Physico-Chemical comparison of four commercially available mineral trioxide aggregates / Comparación fisicoquímica de cuatro mineral trióxido agregados disponibles comercialmente

Abstract To compare the physicochemical composition of 4 MTAs commercially available in Latin America. ProRoot MTA (Dentsply, USA), MTA Angelus (Angelus, Brazil), MTA Flow (Ultradent, USA), and MTA Viarden (Viarden, Mexico) were physically and chemically compared. Scanning electron microscopy (SEM) images were obtained from the MTA powder and the prepared presentations. Energy Dispersive X-Ray Spectroscopy (EDS) analyses were performed by triplicate, to calculate the mass proportion of calcium (Ca), silicon (Si), the Ca/Si proportion among the 4 brands. Thermogravimetric analyses (TGA) were conducted (50ºC-1000ºC), and mass loss and inflection points were calculated for each material. Statistical differences for Ca and Si content were determined by ANOVA (p<0.05). SEM images showed evident differences in the appearance of both the powder and the prepared MTAs among brands. Angelus MTA showed cubic prisms not observed in the other 3 brands. ProRoot MTA and MTA Flow showed similar homogeneous structures. MTA Viarden was the less homogeneous, with random structures (>15um). When comparing the mass proportions of Ca and Si between the 4 powder samples, MTA Viarden showed a significantly lower proportions of both elements when compared with the other brands (p<0.005). TGA análisis showed a similar behavior for ProRoot MTA, MTA Angelus and MTA Flow, with less than 2% mass loss when the 1000C temperature was reached. MTA Viarden showed a mass loss of 9,94% before the 700C, indicating the presence of different content sensible to temperature degradation. The analyzed MTAs demonstrated to vary significantly in their chemical composition and physical characteristics. Clinicians must be aware of the differences between different brands of a same material, and future research should focus on the clinical implications of these differences.

Resumen Comparar la composición fisicoquímica de 4 MTA disponibles comercialmente en América Latina. Se compararon física y químicamente ProRoot MTA (Dentsply, EE. UU.), MTA Angelus (Angelus, Brasil), MTA Flow (Ultradent, EE. UU.) y MTA Viarden (Viarden, México). Se obtuvieron imágenes de microscopía electrónica de barrido (SEM) del polvo de MTA y de las presentaciones preparadas. Los análisis de espectroscopía de dispersión de energía de rayos X (EDS) se realizaron por triplicado para calcular la proporción de masa de calcio (Ca), silicio (Si), la proporción Ca/Si entre las 4 marcas. Se realizaron análisis termogravimétricos (TGA) (50ºC-1000ºC), y se calcularon las pérdidas de masa y los puntos de inflexión para cada material. Las diferencias estadísticas para el contenido de Ca y Si se determinaron mediante ANOVA (p<0,05). Los análisis SEM mostraron diferencias evidentes en la apariencia tanto del polvo como las preparaciones de los MTA, entre las diferentes marcas. MTA Angelus mostró prismas cúbicos no observados en las otras 3 marcas. ProRoot MTA y MTA Flow mostraron estructuras homogéneas similares. MTA Viarden fue el menos homogéneo, con estructuras aleatorias (>15um). Al comparar las proporciones de masa de Ca y Si entre las 4 muestras de polvo, MTA Viarden mostró proporciones significativamente más bajas de ambos elementos en comparación con las otras marcas (p<0,005). El análisis TGA mostró un comportamiento similar para ProRoot MTA, MTA Angelus y MTA Flow, con menos del 2 % de pérdida de masa al alcanzar los 1000 °C de temperatura. El MTA Viarden mostró una pérdida de masa de 9,94% antes de los 700 °C, indicando la presencia de diferentes contenidos sensibles a la degradación por temperatura. Los MTA analizados demostraron diferencias significativas en su composición química y características físicas. Los clínicos deben ser conscientes de las diferencias entre las diferentes marcas de un mismo material, y futuras investigaciones deben enfocarse en las implicaciones clínicas de estas diferencias.

Comparison of two obturation techniques on adhesion and proliferation of human periodontal ligament fibroblasts / Comparación de la adhesión y proliferación de fibroblastos periodontales humanos en dos técnicas de obturación endodóntica

The present study aimed to compare the adhesion and proliferation of human periodontal ligament fibroblasts (hPDL) in transverse sections of the teeth sealed with two different obturation techniques, BioRoot RCS/hydraulic obturation (HO) and AH-Plus/continuous-wave condensation (CWC). The techniques were tested using an in vitro model to simulate the interaction between periodontal tissues and the materials. The root canals were instrumented and sterilized. A total of 15 samples were obturated with BioRoot RCS/HO and 15 samples with AH-Plus/CWC. Then, roots were sectioned to obtain obturated teeth slices, and hPDL cells were seeded onto the root slices. The results were obtained at intervals of 4 and 24h for cell adhesion; and at 3,7,14, and 21 days for cell proliferation. Empty cell culture plates were use as controls. The cell adhesion was increased at 4 and 24h for both groups, with an increased response observed in the BioRoot RCS/HO group (p<0.05). The difference in cell proliferation was also found between experimental groups. After 14 days of culture, BioRoot RCS/HO group showed an increase response than control and AH-Plus/CWC groups (p<0.05), and after 21 days both groups behaved better than control group, with an increased response observed in the BioRoot RCS/HO group. This study demonstrated that both root canal sealers allow the attach and growth of periodontal ligament fibroblasts, with an increased biological response in the BioRoot RCS/HO group.

