Irradiated patients and survival rate of dental implants: A systematic review and meta-analysis

Multicenter 14-year follow-up of fibula vascular grafts of mandibles and maxillae restored with short and extra-short implants

PURPOSE

This multi-center retrospective study evaluated the survival and success of extra-short and short locking-taper dental implants placed in both maxillary and mandibular fibula grafts.

METHODS

A total of 37 patients were treated across five study sites and received 146 implants in fibula grafted sites. Out of those patients, 23 received prostheses, and they received 25 prostheses in total. Kaplan-Meier survival analysis was used to assess the survival and success rates of both implants and prostheses. Multivariate Cox regression and manifold learning were used to correlate study covariates to implant survival outcomes. Marginal bone levels surrounding implants supporting full arch prostheses were measured and correlated with the lengths of distal extensions.

RESULTS

The overall thirteen-year implant survival rate was 86.9 % (95 % confidence interval: 75.5-93.2 %), while the implant success rate was 80.2 % (95 % confidence interval: 66.8-88.7 %.) The prosthesis survival rate at 13 years after prosthesis insertion was 90.0 % (95 % confidence interval: 65.6-97.4 %); while the prosthetic success rate was 78.9 % (95 % confidence interval: 56.2-90.7 %.) Hypertension, implant placement in the mandible, tooth loss from tumor, patient age, and lateral augmentation were correlated with reduced implant survival; while maxillary implant placement, osteoporosis and antiresorptive drug use, chemotherapy before implant surgery, and tooth loss from trauma were correlated with improved survival. Marginal bone levels around implant immediately adjacent to distal extensions were positively correlated with the lengths of distal extensions (R2 = 0.74).

CONCLUSION

Extra short and short locking-taper dental implants presented high survival and success rates when used to restore the dentition of patients receiving fibula grafts for maxillary or mandibular reconstruction.

Osteoradionecrosis Incidence and Dental Implant Survival in Irradiated Head and Neck Cancer Patients: A Systematic Review and Meta-Analysis

BACKGROUND AND AIM

The use of implants in irradiated patients has been critically questioned due to the presence of Osteoradionecrosis and other side effects of radiation therapy. Hence, our objective is to examine the likelihood of dental implant survival and the incidence of osteoradionecrosis in patients with head and neck cancer who have undergone radiation therapy. This analysis will aid in making informed therapeutic decisions on oral rehabilitation for individuals at high risk, ensuring maximal benefit.

METHOD

PubMed, Scopus, and Web of Science were queried until April 2024. The digital data were extracted using the Web plot digitizer. We utilized the most recent iteration of STATA (version 18) to perform a meta-analysis of the data. The studies were evaluated for quality using the New Castle-Ottawa Scale. Egger's test was used to evaluate the presence of publication bias caused by modest research effects.

RESULT

The study analyzed data from 21 research papers on 753 head and neck cancer patients. The majority were male, with a mean age of 60.25 years. 46% underwent radiotherapy, with 2261 dental implants inserted. The mandible was the most used implant site, accounting for 62.4%. The mean time between implant placement and radiotherapy was 5.3 weeks, with a median waiting period of 30.7 months for secondary surgery. After an average follow-up of 42.25 months, 58% of implants failed in the irradiated control group, while 6% failed in the non-irradiated control subgroup. Osteoradionecrosis was seen in 26 patients, resulting in an incident rate of 1.81%. As a result of this problem, an average of 2.5 implants per patient were not successfully retained. Radiotherapy was found to be a significant risk factor for implant survival.

CONCLUSION

Our research indicates that the survival rate of implants in patients who have undergone radiation therapy is lower compared to those who have not received radiation therapy. Additionally, although rare, osteoradionecrosis is a significant complication that every oral and maxillofacial surgeon should be ready to address. Enhancing the quality of care, mitigating hazards, and reducing treatment duration may hinge upon implementing a systematic approach to patient selection and therapy.

Long-Term Outcomes of Dental Implants Placed in Fibula-free Flaps Used for Reconstruction of Maxillo-Mandibular Defects

The use of dental implants and prostheses in the oral rehabilitation process after maxillofacial ablation procedures is now regarded as standard practice. Numerous donor sites for free vascularized bone transfer in head and neck reconstruction have been well-documented in the literature including the ribs, ilium, fibula, scapula, and radius. Among these, the fibula is the most commonly used and studied for placing endosseous implants and for rehabilitation purposes. There are benefits and drawbacks to the fibula flap. This paper aims to provide a review of the current research on the long-term success rates of implants in fibula free flaps.

Osseointegrated dental implants that will undergo radiotherapy. Does risk of osteoradionecrosis exist? A scoping review

OBJECTIVE

Given the absence of a standardized action protocol for treating patients with dental implants (DIs) who are subjected to radiotherapy (RT), we have conducted an extensive review and analysis of published literature on this subject. Our objective is to gain a comprehensive understanding of the impact of RT on the bone surrounding osseointegrated implants during and after treatment.

STUDY DESIGN

We conducted a literature review using PubMed (MEDLINE) to identify studies describing the effects of RT on preexisting osseointegrated and/or loaded DIs. Articles published between January 1963 and December 2023 were considered for inclusion.

RESULTS

A total of 1,126 articles were retrieved, 64 full articles were reviewed, and only 13 articles were included in this review upon meeting the criteria. A total of 667 patients and 2,409 implants were included. Osteoradionecrosis (ORN) was observed in approximately 19 implants following antineoplastic treatment.

CONCLUSIONS

The interaction between DIs and RT is a complex and multifaceted issue that requires further research and clinical guidance. Although certain studies indicate a possible connection between DIs, radiation, and ORN risk, the precise relationship remains unclear. Factors such as radiation dosage, implant characteristics, material, and timing of placement significantly influence this association.

Site-specific radiation dosage and implant survival in oral cancer patients: A cohort study

OBJECTIVES

We assessed the radiation dosages (Dmean) on implant regions to identify the threshold for implant loss in patients with an intraoral malignancy treated with dental implants to support a mandibular denture during ablative surgery before volumetric-modulated arc therapy (VMAT).

