Niveles bajos de vitamina D y su efecto en la oseointegración: revisión sistemática / Low levels of vitamin D and effect on osseointegration: a systematic review

Introducción: la vitamina D es una hormona que se sintetiza por células de la piel mediante la luz ultravioleta (UV) y se obtiene a través de la dieta. La relación que se establece entre la deficiencia de vitamina D y el fracaso en injertos óseos o implantes se basa en las alteraciones inmunológicas e inflamatorias debido al vínculo que existe con la inmunidad innata y adaptativa. Objetivo: identificar los factores que se presentan en el periodonto cuando existen niveles bajos de vitamina D y se realizan tratamientos periodontales como injertos óseos e implantes. Material y métodos: se realizó la búsqueda primaria de artículos en bases de datos PubMed y Google Académico (en español e inglés), de acuerdo con las palabras claves: deficiencia, vitamina D, implantología y oseointegración. Resultados: la vitamina D afecta y predispone al rechazo de injertos, ausencia de oseointegración en implantes debido a la inmunomodulación. Conclusión: el éxito del tratamiento se vuelve predecible cuando se encuentran niveles óptimos de vitamina D en conjunto con técnicas de abordaje quirúrgico correctas que permitan generar una integración ideal de los tejidos periodontales (AU)

Introduction: vitamin D is a hormone that is synthesized by skin cells using UV light and consumed through the diet. The relationship established between vitamin D deficiency and the failure of bone grafts or implants is based on immunological and inflammatory alterations due to the intimate link with innate and adaptive immunity. Objective: to identify the factors that occur in the periodontium when there are low levels of vitamin D and periodontal treatments such as bone grafts and implants are performed. Material and methods: a search for articles was carried out in PubMed and Google Scholar (Spanish and English). Results: vitamin D affects and predisposes to graft rejection, absence of osseointegration in implants due to immunomodulation. Conclusion: the success of the treatment becomes predictable when optimal levels of vitamin D are found together with the correct surgical approach techniques that allow the generation of an ideal integration of the periodontal tissues.(AU)

The influence of haematogenous bone marrow on the early osseointegration of a titanium implant which penetrates the endosteum / La influencia de la médula ósea hematógena en la osteointegración temprana de un implante de titanio que penetra en el endostio

SUMMARY: The utility of metallic bio-medical implants in osseous or dental affections is irrefutable. The paper aims to test the tolerance of the bone marrow to titanium implants. Titanium implants were inserted in the femur of 11-months old rabbits. The implants penetrated the endosteum, half of their length getting into the haematogenous bone marrow. Seven days after the insertion we collected bone fragments containing the implant. The CT exam revealed a significant decrease in the density of the bone at the interface with the implant and a more discrete one aloof from the insertion area. The histologic exam after 7 days revealed osseous reparatory processes only in the endosteal area from where it expanded on the surface of the implant which was inside the marrow. The presence and intensity of the osseous reparatory processes after only seven days post-implant demonstrates that the marrow actively participates in bone regeneration and implants osseointegration.

RESUMEN: La utilidad de los implantes biomédicos metálicos en afecciones óseas o dentales es irrefutable. El documento tiene como objetivo probar la tolerancia de la médula ósea a los implantes de titanio. Se insertaron implantes de titanio en el fémur de conejos de 11 meses. Los implantes penetraron en el endostio y la mitad de su longitud penetró en la médula ósea hematógena. Siete días después de la inserción, recolectamos fragmentos de hueso que contenían el implante. El examen de TC reveló una disminución significativa en la densidad del hueso en la interfaz con el implante y una más discreta alejada del área de inserción. El examen histológico a los 7 días reveló procesos de reparación ósea solo en el área endóstica desde donde se expandió en la superficie del implante que estaba dentro de la médula. La presencia e intensidad de los procesos de reparación ósea después de solo siete días del implante demuestra que la médula ósea participa activamente en la regeneración ósea y en la osteointegración de los implantes.

Método simplificado para cuantificar el área oseointegrable de implantes dentales / Simplified method to quantify the osseointegration area of dental implants

Introducción: Se han realizado muchas investigaciones sobre los implantes dentales, sin embargo, el área oseointegrable aún es un tema poco tratado en la literatura científica. Objetivo: Diseñar un método para el cálculo del área oseointegrable en la colocación de implantes dentales. Métodos: Las áreas de los implantes se calcularon sobre la base de modelos de implantes de tamaño cuatro veces el real, utilizando las fórmulas conocidas para mantos de cilindro, troncos de cono, círculo (entre otras) y aplicando relaciones lineales para las alturas y para los diámetros al cuadrado (asimilación a teoría de modelos). Se emplearon un calibrador de metales, una lupa y un escalímetro. Los implantes fueron divididos en sectores según su diferente configuración geométrica, la suma de superficies permitió obtener el área total del implante. Las superficies se compararon con el área teórica total de los mismos implantes. Luego se extrapolaron los datos para todos los modelos según sus dimensiones particulares. Resultados: Las áreas obtenidas para implantes tipo tornillo y tipo cónico (diámetro/largo en mm) fueron respectivamente: 3,75/7 = 129 mm2; 3,75/13 = 234 mm2; 3,75/15 = 270 mm2; 4/15 = 306 mm2; 5/7 = 224 mm2 y 3,5/13 = 143 mm2; 4,3/10 = 166 mm2; 4,3/13 = 215 mm2; 4,3/16 = 265 mm2. Conclusiones: La metodología usada en este estudio pareciera ser una buena alternativa para calcular el área final de oseointegración(AU)

