[Construction and application of virtual patients in prosthodontics].

In recent years, with the rapid development of digital technology, the application of oral virtual patients in prosthodontics, orthodontics, oral and maxillofacial surgery, and other disciplines has gradually increased. Although the focus on oral virtual patients varies in different disciplines, the application of oral virtual patients in assisting the prediction of treatment effects and the formulation of treatment plans will have good prospects. The construction accuracy and presentation effects of oral virtual patients can be influenced by the source of three-dimensional (3D) image, and methods of registration. Based on the studies and clinical experiences of our team, researches of other teams, the source of 3D images, the construction methods, and the clinical applications of virtual patients in prosthodontics will be presented, so as to provide a reference for normalized application and development of oral virtual patients and to offer a future development direction of oral virtual patients.

Preparation and application of chitosan biomaterials in dentistry.

Chitosan is a biodegradable and biocompatible natural polysaccharide that has a wide range of applications in the field of dentistry due to its functional versatility and ease of access. Recent studies find that chitosan and its derivatives can be embedded in materials for dental adhesives, barrier membranes, bone replacement, tissue regeneration, and antimicrobial agent to better manage oral diseases. In this paper, we provide a comprehensive overview on the preparation, applications, and major breakthroughs of chitosan biomaterials. Furthermore, incorporation of chitosan additives for the modification and improvement of dental materials has been discussed in depth to promote more advanced chitosan-related research in the future.

Flexural strength of polyether ether ketone high-performance polyether in comparison with base metal alloy and zirconia ceramic / Resistencia a la flexión del poliéter éter cetona poliéter de alto rendimiento en comparación con la aleación de metal base y la cerámica de circonio

Optimal flexural strength is a critical prerequisite for prosthetic frameworks. This study aimed to assess the flexural strength of polyether ether ketone (PEEK) polymer compared to a base metal alloy and high-strength Zirconia ceramic commonly used in prosthodontic treatments. Materials and Methods: In this in vitro, experimental study, 10 bar-shaped samples measuring 18×5×2mm were fabricated of each the PEEK polymer, nickel-chromium base metal alloy and zirconia ceramic. Half of the samples in each group were subjected to 5000 thermal cycles between 5°C - 55°C with 20 seconds of dwell time and 20 seconds of transfer time to simulate oral conditions. All samples then underwent three-point bending test. Two-way ANOVA followed by Tukey's test were applied to compare the mean flexural strength of the groups with and without thermocycling at 0.05 level of significance. Results: The flexural strength of base metal alloy, Zirconia and PEEK was 1387.70±45.50 MPa, 895.13±13.99 MPa and 192.10±5.37 MPa, respectively. The difference was significant among the groups (p<0.001). Thermocycling had no significant effect on the flexural strength of samples in any group (p=0.306). Conclusion: PEEK high-performance polymer had a lower flexural strength than base metal alloy and Zirconia ceramic, and its flexural strength was not affected by thermocycling. PEEK seems to be able to resist masticatory forces in the oral cavity pending further in vitro and clinical studies.

La resistencia a la flexión óptima es un requisito previo crítico para los marcos protésicos. Este estudio tuvo como objetivo evaluar la resistencia a la flexión del polímero de poliéter éter cetona (PEEK) en comparación con una aleación de metal base y cerámica de Zirconia de alta resistencia comúnmente utilizada en tratamientos de prostodoncia. Materiales and Métodos: En este estudio experimentalin vitro, se fabricaron 10 muestras en forma de barra de 18 × 5 × 2mm de cada polímero PEEK, aleación de metal base de níquel-cromo y cerámica de circonio. La mitad de las muestras en cada grupo fueron sometidas a 5000 ciclos térmicos entre 5°C - 55°C con 20 segundos de tiempo de permanencia y 20 segundos de tiempo de transferencia para simular condiciones orales. Todas las muestras se sometieron a una prueba de flexión de tres puntos. Se aplicó ANOVA bidireccional seguido de la prueba de Tukey para comparar la resistencia a la flexión media de los grupos con y sin termociclado a un nivel de significancia de 0.05. Resultados: La resistencia a la flexión de la aleación de metal base, Zirconia y PEEK fue de 1387,70 ± 45,50 MPa; 895,13 ± 13,99 MPa y 192.10 ± 5,37 MPa, respectivamente. La diferencia fue significativa entre los grupos (p<0,001). El termociclado no tuvo un efecto significativo sobre la resistencia a la flexión de las muestras en ningún grupo (p=0,306).Conclusión:El polímero de alto rendimiento PEEK tiene una resistencia a la flexión más baja que la aleación de metal base y la cerámica de circonio, y su resistencia a la flexión no se vio afectada por el termociclado. PEEK parece ser capaz de resistir las fuerzas masticatorias en la cavidad oral, con la necesidad de más estudios in vitroy clínicos.

