Alberta reconstructive technique (ART): An innovative approach using digital surgical design and simulation in advanced jaw reconstruction with occlusion-based prefabricated vascularized fibular flaps and primary osseointegrated implant installation.

The Alberta reconstructive technique (ART) is an innovative surgical procedure performed on patients undergoing primary jaw resection and reconstruction. The ART procedure was developed in collaboration with the Institute for Reconstructive Sciences in Medicine and the Division of Otolaryngology-Head and Neck Surgery, University of Alberta.

The future of maxillofacial prosthodontics in North America: The role of advanced digital technology and artificial intelligence - A discussion document.

STATEMENT OF PROBLEM: Maxillofacial prosthodontists were advanced digital technology (ADT) adopters early in the new Millennium. The past two decades saw a range of digital enablers emerge including digital imaging (internal and surface), digital surgical planning, digital functional assessment, subtractive and additive manufacturing, navigation, and robotics among others. Artificial Intelligence (AI) is the latest ADT arrival that will be a challenging disruptive technology. ADT has served as a profound change agent in maxillofacial prosthodontics. The intent was to explore the process and level of ADT engagement in maxillofacial prosthodontics. PURPOSE: The purpose was twofold. Firstly, to explore maxillofacial prosthodontic engagement of ADT. Secondly, to develop a discussion document to assist the American Academy of Maxillofacial Prosthetics (AAMP) with establishing a collective awareness and considered opinion on the future of maxillofacial prosthodontics in the digital era. MATERIAL AND METHODS: AAMP member interest in ADT was assessed through analysis of AAMP annual congress programs and publications in the Journal of Prosthetic Dentistry (JPD). The history of the maxillofacial prosthodontic journey to the digital era was undertaken with a selective literature review. The perceptions maxillofacial prosthodontists hold on ADT engagement was assessed through a survey of AAMP members. Developing an understanding of the influence AI was conducted with a review of pertinent literature. RESULTS: From 2011-2020, an annual mean of 38% of papers published in the JPD involved clinical use of ADT. From 2017-2019, 44% of invited presentations at AAMP annual congresses included clinical use of ADT. The journey to the digital era distinguished three periods with formative and consolidation periods influencing the innovation digital era. The AAMP member survey had a 59% response rate and studied 10 domains through 31 questions. Of the respondents, 89% thought ADT important to the future of maxillofacial prosthodontics. CONCLUSIONS: The discussion document will assist the AAMP in developing a collective consciousness and considered opinion on ADT in the future of maxillofacial prosthodontics. Members of the AAMP have a developed interest in clinical applications of ADT. A great challenge is that no formal education, training, or clinical competency requirements for ADT could be identified. Clinical competency requirements are important to prepare maxillofacial prosthodontics for the inevitability of a digital era future. The discussion document poses the fundamental question of whether maxillofacial prosthodontists will remain as passive end users of ADT and AI or will they become engaged knowledge workers that have determined clinical competency in ADT and AI in patient care. Without this knowledge worker role, maxillofacial prosthodontists may experience difficulty being part of the inevitable ADT-AI driven future.

The future of maxillofacial prosthodontics in North America: Part II - A survey.

STATEMENT OF PROBLEM: Head and neck care has been transformed by the introduction of advanced digital technologies that will continue to be important change drivers for maxillofacial prosthodontics. Insight into these changes is important in answering the question of whether maxillofacial prosthodontics is appropriately prepared to contribute effectively to future multidisciplinary care of the head and neck. PURPOSE: The purpose of this survey was to gain insight into the perception of changes experienced by maxillofacial prosthodontists in relation to clinical practice. The findings of this survey may assist the future development of the subspecialty. MATERIAL AND METHODS: An exploratory cross-sectional survey was conducted by using a convenience sample of members of the American Academy of Maxillofacial Prosthetics. The survey considered 10 domains and 31 questions. Fully completed surveys (164) provided a 59% response. Descriptive statistics used percentage responses to reduce and characterize perceptions across respondents. RESULTS: Eighty-four percent of the respondents were from the United States. Results should be interpreted based on this cohort. Respondents reported a change in care delivered over the past 10 years (72%), with the most important causes of change attributed to surgery (60%) and advanced digital technologies (56%). Respondents perceived advanced digital technologies as being central to the future of maxillofacial prosthodontics (89%) and important in attracting younger colleagues (88%). Sixty-three percent believed training programs were not providing adequate education and training in the use of advanced digital technology. CONCLUSIONS: The perception of maxillofacial prosthodontists regarding changes taking place in care delivery was that the most important changes in the past 10 years were attributed to surgery and advanced digital technologies, that persisting pressures related to few institutional positions, that the subspecialty was poorly visible, that remuneration for care was inadequate and referring disciplines did not understand the subspecialty, that advanced digital technologies were considered central to the future of maxillofacial prosthodontics and important to attract younger colleagues to the subspecialty, that barriers to advanced digital technology use included funding for equipment acquisition, institutional funding support, and remuneration for their use in care delivery, and that maxillofacial prosthodontic programs were not providing adequate education and training in advanced digital technologies.