Introduction: Many studies have been conducted about dental implants. However, the osseointegration area is a topic not commonly dealt with in the scientific literature. Objective: Design a method to estimate the osseointegration area in the placement of dental implants. Methods: The implant areas were estimated with implant models four times as large as real size, using known formulas for cylinder mantles, cone trunks and circles (among others). Linear relationships were applied for heights and square diameters (assimilation to model theory). Use was made of a metal calibrator, a magnifying glass and a scalimeter. The implants were divided into sectors according to their different geometric configuration. The sum of the surfaces made it possible to obtain the total implant area. The surfaces were compared with the total theoretical area of the same implants. The data were then extrapolated for all the models in keeping with their particular dimensions. Results: The areas obtained for screw and cone implants (diameter / length in mm) were, respectively: 3.75/7 = 129 mm2; 3.75/13 = 234 mm2; 3.75/15 = 270 mm2; 4/15 = 306 mm2; 5/7 = 224 mm2 and 3.5/13 = 143 mm2; 4.3/10 = 166 mm2; 4.3/13 = 215 mm2; 4.3/16 = 265 mm2. Conclusions: The methodology used in the study seems to be a good alternative to estimate the final osseointegration area(AU)

Biomodificación alveolar como un procedimiento indispensable previo a regeneración ósea guiada / Alveolar biomodification as an indispensable procedure before guided bone regeneration

ABSTRACT Introduction: The placement of dental implants is based on the creation of optimal conditions in the remnant bone. In some cases, it is indispensable to perform bone regeneration procedures and use barrier membranes to create such optimal conditions capable of favorably supporting the dental implant. Objective: Describe alternatives of barrier membranes in cases of guided bone regeneration. Case report: A female 53-year-old patient presents with a gingival fistula attached to tooth 14. Root fracture is diagnosed and extraction is conducted. Next, alveolar biomodification is performed to carry out guided bone regeneration and placement of a fibrin-rich plasma membrane. When healing is complete dental implants will be placed. Conclusions: The use of barrier membrane alternatives has shown to be effective in cases of guided bone regeneration(AU)

RESUMEN Introducción: Para la colocación de implantes dentales se deben establecer condiciones óptimas de hueso remanente, por lo cual existen casos en los que se hace indispensable realizar procesos de regeneración ósea y la utilización de membranas de barrera para generar esas condiciones óptimas que puedan soportar favorablemente el implante dental. Objetivo: Describir alternativas de membranas de barrera en casos de regeneración ósea guiada. Reporte de caso: Paciente femenino de 53 años de edad que acude a consulta por presentar fístula en encía adherida de órgano dentario 14, se diagnostica como fractura radicular y se procede a la extracción, posteriormente se realiza una biomodificación del alveolo para realizar regeneración ósea guiada y colocación de membrana de plasma rica en fibrina, se espera cicatrización para la colocación de implantes dentales. Conclusiones: El uso de alternativas de membranas de barrera muestra resultados efectivos en casos de regeneración ósea guiada(AU)

Enhanced osseointegration of porous titanium scaffold implanted with preload: an experiment study in rabbits / Osteointegración mejorada de malla de titanio poroso implantada con precarga: un estudio experimental en conejos

Porous titanium alloy scaffold was widely used in treating bone defect caused by traumatic injury and osteomyelitis, which was incapable of self-healing. The implantation of scaffold produced stress shielding thereby forming osteolysis. The objective of this study was to analysis trabecular morphological features of osseointegrated bone. 14 New Zealand rabbits were divided into two groups, surgery group and healthy control group. 7 rabbits in surgery group were selected to perform 3D printed porous titanium alloy scaffold implantation surgery with preload at the defect of femoral condyle for osseointegration. The other 7 rabbits in control group were feed free. After 90 days healing, femoral condyles were extracted to perform micro-CT scanning with hydroxyapatite calibration phantom. Mean bone mineral density (BMD), bone volume fraction (BV/TV), BS/TV (bone surface area ratio), Tb.Th (thickness of trabeculae), Tb.N (number of trabeculae), Tb.Sp (trabecular separation) and DA (degree of anisotropy) were calculated from micro-CT images. The results revealed that osseointegration inside and at the surface of scaffolds worked well from grey values of micro-CT images. After 12 weeks healing, mean bone mineral densities (BMD) in surgery group and healthy control group were calculated as 800±20mg/cm3 and 980±90mg/cm3, respectively. This revealed that the strength of trabeculae in surgery group might lower than that in the healthy group. Trabecular morphological parameters test showed that trabecular morphological parameters at the surface of scaffolds in the surgery group deteriorated significantly. It was found from micro-CT images that ingrowth bone was filled with pores of scaffold. Overall, the effect of osseointegration was promoted through the change of mechanical micro-environment in the scaffold region. Overall, preload could improve osseointegration effect in the long-term after surgery. However, the trabecular morphology in the surgery group was deteriorated, which might bring secondary fracture risk again.

