Full-arch implant-supported monolithic zirconia fixed dental prostheses: An updated systematic review.

PURPOSE: To update an existing systematic review assessing the clinical performance of full-arch implant-supported monolithic zirconia fixed dental prostheses. MATERIALS AND METHODS: The review was conducted according to the guidelines outlined in the Preferred Reporting Items of Systematic Reviews and Meta-analyses (PRISMA) statement. An electronic search was conducted using the PubMed, Science Direct and Cochrane Library databases to identify clinical studies on full-arch implant-supported monolithic and minimally layered zirconia fixed dental prostheses. Human studies with a mean follow-up of at least 1 year and published in an English-language peer-reviewed journal up to April 2020 were included. Two independent examiners conducted the search and the review process. RESULTS: The search generated 2110 articles. Thirty-three qualifying studies were retrieved for full-text evaluation and a total of 17 studies were included on the basis of preestablished criteria. All 17 studies reported satisfactory clinical and aesthetic outcomes. The technical complication rate related to this type of prosthesis is still minimal and survival rates are high. CONCLUSIONS: Full-arch dental implant restoration with monolithic zirconia is associated with high short-term success. Long-term data from studies with a strong level of evidence are still lacking.

Methodological Quality of Systematic Reviews Relating to Performance of All-Ceramic Implant Abutments, Frameworks, and Restorations.

PURPOSE: To assess the methodological quality of published systematic reviews relating to all ceramic implant frameworks, abutments and restorations. MATERIALS AND METHODS: Published systematic reviews relating to all ceramic implant restorations for single tooth and multiple teeth replacements were retrieved to assess their methodological qualities. Sixteen systematic reviews were included for methodological quality assessment by two independent assessors using AMSTAR-2 critical appraisal tool. Inter-rater agreement was assessed using the weighted Cohen's Kappa statistic. RESULTS: Most systematic reviews included randomized clinical trials and nonrandomized studies of intervention. The majority of included systematic reviews (15 out of 16) scored critically low on quality with more than one critical flaw when assessed using the AMSTAR-2 tool. Most systematic reviews assessed lacked analysis of the effects of the risk of bias and heterogeneity of the included studies. The inter-rater agreement of the independent assessors was substantial (0.63). CONCLUSIONS: Confidence in the evidence presented in these systematic reviews was undermined by their tendency to overlook the effect of risk of bias and heterogeneity in evidence synthesis.

Dental students' experience and perceived confidence level in different restorative procedures.

PURPOSE: Graduating confident students who are able to flourish and develop in their future careers is an importance outcome of the dental education. This study aims to evaluate self-perceived level of confidence of fifth-year dental students in different restorative-related tasks and the relationship between their clinical training and its corresponding confidence. METHODS: Fifth-year graduate dental students (n = 202) were asked to fill a questionnaire that rated their level of confidence in different clinical restorative dentistry tasks. Additionally, they were asked about the number of times they performed tasks prior to attempting the equivalent competency and in which sub-specialty they felt the most confident. RESULTS: Completed responses were received from 120 students giving a response rate of 59%. Students felt the most prepared and confident in direct restorations and simple endodontic treatment, and they seemed less confident in indirect restorations and complex endodontic treatment. Regarding the steps of indirect restorations, students expressed least confidence in crown preparation compared to impression making and try-in procedures (P < .05). Students rated their confidence highest in operative dentistry, followed by endodontics and lastly fixed prosthodontics. CONCLUSION: The results highlight the areas in which students exhibit the least confidence. Enhancement of student clinical skills and directed exposure is necessary to raise the level of perceived confidence which will reflect positively on their current and future professional performance.

Dentists' knowledge, attitudes, and professional behavior toward the COVID-19 pandemic: A multisite survey of dentists' perspectives.

