Role of Dentistry in Humanitarian Projects: Knowledge and Perspective of Future Professionals on the World of Volunteering in Spain.

Non-governmental organizations (NGOs) in dentistry seek to promote the improvement on oral health in the most disadvantaged regions. The objective of this study is to identify the level of knowledge, expectations, and motivations that dental school students have about volunteering in dentistry, as well as to evaluate possible differences in these variables depending on their level of dental training. During the month of September 2022, a voluntary and anonymous online survey was carried out among all the students at the Dentistry School of Oviedo University. There were 5 questions to judge knowledge about global oral health course. 12 additional questions were included to assess the willingness to volunteer in international setting, the volunteer profile, as well as the most effective means to improve oral health in host communities. None of the students from our center had participated as a volunteer in dental NGOs, but up to 64.4% of them had considered their collaboration. The level of knowledge about global oral health obtained was low, with the percentage of correct answers ranging between 14.4% (in the question about the ideal patient/dentist ratio) and 57.8% (in the question about the fluoride concentration in drinking water). Majority of dental students (98.9%) were not aware that basic package of oral care was created by WHO. Significantly, the students of the clinical courses showed a greater motivation to volunteer.

Ag- and Sr-enriched nanofibrous titanium phosphate phases as potential antimicrobial cement and coating for a biomedical alloy.

Biomaterials and their surfaces regulate the biological response and ultimately the quality of healing at a possible site of implantation. The physical, chemical and topographical properties of implants' surfaces play a decisive role in the biological integration process for their immediate loading and long-term success. Since at this level of biological interaction nano-dimensionality is basically entailed, bio-functional nanostructured composites either as filling/cement or coating to metallic implants are required. This study shows the possibility of synthesizing two phases of nanostructured titanium phosphate (π and ρ polymorphs) and enriching them with silver nanoparticles and strontium. More importantly, Ag-Sr-enriched nanostructured π­titanium phosphate is induced to grow on a commercially available titanium alloy (Ti-6Al-4V), widely used in orthopedic and dental implants, under highly controlled conditions. Structural and microscopic studies, using XRD, HRTEM and SEM altogether confirm the resultant phases and their enrichment with strontium and silver nanoparticles with an average particle size around 6 nm. Using confocal laser scanning microscopy, the surface roughness was measured and is found to lay at the interface between the nanosized and microsized topologies. Ion release assessments showed that the presence of strontium controlled the release rate of silver ions and this could be beneficial in terms of decreasing the accompanied cytotoxicity that is usually encountered at high concentrations of silver release. Antimicrobial and cell proliferation assays have proved that enriching titanium phosphate with strontium and silver nanoparticles has improved their antimicrobial properties, while the cytotoxicity could be controlled.

A New Technique for Direct Fabrication of Fiber-Reinforced Composite Bridge: A Long-Term Clinical Observation.

The use of fiberglass in dentistry has increased due to the improvements in the development of adhesive techniques reducing the cost of treatment and avoiding abutment tooth craving. The present study aims to evaluate the clinical usefulness of the new technique to fabricate a direct fiber-reinforced composite bridge (FRCB) over a long period of time. Twenty-one FRCB were performed with the new direct technique on 21 patients with a mean age of 58.85 years and female predominance in the Faculty of Dentistry of Oviedo (Spain). The framework design releases the embrasures allowing adequate interproximal brushing, avoidance of periodontal disease and interproximal caries. A baseline examination was performed and the patients were examined regularly at six-month intervals (nine years' follow-up). The restorations were also evaluated by an examiner using parameters to check their stability, longevity and the lack of periodontal disease. The most frequent location was the maxillary premolar region and the purpose of the restorations was to give a definitive bridge in 100% of the patients. Only one total debonding of the prostheses was detected during the observation period at 24 months and three partial adhesive-cohesive veneering composite fractures at the pontic after 60, 72 and 84 months, respectively. Kaplan-Meier was performed to detect the overall survival rate of the restorations at the end of the follow-up. Nine-year survival rates for the FRCB was 95.2%. All the cases had a clinically acceptable periodontal condition and an interproximal absence of caries in the abutment teeth. Currently, this type of restoration allows a minimally invasive aesthetic and is an affordable procedure, being a good alternative to other types of treatments.