La malla de aleación de titanio poroso se usó ampliamente en el tratamiento de defectos óseos causados por lesiones traumáticas y osteomielitis. El implante de la malla generó una protección contra el estrés, formando así osteolisis. El objetivo de este estudio fue analizar las características morfológicas trabeculares del hueso osteointegrado. Se dividieron 14 conejos (Neozelandeses) en dos grupos, grupo cirugía y grupo control saludable. Se seleccionaron 7 conejos en el grupo de cirugía para realizar una implantación de mallas de aleación de titanio poroso, impresas en 3D con precarga en el defecto del cóndilo femoral para la osteointegración. Los 7 conejos restantes del grupo control se mantuvieron sin alimentación. Después de 90 días de curación, se extrajeron los cóndilos femorales para realizar una exploración por micro-CT con un espectro de calibración de hidroxiapatita. Se calcularon a partir de imágenes de micro-CTDensidad mineral ósea media (DMO), fracción de volumen óseo (BV / TV), BS / TV (relación de área de superficie ósea), Tb.Th (espesor de trabéculas), Tb.N (número de trabéculas), Tb.Sp (trabecular separación) y DA (grado de anisotropía). Los resultados revelaron que la osteointegración dentro y en la superficie de los andamios funcionó bien a partir de los valores grises de las imágenes de micro-CT. Después de 12 semanas de curación, las densidades medias de minerales óseos (DMO) en el grupo cirugía y en el grupo control sano se calcularon como 800 ± 20 mg/cm3 y 980 ± 90 mg/cm3, respectivamente. Esto reveló que la fuerza de las trabéculas en el grupo de cirugía podría ser menor que la del grupo sano. La prueba de parámetros morfológicos trabeculares mostró que en el grupo de cirugía, la superficie de las mallas, se deterioraron significativamente. Se descubrió a partir de imágenes de microCT que el hueso en crecimiento estaba lleno de poros de andamio. En general, el efecto de la osteointegración se promovió mediante el cambio del microambiente mecánico en la región de la malla. En general, la precarga podría mejorar el efecto de osteointegración a largo plazo después de la cirugía. Sin embargo, la morfología trabecular en el grupo de cirugía se deterioró, lo que podría traer un nuevo riesgo de fractura secundaria.

La técnica del cono de helado, una posibilidad de tratamiento predecible / The ice cream cone technique, a predictable treatment possibility

ABSTRACT Introduction: The volumetric preservation of bone and soft tissue after a tooth extraction has special relevance in the esthetic zone when it will be rehabilitated by a dental implant. Objective: Describe the prosthodontics treatment in a socket with advanced buccal bone resorption, with a flapless technique for guided bone regeneration and with a dental implant and implant-supported single fixed prosthesis. Case presentation: A case is presented of a male 62-year-old partially dentate patient. Radiographic examination showed the presence of advanced buccal bone resorption in relation to the maxillary left lateral incisor. It was a result of the root displacement secondary to root fracture. In a first surgical phase the lateral incisor was extracted using an atraumatic periotome technique. Particulate cortical bone allograft was compacted into the site to fill the space that was previously occupied by the root of the tooth. Temporary restoration was performed using the extracted natural tooth, which was adhesively bonded to the adjacent teeth. Four months after grafting the extraction site showed an adequate height and width of the bone. In a second surgical phase, an implant was placed. Six months after implant placement, osseointegration was clinically confirmed and a provisional crown was screwed on the implant performed. The final restoration with a zirconium dioxide abutment and a full ceramic crown was obtained and cemented. Conclusions: Regeneration of the buccal plate was possible through the use of particulate cortical bone allograft and a resorbable collagen membrane adapted to the bone defect and placed in a position to recreate the buccal plate. This allowed the installation of an implant 4 months later, the procedure allowing esthetic and functional results using a single fixed prosthesis(AU)

RESUMEN Introducción: La preservación volumétrica de los huesos y tejidos blandos después de una extracción dental tiene especial relevancia en la zona estética cuando será rehabilitada por un implante dental. Objetivo: Describir el tratamiento de prótesis en una cavidad con reabsorción ósea bucal avanzada, con una técnica sin colgajo para la regeneración ósea guiada y con un implante dental y una prótesis fija única con soporte de implante. Presentación del caso: Paciente masculino de 62 años, edente parcial. El examen radiográfico mostró la presencia de reabsorción ósea bucal avanzada en relación con el incisivo lateral superior izquierdo. Fue el resultado del desplazamiento de la raíz secundario a la fractura de esta. En una primera fase quirúrgica, el incisivo lateral se extrajo utilizando una técnica de periotoma atraumático. El aloinjerto de hueso cortical particulado se compactó en el sitio para llenar el espacio que anteriormente ocupaba la raíz del diente. La restauración temporal se realizó utilizando el diente natural extraído, que se unió adhesivamente a los dientes adyacentes. Cuatro meses después del injerto, el sitio de extracción mostró una altura y anchura adecuadas del hueso. En una segunda fase quirúrgica, se colocó un implante. Seis meses después de la colocación del implante, se confirmó clínicamente la osteointegración y se realizó una corona provisional atornillada al implante. La restauración final con un pilar de dióxido de circonio y una corona de cerámica completa se obtuvo y se cementó. Conclusiones: La regeneración de la placa bucal fue posible mediante el uso de aloinjerto de hueso cortical particulado y una membrana de colágeno reabsorbible adaptada al defecto óseo y colocada en una posición para recrear la placa bucal. Esto permitió la instalación de un implante 4 meses después. El procedimiento permitió la estética y los resultados funcionales utilizando una única prótesis fija(AU)

