Low-fidelity Medical Simulation: Relevance in the Learning of Dental Students in South Africa.

BACKGROUND: Healthcare embraces simulation's learning boost, from medicine to dentistry. But can it unlock the secrets of intricate fixed prosthodontics? This study takes a pioneering step to find out. AIM: To evaluate low-fidelity medical simulation (LFMSim) in fixed prosthodontics by assessing its effectiveness in training corono-radicular preparations and by exploring participants' perceptions of LFMSim as an innovative teaching tool for developing pre-practice skills. MATERIALS AND METHODS: A prospective, descriptive study was executed to explore these facets among 6th-year students. The Debriefing Assessment for Simulation in Healthcare (DASH©) evaluation grid, student version, was employed for assessment. The study encompassed one week, from 03/03/2023 to 10/03/2023. RESULTS: The study involved 28 learners with an average age of 23 and a sex ratio of 0.33, half of whom had prior exposure to simulation sessions. Seventy-five percent of participants watched the instructional video a day before the simulation, with nine expressing presession stress. Overall, 19% of students found the session as expected, while 43% considered it better than anticipated. Satisfaction levels varied, with 50% indicating they were "rather satisfied," and 46.4% expressing absolute satisfaction. The Debriefing Assessment using DASH yielded an average score of 4.85. CONCLUSION: The study's findings shed light on the effectiveness of LFMSim in training corono-radicular preparations and post-space impressions for fixed prosthodontics among 6th-year students. The varied satisfaction levels and the emphasis on debriefing discussions suggest avenues for improving simulation sessions in the future. CLINICAL SIGNIFICANCE: These insights are pertinent for educators and institutions aiming to enhance dental education through innovative teaching tools like simulation. By refining simulation sessions based on debriefing feedback, educators can better prepare students for real-world clinical scenarios, ultimately improving patient care outcomes. This highlights the practical importance of incorporating simulation-based learning into dental curricula. How to cite this article: Hadyaoui D, Boukhris H, Riahi Z, et al. Low-fidelity Medical Simulation: Relevance in the Learning of Dental Students in South Africa. J Contemp Dent Pract 2024;25(5):463-472.

Postgraduate Training in Prosthodontics: Residents' and Supervisors' Perspectives on Current Training: A Cross-Sectional Study.

OBJECTIVE: To identify postgraduate (PG) prosthodontic trainees' and supervisors' introspective views regarding prosthodontic education and clinical training. STUDY DESIGN: Cross-sectional survey. Place and Duration of the Study: The Aga Khan University Hospital, Karachi, from May to October 2021. METHODOLOGY: Data regarding the trainee induction process, teaching and learning practices, research interests, frequency of assessment, and trainees' satisfaction levels with the adequacy of didactic and clinical training in their centres were collected from Prosthodontic PG trainees and supervisors in Pakistan using REDCap software and analysed using SPSS 23.0. Frequencies of the observed responses from both populations were reported, and associations among private and public training centres were studied with Chi-square (or Fisher's exact). Differences in satisfaction levels across theoretical and clinical training domains were assessed with Mann- Whitney U test. RESULTS: Out of 17 supervisors and 104 PG trainees, 30% reported having a supervisory board in their institute. Most participants had entry tests conducted in their centres. The interference of influential sources during trainee induction was reported by 88.2% of the supervisors, while 66.7% trainees expressed the need for such influence to acquire training. Simulation-based teaching was available to 43.2% of trainees, 83% expressed interest in publishing research and 85% in publishing cases. Trainees were overall satisfied with their didactic and clinical training, whereas their satisfaction level was found neutral with theory and clinical training in maxillofacial-prosthodontics and clinical training of occlusion and temporomandibular disorders. CONCLUSION: The results emphasise the need for regulation and monitoring of the trainee induction process, quality of training, and frequent assessments in the prosthodontics postgraduate training programmes across Pakistan. KEY WORDS: Prosthodontics, Programme evaluation, Graduate dental education, Postgraduate dental education, Postgraduate medical education.