El presente estudio se enfocó en comparar la adhesión y proliferación de fibroblastos de ligamento periodontal humano (hPDL) en secciones transversales de raíces previamente obturadas con dos técnicas de obturación diferentes: obturación hidráulica empleando cono único de gutapercha y BioRoot RCS como sellador (HO), y obturación de condensación de onda continua y AH-Plus como sellador (CWC). Los selladores se usaron en un modelo in vitro que simula la interacción entre los tejidos periodontales y los materiales de obturación. Los conductos radiculares fueron instrumentados, esterilizados y obturados. La muestra se compuso de un total de 15 raíces con la técnica BioRoot RCS/HO y 15 raíces con la técnica AH-Plus/CWC. Las células de hPDL fueron sembradas en condiciones estándar de cultivo sobre las raíces seccionadas. Los resultados fueron obtenidos a intervalos de 4 y 24h para adhesión celular, y a los 3,5,7,14 y 21 días de cultivo para proliferación celular. La adhesión celular a las 4 y 24 horas mostró ser diferente para ambas técnicas en comparación con el grupo control, siendo más importante en el grupo BioRoot RCS/HO. La diferencia en la proliferación entre grupos se observó a los 14 días de cultivo, únicamente para el grupo BioRoot RCS/HO; Sin embargo para el día 21 ambas técnicas mostraron mayor proliferación celular que el grupo control, con mejor respuesta para el grupo BioRoot RCS/HO. Este estudio ha demostrado que ambos selladores de conductos permiten la adhesión y crecimiento de fibroblastos de ligamento periodontal, siendo el grupo BioRoot RCS/HO el que mostró mayor biocompatibilidad.

Evaluation of the Local Synergistic Effect of a Dexketoprofen and Chlorhexidine Combination in the Formalin Test.

OBJECTIVE: Evidence supports the local application of non-steroidal antiinflammatory drugs such as dexketoprofen trometamol (DXT) for pain management, but little is known about the potential antinociceptive effect of chlorhexidine gluconate (CHX) and its possible synergistic effect when combined with DXT. The aim of this study was to evaluate the local effect of a DXT-CHX combination using isobolographic analysis in a formalin pain model in rats. MATERIALS AND METHODS: Briefly, 60 female Wistar rats were used for the formalin test. Individual dose effect curves were obtained using linear regression. For each drug, the percentage of antinociception and median effective dose (ED50; 50% of antinociception) were calculated, and drug combinations were prepared using the ED50s for DXT (phase 2) and CHX (phase 1). The ED50 of the DXT-CHX combination was determined, and an isobolographic analysis was performed for both phases. RESULTS: The ED50 of local DXT was 5.3867 mg/mL in phase 2 and for CHX was 3.9233 mg/mL in phase 1. When the combination was evaluated, phase 1 showed an interaction index (II) of less than 1, indicating synergism but without statistical significance. For phase 2, the II was 0.3112, with a reduction of 68.88% in the amounts of both drugs to obtain the ED50; this interaction was statistically significant (P < .05). CONCLUSION: DXT and CHX had a local antinociceptive effect and exhibited synergistic behavior when combined in phase 2 of the formalin model.

Evaluation of dentin microroughness and composite bond strength after multiple uses of diamond burs / Evaluación de la micro rugosidad dentinaria y la resistencia adhesiva de composites tras múltiples usos de fresas de diamante

Abstract Using a bur multiple times to prepare dental structure may produce a smoother final surface on dentin than a new one. This superficial roughness may affect adhesion with resin-based materials by modifying the substrates' characteristics. The aim of this study was to evaluate the effect of multiple uses of diamond burs on dentin's superficial microroughness and bond strength with resin composite when using a self-etch adhesive. Diamond dental burs were used to simulate a preparation (dentin flat surface) on extracted third molars. Samples were distributed into groups according to burs' number of previous uses as follows: 0, 1, 5 and 10. Scanning electron microscopy images at 70x, 350x, and 1000x were used to illustrate burs' deformation. Each specimen's dentin microroughness was measured three times to compare between experimental groups and the micro-shear bond strength test (n=15) was performed for the 0 and 10 uses groups using a universal adhesive in a self- etching mode. Diamond crystals wear and dislodgements were evident among groups where the burs were used more times. As the number of uses increased the mean microroughness of the dentin surface decreased with significant differences between the 0 and 10 uses groups. No statistical differences between experimental groups resulted from bond strength tests. When using a universal adhesive in a self-etching mode, the number of previous uses of a diamond bur seems to have no significant effect on dentin/resin composite bond strength.