Effects of restraint stress and high-fat diet on osseointegration of titanium implants: an experimental study

Abstract This study aimed to investigate the effects of chronic restraint stress (RS) and a high-fat diet (HFD) on the osseointegration of titanium implants in a rat model. After the surgical insertion of titanium implants into the metaphysis of the tibial bone, the rats were randomly divided into four equal groups (n = 8 each): control (CNT), restraint stress (RS), high-fat diet (HFD), and restraint stress plus high fat diet (RS-HFD). CNT: Rats received no further treatment during the 92-day experimental period. RS: Stress was applied to the rats beginning from two days after the implant surgery for one hour per day for the first 30 days, two hours per day for the next 30 days, and three hours per day for the last 30 days. HFD: Rats were fed a HFD for the following 90 days starting two days after surgery. RS-HFD: Rats were fed a HFD and RS was applied to rats for the following 90 days, starting two days after surgery. At the end of the experimental period, the rats were euthanized, and the implants and surrounding bone tissues were removed for histological analysis. Statistical analysis was performed by one way ANOVA and Bonferrroni tests. There were no significant differences in the bone-implant connection levels between the groups (p > 0.05), but in the HFD and RS-HFD groups, the bone filling ratios were found to be lower compared with the controls (p < 0.05) The data analyzed in this study suggest that an HFD with or without chronic RS adversely affected bone tissue in the rats during the 90-day osseointegration period.

Effects of restraint stress and high-fat diet on osseointegration of titanium implants: an experimental study

Abstract This study aimed to investigate the effects of chronic restraint stress (RS) and a high-fat diet (HFD) on the osseointegration of titanium implants in a rat model. After the surgical insertion of titanium implants into the metaphysis of the tibial bone, the rats were randomly divided into four equal groups (n = 8 each): control (CNT), restraint stress (RS), high-fat diet (HFD), and restraint stress plus high fat diet (RS-HFD). CNT: Rats received no further treatment during the 92-day experimental period. RS: Stress was applied to the rats beginning from two days after the implant surgery for one hour per day for the first 30 days, two hours per day for the next 30 days, and three hours per day for the last 30 days. HFD: Rats were fed a HFD for the following 90 days starting two days after surgery. RS-HFD: Rats were fed a HFD and RS was applied to rats for the following 90 days, starting two days after surgery. At the end of the experimental period, the rats were euthanized, and the implants and surrounding bone tissues were removed for histological analysis. Statistical analysis was performed by one way ANOVA and Bonferrroni tests. There were no significant differences in the bone-implant connection levels between the groups (p > 0.05), but in the HFD and RS-HFD groups, the bone filling ratios were found to be lower compared with the controls (p < 0.05) The data analyzed in this study suggest that an HFD with or without chronic RS adversely affected bone tissue in the rats during the 90-day osseointegration period.

The Influence of Dietary Salt on the Osseointegration of Implants in Aging Rats

Introduction: The bone-implant interface has been studied extensively, but only few papers focused on the nutritional aspects that may affect bone quality, especially salt intake. Objective: To study the osseointegration of implants in salt-loaded rats with low mineral bone content. Methods: A total of 60 4-month-old male rats were divided in 2 groups ( n = 30), being these groups divided in 2 periods, (2 and 4 months). The control group received a normal diet, while the test group received a diet supplemented with 1% sodium chloride (NaCl). Implants were placed in the tibia of both groups. A total of 15 animals of each group were sacrificed at the 2 nd month of the experiment, while the remaining animals were sacrificed at the 4 th month. Results: No statistically significant difference was found in food intake between the groups on any experimental period, but a statistically significant difference was found in the liquid intake in the saline group in both periods. For all groups, osseointegration was observed in both groups. The mean percentage of osseointegration in the cortical bone, in the trabecular bone, and in the total osseointegrated surface between the control (46.38 ± 16.17%) and saline (49.13 ± 11.52%) groups at 2 months was not statistically different ( p = 0.61). The total osseointegration areas of the control (53.98 ± 12.06%) and saline (51.40 ± 13.01%) groups at the 4 th month of the study were not statistically ( p = 0.61). Conclusion: Ingestion of salt did not affect directly the osseointegration process during the period of the experiment. The results suggest that mineral losses may not affect the achievement of good osseointegration in aging rats. (AU)

Reparación atípica de alveolo en rehabilitación estética implantológica / Atypical socket repair in aesthetic implant rehabilitation

