Retrospective study of treatment outcomes with implant-retained extraoral prostheses: survival rates and prosthetic complications

Clinical and social success in epithetic ear rehabilitation - Retrospectively evaluating the long-term survival of auricular implants

PURPOSE

The aim of this study was to evaluate existing staging recommendations for peri-implantitis and its applicability for auricular bone anchoring.

MATERIALS AND METHODS

In this cross-sectional study, 44 patients treated with 47 ear epitheses and 128 implants were analyzed over 191.6 months (mean). Peri-implant sulcus depth, sulcus fluid flow rate, and peri-implant skin reaction, as well as cleaning habits and patients' quality of life, were analyzed. Mixed effect linear and mixed effect ordered logistic regression models were used.

RESULTS

Two of the 128 implants were lost (1.6 %). A total of 14.5 % of all patients presented light erythemas, 19.4 % showed stage 2, 4.8 % stage 3, and 12.9 % an acute infection according to Holgers. A correlation between skin reaction and sulcus fluid flow rate was observed, when grouping patients with acute signs of inflammation. Concerning patient satisfaction, 58.1 % of the patients were highly satisfied with their epitheses, 39.5 % very satisfied, and one patient was just satisfied. Younger age correlated with lower satisfaction rates.

CONCLUSION

Implant-retained auricular epitheses are a safe, highly sufficient and satisfying way of extending ear reconstruction. Sulcus depth and skin reaction are quick and valuable assessment tools in auricular implants, but skin reaction alone was clinically insufficient to predict peri-implant pocket inflammation.

Accuracy and resolution of conventional and additively manufactured silicone elastomers as applied in maxillofacial therapies

STATEMENT OF PROBLEM

Silicone elastomers are becoming more readily available for additive manufacturing, which may be advantageous for fabricating maxillofacial prostheses. However, the properties of three-dimensionally (3D) printed silicone as compared with conventionally processed silicone have not been well studied.

PURPOSE

The purpose of this in vitro study was to compare the dimensional accuracy and surface resolution of additively manufactured with conventional room-temperature vulcanized (RTV) silicones.

MATERIAL AND METHODS

A custom aluminum mold was used to generate hand-spatulated specimens (A103 and VerSilTal-50F, n=20). A computer-aided design and computer-aided manufacturing workflow was used to generate additively manufactured specimens (Sil30 and TrueSil, n=20). Digital surface scans of each specimen were recorded; a scan of the mold served as the control. Surface dimensions were measured with a digital metrology software program, while digital overlays were made using a 3D processing software program. The surface resolution of the specimens was assessed by analyzing 4 topographical landmarks (flat surfaces, raised lines, domes, and scribed lines) with a visual qualitative grading scale. The data were analyzed with 1-way analysis of variance, followed by a Student-Newman-Keuls post hoc test (α=.05).

RESULTS

The specimens demonstrated statistical differences in trueness and precision (P<.001). The TrueSil specimens showed the largest deviation in measurements of trueness and precision (up to -1.374%). The other specimens yielded percentage mean differences that were more consistently within the range of the American Dental Association International Organization for Standardization standard for elastomers. The manually fabricated specimens yielded more consistently ideal ratings for resolution than did the additively manufactured ones, with the Sil30 specimens receiving the most Charlie (not clinically acceptable) ratings.

CONCLUSIONS

Numerical differences between each specimen and the control were considered negligible for maxillofacial applications. Notable discrepancies related to the quality of resolution, wherein the benchtop-manufactured specimens consistently generated better results compared with additively manufactured ones. Other factors, such as resiliency, odor, and cost, posed limitations in justifying the use of silicones in a direct-to-print workflow.

Effect of in vivo aging on the surface and electrochemical properties of magnetic attachments used in facial prostheses: A retrieval analysis study

STATEMENT OF PROBLEM

Reasons associated with the failure of facial prosthesis are of major concern and may be associated with deterioration of both elastomeric materials and magnetic attachments. However, the extent of deterioration of these components is unclear.

PURPOSE

The purpose of this in vitro study was to evaluate selected retrieved facial prostheses and provide information regarding the electrochemical characterization of the recovered magnetic attachments.

MATERIAL AND METHODS

Five facial prostheses (RP1, RP2, RP3, RP4, RP5) fabricated at the University of Texas, M.D. Anderson Cancer Center were retrieved following clinical use. The intaglio and external surfaces of the prostheses along with the incorporated magnetic attachments were photographed. The areas with the detected failures on the retrieved prostheses, as well as the recovered magnetic attachments, were evaluated under a reflected light stereomicroscope at ×16 nominal magnification and photographed with a digital camera. Five magnetic attachments recovered from the prostheses (retrieved group RT) were evaluated for degradation of their corrosion resistance after electrochemical testing in artificial sweat solution and were compared with 5 unused magnetic attachments (control group, CT). To identify the elemental composition of the intact magnet surface, 1 specimen from the control group was investigated by X-ray energy dispersive spectroscopy (EDS). Means and standard deviations of the open circuit potential (EOCP), the zero-circuit potential (Ecorr), and Icorr were calculated and statistically analyzed by a t test (α=.05 for all tests).

RESULTS

The main reasons of failure were discoloration, degradation and rupture of the silicone elastomer, marginal misfit, and delamination of the polyurethane sheet. Additional findings were tarnish and discoloration of the magnetic attachments accompanied by considerable smear build-up. EDS results verified the Ni plating of tested magnets. Electrochemical testing revealed that retrieved magnets showed significantly lower OCP (P<.001) and Ecorr (P<.001) but similar Icorr (P=0.083) while the pseudopassivity region of unused magnets vanished in the retrieved group, denoting a degradation of electrochemical properties after clinical use.

CONCLUSIONS

In vivo aging exerts extended degradation on the elastomer part of facial prostheses as well as deterioration of their surface integrity and electrochemical properties.

Accuracy of implant placement using CAD-CAM tooth-supported surgical guides for an auricular prosthesis in vitro

PURPOSE

To evaluate the accuracy of tooth-supported surgical guides used to place implants in auricular prostheses. The accuracy (trueness and precision) of the implant positions was evaluated, and the difference between the surgical guide with and without retention of the external auditory canal (EAC) was compared.

