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The literature presents insufficient data evaluating the displacement and micromotion effects resulting from the combined use of tooth-implant connections in fixed partial dentures. Analyzing the biomechanical behavior of tooth-implant fixed partial denture (FPD) prothesis is vital for achieving an optimum design and successful clinical implementation. The objective of this study was to determine the relative significance of connector design on the displacement and micromotion of tooth-implant-supported fixed dental prostheses under occlusal vertical loading. A unilateral Kennedy class I mandibular model was created using a 3D reconstruction from CT scan data. Eight simulated designs of tooth-implant fixed partial dentures (FPDs) were split into two groups: Group A with rigid connectors and Group B with non-rigid connectors. The models were subjected to a uniform vertical load of 100 N. Displacement, strain, and stress were computed using finite element analysis. The materials were defined as isotropic, homogeneous, and exhibiting linear elastic properties. This study focused on assessing the maximum displacement in various components, including the bridge, mandible, dentin, cementum, periodontal ligament (PDL), and implant. Displacement values were predominantly higher in Group B (non-rigid) compared to Group A (rigid) in all measured components of the tooth-implant FPDs. Accordingly, a statistically significant difference was observed between the two groups at the FPD bridge (p value = 0.021 *), mandible (p value = 0.021 *), dentin (p value = 0.043 *), cementum (p value = 0.043 *), and PDL (p value = 0.043 *). Meanwhile, there was an insignificant increase in displacement values recorded in the distal implant (p value = 0.083). This study highlighted the importance of connector design in the overall stability and performance of the prosthesis. Notably, the 4.7 mm × 10 mm implant in Group B showed a displacement nearly 92 times higher than its rigid counterpart in Group A. Overall, the 5.7 mm × 10 mm combination of implant length and diameter showcased the best performance in both groups. The findings demonstrate that wider implants with a proportional length offer greater resistance to displacement forces. In addition, the use of rigid connection design provides superior biomechanical performance in tooth-implant fixed partial dentures and reduces the risk of micromotion with its associated complications such as ligament overstretching and implant overload, achieving predictable prognosis and enhancing the stability of the protheses. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the significance of the connector type on stress dissemination within the tooth‐implant‐supported fixed dental prostheses in the mandibular posterior region with different combinations of implant diameter and length by means of finite element analysis (FEA). Materials and Methods: Six models of different designs for tooth‐implant fixed dental prosthesis (FDPs) were simulated and divided into two main groups. Implant lengths were 10, 11.5, and 13 mm while implant diameters were 3.7, 4.7, and 5.7 mm. The main difference between the groups was the connector type. Models were evaluated using 3D FEA (Solidworks Premium 2018 × 64 Edition). Group A tooth‐implant FDPs (5.7 mm × 10 mm) had a mesial and distal rigid connector while group B tooth‐implant FDPs (3.7 mm × 10 mm, 3.7 mm × 11.5 mm, 3.7 mm × 13 mm, 4.7 mm × 10 mm and 5.7 mm × 10 mm) had a mesial non‐rigid connector in their design between the pontic and the tooth. Models were analyzed to determine the magnitude of von Misses Stresses at six specific zones (fixed dental prosthesis, bone around distal implant, bone around tooth, cementum, periodontal ligament, implant) under vertical occlusal loading of 100 N after meshing and assigning the material properties. Results: Stress values around the supporting bone were significantly higher in Group B (tooth‐implant FDP with non‐rigid connection) when compared to Group A (tooth‐implant FDP with rigid connection). Also, the stresses measured at the FDP level showed that the rigid connection group (5.7 mm × 10 mm) exhibited 26% lower stress values when compared to the non‐rigid group (5.7 mm × 10 mm). Conclusions: Implant‐tooth FDPs with rigid connector design using the combination of implant diameter and length (5.7 mm × 10 mm) demonstrated a better design modality thus predicting a higher success rate and more longevity than using the non‐rigid connection option. [ABSTRACT FROM AUTHOR]

The aim of this study is to evaluate the effectiveness of the implant diameter and length on force dissemination of tooth-implant and implant retained fixed restorations. A finite analysis model was used via a 3D simulation of a unilateral mandibular Kennedy Class I arch. Through thresholding the resultant assembly, a region of interest was selected from the computed tomography (CT) scan. Details of the diameter (D) and length (L) of implant were introduced. Ds used were 3.7, 4.7, and 5.7, while Ls used were 10, 11.5, and 13. The constant was the use of rigid connectors in both designs (implant-implant and implant-tooth fixed partial dentures [FPDs]) and the mesial implant (D 3.7 and L 11.5). Stress in cancellous bone around mesial abutment, which is the second premolar in tooth-implant FPD and mesial implant in the implant-implant FPD, revealed that the stress was significantly lower in tooth-implant FPD when compared with implant-implant FPD (21.1 ± 0.00 vs 46.1 ± 0.00, P <.001). Stress distribution in the bone around any implant depends on several factors such as diameter, length, and tooth-implant vs implant-implant support. The implant diameter was more significant for improved stress distribution than implant length. A moderate increase in the length of the implant consequently reduced stress. [ABSTRACT FROM AUTHOR]