MATERIALS AND METHODS

Data was collected prospectively from 28 patients treated surgically for an intraoral malignancy, followed by postoperative radiotherapy (VMAT) and analyzed retrospectively. Patients received 2 implants in the native mandible during ablative surgery. Implant-specific Dmean values were retrieved from the patients' files. Radiographic bone loss was measured 1 year after implant placement and during the last follow-up appointment. Implant survival was analyzed with the Kaplan-Meier method. Univariate logistic regression and Cox-regression analyses were performed to investigate the effect of increasing implant-specific radiation dosages on implant loss.

RESULTS

Five out of 56 placed implants were lost during follow-up (median 36.0 months, IQR 39.0). Radiographically, peri-implant bone loss occurred in implants with a Dmean > 40 Gy. Implant loss occurred only in implants with a Dmean > 50 Gy.

CONCLUSION

An implant-specific Dmean higher than 50 Gy is related to more peri-implant bone loss and, eventually, implant loss.

Progress of Ossification after Mandibular Reconstruction by Free Fibula Flap Depending on Different Timing of Radiotherapy: A Retrospective 3D Analysis by CT Scans

Background: The aim of this study was to evaluate the difference between pre- and post-operative radiotherapy on the progress of ossification after free fibula flap reconstruction of the mandible using three-dimensional (3D) analysis. Methods: A total of 38 free fibula reconstructions of the mandible were evaluated retrospectively for ossification between bone segments by measuring Hounsfield Units (HU) in at least two postoperative computer tomography scans (average of 2.4 scans per patient; around the 5th, 12th, 16th, and 19th month postoperative). Three subgroups were created according to the time of irradiation: preoperative radiotherapy (preORT) (n = 11), postoperative radiotherapy (postORT) (n = 16), and patients without any radiation therapy (n = 11) as the control group (noRT). HU in eight regions of interest (ROI) and overlapping surfaces between segments per contact point, as well as influencing factors, were analyzed. Results: The fastest progress in gain of HU ossification with a difference of 0.30 HU/day was observed in noRT compared to preORT (p = 0.002). postORT was -0.24 HU/day slower than preORT (p = 0.005). Original and grafted bone showed a significantly slower HU uptake than between two graft segments with -84.18 HU/day (p < 0.001). Moreover, a larger initial overlapping surface between the segments in cm2 resulted in a higher rise of HU/day (p < 0.001). Conclusions: 3D analysis of post-reconstructive CT scans shows prolonged ossification of mandible reconstructions by free fibula after head and neck radiation. The effect is distinct in cases with post-operative adjuvant radiotherapy. The effects of radiotherapy on ossification may be minimized by a larger initial contact surface and improved operational techniques. Moreover, HU longitudinal measurements and 3D analysis offer new perspectives for clinical evaluation of successful bony healing.

Optimal Treatment Order With Fibula-Free Flap Reconstruction, Oncologic Treatment, and Dental Implants: A Systematic Review and Meta-Analysis

Head and neck cancer (HNC) patients benefit from craniofacial reconstruction, but no clear guidance exists for rehabilitation timing. This meta-analysis aims to clarify the impact of oncologic treatment order on implant survival. An algorithm to guide placement sequence is also proposed in this paper. PubMed, Embase, and Web of Science were searched for studies on HNC patients with ablative and fibula-free flap (FFF) reconstruction surgeries and radiotherapy (RTX). Primary outcomes included treatment sequence, implant survival rates, and RTX dose. Of 661 studies, 20 studies (617 implants, 199 patients) were included. Pooled survival rates for implants receiving >60 Gy RTX were significantly lower than implants receiving < 60 Gy (82.8% versus 90.1%, P =0.035). Placement >1 year after RTX completion improved implant survival rates (96.8% versus 82.5%, P =0.001). Implants receiving pre-placement RTX had increased survival with RTX postablation versus before (91.2% versus 74.8%, P <0.001). One hundred seventy-seven implants were placed only in FFF with higher survival than implants placed in FFF or native bone (90.4% versus 83.5%, P =0.035). Radiotherapy is detrimental to implant survival rates when administered too soon, in high doses, and before tumor resection. A novel evidence-based clinical decision-making algorithm was presented for utilization when determining the optimal treatment order for HNC patients. The overall survival of dental prostheses is acceptable, reaffirming their role as a key component in rehabilitating HNC patients. Considerations must be made regarding RTX dosage, timing, and implant location to optimize survival rates and patient outcomes for improved functionality, aesthetics, and comfort.

Peri-implant health after microvascular head and neck reconstruction-A retrospective analysis

INTRODUCTION

Prosthodontic rehabilitation after reconstruction with microvascular revascularized free flaps following ablative tumor surgery is challenging due to the altered anatomical and functional conditions. The aim of this retrospective study was to determine whether the type of graft and the type of peri-implant tissue have an effect on peri-implant inflammatory parameters and implant survival.

MATERIALS AND METHODS

Patients who received a free flap reconstruction with subsequent implant-prosthetic rehabilitation between 2010 and 2022 were retrospectively included. The primary outcome variable was the probing depth (PPD) at a minimum of 1 year after completion of prosthetic restoration. Predictive variables were type of free flap, emergence profile, and history of radiation.

RESULTS

Seventy-one patients after free flap reconstruction were included in the analysis. At a minimum of 24 months after implant insertion the primary outcome, PPD showed no clinically relevant differences between the types of free flaps used. The emergence profile through a skin island resulted in an increase in BOP compared to native mucosa in the descriptive analysis (p-value > .05). The analysis showed a 5-year implant survival of 96.2% (95% CI: 0.929-0.996) in cases without irradiation and 87.6% (95% CI: 0.810-0.948) with irradiation of the region evaluated (p-value .034).

CONCLUSION

Flap and associated soft tissue type had no significant effect on 5-year implant survival or peri-implant inflammatory parameters. However, the large heterogeneity of the patient population indicates that further prolonged studies are required for a more differentiated assessment of the long-term success.

Effectiveness of dental implants in patients undergoing radiotherapy for head and neck cancer: An umbrella review

OBJECTIVE

The objective of this overview is to evaluate the effectiveness of dental implants placed in patients who underwent radiotherapy for the treatment of head and neck cancer, as well as to assess the methodological quality of the included systematic reviews.

METHODS

The study was conducted in four PubMed, Lilacs, Dare Cochrane and Google Scholar databases until July 2022, using the descriptors "Radiotherapy," "Dental implants," and "Head and Neck Cancer."

RESULTS

958 studies were found in the initial search and after applying the inclusion and exclusion criteria, fifteen systematic reviews were selected to compose this overview and had their methodological quality evaluated by the AMSTAR 2 tool.

