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Dental simulation head model laboratories are crucial for clinical simulation training for stomatological students, yet the maintenance of their dental unit waterlines (DUWLs) has been overlooked. This study investigated water contamination in DUWLs within these laboratories and proposed solutions. Water samples were collected from 12 dental chairs in three laboratories at three time points: the beginning, middle, and end of the semester. At the start of the semester, severe contamination was observed, with colony counts of 11,586 1715 CFU/ml for high-speed handpieces and 5375 874 CFU/ml for three ways syringes. As the semester progressed, colony counts gradually decreased but remained above clinical thresholds. Both 20 mg/L organochlorine disinfectant and 20 mg/L chlorine dioxide were effective in reducing bacterial contamination below standard ranges three days post-disinfection. Microbial diversity analysis revealed Proteobacteria and Bacteroidota as the dominant bacterial phyla, with Ascomycota as the dominant fungal phylum. Potentially pathogenic bacteria such as Pseudomonas, Burkholderia-Caballeronia-Paraburkholderia, Ralstonia, Mycobacterium, Legionella, Paenibacillus, Streptomyces, Acinetobacter, and Prevotella, as well as fungi like Fusarium and Penicillium, were detected. Therefore, urgent attention is needed to address DUWL contamination in dental laboratories, and it is recommended to disinfect DUWLs using either 20 mg/L organochlorine disinfectant or 20 mg/L chlorine dioxide every three days. [ABSTRACT FROM AUTHOR]

Copyright of Quintessenz der Zahntechnik is the property of Quintessenz Verlags GmbH and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Quintessenz der Zahntechnik is the property of Quintessenz Verlags GmbH and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Quintessenz der Zahntechnik is the property of Quintessenz Verlags GmbH and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Quintessenz der Zahntechnik is the property of Quintessenz Verlags GmbH and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: The existing literature predominantly examines post and core assessments post-cementation, neglecting the critical pre-cementation phase. Research on the clinical acceptance of dental posts received from dental laboratories before cementation is notably lacking. This study investigates the percentage of zirconia and metal dental posts that are deemed suitable for cementation by clinicians, among the total received from the dental laboratory. Additionally, it aims to examine whether this percentage varies based on the type of impression made by the clinician: digital impression versus conventional impression. Methods: This article introduces the application of computer-aided design-computer-aided manufacturing (CAD-CAM) technology for manufacturing customized zirconia and Cobalt–Chromium (Co-Cr) post and cores. Intraoral scanning is employed to capture the canal anatomy. In contrast to the traditional casting process, a three-dimensional (3D) metal printer machine is utilized to 3D print the metal post and core from Co-Cr, resulting in enhanced toughness and superior adaptability to the canal. Two null hypotheses were formulated, investigating the clinical acceptance of zirconia and metal posts obtained through traditional versus digital impressions. Results: Among 577 post and cores, 95% of metal posts from both impression methods received clinical approval. However, for zirconia posts, a significantly higher acceptance rate (95% versus 88%) was observed for those from traditional impressions. The Chi-squared test yielded a p-value < 0.05, underscoring the clinical superiority of conventionally obtained zirconia posts and supporting the null hypothesis for metal posts. Conclusions: A significantly higher acceptance rate is apparent among zirconia post and cores manufactured through conventional impressions, in contrast to zirconia post and cores produced via digital impressions. No statistically significant difference was identified between metal post and cores obtained through digital impressions and those acquired through conventional impressions. [ABSTRACT FROM AUTHOR]