Resumen El uso de una fresa múltiples veces para preparar la estructura dental puede producir una superficie final más lisa en la dentina que una fresa nueva. Esta rugosidad superficial modifica las características del sustrato y puede afectar la adhesión con materiales resinosos. El objetivo de este estudio fue evaluar el efecto de los múltiples usos de las fresas de diamante sobre la micro rugosidad superficial de la dentina y la resistencia adhesiva con la resina compuesta cuando se utiliza un adhesivo de autograbado. Se utilizaron fresas dentales de diamante para simular una preparación (superficie plana de la dentina) en terceros molares extraídos. Las muestras se distribuyeron en grupos según el número de usos previos de las fresas de la siguiente manera: 0, 1, 5 y 10. Se utilizaron imágenes de microscopía electrónica de barrido a ×70, ×350 y ×1000 para ilustrar la deformación de las fresas. Se midió la micro rugosidad de la dentina de cada espécimen tres veces para comparar entre los grupos experimentales y se realizó la prueba de resistencia a la adhesión por micro cizallamiento (n=15) para los grupos de 0 y 10 usos utilizando un adhesivo universal en modo de autograbado. El desgaste de los cristales de diamante y los desprendimientos fueron evidentes entre los grupos en los que las fresas se utilizaron más veces. A medida que aumentaba el número de usos, la micro rugosidad media de la superficie de la dentina disminuyó, con diferencias significativas entre los grupos de 0 y 10 usos. En las pruebas de resistencia adhesiva no se observaron diferencias estadísticas entre los grupos experimentales. Cuando se utiliza un adhesivo universal en modo de autograbado, el número de usos previos de una fresa de diamante no parece tener un efecto significativo en la resistencia de la unión dentina/resina del composite.

Antibacterial and antifungal capacity of three commercially available mouthwashes with different concentrations of chlorhexidine / Efecto antibacteriano y antifúngico de tres enjuagues bucales comerciales con diferentes concentraciones de clorhexidina

Abstract Chlorhexidine was introduced almost seven decades ago and has a myriad of applications in dentistry. Few studies have evaluated the antimicrobial and antifungal capacity of different concentrations of chlorhexidine mouthwashes. Therefore, the aim of this study, was to evaluate in vitro, the antibacterial and antifungal capacity of three commercially available mouthwashes in Costa Rica, with different concentrations of chlorhexidine, 0.12%, 0.06%, and 0.03%. The experimental method selected was the Kirby-Bauer method to evaluate the antibacterial and antifungal effect of each compound by measuring the inhibitory effect on Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, and Candida albicans strains, exposed to the antiseptic solutions. All samples showed some degree of antibacterial and antifungal effect. Even though we provide in vitro results, our findings are of relevance since all the species used in our experiment are microorganisms that may be present in dental plaque. Our results further support evidence that oral hygiene regimens may include mouthwashes with low doses of chlorhexidine and maintain reasonable antibacterial and antifungal efficacy.

Resumen La clorhexidina se introdujo hace casi siete décadas y tiene una gran variedad de aplicaciones en odontología. Pocos estudios han evaluado la capacidad antimicrobiana y antifúngica de diferentes concentraciones de enjuagues bucales con clorhexidina. Por lo tanto, el objetivo de este estudio fue evaluar in vitro, la capacidad antibacteriana y antifúngica de tres enjuagues bucales disponibles comercialmente en Costa Rica, con diferentes concentraciones de clorhexidina, 0.12%, 0.06% y 0.03%. El método experimental seleccionado fue el método Kirby-Bauer para evaluar el efecto antibacteriano y antifúngico de cada compuesto midiendo el efecto inhibidor sobre Staphylococcus aureus, Enterococcus faecalis, Escherichia coli y Candida albicans, expuestos a la solución antiséptica. Todas las muestras mostraron algún grado de efecto antibacteriano y antifúngico. Aunque proporcionamos resultados in vitro, nuestros hallazgos son de relevancia, ya que todas las especies utilizadas en nuestro experimento son microorganismos que pueden estar presentes en la placa dental. Nuestros resultados respaldan aún más la evidencia de que los regímenes de higiene bucal pueden incluir enjuagues bucales con dosis bajas de clorhexidina y mantener una eficacia antibacteriana y antifúngica razonable.

3D-Printed Tubular Scaffolds Decorated with Air-Jet-Spun Fibers for Bone Tissue Applications.

The fabrication of instructive materials to engineer bone substitute scaffolds is still a relevant challenge. Current advances in additive manufacturing techniques make possible the fabrication of 3D scaffolds with even more controlled architecture at micro- and submicrometric levels, satisfying the relevant biological and mechanical requirements for tissue engineering. In this view, integrated use of additive manufacturing techniques is proposed, by combining 3D printing and air-jet spinning techniques, to optimize the fabrication of PLA tubes with nanostructured fibrous coatings for long bone defects. The physicochemical characterization of the 3D tubular scaffolds was performed by scanning electron microscopy, thermogravimetric analysis, differential scanning calorimetry, profilometry, and mechanical properties. In vitro biocompatibility was evaluated in terms of cell adhesion, proliferation, and cell-material interactions, by using human fetal osteoblasts to validate their use as a bone growth guide. The results showed that 3D-printed scaffolds provide a 3D architecture with highly reproducible properties in terms of mechanical and thermal properties. Moreover, nanofibers are collected onto the surface, which allows forming an intricate and interconnected network that provides microretentive cues able to improve adhesion and cell growth response. Therefore, the proposed approach could be suggested to design innovative scaffolds with improved interface properties to support regeneration mechanisms in long bone treatment.