RESULTS

24,996 implants in 5487 patients were evaluated with a rate of success rate of 86.2% in patients who underwent radiotherapy and 95.2% in patients who did not undergo radiotherapy. Only one of the systematic reviews was of high quality according to AMSTAR 2.

CONCLUSION

Oral rehabilitation with dental implants in patients with a history of head and neck cancer undergoing radiotherapy is a valid therapy. However, given the level of evidence found, further studies with better design are necessary to provide greater confidence in the clinical decision.

Survival of osseointegrated implants in head and neck cancer patients submitted to multimodal treatment: a systematic review and meta-analysis

PURPOSE

To investigate the survival rate in implants placement in irradiated and non-irradiated bone in patients undergoing head and neck cancer (HNC) treatment. We focused on the consequences of the main complications, such as osteoradionecrosis and peri-implantitis.

METHODS

An electronic search conducted by PRISMA protocol was performed. Full texts were carefully assessed, and data were assimilated into a tabular form for discussion and consensus among the expert panel. The quality assessment and the risk of bias are verified by Joanna Briggs Institute checklist (JBI) and The Newcastle-Ottawa Scale (NOS), and Risk of Bias in Non-Randomized Studies of Interventions (ROBINS-I) assessment tool.

RESULTS

A total of 452 records were identified in the based on our PICOs strategy and after screening, 19 articles were included in the descriptive analysis of the review. Totaling 473 implants placed in irradiated and non-irradiated bone, and 31.6% of the patients were over 60 years of age. 57.9%) performed implant placement in a period of 12 months or more after the ending of radiotherapy. Only 5 studies had a follow-up period longer than 5 years after implant placement, of which three were used for the meta-analysis. In the meta-analysis of 5-year survival rate, analysis of implants in irradiated bone was assessed; a random effect model was used and a weighted proportion (PP) of 93.13% (95% CI: 87.20-99.06; p < 0.001), and in the 5-year survival rate, analysis of implants in non-irradiated bone was analysed; a fixed effect model was used and a weighted proportion (PP) of 98.52% survival (95% CI: 97.56-99.48, p < 0.001).

CONCLUSIONS

Survival rates of implants placed in irradiated bone are clinically satisfactory after a follow-up of 5 years, with a fewer percentage than in implants placed in non-irradiated bone after metanalyses performed.

Indications and surgical technique for distraction osteogenesis of the alveolar bone for augmentation prior to insertion of dental implants

When bone is limited, short, ultra-short, or narrow implants help to restore oral rehabilitation with an acceptable long-term outcome. This becomes more difficult with severe vertical bone loss. Guided bone regeneration, onlay block transplantation, or sandwich osteotomy have been established to build up these defects. The alternative to the alveolar distraction osteogenesis (ADO) has only been established in some centers, with a standardized protocol. On the one hand, ADO is a biological procedure that allows almost a "restitutio ad integrum" when building up hard and soft tissue. On the other hand, there are clear indications, limitations, and complications of the procedure in the literature. In addition to the literature, concept of Tissue Regeneration by Alveolar Callusdistraction Cologne (TRACC), which has been practiced successfully for over two decades, will be presented for different indications.

Clinical outcomes of dental implants in head and neck cancer patients: An overview

OBJECTIVE

The aim of this study was to evaluate the clinical outcomes of dental implants (DIs) in patients with head and neck cancer (HNC) treated with radiotherapy (RT), isolated chemotherapy, or bone modifying agents (BMAs).

STUDY DESIGN

This study was registered in the Prospective Register of Systematic Reviews (CRD42018102772); conducted via the Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist; and based on PubMed, Scopus, Embase, Cochrane Library, Web of Science, and gray literature searches. The selection of studies was performed in 2 phases by 2 independent reviewers. The risk of bias (RoB) was assessed by the Measurement Tool to Assess the Methodological Quality of Systematic Reviews 2.

RESULTS

Twenty systematic reviews were included in the qualitative analysis. The majority scored as having high RoB (n = 11). Primary DIs placement in the mandible of patients with HNC subjected to RT doses <50 Gy was associated with better survival rates.

CONCLUSIONS

The placements of DIs could be considered safe in patients with HNC in sites of alveolar bone that received RT (≤5000 Gy); however, no conclusions could be made in patients with cancer managed by chemotherapy or BMAs. Due to the heterogeneity of studies included, the recommendation for DIs placement in patients with cancer should be carefully considered. Future better controlled randomized clinical trials are required to provide enhanced clinical guidelines for best patient care.

Application of a vascularized bone free flap and survival rate of dental implants after transplantation: A systematic review and meta-analysis

PURPOSE

As maxillofacial surgical techniques have advanced, vascularized bone free flap transplantation has become the standard treatment for repairing maxillofacial defects. In this meta-analysis, we summarize the survival rates of implants after VBFF surgery for maxillary and mandibular reconstructions and investigate the factors affecting patient outcomes.

METHODS

The PubMed, Embase, and Wanfang databases were searched up to May 31, 2022. The results of the treatment effect are presented as the risk ratio or odds ratio, using 95% confidence intervals. Statistical significance was calculated at α = 0.05 (two-tailed z tests).

RESULTS

35 studies were included in our analysis. The results revealed a 3-year and 5-year implant survival rate of 95.2% and 85.4% in VBFFs, respectively. The location of jaw defects (maxilla or mandible) or timing of implantation was not found to have a statistically significant influence on the survival rate. However, statistically significant differences were observed in the failure of implants placed in irradiated bone tissue.

CONCLUSIONS

Statistically significant differences were not found in the implant survival rate between simultaneous and delayed implantation, or between maxillary and mandibular defects. However, dental implants placed in irradiated flaps tended to have a lower survival rate than those surgically placed in non-irradiated flaps.