Background and Aims: Ensuring the long-term stability of orthodontic treatments and preventing tooth relapse remains a significant challenge in orthodontics, often addressed through the extended use of retainers. Given the pivotal role of retainers' physical and mechanical properties in this regard, this study aimed to investigate the tensile strength, flexural strength, and deflection of three distinct types of fixed orthodontic retainers. Materials and Methods: In this laboratory study, each group comprised 12 samples of twisted, flat, and coaxial retainer wires, each measuring 8 mm in length. These samples were affixed onto the polyethylene blocks using cyanoacrylate adhesive and subsequently subjected to compressive loads using a universal testing machine. The maximum bending strength and deflection rate were recorded from stress-strain diagrams. To evaluate the tensile strength, the identical samples underwent tensile loading. Statistical analysis was performed utilizing SPSS software, employing analysis of variance tests to compare data between groups. Results: Significant differences were observed in the bending strength (P=0.004), deflection (P<0.001), and tensile strength (P<0.001) among the investigated retainer wires. The flat retainer wire exhibited the highest bending strength, averaging 822.876±136.07 MPa, while the coaxial retainer wire showed the lowest, with an average of 673.65±73.35 MPa. Regarding deflection, the flat retainer wire displayed the highest average at 4.04±0.6 mm, surpassing the other two types of retainers. However, the tensile strength of the twisted retainer wires, averaging 699.7±83.46 MPa, exceeded that of both the flat and coaxial retainer wires. Conclusion: The flat retainer wires demonstrated the highest bending and deflection strength, while the twisted retainer wires exhibited the highest tensile strength. Overall, the bending strength, deflection, and tensile strength of the 3-strand twisted and flat retainer wires outperformed those of the 5-strand coaxial retainer wires, increased flexural and tensile strengths imply a higher resistance of the wires to the forces induced by harder and more viscous foodstuffs. [ABSTRACT FROM AUTHOR]

Farid Tawfiq Nusairat,1 Salam Walid Al-Shogran,1 Noor Almortadi,2 Karem H Alzoubi3,4 1Department of Health Policy and Management, Faculty of Medicine, Jordan University of Science and Technology, Irbid, Jordan; 2Department of Applied Dental Sciences, Faculty of Applied Medical Sciences, Jordan University of Science and Technology, Irbid, Jordan; 3Department of Pharmacy Practice and Pharmacotherapeutics, College of Pharmacy University of Sharjah, Sharjah, United Arab Emirates; 4Department of Clinical Pharmacy, Faculty of Pharmacy, Jordan University of Science and Technology, Irbid, JordanCorrespondence: Farid Tawfiq Nusairat, Email ftnusairat@just.edu.joBackground: Despite the great effort between the dentist and dental technician in prosthesis fabrication, there is a lack of proper communication. According to the laboratory prescription, the communication process must include all the essential elements to complete the prosthesis fabrication correctly. The digital revolution in dentistry suggested using information technology system prescriptions instead of traditional prescriptions.Aim: To explore the association between the application of ITS and the communication process between dental laboratories and dental clinics in a developing country setting.Methods: The current study used a quasi-experimental design (posttest only). A convenience sample of 600 subjects was divided into two subsamples of 300 subjects each. The data from the first subsample was collected from traditional (paper-based) prescriptions, and the data from the second subsample was collected from the Information Technology System (ITS).Results: It was associated with a statistically significant commitment to recording the most essential information in the dental lab prescription. The time spent completing and delivering the work was faster, and the need for recommunication was less common among those using ITS than those using traditional systems. Regarding the quality of the prosthesis, the need for modification or redo due to improper shade, inappropriate charting of teeth, or lack of additional information in the dental lab prescription was less among users of the ITS system compared to the traditional system (P < 0.05).Conclusion: Using ITS instead of a traditional system can enhance the communication process and the amount filled in the laboratory prescription in multiple aspects, including the completeness of essential information in the dental lab prescription, the time needed to complete the cases, the need to re-communicate less frequently with the dentist, and improved the quality of the prosthesis.Keywords: information technology system, communication process, dental laboratories, dental clinics

In the dental prosthetics field, BLDC micro-motors are primarily used for implant procedures. As dental materials become increasingly harder, there is a growing demand for higher performance motors to precisely process these materials. However, difficulties in motor development arise due to price competitiveness. Dental motors require capabilities such as low-speed, high-torque for drilling operations and high-speed rotation for precise machining of high-strength dental materials. Additionally, there is a requirement to address thermal issues to prevent user burns due to motor-generated heat. Typically, motors requiring precision control utilize high-resolution position sensors like encoders or resolvers to acquire and control the rotor's position. However, the high cost of these sensors and constraints such as increased device size pose challenges in maintaining price competitiveness. In this paper, we propose a control algorithm that satisfies the requirements for low-speed, high-torque and high-speed operation requirements for precision machining without hardware modifications using a BLDC micro-motor equipped with an inexpensive Hall sensor commonly used in the dental field. Furthermore, the algorithm is designed to ensure stable operation even in the event of Hall sensor failure or malfunction, and its effectiveness is validated through experiments. [ABSTRACT FROM AUTHOR]