BACKGROUND: COVID-19 continues to affect the dental community worldwide. The authors conducted a cross-sectional electronic study using a multisite survey to examine dentists' knowledge, attitudes, and professional behavior toward COVID-19 and the affect on their livelihood. METHODS: A questionnaire was circulated via e-mail and social media platforms to dentists in North America, Europe, Eastern Mediterranean, and Western Pacific regions. It covered demographic characteristics and questions about the COVID-19 outbreak related to dentists' levels of comfort for preventive and safety measures, provision of treatment, affect on work, and financial implications. Responses were tabulated and analyzed by means of χ2 or Fisher exact test. Mann-Whitney and Kruskal-Wallis tests were used to compare means. P < .05 was considered significant. RESULTS: A total of 1,251 dentists responded. General dentists represented 63.9% of the respondents and 62.5% worked in private practice. The global score for level of comfort with the preventive measures and provisions of treatment during the COVID-19 pandemic was low (14 of 30), and differences between regions were significant (P < .01); dentists working in private practice and general dental practitioners were less comfortable (P < .01). CONCLUSIONS AND PRACTICAL IMPLICATIONS: The respondents reported a lack of preparedness to confront a highly infectious respiratory disease. A new level of protective armamentarium in the dental operatory and updated operational guidance and policies are required, necessitating educators and regulators to ensure the delivery of knowledge and skills to oral health care providers. Dentists need to address the sustainability of their practices and have a robust business plan.

Dental Student Perspectives of a Comprehensive-Based Teaching Methodology: A Confidence, Effectiveness, and Challenge Report.

Background/Objectives. The holistic methodology in education has been widely appreciated and implicated in dental schools in the last decade. Our department of conservative dentistry decided to reform the educational model of teaching from a traditional requirement-based model to a hybrid model incorporating comprehensive care treatment. The aim of our study was to assess students' confidence and perspectives regarding the benefits of a comprehensive model of teaching. Materials and Methods. A questionnaire was distributed at the end of the academic year 2018-2019 and designed to investigate students' opinions on the benefits of the new model of teaching, as well as difficulties encountered and possible shortcomings. In addition, self-perceived confidence level was assessed for the purpose of comparing confidence during supervised tasks versus confidence during comprehensive patient care. Results. Complete responses were gathered from 127 students out of 202, giving a response rate of 63%. The majority of students believed that the comprehensive model of teaching allowed them to better address patients' needs, gave higher satisfaction, positively influenced self-confidence, permitted greater exposure to clinical techniques, and enhanced reasoning and analytical skills. However, their confidence was still lower in comprehensive patient management when compared to supervised tasks. Conclusion. Our students showed an appreciation of the comprehensive care model. Self-learning and didactic skills were enhanced. It would, therefore, be beneficial to adapt this methodology to earlier years and other disciplines to enhance the effectiveness of education and achievement of learning outcomes.

Esthetic outcome of immediately placed and nonfunctionally loaded implants in the anterior maxilla utilizing a definitive abutment: A pilot clinical trial.

BACKGROUND: Immediate dental implants placement and loading utilizing definitive abutments might save time and cost when an esthetic final result is anticipated. The objective of this prospective clinical trial was to evaluate the esthetic outcome of immediate implantation and immediate nonfunctional loading utilizing definitive abutments, with and without bony substitutes filling the peri-implant gap. MATERIALS AND METHODS: In this clinical trial study a total of 11 implants were placed utilizing a flapless immediate post extraction approach in the maxilla (second premolar to second premolar). Atraumatic extraction was performed and implants were immediately placed. The gap was either left without grafting or filled with particulate bone material. Immediate nonfunctional loading was performed utilizing a definitive abutment. The pink esthetic scores (PESs) were assessed preoperatively, at 1- and 2-year follow-up periods. Dental casts were obtained at respective time intervals; scanned, registered, and closest point distances were measured. For all statistical tests, value of P = 0.05 was set as a statistical significance level. RESULTS: The mean of PES at baseline was 9.4 ± 1.69, at 1 year was 9.5 ± 2.07, at 2 years was 10.2 ± 2.75, for the graft group 10.3 ± 2.8, and for nongrafting group was 10.2 ± 2.59. There were no statistically significant differences in PESs at baseline when compared to 1- and 2-year intervals, and for grafting group versus nongrafting group (P = 0.24). Distances between the two time points for all cases were <1 mm in all reference planes. CONCLUSION: Immediate placement and nonfunctional loading utilizing a definitive abutment appear to result in a stable result as far as esthetic outcome and alveolar process sufficiency are concerned.

Dentists' Attitudes in Jordan towards the Shortened Dental Arch Concept: A Cross-Sectional Study.

