Treatment outcome of extraoral implants in the craniofacial region

Oculopalpebral prosthesis prototype design using the additive manufacturing technique: A case study

Three-dimensional (3D) printing technology has advanced for applications in the field of reconstructive surgery. This study reports the application of a comprehensive methodology to obtain an anatomical model, using computed tomography and 3D printing, to treat a patient with cancer who designed a prototype oculopalpebral prosthesis for the reconstruction of the affected area of the face (left eye). A personalized prototype was obtained, which adapted to the face of the person, and improved the aesthetics and quality of life. The applied techniques helped to make definitive prostheses using materials that could be permanent. The training and tests carried out in this study favored the understanding and assimilation of the technology and the possibility of applying it to patients in need of facial prosthetic rehabilitation.

9-year follow up on maxillofacial implant-supported framework designed to accommodate childhood growth

This clinical report focuses on the challenges and solutions for a child subjected to craniofacial trauma from a wild hyena biting off his nose and anterior maxilla. Unique considerations in prosthodontics and biomedical engineering were required based on future craniofacial growth and development of the child. The physical requirement of a maximum retentive prosthesis for an active, athletic child required unique engineering designs and executions. The sequence of treatment and prosthesis fabrication are detailed. The patient has been followed for nine years without physiologic complications and only minor prosthodontic complications. This article is protected by copyright. All rights reserved.

An implant-retained auricular prosthesis complicated by a modified temporal bone resection

A patient underwent a modified temporal bone resection and total auriculectomy to remove a sebaceous carcinoma arising from the tragus of the right auricle that extended into the external auditory meatus. Because the tumor extended into the temporal bone, the osseous sites originally selected for immediate placement of the craniofacial implants were resected and no longer available. Subsequently, after an appropriate period of healing, implants were placed into the residual temporal bone, considerably more superior and posterior to the external auditory meatus such that they emerged through hair-bearing skin. The purpose of this report was to describe the fabrication of an implant-retained auricular prosthesis with implants in suboptimal positions. Challenges included optimization of the stability and retention of the prosthesis, effectively managing the prosthetic space without compromising the esthetic outcome, providing adequate hygiene access for the implant connecting bar, and maintaining the health of the peri-implant tissues when the implant emerged through hair-bearing skin.

Lobe of sound: prosthetic rehabilitation of partial auriculectomy defect

Loss of facial organs in an individual may be due to congenital anomalies or acquired causes. The missing parts of the face like ear, eyes and nose are considered as maxillofacial defects that can be rehabilitated by a prosthesis and/or cosmetic surgeries. This frontier of science has developed into a more reliable and predictable process due to the ever-increasing development of materials and equipments used in this procedure. The fabrication of an ear prosthesis is considered by many prosthetists to be one of the most difficult replacements in maxillofacial reconstruction. The severe undercuts and pronounced convolutions of the ear present a challenge in simulating a naturally proportioned prosthesis. Proper assessment of the disfigured facial organs and a feasible approach to rehabilitating them has for long been the target of clinical maxillofacial prosthodontics. This report describes a simple and engrossing technique to rehabilitate a patient with a partial auricular defect in the most aesthetic and economical manner using medical-grade room temperature vulcanising silicone.

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.

Retention systems for extraoral maxillofacial prosthetic implants: a critical review