2020: Renewing the paradigms for orofacial pain / 2020: renovando los paradigmas para el dolor orofacial

Abstract In 2020, two important changes were adapted by the international health community: a new definition of pain and a new classification for orofacial pain conditions. With these changes new tasks and challenges also emerged, and clinicians from several disciplines begun to adopt and reconsidered classic paradigms, and the policies derived from them. This new perspective article, examine the new definition of pain proposed by the International Association for the Study of Pain, and the new International Classification of Orofacial Pain; analyzing the positive impact and further perspectives of these.

Resumen En 2020, dos importantes cambios fueron adaptados por la comunidad internacional en salud: una nueva definición de dolor y una nueva clasificación para las condiciones de dolor orofacial. Con estos cambios, también emergieron nuevos retos y tareas, y los clínicos de diversas disciplinas empezaron adaptar y reconsiderar los paradigmas clásicos; y las políticas derivadas de estos. En este artículo de nueva perspectiva, examinaremos nueva definición de dolor propuesta por la Asociación Internacional para el Estudio del Dolor, y la nueva Clasificación Internacional de Dolor Orofacial; analizando el impacto positivo y las próximas perspectivas de estos cambios.

Effects of heat on seven endodontic sealers.

PURPOSE: To examine the microscopic surface features, chemical composition, and thermodynamic profile of seven endodontic sealers (AH Plus, Adseal, MTA-Fillapex, RoekoSeal, GuttaFlow 2, GuttaFlow BioSeal, and EndoRez) exposed to high-temperature changes using an endodontic obturation device. METHODS: The thermal properties were examined using scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Then, six disc-shaped specimens of each sealer were prepared and divided into two groups - a room temperature group and a heat exposure group - for analysis of surface and chemical changes using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). RESULTS: DSC analysis showed that AH Plus had the highest exothermal signal (122.9°C), while TGA analysis showed that MTA-Fillapex was most affected by increased temperature (32.4% mass loss at 230ºC). SEM analysis showed that while AH Plus and GuttaFlow BioSeal maintained their surface integrity after heat exposure, the EDS profiles demonstrated changes in the chemical composition of the sealers after heat exposure for 5 s. High-temperature exposure had a negative impact on the properties of five of the sealers (Adseal, MTA-Fillapex, RoekoSeal, GuttaFlow 2, and EndoRez). CONCLUSION: AH Plus and GuttaFlow BioSeal showed minimal changes upon high-temperature exposure, suggesting their suitability for thermal endodontic obturation techniques.

Management of dental caries lesions in Latin American and Caribbean countries.

Caries management at the lesion level is dependent on the lesion activity, the presence of a cavitation (either cleanable or non-cleanable), and lesion depth as evaluated via radiographic examination. A variety of non-invasive, micro-invasive, and minimally invasive treatment (with or without restoration) options are available for primary and permanent teeth. Non-invasive strategies include oral hygiene instructions, dietary counseling, and personal as well as professional use of fluoridated products that reduce demineralization and increase re-mineralization. Micro-invasive procedures include the use of occlusal resin sealants and resin infiltrants, while minimally invasive strategies comprise those related to selective removal of caries tissues and placement of restorations. Deep caries management includes indirect pulp capping, while exposed pulp may be treated using direct pulp capping and partial or complete pulpotomy. The aim of the present study was to review available evidence on recommended preventive and restorative strategies for caries lesions in Latin American/Caribbean countries, and subsequently develop evidence-based recommendations for treatment options that take into consideration material availability, emphasize ways to adapt available treatments to the local context, and suggest ways in which dentists and health systems can adopt these treatments.

Synthesis of a PVA drug delivery system for controlled release of a Tramadol-Dexketoprofen combination.

The local administration of analgesic combinations by means of degradable polymeric drug delivery systems is an alternative for the management of postoperative pain. We formulated a Tramadol-Dexketoprofen combination (TDC) loaded in poly(vinyl alcohol) (PVA) film. Films were prepared by the solvent casting method using three different molecular weights of PVA and crosslinking those films with citric acid, with the objective of controlling the drug release rate, which was evaluated by UV-vis spectrometry. Non-crosslinked PVA films were also evaluated in the experiments. Differential scanning calorimetry (DSC) analysis of samples corroborated the crosslinking of PVA by the citric acid. Blank and loaded PVA films were tested in vitro for its impact on blood coagulation prothrombin time (PT) and partial thromboplastin time (PTT). The swelling capacity was also evaluated. Crosslinked PVA films of higher-molecular weight showed a prolonged release rate compared with that of the lower-molecular-weight films tested. Non-crosslinked PVA films released 11-14% of TDC. Crosslinked PVA films released 80% of the TDC loaded (p < 0.05). This suggests that crosslinking films can modify the drug release rate. The blank and loaded PVA films induced PT and PTT in the normal range. The results showed that the polymeric films evaluated here have the appropriate properties to allow films to be placed directly on surgical wounds and have the capacity for controlled drug release to promote local analgesia for the control of postoperative pain.