MATERIALS AND METHODS

This study simulated implant placement in vitro for the treatment of right auricle malformation. Surgical guides and other casts were fabricated using additive manufacturing technology. The casts were divided into 2 groups according to the surgical guide, with 10 bone blocks in each group (with or without the EAC plug (Guides 1 and 2)). Three implant positions (Implants 1-3) were prepared for each bone block using surgical guides. Implant positions were registered using light-body silicone impressions combined with optical surface scans to measure the coronal, apical, depth, and angular deviations. Four deviations of trueness and precision were reported as the mean ± standard deviation, which was analyzed by Student's t-test.

RESULTS

Each group of 10 bone blocks with 30 implant positions was successfully prepared and digitally reproduced as implants. The accuracies of implant position with surgical guides were acceptable when compared with the preoperatively planned implant positions. Compared with the Guide 2 group, there was a significant difference in the apical, depth, and angular deviations of Guide 1 group in terms of precision (p = 0.001). There was a significant difference in the depth deviation of Implant 1 (p = 0.028) and apical deviation of Implant 2 (p < 0.001) compared two groups in terms of trueness. In terms of precision, there was a significant difference in the coronal (p = 0.002), apical (p = 0.001), and depth (p < 0.001) deviation of Implant 1; apical (p = 0.036) and angular (p < 0.001) deviation of Implant 2 also existed significant difference; the coronal deviation of Implant 3 (p = 0.018) also existed significant difference. Moreover, the group with the EAC plug showed lower deviation in precision and a smaller volume in the 95% confidence ellipsoid.

CONCLUSION

Both types of tooth-supported surgical guides can provide acceptable accuracy. A surgical guide with an EAC plug was considered to be more precise.

Quality of life and psychological evaluation of patients after anaplastology

A comprehensive questionnaire with 43 questions was designed to evaluate quality of life, based on rehabilitation with a facial prosthesis. Each patient's psychological situation was assessed using the validated questionnaire and associated scales. Different patient groups were compared with each other in terms of questionnaire scores and general data. In total, 76 patients with a prosthesis of the orbit, nose, or ear, or a combination thereof, were included. There was a highly significant difference in overall satisfaction with defect reconstruction via a prosthesis of the ear compared with the orbit and nose (F(3) = 6.511, p = 0.001). Patients with congenital defects showed a significantly higher level of general satisfaction compared with patients with acquired defects (F(2) = 5.795, p = 0.001). Patients who returned to work were significantly more satisfied with their quality of life (T(57) = 2.626, p = 0.011). With regard to improvements to the state-of-the-art prostheses, the majority of patients suggested better retention, more durable colors, make-up possibilities, less noticeable margins, softer materials, and a movable orbital prosthesis. Within the limitations of the study it seems that facial epitheses improved mental wellbeing and increased quality of life among patients with facial defects. Multiple factors, such as type of facial defect, location of residence, and education can have a potential influence on the quality of life of affected patients. However, further studies are needed, since the psychological and social challenges remain.

Effect of ultraviolet protective agents on maxillofacial silicone elastomer, part 1: Color stability after artificial aging

STATEMENT OF PROBLEM

Silicone elastomers have been widely used for rehabilitation of facial defects for more than 50 years. However, color change is the most common problem limiting the service life of facial prostheses. Whether the addition of ultraviolet protectives may enhance color stability of these materials is unclear.

PURPOSE

The purpose of this in vitro study was to investigate the effect of ultraviolet protectives on the color stability of maxillofacial silicones after artificial aging.

MATERIAL AND METHODS

Six color groups (unpigmented, white, yellow, red, blue, and mixed) of addition-type maxillofacial silicone were prepared. Four ultraviolet protectives benzophenone-3, ethylhexyl methoxycinnamate, titanium dioxide, and ethylhexyl salicylate at 0.5% and 1% concentrations by weight were incorporated into the silicone before polymerization. The specimens were artificially aged in an accelerated weathering chamber for 300 and 600 hours and in a thermocycling device. The color change values (E) of the maxillofacial silicones were evaluated. Data were statistically analyzed by using 4-way ANOVA. The differences were compared by the Tukey honestly significant difference test (α=.05).

RESULTS

Benzophenone-3 and ethylhexyl methoxycinnamate protectives did not reduce the ΔE values, and the 1% titanium dioxide groups exhibited lower ΔE values than the 0.5% titanium dioxide groups. Ethylhexyl salicylate protective generally reduced the ΔE values significantly in all color and aging groups when compared with the control groups (P<.05). In all control and ultraviolet protective groups, the highest ΔE values were seen with the red color in 300 and 600 hours of aging. Generally, no significant difference (P>.05) was seen in the ΔE values, which were clinically acceptable among the thermocycled color groups. After 600 hours of accelerated aging, the ΔE values were found to be higher than the values of 300-hour aging.

CONCLUSIONS

Ethylhexyl salicylate protective incorporated into maxillofacial silicones may improve color stability.

A Contemporary Review of the Role of Facial Prostheses in Complex Facial Reconstruction

BACKGROUND

Maxillofacial prostheses provide effective rehabilitation of complex facial defects as alternatives to surgical reconstruction. Although facial prostheses provide aesthetically pleasing reconstructions, multiple barriers exist that prevent their routine clinical use. The accessibility of facial prostheses is limited by the scarce supply of maxillofacial prosthodontists, significant time commitment and number of clinic appointments required of patients during prosthesis fabrication, short lifespan of prostheses, and limited outcomes data.

METHODS

A literature review was completed using PubMed and Embase databases, with search phrases including face and maxillofacial prostheses. Patient cases are included to illustrate the use of facial prostheses to reconstruct complex facial defects.

RESULTS

The clinical use of facial prostheses requires a multidisciplinary team including a reconstructive surgeon, a maxillofacial prosthodontist, and an anaplastologist, if available, to provide patients with aesthetically appropriate facial prostheses. Developing technology including computer-aided design and three-dimensional printing may improve the availability of facial prostheses by eliminating multiple steps during prosthesis fabrication, ultimately decreasing the time required to fabricate a prosthesis. In addition, enhanced materials may improve prosthesis durability. Long-term outcomes data using validated measures is needed to support the continued use of facial prostheses.