ABSTRACT Introduction: In implant therapy, adequate alveolar bone volume and favorable alveolar ridge architecture are important considerations to obtain positive functional and esthetic rehabilitation. Objective: Describe prosthodontic treatment in an extraction socket with advanced palatal bone resorption secondary to a root fracture through the use of an implant-supported single fixed prosthesis. Principal case data: 39-year-old male patient, without systemic disease, and completely dentate with no occlusal parafunction. Radiographic examination showed the presence of advanced palatal bone resorption, almost total loss of the palatal plate in all its extension secondary to a root fracture of the maxillary left lateral incisor and a large osteolytic area on the palatal aspect of the root. The procedure consisted in extraction of the maxillary left lateral incisor and eventual regeneration of the palatal plate using a resorbable collagen membrane, which was adapted to the bone defect. Then, particulate cortical bone allograft was compacted into the site. Four months after grafting the extraction site, an implant was placed. Six months after implant placement osseointegration was confirmed, and after several stages restoration with a zirconium dioxide abutment and a full ceramic crown was obtained and followed up for 2 years. Conclusions: Regeneration of the palatal plate was possible through the use of particulate cortical bone allograft and a resorbable collagen membrane adapted to the bone defect and placed in position to recreate the palatal plate. This allowed installation of an implant 4 months after the procedure. This technique allowed esthetic and functional results using a single fixed prosthesis(AU)

RESUMEN Introducción: Para la terapia con implantes, un volumen adecuado de hueso alveolar y una arquitectura favorable de la cresta alveolar son consideraciones importantes para obtener una rehabilitación funcional y estética positiva. Objetivo: Describir el tratamiento protésico en una cavidad de extracción con reabsorción ósea palatina avanzada secundaria a una fractura de la raíz, mediante el uso de una prótesis fija única con soporte de implante. Datos principales del caso: Paciente masculino de 39 años, sin enfermedad sistémica, completamente dentado sin parafunción oclusal. El examen radiográfico mostró la presencia de una reabsorción ósea palatina avanzada, una pérdida casi total de la placa palatina en toda su extensión secundaria a una fractura de la raíz del incisivo lateral superior izquierdo y una gran área osteolítica en el aspecto palatino de la raíz. El procedimiento consistió en la extracción del incisivo lateral superior izquierdo y la regeneración posterior de la placa palatina mediante una membrana de colágeno reabsorbible, que se adaptó al defecto óseo. Luego, el aloinjerto de hueso cortical particulado se compactó en el sitio. Cuatro meses después de injertar el sitio de extracción, se colocó un implante. Seis meses después de la colocación del implante, se confirmó la osteointegración y, después de varias etapas, se obtuvo una restauración con un pilar de dióxido de circonio y una corona de cerámica completa, la que fue seguida durante dos años. Conclusiones: La regeneración de la placa palatina fue posible mediante el uso de aloinjerto de hueso cortical particulado y una membrana de colágeno reabsorbible adaptada al defecto óseo y colocada en una posición para recrear la placa palatina. Esto permitió la instalación de un implante 4 meses después del procedimiento. Con esta técnica se obtuvieron resultados funcionales y estéticos utilizando una única prótesis fija(AU)

Causas y complicaciones de los fracasos de la implantología dental. Matanzas / Causes and consequences of failures of the dental implantology. Matanzas

Introducción: Los implantes son fijaciones de titanio puro que se colocan en el hueso maxilar o mandibular con el fin de sustituir las raíces de los dientes perdidos, lo cual permite reemplazar el diente natural por uno artificial de mejor funcionalidad pero a pesar de ser una cirugía programada no está exenta de fracasos y las complicaciones se presentan en cualquiera de las fases del tratamiento implantológico. Objetivo: Determinar las causas y complicaciones del fracaso de este tratamiento en la Clínica Estomatológica Docente de Especialidades 3er Congreso del PCC en el periodo de Enero 2010 hasta diciembre 2016. Materiales y métodos: Se realizó una investigación observacional, descriptiva, retrospectiva donde se revisaron 500 Historias Clínicas de pacientes rehabilitados con implantes dentales, el universo lo conformó la totalidad de implantes que fracasaron en el tratamiento por diversas causas o complicaciones (32), en la CEDE Tercer Congreso del PCC del Municipio de Matanzas, en el periodo de Enero 2010 hasta diciembre 2016. Resultados: La mayoría de los fracasos de implantes ocurrió en los pacientes de 35 a 65 años y sexo masculino. En el 53,1 % de los fracasos, la motivación de los pacientes fue por la estética, la mayoría de los fracasos se asociaron a la no oseointegración y a la perimplantitis ocurridos en la fase inicial del tratamiento (62,5%). Conclusiones: Las cifras de fracasos en el tratamiento de implantologia dental en todas las regiones anatómicas de la cavidad bucal fueron bajas y la tasa de supervivencia y éxitos fue alta (AU).