Aims: The aim of this study is to identify methods for the digital analysis of the closest speaking space in dentates and to assess certain particularities using digital analysis. Method: For the adult patients included in this study, traditional dental casts were fabricated, and interocclusal registrations of the maximal intercuspal position and of the closest speaking space were taken using polyvinyl siloxane. Dental casts in both positions were scanned using a dental laboratory scanner, and digital analysis was conducted using the 3Shape 3D Viewer. Results: The interocclusal distance corresponding to the closest speaking space can be easily and precisely measured digitally or assessed using occlusion maps, at the level of all teeth. The interocclusal distance was variable across the dental arch, central incisors, and second molars, registering the smallest values, and was asymmetrical, with mandibular lateral deviation being suggested. The assessment of the range of motion of the mandible during the speaking test, recorded based on tooth movement, was conducted using superimpositions. The movement of the tooth was the largest in central incisors and decreased progressively as the tooth was more distal, and, in all cases, mandibular deviation occurred, more frequently to the left. Conclusions: Digital methods for the analysis of the closest speaking space have the advantages of increased precision and a broader range of analysis and application, showing research and clinical value. [ABSTRACT FROM AUTHOR]

Background. The procedures of dental implant application can lead to optimal clinical outcomes, being simplified by the guided implantology protocol. In the latest articles from specialized literature it is said that digital planning of implants ensures the most accurate diagnosis of the area where the implant will be positioned, with clinical benefits including reduced operative time and a lower rate of complications, all of which can ultimately lead to better acceptance and greater patient satisfaction. Case report. A 55-years-old female patient came to the clinic for a full mandibula rehabilitation. In this situation, the patient wanted a solution using only fixed restoration so the treatment plan that the patient agreed to was an all-on-X restoration. Aim. Given the constant evolution of technology, along with the development of dental technical laboratories, this paper wants to prove that the latest technology can help doctors in placing the dental implants accurately and in a more comfortable manner for both the patient and the doctor. Material and methods. For this case, the insertion of dental implants was performed using the static approach, which refers to the use of tissue-supported surgical guides; this replicates the virtual position of the implant directly from the data provided by Cone Beam Computed Tomography (CBCT). This information was converted into a surgical guide that was used during the surgical procedure. Before the surgical intervention, a CBCT scan was performed, which was used along with the patient's intraoral scanning to establish the ideal position of each dental implant. After the surgical intervention and after the complete healing, another CBCT scan was conducted. Thus, to analyze the accuracy of dental implant insertion, radiological investigations were compared to see the differences between the ideal situation planned before the surgery and the situation resulting from the surgery. Results. The results demonstrate a high degree of accuracy in the insertion of dental implants using the three-dimensional surgical guide, without significant positioning differences. Conclusions. These outcomes support the main purpose of three-dimensional surgical guides, namely the conservation of anatomical structures at the level of the dento-maxillary system. [ABSTRACT FROM AUTHOR]

Copyright of Quintessenz der Zahntechnik is the property of Quintessenz Verlags GmbH and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Quintessenz der Zahntechnik is the property of Quintessenz Verlags GmbH and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: To evaluate the mechanical performance of patient‐specific prefabricated temporary shell versus laboratory‐fabricated CAD/CAM provisional restorations on titanium temporary abutments, with and without thermo‐mechanical ageing. Materials and Methods: Implants with a conical connection were divided into four groups (n = 24) and restored with temporary shell or laboratory‐fabricated central or lateral incisor PMMA restorations that were relined or bonded on titanium temporary abutments. The diameter of the central and lateral incisor groups' implants was regular (ϕ 4.3 mm) or narrow (ϕ 3.5 mm), respectively. Half of each group's specimens were subjected to ageing, simultaneous thermocycling (5–55°C) and chewing simulation (120,000 cycles, 50 N, 1.7 Hz) resulting in eight groups in total (n = 12). The aged specimens were evaluated with optical microscopy, and survival and complication rates were determined according to modified USPHS criteria. The non‐aged specimens and those that had survived ageing were loaded until failure, whereupon bending moments were calculated. Results: Survival rates after ageing were 100% for all groups. Apart from wear facets (ϕ 2–3 mm) on the palatal restoration surface, no complications were observed. The mean fracture load and bending moments ranged between 597.6–847.1 N and 433.3–550.6 Ncm, respectively, with no significant differences between the eight groups (p =.25; p =.20). Conclusions: As patient‐specific temporary shell central and lateral incisor provisional implant‐supported restorations are mechanically stable enough to withstand clinical bite forces, even after thermo‐mechanical ageing, they may serve as an alternative to laboratory‐fabricated provisional restorations. [ABSTRACT FROM AUTHOR]