CONCLUSIONS

Facial prostheses can be used to reconstruct complex facial defects, and bone-anchored prostheses are associated with high patient satisfaction. Multiple barriers prevent prostheses from being used for facial reconstruction. New technologies to assist the design and fabrication of prostheses, and cost reduction measures, may allow their use in the appropriately selected patient.

Effect of ultraviolet-protective 2-ethylhexyl salicylate incorporation on the mechanical properties of different maxillofacial silicone elastomers

STATEMENT OF PROBLEM

Whether the incorporation of ultraviolet-protective 2-ethylhexyl salicylate (UV-ES) affects the mechanical properties of different maxillofacial silicone elastomers, limiting the service life of facial prostheses, is unclear.

PURPOSE

The purpose of this in vitro study was to examine the mechanical properties of different maxillofacial silicone elastomers incorporating different ratios of UV-ES.

MATERIAL AND METHODS

Three different ratios of UV-ES were incorporated into 3 different types of maxillofacial silicones (M511, TechSil-25, and A-2000), and the mechanical properties of the silicones were investigated. Silicone pigments were added to each silicone type to mimic skin color. Dumbbell-shaped specimens were fabricated for tensile strength, percentage elongation, and hardness measurements, and trouser-shaped specimens for tear strength measurement. A total of 240 specimens were prepared. UV-ES in 3 different ratios (1%, 2%, and 5%) and a control group of each silicone type were generated (n=10). The effects of maxillofacial silicone type and ultraviolet protective ratios on hardness, tensile strength, percentage elongation, and tear strength were examined by factorial ANOVA (α=.05).

RESULTS

The Shore-A hardness in the control and UV-ES added groups was not significantly different in M511 material (P>.05), and a statistically significant decrease was observed in all ratios in TechSil S-25 and A-2000 silicones (P<.05). After adding 1%, 2%, and 5% UV protective into the silicones, the tensile strength and elongation of TechSil S-25 silicone material decreased significantly (P<.05), while these mechanical properties of M511 and A-2000 were not affected by UV-ES addition (P>.05). Tensile and tear strength values of the silicone elastomers were highest for TechSil S-25.

CONCLUSIONS

The mechanical properties of M511 and A-2000 silicone elastomers were not adversely affected by the addition of 1%, 2%, or 5% UV-ES.

Outcome measures in facial prosthesis research: A systematic review

STATEMENT OF PROBLEM

Facial prosthesis research uses a wide variety of outcome measures, which results in challenges when comparing the effectiveness of interventions among studies. Consensus is lacking regarding the most appropriate and meaningful outcome measures to use in facial prosthesis research to capture important perspectives.

PURPOSE

The purpose of the systematic review was to identify and synthesize outcome measures used in facial prosthesis research.

MATERIAL AND METHODS

Electronic searches were performed in 11 databases (including nonpeer-reviewed literature). The citations were searched, and expert societies were contacted to identify additional studies. Inclusion criteria comprised studies of participants with facial defects who required or had received prosthetic rehabilitation with an external facial prosthesis. Exclusion criteria comprised participants with ocular prostheses, case reports, case series with fewer than 5 participants, laboratory-based studies, and studies published before 1980. Study selection was performed independently by 2 reviewers. Discrepancies were resolved through discussion or by a third reviewer. Outcome measures were synthesized with a categorization approach based on the perspective, theme, and subtheme of the outcome measures. Quality assessment was performed with an appraisal tool that enabled evaluation of studies with diverse designs.

RESULTS

Database searching identified 13 058 records, and 7406 remained after duplications were removed. After initial screening, 189 potentially relevant records remained, and 186 full texts were located (98% retrieval rate). After full-text screening, 124 records were excluded. Citation searches and contact with expert societies identified 4 further records. In total, 69 articles (grouped into 65 studies) were included. Studies were categorized as per the perspective of their outcome measures, with the following findings: patient-reported (74% of studies), clinical indicators (34%), clinician-reported (8%), multiple viewpoints (6%), and independent observer-reported (3%). Patient-reported outcome measures included tools to assess satisfaction, quality of life, and psychologic health. Variability in the choice of outcome measures was evident among the studies, with many self-designed, unvalidated, condition-specific questionnaires reported. A greater number of outcome measure themes emerged over time; themes such as service delivery and health state utility have recently been evaluated.

CONCLUSIONS

Over the past 40 years, facial prosthesis research has focused on patient-reported outcome measures. Outcome measures relating to other perspectives have been used less frequently, although new themes appear to be emerging in the literature. Future research should use outcome measures with appropriate measurement properties for use with facial prosthetics.

Ultraviolet C as a method of disinfecting medical silicone used in facial prostheses: An in vitro study

STATEMENT OF PROBLEM

Hygiene and disinfection are important factors for preserving facial prostheses and supporting tissue health. However, a method that does not accelerate degradation or color change is necessary.

PURPOSE

The purpose of this in vitro study was to evaluate the effectiveness of irradiation with ultraviolet C light-emitting diode (UV-C LED) light in the disinfection and initial color stability of the silicone (A-588-1; Factor II) used in facial prostheses.

MATERIAL AND METHODS

One hundred and twenty specimens were made, contaminated by multispecies biofilm, and divided into 5 groups (n = 24) with different treatments: control, distilled water, 0.12% chlorhexidine, UV-C LED light, and dimethyl sulfoxide (DMSO) as the negative control. Cell viability was measured by the methyl tetrazolium salt method. Statistical analysis was performed by generalized linear models. Additional descriptive analysis was performed for color analysis by using 16 silicone specimens made with light and dark intrinsic coloring in 4 groups (controls and treatments n=4) submitted to UV-C LED light. The ΔE of the specimens was obtained by CIEDE200.

RESULTS

The results of cell viability demonstrated a statistically significant difference among the groups (P<.001), with a microbial reduction after UVC-LED exposure compared with the control group. Regarding the color, the groups presented an average ΔE (light 0.205 and dark 0.308) compatible with visually imperceptible changes (light < 0.7 and dark < 1.2).

CONCLUSIONS

Irradiation with UV-C LED light decreased the in vitro microbial cell viability of the medical silicone used in facial prostheses, demonstrating initial color stability.