We describe the techniques available for retention of implant-supported prostheses: bar-clips, O-rings, and magnets. We present reported preferences and, although this is limited by the heterogeneity of methods used and patients studied, we hope we have identified the best retention systems for maxillofacial prosthetic implants. If practitioners know the advantages and disadvantages of each system, they can choose the most natural and comfortable prosthesis. We searched the PubMed and Scopus databases, and restricted our search to papers published 2001-13. MeSH terms used were Maxillofacial prosthesis and Craniofacial prosthesis OR Craniofacial prostheses. We found a total of 2630 papers, and after duplicates had been removed we analysed the rest and found 25 papers for review. Of these, 12 were excluded because they were case reports or non-systematic reviews. Of the remaining 13, 10 described group analyses and seemed appropriate to find practitioner's choices, as cited in the abstract (n=1611 prostheses). Three papers did not mention the type of prosthetic connection used, so were excluded. The most popular choices for different conditions were analysed, though the sites and retention systems were not specified in all 10 papers. The bar-clip system was the most used in auricular (6/10 papers) and nasal prostheses (4/10). For the orbital region, 6/10 favoured magnets. Non-osseointegrated mechanical or adhesive retention techniques are the least expensive and have no contraindications. When osseointegrated implants are possible, each facial region has a favoured system. The choice of system is influenced by two factors: standard practice and the abilities of the maxillofacial surgeon and maxillofacial prosthetist.

Osseointegration and implant stability of extraoral implants in Göttingen minipigs after irradiation

OBJECTIVES

The aim of this study was to compare the influence of implant surface treatment and irradiation dose on implant stability and osseointegration of 144 extraoral implants in irradiated frontal bone of minipigs.

MATERIAL AND METHODS

144 implants with 3 different surface treatments (machined, etched and HAVD-coated) were implanted in the frontal bone of 16 Göttingen minipigs. Three groups of four pigs received radiation with equivalent doses of 25, 50 and 70 Gy, and one group served as control. Resonance frequency analysis (RFA) was performed recording Implant Stability Quotients (ISQ) at implant placement and 3 months thereafter. Removal torque was measured whilst removing specific implants after 3 months. In addition, the bone-to-implant contact (BIC) was analyzed.

RESULTS

Evaluation of ISQ, BIC-values showed no significant difference between the different surface treatments in irradiated and non-irradiated bone. Removal torque revealed statistically significant differences between machined and HAVD-coated implants in the irradiated bone.

CONCLUSIONS

Implant stability and osseointegration, based on Removal Torque showed significant higher results for the HAVD-coated implants. No significant difference was observed between the irradiated and non-irradiated animals. This study shows that HAVD-coated extraoral implants can potentially be used for craniofacial rehabilitation in non-irradiated and irradiated bone.

A systematic comparison of bar-clips versus magnets

STATEMENT OF PROBLEM

Currently, which type of suprastructure is preferred when fabricating implant-retained craniofacial prostheses is unknown.

PURPOSE

The purpose of this systematic review was to identify the best retention system (bar-clips versus magnets) for implant-retained craniofacial prostheses.

MATERIAL AND METHODS

This systematic review was conducted and reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. A systematic search of Medline/PubMed and Web of Science databases for clinical trials was conducted on implant-retained craniofacial prostheses published between 2005 and 2015. English-language studies that directly compared different types of retention systems or presented information on implant survival, periimplant soft tissue reactions, and prosthetic complications were included. Nonclinical studies were excluded to eliminate bias.

RESULTS

A total to 173 studies were identified, of which 10 satisfied the inclusion criteria. In total, 492 participants were included in these studies. Four selected studies displayed detailed information with regard to the number of implant failures according to the retention system. As reported, 29 (18.2%) of 159 implants with magnets failed, whereas 25 (31.6%) of 79 implants with bars failed. Overall auricular superstructures showed the highest survival (99.08%). In addition, 55.4% of all participants in the selected studies showed grade 0 of periimplant soft tissue reactions.

CONCLUSIONS

A systematic search for clinical studies resulted in few studies with a short-term follow-up and small number of participants. The limited data collected indicated that magnets show fewer complications than bar superstructures; however, no hard conclusions could be drawn. Further research, preferably in the form of clinical trials, is needed to validate these findings.

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.