The future of maxillofacial prosthodontics in North America: Part I-Journey to the present.

STATEMENT OF PROBLEM: Understanding how maxillofacial prosthodontists are perceiving changes in head and neck care and the impact of advanced digital technologies on maxillofacial prosthodontics is important. However, no studies could be identified that specifically addressed these subjects. PURPOSE: The purpose of this review of selected literature was to identify issues that guided the development of maxillofacial prosthodontics and the concerns that persist. The review also considered contemporary influences that will affect the future of maxillofacial prosthodontics. The conclusions of the review were used to interpret the results of the exploratory survey reported in Part II. MATERIAL AND METHODS: The review of selected literature was related to the development of maxillofacial prosthodontics in North America between 1950 and 2018. Literature that was considered relevant to the purpose of the review was included. RESULTS: The review yielded 37 references of interest: 34 peer-reviewed publications, 1 guideline, 1 historical publication, and 1 website. Periods in the development of maxillofacial prosthodontics in North America were identified as formation, consolidation, and innovation. CONCLUSIONS: It was concluded that concerns in subspecialty programs and clinical practice had origins in the formation and consolidation periods. These persisting concerns extended into the innovation period. Contemporary influences in head and neck surgery will continue to affect the future of maxillofacial prosthodontics. Advanced digital technologies appeared to be central to driving change. Understanding the evolution of maxillofacial prosthodontics was an important first step in providing context when interpreting the results of a survey of maxillofacial prosthodontists reported as Part II of this work.

Use of Patient-Specific Finite Element Models in Dental Rehabilitation to Investigate Stresses of a Fibula Free Flap for Mandibular Reconstruction.

PURPOSE: This study investigated the effect of implant length, diameter, and surface contact on the stresses developed in a fibular free flap. MATERIALS AND METHODS: Finite element (FE) models for dental implants placed in a patient-specific fibula were created using a patient-specific fibula CT scan and geometry files of commercially available dental implants. The FE models involved nine dental implants of different lengths and diameters: 3.5, 4.3, and 5.0 mm in diameter and 10.0, 11.5, and 13.0 mm in length. Three contact conditions between the implant and the fibular flap were investigated: complete fusion, friction, and smooth contact, representing complete osseointegration, a rough implant-bone interface, and no osseointegration, respectively. Finite element analysis was performed to examine the average von Mises stresses around the local implant-fibula interface within the fibula under a load of 500 N along the long axis of the implant and posterior-anterior and lateral-medial directions. RESULTS: Both the level of osseointegration and implant size had noticeable effects on the mechanical stress inside the fibula. The stress introduced to the fibula gradually decreased as the implant osseointegrated into the bone. An optimal implant size existed where the internal stresses were minimized; this trend was seen when investigating both the implant diameter and length. In this study, an implant with a diameter of 4.3 mm and length of 10 mm produced the lowest mechanical stresses overall. CONCLUSION: Both implant length and diameter were influential; stresses were seen to decrease to a minimum then subsequently increase as either dimension increased. Additionally, stresses in bone introduced by an implant decreased as the degree of interaction between the implant and fibula increased. Complete fusion between the implant and bone yielded the lowest stresses.