Introduction: theimplants are pure titanium fixations located in the maxillary or mandibular bone with the aim of taking the place of lost teeth roots. They allow to replace the natural tooth for an artificial one with better functioning. Although it is a programmed surgery, it is not free of failures, and complications may appear in any stage of the implantation treatment. Objective: to determine the causes and complications of these treatment failure in the Teaching Dental Clinic "Tercer Congreso del PCC", municipality of Matanzas, in the period from January 2010 to December 2016. Materials and methods: a retrospective, descriptive, observational research was carried out, where 500 clinical records of patients rehabilitated with dental implants were reviewed; the universe was formed by the total of the implants that failed in the treatment due to different causes and complications (32) in the clinic "Tercer Congreso del PCC". Results: most of the implant failures occurred in male patients aged 35-65 year. 53.1 % of the failures were due to the patients' motivation for esthetics; most of the failures were associated to no osseointegration and to perimplantitis occurred in the initial stage of the treatment (62.5 %). Conclusions: the figures of failures in dental implantology treatment were low in all of the anatomic regions of the oral cavity, and the rate of survival and success was high (AU).

Decoronation followed by dental implants placement: fundamentals, applications and explanations

ABSTRACT Dental arches areas with teeth presenting dentoalveolar ankylosis and replacement root resorption can be considered as presenting normal bone, in full physiological remodeling process; and osseointegrated implants can be successfully placed. Bone remodeling will promote osseointegration, regardless of presenting ankylosis and/or replacement root resorption. After 1 to 10 years, all dental tissues will have been replaced by bone. The site, angulation and ideal positioning in the space to place the implant should be dictated exclusively by the clinical convenience, associated with previous planning. One of the advantages of decoronation followed by dental implants placement in ankylosed teeth with replacement resorption is the maintenance of bone volume in the region, both vertical and horizontal. If possible, the buccal part of the root, even if thin, should be preserved in the preparation of the cavity for the implant, as this will maintain gingival tissues looking fully normal for long periods. In the selection of cases for decoronation, the absence of microbial contamination in the region - represented by chronic periapical lesions, presence of fistula, old unconsolidated root fractures and active advanced periodontal disease - is important. Such situations are contraindications to decoronation. However, the occurrence of dentoalveolar ankylosis and replacement resorption without contamination should neither change the planning for implant installation, nor the criteria for choosing the type and brand of dental implant to be used. Failure to decoronate and use dental implants has never been reported.

RESUMO Áreas dos maxilares com dentes em anquilose alveolodentária e reabsorção dentária por substituição podem ser consideradas como portadoras de osso normal, em pleno processo fisiológico contínuo de remodelação; e os implantes osseointegráveis podem ser aplicados com sucesso. A remodelação óssea promoverá sua osseointegração, independentemente de haver raízes em anquilose e/ou em reabsorção por substituição. Após 1 a 10 anos, todos os tecidos dentários terão sido substituídos por osso. O local, a angulação e o posicionamento ideal no espaço para se colocar o implante devem ser ditados pela conveniência clínica associada, exclusivamente, ao planejamento prévio. Uma das vantagens da decoronação com colocação imediata de implantes em dentes anquilosados e com reabsorção por substituição é a manutenção do volume ósseo na região, tanto vertical quanto horizontalmente. Se possível, deve-se preservar, na preparação da cavidade para o implante, a parte vestibular da raiz, mesmo que fina; isso deixará os tecidos gengivais com aspecto de plena normalidade por longos períodos. O importante na seleção de casos para a decoronação é a ausência de contaminação microbiana na região, representada por lesões periapicais crônicas, presença de fístula, fraturas radiculares antigas não consolidadas e doença periodontal avançada ativa. Essas situações são contraindicações para a decoronação. A ocorrência de anquilose alveolodentária e reabsorção por substituição sem contaminação não deve mudar o planejamento para instalação de implantes, nem mesmo os critérios de escolha do tipo e marca de implante dentário a ser utilizado. Nunca foi relatado fracasso na decoronação e uso de implantes dentários.

Stability and bone loss around submerged and non-submerged implants in diabetic and non-diabetic patients: a 7-year follow-up

Abstract To evaluate peri-implant bone loss (PIBL) and stability around submerged and non-submerged dental implants in patients with and without type 2 diabetes mellitus (T2DM). Thirty-five T2DM and non-diabetic (NT2DM) patients were included in this study. Demographic data were recorded using a questionnaire and PIBL was measured on digital radiographs. Resonance frequency analysis (RFA) was carried out for each implant at the time of fixture placement and at 3 months in both groups. P values less than 0.05 were considered statistically significant. One hundred and eighteen dental implants with a mean height of 10 to 12 mm and 3.3 to 4.1 mm in diameter were placed. The comparison of the mean RFA values at baseline and at 3 months was statistically significant (p = 0.008) in T2DM patients. The inter-group mean RFA values at baseline and at 3 months were not significant (p > 0.05). PIBL was significantly high in T2DM as compared to NT2DM patients at each follow-up (p < 0.05). At 2, 3, and 7 years, non-submerged dental implants showed significantly high PIBL in T2DM patients as compared to NT2DM individuals (p<0.05). The results of the present clinical study demonstrate increased PIBL around non-submerged single-tooth implant-supported restorations in T2DM patients, which may be due to the immune inflammatory status.