Transferring the intraoral situation accurately to the dental laboratory is crucial for fabricating precise restorations. This study aimed to compare the dimensional accuracy of a new hydrophilic quadrofunctional vinyl polysiloxane (VPS) and polyether (PE), in combination with different impression techniques (mono-phase single step or dual-phase single step). The reference model simulated a partially edentulous mandible. Stainless-steel precision balls were welded to specific teeth and were used to detect dimensional deviations. Fifteen impressions were made for each of the following four test groups: (1) VPS mono-phase, (2) PE mono-phase, (3) VPS dual-phase, and (4) PE dual-phase. Global accuracy was measured by deviations from the reference model, while local accuracy focused on the trueness and precision of abutment tooth surfaces. Statistical analysis was conducted using ANOVA (α = 0.05). All distances were underestimated, with the highest global inaccuracies for the cross-arch distance, ranging from −82 µm to −109 µm. The abutment tooth surfaces showed excellent local accuracy for all the materials and techniques, with crown surface trueness < 10 µm and precision < 12 µm. Inlay surfaces had higher inaccuracies (trueness < 15 µm, precision < 26 µm). Within the limitations of this study, all impression materials and techniques can be used to produce models with clinically acceptable accuracy. [ABSTRACT FROM AUTHOR]

Effective communication between clinicians and the dental laboratory is paramount in the realm of dental implant restorations, where precision and meticulous planning are key for success. This article explores the transformative shift towards digital workflows, highlighting the collaborative dance between the clinician and the dental laboratory. The power of visual communication is emphasised, with examples illustrating its impact on the precision of treatment plans. Celebrating these digital tools, this article envisions a new era of collaboration, transcending traditional communication methods for more predictable and successful implant restorations. [ABSTRACT FROM AUTHOR]

Copyright of Quintessenz der Zahntechnik is the property of Quintessenz Verlags GmbH and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: The aim of this study was to assess the feasibility of digitally scanning dentures and 3D printing replica dentures for care home residents. The study also investigated whether the process and replacement denture was acceptable to the resident. Background: Denture loss is a significant issue for people living in care homes and impacts on nutrition, quality of life and dignity. Denture loss is underreported, and care home residents have barriers to accessing dental care. The conventional process for remaking a denture can often take approximately 2 months with multiple clinical stages, often not feasible in adults with frailty and cognitive impairment. Scanning and 3D (3 dimensional) printing are increasingly used in dentistry, this rapidly evolving technology may provide an innovative solution to denture loss. Materials and Methods: A digital workflow was established using a handheld scanner and 3D printing technology. Care home residents wearing functional acrylic dentures were recruited. Dentures were scanned within the care home, and the scan was sent to a dental laboratory for 3D printing. The dentures were fitted at a subsequent visit, and semi‐structured interviews were undertaken with the resident. Using thematic analysis, the feasibility of this pathway was assessed, and the use of digital scanning technology was explored. Results: Eight residents successfully had dentures scanned and replicated to a satisfactory standard. It took, on average, 10 minutes to scan a denture and 20 minutes to print the denture. All replica dentures were satisfactory to the resident. Qualitative data from semi‐structured interviews showed that study participants were satisfied with denture replacements and the process. The 3 main themes that emerged were: the significance of dentures to the individual, satisfaction with the scanning process and general low self‐esteem and fatigue. Conclusions: This study has established a workflow for digitally storing dentures and replicating them satisfactorily. In the context of a care home setting, a scan of a denture can be used to provide a replacement denture if lost or broken. A large‐scale study could follow now that the feasibility of this pathway has been demonstrated. [ABSTRACT FROM AUTHOR]