Craniofacial implants in a failed autologous reconstruction of microtia: a case report

Plastic surgical reconstruction is considered to be the gold standard for the repair of microtia as the results are permanent and constructed from the patient's own tissue; however, the multiple surgeries required and the difficulty in attaining adequate cosmetic results often result in patients choosing a prosthesis as a long-term rehabilitation. Advances in osseointegration in the craniofacial region have improved the outcomes with auricular prosthetics by providing a reliable method of attachment of the prosthesis and increasing patient acceptance. A case presentation illustrates the results of both treatment modalities and examines the outcomes on the same patient.

Visual and instrumental color evaluation of computerized color matching system for color reproduction of maxillofacial prostheses

STATEMENT OF PROBLEM

A commercially available computerized color matching system (e-Skin) has been introduced for maxillofacial prostheses. However, studies that have tested its ability to produce an acceptable color match for skin color are lacking.

PURPOSE

The purpose of this clinical study was to determine the color match acceptability of light and dark skin silicone replicas fabricated with the use of the computerized color matching system.

MATERIAL AND METHODS

Fifteen participants with light skin and 15 participants with dark skin were recruited through personal invitation. These 30 participants (aged around 20 years) voluntarily consented to forearm skin color measurements with a spectrophotometer and a spectrocolorimeter integrated in a computerized color matching system. Silicone skin replicas for each participant were produced from the color formulations provided by the online calculator tool of the system according to the manufacturers' recommendations. The color difference between initial skin color measurements with the spectrophotometer and skin replica color measurements with the spectrophotometer for all participants was calculated by using both the CIELab (ΔE∗ab) and CIEDE2000 (ΔE00) color difference formulas. To compare the instrumental and visual evaluation of color match, 3 observers (a maxillofacial prosthodontist, a prosthodontist, and a postgraduate student) visually evaluated and rated the color match of each silicone replica on a 5-point scale. Statistical analyses were performed by using the Student t, Mann Whitney U, and chi-square tests (α=.05).

RESULTS

No significant differences were detected between the light and dark skin groups in terms of the ΔE∗ab and ΔE00 values obtained between the first skin color measurements and their silicone replica color measurements (P=.573, P=.338, respectively). However, a significant difference was found between light and dark skin groups for the ΔL and Δa values obtained from the same measurements (P=.031, P=.017, respectively). L∗, a∗, and b∗ values of light skin were significantly higher than those of their silicone replications (P=.008, P=.033, P=.046, respectively). Color match ratings of observers did not significantly differ when comparing the ratings of light skin replicas to ratings of dark skin replicas.

CONCLUSIONS

The e-Skin system provided skin replicas that matched the skin color within clinically acceptable thresholds and with ratings of at least "good" by experienced dental clinicians.

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.

Automated Noncontact Facial Topography Mapping, 3-Dimensional Printing, and Silicone Casting of Orbital Prosthesis

PURPOSE

A proof-of-concept workflow study for the fabrication of custom orbital exenteration prostheses via automated noncontact scanning, 3D printing, and silicone casting.

DESIGN

Noncomparative, interventional case series.

METHODS

Setting: Single-center institutional study. StudyPopulation: Three patients who have discontinued wearing of the ocularist-made exenteration prosthesis due to altered fit, discoloration, or material degradation. InterventionProcedure: A digital representation of the exenteration socket and contralateral periocular region was captured through noncontact facial topography mapping. Digital construction of the anterior prosthesis surface was based on the mirrored image of the contralateral side, and the posterior surface contour was based on orbital cavity geometry. The anterior and posterior surface details were digitally merged. A 2-piece mold was designed and produced in a 3D printer. Colorimetry was used to create a custom blend of pigments for incorporation into the Shore 40 silicone elastomer to generate a prosthesis that approximates the patient's skin tone. MainOutcomeMeasures: Prosthesis symmetry, skin tone match, comfort of wear, and appearance.

RESULTS

The first copy of every 3D-printed orbital prosthesis using this fabrication workflow produced good symmetry, color match, and prosthesis fit. In one case, the recontoured second copy with improved prosthesis edge-to-skin interface was made without the patient present.

CONCLUSION

A noncontact 3D scanning, computer-aided design, 3D printing, and silicone casting for fabrication of orbital prosthesis was developed and validated. This production workflow has the potential to provide an efficient, standardized, reproducible exenteration prosthesis and to overcome the principal barriers to an affordable custom prosthesis worldwide: access and cost.

Prosthetic Facial Reconstruction in a Blast Injury Case

The management of blast and burn injuries to the facial soft tissue and craniomaxillofacial skeleton has been a challenge since the inception of reconstructive plastic surgery. These injuries continue to present complex reconstructive challenges today. While there have been advancements in free tissue transfer and vascularized composite allotransplantation, prosthetics have been used successfully since antiquity until the present day. Prosthetics may achieve acceptable coverage without complex surgery or as an adjunct to reconstructive surgery. Here, we report a case of devastating blast injury to the face that has been managed successfully with orbital prosthetics anchored with osseointegrated implants.

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.

Advancements in Soft-Tissue Prosthetics Part A: The Art of Imitating Life

Physical disfigurement due to congenital defects, trauma, or cancer causes considerable distress and physical impairment for millions of people worldwide; impacting their economic, psychological and social wellbeing. Since 3000 B.C., prosthetic devices have been used to address these issues by restoring both aesthetics and utility to those with disfigurement. Internationally, academic and industry researchers are constantly developing new materials and manufacturing techniques to provide higher quality and lower cost prostheses to those people who need them. New advanced technologies including 3D imaging, modeling, and printing are revolutionizing the way prostheses are now made. These new approaches are disrupting the traditional and manual art form of prosthetic production which are laborious and costly and are being replaced by more precise and quantitative processes which enable the rapid, low cost production of patient-specific prostheses. In this two part review, we provide a comprehensive report of past, present and emerging soft-tissue prosthetic materials and manufacturing techniques. In this review, part A, we examine, historically, the ideal properts of a polymeric material when applied in soft-tissue prosthetics. We also detail new research approaches to target specific tissues which commonly require aesthetic restoration (e.g. ear, nose and eyes) and discuss both traditional and advanced fabrication methods, from hand-crafted impression based approaches to advanced manufactured prosthetics. We discuss the chemistry and related details of most significant synthetic polymers used in soft-tissue prosthetics in Part B. As advanced manufacturing transitions from research into practice, the five millennia history of prosthetics enters a new age of economic, personalized, advanced soft tissue prosthetics and with this comes significantly improved quality of life for the people affected by tissue loss.