The dose-dependent impact of γ-radiation reinforced with backscatter from titanium on primary human osteoblasts

In head and neck cancer patients receiving dental implants prior to radiotherapy, backscatter from titanium increases the radiation dose close to the surface, and may affect the osseointegration. The dose-dependent effects of ionizing radiation on human osteoblasts (hOBs) were investigated. The hOBs were seeded on machined titanium, moderately rough fluoride-modified titanium, and tissue culture polystyrene, and cultured in growth- or osteoblastic differentiation medium (DM). The hOBs were exposed to ionizing γ-irradiation in single doses of 2, 6 or 10 Gy. Twenty-one days post-irradiation, cell nuclei and collagen production were quantified. Cytotoxicity and indicators of differentiation were measured and compared to unirradiated controls. Radiation with backscatter from titanium significantly reduced the number of hOBs but increased the alkaline phosphatase activity in both types of medium when adjusted to the relative cell number on day 21. Irradiated hOBs on the TiF-surface produced similar amounts of collagen as unirradiated controls when cultured in DM. The majority of osteogenic biomarkers significantly increased on day 21 when the hOBs had been exposed to 10 Gy, while the opposite or no effect was observed after lower doses. High doses reinforced with backscatter from titanium resulted in smaller but seemingly more differentiated subpopulations of osteoblasts.

Cirurgia Guiada para Instalação de Implantes em Paciente Submetido à Radioterapia em Região de Cabeça e Pescoço

Introdução: O uso dos implantes osseointegrados para reabilitação de pacientes com dificuldade de adaptação de próteses convencionais mostra-se mais frequente a cada dia. Um grande grupo candidato à reabilitação com essa modalidade são os pacientes tratados para as neoplasias de cabeça e pescoço (CP). A irradiação na região de CP pode ser limitante para a instalação de implantes, porém a literatura apresenta evidências de técnicas e planejamentos favoráveis ao procedimento nesse grupo de pacientes. As técnicas menos traumáticas para intervenções na cavidade oral devem ser avaliadas, e os guias cirúrgicos para colocação de implantes podem ser aliados nesses procedimentos. Relato do caso: Paciente do sexo feminino, 64 anos, tratada com cirurgia, quimioterapia e radioterapia em cavidade oral para um carcinoma espinocelular (CEC) em língua e, em um segundo momento, diagnosticada e tratada com cirurgia para CEC em região de rebordo alveolar maxilar esquerdo por meio de hemipalatecmia, necessitava de reabilitação com implantes osseointegrados na região onde havia sido tratada com radiação primariamente. Realizou-se a cirurgia de colocação dos implantes com a tecnologia guiada para acarretar o mínimo trauma às estruturas bucais. Conclusão: O procedimento cirúrgico foi executado com sucesso. Atualmente, aguarda-se o período de osseointegração para a posterior reabilitação protética.

Survival of Dental Implants on Irradiated Jaws: A Systematic Review and Meta-analysis

Objectives

Dental implants play a significant role in functional rehabilitation of the oral cavity after debilitating jaw surgeries for oral cavity cancers followed by radiotherapy.

Design

The meta-analysis was done using Preferred Reporting Items for Systematic Review (PRISMA) guidelines published from January 1947 till August 2020. Twenty three articles consisting of 1246 participants with 4838 implants were included in our analysis.

Results

The mean age of the included participants was 51.4 years. 2186 and 1685 implants were placed on irradiated and non-irradiated jaws and showed a success rate of 82.47% and 89.37% respectively. Correspondingly, publication bias of p value = 0.2129 and p-value = 0.6525 was found by Egger's and Begg's test respectively for pooled data of 16 studies. The implant success rate of 70.4% on maxillary bone and 94.5% were observed on mandibular bone. Timing of implant placement and its influence on survival rate have resulted in a 75.5% survival rate of dental implants when placed primarily in comparison with 87.7% on delayed placement. The waiting interval of 14 months in delayed implant placement has shown better results.

Conclusion

Presence of radiotherapy does not play a significant role in the success rate of dental implants in oral cavity cancers. However, delayed implant placement may have a better chance of survival.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12663-022-01686-6.

Influence of Radiotherapy on Ossification of Vascularized Osseous Reconstruction of the Jaw: A Radiological Retrospective Cohort Study Based on Panoramic Radiographs

Background: The aim of this study was to evaluate the impact of irradiation and time of irradiation on the ossification of jaws reconstructed with free bone grafts. Methods: In total, 100 reconstructions of the jaw were retrospectively evaluated for ossification between bone segments by two raters based on postoperative panoramic radiographs (immediate postOP, approximately 6, 12 and 24 months follow-up). Three subgroups were divided according to the time of irradiation: preoperative radiation therapy (n = 41), postoperative radiation therapy (n = 26) and patients without any radiation therapy (n = 33) as the control group. Ossification time and influencing factors were documented. Results: The fastest ossification with a median of 304 ± 37 days was observed (p < 0.001) in the nonirradiated control group. No significant difference (p = 0.087) in ossification was found between the pre- (447 ± 136 days) and postoperative (510 ± 112 days) radiation groups. Ossification between two graft segments (336 ± 38 days) showed significantly (p < 0.001) faster ossification than between the original and grafted bone (448 ± 85 days). Moreover, closer initial contact between the segments resulted in faster ossification (p < 0.001). When analyzing cofactors, tobacco consumption was the only negative factor aggravating ossification (p = 0.006). Conclusion: Head and neck radiation corresponded with the impaired and prolonged ossification of jaw reconstructions with free bone grafts. There was no difference in ossification if radiotherapy was performed before or after reconstructive surgery. A close bony contact was particularly important for ossification between the original and grafted bone.

Influence of radiotherapy on dental implants placed in individuals before diagnosed with head and neck cancer: focus on implant-bed-specific radiation dosage

OBJECTIVES

The influence of radiotherapy on implants placed before diagnosed as head and neck cancer (HNC) is a potentially informative but poorly explored topic. The aims of this study were to investigate the influence of implant-bed-specific radiation dose on dental implants and to evaluate the impact of these implants on radiation dosimetry.

MATERIAL AND METHODS

We conducted a retrospective study with 58 irradiated patients that received dental implant restorations before undergoing radiation treatment for HNC. The radiological success rate and the peri-implant bone resorption values were measured radiographically at 1 and 3 years after radiotherapy. Patients with no implants matching tumor site and stage served as a control group (n = 58).

RESULTS

The median implant-bed-specific radiation dose was 40.3 Gy, which was significantly lower than tumor bed 62.4 Gy. An implant-bed-specific radiation dose higher than 40.0 Gy showed a significantly decreased radiologic success rate when compared to lower doses. Finally, evaluation of the radiation treatment plans revealed similar radiation hot spots in the test group of patients with implants and those of the control group.

CONCLUSION

Our study confirms that radiotherapy negatively worsens peri-implant bone resorption, especially for implant-bed-specific dose more than 40 Gy, and the presence of implants within the radiation fields does not alter radiation dosimetry. The findings could be clinically informative to both surgeons and radio-oncologists.

