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Purpose: The purpose of this 3D finite element analysis was to evaluate the biomechanical effects of different materials used to fabricate occlusal devices to achieve stress distribution in simulated abutment screws, dental implants, and peri‐implant bone tissue in individuals who clench their teeth. Materials and Methods: Eight 3D models simulated a posterior maxillary bone block with three external hexagon implants (Ø4.0 × 7.0 mm) supporting a 3‐unit screw‐retained metal‐ceramic prosthesis with different crown connection (splinting), and the use of an occlusal device (OD). The OD was modeled to be 2‐mm thick. ANSYS 19.2 software was used to generate the finite‐element models in the pre‐and post‐processing phases. Simulated abutment screws and dental implants were evaluated by von Mises stress maps, and simulated bone was evaluated by maximum principal stress and microstrain maps by using a finite element software program. Results: The highest stress values in the dental implants and screws were observed in single crowns without OD (M1). Furthermore, the highest stress values and bone tissue strain were found in single crowns without OD (M1). The simulated material for the OD did not cause many discrepancies in terms of the stress magnitude in the simulated dental implant and abutment screw for both single and splinted crowns; however, more rigid materials exhibited lower stress values. Conclusion: The use of OD was effective in reducing stress in the simulated implants and abutment screws and stress and strain in the simulated bone tissue. The material used to simulate the OD influenced the biomechanical behavior of implant‐supported fixed prostheses, whereas splints with rigid materials such as PEEK and PMMA exhibited better biomechanical behavior. [ABSTRACT FROM AUTHOR]

Objective. To evaluate the influence of screw-tightening methods on the immediate and long-term stability of dental implant screw joints. Methodology. A total of 150 implants of three different implant systems with different diameters were used in this study. Each group was divided into three subgroups (n = 5), according to the tightening methods (A—tightening with recommended torque and retorque after 10 min; B—tightening with recommended torque, then loosening and immediate retorque; C—tightening with recommended torque only once). The operating time of tightening the assemblies was recorded. Ten minutes later, the immediate removal torque (IRT) (Ncm) was measured. After retightening the assemblies, a dynamic load between 20 and 200 N was applied for 105 cycles, and the postloading removal torque (PRT) (Ncm) was measured. Scanning electron microscopy (SEM) was used to observe the surface topography of the screws. Results. For different types of implants, the IRTs were 11.92 ± 1.04–34.12 ± 0.36 Ncm for method A, 11.64 ± 0.57–33.96 ± 0.29 Ncm for method B, and 10.30 ± 0.41–31.62 ± 0.52 Ncm for method C, and the IRTs of methods A and B were 6.28%–21.58% higher than that of method C (P ≤ 0.046). The PRTs were 4.08 ± 0.77–29.86 ± 0.65 Ncm for method A, 4.04 ± 0.40–29.60 ± 0.36 Ncm for method B, and 2.98 ± 0.26–26.38 ± 0.59 Ncm for method C, and the PRTs of methods A and B were 11.77%–44.87% higher than that of method C (P ≤ 0.016). The removal torque loss rates of methods A (12.49% ± 0.99%–65.88% ± 4.83%) and B (12.84% ± 0.96%–65.35% ± 1.95%) were 3.04%–7.74% lower than that of method C (16.58% ± 0.56%–71.10% ± 1.58%) (P ≤ 0.017). The operating time of method A was much longer than those of methods B and C (P < 0.001). The structural integrity disruption of the screw thread was observed according to the SEM results in all postloading groups. Conclusions. Method B (torquing and then loosening and immediate retorquing) increases the screw joint immediate stability by 6.28%–21.58% and the long-term stability by 11.77%–44.87% compared with method C (torquing only once), has comparable screw joint stability compared with method A (retorquing after 10 min), saves time and is recommended in clinical settings. [ABSTRACT FROM AUTHOR]

