failures (P = 0.814). Soft tissue adverse reactions were the most common complications.

CONCLUSIONS

Implants placed in the auricular region have a lower probability of failure than those in the nasal and orbital regions. Soft tissue adverse reactions were the most common complications. Radiotherapy significantly affected the CIs failure rates.

Osseointegrated implants for orbito-facial prostheses: Preoperative planning tips and intraoperative pearls

PURPOSE

Implant-retained facial prostheses are becoming increasingly sophisticated. We describe our experience with successful implant placement.

METHODS

Retrospective case series. Patients with severe unilateral orbital deformity who underwent socket reconstruction with placement of orbital implants were identified. Data on patient age, gender, mechanism of eye, soft tissue, and bone loss, prior reconstructive surgeries and radiation, and orbital imaging were collected and analyzed.

RESULTS

Four patients (9 implants) between 2010 and 2014, who had osseointegrated implants placed for orbito-facial prostheses were identified. Three were male, one female. Average age was 59 years (range 34-86). Reason for eye loss was trauma in two patients, exenteration for recurrent rhabdomyosarcoma in one patient, and enucleation for retinoblastoma in one patient. All patients had Vistafix® (Gothenburg, Sweden) osseointegrated titanium implants (4 mm) placed in a 2-stage procedure over a span of 3-6 months with subsequent successful prosthesis fitting.

CONCLUSION

Implant-retained orbito-facial prostheses are safe, easy, and reliable. The ideal socket has minimal dead space, robust bone, and soft tissue 4-5 mm in depth. Preoperative planning should consist of: 1) orbit CT; 2) careful clinical exam of the orbital deformity; and, 3) analysis of socket topography. Operative tips for successful implant placement include: 1) 2-3 points of fixation; 2) placement of implants in bone of adequate thickness; and 3) implant placement as a 2-stage rather than 1-stage procedure. There appears to be no difference in outcome in irradiated and non-irradiated sockets in this series, but should be a consideration and discussed with the patient.

Recommendations for implant-retained nasal prostheses after ablative tumor surgery: Minimal surgical aftercare, high implant survival, and satisfied patients

BACKGROUND

Nasal defects resulting from tumor resection are preferably rehabilitated with implant-retained nasal prostheses. Aftercare, clinical outcome of the implants, and patients' satisfaction with implant-retained nasal prostheses were assessed.

METHODS

Twenty-eight consecutive patients needing total rhinectomy because of tumor resection between 1998 and 2013 were treated according to a standardized protocol with 2 implants in the nasal floor. Surgical and prosthetic aftercare was scored using patient records. Finally in 2014, skin reaction, peri-implant bone loss, and patients' satisfaction were assessed in all 13 still living patients.

RESULTS

In total, 56 implants were inserted (median follow-up, 35.1 months; interquartile range [IQR], 8.9-63.3). Implant survival was 96.4%. Implant survival was independent of radiotherapy. Peri-implant skin was healthy and patients' satisfaction high. Longevity of the prostheses was limited.

CONCLUSION

Rehabilitation of nasal defects resulting from total rhinectomy with implant-retained nasal prostheses, according to our protocol, resulted in high patient satisfaction and favorable treatment outcome. © 2015 Wiley Periodicals, Inc. Head Neck 38: E-E, 2016.