Management of dental caries lesions in Latin American and Caribbean countries

Abstract Caries management at the lesion level is dependent on the lesion activity, the presence of a cavitation (either cleanable or non-cleanable), and lesion depth as evaluated via radiographic examination. A variety of non-invasive, micro-invasive, and minimally invasive treatment (with or without restoration) options are available for primary and permanent teeth. Non-invasive strategies include oral hygiene instructions, dietary counseling, and personal as well as professional use of fluoridated products that reduce demineralization and increase re-mineralization. Micro-invasive procedures include the use of occlusal resin sealants and resin infiltrants, while minimally invasive strategies comprise those related to selective removal of caries tissues and placement of restorations. Deep caries management includes indirect pulp capping, while exposed pulp may be treated using direct pulp capping and partial or complete pulpotomy. The aim of the present study was to review available evidence on recommended preventive and restorative strategies for caries lesions in Latin American/Caribbean countries, and subsequently develop evidence-based recommendations for treatment options that take into consideration material availability, emphasize ways to adapt available treatments to the local context, and suggest ways in which dentists and health systems can adopt these treatments.

E-Learning in Dental Schools in the Times of COVID-19: A Review and Analysis of an Educational Resource in Times of the COVID-19 Pandemic / E-learning en las escuelas de odontología en los tiempos de COVID-19: Una revisión y análisis de un recurso educativo en tiempos de la pandemia de COVID-19

Abstract While countries are facing different stages in their COVID-19 infection rates, worldwide there are millions of students affected by universities' facilities closures due to the pandemic. Some institutions have enforced strategies to transfer some courses to a virtual modality, but many Dental Schools have been challenged to deal with a situation which requires emergency measures to continue the academic course in the middle of lock-downs and social distancing measures. Despite the fact that the number of online academic programs available, especially graduate programs, has increased in diverse modalities, this pandemic forced e-learning processes to develop abruptly. The likelihood of using e-learning strategies in dentistry was substantiated in the scientific literature and an overview of these opportunities is presented. Additionally, the experience of the University of Costa Rica Faculty of Dentistry is presented, as it was evident that some of the key elements in a e-learning environment needed a quick enhancement and initiation of some processes was required. First, it was necessary to categorize the academic courses depending on their virtualization's possibility (curricula analysis and classification), to better understand the extent of the impact and the work needed to contain, as far as the possibilities allowed, negative consequences on students learning process. Second, teachers needed further training in the application of virtual strategies which they hadn't used before. do Third, an evaluation of the students' conditions and needs was conducted in a form of a survey. Finally, teachers and students activated the available virtual platforms. For many Dental Schools, this virtualization process is an ongoing progress although it was abruptly imposed, but this moment indeed represents an enormous opportunity to move forward and get immerse in the virtualization environment as a teaching/learning experience.

Resumen Mientras muchos países están enfrentando distintas etapas en sus tasas de contagio de COVID-19, millones de estudiantes alrededor del mundo han sido afectados por el cierre de instalaciones universitarias debido a la pandemia. Algunas instituciones han aplicado estrategias para transferir algunos cursos a una modalidad virtual, pero muchas facultades de odontología se han visto enfrentadas a una situación que requiere medidas de emergencia para continuar el curso académico en medio de bloqueos y medidas de distanciamiento social. A pesar de que el número de programas académicos en línea disponibles, especialmente los programas de postgrado, ha aumentado en diversas modalidades, esta pandemia obligó a desarrollar abruptamente los procesos de aprendizaje electrónico. La probabilidad de utilizar estrategias de aprendizaje electrónico en odontología se vió corroborada en la literatura científica y se presenta una visión general de estas oportunidades. Además, se presenta la experiencia de la Facultad de Odontología de la Universidad de Costa Rica, ya que fue evidente que algunos de los elementos clave en un entorno de aprendizaje electrónico necesitaban una rápida mejora y se requería la iniciación de algunos procesos. En primer lugar, era necesario clasificar los cursos académicos en función de las posibilidades de su virtualización (análisis y clasificación de los planes de estudio), para comprender mejor el alcance de las repercusiones y la labor necesaria para contener, en la medida de las posibilidades, las consecuencias negativas en el proceso de aprendizaje de los estudiantes. En segundo lugar, los profesores necesitaban más capacitación en la aplicación de estrategias virtuales que no habían utilizado antes. En tercer lugar, se realizó una evaluación de las condiciones y necesidades de los estudiantes en forma de encuesta. Finalmente, los profesores y estudiantes activaron las plataformas virtuales disponibles. Para muchas escuelas de odontología, este proceso de virtualización es un continuo progreso y a pesar de haber tenido un inicio abrupto, pero este momento representa, de hecho, una enorme oportunidad para avanzar y sumergirse en el entorno de la virtualización como una experiencia de enseñanza/aprendizaje.

