Enhancing dental education: integrating online learning in complete denture rehabilitation.

This study investigated the integration of online learning into complete denture rehabilitation (CDR) training for dental interns, highlighting its impact on their education and readiness for clinical practice. Given that CDR poses significant challenges due to its technical complexity and profound influence on patient well-being, online learning has emerged as a strategic educational tool to enhance interns' knowledge and skills. This research included the administration of a comprehensive questionnaire to 63 dental interns to assess their backgrounds, experiences with online learning, and attitudes toward its application in CDR education. The results revealed strong engagement with online learning, with a majority valuing its flexibility, accessibility, and capacity to facilitate self-paced, individualized learning. Despite the enthusiasm for online modalities, the results identified notable gaps in interns' confidence in and preparedness for performing CDR, highlighting the need for targeted improvements in online curriculum development. By emphasizing the essential role of innovative teaching methods, including virtual reality (VR), this study underscores the need for a balanced educational approach that combines traditional and digital platforms. This strategy aims to prepare future dental professionals for the complexities of modern clinical environments, ensuring that they are well equipped to meet the diverse needs of the edentulous population.

The Effect of Average Value Mounting and Facebow Transfer on Condylar Guidance Settings in a Semi-Adjustable Articulator - A Comparative Study using Digital Lateral Cephalographs in Edentulous Patients.

BACKGROUND: While we attempt to restore occlusion in completely edentulous patients there is a consensus among clinicians to articulate the cast using average value and avoid performing facebow transfer. Various studies question the application of facebow transfer in the fabrication of removable complete denture fabrication. AIM: This study was therefore aimed to study the effect on condylar guidance with casts mounted by the facebow method, Bonwill's method, and radiographic method. METHODS: A cross-sectional study was performed using casts of edentulous patients attending the Department of Prosthodontics. After establishing a tentative jaw relationship using wax occlusal rims in the edentulous participants, the casts were mounted by Bonwill's method and the facebow transfer method to a semi-adjustable articulator. Protrusive records of the subjects were used to program the articulator to obtain the condylar guidance values. Digital lateral cephalographs were made both in centric and protrusive jaw relationships. The mandibular condyles were then traced and overlapped to obtain radiographic values. The condylar guidance values obtained by Bonwill's method, facebow method and radiographic method were compared using Wilcoxon's signed rank test and Mann-Whitney U test. The SPSS Statistics for Windows (Version 21.0. Armonk, NY, USA:IBM Corp.), and, at a probability value of 0.05, the significance of every statistical test was predetermined. RESULTS: Ten edentulous 45-70 year olds participated in the study. The mean discrepancy between radiography and facebow methods was 12.8° for the right side and 12.7° for the left (P < 0.005). The difference between radiography and Bonwill's methods was significant (P < 0.005), with a mean difference of 34.3° for the right side and 34.7° for the left side. The difference between Bonwill's method and the facebow method was significant (P < 0.005), with a mean difference of 21.5° for the right side and 22° for the left side. CONCLUSION: The condylar guidance values obtained by clinical methods (Bonwill's and Facebow) were significantly lesser (P < 0.005) compared to the values obtained by radiographic method.

The wettability of complete denture base materials constructed by conventional versus digital techniques: an in-vitro study.

