Neo-osteogenesis using an intentionally exposed polypropylene membrane after tooth extraction versus guided bone regeneration technique: a single-blind randomized controlled trial / Neo-osteogénesis utilizando una membrana de polipropileno expuesta intencionalmente después de la extracción del diente versus técnica de regeneración ósea guiada: ensayo clínico aleatorizado ciego / Neo-osteogênese utilizando uma membrana de polipropileno exposta intencionalmente após extração dentária versus técnica de regeneração óssea guiada: ensaio clínico randomizado e cego

Introduction: The intentionally exposed polypropylene (PP) membrane has been proposed for guided bone regeneration (GBR) of the alveo lar bone after extraction; however, there are biological limitations to this proposal. This study aimed to describe the effects of the PP membrane on neo-osteogenesis after tooth extraction, comparing to intentionally ex posed and primary soft tissue coverage techniques. Methodology: This clinical trial followed the TIDieR checklist and guide. Clinical and histo logical parameters of alveolar repair were compared between groups: 1 (control group), without regenerative procedure; 2, GBR; and 3, inten tionally exposed membrane. Results: Group 3 showed slight effect on the quality of new bone, compared to the control group. Although the GBR was underestimated by the early exposure of the membrane, alveo lar repair and newly formed bone were superior to the other groups. Poly propylene membrane intentionally exposed compromised the volume density of the immature and mineralized bone matrix, the osteoblast and osteocyte count, and stimulated the granulation tissue formation and local inflammatory infiltrate. Conclusions: Despite the exposure of the PP membrane in GBR, this technique improved the quality of new bone and alveolar repair compared to the surgical technique of intentional exposure and alveolus only sutured.

RESUMEN Introducción: La membrana de polipropileno (PP) intencionalmente expuesta ha sido propuesta para la regeneración ósea guiada (GBR) del hueso alveolar después de la extracción; sin embargo, existen limitaciones biológicas a esta propuesta. Este estudio tuvo como objetivo describir los efectos de la membrana de PP en la neo-osteogénesis después de la extracción del diente, en comparación con las técnicas de cobertura de tejido blando primarias y expuestas intencionalmente. Metodología: Este ensayo clínico siguió la lista de verificación y la guía TIDieR. Se compararon los parámetros clínicos e histológicos de la reparación alveolar entre los grupos: 1 (grupo control), sin procedimiento regenerativo; 2, GBR; y 3, membrana expuesta intencionalmente. Resultados: el grupo 3 mostró un ligero efecto sobre la calidad del hueso nuevo, en comparación con el grupo de control. Aunque la GBR fue subestimada por la exposición temprana de la membrana, la reparación alveolar y el hueso neoformado fueron superiores a los otros grupos. La membrana de polipropileno expuesta intencionalmente comprometió la densidad de volumen de la matriz ósea inmadura y mineralizada, el recuento de osteoblastos y osteocitos, y estimuló la formación de tejido de granulación y el infiltrado inflamatorio local. Conclusiones: A pesar de la exposición de la membrana de PP en GBR, esta técnica mejoró la calidad del hueso nuevo y la reparación alveolar en comparación con la técnica quirúrgica de exposición intencional y alvéolo solo suturado.

Introdução: A membrana de polipropileno (PP) intencionalmente exposta tem sido proposta para regeneração óssea guiada (ROG) do osso alveolar após exodontia; no entanto, existem limitações biológicas a esta proposta. Este estudo teve como objetivo descrever os efeitos da membrana de PP na neo-osteogênese após a extração dentária, comparando com as técnicas de exposição intencional e cobertura primária de tecidos moles. Metodologia: Este ensaio clínico seguiu a lista de verificação e o guia TIDieR. Parâmetros clínicos e histológicos do reparo alveolar foram comparados entre os grupos: 1 (grupo controle), sem procedimento regenerativo; 2, GBR; e 3, membrana intencionalmente exposta. Resultados: O Grupo 3 apresentou leve efeito na qualidade do novo osso, em comparação com o grupo controle. Embora o GBR tenha sido subestimado pela exposição precoce da membrana, o reparo alveolar e o osso neoformado foram superiores aos outros grupos. A exposição intencional da membrana de polipropileno comprometeu a densidade volumétrica da matriz óssea imatura e mineralizada, a contagem de osteoblastos e osteócitos e estimulou a formação de tecido de granulação e infiltrado inflamatório local. Conclusões: Apesar da exposição da membrana PP na ROG, esta técnica melhorou a qualidade do novo osso e da reparação alveolar em comparação com a técnica cirúrgica de exposição intencional e alvéolo apenas suturado.