Rehabilitation of anterior maxilla with a novel hyperbolic profile transmucosal implant in elderly patients.

BACKGROUND: This study aims to evaluate soft and hard tissues response of a two-piece implant placed nonsubmerged in elderly patients' anterior maxilla. Marginal bone level and Pink Esthetic Score (PES) were evaluated up to 24 months. METHODS: Twelve healthy consecutive patients (mean age 65.8±5 years; 65.5 median) were included in the study. Implants were inserted with flapless technique after 3 months or immediately after extraction. The smooth machined neck of the implant was characterized by a hyperbolic neck which follows biologically oriented preparation technique (BOPT) principles. A customized abutment and a provisional resin crown was positioned with care to avoid excessive soft tissue compression after 3 months, according with BOPT technique. A definitive ceramic crown was positioned after approx. 4 months. RESULTS: After 24 months all implants were stable and osseointegrated. PES improved at 6 and 12 months recalls, remaining stable at 24 months, indicating a healthy soft and hard tissue response. No complications were observed. Impression procedures and provisional/definitive crown cementation resulted simple and free from complications. The hyperbolic profile allowed the preparation of prosthetic crown free from any gingival tissue pressure to create the adequate soft tissue contour. CONCLUSIONS: The use of hyperbolic profile implant associated with the transmucosal (not-submerged) technique is a safe procedure that allow the preservation of soft and hard tissue also in elderly patients.

Nocebo/Placebo Effects in Dental Practice: Two Key Protagonists / Efectos Nocebo/Placebo en la práctica dental: Dos protagonistas clave

ABSTRACT Understanding the possible effects that a patient's psycho-neurobiological processes (such as the nocebo effect) may have on the every-day dental treatments, could assist the clinicians in preventing the onset of adverse events not related directly with the clinical procedure. At the same time, employing pathways to trigger plausible placebo effects could aid the clinician to enhance the outcome of ordinary clinical procedures and the patient's perspective. Identified factors, which could lead both to positive or negative effects, may be present in different ways. Prior personal experiences, second-hand information, alternative medicine, catastrophizing or patient motivation; all could have an indirect effect in the treatment outcome. A well-informed clinician should use such factors to individualize each patient treatment.

RESUMEN Comprender los posibles efectos que los procesos psico-neurobiológicos de un paciente (como el efecto nocebo) pueden tener en los tratamientos dentales diarios, podría ayudar a los clínicos a prevenir la aparición de eventos adversos que no estén relacionados directamente con el procedimiento clínico. Al mismo tiempo, el uso de vías para favorecer posibles efectos placebo podría ayudar al clínico a mejorar el resultado de sus procedimientos rutinarios y la perspectiva del paciente. Los factores identificados, ya sean positivos o negativos, pueden estar presentes de diferentes maneras. Experiencias personales anteriores, información de segunda mano, medicina alternativa, actitud catastrófica o motivación del paciente; todos podrían tener un efecto indirecto en el resultado del tratamiento. Un médico bien informado debe usar dichos factores para individualizar el tratamiento de cada paciente.

Local Ketamine Improves Postoperative Analgesia After Third Molar Surgery.

PURPOSE: Evidence exists to support the peripheral analgesic effect of local administration of ketamine (LAK) after third molar surgery. The aim of the present systematic review and meta-analysis was to determine the efficacy of LAK in the control of pain, swelling, and trismus after third molar surgery. MATERIALS AND METHODS: The study design was a systematic review with a meta-analysis of the effect of LAK after third molar surgery. A search in electronic databases was performed from September 2017 to February 2019. Only prospective clinical trials and randomized controlled trials that had evaluated LAK after third molar surgery were included. The meta-analysis was based on the random effects model. The outcome measures evaluated were postoperative acute pain, swelling, and trismus. The estimated overall effect size was a standardized mean difference (SMD). RESULTS: A total of 110 study subjects (men and women aged 18 to 50 years) were evaluated for the analgesic effect. The SMD showed a significant analgesic effect (postoperative pain control) favoring LAK (SMD, -1.7403; 95% confidence interval [CI], -2.45 to -1.04). Evaluation of the anti-inflammatory effect of LAK included 105 study subjects and resulted in significantly less swelling in the first postoperative day (SMD, -0.6169; 95% CI, -1.1654 to -0.0683). However, LAK did not reduce the incidence of trismus after third molar surgery (SMD, -0.7241; 95% CI, -2.2765 to 0.8284). CONCLUSIONS: The use of LAK can reduce the incidence and severity of postoperative pain after third molar surgery and had an anti-inflammatory effect, although only in the first postoperative day. However, LAK had no effect on trismus reduction after third molar surgery.

Evaluation of Surgical Bur Deformation and Bone Surface Roughness After Multiple Uses.