[Application of PDCA theory in prosthodontic for standardized training of dental residents].

PURPOSE: To evaluate the application effect of PDCA cycle teaching mode in the standardized training and teaching of dental residents in prosthodontics speciality. METHODS: A total of 46 dental residents in Shanghai Stomatological Hospital from 2020 to 2022 were selected as the research subjects, and divided into experimental group (n=23) and control group(n=23), the control group adopted conventional teaching method, while the experimental group adopted PDCA cycle teaching method on the basis of the control group. The theoretical assessment, clinical operation assessment and satisfaction of the teaching effect of the two groups of residents were compared with SPSS 20.0 software package. RESULTS: The theoretical assessment, clinical operation assessment and satisfaction of the residents in the experimental group were all higher than the data obtained in the control group, and the difference was statistically significant(P＜0.05). CONCLUSIONS: Compared with the traditional model teaching group, PDCA cycle teaching model can train the dental residents more personalized, better improve the clinical comprehensive quality and professional level, and achieve good feedback effect.

The Effectiveness of Technology-Enhanced Learning in Prosthodontic Education: A Systematic Review.

OBJECTIVE: To compare the effectiveness of technology-enhanced learning (TEL) with traditional learning in prosthodontic education. METHODS: The protocol was registered before commencement [CRD42023390277]. The search was conducted to identify randomized controlled trials (RCTs) focused on comparative assessment of TEL and traditional learning in prosthodontic education up to 6 June 2024. A comprehensive search strategy was formulated, encompassing multiple electronic databases. Screening, data extraction and risk of bias assessment using the Cochrane tool (RoB 2) were performed. Educational outcomes were evaluated by Kirkpatrick's four-level evaluation model. RESULTS: Of 2830 records identified, 14 RCTs were included. All the trials were judged at high risk of bias or had some concerns. The included studies assessed the short-term benefits of various TEL approaches, including e-learning, blended learning, video demonstration specialized self-evaluation software and virtual reality simulation in prosthodontic education for undergraduates. Promising results were found in individual studies, particularly in terms of perceived learning conditions with problem-based learning (PBL) and self-reported understanding and confidence when using video demonstrations. Most studies reported comparable outcomes to traditional learning in practical skills assessments, while the results regarding the acquisition of theoretical knowledge through the incorporation of TEL approaches were contradictory. One study reported promising results in perceived learning conditions with the PBL approach, as well as improved self-reported understanding and confidence with the use of video demonstrations. Furthermore, there was a limited number of studies assessing the effect of TEL approaches on students' behaviour. CONCLUSION: There is a lack of high-quality evidence to support the adoption of TEL approaches in prosthodontics. However, the incorporation of virtual reality simulation has demonstrated promising results, particularly in improving practical clinical skills.

Epidemiological profile of patients attending the maxillofacial prosthodontics unit at Ibn Sina University Hospital in Rabat, Morocco: a cross-sectional study.