Aumento do Rebordo Alveolar com Enxerto em Bloco Impresso Personalizado: Relato de Caso / Alveolar ridge augmentation with custom 3D-printed block graft: Case report

A utilização da tecnologia CAD/CAM (computer aided design/computer aided manufacturing) e 3D (tridimensional) para reconstruções alveolares na implantodontia permite o planejamento pré-operatório detalhado, o design do resultado desejado do enxerto e a avaliação virtual do resultado em relação à reconstrução protética. Este trabalho objetiva detalhar a técnica cirúrgica de enxerto ósseo sintético confeccionado por meio dessa tecnologia, seguido da instalação de implantes osseointegráveis e reabilitação protética em um defeito ósseo na mandíbula. Paciente masculino, 22 anos, compareceu à clínica por avulsão dos elementos 32, 31, 41 e 42 com significativa perda óssea vertical de rebordo alveolar. Devido à extensa perda óssea, realizou-se enxerto em bloco prototipado impresso. O escaneamento intraoral e os arquivos de imagem gerados foram enviados ao centro de planejamento virtual. Primeiramente, foi realizada a cirurgia para instalação do enxerto em bloco. Após o período de cicatrização, foi realizada cirurgia para instalação de dois implantes osseointegráveis. Esperado o período de três meses a partir da instalação dos implantes, foi realizada a confecção de próteses provisórias fixas sobre implantes a fim de realizar o condicionamento dos tecidos moles peri-implantares e o carregamento progressivo dos implantes. O aumento do rebordo alveolar através do uso de enxerto em bloco impresso personalizado apresentou-se como uma técnica com inúmeras vantagens, por não necessitar de sítio doador, reduzir tempo cirúrgico e apresentar perfeita adaptação do bloco ao defeito ósseo, resultando em menor morbidade pós-operatória. Essa técnica é uma indicação para casos de defeitos ósseos severos, visando a otimizar o resultado e a propiciar menor desconforto ao paciente.

The use of the technology CAD/CAM (computer aided design/computer aided manufacturing) and 3D (three dimensional) to alveolar reconstructions in implant dentistry allows detailed preoperative planning, the design of the desired grafting result, and the virtual evaluation of the result in relation to the prosthetic reconstruction. This paper aims to details the synthetic bone graft made through this technology, followed by the installation of osseointegrated implants and prosthetic rehabilitation in a bone imperfection in the jaw. A 22-year-old man attended the clinic due to a tooth avulsion of the four lower incisors with significant vertical bone loss of alveolar ridge. Because of the extensive bone loss, it was made a prototyped printed block graft. The intraoral scan and the generated image files were sent to the virtual planning center. First, it was necessary a surgery to install the block graft. After the healing process, it was made a surgery to put two osseointegrated implants. Three months later, temporary fixed prostheses on implants were made to conditioning the peri-implant soft tissues and the progressive loading of the implants. The increase of the alveolar ridge using personalized printed block graft was presented as a technique with numerous advantages, since it does not require a donor site, reduces the surgical time and presents perfect adaptation of the block to the bone imperfection, resulting in a less postoperative morbidity. This technique is indicated to cases of severe bone imperfections, aims to optimize results, and provide less discomfort to the patient.

Regeneração óssea guiada para aumento horizontal de rebordo utilizando fibrina rica em plaquetas associada a enxertos ósseos: revisão de literatura / Guided bone regenerationfor horizontal bone augmentation using platelet- rich fibrin associated with bone grafts: literature review