Implant-Retained Nasal Prosthesis with Bar and Clip for a Patient with Total Rhinectomy: A Clinical Report

The present clinical report describes the fabrication of an implant -retained prosthesis with bar and clip retention for a patient with total rhinectomy due to basal cell carcinoma (BCC). The nasal prosthesis was retained on the face by a reverse Y-shaped bar with horizontal and vertical extensions, resulting in favorable retention and function.

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.

Maxillofacial prosthetic rehabilitation: A survey on the quality of life

STATEMENT OF PROBLEM

Maxillofacial prostheses, especially those supported by endosseous implants, are regarded as a viable, secure treatment for the reconstruction of facial defects to restore quality of life. The long-term quality of life of patients treated with facial prostheses with different retentive systems is unclear.

PURPOSE

The purpose of this clinical study was to assess the long-term quality of life of patients treated with facial prostheses with different retentive systems over a 14-year period at a Dutch oral and maxillofacial surgery unit.

MATERIAL AND METHODS

A total of 66 patients with facial prostheses were inventoried and categorized based on anatomic location and type of retention. A 62-item questionnaire was designed to survey the daily prosthetic use, care, quality, durability, longevity, and reliability of retention. Furthermore, issues relating to general satisfaction, self-image, and socialization frequency were addressed.

RESULTS

Completed validated questionnaires were returned by 52 patients. Of the prosthetic replacements, 23% (n=12) were orbital, 33% (n=17) nasal, and 44% (n=23) auricular prostheses. The survey showed that a prosthetic reconstruction led to high satisfaction scores with regard to wearing comfort, anatomic fit, color, and anatomic form. A significant difference was shown for implant-retained facial prostheses, which provided enhanced retention and increased ease of placement and removal (Fisher exact test P=.01 and P=.04). Patients with nasal prostheses were less satisfied with the junction of their prostheses to the surrounding soft tissue and more aware of others noticing their prosthetic rehabilitation. Patients with auricular defects were less embarrassed (P=.01) by their prostheses. Although auricular prostheses were less frequently cleaned (P=.01), no significant difference was found in minor soft tissue complications between different anatomic locations and the various retentive systems.

CONCLUSIONS

Implant-retained prostheses have advantages over adhesive-retained prostheses in terms of ease of handling. However, improvements in prosthetic material properties, including color stability and durability, are needed to increase the longevity of facial prostheses.

Mechanical and Morphological Effect of Plant Based Antimicrobial Solutions on Maxillofacial Silicone Elastomer

The objective of this study was to determine the effect of plant based antimicrobial solutions specifically tea tree and Manuka oil on facial silicone elastomers. The purpose of this in vitro study was to evaluate the effect of disinfection with plant extract solution on mechanical properties and morphology on the silicone elastomer. Test specimens were subjected to disinfection using tea tree oil, Manuka oil and the staphylococcus epidermidis bacteria. Furthermore, a procedure duration was used in the disinfection process to simulate up to one year of usage. Over 500 test specimens were fabricated for all tests performed namely hardness, elongation, tensile, tear strength tests, visual inspection and lastly surface characterization using SEM. A repeated measures ANOVA revealed that hardness and elongation at break varied significantly over the time period, whereas this was not observed in the tear and tensile strength parameters of the test samples.

Maxillofacial prostheses challenges in resource constrained regions

BACKGROUND

This study reviewed the current state of maxillofacial rehabilitation in resource-limited nations.

METHOD

A rigorous literature review was undertaken using several technical and clinical databases using a variety of key words pertinent to maxillofacial prosthetic rehabilitation and resource-limited areas. In addition, interviews were conducted with researchers, clinicians and prosthetists that had direct experience of volunteering or working in resource-limited countries.

RESULTS

Results from the review and interviews suggest rehabilitating patients in resource-limited countries remains challenging and efforts to improve the situation requires a multifactorial approach.

CONCLUSIONS

In conclusion, public health awareness programmes to reduce the causation of injuries and bespoke maxillofacial prosthetics training programmes to suit these countries, as opposed to attempting to replicate Western training programmes. It is also possible that usage of locally sourced and cheaper materials and the use of low-cost technologies could greatly improve maxillofacial rehabilitation efforts in these localities. Implications for Rehabilitation More information and support needs to be provided to maxillofacial defect/injuries patients and to their families or guardians in a culturally sensitive manner by governments. The health needs, economic and psychological needs of the patients need to be taken into account during the rehabilitation process by clinicians and healthcare organizations. The possibility of developing training programs to suit these resource limited countries and not necessarily follow conventional fabrication methods must be looked into further by educational entities.

Osseointegrated Implants and Prosthetic Reconstruction Following Skull Base Surgery

Rehabilitation following ablative skull base surgery remains a challenging task, given the complexity of the anatomical region, despite the recent advances in reconstructive surgery. Remnant defects following resection of skull base tumors are often not amenable to primary closure. As such, numerous techniques have been described for reconstruction, including local rotational muscle flaps, pedicled flaps with skin paddle, or even free tissue transfer. However, not all patients are appropriate surgical candidates and therefore may instead benefit from nonsurgical options for functional and aesthetic restoration. Osseointegrated implants and biocompatible prostheses provide a viable alternative for such a patient population. The purpose of this review serves to highlight current options for prosthetic rehabilitation of skull base defects and describe their indications, advantages, and disadvantages.

The prosthetic rehabilitation of a patient with a lateral postsurgical defect using a 2-piece magnet-retained facial prosthesis: A clinical report

Nonsurgical prosthetic interventions are often proposed after repeated grafts have failed to restore irradiated facial defects. This report describes a facial prosthetic reconstruction following ablative surgery for a sizable facial tumor by using a novel custom-made magnet-bearing substructure, which connected with an exposed part of the mandibular reconstruction plate. The defect involved the entire left lower part of the face and angle of the mentum. This reconstructive technique, together with an added surface texture with hair-like silicone strands, effectively addressed the cosmetic needs of the patient. Magnetic anchorage to an exposed reconstruction plate could be considered an option for retaining facial prostheses. The biomechanical aspects of loading and retention should be addressed before considering this prosthetic option.