Treatment Outcome of the Transfacial Titanium Epiplating System for Total Nasal Defects

BACKGROUND

Malignant tumors are the most frequent reason for acquired defects of the nose. Bone-anchored craniofacial prostheses represent a secure, uncomplicated, and cosmetically acceptable rehabilitative alternative to surgical reconstruction. The aim of this study was to determine a potential benefit of the Titanium Epiplating System (Fa. Medicon, Tuttlingen, Germany) as a grouped implant system in the anatomically difficult nasal region with limited bone supply.

METHODS

Patients with complete nasal defects who received a transfacial Titanium Epiplating System between January of 2009 and December of 2013 for nasal prostheses were included. The Epiplating titanium plates are specially adapted to the nasal region and were modified individually. Implant survival, periimplantitis, clinical course, and risk factors for implant survival were assessed retrospectively, including univariate statistics.

RESULTS

Fifty-three patients were included in this study. At the time of last follow-up, 51 of 53 Epiplating systems (96.2 percent) were stable in situ. One titanium plate had to be renewed because of a traumatic accident and one plate had to be removed because of disease recurrence. Periimplantitis occurred in 7.5 percent and could be treated successfully by either local or systemic antibiotic therapy without any loss of stability in bone anchorage. Only smoking significantly increased the risk of periimplantitis (p = 0.013), whereas age, irradiation, chemotherapy, and immunosuppression did not influence the outcome of therapy. The median healing time with use of the Titanium Epiplating System was 3.6 ± 2.7 months.

CONCLUSIONS

The Titanium Epiplating System is a safe and uncomplicated system for bone-anchored retention of nasal prostheses. Good aesthetic results can be achieved.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Soft Tissue Response and Survival of Extraoral Implants: A Long-Term Follow-up

Maxillofacial defects may be reconstructed by plastic surgery or treated by prosthetic mean rehabilitation. In case of large defects, prosthetic rehabilitation rather than surgical reconstruction is preferred due to the insufficient esthetic results of surgical interventions. However, retention of the craniofacial prosthesis is a great problem despite the satisfactory esthetic results. With the presentation of extraoral implants, the retention of maxillofacial prostheses was improved, and osseointegrated craniofacial implants have become indispensable for retention and stability. However, there are conflicting results regarding the success rates of osseointegrated implants used at the craniofacial region. A total of 24 patients with 64 implants (30 in auricular region of 13 patients, 24 in nasal region of 8 patients, and 10 in orbital region of 3 patients) ranging in age from 16 to 83 years (mean age = 45.45 years) were evaluated. One patient among 13 patients (1/13) has lost his implants in the auricular area, 1 patient among 8 patients (1/8) lost his implants, and 1 patient among 3 patients (1/3) has lost all of her implants. Peri-implant soft tissue response was evaluated for a 60-month period and a total of 654 visits/sites recorded. Grade 0 (no irritation) was present in 72.8% (476/654) of the visits/sites. Grade 1 (slight redness) was observed for 18.8% (123/654). Grade 2 (red and slightly moist tissue) was scored in 6.9% (45/654). Grade 3 (red and slightly moist tissue with granulation) was noted in 1.5% (10/654) and grade 4 (infection) could not be found. Ossseointegrated implants provide reasonable support and show successful results when used with maxillofacial prostheses.

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.

Stability Testing of a Wide Bone-Anchored Device after Surgery without Skin Thinning

Objective. To longitudinally follow the osseointegration using Resonance Frequency Analysis (RFA) for different lengths of abutment on a new wide bone-anchored implant, introduced with the non-skin thinning surgical technique. Study Design. A single-center, prospective 1 year study following adults with bone-anchored hearing implants. Materials and Methods. Implantation was performed and followed for a minimum of 1 year. All patients were operated on according to the tissue preserving technique. A 4.5 mm wide fixture (Oticon Medical) with varying abutments (9 to 12 mm) was used and RFA was tested 1 week, 7 weeks, 6 months, and 12 months later. Implant Stability Quotient (ISQ), was measured from 1 to 100. Stability was compared to a group of patients (N = 7) implanted with another brand (Cochlear BI400) of 4.5 mm fixtures. Results. All 10 adults concluded the study. None of the participants lost their implant during the test period indicating a good anchoring of abutments to the wide fixture tested. Stability testing was shown to vary depending on abutment length and time after surgery and with higher values for shorter abutments and increasing values over the first period of time. One patient changed the abutment from 12 to 9 mm and another from a 9 to a 12 during the year. No severe skin problems, numbness around the implant, or cosmetic problems arose. Conclusion. After 1 year of follow-up, combination of a wide fixture implant and the non-skin thinning surgical technique indicates a safe procedure with good stability and no abutment losses.