In this study, we introduce a new approach to path planning suitable for both static and dynamic environments. Our method combines the Obstacle Avoidance Improved A* (OA-IA*) algorithm with the Time Elastic Band (TEB) technique. The OA-IA* incorporates four key elements: utilization of robot direction information, adaptive adjustment of bandwidth, enhancement of evaluation function, and path smoothing operations. We conducted experiments to validate our approach, including simulations and real-world verifications in various environments. In the simulation experiments, we compared our method with two previous approaches: Improved Local Particle Swarm Optimization (ILPSO) and Obstacle Avoidance RRT (OA-RRT) method. Across seven different simulated maps, the OA-IA* algorithm showed an average improvement of 0.19 in Path Optimal Degree (POD) compared to the ILPSO algorithm, along with an average time savings of 11 s. Furthermore, compared to the OA-RRT algorithm, the OA-IA* algorithm achieved an average POD increase of 0.36, resulting in an average time savings of 60.37 s. Moreover, we compared our method with APF-RRT*, APF-RRT, RRT, and RRT* approaches across 50 simulation maps. On average, our method achieved higher POD values by 0.54, 0.31, 0.85, and 0.26 compared to APF-RRT*, APF-RRT, RRT, and RRT* methods, respectively. Additionally, the average running time of our method was significantly reduced by 90 s, 64.7 s, 38.13 s, and 19.4 s compared to APF-RRT*, APF-RRT, RRT, and RRT* methods, respectively. In the experimental verification section, we tested our method in a real office, laboratory, and workshop environments. In two real-world environments spanning 9.4 m 2 and 9.2 m 2 , our enhanced A* method integrated with TEB exhibited an average POD value that at least 0.125 higher compared to that of ILPSO combined with TEB. These results demonstrate the effectiveness of our hybrid path planning method in complex dynamic environments, achieving optimal outcomes in terms of path length, smoothness, and speed. In addition, it also ensures the smoothness of the path and speed, and the smoothness is less than 0.05 rad/s 2 . [ABSTRACT FROM AUTHOR]

Background: The reported outcomes of pediatric dilated cardiomyopathy (DCM) have varied across studies. There are few outcome data concerning DCM in Chinese children. Therefore, we conducted a retrospective study to describe clinical features and determine risk factors for poor outcomes in children with DCM. Methods: We enrolled 121 children with DCM in our hospital from 2003 to 2021. General information and laboratory and echocardiographic data were collected and analyzed. Cox regression analysis was performed to determine risk factors for poor outcomes. Results: This study included 121 patients (69 males and 52 females). The median age at diagnosis was 10.8 years, and the follow-up time was 10.0 months. Eighty-two patients (67.8%) exhibited cardiac function classes III–IV at the time of diagnosis. Tachypnea was the most common symptom (78.5%). In echocardiography, the mean left ventricular end-diastolic dimension z score was 7.36 ± 2.73, and the left ventricular ejection fraction z score was −6.58 ± 2.17. The 1-, 2-, and 5-year survival rates were 51.2%, 43.8%, and 32.2%, respectively. Cox analysis revealed that cardiac function classes III–IV (hazard ratio [HR] = 1.801, 95% confidence interval [95% CI] = 1.030–3.149, p = 0.039) and calcium levels (HR = 0.219, 95% CI = 0.084–0.576, p = 0.002) were predictors of poor outcomes in children with DCM. Conclusions: Children with DCM are at high risk of death. Cardiac function class III–IV and calcium levels were related to the prognosis of pediatric DCM patients. [ABSTRACT FROM AUTHOR]

The aims of this study were to investigate the relationship between self-reported preventive and curative orientations of general dental practitioners (GDPs) and the oral healthcare services (OHS) they provided to patients under 18-years-old. And in addition, to determine which patient, GDP, and dental practice characteristics predicted the provision of preventive and curative care. GDPs in the Netherlands using dental software program Exquise (>2,000) were invited to participate in this study voluntarily. Participants completed a web-based questionnaire on characteristics of themselves, their dental practices, and on 20 hypothetical clinical situations concerning caries management. Based on their responses GDPS were classified for their preventive orientation, and their curative orientation. Data on the OHS provided to their young patients over the period 2013–2017 were automatically extracted from the patient files. Based on the annual frequency of provided care to regular patients over a period of 4 or 5 years, this was converted into 3 longitudinal care patterns regarding prevention and 3 longitudinal care patterns regarding curative care. Multinomial logistic regression analyses were conducted with a multilevel approach to correct for dental practices. The 37 participating GDPs provided data for 16,229 young patients. There was not a significant relationship between self-reported preventive orientations and preventive care patterns. The self-reported middle curative orientation was a predictor of the care pattern 'curative treatment(s) in 1 year' (OR 1.23 compared to nu curative treatments; 95% CI 1.02–1.48). The self-reported high curative orientation was a predictor of 'curative treatments in several years' (OR 1.90; 95% CI 1.27–2.85). Common characteristics predicting (p<0.05) both regular preventive care and curative treatments in several years were patient related: age 4–9 and 10–12, low-income neighborhood, 5 years included in study. GDP and dental practice related predictors were: the GDP could fulfill the care demand by working overtime, small dental practice (≤2,000 patients), and practice policy on the provision of care to young patients. This showed that the variation in provided care was partly supplier-driven instead of patient-centered. [ABSTRACT FROM AUTHOR]