Objetivo: revisar a literatura sobre os diferentes tipos de derivados de plaquetas autólogas e o desempenho clínico do uso do sticky bone para aumento ósseo horizontal de rebordo. Materiais e métodos: Para realização dessa revisão foram realizadas buscas nas bases de dados PubMed, Google Scholar e Web of Science, utilizando os seguintes descritores: "platelet-rich fibrin" AND "sticky bone" OR "alveolar bone grafting" AND "sticky bone" OR "guided bone regeneration" AND "sticky bone" AND "alveolar ridge augmentation" OR "Alveolar ridge augmentation" AND "sticky bone". Foram incluídos artigos publicados em inglês, que abordavam conceitos relacionados aos agregados plaquetários e a regeneração óssea guiada para aumento ósseo horizontal de rebordo utilizando fibrina rica em plaquetas associada à enxertos ósseos (sticky bone). Resultados: Após avaliação dos estudos encontrados foram selecionados 11 artigos sobre o uso do sticky bone para aumento horizontal de rebordo. Para compor este trabalho foram selecionados também 14 estudos de revisão e artigos associados ao tema. Por ser de fácil aplicação e obtenção, muitos autores têm estudado as aplicações cirúrgicas do sticky bone e os resultados demonstram que o aumento horizontal do rebordo utilizando essa técnica pode ser realizado de forma previsível. Conclusão: apesar de haver estudos promissores sobre o uso do sticky bone, falta evidência na literatura sobre seu sucesso clínico. Assim, para compreender o potencial regenerativo desta técnica são necessários um maior número de estudos randomizados, com diferentes materiais de enxerto e protocolos padronizados de obtenção do sticky bone.(AU)

Objective: to review the literature on the different types of autologous platelet derivatives and the clinical performance of using sticky bone for horizontal bone ridge augmentation. Materials and methods: In order to conduct this review, it was conducted searches in the PubMed, Google Scholar, and Web of Science databases using the following descriptors: "platelet-rich fibrin" AND "sticky bone" OR "alveolar bone grafting" AND "sticky bone" OR "guided bone regeneration" AND "sticky bone" AND "alveolar ridge augmentation" OR "Alveolar ridge augmentation" AND "sticky bone". It included articles published in English that addressed concepts related to platelet aggregates and guided bone regeneration for horizontal bone augmentation using platelet-rich fibrin associated with bone grafts (sticky bone). Results: After evaluating the studies found, were selected 11 articles on the use of sticky bone for horizontal ridge augmentation. To compose this work, 14 review studies and articles associated with the topic were also selected. Due to its ease of application and availability, many authors have explored the surgical applications of sticky bone, and the results indicate that horizontal ridge augmentation using this technique can be predictably performed. Conclusion: while there are promising studies on the use of sticky bone, the literature lacks evidence regarding its clinical success. Therefore, to fully understand the regenerative potential of this technique, further randomized studies are needed, involving different graft materials and standardized protocols for obtaining sticky bone.(AU)

Key points to execute internal horizontal mattress suture in tissue augmentation / 口腔疾病防治

@#Ideal sutures can provide great fixation, wound closure and a stable environment for healing of the surgical site. Tension-free apposition sutures are important for tissue regeneration and could tackle insufficient amounts of soft and hard tissue, especially in missing tooth sites that require implantation. The internal horizontal mattress suture, similar to the conventional horizontal mattress suture, forms a rectangle that can be bisected by the incision with both intrusion and extrusion of the needle on each side. On the basis of the rectangle, the internal horizontal mattress suture emphasizes that the suture should be located below the incision, so the eversion of the wound margin is the highlight of this procedure. The internal horizontal mattress suture could stabilize the graft on the targeting tissue, realize the fixation of the collagen membrane, apically repositioned flap and soft tissue graft, reduce the tension on the incision, and further release the tension of the incision margin. Beyond the primary need for fixation and wound closure, internal horizontal mattress sutures can also achieve stress interruption that reduces the interference of the surrounding muscle and can better master wound tension with the assistance of interrupted sutures. Given the above advantages, horizontal internal mattress sutures have great potential in the application of implant-related regenerative surgery. In this review, according to our experience in clinical practice and the literature, we summarize the advantages of internal horizontal mattress sutures in tissue augmentation. In addition, the sites and sequence to insert the needle and the spatial relationship between the suture and incision are clarified with the rationale of the naming pattern, which is conducive to experience exchange and clinical practice.