Purpose/Objectives: Empathetic communication of dentists with their patients is a primary characteristic of their health care. This study aims to evaluate dental students' empathy levels during the transitional period of internship and postgraduate studies of different specialties at one of the oldest dental schools in Saudi Arabia and explore how this empathy was affected by gender, age, and study duration. Methods: In this study, the self‐reported empathy level among the participants was assessed using the Jefferson scale of empathy‐student version (JSE‐HPS). This survey includes a 20‐question Likert scale formulated to measure clinical empathy in health care professionals. The JSE‐HPS was distributed to all registered dental interns and postgraduate students during the academic year 2019–20 in King Abdulaziz University Faculty of Dentistry (KAUFD), Jeddah, Saudi Arabia. Results: Mean total score of empathy of the participants was (101.07 ± 14.8) with a response rate of 89%. A statistically significant higher empathy score appeared among dental postgraduate students in general (p = 0.04) and specifically among the females (p = 0.04) and those with postgraduate programs for more than four years, (p = 0.02). Dental postgraduate students scored significantly higher in the parameters of standing in patients' shoes (p = 0.02). Conclusion: Gender, academic level, and duration of postgraduates' studies influenced empathy more than the age of the dental graduates in KAUFD. Our recommendation is to integrate empathy into the dental curriculum emphasizing interactive communication skills and early patient contact. [ABSTRACT FROM AUTHOR]

MgO nanoparticles have been recently discovered as an antibacterial, however, they limited by property degradation due to agglomeration. The addition of a coating agent, such as a zein polymer, is effective in preventing agglomeration without affecting nanosized properties. The aim of this study was to assess the antimicrobial property of MgO nanoparticles when coated with a zein polymer against several oral bacteria and fungi. This was done by utilizing various assessment techniques. The ultimate aim is to use these nanoparticles in dental preparations. The antimicrobial activity of zein-coated MgO nanoparticles at different concentrations of 0.5, 1 and 2% were tested against four different microorganisms: Staphylococcus aureus, Streptococcus mutans and Enterococcus faecalis (gram positive bacteria), and Candida albicans (as oral fungus). Two different techniques were utilized: the Kirby-Bauer test, and a modified direct contact test. The results indicated that the antibacterial effect of 1% or 2% zein-coated MgO nanowires were statistically significant (p<0.05) against the four organisms studied: S. mutans, S. aureus, E. faecalis and C. albicans. Zein-coated MgO nanoparticles are a new human friendly and potent antimicrobial agent that can be incorporated in the formulation of a variety of new dental materials and products that should provide improvements in dental care and oral health. [ABSTRACT FROM AUTHOR]

Patient satisfaction levels in any health institute are a key performance indicator of quality health care. We constructed a 36-item questionnaire and distributed it over a three-month period (from February to April 2014) to 301 patients treated in various departmental clinics at King Abdulaziz University Dental Hospital. The survey addressed satisfaction with facilities, helpfulness of the staff, progress of treatment, quality of care and treatment with dignity and compassion. Patients were overall satisfied with the treatment received (84.1%), with particular satisfaction for doctors and faculty supervisors being courteous (73.4%, and 61.0%, respectively), and addressing their concern (54.3% and 60.0%, respectively). Dissatisfaction was found with the patient relations’ attitude (48.2%) and professionalism (49.6%), and the majority of patients claimed to be very unsatisfied with the referral system (69.0%) and the difficulty in contacting the clinics (72.0%). The results of the present study revealed that King Abdulaziz University Dental Hospital provides quality dental services to its patients and there is an overall high rate of patient satisfaction for the treatment and services rendered by the institute. However there are still issues and some concerns such as patient relation communication skills and referral system professionalism that have to be addressed in order to improve the patient experience. [ABSTRACT FROM AUTHOR]

The problem of fracture of composite resin under flexure and shear loads has regularly been encountered. Few studies claimed that the addition of fiber improves the mechanical properties of dental composite. The aim of this study was to evaluate the effect of the addition of polyethylene fiber to hybrid composite on the following properties; water sorption, compressive strength, flexural strength, shear bond strength to enamel, and shear bond strength to dentin. A total number of 100 specimens were used to conduct this study. The results were collected, tabulated and statistically analyzed using ANOVA and “student’s” t test. It was found that the addition of polyethylene fiber resulted in a significant increase in the water sorption and in the flexure strength properties of hybrid composite (p < 0.05). It was concluded that the addition of polyethylene fiber does not significantly improve the properties of hybrid composite, and further studies are required to evaluate the effectiveness of adding fiber to hybrid composite. [ABSTRACT FROM AUTHOR]

The aim of this study was to test the antimicrobial properties of dental cements modified with magnesium oxide (MgO) nanoparticles. Zein-modified MgO nanoparticles (zMgO) in concentrations (0.0, 0.3, 0.5, and 1.0%) were mixed with dental cements (Fuji II, Rely X Temp E, Ionoglass Cem, Es Temp NE, and System P link). Eight discs were fabricated from each zMgO-cement pair for a total of 32 specimens for each cement. Characterization of the dental cements incorporating zMgO was done by X-ray Diffraction (XRD) and Field Emission Scanning Electron Microscopy (FESEM). The antimicrobial properties of the mixtures were tested using direct contact and agar diffusion assays against Streptococcus mutans, Staphylococcus aureus, Enterococcus faecalis , and Candida albicans . Data was analyzed using two-way analysis of variance and LSD post hoc test at 0.05 significance level. XRD spectra showed sharp peaks of zMgO indicating its high crystalline nature, while the amorphous dental cements with zMgO had broad peaks. FESEM analysis showed a uniform distribution of the zMgO nanoparticles in the cement. There were significant inhibition zone values associated with all concentrations of zMgO-cement mixtures tested compared to controls ( p < 0.001) with a dose-response recorded only with Fuji II. Optical density values were significantly lower in zMgO groups compared to controls for all microorganisms. The effect was most prominent with Rely X against C. albicans and S. aureus . Dental cements containing zMgO showed significant antimicrobial properties that were dependent on the specific initial cement substrate., (© 2021 The Authors.)