Recently, due to the high demand for dental implants, the use of dental implant stock abutments has increased significantly, especially dental custom CAD/CAM implant abutments milled by dental technicians in their laboratories. The purpose of this study is to analyze the surface quality of the emergence profile of dental custom CAD/CAM implant abutments made by a non-industrial milling machine, compared to original and compatible dental implant stock abutments made by industrial machines. Thirty dental implant abutments were divided into six study lots. Lot 1 (control group): original dental implant stock abutments—industrial machined; lot 2 (study group): compatible dental implant stock abutments—industrial machined; lots 3, 4, 5, and 6 (study groups): compatible custom CAD/CAM dental implant abutments—non-industrial milled with hyperDENT CAM software and Paragon Tools. The Nikon SMZ745T stereomicroscope was used to analyze the emergence profile surface of each dental implant abutment. The structure of the analyzed surfaces did not show significant differences between original and compatible abutments that were industrially machined. As for the customized dental implant abutments, the greatest similarity with the original was obtained for lot 6, and a significant statistical difference was obtained for lot 4. Stepover and Feed Rate parameters of the milling process influenced the surface roughness of the emergence profile for the customized dental implant abutments. The digital technology of non-industrial milling compatible custom CAD/CAM dental implant abutments is reliable and within the correct milling parameters. [ABSTRACT FROM AUTHOR]

This study investigated the usefulness of a dental laboratory polymerization unit with light-emitting diode (LED) as a light source. The depth of cure (n=15), water absorption and solubility (n=9) of two indirect composite materials (Cesead N and Solidex Hardura) were evaluated by five dental laboratory polymerization units (LED Cure Master, Twinkle LED, α-Light V, α-Light II, and Hyper LII). Statistical analysis was performed by one-way ANOVA and Tukey test or non-parametric tests. Comparison of light sources for curing depth showed that metal halide had the highest value, followed by the LED group with similar values, and halogen lamps with the lowest value. The water absorption and solubility of the composite specimens polymerized with the three LED laboratory polymerization units were within the ISO recommended limit. [ABSTRACT FROM AUTHOR]

Copyright of International Journal of Computerized Dentistry is the property of Quintessence Publishing Company Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Quintessenz der Zahntechnik is the property of Quintessenz Verlags GmbH and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Quintessenz der Zahntechnik is the property of Quintessenz Verlags GmbH and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Quintessenz der Zahntechnik is the property of Quintessenz Verlags GmbH and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Nowadays, digital technologies represent an essential tool for dentists and dental technicians, and the backbone of the communication between them. Aim of the study is to analyze the application of digital technologies in a common dental office and in transferring information to the dental lab. Materials and methods. The retrospective study included patients who presented for treatment to the dentist, in a 12 months period of time. Searched databases included dental charts, radiologic and imagistic data (OPG, CBCT), clinical photos and digital dental impressions. A comparison was made between the used digital tools as frequency. Results: 580 patients were included, 275 men and 305 women, aged between 19 and 82. Digital technologies used in the dental office in the studied period were: OPG (100%), CBCT examinations (25,34%), digital photographic exams (38,10%), intraoral scanning (24,13%), digital intraoral impressions (19,65%). Conclusions: All patients who attended the dental office during the study period received an OPG examination, while significant fewer patients were investigated using other digital technologies. For an easier, faster and complete data transfer between dental office and dental lab, digital evaluation is mandatory. [ABSTRACT FROM AUTHOR]