AIMS: To assess the awareness, knowledge, attitudes, and application of the shortened dental arch (SDA) concept by dentists in Jordan. MATERIALS AND METHODS: In this cross-sectional survey, a questionnaire was disseminated to a random sample of 150 dentists working in private practices, university hospitals, or governmental institutes. The chi-square (X 2 ) test was used to examine associations. RESULTS: One hundred and six dentists responded (70.7% response rate). Fifty-five were females. 82.1% were aware of the SDA concept. The fewer the years of experience, the more likely the dentists were aware of the SDA concept (X 2 , P=0.024) and the more likely they learned about it through undergraduate education (X 2 , P < 0.001). In a hypothetical clinical situation of a patient >50 years of age with missing molar teeth, 45.3% agreed that the molars should be replaced, while 54.7% did not agree. Improving mastication was the main reason for agreeing (81.6%), while having reduced functional benefit was the main reason for disagreeing (64.9%). The treatment modality most commonly recommended was implants fixed partial dentures (84.9%). Of those aware of SDA, 67.8% agreed it could have a useful place in treatment planning within Jordan. Cost reduction for patients was the main reason for this answer, as reported by 51% of those who agreed. 26.4% did not apply SDA for any of their patients, while 50.6% applied it for <10% of their patients. CONCLUSION: The majority of the dentists was aware of the SDA concept and had a positive attitude towards it; however, few of them applied it in their practice.

A multi-center retrospective assessment of monolithic zirconia restorations on posterior teeth and implants / Una evaluación retrospectiva multicéntrica de restauraciones monolíticas de circonio en dientes posteriores e implantes

Objective: the purpose of this multicenter retrospective study was to report on survival, success, and complication rates in monolithic zirconia restorations on teeth and implants. Materials and Methods: data on 671 monolithic zirconia restorations was collected by five prosthodontists from three different specialty practice centers, including a dental school and two private practice centers. Restorations included single crowns and multiple-unit fixed dental prostheses on teeth and implants in the posterior area (premolar and molars). Follow-up time was up to 62 months. Results: mean follow-up time was 28.1±12.9 months. A total of 671 units, 534 single crowns, and 137 multi-unit restorations. Cumulative survival and success rates at 5 years were 97.4%, and 93.8% respectively. Complications presented in 11 restorations out of 671 and included: decementation, abutment screw loosening, restoration crack, restoration fracture, and tooth fracture. No significant differences were observed between tooth-supported and implant-supported restoration (p=0.42), single crowns and multiple-unit restorations (p=0.07), bruxers and non-bruxers (p=0.57). Patients with group function occlusal scheme had significantly less survival rates (p=0.001). Conclusion: the use of monolithic zirconia for restorations on the posterior teeth and implants seems to be promising as it provides a durable solution with a low rate of complications.

Objetivo: el propósito de este estudio retrospectivo multicéntrico fue informar sobre las tasas de supervivencia, éxito y complicaciones en restauraciones monolíticas de circonio en dientes e implantes. Materiales y Métodos: cinco prostodoncistas recolectaron datos de 671 restauraciones monolíticas de zirconia de tres centros de práctica especializados: una escuela de odontología y dos centros de práctica privados. Las restauraciones incluyeron coronas individuales y prótesis dentales fijas de unidades múltiples en dientes e implantes en el área posterior (premolares y molares). El tiempo de seguimiento fue de hasta 62 meses. Resultados: el tiempo medio de seguimiento fue de 28,1±12,9 meses. Un total de 671 unidades, 534 coronas individuales y 137 restauraciones de unidades múltiples. La supervivencia acumulada y las tasas de éxito a los 5 años fueron del 97,4% y del 93,8%, respectivamente. Las complicaciones se presentaron en 11 restauraciones de 671 e incluyeron: fracaso del cementado, aflojamiento del tornillo del pilar, grieta en la restauración, fractura de restauración y fractura de dientes. No se observaron diferencias significativas entre la restauración con soporte dental y con implante (p=0,42), coronas individuales y restauraciones de unidades múltiples (p=0,07), pacientes con bruxismo y sin bruxismo (p=0,57). Los pacientes con esquema oclusal de función grupal tuvieron tasas de supervivencia significativamente menores (p= 0,0 01). Conclusión: el uso de zirconia monolítica para restauraciones en los dientes posteriores y en implantes parece ser prometedor, ya que proporciona una solución duradera con una baja tasa de complicaciones.