Introduction: the present study aimed to establish an epidemiological profile of patients consulting the unit of maxillofacial prosthodontics in Rabat. Results deriving from this study will help enhance the quality of patient care in our center and can also serve as a comparison tool with other maxillofacial teams around the world. Methods: during 11 months all patients consulting the unit of maxillofacial prosthodontics in our center were included. We opted for a questionnaire with 3 variables: socio-demographics, clinical examination data, and the type of prosthetic treatment adopted. The study was conducted in the Department of Removable Prosthodontics in the Center of Consultation and Dental Treatment of Rabat Morocco (CCDTR) from September 2020 to July 2021. Results: the study population consisted of 91 patients, with a majority of male patients at 53% (n=48). During our study period, the proportion of patients under one-year-old was predominant, accounting for 38.4% (n=35) of the total sample. Among the patients in the sample, 72.5% (n=66) had no profession, while 66% (n=60) had a low income. Regarding medical insurance, the majority of our patients, 85.5% (n=78), were covered by Public Health Insurance for the Low-income Population (PHILP). Among the total sample, 57.1% (n=52) consulted for a combination of pain function and aesthetics. Additionally, 61.5% (n=56) were referred by teaching hospitals. For the type of oro-facial defect, 52.7% (n=48) of the sample consisted of newborns with congenital facial cleft. Out of the 91 patients, 36 had maxillofacial tumors, with 47.6% (n=17) of them presenting squamous cell carcinoma. Furthermore, 63.7% (n=58) of the prosthetic treatments adopted involved presurgical orthopedic treatments for newborns with facial cleft. Conclusion: the study on the epidemiological profile of patients attending the maxillofacial prosthodontics unit at Ibn Sina University Hospital in Rabat, Morocco provides important insights. The findings highlight the predominance of male patients and the prevalence of oro-facial defects in newborns. Socioeconomic factors, such as low income and lack of profession, are significant considerations. The majority of patients are covered by the PHILP, indicating the importance of medical insurance. These findings contribute to improving healthcare planning and specialized care for this patient population.

Digital technology implementation in prosthodontics postgraduate programs in Saudi Arabia: a multi-institutional survey of program directors.

OBJECTIVE: To assess the current status of digital technology (DT) implementation in prosthodontics post-graduate (PG) programs in Saudi Arabian dental institutions. METHODOLOGY: A 19-item survey was created using Google forms and the link was emailed to the 29 prosthodontics PG program directors (advanced clinical training and joint program) in Saudi Arabia. The questionnaire contained five Sect. 1) didactic training and DT usage in PG preclinical, clinical and laboratory training, 2) incorporation of DT in PG program, 3) utilization of DT and the types of cases treated by PG students during their course, 4) information on the faculties involved in prosthodontics PG education, and 5) potential challenges encountered and program directors' satisfaction of the PG program. Descriptive statistics was used to present the frequencies and proportions, and Chi square inferential test was used to compare the participants' response based on the type of PG programs (α = 0.05). RESULTS: Only 28 program directors responded to the survey, yielding a 95.5% response rate. Among the program directors, 24 (85.7%) and 4 (14.3%) directors supervised the advanced clinical training and joint programs, respectively. Among the DT, CAD/CAM was the most used technology (50-80%), followed by intra-oral scanning (28-96%). Digital technology implementation was largely limited by lack of resources or equipment (67%), cost (53%) and scarcity of PG teaching staff (46%). A significant difference was observed between the programs regarding the mandatory use of DT for their cases (p = 0.03). CONCLUSIONS: This multi-institutional survey of program directors revealed that DT is continuously implemented in the last few years. Saudi dental institutions must prioritize implementing and utilizing DT in PG training to graduate competent prosthodontists in this fast-paced digital era. While DT is pivotal in dental education, its implementation is limited in many institutions due to resources or equipment, cost, and lack of trained faculty.

Evaluation of user experience and satisfaction with workplace-based assessments (WPBAs) in dental postgraduate programmes.

Objectives: To explore the experience of and satisfaction with workplace-based assessment tools among dental postgraduate trainees. METHODS: The cross-sectional study was conducted from March to October 2022 at the Aga Khan University Hospital, Karachi, and comprised all Operative Dentistry, Prosthodontics and Orthodontics postgraduate trainees. A questionnaire with both open-ended and closed-ended questions was used to record the experiences and satisfaction level of the dental residents who had earlier been subjected to workplace-based assessment. Data was analysed using SPSS 20, while thematic analysis was used for open-ended questions. RESULTS: Of the 20 Subjects, 15(75%) were females. Also, 11(55%) participants had received prior training for workplacebased assessment. There were 16(80%) residents who were satisfied with workplace-based assessment tools in the dental residency programme, 15(75%) agreed that the tools improved their clinical skills and helped them identify their weak areas, all the 20(100%) participants said the feedback given to them was constructive, 18(90%) reported that they were allowed to put in their views. However, 7(35%) participants reported that being observed adversely affected their performance. CONCLUSIONS: Dental residents generally gave positive feedback related to workplace-based assessment tools in a clinical setting.