Can implant surfaces affect implant stability during osseointegration? A randomized clinical trial

Abstract This randomized clinical trial evaluated the insertion torque (IT), primary, and secondary stability of dental implants with different surface treatments during the osseointegration period. Nineteen patients with bilateral partial edentulism in the posterior mandibular region were randomly allocated to two implant brand groups and received implants with different surface treatments in the opposite site of the arch: Osseotite and Nanotite or SLA and SLActive. During implant placement, the maximum IT was recorded using a surgical motor equipped with a graphical user interface. The implant stability quotient (ISQ) was assessed immediately after the IT, and was measured weekly via resonance frequency analysis during 3 months. The data were analyzed by a one-way ANOVA, the Bonferroni test, paired t tests and Pearson's correlation coefficient. The IT values were similar (p > 0.05) for all implant types ranging from 43.82 ± 6.50 to 46.84 ± 5.06. All implant types behaved similarly until the 28th day (p > 0.05). Between 35 and 56 days, Osseotite and SLActive showed lower ISQ values (p < 0.001) compared to Nanotite and SLA implants. After 56 days, only Osseotite maintained significantly lower ISQ values than the other implants (p < 0.05). After 91 days the ISQ values were significantly higher than the baseline for all four implant types (p < 0.001). The ISQ and IT values were significantly correlated at the baseline and at the final evaluation for Osseotite, Nanotite, and SLActive implants (p < 0.001). After 91 days, ISQ and IT values were only significantly correlated for the Osseotite implants (p < 0.05). All implants types exhibited acceptable primary and secondary stability.

Oral implant osseointegration model in C57Bl/6 mice: microtomographic, histological, histomorphometric and molecular characterization

Abstract Despite the successful clinical application of titanium (Ti) as a biomaterial, the exact cellular and molecular mechanisms responsible for Ti osseointegration remains unclear, especially because of the limited methodological tools available in this field. Objective: In this study, we present a microscopic and molecular characterization of an oral implant osseointegration model using C57Bl/6 mice. Material and Methods: Forty-eight male wild-type mice received a Ti implant on the edentulous alveolar crest and the peri-implant sites were evaluated through microscopic (μCT, histological and birefringence) and molecular (RealTimePCRarray) analysis in different points in time after surgery (3, 7, 14 and 21 days). Results: The early stages of osseointegration were marked by an increased expression of growth factors and MSC markers. Subsequently, a provisional granulation tissue was formed, with high expression of VEGFb and earlier osteogenic markers (BMPs, ALP and Runx2). The immune/inflammatory phase was evidenced by an increased density of inflammatory cells, and high expression of cytokines (TNF, IL6, IL1) chemokines (CXCL3, CCL2, CCL5 and CXC3CL1) and chemokine receptors (CCR2 and CCR5). Also, iNOS expression remained low, while ARG1 was upregulated, indicating predominance of a M2-type response. At later points in time, the bone matrix density and volume were increased, in agreement with a high expression of Col1a1 and Col21a2. The remodelling process was marked by peaks of MMPs, RANKL and OPG expression at 14 days, and an increased density of osteoclasts. At 21 days, intimate Ti/bone contact was observed, with expression of final osteoblast differentiation markers (PHEX, SOST), as well as red spectrum collagen fibers. Conclusions: This study demonstrated a unique molecular view of oral osseointegration kinetics in C57Bl/6 mice, evidencing potential elements responsible for orchestrating cell migration, proliferation, ECM deposition and maturation, angiogenesis, bone formation and remodeling at the bone-implant interface in parallel with a novel microscopic analysis.

Effects of hyperbaric oxygen treatment on implant osseointegration in experimental diabetes mellitus

Abstract Objective To evaluate whether hyperbaric oxygen (HBO) treatment has a favorable effect on implant osseointegration in diabetic rabbits. Material and Methods An experimental diabetes model was induced in 32 New Zealand rabbits through IV injection of alloxan. After the state of diabetes had been confirmed, one dental implant was placed in the metaphysical region of each animal's tibia. After the implants' placements, the animals were divided into two groups. Half of the animals underwent HBO treatment, while the other group did not receive HBO treatment and served as the control group. The animals were euthanized at the 4th and 8th weeks. The osseointegration of the implants were compared by histomorphometry and resonance frequency analysis (RFA). Results The Bone Implant Contact (BIC) values were significantly higher in the HBO group than in the control group at the 4th week. There was no difference in the BIC values between the groups at the 8th week. There was no significant difference in the RFA scores between the groups both at the 4th and 8th weeks after the operation. Conclusion Histomorphometry findings suggest that HBO has positive effect on implant osseointegration in the early healing period in diabetic rabbits. However, implant stability is not affected by HBO treatment.

Fracaso implantario derivado de la práctica del submarinismo: a propósito de un caso / Implant failure secondary to Scuba diving: report of a case

En las últimas décadas, el buceo con equipo de respiración subacuático autónomo (SCUBA) ha experimentado un gran auge, lo que conlleva la necesidad por parte del odontólogo de conocer las posibles complicacionesasociadas. Durante su práctica, se producen cambios en la presión inducida, así como micromovimientos derivados de sostener la boquilla del tubo de oxígeno con la boca, que pueden conducir al fracaso temprano del implante. El tiempo mínimo recomendado antes de volvera practicar el submarinismo tras la inserción de implantes dentales depende del criterio del cirujano; sin embargo, no se recomienda que seaantes de las primeras cinco semanas a dos meses postquirúrgicos. Encirugías con procedimientos asociados más complejos, se recomiendan periodos de reposo más largos.