Initial investigation of the corrosion stability of craniofacial implants

STATEMENT OF PROBLEM

Although craniofacial implants have been used for retention of facial prostheses, failures are common. Titanium undergoes corrosion in the oral cavity, but the corrosion of craniofacial implants requires evaluation.

PURPOSE

The purpose of this in vitro study was to investigate the corrosion stability of commercially pure titanium (CP Ti) exposed to simulated human perspiration at 2 different pH levels (5.5 and 8).

MATERIAL AND METHODS

Fifteen titanium disks were divided into 3 groups (n=5 per group). The control group was subjected to simulated body fluid (SBF) (control). Disks from the 2 experimental groups were immersed in simulated alkaline perspiration (SA_KP) and simulated acidic perspiration (SA_CP). Electrochemical tests, including open circuit potential (3600 seconds), electrochemical impedance spectroscopy, and potentiodynamic tests were performed according to the standardized method of 3-cell electrodes. Data were analyzed by 1-way ANOVA and the Tukey honestly significant difference tests (α=.05).

RESULTS

Simulated human perspiration reduced the corrosion stability of CP Ti (P<.05). The SBF group presented the lowest capacitance values (P<.05). SA_KP and SA_CP groups showed increased values of capacitance and showed no statistically significant differences (P>.05) from each other. The increase in capacitance suggests that the acceleration of the ionic exchanges between the CP Ti and the electrolyte leads to a lower corrosion resistance. SA_KP reduced the oxide layer resistance of CP Ti (P<.05), and an increased corrosion rate was noted in both simulated human perspiration groups.

CONCLUSIONS

Craniofacial implants can corrode when in contact with simulated human perspiration, whereas alkaline perspiration shows a more deleterious effect. Perspiration induces a more corrosive effect than simulated body fluid.

A decomposable silica-based antibacterial coating for percutaneous titanium implant

Although percutaneous titanium implants have become one of the best choices as retainers in the facial defects, peri-implantitis still occurs at a significant rate. This unwanted complication occurs due to adhesion of bacteria and subsequent biofilm formation. To solve this problem, we have developed a novel antibiotic nanodelivery system based on self-decomposable silica nanoparticles. In this study, silica-gentamycin (SG) nanoparticles were successfully fabricated using an innovative one-pot solution. The nanoparticles were incorporated within a gelatin matrix and cross-linked on microarc-oxidized titanium. To characterize the SG nanoparticles, their particle size, zeta potential, surface morphology, in vitro drug release, and decomposition process were sequentially evaluated. The antibacterial properties against the gram-positive Staphylococcus aureus, including bacterial viability, antibacterial rate, and bacteria morphology, were analyzed using SG-loaded titanium specimens. Any possible influence of released gentamycin on the viability of human fibroblasts, which are the main component of soft tissues, was investigated. SG nanoparticles from the antibacterial titanium coating continuously released gentamycin and inhibited S. aureus growth. In vitro investigation showed that the obtained nanodelivery system has good biocompatibility. Therefore, this design can be further investigated as a method to prevent infection around percutaneous implants.

Stability of the prosthetic screws of three types of craniofacial prostheses retention systems

Objectives

This study aimed to evaluate the stability of prosthetic screws from three types of craniofacial prostheses retention systems (bar-clip, ball/O-ring, and magnet) when submitted to mechanical cycling.

Materials and Methods

Twelve models of acrylic resin were used with implants placed 20 mm from each other and separated into three groups: (1) bar-clip (Sistema INP, São Paulo, Brazil), (2) ball/O-ring (Sistema INP), and (3) magnet (Metalmag, São Paulo, Brazil), with four samples in each group. Each sample underwent a mechanical cycling removal and insertion test (f=0.5 Hz) to determine the torque and the detorque values of the retention screws. A servo-hydraulic MTS machine (810-Flextest 40; MTS Systems, Eden Prairie, MN, USA) was used to perform the cycling with 2.5 mm and a displacement of 10 mm/s. The screws of the retention systems received an initial torque of 30 Ncm and the torque values required for loosening the screw values were obtained in three cycles (1,080, 2,160, and 3,240). The screws were retorqued to 30 Ncm before each new cycle.

Results

The sample was composed of 24 screws grouped as follows: bar-clip (n=8), ball/O-ring (n=8), and magnet (n=8). There were significant differences between the groups, with greater detorque values observed in the ball/O-ring group when compared to the bar-clip and magnet groups for the first cycle. However, the detorque value was greater in the bar-clip group for the second cycle.

Conclusion

The results of this study indicate that all prosthetic screws will loosen slightly after an initial tightening torque, also the bar-clip retention system demonstrated greater loosening of the screws when compared with ball/O-ring and magnet retention systems.

Ocular Reconstruction Using Bone-Anchored Implants in Irradiated Facial Deformities After Tumor Extirpation

BACKGROUND

Surgical resection of ocular malignancies can result in complex craniofacial defects that can be difficult to reconstruct with conventional reconstruction techniques. Craniofacial prosthesis supported by bone-anchored implants has evolved as a reliable alternative in such scenarios.

METHODS

The authors describe a patient who underwent extensive facial resection secondary to squamous cell carcinoma resulting in significant facial deformities. A bone-anchored osseointegrated implant was used to perform facial reconstruction.

RESULTS

The patient had successful reconstruction of her orbit with bone-anchored implant. However, her implant needed to be removed 10 months postoperatively secondary to infection. A second attempt at implant placement has been deferred due to osteonecrosis secondary to adjuvant radiotherapy.

CONCLUSION

Bone-anchored implants can provide an elegant alternative in the reconstruction of complex facial defects and provide direct access to surveillance for possible tumor recurrence. However, these bone-supported prosthetics should be used with caution in patients undergoing irradiation.

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.

Rehabilitation of a complex midfacial defect by means of a zygoma-implant-supported prosthesis and nasal epithesis: a novel technique

Purpose

Several authors have described zygoma implants as a reliable surgical option to rehabilitate severe maxillary defects in case of extreme atrophy or oncological resections. The aim of this study is to report a new technical approach to the rehabilitation of a complex oronasal defect by means of a zygoma-implant-supported full-arch dental prosthesis combined with a nasal epithesis.