[Need for prosthodontics of permanent teeth in children aged 8-18 years]. / Nuzhdaemost' v ortopedicheskom lechenii postoyannykh zubov detei 8­18 let.

OBJECTIVE: To reveal need for prosthodontics in permanent teeth in children aged 8-18 years. MATERIALS AND METHODS: The study was performed in Khimki Dental Municipal Clinic. Dental examination and radiological studies were conducted in 97 primary patients aged 8-18 years. Indications for prosthodontics in permanent teeth were occlusal deterioration index more than 40% and crown decay of more than 50% in incisors and canines. Additional features were registered including DMFT index, the presence of extracted teeth and teeth after root canal treatment, as well and teeth with extensive restorations with resins and marginal seal quality. RESULTS: From 97 primary patients (27.8%) children needed prosthodontics in permanent teeth (in average 2.3±2.1 teeth): 1 tooth in 10 children, 2 teeth in 11 children, 3 teeth in 1 child, 4 teeth in 3 children and 4 teeth in 2 children. Mean DMFT was 8.1±4.5 teeth. Six children already had extracted permanent teeth (9 teeth in total). Half of the teeth (49.2%) which needed orthodontic treatment had history of root canal treatment while 46% needed primary or secondary endodontic treatment. Occlusal deterioration index was more than 40% in 41.3% of cases, more than 60% in 49.2% of teeth and more than 80% in 9.52% of teeth. From all the teeth restored with composite resins 41.7% had good marginal seal but 58.3% showed macroscopic signs of marginal leakage. CONCLUSION: Our study shows high percentage of adolescents having need for prosthodontics in permanent teeth and unjustified widening of indications for direct resin restorations in this group of patients.

Precise jaw relation recorder: An innovative device for prosthodontic rehabilitation.

BACKGROUND: The orchestration of jaw relations in edentulous scenarios poses a significant challenge, demanding acumen, and expertise from the clinician. A myriad of devices, substances, and methodologies are employed to gauge the transverse, vertical, and horizontal spectrums of jaw relations. Traditionally, a synthesis of assorted devices and techniques has been requisitioned to chronicle the spatial dynamics between the maxilla and mandible. Yet, the absence of a solitary apparatus capable of concurrently documenting the triad of jaw relations has been a notable lacuna in prosthodontic rehabilitation. PURPOSE: This discourse expounds on an innovative contrivance, termed the Precise Jaw Relation Recorder. This pioneering instrument is adept at capturing the tripartite jaw relation processes: the occlusal plane's alignment in parallelism to the ala-tragus line, the vertical dimension at repose, and the occlusion as well as the centric relation. The device's strategic utility lies in its ability to facilitate the creation of prostheses that are not only functionally superior but also aesthetically more pleasing. CONCLUSION: Its implementation is a stride toward refining the accuracy of prosthodontic outcomes, thereby elevating the standard of patient care in dental practice.

Intraoral scanners in implant prosthodontics. A narrative review.

OBJECTIVES: To review the developments in intraoral scanner (IOS) technologies applied in implant prosthodontics, emphasizing their influence on the accuracy of digital impressions, occlusal registrations, and the fit of implant-supported restorations. DATA: A collection of published articles related to implant prosthodontics, the accuracy of digital impressions, occlusal registration, and the fit of implant-supported fixed restorations. SOURCES: Three search engines were selected: Medline/PubMed, EBSCO, and Cochrane. A manual search was also conducted. STUDY SELECTION: A literature search screened relevant databases and journals for studies on IOS applications in digital implant prosthodontic workflows from Dec 2018 to Dec 2023. Inclusion criteria encompassed randomized control trials, clinical trials, case series, and in vitro research focused on the use of IOS in digital implant prosthodontics. CONCLUSIONS: The increased utilization of digital dental technologies has led to significant integration of digital implant prosthodontic workflows into clinicians' clinical practice. Several variables affect the accuracy of digital impressions generated by IOS. Generally, the prevailing opinion in academic papers is that digital workflows are suitable for addressing short-span implant-supported restorations. However, when it comes to long-span defects, the accuracy of digital workflows is still a matter of debate. Digital bite registration is an integral part of the workflow. It depends mainly on the defect size and location, scan strategy, anatomical tooth variations, overbite and other factors. The overall fit of digitally prefabricated implant restorations comprises of proximal, occlusal contacts and how accurately the restoration connects with implants. Research methodologies need standardization for further validation. CLINICAL SIGNIFICANCE: In clinical practice, it is essential to have a thorough and up-to-date comprehension of various factors that can affect the accuracy of digital impressions and the fit of the final prosthesis in implant prosthodontics.