Assessment of Bone Dimensions in the Anterior Maxilla: A Cone Beam Computed Tomography Study.

PURPOSE: To evaluate labial and palatal bone thickness at the maxillary anterior teeth as well as distance from cemento-enamel junction (CEJ) to bone crest using cone beam computed tomography (CBCT). MATERIALS AND METHODS: Measurements were obtained for maxillary anterior teeth of 120 subject CBCT volumes including thickness of labial and palatal plates of bone (coronal, middle, and apical thirds), and distance between CEJ and alveolar bone crest mid-labially, mesially, and distally. RESULTS: The mean value of bone thickness at coronal, middle, and apical thirds of the labial side for central incisor roots were respectively: 0.73, 0.69, 0.60 (mm), for lateral incisors: 0.70, 0.61, 0.49 (mm), and for canines: 0.74, 0.53, 040 (mm). The thickness of palatal bone was significantly larger. The mean distance between CEJ and mid-labial bone crest for all sites was 2.16 mm. CONCLUSION: Labial bone thickness is thin in the vast majority of maxillary anterior teeth. Use of CBCT facilitates planning for immediate implant placement and is helpful in the decision-making process when further bone augmentation is needed.

Fracture of fiber-reinforced composites analyzed via acoustic emission.

This study investigated the fracture resistance of composite resins using a three-point bending test and acoustic emission (AE) analysis. Three groups of specimens (n=15) were prepared: non-reinforced BelleGlass HP composite (NRC), unidirectional (UFRC) and multidirectional (MFRC) fiber-reinforced groups which respectively incorporated unidirectional Stick and multidirectional StickNet fibers. Specimens were loaded to failure in a universal testing machine while an AE system was used to detect audible signals. Initial fracture strengths and AE amplitudes were significantly lower than those at final fracture in all groups (p<0.05). Initial fracture strength of UFRC (170.0 MPa) was significantly higher than MFRC (124.6 MPa) and NRC (87.9 MPa). Final fracture strength of UFRC (198.1 MPa) was also significantly higher than MFRC (151.0 MPa) and NRC (109.2 MPa). Initial and final fracture strengths were significantly correlated (r=0.971). It was concluded that fiber reinforcement improved the fracture resistance of composite resin materials and the monitoring of acoustic signals revealed significant information regarding the fracture process.

Dual jaw treatment of edentulism using implant-supported monolithic zirconia fixed prostheses.

UNLABELLED: This case report describes restoration of the edentulous maxilla and mandible with implant supported fixed prostheses using monolithic zirconia, where the incisal edges and occluding surfaces were made of monolithic zirconia. Edentulism is a debilitating condition that can be treated with either a removable or fixed dental prosthesis. The most common type of implant-supported fixed prosthesis is the metal acrylic (hybrid), with ceramo-metal prostheses being used less commonly in complete edentulism. However, both of these prostheses designs are associated with reported complications of screw loosening or fracture and chipping of acrylic resin and porcelain. Monolithic zirconia implant-supported fixed prostheses have the potential for reduction of such complications. In this case, the CAD/CAM concept was utilized in fabrication of maxillary and mandibular screw-retained implant-supported fixed prostheses using monolithic zirconia. Proper treatment planning and execution coupled with utilizing advanced technologies contributes to highly esthetic results. However, long-term studies are required to guarantee a satisfactory long-term outcome of this modality of treatment. CLINICAL SIGNIFICANCE: This case report describes the clinical and technical procedures involved in fabrication of maxillary and mandibular implant-supported fixed prostheses using monolithic zirconia as a treatment of edentulism, and proposes the possible advantages associated with using monolithic zirconia in eliminating dissimilar interfaces in such prostheses that are accountable for the most commonly occurring technical complication for these prostheses being chipping and fracture of the veneering material.

Development and applications of porous tantalum trabecular metal-enhanced titanium dental implants.