Integration of digital technology in the workflow for an osseointegrated implant-retained nasal prosthesis: A clinical report.

This clinical report describes the integration of digital technology into the treatment of a patient with an osseointegrated implant-retained nasal prosthesis. The surgery was planned digitally to determine the optimal implant positions. Implant placement surgical guides were digitally designed and additively manufactured. Prosthetic components, including the nasal form and substructure, were simulated digitally. Based on this simulated prosthetic model, patient-specific abutments were digitally designed and copy-milled. Prototypes for the substructure and prosthesis were 3D printed. Spectrophotometry and computerized color formulation were used to generate the silicone base color of the prosthesis, and characterization was performed by eye. The integration of digital technology allowed for optimized prosthetic retention, predictable esthetic outcomes, and reduced patient appointment time.

Digital design of patient-specific abutments for the retention of implant-retained facial prostheses.

The present report describes the digital design of patient-specific milled abutments for the retention of osseointegrated facial prostheses by using digital technology. Patient imaging including surface scans of the patient's head, scans of the patient's definitive cast, and digitally designed prosthesis prototypes were combined to create a digital simulation of the patient. Using this simulation, patient-specific abutments were digitally designed, printed in 3-dimensions (3D), and finally copy-milled in titanium. This process provided the patient with an optimal abutment design for prosthetic retention, hygiene control, and skin emergence profile.

Functional and quality of life outcomes after partial glossectomy: a multi-institutional longitudinal study of the head and neck research network.

BACKGROUND: While aggressive treatment for oral cancer may optimize survival, decrements in speech and swallowing function and quality of life often result. This exploratory study investigated how patients recover their communicative function, swallowing ability, and quality of life after primary surgery [with or without adjuvant (chemo)radiation therapy] for tongue cancer over the course of the first year post-operation. METHODS: Patients treated for oral cancer at three institutions (University of Alberta Hospital, Mount Sinai Beth Israel Medical Center, and Turku University Hospital) were administered patient-reported outcomes assessing speech [Speech Handicap Index (SHI)], swallowing [(M.D. Anderson Dysphagia Inventory (MDADI)] and quality of life [European Organization for Research and Treatment of Cancer Quality of Life Questionnaire Head and Neck Module (EORTC-H&N35)]. Outcome measures were completed pre-operatively and at 1-, 6-, and 12-months post-operatively. RESULTS: One hundred and seventeen patients undergoing partial glossectomy with reconstruction participated in this study. Results indicated no significant differences in swallowing function (MDADI and EORTC-H&N35 subscales) between baseline and 6 months post-surgery and no significant differences in speech function (SHI subscales) between baseline and 1 year post-surgery. Most quality of life domains (EORTC-H&N35 subscales) returned to baseline levels by 1 year post-operation, while difficulties with dry mouth and sticky saliva persisted. A clear time trend of adjuvant (chemo)radiation therapy negatively affecting dry mouth scores over time was identified in this study, while negative independent effects of chemoradiation on MDADI swallowing, and EORTC-H&N35 swallowing, eating, and opening mouth subscales were found. CONCLUSIONS: Assessment time influenced patient-reported speech, swallowing, and quality of life outcomes, while treatment (by time) effects were found for only swallowing and quality of life outcomes. Results of the present study will help guide clinical care and will be useful for patient counseling on expected short and long-term functional and quality of life outcomes of surgical and adjuvant treatment for oral cavity cancer.

Long-Term Follow-Up of Osseointegrated Orbital Prosthetic Reconstruction.