PURPOSE: The aim of the present in vitro study was to microscopically evaluate and describe the deformation of Lindeman surgical burs and the bone surface roughness after repeated osteotomies and sterilization cycles. MATERIALS AND METHODS: Twenty-one Lindeman surgical burs were analyzed under scanning electron microscopy (SEM) to evaluate the damage of the bur's integrity after 0, 1, 3, 5, 7, or 9 osteotomies on bovine ribs. Eighteen bone specimens were obtained after osteotomy for roughness analysis using profilometry. One-way analysis of variance was used to compare the mean roughness values across the experimental groups, and P ≤ .05 was considered to indicate statistical significance. RESULTS: Representative SEM images illustrated that all analyzed burs presented with some type of deformation at both the tip and the body, even after their first use. The mean roughness values were independent of the number of uses (P > .05); however, the standard deviation increased with the number of uses of the burs. CONCLUSIONS: These results suggest that even after their first use, rotatory surgical burs will have some type of deformation and that their cutting efficiency on the bone will vary and will be difficult to predict.

Pharmacological Synergism: A Multimodal Analgesia Approach to Treat Dental Pain / Sinergismo Farmacológico: Un enfoque de analgesia multimodal para el manejo de dolor dental

Abstract Dental pain is usually managed by clinical interventions and pharmacological coadjuvants such as NSAIDs. However, its perception and modulation is mediated by different nociceptive mechanisms and these strategies can be insufficient. The multimodal analgesia refers to the use of 2 or more analgesic drugs that attenuate or blockade different mechanisms of pain, obtaining a greater clinical effect. Within this concept, pharmacological synergism plays a leading role, combining different molecules in lower doses to diminish also side effects. Since there are no standard prescriptions to be use in all the patients, multimodal approaches allow the clinician to make responsible effective combinations, individualizing analgesia as the pathway to success.

Resumen El dolor dental generalmente se trata con intervenciones clínicas y coadyuvantes farmacológicos como los AINEs. Sin embargo, su percepción y modulación está mediada por diferentes mecanismos nociceptivos y estas estrategias pueden ser insuficientes. La analgesia multimodal se refiere al uso de 2 o más fármacos analgésicos que atenúan o bloquean diferentes mecanismos de dolor, obteniendo un mayor efecto clínico. Dentro de este concepto, el sinergismo farmacológico juega un papel importante, combinando diferentes moléculas en dosis más bajas para disminuir también los efectos secundarios. Dado que no hay prescripciones estándar para ser usadas en todos los pacientes, los enfoques multimodales permiten al clínico realizar combinaciones responsables y eficaces, individualizando la analgesia como el camino hacia el éxito.

Conocimiento de protocolos de terapia antibiótica por estudiantes de Odontología de universidades costarricenses / Knowledge of Antibiotic Therapy Protocols by the Students of Costa Rican Dental Schools

RESUMEN El conocimiento de protocolos antibióticos es escencial para garantizar su correcto uso en nuestros pacientes. Una mala selección de terapia antibiótica, puede estar asociada con el desarrollo de efectos adversos, inefectividad terapéutica o desarrollo de resistencia bacteriana entre otros. El objetivo de este estudio fue evaluar el nivel de conocimiento sobre el uso de los protocolos de antibioticoterapia, por parte de los estudiantes que se encontraban realizando la práctica clínica de su Universidad. El estudio se realizó en tres universidades costarricenses que imparten la carrera de Odontología. Se realizó un estudio descriptivo de tipo transversal, donde se aplicó un cuestionario a los estudiantes. Dicho instrumento constó de treinta preguntas cerradas, dividido en cinco segmentos, donde se evaluaron generalidades de los antibióticos, indicaciones y condiciones clínicas de su uso, protocolos especiales del uso de los antibióticos, datos demográficos y generalidades académicas de cada uno de los participantes. Se observó que los estudiantes de Odontología obtuvieron un 40% de respuestas correctas relacionadas al conocimiento de generalidades de los antibióticos, un 40% de respuestas acertadas en las preguntas sobre indicaciones clínicas y un 32.8% de las preguntas sobre protocolos especiales fue correcta. El conocimiento de los estudiantes de las universidades participantes es bajo, por lo que se recomienda reforzar los programas de estudio, la implementación de seminarios que refuercen esta área, así como la constante revisión de literatura que actualice los conocimientos adquiridos en la disciplina de la Farmacología, especialmente en el uso y manejo de antibióticos.

ABSTRACT The knowledge of antibiotic protocols is essential to guarantee its correct use in our patients. A poor selection of antibiotic therapy may be associated with the development of adverse effects, therapeutic ineffectiveness or development of bacterial resistance among others. The aim of this study was to assess the level of knowledge of antibiotic therapy protocols in students of the last year of Dentistry during their clinical practice in different costa rican universities. The study was performed at three of the costa rican universities that offer the career of Dentistry. A descriptive transversal study was performed by applying a questionnaire in different dental schools, to the students undergoing clinical practice. The questionnaire consisted in thirty closed questions and was divided in five segments, assessing the knowledge of general aspects of antibiotics, indications and clinical conditions for antibiotic therapy, and the special protocols in this field. Demographic data and certain academic of the students interviewed were also recorded. From the students who participated in the study, 40% answer correctly the segment concerning general knowledge of antibiotics, 40% to the segment of clinical indications for antibiotic protocols and only the 32,8% of the answers of special antibiotic protocols was correct. The general knowledge of antibiotic protocols of the students surveyed was low. It is recommended to reinforce the study programs and the implementation of seminars to strengthen this area, as well to reinforce the discipline of constant revision of literature in order to update their acquired knowledge in Pharmacology.