BACKGROUND: Porous tantalum trabecular metal has recently been incorporated in titanium dental implants as a new form of implant surface enhancement. However, there is little information on the applications of this material in implant dentistry. PURPOSE: The purpose of this article is to summarize the contemporary concept on the applications of porous tantalum trabecular metal in implant dentistry. MATERIALS AND METHODS: We therefore review the current literature on the basic science and clinical uses of this material. RESULTS: Porous tantalum metal is used to improve the contact between osseous structure and dental implants and therefore presumably facilitate osseointegration. Success of porous tantalum metal in orthopedic implants led to the incorporation of porous tantalum metal in the design of root-form endosseous titanium implants. The porous tantalum three-dimensional enhancement of titanium dental implant surface allows for combining bone ongrowth together with bone ingrowth, or osseoincorporation. While little is known about the biological aspect of the porous tantalum in the oral cavity, there seems to be several possible advantages of this implant design. This article reviews the biological aspects of porous tantalum-enhanced titanium dental implants, in particular the effects of anatomical consideration and oral environment to implant designs. CONCLUSIONS: We propose here possible clinical situations and applications for this type of dental implant. Advantages and disadvantages of the implants as well as needed future clinical studies are discussed.

Clinical and histological findings of denture stomatitis as related to intraoral colonization patterns of Candida albicans, salivary flow, and dry mouth.

PURPOSE: Multifactorial etiological factors contribute to denture stomatitis (DS), a type of oral candidiasis; however, unlike other oral candidiasis, DS can occur in a healthy person wearing a denture. In this study, we therefore attempt to explore the association between candida, denture, and mucosal tissue using (1) exfoliative cytology, (2) the candidal levels present in saliva, on mucosal tissues and on denture surfaces, and (3) the salivary flow rate and xerostomic symptoms. MATERIALS AND METHODS: A cross-sectional study enrolled 32 edentulous participants, 17 without DS as controls and 15 with DS (Newton's classification type II and III). Participants with systemic or other known oral conditions were excluded. Participants completed a xerostomia questionnaire, and salivary flow rates were measured. Samples of unstimulated whole saliva (UWS) and stimulated whole saliva (SWS) were collected. UWS was used for fungal culturing. Periodic acid-Schiff (PAS) stain and quantitative exfoliative cytology were performed on samples from affected and unaffected mucosa from each participant. Levels of Candida species (albicans and non-albicans) were determined in salivary samples (expressed as colony-forming units, CFU), as well as from swab samples obtained from denture fitting surfaces, in addition to affected and unaffected mucosa. RESULTS: There were no significant differences in salivary flow rates, mucosal wetness, or frequency of reported dry mouth comparing participants with and without DS. Exfoliative cytology of mucosal smears demonstrated significantly higher (p= 0.02) inflammatory cell counts in DS patients, as compared with smears of healthy denture-wearers. Candida albicans was significantly more prevalent in saliva (p= 0.03) and on denture surfaces (p= 0.002) of DS participants, whereas mucosal candidal counts and the presence of cytological hyphae did not show significant difference comparing DS to healthy participants. CONCLUSIONS: In this investigation, we presented a unique group of healthy edentulous patients. This population may reflect the general DS population without systemic or other oral diseases. The prominent etiological factor for DS in this population is the presence of candida in denture and saliva. We found that other factors such as saliva flow/xerostomia, fitting of the denture, and the presence of candida in the mucosa, are less important in this population. Therefore, DS treatments in healthy patients should first focus on sanitization of an existing denture and/or fabrication of a new denture.

Elucidating role of salivary proteins in denture stomatitis using a proteomic approach.

Denture stomatitis (DS) is the most common oral pathology among denture wearers, affecting over one-third of this group. DS is usually associated with C. albicans. However, unlike other oral candidiasis, most DS patients have intact host immunity. The presence of a denture alone is usually sufficient for DS. Saliva and its protein contents can theoretically predispose some denture wearers to DS and others resistant toward DS. Here we proposed for the first time to define salivary proteomic profiles of denture wearers with and without DS. SELDI-TOF/MS analysis suggests that there is a proteomic differentiation among control, localized and generalized DS. Based on initial SELDI-TOF/MS profiling, we further used reversed phase liquid chromatography, MALDI-TOF/MS, and LC-MS/MS to characterize the salivary proteins associated with DS. Nineteen proteins based on SELDI-TOF/MS profiling were found including cystatin-SN, statherin, kininogen-1, desmocollin-2, carbonic anhydrase-6, peptidyl-prolyl cis-trans isomerase A like peptides, cystatin C, and several immunoglobulin fragments. The proteomic content gives evidence of the interaction between host tissue, saliva, and candida. Further examination in larger populations of these proteins may help to gain a better understanding of DS pathological processes and improve DS treatments.