BACKGROUND: Osseointegrated implants have been used for craniofacial prosthetic reconstruction since 1979. The authors sought to review long-term outcomes of osseointegrated orbital reconstruction at the Institute for Reconstructive Sciences in Medicine (iRSM). METHODS: Twenty-six patients have undergone osseointegrated orbital prosthetic (OOP) reconstruction at iRSM since 1991. A retrospective chart review was performed and patient satisfaction assessed through a questionnaire used in previous osseointegration studies. Multivariate binary logistic regression analysis was performed to assess the relationship between smoking, age, sex, and previous radiation treatment with the occurrence of skin reactions and implant failures. A χ test was used to assess the relationship between implant position within the orbit and development of a skin reaction or implant failure. RESULTS: Patients received an average of 5.8 implants during the course of treatment. Follow-up ranged from 6 months to 24 years (mean = 10.6 years). A statistically significant correlation was found between skin reaction and age (P = 0.022), with younger patients more likely to develop a reaction. No variables in our model were significant for predicting implant failure. Overall, there were 39 failures of 155 osseointegrated implants, for a success rate of 74.8%. There was no relationship between skin reaction and implant failure compared to implant position within the orbit. Survey responses were received from 11 of 19 patients (58% response rate). Ninety-one percent of patients were overall satisfied with their prosthesis. CONCLUSIONS: There are minimal contraindications for consideration of OOP reconstruction. Patients find their prosthesis comfortable, report increased self-confidence, and are happy to have undergone reconstruction.

Implant Utilization and Time to Prosthetic Rehabilitation in Conventional and Advanced Fibular Free Flap Reconstruction of the Maxilla and Mandible.

PURPOSE: Precisely designed jaw reconstruction rehabilitation (JRR) is important to the integrity of the jaw structure and oral functions. Advanced three-dimensional (3D) digital surgical design and simulation (SDS) techniques have the potential to reduce time to reconstructive and dental treatment completion, thereby promoting early functional oral rehabilitation. This study investigated the use of SDS in JRR procedures. MATERIALS AND METHODS: A retrospective chart review was conducted on adult head and neck tumor (HNT) participants who completed JRR treatment with a fibular free flap (FFF) reconstruction. Two treatment approaches, advanced 3D SDS technique (with-SDS) and conventional, nondigitally planned technique (without-SDS), included the use of osseointegrated implants. Data were collected from adult patients treated between January 2000 and March 2014 at the Institute for Reconstructive Sciences in Medicine (iRSM). Participants were excluded if they underwent a bone-containing augmentation to the FFF reconstruction. The without-SDS group underwent a conventional, nonguided FFF reconstruction followed by nonguided implant placement. The with-SDS group underwent a guided FFF reconstruction with guided implant placement during the reconstructive surgery. The outcome measures included implant utilization (ratio of implants placed to connected) and time to prosthetic connection after FFF reconstruction. Mann-Whitney U test was used to analyze the data. RESULTS: The digital SDS technique (with-SDS) group completed prosthetic treatment with a significantly higher utilization of implants as well as a significantly shorter time to prosthetic delivery. CONCLUSION: SDS allows an interdisciplinary treatment team to work together to create a virtual plan that leads to greater efficiency in patient treatment time and utilization of dental implants.

The effect of the angle of acuteness of additive manufactured models and the direction of printing on the dimensional fidelity: clinical implications.

The influence of the acuteness of the model angle and the direction of printing was investigated on different three-dimensional (3D) printers to understand the fidelity of 3D printing. A Polyjet printer and two fused deposition modeling printers were used in the present study. Computer-aided design (CAD) models were designed in the form of a triangular prism with a height of 15 mm and with varying angles of 60°, 45°, 30°, 20°, 10°, and 5°. From the CAD designs, additive manufacturing (AM) models were printed in three different directions by each of the three printers. To investigate the global fidelity of the 3D printers, the height and surface outlines of the AM model cross sections were measured. The fidelity of the AM models with increasingly acute angles was not accurately reproduced when 3D printed, and the surface outlines of the AM model cross sections were different in each direction of printing for each device. Printing technology and printing direction need to be considered if accurate reproduction of acute angles in fine AM structures in medical models is a necessity.

Anatomical examination of the fibula: digital imaging study for osseointegrated implant installation.

BACKGROUND: Free vascularized fibular flaps are commonly used in jaw reconstruction. CT scan images of the fibula are used in digital planning of jaw reconstruction. In order to fully describe the anatomy of the fibula, an imaging study of the fibula was undertaken. The purpose of the present study was to examine the anatomical structure of the fibula using patient CT images. METHODS: The CT scan images of fibulae of 20 patients were used for the study. The results of the analysis showed that, of the widths, the anterior border of the fibula to the posterior surface was the largest dimension. The shape type analysis showed that the triangular type was most prominent near the head of the fibula, and the irregular type was most prominent towards the lateral malleolus. RESULTS: The results of height and width related to the long axis of implant installation showed that the width of the central section was the largest. With respect to the length of available bone volume, the length near the lateral malleolus was larger than that near the head of the fibula. The results showed that there were significant differences in size between male and female fibulae. CONCLUSION: The present study provides a CT scan based analysis of the anatomy of the fibula. Important information for the optimal site of installation of osseointegrated implants in fibular free flap reconstructions is also provided.