Preservação alveolar e instalação tardia de implante dentário: relato de caso / Alveolar preservation and late dental implant installation: case report / Preservación alveolar e instalación tardía de implante dental: reporte de caso

Introdução. Decorrente do trauma local, durante a exodontia, ou pela falta de estímulos mastigatórios, a ausência dentária promove respostas biológicas que desencadeiam um processo de reabsorção óssea. A preservação óssea alveolar propõe minimizar a reabsorção óssea alveolar, promovendo maior biodisponibilidade óssea para a reabilitação por implantes dentários. Os implantes dentários são uma modalidade terapêutica eficaz para a reabilitação de ausências dentárias. Objetivo. relatar um caso de reabilitação por implante em alvéolo cicatrizado, após preservação alveolar. Relato de caso. Paciente A.L.L., sexo masculino, 23 anos, compareceu à clínica odontológica da UNIBRA. Ao exame físico observou-se ampla destruição coronária do elemento 25 e, ao exame radiográfico notou-se tratamento endodôntico. O tratamento proposto foi a exodontia minimamente traumática, preservação alveolar com matriz de colágeno e instalação de implante dentário em alvéolo cicatrizado. Discussão. Em desdentados, a falta de estímulos mastigatórios, promove um desequilíbrio no turnover ósseo, desencadeando um processo de reabsorção. A preservação alveolar por matriz de colágeno visa minimizar a reabsorção e fornecer maior biodisponibilidade óssea para a reabilitação por implantes. Conclusão. A preservação alveolar com a matriz de colágeno cumpriu com seu objetivo e, a reabilitação por implante dentário em alvéolo cicatrizado é uma modalidade eficaz na reabilitação de pacientes desdentados... (AU)

Introduction. Due to local trauma, during tooth extraction, or the lack of masticatory stimuli, the absence of teeth promotes biological responses that trigger a process of bone resorption. Alveolar bone promotion minimizes alveolar bone resorption, promoting high bone bioavailability for rehabilitation with dental implants. Dental implants are a treatment modality to edentulous. Objective. Report a case of implant rehabilitation in a healed socket after alveolar preservation. Case report. Patient A.L.L., male, 23 years old, attended the UNIBRA dental clinic. On physical examination, a wide coronary destruction of element 25 was observed and, on radiographic examination, endodontic treatment was noted. The proposed treatment was a minimally traumatic tooth extraction, alveolar preservation with collagen matrix and implant placement in healed sockets. Discussion. In edentulous patients, the lack of masticatory stimuli promotes an imbalance in bone turnover, triggering a resorption process. Alveolar preservation by collagen matrix aims to minimize resorption and provide greater bone bioavailability for implant rehabilitation. Conclusion. Alveolar preservation with collagen matrix fulfilled its objective, and rehabilitation by dental implant in a healed socket is an effective modality in the rehabilitation of edentulous patients... (AU)

Introducción. Por traumatismo local, durante la extracción dentaria, o por falta de estímulos masticatorios, la ausencia de dientes promueve respuestas biológicas que desencadenan un proceso de reabsorción ósea. La preservación ósea alveolar propone minimizar la reabsorción ósea alveolar, promoviendo una mayor biodisponibilidad ósea para la rehabilitación mediante implantes dentales. Los implantes dentales son una modalidad terapéutica eficaz para la rehabilitación de dientes perdidos. Objetivo. reportar un caso de rehabilitación con implantes en un alvéolo cicatrizado después de preservación alveolar. Reporte de un caso. Paciente A.L.L., masculino, 23 años, acudió a la clínica odontológica de la UNIBRA. El examen físico reveló destrucción coronaria extensa del elemento 25 y el examen radiográfico reveló tratamiento endodóntico. El tratamiento propuesto fue extracción dental mínimamente traumática, preservación alveolar con matriz de colágeno y colocación de implante dental en alvéolo cicatrizado. Discusión. En pacientes edéntulos, la falta de estímulos masticatorios promueve un desequilibrio en el recambio óseo, desencadenando un proceso de reabsorción. La preservación alveolar mediante matriz de colágeno tiene como objetivo minimizar la reabsorción y proporcionar una mayor biodisponibilidad ósea para la rehabilitación con implantes. Conclusión. La preservación alveolar con matriz de colágeno cumplió su objetivo, y la rehabilitación mediante implante dental en un alvéolo cicatrizado es una modalidad eficaz en la rehabilitación de pacientes edéntulos... (AU)