Does the transversal screw design increase the risk of mechanical complications in dental implants? A finite elements analysis.

The transversal screw was introduced in order to overcome some disadvantages of the transocclusal screw. However, its mechanical risk has not been studied sufficiently. The main purpose of this research was to assess and compare stress distribution in the screws and abutment of a single-crown implant with transversal and transocclusal screw models. Two 3D models were assembled to analyse a single-implant-supported prosthesis with transversal and transocclusal screws embedded in the jawbone. The crown was subjected to a static load of value 300 N with different levels of inclination. The transversal screw model, with an axial load of 15°, was the one with lowest stress values in all its components. However, the stress was greater with more inclined loads when compared with the transocclusal model. The prosthetic transversal screw showed much less stress than the rest of the components for any load inclination. The transversal screw design is the option with the lowest risk of mechanical complications, both in the prosthetic screw and in the abutment screw, when applying forces of lower inclination. The more oblique forces favoured a better biomechanical environment in the abutment and its screw in the transocclusal screw model.

Mandibular Flexure and Peri-Implant Bone Stress Distribution on an Implant-Supported Fixed Full-Arch Mandibular Prosthesis: 3D Finite Element Analysis.

PURPOSE: The purpose of this study was to evaluate and compare the effect of three mandibular full-arch superstructures on the peri-implant bone stress distribution during mandibular flexure caused by mid-opening (27 mm) and protrusion mandibular movements. MATERIALS AND METHODS: Three-dimensional finite element models were created simulating six osseointegrated implants in the jawbone. One model simulated a 1-piece framework and the other simulated 2-piece and 3-piece frameworks. Muscle forces with definite direction and magnitude were exerted over areas of attachment to simulate multiple force vectors of masticatory muscles during mandibular protrusion and opening. RESULTS: During the movement of 27.5 mm jaw opening, the 1-piece and 3-piece superstructures showed the lowest values of bone stress around the mesial implants, gradually increasing towards the distal position. During the protrusion movement, bone stress increased compared to opening for any implant situation and for a divided or undivided framework. The 3-piece framework showed the highest values of peri-implant bone stress, regardless of the implant situation. CONCLUSIONS: The undivided framework provides the best biomechanical environment during mandibular protrusion and opening. Protrusion movement increases the peri-implant bone stress. The most mesial implants have the lowest biomechanical risk.

Axiografía y registros posicionales en la determinación de la inclinación condílea / Axiography and plastic bite records for the adjustement of the condilar trayectory inclination angle

Conocida la importancia de la ITC y de su ajuste en el articulador para un buen resultado clínico y teniendo en cuenta que se puede determinar por diferentes procedimientos, nuestro objetivo es valorar si existe concordancia, a nivel de este parámetro, utilizando dos métodos distintos para su registro como son la axiografia y los registros posicionales de cera (RPC). Material y método: se realizaron RPC y axiografías a 16 pacientes y se valoró la concordancia entre ambos mediante el índice kappa de Cohen. Conclusión: el grado de concordancia entre estos dos métodos de registro es insignificante( índice Kappa entre 0 y 0,2) (AU)

Taking into account the well-know importane of the condilar path inclination angle and its adjustment in the articulator for a good clinical result, our aim is to see if there is concordance between two different methods: axiography and wax positional bite records. Material and method: axiographies and wax bite records were taken to 16 patients. Throughout the results we obtained we were able to see the concordance between these two methods with Cohen´s kappa index. Conclussion: the concordance between these methods was insignificant (kappa index 0 and 0,2) (AU)

Carga inmediata: situación actual / Immediate loading: current situation

En muchas ocasiones, la adopción de los protocolos clásicos de carga de los implantes no satisface las exigencias de pacientes y profesionales, por lo que la carga inmediata supone una importante línea de investigación en la Implantología moderna. Cada vez hay una mayor cantidad de publicaciones científicas referentes a esta materia, que permiten resolver un creciente número de casos de manera predecible, reduciendo al mínimo los tiempos de espera y consiguiendo nuestra satisfacción y, sobre todo, la del paciente. La estabilidad primaria, reducción de micromovimientos, microtopografía y longitud de los implantes, torque de inserción, el tipo de prótesis y la oclusión parecen ser factores determinantes en el éxito de la carga inmediata. En determinadas situaciones clínicas, como rehabilitaciones totales mandibulares, un gran número de estudios avalan resultados similares a los conseguidos con protocolos convencionales; sin embargo, y aunque es posible encontrar en la literatura tasas de éxito muy altas en casi todas las situaciones clínicas, hay algunas que requieren actuar con cautela a la espera de un mayor número de publicaciones (AU)