Functional outcomes for clinical evaluation of implant restorations.

The functional outcomes related to treating patients afflicted with tooth loss are an important hallmark in substantiating prosthodontic intervention. The Oral Rehabilitation Outcomes Network (ORONet) conducted two international workshops to develop a core set of outcome measures, including a functional domain. The process followed the general format used in the Outcome Measures in Rheumatology (OMERACT) workshops to develop consensus for clinical outcome measures in arthritis research, which included: developing a comprehensive list of potential outcomes in the literature; submitting them to a filter for validity, clinical discrimination, and feasibility; and ranking those measures meeting all the filter criteria for relative value. The search was conducted to include functional assessments of speech, swallowing, mastication, nutrition, sensation, and motor function as they relate to dental implant therapies. This literature review surveyed 173 papers that produced some result of these descriptors in the functional domain. Of these, 67 papers reported on functional assessments and further defined objective and subjective outcomes. Many of these results were patient-perceived improvements in function, while others were objective assessments based on established methodologies and instruments. Objective evaluations of masticatory function and speech may meet criteria for validity and discriminability for selected interventions, but are generally not feasible for routine use in clinical care settings. The current recommendation is to employ a well-validated survey instrument that covers mastication and speech, such as the Oral Health Impact Profile (OHIP-14, short form), recognizing that patient perceptions of function may differ from objective ability.

Psychologic outcomes in implant prosthodontics.

Consensus regarding outcomes of the treatment of tooth loss, especially the psychologic outcomes, is needed to guide discovery of best practices and enable a better understanding of patient management for this chronic condition. This paper presents the findings of the ORONet Psychological Working Group for prosthodontics and aims to identify psychologic outcomes with properties deemed critical to meet clinical trial and clinical practice needs for the future. References obtained using a PubMed/Medline search were reviewed for clinical outcomes measures of interest. Clinical outcomes measures were judged relative to the criteria of truth, discrimination, and feasibility. Of the psychologic outcome measures identified in this systematic review, only the OHIP-14 was thought to be suitable for use in general practice and multi-institutional outcome registries and clinical trials. Development of clinically useful psychologic outcomes for future use could benefit from developmental methods and tools outlined in the patient-related outcomes field of clinical care.

Economic outcomes in prosthodontics.

PURPOSE: A systematic literature review was conducted to identify the types of economic measures currently used in implant prosthodontics and determine the degree to which cost of care is considered in the context of any positive outcome of the care provided. MATERIALS AND METHODS: A literature search was conducted using the following set of terms plus some additional hand searching: "dental implants" (Mesh) AND ("cost") OR "maintenance" OR "healthcare policy" OR "access to care" OR "third party" OR "economic") AND (("1995/01/01"[PDat]:'2009/12/31"[PDat]) AND (Humans[Mesh]) AND (English[lang])). RESULTS: After a review of the 466 titles and abstracts identified by the search, 18 articles were accepted for further consideration, as some attempt at economic outcome measures was made. An additional four articles were identified by hand searching. The 22 accepted articles were grouped into four basic categories: (1) measure of costs of treatment (direct, indirect, and maintenance costs), (2) cost-effectiveness mathematical modeling applied to simulate the lifetime paths and cost of treatment, (3) cost-effectiveness analysis/cost minimization, and (4) willingness-to-pay, willingness-to-accept. Attempts at determining the costs of treatment varied widely. When the OMERACT filters were applied to the various measures it was felt that discrimination and/or feasibility was a problem for most of the current economic outcome measures. CONCLUSIONS: Measures of cost-benefit, cost-effectiveness, and cost-utility are currently the gold standard; however, feasibility of such analyses is an issue. Collaboration with health economists to guide future research is highly recommended.