CLINICAL RELEVANCE

The interactions between radiotherapy and implants placed prior to radiotherapy treatment remain a largely unexplored topic. Based on the analysis of 3-dimensional modulated radiation plans, this study demonstrates the impact of implant-bed-specific radiation dose on marginal bone resorption of implants placed pre-radiation and considers the influence of these implants on radiation dosimetry.

REGISTRATION NUMBER

CHICTR2100051923: ( http://www.chictr.org.cn/usercenter.aspx ).

Survival of dental implants and occurrence of osteoradionecrosis in irradiated head and neck cancer patients: a systematic review and meta-analysis

OBJECTIVES

This systematic review assesses dental implant survival, calculates the incidence rate of osteoradionecrosis, and evaluates risk factors in irradiated head and neck cancer patients.

MATERIALS AND METHODS

Various databases (e.g., Medline/Embase using Ovid) and gray literature platforms were searched using a combination of keywords and subject headings. When appropriate, meta-analysis was carried out using a random effects model. Otherwise, pooled analysis was applied.

RESULTS

A total of 425 of the 660 included patients received radiotherapy. In total, 2602 dental implants were placed, and 1637 were placed in irradiated patients. Implant survival after an average follow-up of 37.7 months was 97% (5% confidence interval, CI 95.2%, 95% CI 98.3%) in nonirradiated patients and 91.9% (5% CI 87.7%, 95% CI: 95.3%) after an average follow-up of 39.8 months in irradiated patients. Osteoradionecrosis occurred in 11 cases, leading to an incidence of 3% (5% CI 1.6%, 95% CI 4.9%). The main factors impacting implant survival were radiation and grafting status, while factors influencing osteoradionecrosis could not be determined using meta-analysis.

CONCLUSION

Our data show that implant survival in irradiated patients is lower than in nonirradiated patients, and osteoradionecrosis is-while rare-a serious complication that any OMF surgeon should be prepared for. The key to success could be a standardized patient selection and therapy to improve the standard of care, reduce risks and shorten treatment time.

CLINICAL RELEVANCE

Our analysis provides further evidence that implant placement is a feasible treatment option in irradiated head and neck cancer patients with diminished oral function and good long-term cancer prognosis.

Osseointegrated implant survival, success and prosthodontic outcomes in composite free flaps: A 10-year retrospective cohort study

OBJECTIVES

To evaluate implant survival, success and prosthodontic outcomes in a variety of composite free flaps.

MATERIAL AND METHODS

A retrospective analysis of patient records was used for data collection of implants placed into flaps. Free flap donor sites included fibula, iliac crest, scapula, medial femoral condyle and radial forearm. Kaplan-Meier survival curves were used to estimate survival. Cox regression was used to assess variables affecting survival, and binary logistic regression was utilised to determine effect of variables on prosthodontic outcomes.

RESULTS

There were 150 implants placed into 45 fibula, 98 implants into 29 iliac crest, 62 implants into 22 scapula, 6 implants into 3 medial femoral condyle and 2 implants in radial forearm composite free flaps. There was no difference in survival or success between or within the various flaps. Active smoking, increasing age, male gender and radiotherapy were associated with implant failure. Of patients completing prosthodontic rehabilitation, 93% were successful. There was no difference in likelihood of failure between different flap types. Fixed implant-supported dentures were associated with poor oral hygiene compared with removable designs (OR2.9, 95%CI 1.1-7.8, p = .03).

CONCLUSIONS

There is adequate survival and success of implants in common flaps. Caution is required when planning implants in patients exposed to radiotherapy and smokers. Ability to maintain adequate oral hygiene is an important prosthetic design consideration.

Clinical long-term and patient-reported outcomes of dental implants in oral cancer patients

BACKGROUND AND PURPOSE

The aim of this clinical study was to investigate the clinical long-term and patient-reported outcome of dental implants in patients with oral cancer. In addition, analysis of the influence of radiation therapy, timing of implant insertion, and augmentation procedures on implant survival was performed.

MATERIAL AND METHODS

This retrospective study investigated the clinical outcome of 711 dental implants in 164 oral cancer patients, inserted by experienced surgeons of the Department of Oral and Maxillofacial Surgery, University Medical Center Mainz, Germany. Oral health-related quality of life (OHRQoL) was evaluated.

RESULTS

Cumulative 5-year and 10-year implant survival rates for all included implants were 87.3% and 80.0%. Implants placed straight after ablative surgery (primary implant placement) and implants placed after completing the oncologic treatment (secondary implant placement) showed a comparable implant survival (92.5% vs. 89.5%; p = 0.635). Irradiation therapy had no significant influence on implant survival of secondary placed implants (p = 0.929). However, regarding implant site (native bone vs. augmented bone) and radiation therapy (non-irradiated bone vs. irradiated bone), implants inserted in irradiated bone that received augmentation procedures showed a statistically significant lower implant survival (p < 0.001). Patients reported a distinct improvement in OHRQoL.

CONCLUSIONS

Promising long-term survival rates of dental implants in patients after treatment of oral cancer were seen. In addition, patients benefit in form of an improved OHRQoL. However, bone augmentation procedures in irradiated bone may result in an impaired implants' prognosis.

Outcomes of osseointegrated implants in patients with benign and malignant pathologies of the head and neck: a 10-year single-centre study

The surgical management of head and neck pathologies involving the maxilla and mandible results in significant functional and aesthetic deficits, and ultimately reduced quality of life. Composite free flaps used for reconstruction address many of these deficits and create a foundation for the use of osseointegrated implants to support prosthetic replacement of the dentition. There are few comparative studies examining outcomes of implants in native and reconstructed bone in head and neck cancer patients. The aim of this retrospective cohort study was to compare survival rates and the effects of risk factors between implants placed in native and reconstructed bone. The Kaplan-Meier method estimated cumulative 1- and 5-year implant survival rates of 99.5% and 95% for native bone and 96% and 88% for reconstructed bone. Multivariate Cox regression found an increased risk of implant failure in reconstructed bone (hazard ratio (HR) 9.9, 95% confidence interval (CI) 3.4-29.7, P<0.001). Subgroup analysis of the cohorts found an increased risk of failure in the reconstructed group associated with radiotherapy (HR 6.4, 95% CI 1.8-22.3, P=0.004), current smoking (HR 23.2, 95% CI 2.7-198.6, P=0.004), and previous smoking (HR 9.0, 95% CI 1.1-71.9, P=0.038). There was no effect in the native bone group. Implants placed into reconstructed bone had higher rates of failure, and smoking status and radiotherapy increased the risk of implant failure.