Key Clinical Message: We used a mixture of particulate bone grafts (xenografts/allografts) with tenting screws to prevent membrane collapse and covered the graft with a resorbable collagen membrane to guide bone regeneration. This strategy can exclude the need for additional procedures, such as non‐resorbable membranes and major block grafting surgeries. Although the initial outcomes are promising, continuous follow‐up is required to examine the stability of the newly regenerated bone and the long‐term success of the implant. This case demonstrates the use of particulate bone grafts covered with a resorbable collagen membrane and supported by tenting screws to correct horizontal alveolar ridge defects. A man in his 40s presented with missing maxillary anterior central and lateral incisors and required a fixed dental prosthesis. One year before, #12, #11, #21, and #22 had been extracted. The area showed horizontal and slight vertical bone loss. We used a mixture of particulate bone grafts (xenografts and allografts) with tenting screws to prevent membrane collapse and covered the graft with a resorbable collagen membrane to guide bone regeneration. After 6 months, complete bone regeneration was achieved, and the dental implants were submerged in the bone. After another 6 months, the patient was administered with a fixed dental prosthesis. This method can be used to correct horizontal alveolar ridge defects and achieve esthetic restoration without the need for more extensive procedures. [ABSTRACT FROM AUTHOR]

This poster is all about the incredible world of Pediatric Dental Implants. The amazing power of this innovation will be revolutionary to smile improvement, and boost the confidence of children suffering from tooth loss. Pediatric Dental Implants are titanium screws, that are placed in the jawbone to support prosthetic teeth. In pediatric dentistry, dental implants can be used to replace missing teeth in children who have lost them due to injury, decay, or other reasons. This can help improve their oral health, function. Traumatic injuries affect approximately 22.7% of the population worldwide, which is one of the leading reasons for tooth loss in young patients. It is used in children with congenitally missing single tooth, multiple teeth or complete Anodontia, congenital conditions like nonsyndromic hypodontia, cleft lip and palate, ectodermal dysplasia, 7P63 related disorders, acquired tooth loss (e.g. Dentoalveolar trauma, Tumour resection, Induced anodontia). Mini implants are small in diameter. They are also known as small diameter implant, narrow body implants. Various studies have found that there is a 90%-95% success rate of implants. Dental implants are a game-changer in pediatric dentistry, and provide a fantastic solution for replacing missing teeth, resulting in restoration of their smiles and boosting of their confidence. With advancements in technology, these implants will offer long lasting and predictable results. [ABSTRACT FROM AUTHOR]

• In monkey fMRI, it is essential to achieve optimal restraint of the monkey's head in the scanner. • We introduced a plastic head mask which is made from commercially available, medical thermoplastic splint material. • This plastic head mask is molded by experimenters to fit the skull of an individual monkey in a brief anesthesia session. • The plastic mask effectively suppressed the monkeys' head movements. • Using this mask, reliable retinotopic BOLD responses were obtained in the standard visual localizers. Functional magnetic resonance imaging (fMRI) in behaving monkeys has a strong potential to bridge the gap between human neuroimaging and primate neurophysiology. In monkey fMRI, to restrain head movements, researchers usually surgically implant a plastic head-post on the skull. Although time-proven to be effective, this technique could create burdens for animals, including a risk of infection and discomfort. Furthermore, the presence of extraneous objects on the skull, such as bone screws and dental cement, adversely affects signals near the cortical surface. These side effects are undesirable in terms of both the practical aspect of efficient data collection and the spirit of "refinement" from the 3R's. Here, we demonstrate that a completely non-invasive fMRI scan in awake monkeys is possible by using a plastic head mask made to fit the skull of individual animals. In all of the three monkeys tested, longitudinal, quantitative assessment of head movements showed that the plastic mask has effectively suppressed head movements, and we were able to obtain reliable retinotopic BOLD signals in a standard retinotopic mapping task. The present, easy-to-make plastic mask has a strong potential to simplify fMRI experiments in awake monkeys, while giving data that is as good as or even better quality than that obtained with the conventional head-post method. [ABSTRACT FROM AUTHOR]