BACKGROUND: Decreased salivary flow can make the patients uncomfortable with their complete dentures and affects the retention of the dentures. Milling and 3D printing have become an alternative to conventional denture construction techniques. The goal of this study was to evaluate the effect of conventional and digital techniques of the complete denture construction on the denture surface wettability with distilled water and saliva substitute before and after thermocycling. METHODS: A total of 30 specimens were utilized in the present study. Specimens were divided according to the construction techniques into 3 groups (n = 10 each). Group I: Heat-polymerized polymethylmethacrylate (PMMA) group, group II: Milled group, and group III: 3-dimensional (3D)-printed group. All the specimens were subjected to 2000 cycles of thermal aging in a thermocycler. The wettability of all specimens to water and saliva substitute was measured via a contact angle goniometer (Olympus TGHM, Rame-hart Inc, USA) before and after thermocycling. Descriptive statistical analysis, plots, and the Shapiro-Wilk test were used to verify normality for each variable. One-way ANOVA was used to compare the 3 study groups, while paired samples t-test was used to compare the differences within each group (P < .05). RESULTS: The smallest contact angle of drop of water to the denture base specimens before and after thermocycling were recorded in the milled group (53.0 ± 4.77 and 50.27 ± 2.30, respectively), followed by the heat polymerized PMMA group (85.65 ± 4.71 and 65.06 ± 2.27, respectively), and the 3D-printed group (91.34 ± 6.74 and 90.86 ± 8.57, respectively). While the smallest contact angle of drop of saliva substitute to denture base specimens was recorded in the milled group (56.82 ± 2.29 and 34.85 ± 7.51, respectively), followed by the 3D-printed group (72.87 ± 4.83 and 58.14 ± 9.58, respectively) and the heat polymerized PMMA group (83.62 ± 4.12 and 67.82 ± 4.93, respectively). There was statistically significant difference between the groups (P < .05). A significant decline in the average contact angle of drop of saliva has been reported in all groups after thermocycling. The contact angle values differed significantly between saliva substitute and distilled water in both 3D-printed and milled groups after thermocycling (P < .001). CONCLUSIONS: The milled denture base material presented the best wettability to water and saliva substitute than the 3D-printed and the heat-polymerized PMMA materials. Saliva substitutes improve the wetting ability of denture base materials manufactured by CAD/CAM compared with water.

The Influence of Removable Complete Denture on Pro-Oxidant Antioxidant Balance and Redox-Sensitive Inflammation Biomarker NF-ĸB in the Oral Cavity: An Interventional Follow-Up Study.

OBJECTIVES: Oxidative stress, an imbalance between the body's natural antioxidant defenses and the production of reactive oxygen species (ROS), can result in serious oral diseases, including oral cancer, periodontal diseases, and oral lichen planus, through the activation of the redox-sensitive transcription factors and inflammation. The purpose of this study was to assess the potential effects of a removable complete denture on the levels of oxidative stress markers, such as lipid peroxidation (MDA), advanced oxidation protein products (AOPP), and catalase, and the quantitative expression of the redox-sensitive transcription factor NF-κB p65 subunit. MATERIALS AND METHODS: This interventional follow-up study enrolled 40 participants of both sexes aged 28-78 years, with a median age of 56 years, where unstimulated saliva was collected before denture placement, immediately after the denture placement, and 24 h, 7 days, and 30 days after the denture placement. The most prominent ROS overproduction was reported on the seventh day (p < 0.05), followed by a significant fall in antioxidative defense. RESULTS: The NF-κB p65 subunit, whose expression pattern was highest in the same time period on the seventh day, serves as a signaling molecule for redox imbalance due to ROS production. Over the next 30 days, its levels remained moderately increased compared to the basal value, which may influence pro-inflammatory pathways and the integrity of oral tissue components. These alterations may be induced by the dentures, which can produce high pressures on the supporting tissues or by the synthetic materials used for producing the dentures. CONCLUSION: Our research may help to clarify the potential pathways by which oxidative stress and redox-sensitive inflammatory mediators, as well as mechanical and chemical irritants, may serve as risk factors for premalignant lesions in the mouth. Further research on this topic is required to understand the molecular mechanisms behind the relationship between inflammation and oral premalignant lesions caused by mechanical and chemical irritation.

Clinical decision of centric relation.