Patients and methods

The patient presented with a subtotal bilateral maxillectomy and total rhinectomy defect because of a squamous cell carcinoma of the nose. No reconstructive surgery was performed because of the high risk of recurrence; moreover, the patient refused any secondary procedure. After surgery, the patient presented a wide palatal defect associated to the absence of the nasal pyramid. Zygoma-retained prostheses are well documented, and they offer good anchorage in rehabilitating wide defects after oncological surgery and a good chance for patients to improve their quality of life. We hereby describe two prosthetic devices rehabilitating two iatrogenic defects by means of a single intraoral implant-supported bar extending throughout the oronasal communication, thus offering nasal epithesis anchorage.

Results

At 1-year follow-up after functional prosthetic loading, no implant failure has been reported. Clinical and radiological follow-up showed no sign of nasal infection or peri-implantitis. The patient reported a sensitive improvement of his quality of life.

Conclusions

Simultaneous oral and nasal rehabilitation of complex oronasal defects with zygoma-implant-supported dental prosthesis and nasal epithesis represents a reliable surgical technique. According to this clinical report, the above-mentioned technique seems to be a valuable treatment option as it is safe, reliable and easy to handle for both surgeon and patient.

Bone and Skin-Supported Stereolithographic Surgical Guides for Cranio-Facial Implant Placement

PURPOSE

Osseointegrated skin-penetrating implants enhance the retention and stability of the craniofacial prostheses and provide the long-term comfort. However, to determine the implant locations is a great challenge facing the surgeon. Implants may either be located in conventional manner or by STL generated surgical guides.

MATERIALS AND METHODS

Present study reports the CT based 3D virtual modeling, preoperative virtual planning and the implant placement by using a STL surgical guide, in an anotia case.

RESULTS

Employed materials and the methods facilitated the implant surgery while improving the operational security.

CONCLUSIONS

CT based 3D virtual modeling of the surgical site, determining the implant locations virtually and the STL guided placement of the craniofacial implants, were found useful applications in order to facilitating the surgical intervention and providing prevention from complications.

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.

Patients' satisfaction with facial prostheses

We assessed the "impact on wellbeing" and "satisfaction" of patients who had a facial prosthesis (of the ear, nose, or orbit) fitted in The Netherlands Cancer Institute. Patients had either an adhesive-retained or an implant-retained facial prosthesis between 1951 and 2011. We did a cross-sectional survey of 104 patients, then gave a questionnaire to the final study group of 71 (68%), a year or more later. All were satisfied with their prostheses (visual analogue scale (VAS): mean (SD) 8.1(1.5). The implant-retained group were the most satisfied (p=0.022), and the adhesive-retained group felt more self-conscious (p=0.013). Three-quarters of all patients said that the prosthesis was not painful and there were no problems with the way it functioned. A well-designed facial prosthesis has obvious benefits, but there were no appreciable differences between the two groups. Each patient must make a careful decision about which type of prosthesis to choose, taking into account the quality of their remaining tissue, the site of the defect, and their general health.

Innovative Approach for Interim Facial Prosthesis Using Digital Technology

Despite the important role of facial prosthetic treatment in the rehabilitation of head and neck cancer patients, delay in its implementation can be unavoidable, preventing patients from receiving a prompt facial prosthesis and resuming a normal social life. Here, we introduce an innovative method for the fabrication of an interim facial prosthesis. Using a 3D modeling system, we simplified the fabrication method and used a titanium reconstruction plate for facial prosthesis retention. The patient received the facial prosthesis immediately after surgery and resumed a normal social life earlier than is typically observed with conventional facial prosthetic treatment.

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.

Efficacy of cleansing agents in killing microorganisms in mixed species biofilms present on silicone facial prostheses--an in vitro study

OBJECTIVES

The purpose of this study was to assess the efficacy of different cleansing agents in killing mixed species biofilms on silicone facial prostheses.

MATERIALS AND METHODS

Two bacterial and three yeast strains, isolated from silicone facial prostheses, were selected for the mixed species biofilms. A variety of agents used to clean facial prostheses were employed, viz., antibacterial soap, essential-oil-containing mouth rinse, ethanol 27 %, chlorhexidine mouth rinse, and buttermilk. Colony forming units (CFUs) and live/dead staining were analyzed to assess the efficacy of these cleansing agents against 24-h and 2-week biofilms and regrown biofilms on silicone samples.

RESULTS

Chlorhexidine was the most effective cleansing agent. Chlorhexidine killed 8 log unit CFUs (>99.99 % killing) in a 24-h biofilm and 5 log unit CFUs (>99.99 % killing) in 2-week biofilms. Also, after regrowth and repeated treatment of the biofilm, chlorhexidine was the most effective cleansing agent showing no detectable CFUs. The essential-oil-containing mouth rinse (containing 26.9 % ethanol) showed a similar efficacy as ethanol (27 %) alone. Antibacterial soap and buttermilk were the least effective agents tested.

CONCLUSIONS

Chlorhexidine showed the highest reduction in CFUs in 24-h, 2-week, and regrown mixed species biofilm of microorganisms isolated from silicone facial prostheses.

CLINICAL RELEVANCE

Chlorhexidine mouth rinse (easy obtainable and relatively cheap) is very effective in killing bacteria and yeast present in biofilms on silicone facial prostheses. When applied on a regular basis, cleansing a facial prosthesis with chlorhexidine will presumably increase its lifetime and reduce skin irritations.

Effect of light aging on silicone-resin bond strength in maxillofacial prostheses

PURPOSE

The aim of this study was to investigate the effect of accelerated light aging on bond strength of a silicone elastomer to three types of denture resin.

MATERIALS AND METHODS

A total of 60 single lap joint specimens were fabricated with auto-, heat-, and photopolymerized (n = 20) resins. An addition-type silicone elastomer (Episil-E) was bonded to resins treated with the same primer (A330-G). Thirty specimens served as controls and were tested after 24 hours, and the remaining were aged under accelerated exposure to daylight for 546 hours (irradiance 765 W/m(2) ). Lap shear joint tests were performed to evaluate bond strength at 50 mm/min crosshead speed. Two-way ANOVA and Tukey's test were carried out to detect statistical significance (p < 0.05).

RESULTS

ANOVA showed that the main effect of light aging was the most important factor determining the shear bond strength. The mean bond strength values ranged from 0.096 to 0.136 MPa. The highest values were recorded for auto- (0.131 MPa) and photopolymerized (0.136 MPa) resins after aging.