How the Study of "Periodontal Prosthesis" Advances Public Oral Health.

As Penn Dental School prepares for its Commission on Dental Accreditation (CODA)-approved dual-certificate periodontics/prosthodontics program, this article looks back at the roots of these specialties at the university via the renowned Periodontics and Periodontal Prosthesis program co-founded byCompendium's founding editor Dr. D. Walter Cohen as seen through the eyes of one of its graduates. The article commends the program's impact on public health today.

The Potential of Artificial Intelligence in Prosthodontics: A Comprehensive Review.

Prosthodontics is a dental subspecialty that includes the preparation of dental prosthetics for missing or damaged teeth. It increasingly uses computer-assisted technologies for planning and preparing dental prosthetics. This study aims to present the findings from a systematic review of publications on artificial intelligence (AI) in prosthodontics to identify current trends and future opportunities. The review question was "What are the applications of AI in prosthodontics and how good is their performance in prosthodontics?" Electronic searching in the Web of Science, ScienceDirect, PubMed, and Cochrane Library was conducted. The search was limited to full text from January 2012 to January 2024. Quadas-2 was used for assessing quality and potential risk of bias for the selected studies. A total of 1925 studies were identified in the initial search. After removing the duplicates and applying exclusion criteria, a total of 30 studies were selected for this review. Results of the Quadas-2 assessment of included studies found that a total of 18.3% of studies were identified as low risk of bias studies, whereas 52.6% and 28.9% of included studies were identified as studies with high and unclear risk of bias, respectively. Although they are still developing, AI models have already shown promise in the areas of dental charting, tooth shade selection, automated restoration design, mapping the preparation finishing line, manufacturing casting optimization, predicting facial changes in patients wearing removable prostheses, and designing removable partial dentures.

Minimally invasive prosthodontics using the concept of prosthetically guided orthodontics.

OBJECTIVE: This case report aims to present how digital technology can be employed to plan the orthodontic movement of teeth into their final positions for prosthodontic rehabilitation. An interdisciplinary approach to treatment planning and the result of prosthodontic treatment involves the cooperation of an orthodontist and a prosthodontist. When planned to achieve optimal results for a minimally invasive and functional prosthodontic treatment, orthodontic pretreatment provides superior esthetic results and favorable long-term success. CLINICAL CONSIDERATIONS: The orthodontic movements of the teeth were planned so that the prosthodontist could reconstruct an optimally functional and esthetic occlusion while preserving the hard dental tissues. The orthodontic pretreatment minimized the need to prepare the teeth, avoiding any mucogingival surgery to improve the gingival architecture. CONCLUSIONS: In complex clinical cases, it is essential to evaluate the advantages of an orthodontic pretreatment before starting a prosthodontic treatment. This pretreatment can help preserve dental tissues, reduce or eliminate the need for surgical intervention, and achieve long-term stability and esthetic results. CLINICAL SIGNIFICANCE: This case clearly shows the benefits of orthodontic pretreatment for prosthodontic outcomes. With modern digital tools, such an orthodontic pretreatment should become standard clinical practice when planning a complex clinical case.