Retrospective long-term clinical evaluation of implant-prosthetic rehabilitations after head and neck cancer therapy

OBJECTIVE

To assess clinical and patient-reported outcomes of implant-prosthetic rehabilitations in patients with a history of head-neck cancer (HNC), treated with tumor resection without (TR) or with adjuvant radiotherapy (TR/RT). A healthy cohort rehabilitated with the same reconstructive protocols served as control group (C).

MATERIALS AND METHODS

A total of 28 women and 29 men were considered in the present retrospective study. Participants received 322 implants, finally supporting 79 prosthetic reconstructions. Primary outcome was the assessment of implant and prosthetic survival rates. Furthermore peri-implant soft tissue parameters (attached peri-implant mucosa, AM; modified bleeding and plaque indices, mBI/mPI; probing depth, PD) and prosthetic technical complications were documented. Patient-reported outcome measures (PROMs) by means of visual analog scales (VAS) and the Oral Health Impact Profile German 14 form (OHIP G14) were collected. For statistical purposes Chi-square and Mann-Whitney-U-Test were adapted.

RESULTS

After a mean follow-up of 81.2 ± 50.3 months, implant survival rate was 98.1% (HNC-TR), 98.2% (HNC-TR/RT) and 100.0% (C), respectively (four implants failed in the HNC groups). HNC-TR/RT showed significant higher mPI and mBI compared to C. Within HNC-TR/RT, vestibuloplasty significantly reduced mBI and PD values. No failures occurred at the prosthetic level. Overall, higher VAS scores were reported for bar- compared with Locator-retained prostheses. Furthermore, increased OHIP G14 values resulted for HNC-TR/RT.

CONCLUSIONS

High survival rates on implant and prosthetic level were observed. The use of soft tissue grafts resulted in stabilization of the peri-implant mucosa in irradiated patients. In terms of retention and chewing ability, participants preferred bars over Locator attachments.

Midface Reconstruction: Planning and Outcome

Reconstruction of the complex anatomy and aesthetics of the midface is often a challenge. A careful understanding of this three-dimensional (3D) structure is necessary. Anticipating the extent of excision and its planning following oncological resections is critical.

In the past over two decades, with the advances in microsurgical procedures, contributions toward the reconstruction of this area have generated interest. Planning using digital imaging, 3D printed models, osseointegrated implants, and low-profile plates, has favorably impacted the outcome. However, there are still controversies in the management: to use single composite tissues versus multiple tissues; implants versus autografts; vascularized versus nonvascularized bone; prosthesis versus reconstruction.

This article explores the present available options in maxillary reconstruction and outlines the approach in the management garnered from past publications and experiences.

Medically Complex Dental Implant Patients: Controversies About Systemic Disease and Dental Implant Success/Survival

Advances in dental implant therapy have created choices to enhance the expectations of dental practitioners and their patients with respect to oral rehabilitation at any age after childhood and regardless of, in most cases, medical disabilities. The medical status of the patient however can significantly influence the success rate of dental implant therapy. This article applies the hierarchy of scientific evidence ranging from case reports, retrospective, prospective cohort investigations, systematic reviews, and meta-analyses criteria in order to determine whether dental implant placement in medically compromised patients yields any detrimental sequelae.

Systematic review and pooled analysis of survival rates, success, and outcomes of osseointegrated implants in a variety of composite free flaps

The aim of this review was to provide an update on survival rates of osseointegrated implants into common composite free flaps used for maxillary and mandibular reconstructions and identify factors affecting outcomes. PubMed, Medline, Embase, and Cochrane databases were searched. Included studies reported implant survival by flap type. Results were pooled and survival was estimated with the Kaplan-Meier method. Variables affecting survival were assessed using Cox regression. Thirty-two of the 2631 articles retrieved were included, totaling 2626 implants placed into fibula, iliac crest, scapula, and radial forearm free flaps. Pooled survival showed 94% 5-year survival of implants in fibula and iliac crest with no difference between groups (P = .3). Factors effecting survival included radiotherapy (HR 2.3, 95% CI 1.2-4.6, P = .027) and malignant disease (HR 2.2, 95%CI 1.6-3.1, P < .001). Implant survival appears adequate across common flap types; however, there are limited numbers reported in less common flaps.

Mandibular dental implant placement immediately after teeth removal in head and neck cancer patients

BACKGROUND

Little is known about immediate implant placement in head and neck cancer patients. We studied implant survival and functional outcomes of overdentures fabricated on implants placed immediately after removal of the lower dentition during ablative surgery or preceding primary radiotherapy (RT).

METHODS

Inclusion criteria were primary head and neck cancer, dentate lower jaw, and indication for removal of remaining teeth. Two implants to support a mandibular overdenture were placed immediately after extraction of the dentition during ablative surgery, or prior to starting primary radiotherapy. Standardized questionnaires and clinical assessments were conducted (median follow-up 18.5 months, IQR 13.3).

RESULTS

Fifty-eight implants were placed in 29 patients. Four implants were lost (implant survival rate 93.1%). In 9 patients, no functional overdenture could be made. All patients were satisfied with their dentures.

CONCLUSIONS

Combining dental implant placement with removal of remaining teeth preceding head neck oncology treatment results in a favorable treatment outcome.

Quality Assessment of Systematic Reviews on Platform-Switching vs Platform-Matched Implants: An Overview

The objective of this study was to perform a quality analysis of systematic reviews with meta-analyses that focused on the comparison of platform-switching (implant-abutment mismatching) and platform-matched (PM) implants. The assessment of multiple systematic reviews (AMSTAR) and Glenny (Checklist) Scales were used to qualify the studies. PubMed, Scientific Electronic Library Online (SciELO), Web of Science (formerly ISI Web of Knowledge), and Cochrane databases were searched, by topic, for systematic reviews on dental implants with switching platforms. A total of 8 systematic reviews, including 7 studies with meta-analyses, were selected. The AMSTAR scale indicated a high (n = 6) to moderate (n = 2) score for the included studies. The quantitative analysis indicated that platform-switching implants preserved more bone tissue when compared with platform-matched implants (6 meta-analyses; P < .001, smaller mean difference: -0.29 mm, 95% CI: -0.38, -0.19 and greater mean difference: -0.49 mm, 95% CI: -0.73, -0.26). Quantitative analysis based on 7 systematic reviews with meta-analysis indicated positive peri-implant bone preservation for implants restored with an implant-abutment mismatching (PSW). Further, there is evidence to improve the design of current systematic reviews. Future systematic reviews in this thematic area should consider searches in gray literature and different databases and include only randomized controlled clinical studies.