Centric relation (CR) was used in the complete dentures for edentulous jaws firstly. Then, CR was gradually applied in the clinical diagnosis and treatment of dentate jaws. Regarding the application of CR in dentate jaws, there are many doubts about its rationality. For instance, should CR be the core of diagnosis and treatment of temporomandibular disorders? Should CR be used as the jaw position of establishing occlusion in occlusal reconstruction? Should CR serve as the target jaw position in orthodontic treatment? Meanwhile, varieties of CR clinical applications are objective. According to the existing evidence, this paper summarizes the applicable conditions of several main clinical situations with little controversy. We preliminarily put forward the decision tree for the clinical application of CR, which can be used as a reference in clinical practice.

Evaluation of the effect of thermocycling on the trueness and precision of digitally fabricated complete denture bases.

BACKGROUND: While many denture base materials are currently available on the market, little data exists regarding their dimensional stability after exposure to the oral environment. This study aimed to evaluate the effect of thermocycling on the trueness and precision of milled, 3-dimensional (3D)-printed, and conventional digitally fabricated complete denture bases (CDBs). METHODS: A completely edentulous maxillary stone model was scanned to generate a standard tessellation language (STL) file; this was imported into metal-milling-machine software (Redon Hybrid CAD-CAM metal milling machine, Redon, Turkey) to produce a metal model for fabricating 30 CDBs. These were divided into three groups (n = 10 in each) according to the construction technique: group 1, CAD-CAM milled CDBs; group 2, 3D-printed CDBs; and group 3, conventional compression molded CDBs. All CDBs were scanned after fabrication and evaluated before and after thermocycling using superimposition. The data were analyzed using a one-way ANOVA, Tukey's post hoc test, and a paired t-test. RESULTS: The level of trueness between the CAD-CAM milled, 3D-printed, and compression molded CDBs showed significant differences before and after thermocycling (P < 0.05). Group 1 showed the highest degree of trueness before and after thermocycling, group 3 exhibited a higher degree of trueness than group 2 before thermocycling, and group 2 had a higher degree of trueness than group 3 after thermocycling. There was a significant difference in the precision for each CDB type before and after thermocycling (P < 0.05). CONCLUSION: The trueness of the CAD-CAM milling system in complete denture (CD) fabrication is superior to that of the 3D printing and conventional compression molding systems before and after thermocycling. Thermocycling had a significant effect on the precision of all CDB types. The compression molding system in CD construction is the most negatively affected via thermocycling with regard to the measures of trueness and precision. CLINICAL TRIAL NUMBER: Not applicable, no human participants were involved.

Evaluation of tissue conditioner-assisted complete denture restoration: A randomized controlled clinical trial.

PURPOSE: To evaluate the clinical effect of three impression methods, conventional, closed-mouth, and tissue conditioner, on complete denture fabrication. METHODS: 60 subjects (edentulous with severely resorbed alveolar ridges - Atwood classification III or IV) who visited the Prosthodontic Department of Wuxi Stomatology Hospital, China, between January 2022 and June 2023, were selected for this study. The subjects were randomly divided into three groups of 20: a conventional impression group (CI group), a closed-mouth impression group (CM group), and a tissue conditioner group (TC group). Three months after denture restoration was completed, denture quality was assessed by clinicians in terms of marginal extension, retention, and stability. In addition, patients completed the oral health impact profile-edentulous (OHIP-EDENT) questionnaire to provide subjective satisfaction evaluations of the final denture restoration outcomes. RESULTS: The comprehensive denture quality evaluation results showed that the TC group had the lowest score, which was significantly lower than that of the CM (P= 0.014) and CI (P< 0.001) groups. The average score of the CM group was also significantly lower than that of the CI group (P= 0.004), indicating that tissue conditioner restoration was the most effective method. The OHIP-EDENT scores gradually decreased across the groups from CI to CM to TC (P= 0.001), indicating patients' oral health was significantly improved using tissue conditioner. CLINICAL SIGNIFICANCE: Tissue conditioner is a suitable dynamic functional impression method. It can significantly improve the effects for edentulous patients and increase their satisfaction.

Dimensional reliability in CAD/CAM production of complete denture bases: A comparative study of milling and various 3D printing technologies.