Pediatric dentistry, prosthodontics, and oral and maxillofacial surgery residents' stress, career satisfaction, and gender-based discrimination/harassment.

OBJECTIVES: Dental residents experience high stress in their demanding programs and gender-based harassment/discrimination can contribute to their stress. The objectives were to compare stress, satisfaction, experienced sexual harassment and observed discrimination of women in dental graduate programs with high, medium, and low percentages of women and to explore relationships between these constructs of interest. METHODS: Note that, 112 pediatric dentistry (PD), 44 prosthodontics, and 56 oral and maxillofacial surgery (OMS) residents responded to a survey. RESULTS: PD residents had the lowest personal life-related stress (4-point scale with 4 = very stressful: PD = 2.99/P = 3.67/OMS = 3.56; p < 0.001), faculty-related stress (2.68/3.66/3.03; p < 0.001), lack of confidence-related stress (2.79/3.31/2.96; p < 0.01) and academic stress (2.65/3.24/3.02; p < 0.001), while prosthodontics residents had the highest stress levels. The average frequency of experiencing sexual harassment was highest for OMS residents and lowest for PD residents (5-point scale with 1 = never: 1.15/2.62/2.74; p < 0.001). PD residents observed least and OMS residents most frequently that female residents were treated less positively by other residents because of their gender (1.59/2.57/3.00; p < 0.001). Prosthodontics residents had the lowest job satisfaction score (5-point scale with 1 = lowest satisfaction: 4.12/3.14/4.20; p < 0.001). The more frequently male and female residents experienced sexual harassment, the higher their personal life-related stress, faculty-related stress, lack of confidence-related stress, and academic stress, and the lower their career satisfaction, specialty content satisfaction, and stress-related satisfaction. Women's frequencies of observed gender-based discrimination were associated with higher stress and lower satisfaction, while men's frequencies of these observations were not associated with stress, but associated with increased satisfaction. CONCLUSIONS: Dental residents' stress, career satisfaction, experienced sexual harassment, and observed discrimination of women residents differ depending on the dental specialty program. Both male and female residents report more stress and less satisfaction the more they experience sexual harassment. The more women observe discrimination of women, the more stressed and the less satisfied they are. For men, the frequencies of these observations are not associated with stress, but positively associated with increased satisfaction.

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.

[Effect of printing orientation on physical and mechanical properties of 3D printing prosthodontic base resin materials].