Vertical bone augmentation with guided bone regeneration: a scoping review / Aumento óseo vertical con regeneración ósea guiada: scoping review

Introduction: There are multiple techniques for vertical bone augmentation. Guided bone regeneration is one of them; however, the literature is diverse and includes different study designs, which makes it difficult to synthesize results. Objective: To analyze the general technical characteristics, clinical results, and complications of vertical bone augmentation performed with guided bone regeneration in humans. Material and Methods: This scoping review was based on the PRISMA-ScR guidelines. A search was performed in the Pubmed, Scielo, and Worldcat databases. Papers published from 1990 to April 2020 were included in the study. Research articles not conducted in humans or published in languages other than English and Spanish were excluded. Title and abstract were screened by two reviewers, then full studies were extracted, and data tabulated. Results: 89 studies were included. The highest percentage reported having obtained a vertical bone increase of less than 5 mm and having used non-resorbable membranes. The most frequent type of graft is autogenous and combinations of grafts, the most common being autogenous with xenograft. All studies that reported bone stability of implants in regenerated bone were favorable, as was implant survival, reporting values between 83.8% and 100%. Membrane exposure is the most frequently reported complication, followed by infection or abscesses, and tissue dehiscence. Conclusion: Vertical bone regeneration is a reliable technique, with high predictability and low incidence of complications compared to other vertical bone augmentation techniques.

Introducción: Existen múltiples técnicas para el aumento óseo vertical siendo una opción la regeneración ósea guiada, sin embargo, la literatura es diversa y con distintos diseños que dificultan la síntesis de resultados. Objetivo: Analizar las características generales técnicas, resultados clínicos y complicaciones del aumento óseo vertical realizado con regeneración ósea guiada en humanos. Material y Métodos: Esta revisión de alcance se basó en la guía PRISMA-ScR. Se realizó una búsqueda en las bases de datos Pubmed, Scielo y Worldcat. Fueron incluidos aquellos publicados desde el año 1990 hasta abril de 2020. Se excluyeron los estudios no realizados en humanos o publicados en idiomas distintos al inglés y español. Dos revisores examinaron título y resumen, luego los estudios completos se extrajeron y se ordenaron los datos en tablas. Resultados: 89 estudios fueron incluidos. El mayor porcentaje reportó haber obtenido un aumento óseo vertical menor a 5 mm y haber utilizado membranas no reabsorbibles. El tipo de injerto que más frecuente es el autógeno y las combinaciones de injertos, siendo el más común autógeno con xenoinjerto. Todos los estudios que reportaron estabilidad ósea de implantes en hueso regenerado fueron favorables, al igual que la supervivencia de implantes, reportando valores entre 83,8% y 100%. La exposición de membrana es la complicación que más se repite en los estudios, seguido por infección o abscesos y dehiscencia de tejidos. Conclusión: La regeneración ósea vertical es una técnica confiable, con alta predictibilidad y baja incidencia de complicaciones en comparación a otras técnicas de aumento óseo vertical.

CoCrMo alloy as biomaterial for bone reconstruction in oral and maxillofacial surgery: a scoping review / Aleación de CoCrMo como biomaterial para la reconstrucción ósea en cirugía oral y maxilofacial: una revisión del alcance

Background: Osseointegration allowed for a breakthrough in biomaterials and techniques and it has contributed to increased application of dental implants. However, insufficient bone level is a frequent problem and it creates an anatomically less favourable base for implant placement. The first surgical procedure should comprise the reconstruction of the alveolar bone height. CoCrMo alloys are nowadays considered as highly corrosion resistant and biocompatible materials in dentistry, and therefore has been suggested as a suitable biomaterial for guided bone regeneration and tissue engineering. Aim: To determine the use of CoCrMo alloy for implantable devices in oral and maxillofacial surgery and to discuss the potential of this alloy for bone regeneration and repair through a scoping review. Material and methods: The search was done by using various databases including PubMed, Thomson Reuters and Scopus. We selected English literature related to studies reporting the CoCrMo properties and manufacturing processes and findings related to bone-forming techniques. Data was compared qualitatively. Results: 90 studies were selected according to the inclusion criteria. We reported different manufacturing techniques and their advantages related to mechanical, chemical and biocompatible properties. Conclusion: Improved tissue reactions of CoCrMo implant devices can be acquired by the application of novel techniques and surface modifications. Moreover, several processes have demonstrated to improve the in vitro and in vivo biocompatibility of the CoCrMo alloy to promote the attachment, proliferation and guided differentiation of seeding cells.