Reconstructive and prosthodontic outcomes after multiple palatomaxillary reconstructions.

OBJECTIVE: A subset of patients who undergo major palatomaxillary reconstruction do not initially achieve their intended oncologic and/or reconstructive goals and require additional surgery. We aim to detail the unique management considerations in this patient population. METHODS: We performed a retrospective review of patients who underwent palatomaxillary reconstruction by the senior author (m.l.u.) between 1998 and 2016. RESULTS: Twenty-one patients required multiple reconstructions. The median time to second reconstruction was 17 months. The most common reason for a second reconstruction was for recurrent disease (10 of 21), followed by functional/aesthetic reasons (7 of 21) and osteoradionecrosis (4 of 21). Four patients went on to have a third reconstruction, and two underwent a fourth. A total of 27 reconstructions were performed, consisting of 20 soft tissue free flaps, four vascularized bone free flaps, and three locoregional flaps. CONCLUSION: This patient cohort represents unique oncologic and reconstructive challenges. With long-term follow-up, multiple reconstructions may be required to optimize oncologic and functional/aesthetic outcomes. This is the first series of its kind that details the reasons for, as well as the outcomes of, patients who required multiple reconstructive procedures following initial palatomaxillary reconstruction. LEVEL OF EVIDENCE: 2B Laryngoscope, 130:2349-2353, 2020.

Radiosurgery in dentistry: a review.

The aim of the present study was to analyse the clinical potential of radiosurgery applied to modern dentistry through a revision of the indexed literature. Radiosurgery represents a recent form of electrosurgery working at a frequency of 3.0-4.0 MHz. The depth of penetration of the waves is inversely proportional to the frequency. Radiowaves working at high frequency express a lower penetration with a consequent lower tissue alteration. The authors analyzed the literature in order to give to the scientific community an overview of the possible applications of radiosurgery in the clinical dental practice and their effectiveness. Radiosurgery can be used in prosthodontics, in periodontal and implant surgery, in the treatment of trigeminal neuralgia, in the treatment of obstructive sleep apnea syndromes (OSAS) and in endodontics. Our analysis shows that although there are few articles in indixed literature on the applications of radiosurgery in dentistry, thanks to the benefits that derive from it, radiosurgery will spread more in the daily clinical practice of the dentists.

The smiling scan technique: Facially driven guided surgery and prosthetics.

PURPOSE: To introduce a proof of concept technique and new integrated workflow to optimize the functional and esthetic outcome of the implant-supported restorations by means of a 3-dimensional (3D) facially-driven, digital assisted treatment plan. METHODS: The Smiling Scan technique permits the creation of a virtual dental patient (VDP) showing a broad smile under static conditions. The patient is exposed to a cone beam computed tomography scan (CBCT), displaying a broad smile for the duration of the examination. Intraoral optical surface scanning (IOS) of the dental and soft tissue anatomy or extraoral optical surface scanning (EOS) of the study casts are achieved. The superimposition of the digital imaging and communications in medicine (DICOM) files with standard tessellation language (STL) files is performed using the virtual planning software program permitting the creation of a VDP. CONCLUSIONS: The smiling scan is an effective, easy to use, and low-cost technique to develop a more comprehensive and simplified facially driven computer-assisted treatment plan, allowing a prosthetically driven implant placement and the delivery of an immediate computer aided design (CAD) computer aided manufacturing (CAM) temporary fixed dental prostheses (CAD/CAM technology).