Copyright of Quintessenz der Zahntechnik is the property of Quintessenz Verlags GmbH and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Quintessenz der Zahntechnik is the property of Quintessenz Verlags GmbH and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Quintessenz der Zahntechnik is the property of Quintessenz Verlags GmbH and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose: The aim of this study was to evaluate image artifacts in the vicinity of dental implants in cone-beam computed tomography (CBCT) scans obtained with different spatial orientations, tube current levels, and metal artifact reduction algorithm (MAR) conditions. Materials and Methods: One dental implant and 2 tubes filled with a radiopaque solution were placed in the posterior region of a mandible using a surgical guide to ensure parallel alignment. CBCT scans were acquired with the mandible in 2 spatial orientations in relation to the X-ray projection plane (standard and modified) at 3 tube current levels: 5, 8, and 11 mA. CBCT scans were repeated without the implant and were reconstructed with and without MAR. The mean voxel and noise values of each tube were obtained and compared using multi-way analysis of variance and the Tukey test(α=0.05). Results: Mean voxel values were significantly higher and noise values were significantly lower in the modified orientation than in the standard orientation (P<0.05). MAR activation and tube current levels did not show significant differences in most cases of the modified spatial orientation and in the absence of the dental implant (P>0.05). Conclusion: Modifying the spatial orientation of the head increased brightness and reduced spatial orientation noise in adjacent regions of a dental implant, with no influence from the tube current level and MAR. [ABSTRACT FROM AUTHOR]

This study aimed to assess dental technologists/technicians knowledge, attitudes, and practice during the COVID-19 pandemic in Saudi Arabia. This cross-sectional study was conducted among workers in dental laboratories in Saudi Arabia. A validated questionnaire was developed based on previous literature and distributed online. The questionnaire assessed the study population’s knowledge, attitude, and practice regarding infection control protocol for COVID-19. Descriptive statistics of categorical variables were conducted. The response rate was 58.3%, where most respondents are male at a rate of 97%. Most of the participants (82%) were aware of the various infection control measures for COVID-19 in a dental laboratory. Forty-eight participants showed a level of knowledge range between 80 and 100%, while 27 and 30 participants reported moderate and low level of knowledge, respectively. Only 67% of the participants strongly agree that dental cast and fabricated/repaired restorations should be transferred in a very close and protective package to control infection. About 70% of participants indicated they always wear protective gear/goggles and should be warned while working in the dental laboratory. As the pumice slurry was utilized frequently to clean and polish the prostheses, 66% of participants agreed that pumice slurry should be always changed regularly. Regarding COVID-19 infection control procedures, dental technologists/technicians showed good knowledge, attitude, and practice; however, considering how infectious the virus is, more measures should be taken into consideration. Effective communication and collaboration between the laboratory and the dental clinic are essential for infection control.

Copyright of Quintessenz der Zahntechnik is the property of Quintessenz Verlags GmbH and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article reviews the book "Practical Applications in Dental Occlusion – Analog to Digital" by Michael Radu, which focuses on therapeutic jaw relations. Radu shares his clinical experience and beliefs on jaw relations, emphasizing the importance of clear concepts for determining jaw relations in various clinical situations. The book lacks emphasis on scientific aspects and neurobiological foundations, but provides practical guidance for dental practitioners and laboratories. It encourages both experienced and inexperienced readers to critically evaluate the recommendations against current guidelines. [Extracted from the article]

Background: Periodontal diseases may benefit more from topical treatments with nanoparticles rather than systemic treatments due to advantages such as higher stability and controlled release profile. This study investigated the preparation and characterization of thermosensitive gel formulations containing clindamycin-loaded niosomes and solid lipid nanoparticles (SLNs) loaded with fluconazole (FLZ), as well as their in vitro antibacterial and antifungal effects in the treatment of common microorganisms that cause periodontal diseases. Methods: This study loaded niosomes and SLNs with clindamycin and FLZ, respectively, and assessed their loading efficiency, particle size, and zeta potential. The particles were characterized using a variety of methods such as differential scanning calorimetry (DSC), dynamic light scattering (DLS), and Transmission Electron Microscopy (TEM). Thermosensitive gels were formulated by combining these particles and their viscosity, gelation temperature, in-vitro release profile, as well as antibacterial and antifungal effects were evaluated. Results: Both types of these nanoparticles were found to be spherical (TEM) with a mean particle size of 243.03 nm in niosomes and 171.97 nm in SLNs (DLS), and respective zeta potentials of -23.3 and -15. The loading rate was 98% in niosomes and 51% in SLNs. The release profiles of niosomal formulations were slower than those of the SLNs. Both formulations allowed the release of the drug by first-order kinetic. Additionally, the gel formulation presented a slower release of both drugs compared to niosomes and SLNs suspensions. Conclusion: Thermosensitive gels containing clindamycin-loaded niosomes and/or FLZ-SLNs were found to effectively fight the periodontitis-causing bacteria and fungi. [ABSTRACT FROM AUTHOR]