Postimplantation radiation therapy in head and neck cancer patients: Literature review

There is no recommendation regarding the timing for implant surgery in patients with head and neck cancer (HNC) who require postoperative radiation therapy (RT). This systematic review focused on the literature about the outcomes of implants placed during ablative surgery in patients with HNC who underwent postoperative RT. Implants placed after radiation therapy and implants placed in reconstructed jaws were excluded. Four comparative studies involving 755 native mandible primary implants were analyzed. The survival rate with postimplantation RT was 89.6% vs 98.6% in patients with no additional radiation. The overall success of implant-retained overdenture in patients with RT performed postimplantation was 67.4% vs 93.1% in patients with implant surgery that was carried out 1 year after the completion of radiation therapy. Only five cases of osteoradionecrosis (ORN) of the jaw were reported. The outcomes for implant survival rates appear to be positive for irradiated implants.

The etiology of hard- and soft-tissue deficiencies at dental implants: A narrative review

OBJECTIVE

The objective of the present paper was to review factors and conditions that are associated with hard and soft-tissue deficiencies at implant sites.

IMPORTANCE

Hard- and soft-tissue deficiencies at dental implants are common clinical findings. They can lead to complications and compromise implant survival and, hence, may require therapeutic interventions. It is, therefore, important to understand the etiology of hard and soft-tissue deficiencies. Based on this understanding, strategies should be developed to correct hard and soft-tissue deficiencies with the aim of improving clinical outcomes of implant therapy.

FINDINGS

A large number of etiological factors have been identified that may lead to hard and soft-tissue deficiencies. These factors include: 1) systemic diseases and conditions of the patients; 2) systemic medications; 3) processes of tissue healing; 4) tissue turnover and tissue response to clinical interventions; 5) trauma to orofacial structures; 6) local diseases affecting the teeth, the periodontium, the bone and the mucosa; 7) biomechanical factors; 8) tissue morphology and tissue phenotype; and 9) iatrogenic factors. These factors may appear as an isolated cause of hard and soft-tissue defects or may appear in conjunction with other factors.

CONCLUSIONS

Hard- and soft-tissue deficiencies at implant sites may result from a multitude of factors. They encompass natural resorption processes following tooth extraction, trauma, infectious diseases such as periodontitis, peri-implantitis, endodontic infections, growth and development, expansion of the sinus floor, anatomical preconditions, mechanical overload, thin soft tissues, lack of keratinized mucosa, malpositioning of implants, migration of teeth, lifelong growth, and systemic diseases. When more than one factor leading to hard and/or soft-tissue deficiencies appear together, the severity of the resulting condition may increase. Efforts should be made to better identify the relative importance of these etiological factors, and to develop strategies to counteract their negative effects on our patient's wellbeing.

The etiology of hard- and soft-tissue deficiencies at dental implants: A narrative review

OBJECTIVE

The objective of the present paper was to review factors and conditions that are associated with hard and soft-tissue deficiencies at implant sites.

IMPORTANCE

Hard- and soft-tissue deficiencies at dental implants are common clinical findings. They can lead to complications and compromise implant survival and, hence, may require therapeutic interventions. It is, therefore, important to understand the etiology of hard and soft-tissue deficiencies. Based on this understanding, strategies should be developed to correct hard and soft-tissue deficiencies with the aim of improving clinical outcomes of implant therapy.

FINDINGS

A large number of etiological factors have been identified that may lead to hard and soft-tissue deficiencies. These factors include: 1) systemic diseases and conditions of the patients; 2) systemic medications; 3) processes of tissue healing; 4) tissue turnover and tissue response to clinical interventions; 5) trauma to orofacial structures; 6) local diseases affecting the teeth, the periodontium, the bone and the mucosa; 7) biomechanical factors; 8) tissue morphology and tissue phenotype; and 9) iatrogenic factors. These factors may appear as an isolated cause of hard and soft-tissue defects or may appear in conjunction with other factors.

CONCLUSIONS

Hard- and soft-tissue deficiencies at implant sites may result from a multitude of factors. They encompass natural resorption processes following tooth extraction, trauma, infectious diseases such as periodontitis, peri-implantitis, endodontic infections, growth and development, expansion of the sinus floor, anatomical preconditions, mechanical overload, thin soft tissues, lack of keratinized mucosa, malpositioning of implants, migration of teeth, lifelong growth, and systemic diseases. When more than one factor leading to hard and/or soft-tissue deficiencies appear together, the severity of the resulting condition may increase. Efforts should be made to better identify the relative importance of these etiological factors, and to develop strategies to counteract their negative effects on our patient's wellbeing.

miR-34a promotes bone regeneration in irradiated bone defects by enhancing osteoblastic differentiation of mesenchymal stromal cells in rats

Background

Radiation exposure negatively affects the regenerative ability and makes reconstruction of bone defects after tumor section difficult. miR-34a is involved in radiation biology and bone metabolism. The aim of this study was to investigate whether miR-34a could contribute to bone regeneration in irradiated bone defects.

Methods

The expression of miR-34a was analyzed during the osteoblastic differentiation of irradiated BMSCs and bone formation in irradiated bone defects. miR-34a mimics and miR-34a inhibitor were used to upregulate or suppress the expression of miR-34a in BMSCs irradiated with 2 or 4 Gy X-ray radiation. In vitro osteogenesis and subcutaneous osteogenesis were used to assess the effects of miR-34a on the osteogenic ability of radiation-impaired BMSCs. Collagen-based hydrogel containing agomiR-34a or antagomiR-34a were placed into the 3-mm defects of irradiated rat tibias to test the effect of miR-34a on bone defect healing after irradiation.