Prosthodontic management of maxillofacial cases: a case series.

Maxillofacial prosthetics is an important and recognized sub-discipline of prosthodontics that forms a key component of postgraduate training programmes. General dentists have a role to play in the management of maxillofacial defect patients even though treatment usually requires a multidisciplinary approach in an institutional environment. Maxillofacial prosthetic cases frequently present with complex histories but simple patient goals. The conservatively managed implant-retained auricular prosthesis, speech aid prosthesis and orbital prosthesis cases described in this report were completed in a postgraduate clinical residency program and highlight the intrinsic complexities, challenges and ultimately satisfaction related to cases of this nature.

Prosthodontic rehabilitation with monolithic, multichromatic, CAD-CAM complete overdentures in an adolescent patient with ectodermal dysplasia: A clinical report.

Ectodermal dysplasia is a rare, hereditary, congenital disease that affects the normal development of certain tissues and structures of ectodermal origin. The disease is manifested to different degrees of severity and may involve the nose, eyes, hair, nails, sweat glands, and enamel. This report describes a 14-year-old boy with ectodermal dysplasia, rehabilitated with monolithic, multichromatic maxillary and mandibular computer-aided design and computer-aided manufacturing (CAD-CAM) acrylic resin complete overdentures.

Prefabricated Laser Sintered Composite Veneers and Occlusal Vertical Dimensions: Case Reports.

AIM: To highlight the concept of prefabricated veneers and occlusal vertical dimension (OVD) and series of case report using edelweiss prefabricated veneer system. BACKGROUND: Edelweiss prefabricated veneer system presents a concept of biofunctional esthetics using laser sintered composite resins. The system's biofunctionality and versatile area of application combined with its time and cost saving procedure make the Edelweiss veneer and occlusion system a sound investment for the future. CASE DESCRIPTION: A series of case reports treated using prefabricated laser sintered composite veneer system has been presented. CONCLUSION: Prefabricated veneer is a milestone in operative dentistry, as it contributes tremendously to direct composite application, helping a larger number of our patients to receive esthetic restorations that are more conservative and affordable. CLINICAL SIGNIFICANCE: The prefabricated composite veneering technique provides a minimally invasive, chair-side technique for esthetic and full mouth rehabilitation.

Clinical factors in prosthodontic treatment of children with genetic defects.

BACKGROUND: Prosthodontic treatment of children with genetic disorders is an area that is rarely examined in the current specialist literature. Few prosthodontists will undertake treatment of such patients, who will more often be referred to an orthodontic specialist. After examining the 4 cases of children with genetic disorders described in this paper, it can be concluded that when a prosthodontist includes a few additional procedures in the treatment process, he or she can successfully help such patients. OBJECTIVES: The aim of this paper is to indicate the clinical difficulties faced by prosthodontists who undertake prosthodontic rehabilitation of children with genetic disorders. MATERIAL AND METHODS: The paper is based on data collected during the prosthodontic treatment of 4 children, aged 5-12 years with genetic defects, and analysis of the body of work concerning these defects and their treatment. RESULTS: Presentation of guidelines for the prosthodontic treatment process and creation of dentures for treated children based on extended procedures. CONCLUSIONS: A prosthodontist is a crucial person in a team of specialists treating disorders within the face among children with a genetic predisposition. A basic knowledge of orthodontics and psychology facilitates the treatment. Prosthetic restoration in the treatment group does not always require complicated operations. Individualization of the tools for downloading orthodontic impressions, designing denture elements and an increased number of checkups are the additional procedures. For the clinician, the emotional aspect of the treatment is the main impediment. Maintaining a good relationship with a patient and his or her caregivers requires interpersonal skills.

Swinging Replantation: A Possible Protocol for the Management of Inverted Impacted Upper Central Incisor Tooth.