In the last decades, the number of people who practice self-contained underwater breathing apparatus (SCUBA) diving has increased,which makes it important for dentists to be prepared to address andtreat complications resulting from its practice. While performing the sport, pressure may change and induced micro-motion derived from holding the tube of oxygen can lead to an early implant failure. Divingis not recommended during the fi rst fi ve weeks to two months after the implant placement. In surgeries where the associated procedures aremore complex, a greater recovery period is recommended.

Implantes cortos como alternativa terapéutica actual en el tratamiento de maxilares atróficos / Short implants as current therapeutic alternatives to the treatment of athrophic jaws

La variación en el volumen óseo producida tras la pérdida dental, hace que el tratamiento de los pacientesque presentan atrofias avanzadas en los maxilares sea un desafío para todo cirujano. En la actualidad, el uso de implantes dentales para reemplazar piezas dentarias perdidas es una opción de tratamiento. El tratamiento con implantes cortos se comporta tanpredecible como el uso de implantes convencionales, pero estos resultados siguen siendo objeto de controversia. Los implantes cortos tienen tasas de éxito similares a las de los implantes de longitud estándar, pueden ser utilizados como alternativa en el tratamiento de maxilares atróficos, siempre que sean manejadosbajo una cuidadosa planificación de tratamiento. El objetivo del presente trabajo es exponer una revisiónde la literatura actual sobre el uso de implantes cortos como alternativa de tratamiento terapéutico en presencia de maxilares atróficos.

The variation in the bone volume produced afterdental loss makes the treatment of patientswith advanced atrophies in the jaws a challengefor every surgeon. At present, the use of dental implants to replace lost teeth is a treatment option.Treatment with short implants behaves aspredictably as the use of conventional implants,but these results remain controversial. Short implants have similar success rates to thoseof standard length implants and can be usedas an alternative in the treatment of atrophic jaws, provided they are handled under careful treatment planning.The aim of the present study is to presenta review of the current literature on the use of short implants as an alternative therapeutic treatment in the presence of atrophic jaws.

Effects of continual intermittent administration of parathyroid hormone on implant stability in the presence of osteoporosis: an in vivo study using resonance frequency analysis in a rabbit model

Abstract Objective: This study aimed to evaluate the effects of continual intermittent administration of parathyroid hormone (PTH) on implant stability in the presence of osteoporosis, using rabbit models. Material and Methods: Fifteen female New Zealand white rabbits underwent ovariectomy and were administered glucocorticoids to induce osteoporosis, following which they were divided into three groups. The first group received intermittent subcutaneous PTH for 4 weeks until implant placement (PTH1), while the second and third groups received PTH (PTH2) and saline (control), respectively, for 4 weeks before and after implant placement. After intermittent administration of PTH or saline, titanium implants were inserted into the left femoral epiphyses of all animals, and the implant stability quotient (ISQ) was measured immediately after placement to assess the primary stability and at 2 and 4 weeks after implant placement to assess osseointegration. At 4 weeks after implant placement, histological and histomorphometric evaluations were conducted and the bone area around the implant socket was measured as a ratio of the total bone area to the total tissue area. Results: Regarding primary stability, the ISQ values for the PTH1 and PTH2 groups were significantly higher than those for the control group (p<0.05). Concerning osseointegration, the ISQ values at 2 and 4 weeks were significantly higher for the PTH2 group than for the PTH1 and control (p<0.05) groups. Histological assessments showed a thicker and more trabecular bone around the implant sockets in the PTH2 specimens than in the PTH1 and control specimens. The bone area around the implant socket was significantly greater in the PTH2 group than in the PTH1 and control groups (p<0.05). Conclusions: Our results suggest that continual intermittent PTH administration before and after dental implant placement is effective for the achievement of favorable stability and osseointegration in the presence of osteoporosis.

Osteointegration of porous absorbable bone substitutes: A systematic review of the literature

Biomaterials' structural characteristics and the addition of osteoinductors influence the osteointegration capacity of bone substitutes. This study aims to identify the characteristics of porous and resorbable bone substitutes that influence new bone formation. An Internet search for studies reporting new bone formation rates in bone defects filled with porous and resorbable substitutes was performed in duplicate using the PubMed, Web of Science, Scielo, and University of São Paulo Digital Library databases. Metaphyseal or calvarial bone defects 4 to 10 mm in diameter from various animal models were selected. New bone formation rates were collected from the histomorphometry or micro-CT data. The following variables were analyzed: animal model, bone region, defect diameter, follow-up time after implantation, basic substitute material, osteoinductor addition, pore size and porosity. Of 3,266 initially identified articles, 15 articles describing 32 experimental groups met the inclusion criteria. There were no differences between the groups in the experimental model characteristics, except for the follow-up time, which showed a very weak to moderate correlation with the rate of new bone formation. In terms of the biomaterial and structural characteristics, only porosity showed a significant influence on the rate of new bone formation. Higher porosity is related to higher new bone formation rates. The influence of other characteristics could not be identified, possibly due to the large variety of experimental models and methodologies used to estimate new bone formation rates. We suggest the inclusion of standard control groups in future experimental studies to compare biomaterials.