This study aims to assess the dimensional accuracy of complete denture bases fabricated from different CAD/CAM technologies and a conventional method, including milling (CNC), PolyJet (PJ), laser sintering (SLS), digital light processing (DLP), and injection molding (IM). It also examines the influence of the removal of technology-specific connectors or support structures when present. Denture base surfaces were digitized using a laboratory scanner, and virtual measurement points were calculated with tetrahedral reference geometries. Defined distances were measured in all spatial directions and compared to design data (p<0.05), revealing significant differences in sagittal (p=0.004), transversal (p<0.001), and vertical (p<0.001) dimensions. Connector removal had no significant impact for CNC but significantly affected DLP. All technologies yielded clinically acceptable results, with CNC milling demonstrating the best overall outcome.

Comparison of perceived masticatory ability in completely edentulous patients treated with thermoplastic complete denture versus single implant-retained mandibular overdenture: a single-center prospective observational study.

Background: This study aimed to compare the perceived masticatory ability (PrMA) in completely edentulous patients (EDPs) with thermoplastic conventional complete dentures (CDs) versus single implant-retained mandibular overdentures. Methods: The current study was conducted in the outpatient Prosthodontic Clinic, Faculty of Dental Medicine, Al-Azhar University, Cairo, Egypt. PrMA was evaluated in 45 completely edentulous patients (46% males, mean age 50.4 ± 4.7 years). Each patient received a thermoplastic PMMA complete denture (Polyan IC TM Bredent GmbH & Co.KG, Germany). The PrMA was evaluated at one-month and six-month intervals of denture use. An immediate loading single implant was placed into the mid-symphyseal for each patient, and the denture was adjusted. Subsequently, the PrMA was reevaluated after one month and six months. The data were collected and statistically analyzed using the SPSS@V25 to assess the changes in PrMA. Results: The PrMA demonstrated improvement after six months of thermoplastic conventional denture use. However, this improvement was not statistically significant (p = 0.405). In addition, the PrMA showed a substantial increase following a single implant placement at one and six months (p < 0.001) of the overdenture use compared to the conventional denture. The PrMA insignificantly improved (p = 0.397) after six months of the single implant retained overdenture use. Discussion: The study's findings indicate that using immediate loading single implant-retained mandibular overdentures significantly improved PrMA in completely edentulous patients.

Impact of Denture Use on Oral Health-Related Quality of Life in Yemeni Patients: A Cross-Sectional Analysis.

BACKGROUND We used the 14-item Oral Health Impact Profile-14 (OHIP-14) questionnaire to evaluate the association between sociodemographic variables and oral health-related quality of life in 241 wearers of removable partial or complete dentures attending a single center in Yemen. MATERIAL AND METHODS A total of 241 partial dentures (PD) and complete dentures (CD) wearers were enrolled from the Department of Prosthodontics at the Faculty of Dentistry, Sana'a University, and the University of Science and Technology. Data were collected before the commencement of denture wearing and after 3-6 months of denture use. The questionnaire consisted of sociodemographic information and denture type, and another for the OHIP to assess oral health-related quality of life (OHRQoL), oral health impact profile scale comprises 7 subscales, each evaluating different aspects of oral health and functionality. Descriptive statistics were calculated for participants. Independent t tests were performed to compare different patient groups, focusing on PD and CD wearers. Paired-sample t tests were used to examine changes within patient groups before and after removable denture use. RESULTS Among all participants, 67.6% were male, wearers of CDs were 74.6% male, PDs were 58.3%, and was consistent for CD (71.0%) and PD (72.8%) wearers. The wearing prostheses significantly impacted the OHRQoL of patients using both PDs and CDs (P<0.01). Among CD wearers, 4 of these subscales (3-6) were statistically significant, but the handicaps subscale showed evident reductions in physical pain after treatment among PD wearers. CONCLUSIONS Wearing dentures positively affects the OHRQoL of patients, influencing various aspects of their health, including functional, physical, psychological, and social well-being.