INTRODUCTION: Inverted tooth impaction is a rare occurrence. Third molar impaction is the most extensively studied, and only eight cases of inverted third molars have been reported in a literature search of 40 years from 1973 to 2013. In a study, 43.4% of the premaxillary supernumeraries were inverted and 21.1% were transversely oriented, while occasional inverted central incisors have been mentioned in the literature. Severe dilaceration makes the management of this case a big challenge. The case of an 8-year-old boy with an inverted, rotated, and impacted upper left central incisor obstructed by an odontome is presented here. Under local anesthesia, the odontome was excised; the inverted tooth was swung and repositioned. The patient experienced uneventful healing, and with 30 months follow-up, progressive tooth eruption has been observed. Vitality test is positive, while radiologically there was no sign of resorption. Swinging replantation is a protocol that has been used for the management of an inverted, rotated, and impacted central incisor. Open root apex is an important factor in the selection of the method. The minimal periodontal damage prevents inflammatory and replacement resorption. With some clear advantages over options like orthodontic and prosthetic replacement, it could be a method to be considered in the management of severely dilacerated central incisors. The clinical significance is that even though management of a severely malpositioned tooth has always been a big challenge in dental practice, requiring extraction and prosthodontic replacement, swinging replantation provides a possible protocol of tooth retention, i.e., less expensive and associated with fewer hospital visits.

Prosthodontic considerations for managing the older adult patient.

As the baby boom generation ages, it is projected that by 2050 the number of Americans older than 65 years of age will increase to a staggering 88 million. Those Americans 85 years and older will soon represent the fastest growing segment of the population, predicted to surge to 20 million by 2060. Management of chronic disease processes affecting older Americans will consume 86% of the nation's healthcare expenditures. Dentists and specialists alike must understand these disease processes and become active members of the healthcare team. Oral healthcare providers should become astute at developing treatment plan modifications that take into account the various medical conditions affecting the older adult population and provide restorative care that may simplify oral maintenance procedures as this population of patients continues to age.

[Prosthodontic care of orofacial clefts in adulthood: About a clinical case]. / Prise en charge prothétique des fentes oro-faciales à l'âge adulte: A propos d'un cas Clinique.

This paper relates, through a clinical case, the different steps of the prosthodontic rehabilitation of a palate-pharyngeal cleft, sequelae to surgery, by performing a Suersen's Velar obturator since the soft Palate is divided but toned. A functional reeducation in conjunction with a prosthodontic care improves the quality of life's patients and help for their resocialization. This therapeutic is non-invasive, quick, efficient and evolutive method.

[COMBINED ACRYLIC-POLYPROPYLEN REMOVABLE PROSTHESES FOR PROSTHODONTIC TREATMENT].

The article deals with the development of methods to prevent complications with prosthetic dentures patients with psychiatric status. The authors developed a method of manufacturing the denture using modern thermoplastic materials, the use of which in practice does not cause prosthetic stomatitis in patients with psychiatric status. The proposed methodology has been tested clinically. Based on Schiller- Pisarev and study fixation of prostheses has been shown the advantage of the prosthesis used for prosthetics partial dentition defects that can not be fixed prosthetics in this category of patients.

Interdisciplinary treatment of an adult with bilateral cleft lip and palate with missing premaxilla: The prosthodontic perspective.

Conventional orthognathic surgery and orthodontic techniques occasionally fail to completely correct the occlusal relationship and esthetic deficits of patients with cleft lip and palate and severe midface deficiency. Prosthodontic rehabilitation is often required to establish adequate occlusion and provide a more proportional facial appearance. This clinical report describes the interdisciplinary management of an adult with complete bilateral cleft lip and palate who was treated with distraction osteogenesis using a rigid external distraction device for maxillary advancement and his prosthodontic rehabilitation with a dual path removable partial overdenture to develop definitive facial and dental esthetic form.

Prosthodontic Considerations in Post-cancer Reconstructions.

The restoration of function after oncologic surgery of the oral cavity constitutes one of the major challenges facing head and neck oncology. Within the general objective of securing esthetic as well as functional reconstructions, dental rehabilitation is crucial for achieving a good outcome. Adequate dental rehabilitation allows the patient to chew food and considerably improves speech and swallowing. These reconstructions will be driven biologically or prosthetically following surgical design and outcome.