Results

miR-34a was upregulated in the process of bone formation after irradiation. Transfecting radiation-impaired BMSCs with miR-34a mimics enhanced their osteoblastic differentiation in vitro by targeting NOTCH1. Overexpression of miR-34a enhanced the ectopic bone formation of irradiated BMSCs. In situ delivery of miR-34a promoted bone regeneration in irradiated bone defects.

Conclusions

miR-34a promoted the osteoblastic differentiation of BMSCs and enhanced the ectopic bone formation after irradiation. miR-34a promoted bone defect healing in irradiated rat tibias. miR-34a-targeted therapy might be a promising strategy for promoting the reconstruction of bone defects after radiotherapy.

Electronic supplementary material

The online version of this article (10.1186/s13287-019-1285-y) contains supplementary material, which is available to authorized users.

Ability to Propose Optimal Prosthetic Rehabilitation can be Improved by Discussion between the Dentist and Radiation Oncologist Regarding Upstream Dosimetry

Objective Improvement of dental rehabilitation for patients who have undergone radiation therapy requires knowledge of the dose in the maxillary and mandible bones.

Materials and Methods Forty-three patients with head and neck cancers underwent evaluation for dental rehabilitation before radiation treatment dosimetry. The delivered dose to the maxilla and mandible was determined. From the dose data in the literature, three levels of risk of implant failure were defined. According to the delivered doses, the authors calculated the percentage of patients who could be fully rehabilitated with an implant, as proposed by the dentist before radiation planning.

Results Before dosimetry calculation, all of the completely edentulous arches and 94 partially edentulous (PESs) sextants could be optimally rehabilitated. After dose calculation, among the 14 arches of 7 patients who were completely edentulous, according to the mean and maximal delivered doses, 11 arches (78.6%) and 7 arches (50%) could receive an optimal prosthesis, respectively. For the three patients, who were PESs but with one arch that was completely edentulous, according to the mean and maximal delivered doses, one arch for each dose condition could receive an optimal prosthesis. Among the 94 PESs sextants, according to the mean and maximal delivered doses, 41 (43.6%) and 24 (25.5%) sextants could receive an optimal prosthesis, respectively.

Conclusion By determining the sites of implantation before dosimetry, the radiation oncologist could shield specified areas, potentially improving the possibilities for dental rehabilitation. The dialogue between the dentist and the radiation oncologist can improve the possibilities for implants and decrease the risk of unsafe implantation.

Are There Contraindications for Placing Dental Implants?

There are few absolute contraindications to dental implant placement. Relative contraindications include cognitive decline, American Society of Anesthesiology patient status IV or higher categories, or medical conditions that may jeopardize the life or lifespan of the patient. Precautions for placing dental implants should be viewed with respect to the evidence-based exposures that can contribute to risk of failure, including but not limited to local, behavioral, and medical factors. Risk for dental implant failure increases in association with (1) past history of periodontal disease, (2) bruxism, (3) smoking, and (4) radiation therapy.

Can gamma irradiation during radiotherapy influence the metal release process for biomedical CoCrMo and 316L alloys?

The extent of metal release from implant materials that are irradiated during radiotherapy may be influenced by irradiation-formed radicals. The influence of gamma irradiation, with a total dose of relevance for radiotherapy (e.g., for cancer treatments) on the extent of metal release from biomedical stainless steel AISI 316L and a cobalt-chromium alloy (CoCrMo) was investigated in physiological relevant solutions (phosphate buffered saline with and without 10 g/L bovine serum albumin) at pH 7.3. Directly after irradiation, the released amounts of metals were significantly higher for irradiated CoCrMo as compared to nonirradiated CoCrMo, resulting in an increased surface passivation (enhanced passive conditions) that hindered further release. A similar effect was observed for 316L showing lower nickel release after 1 h of initially irradiated samples as compared to nonirradiated samples. However, the effect of irradiation (total dose of 16.5 Gy) on metal release and surface oxide composition and thickness was generally small. Most metals were released initially (within seconds) upon immersion from CoCrMo but not from 316L. Albumin induced an increased amount of released metals from AISI 316L but not from CoCrMo. Albumin was not found to aggregate to any greater extent either upon gamma irradiation or in the presence of trace metal ions, as determined using different light scattering techniques. Further studies should elucidate the effect of repeated friction and fractionated low irradiation doses on the short- and long term metal release process of biomedical materials. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 2673-2680, 2018.

Increasing the Stability of Dental Implants: the Concept of Osseodensification

One of the most important factors that affect osseointegration is the primary stability of the implant. Dental implants inserted at the posterior region of the maxilla exhibit the lowest success rates as the low density bone in this area often jeopardize rigid fixation of the implant. Many surgical techniques have been developed to increase the primary stability of an implant placed in low density bone, such as bicortical fixation of the implant, undersized preparation of the implant bed and bone condensation by the use of osteotomes. A new promising technique, named osseodensification, has been recently developed that creates an autograft layer of condensed bone at the periphery of the implant bed by the aid of specially designed burs rotating in a clockwise and anti-clockwise direction. The purpose of this review is to emphasize that implant primary stability is strongly influenced by the surgical technique, to quote and briefly analyse the various surgical procedures laying weight to osseodensification procedure.

A new concept for implant-borne dental rehabilitation; how to overcome the biological weak-spot of conventional dental implants?

Background

Every endosseous dental implant is dependent on an adequate amount and quality of peri-implant hard and soft tissues and their fully functional interaction. The dental implant could fail in cases of insufficient bone and soft tissues or due to a violation of the soft to hard tissues to implant shoulder interface with arising of a secondary bone loss.

Method

To overcome this biological weak-spot, we designed a new implant that allows for multi vector endosseous anchorage around the individual underlying bone, which has to be scanned by computed tomography (CT) or Cone beam CT (CBCT) technique to allow for planning the implant. We developed a workflow to digitally engineer this customized implant made up of two planning steps. First, the implant posts are designed by prosthodontic-driven backward planning, and a wireframe-style framework is designed on the individual bony surface of the recipient site. Next, the two pieces are digitally fused and manufactured as a single piece implant using the SLM technique (selective laser melting) and titanium-alloy-powder.

Results

Preoperative FEM-stress-test of the individual implant is possible before it is inserted sterile in an out-patient procedure.

Conclusion

Unlike any other historical or current dental implant protocol, our newly developed “individual patient solutions dental” follows the principle of a fully functional and rigid osteosynthesis technology and offers a quick solution for an implant-borne dental rehabilitation in difficult conditions of soft and hard tissues.

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.