Many times, classical loading protocols on implants do not satisfy the expectations of both patients and clinicians. Therefore, immediate loading is supposed to be an interesting line of investigation in modern implantology. There are an important number of scientific publications available about this option, which makes it possible to solve a growing number of cases, in a predictable way, reducing waiting times and providing satisfaction to professionals and, most of all, to patients. Primary stability, reduction of micromovements, implant microtopography and length, insertion torque, prosthesis design and occlusion seem to be determinant factors for success in immediate loading. In several clinical situations, such as full mandibular restorations, a great amount of studies demonstrates similar results as the ones achieved with conventional protocols; nevertheless, although it is possible to find in the literature high success rates in most clinical situations, there are a few ones that require acting with caution until we have more publications at our disposal (AU)

Axiografía y registros posicionales en la determinación de la inclinación condílea / Axiography and plastic bite records for the adjustement of the condilar trayectory inclination angle

Conocida la importancia de la ITC y de su ajuste en el articulador para un buen resultado clínico y teniendo en cuenta que se puede determinar por diferentes procedimientos, nuestro objetivo es valorar si existe concordancia, a nivel de este parámetro, utilizando dos métodos distintos para su registro como son la axiografia y los registros posicionales de cera (RPC). Material y método: se realizaron RPC y axiografías a 16 pacientes y se valoró la concordancia entre ambos mediante el índice kappa de Cohen. Conclusión: el grado de concordancia entre estos dos métodos de registro es insignificante( índice Kappa entre 0 y 0,2)

Taking into account the well-know importane of the condilar path inclination angle and its adjustment in the articulator for a good clinical result, our aim is to see if there is concordance between two different methods: axiography and wax positional bite records. Material and method: axiographies and wax bite records were taken to 16 patients. Throughout the results we obtained we were able to see the concordance between these two methods with Cohen´s kappa index. Conclussion: the concordance between these methods was insignificant (kappa index 0 and 0,2)

Carga inmediata: situación actual / Immediate loading: current situation

En muchas ocasiones, la adopción de los protocolos clásicos de carga de los implantes no satisface las exigencias de pacientes y profesionales, por lo que la carga inmediata supone una importante línea de investigación en la Implantología moderna. Cada vez hay una mayor cantidad de publicaciones científicas referentes a esta materia, que permiten resolver un creciente número de casos de manera predecible, reduciendo al mínimo los tiempos de espera y consiguiendo nuestra satisfacción y, sobre todo, la del paciente. La estabilidad primaria, reducción de micromovimientos, microtopografía y longitud de los implantes, torque de inserción, el tipo de prótesis y la oclusión parecen ser factores determinantes en el éxito de la carga inmediata. En determinadas situaciones clínicas, como rehabilitaciones totales mandibulares, un gran número de estudios avalan resultados similares a los conseguidos con protocolos convencionales; sin embargo, y aunque es posible encontrar en la literatura tasas de éxito muy altas en casi todas las situaciones clínicas, hay algunas que requieren actuar con cautela a la espera de un mayor número de publicaciones

Many times, classical loading protocols on implants do not satisfy the expectations of both patients and clinicians. Therefore, immediate loading is supposed to be an interesting line of investigation in modern implantology. There are an important number of scientific publications available about this option, which makes it possible to solve a growing number of cases, in a predictable way, reducing waiting times and providing satisfaction to professionals and, most of all, to patients. Primary stability, reduction of micromovements, implant microtopography and length, insertion torque, prosthesis design and occlusion seem to be determinant factors for success in immediate loading. In several clinical situations, such as full mandibular restorations, a great amount of studies demonstrates similar results as the ones achieved with conventional protocols; nevertheless, although it is possible to find in the literature high success rates in most clinical situations, there are a few ones that require acting with caution until we have more publications at our disposal