CONCLUSIONS

Accelerated light aging for 546 hours affects the bond strength of an addition-type silicone elastomer to three different denture resins. The bond strength significantly increased after aging for photo- and autopolymerized resins. All the bonds failed adhesively.

Prosthetic reconstruction of a patient with an acquired nasal defect using extraoral implants and a CAD/CAM copy-milled bar

Traditionally, patients with maxillofacial defects have been challenging to treat. A multitude of challenges associated with maxillofacial prosthetic treatment are not typically seen with patients who need conventional prosthodontic treatment. These types of patients generally require replacement of significant amounts of hard and soft tissues than do conventional prosthodontic patients. Most maxillofacial patients also warrant more emotional support than do conventional prosthodontic patients. Successful maxillofacial prosthetics still need to embrace the traditional goals of prosthodontic treatment: stability, support, retention, and esthetics. It is unlikely that a maxillofacial prosthesis will exactly duplicate the anatomy and function of missing or damaged structures. Although craniofacial implants (CFI's) have lower cumulative survival rates (CSR's) than intraoral endosseous implants, osseointegrated CFI's have proven to be significant adjuncts to improving retention of maxillofacial prostheses. However, CSR's of CFI's have been reported to be lower than CSR's for intraoral endosseous implants. Lately, computer-assisted design and computer-assisted machining (CAD/CAM) has been used in dentistry to facilitate fabrication of implant-supported frameworks. CAD/CAM protocols have numerous advantages over conventional casting techniques, including improved accuracy and biocompatibility, and decreased costs. The purpose of this paper is to review the literature on cumulative survival rates (CSR's) reported for CFI's and to illustrate the treatment of a maxillofacial patient using CFI's and a CAD/CAM copy-milled framework for retention and support of a nasal prosthesis.

Quality of life of patients with implant-retained maxillofacial prostheses: a prospective and retrospective study

STATEMENT OF PROBLEM

Clinical studies on implant-retained maxillofacial prostheses have focused on biological outcomes. An assessment of the effect of prostheses on patients' quality of life (QOL) by using specific questionnaires developed for this patient population provides important information on treatment outcomes from the patients' perspectives.

PURPOSE

The purpose of this study was to report patient-based outcomes of implant-retained maxillofacial prostheses and to evaluate the effect of implant-retained maxillofacial prostheses on QOL of participants in a prospective study.

MATERIAL AND METHODS

Eighty-two participants were treated with implant-retained maxillofacial prostheses. Participants were divided into 2 groups: a retrospective group (participants treated and under care) and a prospective group (participants willing to be treated). The posttreatment patient satisfaction scores for each question were statistically analyzed by 2-way ANOVA with variables of defect type and retention type. The Student-Newman-Keuls test was used to determine any significant differences among the groups. In the prospective group, mean scores before and after prosthetic treatment were compared with the paired t test (α=.05).

RESULTS

The details of 54 retrospective and 28 prospective participants were reviewed. The posttreatment results of 82 patients showed that patient satisfaction with implant-retained maxillofacial prostheses was significantly different for cleaning the prostheses and recommending treatment to other people, depending on the defect and retention type. In the prospective group, participants reported significant increases in satisfaction for all questions.

CONCLUSIONS

Implant-retained prostheses were considered highly satisfactory, indicating good QOL for patients with maxillofacial defects. A comparison of pretreatment and posttreatment assessments revealed that implant-retained maxillofacial prostheses increased patient QOL.

Influence of pigments and pigmenting methods on color stability of different silicone maxillofacial elastomers after 1-year dark storage

PURPOSE

The purpose of this study was to measure spectrophotometrically the color changes of pigmented maxillofacial silicone elastomers with different pigments and pigmenting methods after storing 1 year in the dark environment.

METHODS

Three maxillofacial silicones, Cosmesil M511 (CosM511), Cosmesil M522 (CosM522), and Multisil-Epithetic (Mult-Epit), were selected for this study. A total of 240 specimens were fabricated; 80 of each of the 3 elastomers (n = 5) (18 mm in diameter and 2 mm in thickness) were prepared in 6 colorant categories (5 colorant and 1 with no colorant). Specimens were stored in a black box representing a condition of total darkness and placed in a dark environment at ambient room temperature (22°C ± 10°C) and humidity (50% ± 10%) for 1 year. A color spectrophotometer was used to measure the ΔE* values of the test specimens to determine the color changes.

RESULTS

The lowest color changes were observed in CosM511 in white color (ΔE* = 1.31) and in Mult-Epit in white color (ΔE* = 1.82) in extrinsic coloration group. The highest color changes were observed in yellow color in CosM511 (ΔE*= 21.61) and CosM522 (ΔE*= 23.78) in silicone pigmented intrinsic coloration method. In coloration methods, intrinsic silicone pigmented groups in all colors except brown in Mult-Epit had the highest ΔE* values.

CONCLUSIONS

Significant color changes were observed in both pigmented and unpigmented specimens, which were stored in dark environment and not exposed to sunlight.

Esthetic, functional, and prosthetic outcomes with implant-retained finger prostheses

BACKGROUND

Traumatic amputation of fingers results in a serious impairment of hand function and affects the psychological status of the patients. The implant-retained finger prostheses are an alternative treatment. The aim of this case report is to represent the use of osseointegrated implants for retention of finger prostheses in a patient with amputated thumb and index finger.

CASE DESCRIPTION AND METHODS

Dental implants were placed in the residual bone of the fingers using two-stage surgery. Custom-made attachments were used to provide retention between implants and silicone prostheses. Prosthetic fingernails were made of composite resin material.

FINDINGS AND OUTCOMES

After 6 months, implants were clinically successful, and the patient was satisfied with the appearance and the function of the prostheses. The complications of broken prosthetic nail and mild discoloration were observed.

CONCLUSION

Reconstruction of amputated fingers with implant-retained prosthesis is a worthwhile treatment providing esthetic, functional, and psychological benefits, although some complications might be experienced. Clinical relevance Implant-retained finger prostheses are an acceptable treatment modality for patients with amputated fingers. Evaluating implant prognosis, functional results and prosthetic results of the patients are necessary to address the benefits and complications of the treatment.