OBJECTIVE: To analyze the influence of forming direction on the surface characteristics, elastic modulus, bending strength and fracture toughness of printed parts and the relationship between forming direction and force direction, and to provide scientific basis and guidance for the clinical application of oral denture base resin materials. METHODS: The 3D printing technology was used to print denture base resin samples. The shape and size of the samples referred to the current standard for testing conventional denture base materials. The samples used for physical performance testing were cylindrical (with a diameter of 15 mm and a thickness of 1 mm) and printed at different angles along the Z axis (0°, 45°, 90°). Scanning electron microscope was used to observe the microscopic topography of the different samples. The color stability of different samples was observed by color stabilizer. The surface roughness of the samples was analyzed by using surface roughness tester. The Vickers hardness was measured to analyze the hardness of the samples. The samples used for mechanical performance testing were rectangular (elastic modulus and bending strength: A length of 64 mm, a width of 10 mm, and a height of 3.3 mm; fracture toughness: A length of 39 mm, a width of 8 mm, and a height of 4 mm), divided into two groups: W group and H group. The W group was printed from the bottom up along the Z axis with the length × width as the bottom surface parallel to the X, Y axis plane, while the H group printed from the bottom up along the Z axis with the length × height as the bottom surface parallel to the X, Y axis plane. The forming angles of both groups were equally divided into 0°, 45°, and 90°. The elastic modulus, bending strength and fracture toughness of different samples were studied through universal mechanical testing machine. SPSS 22.0 software was used for statistical analysis. RESULTS: The microscopic topography and roughness of different samples were closely related to the printing direction, with significant differences between the 0°, 45°, and 90° specimens. The 0° specimens had the smoothest surface (roughness < 1 µm). The surface of the 45° specimen was the roughest (roughness>3 µm). The microhardness of the 0° sample was the best [(196.13±0.20) MPa], with a significant difference compared with the 90° sample [(186.62±4.81) MPa, P < 0.05]. The mechanical properties of different samples were also closely related to the printing direction. The elastic modulus, bending strength, and fracture toughness of the 45° samples in the W group were the highest compared with the other groups. The results of elastic modulus showed that in the H group, the 45° specimens had the highest elastic mo-dulus, which was significantly different from the 0° and 90° specimens (P < 0.05). The elastic modulus of 0° and 45° specimens in the W group were higher than those in 90° specimens (P < 0.05). The bending strength results showed that there was no significant difference between the specimens from dif-ferent angles in the H group. The bending strength of the 90° specimens in the W group was the smallest, and there was a significant difference between 90° and the 0° and 45° specimens (P < 0.05); And the bendind strength of the 0° and 45° specimens in the W group was significantly higher than that of the 0° and 45° specimens in the H group (P < 0.05). The fracture toughness results showed that the fracture toughness of the H group specimens was lower than 1.9 MPa m1/2, which was specified in the denture base standard. The 45° samples in the W group were the highest, with significant differences compared with the 0° and 90° samples (P < 0.05). And the 90° samples of the W group specimens were lower than 1.9 MPa m1/2. And the fracture toughness of the 45° specimen in the W group was significantly higher than that of all the specimens in the H group (P < 0.05). CONCLUSION: The 0° samples had relatively better physical properties. The 45° samples had the best mechanical properties. But the fracture toughness of specimens (H group and 90° samples of W group) did not yet meet clinical requirements. That indicated that the characteristics of the 3D printing denture base resin were affected by the printing direction. Only when the performance of the printed samples in all directions met the minimum requirements of the standard, they could be used in clinical practice.

Assessment of reproducibility and influence of different dental specialties on functional implant prosthodontic score: A prospective clinical study analyzing single-unit implant crowns.

AIM: Implant therapy in partially edentulous patients has become the most adapted and predictable treatment modality. The success rate of implants has been measured in terms of esthetic, biological, and technical factors such as radiographic bone loss, prosthetic complications, and stability. Despite the existence of several indices for the esthetic assessment of implant crowns, a need for functional evaluation of the implant crown with an objective and reproducible score has arisen. The study aims to validate the reproducibility of the functional implant prosthodontic score (FIPS) and the influence exerted by different dental specialties while evaluating posterior single-unit implant crowns. STUDY SETTING AND DESIGN: This was a prospective clinical study. MATERIALS AND METHODS: Fifteen patients with cement-retained single-implant crowns in the posterior region of the jaws were included. Eight examiners, two prosthodontists, two periodontists, two oral surgeons, and two orthodontists evaluated 15 photographs of single-unit implant crowns during the 1-year follow-up examination. The examiners assessed the photographs for FIPS, which includes five parameters for objectively evaluating the single-unit implant crowns. Assessments were performed twice at a gap of 4 weeks. STATISTICAL ANALYSIS USED: Pearson's correlation with a 95% confidence interval was calculated for the intra-examiner and the Kruskal-Wallis test for inter-examiner reproducibility. RESULTS: The mean total FIPS scores for all included examiners were 7.133 for time T1 and 7.074 for time T2, showing a strong Pearson correlation coefficient for intra-examiner reproducibility. No significant difference was analyzed among different specialties with statistically significant values of the Kruskal-Wallis test. CONCLUSION: Intra- and inter-examiner analysis showed very consistent results during the reproducibility assessment of FIPS. The results validated the use of FIPS as a long-term predictive functional evaluation tool for the single-implant crowns in posterior sites irrespective of the effect of different dental specialties. It could be used for risk estimation and prognosis for long-term survival and performance of implant crowns.