Antecedentes: La osteointegración ha permitido un gran avance en biomateriales y técnicas, y ha contribuido un mayor uso de implantes dentales. Sin embargo, la existencia de un nivel óseo insuficiente es un problema frecuente y crea una base anatómicamente menos favorable para la colocación de implantes. El primer procedimiento quirúrgico debe comprender la reconstrucción de la altura del hueso alveolar. Las aleaciones de CoCrMo se consideran hoy en día como materiales altamente resistentes a la corrosión y biocompatibles en odontología y, por lo tanto, se ha sugerido como un biomaterial adecuado para la regeneración ósea guiada y la ingeniería de tejidos. Objetivo: Determinar el uso de la aleación CoCrMo para dispositivos implantables en cirugía oral y maxilofacial y discutir sobre el potencial de esta aleación para la regeneración y reparación ósea a través de una revisión de alcance. Material y Métodos: La búsqueda se realizó utilizando varias bases de datos, incluidas PubMed, Thomson Reuters y Scopus. Se seleccionó literatura inglesa relacionada con estudios que informan sobre las propiedades de CoCrMo y los procesos de fabricación y los hallazgos relacionados con las técnicas de formación de huesos. Los datos se compararon cualitativamente. Resultados: Se seleccionaron 90 estudios según los criterios de inclusión. y se reportaron diferentes técnicas de fabricación y sus ventajas relacionadas con propiedades mecánicas, químicas y biocompatibles. Conclusión: Las reacciones tisulares mejoradas de los dispositivos de implante CoCrMo pueden adquirirse mediante la aplicación de nuevas técnicas y modificaciones de la superficie. Además, varios procesos han demostrado mejorar la biocompatibilidad in vitro e in vivo de la aleación CoCrMo para promover la unión, proliferación y diferenciación guiada de las células de siembra.

Anatomical variations of the maxillary sinus septa of an Iranian population using cone-beam computed tomography: a retrospective study / Variaciones anatómicas de los tabiques del seno maxilar de una población iraní mediante tomografía computarizada de haz cónico: estudio retrospectivo

This study sought to assess the internal anatomy of the maxillary sinuses and their septa using cone-beam computed tomography (CBCT) in an Iranian population. Materials and Methods: Resorption of alveolar bone decreases the height of the maxillary alveolar ridge. This height reduction may be so severe that it warrants ridge augmentation by a sinus lift. Manipulation of the maxillary sinuses, as in sinus lift surgery, requires adequate knowledge about the sinus anatomy.Results: Maxillary sinus septum, as an anatomical variation, may complicate the surgical procedures and increase the risk of complications such as sinus membrane perforation. In this retrospective study, 366 sinuses, 190 from females and 176 from males, aged between 10 and 65 years old presenting to the Oral and Maxillofacial Radiology Department of School of Dentistry at Hamadan University of Medical Sciences were evaluated by two oral radiologists. The extension of the maxillary sinuses, presence of septa, number of septa and their location were determined. Data were analyzed using the chi square test (level of significance p≤0.001). The coefficient of agreement between the two oral radiologists was calculated based on Cohen kappa. Septa were present in 40.5% of the maxillary sinuses, out of which, 31.6% had one, 7.9% had two and 1% had three or more septa; 38% of the septa were horizontal while 62% had an oblique orientation. In total, 184 septa were found in 183 patients; out of which, 91 septa were 2mm to 5mm long while 93 septa were longer than 5mm. Conclusions: Comprehensive knowledge about the three-dimensional internal anatomy of the maxillary sinuses acquired by CBCT priorto surgical procedures can greatly help to prevent postoperative complications.