Quality of implant anchored craniofacial and intraoral prostheses: patient's evaluation

BACKGROUNDS

Bone-anchored prostheses have become a major issue in the rehabilitation of patients with facial defects. The objective of this study was to analyze how patients perceived the quality of implant-retained orbit, ear, nose, maxilla, or partial face prosthesis.

METHODS

The patients' satisfaction from implant-retained prostheses usage was evaluated by a group of 30 patients with various facial defects. The survey referred exclusively to oncologic patients. Surveyors were classified basing on their age, sex, and defect localization, and their satisfaction was assessed by standardized questionnaire with 6-grade scale.

RESULTS

Overall, acknowledging some weaknesses, such as reduced condition of surrounding soft tissue and necessity to enhance hygienic care, most of the patients assessed their prostheses as "good" emphasizing excellent mechanical retention and high wearing comfort. More detailed analysis revealed itemized outcome: (i) auricular prosthesis was indicated as the most comfortable solution by the patients; (ii) women and patients older than 55 years were more satisfied with the treatment results than men and patients younger than 55 years; and (iii) implant-retained prostheses were generally rated better than conventional adhesive-retained solutions.

CONCLUSIONS

The results of the study proved that generally implants improve the satisfaction of patients with craniofacial prostheses. However, the actual level of satisfaction depends, to a large extent, on the defect's localization, sex, and age of the patient.

Extraoral implants in the rehabilitation of craniofacial defects: implant and prosthesis survival rates and peri-implant soft tissue evaluation

PURPOSE

Few reports have evaluated cumulative survival rates of extraoral rehabilitation and peri-implant soft tissue reaction at long-term follow-up. The objective of this study was to evaluate implant and prosthesis survival rates and the soft tissue reactions around the extraoral implants used to support craniofacial prostheses.

MATERIALS AND METHODS

A retrospective study was performed of patients who received implants for craniofacial rehabilitation from 2003 to 2010. Two outcome variables were considered: implant and prosthetic success. The following predictor variables were recorded: gender, age, implant placement location, number and size of implants, irradiation status in the treated field, date of prosthesis delivery, soft tissue response, and date of last follow-up. A statistical model was used to estimate survival rates and associated confidence intervals. We randomly selected 1 implant per patient for analysis. Data were analyzed using the Kaplan-Meier method and log-rank test to compare survival curves.

RESULTS

A total of 150 titanium implants were placed in 56 patients. The 2-year overall implant survival rates were 94.1% for auricular implants, 90.9% for nasal implants, 100% for orbital implants, and 100% for complex midfacial implants (P = .585). The implant survival rates were 100% for implants placed in irradiated patients and 94.4% for those placed in nonirradiated patients (P = .324). The 2-year overall prosthesis survival rates were 100% for auricular implants, 90.0% for nasal implants, 92.3% for orbital implants, and 100% for complex midfacial implants (P = .363). The evaluation of the peri-implant soft tissue response showed that 15 patients (26.7%) had a grade 0 soft tissue reaction, 30 (53.5%) had grade 1, 6 (10.7%) had grade 2, and 5 (8.9%) had grade 3.

CONCLUSIONS

From this study, it was concluded that craniofacial rehabilitation with extraoral implants is a safe, reliable, and predictable method to restore the patient's normal appearance.