Evaluation of Microleakage by Gas Permeability and Marginal Adaptation of MTA and BiodentineTM Apical Plugs: In Vitro Study / Evaluación de la microfiltración por permeabilidad de gas y adaptación marginal de tapones apicales de MTA y BiodentineTM: Estudio in vitro

Abstract The endodontic treatment of teeth with incomplete development is always a complex task. Nowadays, biomaterials such as bioceramics offers promising clinical evidence that supports its use. However, the standardization of its use for apexification purpose still needs a deeper understanding of the materials' behavior. The aim of this investigation was to evaluate the marginal adaptability and microleakage by gas permeability of MTA and Biodentine™ apical plugs in an in vitro model. Materials and methods: Twenty- four single rooted human teeth were selected according to previously stablished inclusion criteria. All samples were prepared obtaining standard cylindrical internal canals with a diameter of 1.3 mm. Root canals were gently rinsed using 5.25% sodium hypochlorite and EDTA 17%. The apical 3mm and remaining coronal dental structure were sectioned to obtain 10mm roots. Roots were randomly assigned to 3 different groups as follows: GROUP A: MTA (n=10), GROUP B: Biodentine™ (n=10) and Group C: Control (positive n=1, negative n=3). MTA and Biodentine™ were prepared according to manufacturer's indications, and apical plugs of 4mm were passively placed in the correspondent teeth. All samples were stored in saline solution for 7 days at 37°C before evaluation. Samples were mounted in cylindrical sample-holders using epoxy resin. Microleakage was evaluated with an automatic permeability detector that calculates nitrogen diffusion between the material-root interphase. After microleakage evaluation, the samples were recovered and analyzed by scanning electron microscopy (SEM). Microleakage results were analyzed using Chi-square and adaptation was evaluated with a descriptive analysis. Results: None of the evaluated materials completely avoided the nitrogen microleakage (positive leakage of 10% and 20% of samples for MTA and Biodentine™ respectively); with no statistical significant difference between groups (p=0.527). All apical plugs showed good adaptation under SEM, at 30x, 200x, 1000x and 2500x; with microscopical structures similar to previous reports. Conclusions: Both bioceramics behave similar when used as apical barriers to avoid permeability, with acceptable marginal adaptation. Further in vivo studies are needed to validate these results.

Resumen El tratamiento endodóntico de dientes con desarrollo incompleto es siempre una tarea compleja. Hoy en día, biomateriales como las biocerámicas ofrecen una evidencia clínica prometedora que apoya su uso. Sin embargo, la estandarización de su uso para fines de apexificación todavía necesita una comprensión más profunda del comportamiento de los materiales. El objetivo de esta investigación fue evaluar la adaptabilidad marginal y microfiltración por permeabilidad de gas de los tapones apicales de MTA y Biodentine™ en un modelo in vitro. Materiales y métodos: Veiticuatro dientes humanos uniradiculares fueron seleccionados meticulosamente según criterios de inclusión previamente establecidos. Todas las muestras fueron preparadas con canales cilíndricos internos estandarizados de 1,3 mm de diámetro. Los conductos radiculares fueron gentilmente lavados con hipoclorito de sodio al 5,25% y EDTA al 17%. La estructura dental apical de 3 mm y la coronal restante se seccionó para obtener raíces de 10 mm de longitud. Las raíces se asignaron aleatoriamente a 3 grupos diferentes de la siguiente manera: GRUPO A: MTA (n = 10), GRUPO B: Biodentine™ (n = 10) y Grupo C: Control (n = 1 positivo, n = 3 negativos). El MTA y Biodentine™ se prepararon de acuerdo con las indicaciones de los fabricantes, y se colocaron pasivamente los tapones apicales de 4 mm en los dientes correspondientes. Todas las muestras se almacenaron en solución salina durante 7 días a 37ºC antes de la evaluación. Las muestras se montaron en porta-muestras cilíndricos utilizando resina epóxica. La microfiltración se evaluó con un detector de permeabilidad automática que calcula la difusión de nitrógeno entre la interfase material-raíz. Después de la evaluación de microfiltración, las muestras fueron recuperadas y analizadas por microscopía electrónica de barrido (SEM). Los resultados de microfiltración se analizaron utilizando una prueba estadística de Chi-cuadrado y la adaptación se evaluó con un análisis descriptivo. Resultados: Ninguno de los materiales evaluados evitó completamente la microfiltración de nitrógeno (fuga positiva de 10% y 20% de muestras para MTA y Biodentine™, respectivamente); sin diferencias estadísticamente significativas entre los grupos (p = 0,527). Todos los tapones apicales mostraron una buena adaptación bajo SEM, a 30x, 200x, 1000x y 2500x; con morfologías similares a las previamente reportadas. Conclusiones: ambas biocerámicas se comportan de forma similar cuando se usan como barreras apicales para evitar la permeabilidad de gas, con adaptación marginal aceptable. Se necesitan más estudios in vivo para validar estos resultados.