Este estudio buscó evaluar la anatomía interna de los senos maxilares y sus septos mediante tomografía computarizada de haz cónico (CBCT) en una población Iraní. Materiales y Métodos: . La resorción del hueso alveolar disminuye la altura de la cresta alveolar maxilar. Esta reducción de altura puede ser tan severa que justifique el aumento de la cresta mediante una elevación de seno. La manipulación de los senos maxilares, como en la cirugía de elevación del seno, requiere un conocimiento adecuado sobre la anatomía del seno. Resultado: El tabique del seno maxilar, como una variación anatómica, puede complicar los procedimientos quirúrgicos y aumentar el riesgo de complicaciones como la perforación de la membrana sinusal. En este estudio retrospectivo, dos radiólogos orales evaluaron 366 senos, 190 de mujeres y 176 de hombres, con edades comprendidas entre 10 y 65 años que se presentaron en el Departamento de Radiología Oral y Maxilofacial de la Facultad de Odontología de Hamadan University of Medical Sciences. Se determinó la extensión de los senos maxilares, la presencia de septos, el número de septos y su ubicación. Los datos se analizaron mediante la prueba de chi cuadrado (nivel de significación p?0.001). El coeficiente de concordancia entre los dos radiólogos orales se calculó en base a Cohen kappa. Los septos estaban presentes en el 40.5% de los senos maxilares, de los cuales, el 31.6% tenía uno, el 7.9% tenía dos y el 1% tenía tres o más septos; El 38% de los septos eran horizontales, mientras que el 62% tenía una orientación oblicua. En total, se encontraron 184 septos en 183 pacientes; de los cuales, 91 septos tenían de 2mm a 5mm de largo, mientras que 93 septos tenían más de 5mm. Conclusion: El conocimiento exhaustivo sobre la anatomía interna tridimensional de los senos maxilares adquiridos por CBCT antes de los procedimientos quirúrgicos puede ayudar en gran medida a prevenir complicaciones postoperatorias.

Cambios dimensionales de los tejidos peri-implantarios con injertos de tejido conectivo comparado con matrices xenogénicas / Dimensional changes of peri-implant tissues with connective tissue grafts vs. with xenogenic matrices

RESUMEN Objetivo: Comparar los cambios dimensionales de los tejidos peri-implantarios en la zona estética, después de la segunda etapa quirúrgica de injertos de tejido conectivo autógeno comparados con una matriz de colágeno xenogénica, después de 3 meses de cicatrización. Métodos: En una serie de casos de seis pacientes con defectos del reborde alveolar, se realizó un procedimiento de aumento de volumen de tejidos blandos, asignando al azar dos modalidades de tratamiento: injerto de tejido conectivo subepitelial y matriz de colágeno dérmica acelular. Para evaluar los cambios dimensionales se tomaron impresiones antes del aumento y a los 90 días; estas fueron vaciadas para obtener modelos de yeso que fueron digitalizados; las dos imágenes fueron superpuestas; y tras la definición de tres puntos de interés, se calculó mediante un Software (D500 3D dental scanner - 3Shape, Copenhague, Dinamarca), los cambios dimensionales en milímetros. Se indagó por el dolor experimentado por los pacientes usando una escala visual análoga. Resultados: A los 90 días de realizada la cirugía, se observó un aumento en el grosor de los tejidos blandos peri-implantarios de 0,77 mm (rango 0,0-1,3) para el injerto de tejido conectivo, y 0,89 mm (rango 0,3-1,5) para la matriz dérmica acelular. No se encontraron diferencias estadísticamente significativas entre las dos modalidades de tratamiento, en ninguno de los tres puntos evaluados por paciente (p= 0,83; p= 0,83; p= 0,51). En cuanto al dolor experimentado entre el primer y séptimo días, no se encontraron diferencias estadísticamente significativas en la zona receptora intergrupo (p= 0,07; p= 0,12); intragrupo, injerto (p= 0,11) y matriz (p= 0,32); ni en la zona donante del grupo del injerto (p= 0,11). Conclusiones: El aumento en el grosor de los tejidos peri-implantarios fue similar después de 90 días en los dos grupos del estudio(AU)