There is a vast amount of published literature concerning dental veneers; however, the effects of tooth preparation, aging, veneer type, and resin cement type on the failure of dental veneers in laboratory versus clinical scenarios are not clear. The purpose of the present narrative review was to determine the principal factors associated with failures of dental veneers in laboratory tests and to understand how these factors translate into clinical successes/failures. Articles were identified and screened by the lead author in January 2024 using the keywords "dental veneer", "complication", "survival rate", "failure", and "success rate" using PubMed/Medline, Scopus, Google Scholar, and Science Direct. The inclusion criteria included articles published between January 1999 and January 2024 on the topics of preparation of a tooth, aging processes of the resin cement and veneer, translucency, thickness, fabrication technique of the veneer; shade, and thickness of the resin cement. The exclusion criteria included articles that discussed marginal and internal fit, microhardness, water sorption, solubility, polishability, occlusal veneers, retention, surface treatments, and wear. The results of the present review indicated that dental veneers generally have a high survival rate (>90% for more than 10 years). The amount of preserved enamel layer plays a paramount role in the survival and success rates of veneers, and glass-ceramic veneers with minimal/no preparation showed the highest survival rates. Fracture was the primary failure mechanism associated with decreased survival rate, followed by debonding and color change. Fractures increased in the presence of parafunctional activities. Fewer endodontic complications were associated with veneer restorations. No difference was observed between the maxillary and mandibular teeth. Clinical significance: Fractures can be reduced by evaluation of occlusion immediately after cementation and through the use of high-strength veneer materials, resin cements with low moduli, and thin layers of highly polished veneers. Debonding failures can be reduced with minimal/no preparation, and immediate dentin sealing should be considered when dentin is exposed. Debonding can also be reduced by preventing contamination from blood, saliva, handpiece oil, or fluoride-containing polishing paste; through proper surface treatment (20 s of hydrofluoric acid etching for glass ceramic followed by silane for 60 s); and through use of light-cured polymerization for thin veneers. Long-term color stability may be maintained using resin cements with UDMA-based resin, glass ceramic materials, and light-cure polymerization with thin veneers. [ABSTRACT FROM AUTHOR]

Background: Dental casts made utilising digital workflow are becoming more common because to their speed and cost savings. However, studies on their dimensional accuracy over time with diverse designs are missing. Objective: The aim of this in vitro study was to assess the dimensional stability of 3D-printed edentulous and fully dentate hollowed maxillary models with 50-micrometer resolution over 1 day, 14 days, and 28 days using surface matching software. Methods: Scanned edentulous and fully dentate maxillary typodont models were used as references. The models were scanned by a desktop lab scanner of 15-micrometer accuracy (D900, 3Shape). Then, the files were used in designing software (Meshmixer, Autodesk) to create hollowed maxillary casts. Fifteen edentulous and 15 fully dentate (total of 30) models were printed using a DLP lab printer (Cara print 4.0, Kulzer). The 3D-printed models were scanned using the same desktop lab scanner of 15-micrometer accuracy at intervals of baseline days, 1 day, 14 days, and 28 days to assess the effect of aging (n = 120). The dimensional changes were quantified and compared using the root mean square (RMS) method, expressed in micrometres (µm). The study employed repeated measures analysis of variance (ANOVA) to assess and compare the root mean square (RMS) values across the variables. The data was analysed using SPSS (26, Chicago, Illinois, USA). Results: The RMS of the edentulous models rapidly increased from a mean value of 0.257 at the beginning of the study to 0.384 after twenty-eight days. However, the mean RMS values for the dentate models did not change much over the four intervals. It varied only from 0.355 to 0.347. The mean values for edentulous patients increased from 0.014 to 0.029 during the period from baseline to twenty-eight days. However, the mean average values decreased for the dentate models from 0.033 to 0.014 during this period. By utilizing ANOVA, mean RMS values increased insignificantly till one day but significantly to fourteen and twenty-eight days. Dentate model mean values differed insignificantly across four intervals. Repeated measures ANOVA for combined and separated data showed no significant differences across edentulous, dentate, and total models over times. Conclusion: The study revealed changes in the dimensions of 3D-printed edentulous models over a span of 3 and 4 weeks. Caution should be applied when using 3D-printed dental master models for constructing definitive prostheses on edentulous models over a period of 3 to 4 weeks. [ABSTRACT FROM AUTHOR]

Copyright of Quintessenz der Zahntechnik is the property of Quintessenz Verlags GmbH and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)