Oral Rehabilitation Outcomes Network-ORONet.

The published literature describing clinical evidence used in treatment decisionmaking for the management of tooth loss continues to be characterized by a lack of consistent outcome measures reflecting not only clinical performance but also a range of patient concerns. Recognizing this problem, an international group of clinicians, educators, and scientists with a focus on prosthodontics formed the Oral Rehabilitation Outcomes Network (ORONet) to promote strategies for improving health based on comprehensive, patient-centered evaluations of comparative effectiveness of therapies for oral rehabilitation. An initial goal of ORONet is to identify outcome measures for prosthodontic therapies that represent multiple domains with patient relevance, are amenable to utilization in both institutional and practice-based environments, and have established validity. Following a model used in rheumatology, the group assessed the prosthodontic literature, with an emphasis on implantbased therapies, for outcomes related to longevity and functional, psychologic, and economic domains. These systematic reviews highlight a need for further development of standardized outcomes that can be integrated across clinical and research environments.

Clinical outcomes measures for assessment of longevity in the dental implant literature: ORONet approach.

The Oral Rehabilitation Outcomes Network (ORONet) Longevity Working Group undertook a search of the literature from 1995 to 2009 on randomized controlled trials related to longevity of osseointegrated implants. Outcomes measures used in these studies were identified and subjected to the OMERACT component criteria of truth, validity, and feasibility. Through this process, it was a challenge to identify clinical outcomes measures that fully met the criteria. An attenuated version of the component criteria was applied, and clinical measures were identified for implant outcomes, prosthetic outcomes, and indices. A recommendation on standardized reporting periods was also presented for future consideration. The endpoint of the evaluation process is to develop consensus on clinical outcomes measures that can be applied across broad populations for osseointegrated implant care. The present ORONet initiative represents a beginning toward continual improvement and consensus development for clinical outcomes measures for osseointegrated implants.

Pilot study: evaluation of the use of the convergent interview technique in understanding the perception of surgical design and simulation.

BACKGROUND: It is important to understand the perceived value of surgical design and simulation (SDS) amongst surgeons, as this will influence its implementation in clinical settings. The purpose of the present study was to examine the application of the convergent interview technique in the field of surgical design and simulation and evaluate whether the technique would uncover new perceptions of virtual surgical planning (VSP) and medical models not discovered by other qualitative case-based techniques. METHODS: Five surgeons were asked to participate in the study. Each participant was interviewed following the convergent interview technique. After each interview, the interviewer interpreted the information by seeking agreements and disagreements among the interviewees in order to understand the key concepts in the field of SDS. RESULTS: Fifteen important issues were extracted from the convergent interviews. CONCLUSION: In general, the convergent interview was an effective technique in collecting information about the perception of clinicians. The study identified three areas where the technique could be improved upon for future studies in the SDS field.

Exploratory benchtop study evaluating the use of surgical design and simulation in fibula free flap mandibular reconstruction.

BACKGROUND: Surgical design and simulation (SDS) is a useful tool to help surgeons visualize the anatomy of the patient and perform operative maneuvers on the computer before implementation in the operating room. While these technologies have many advantages, further evidence of their potential to improve outcomes is required. The present benchtop study was intended to identify if there is a difference in surgical outcome between free-hand surgery completed without virtual surgical planning (VSP) software and preoperatively planned surgery completed with the use of VSP software. METHODS: Five surgeons participated in the study. In Session A, participants were asked to do a free-hand reconstruction of a 3d printed mandible with a defect using a 3d printed fibula. Four weeks later, in Session B, the participants were asked to do the same reconstruction, but in this case using a preoperatively digitally designed surgical plan. Digital registration computer software, hard tissue measures and duration of the task were used to compare the outcome of the benchtop reconstructions. RESULTS: The study revealed that: (1) superimposed images produced in a computer aided design (CAD) software were effective in comparing pre and post-surgical outcomes, (2) there was a difference, based on hard tissue measures, in surgical outcome between the two scenarios and (3) there was no difference in the time it took to complete the sessions. CONCLUSION: The study revealed that the participants were more consistent in the preoperatively digitally planned surgery than they were in the free hand surgery.