ABSTRACT Objective: Compare the dimensional changes of peri-implant tissues from the esthetic zone after the second surgical stage of autogenous connective tissue grafting vs. a xenogenic collagen matrix after three months' healing. Methods: A case-series of six patients with alveolar ridge defects underwent a soft tissue volume augmentation procedure, randomly assigning two treatment modes: subepithelial connective tissue graft and acellular dermal collagen matrix. Impressions were taken before augmentation and at 90 days to evaluate the dimensional changes. These were then emptied to obtain plaster models which were then digitalized. The two images were superimposed, and upon definition of three points of interest, the dimensional changes were estimated in millimeters with the software D500 3D dental scanner (3Shape, Copenhagen, Denmark). Inquiries were made about the pain experienced by patients using a visual analogue scale. Results: Ninety days after surgery, increase in thickness of peri-implant soft tissues was 0.77 mm (range 0.0-1.3) for the connective tissue graft and 0.89 mm (range 0.3-1.5) for the acellular dermal matrix. No statistically significant differences were found between the two treatment modes at any of the three points evaluated per patient (p= 0.83, p= 0.83, p= 0.51). With respect to the pain experienced between the first and the seventh days, no statistically significant differences were found in the recipient zone intergroup (p= 0.07, p= 0.12), the graft intragroup (p= 0.11) and the matrix (p= 0.32), or in the donor zone of the graft group (p= 0.11). Conclusions: Increase in the thickness of peri-implant tissues after 90 days was similar in the two study groups(AU)

Manejo de la cresta maxilar atrófica con la técnica de Ridge Split / Management of the Athrofic Maxilar Crest with the Ridge Split Technique

Resumen 14. Introducción: la atrofia ósea del reborde maxilar siempre es una limitante para instalar implantes dentales. El procedimiento de Ridge Split demuestra ser una técnica exitosa para realizar el manejo de los defectos horizontales, aumentando las dimensiones del reborde atrófico para instalar de forma inmediata implantes dentales. Objetivo: describir el uso clínico de la técnica de Ridge Split como tratamiento del aumento óseo en sentido horizontal del maxilar atrófico. Presentación del caso: se presentó el caso de una paciente femenina de 61 años de edad, edéntula parcial, que busca recuperar sus dientes superiores. Al examen clínico presenta solo dos dientes y al examen radiográfico-tomográfico se observó reabsorción ósea severa y neumatización de los senos maxilares. Se planifica instalar dos implantes para realizar una sobre dentadura, utilizando la técnica de Ridge Split e instalación inmediata de los implantes. Cinco meses posteriores, se realiza un control tomográfico evidenciando aumento horizontal del reborde alveolar y se rehabilita con una sobredentadura, con lo que se logró la conformidad estética y funcional de la paciente. Conclusión: el caso presentado revela que esta técnica incrementa el reborde oseo en sentido horizontal y permite instalar en forma simultánea los implantes. Es un tratamiento predecible, seguro y cómodo, y acorta el tiempo de tratamiento, por lo que es una alternativa viable para el manejo de los defectos óseos alveolares.

Abstract 20. Introduction: the bony atrophy of the maxillary ridge is always a limitation to install dental implants. The Ridge Split procedure proves to be a successful technique to perform the management of horizontal defects, increasing the dimensions of the atrophic ridge to immediately install dental implants. Aim: to describe the clinical use of the Ridge Split technique as a treatment for bone augmentation in the horizontal direction of the atrophic maxilla. Case presentation: the case of a female patient of 61 years of age, partially edentulous, who seeks to recover her upper teeth was presented. The clinical examination shows only two teeth and the radiographic-tomographic examination showed severe bone resorption and pneumatization of the maxillary sinuses. It is planned to install two implants to make an over denture, using the Ridge Split technique and immediate installation of the implants. Five months later, a tomographic control was performed evidencing a horizontal increase of the alveolar ridge and it was rehabilitated with an overdenture, with which the patient's aesthetic and functional compliance was achieved. Conclusion: the presented case reveals that this technique increases the bone ridge in horizontal direction and allows to install the implants simultaneously. It is a predictable, safe and comfortable treatment, and shortens the treatment time, making it a viable alternative for the management of alveolar bone defects.

Influence of wound closure on volume stability with the application of different GBR materials: an in vitro cone-beam computed tomographic study

PURPOSE: To assess the influence of using different combinations of guided bone regeneration (GBR) materials on volume changes after wound closure at peri-implant dehiscence defects. METHODS: In 5 pig mandibles, standardized bone defects were created and implants were centrally placed. The defects were augmented using different combinations of GBR materials: xenogeneic granulate and collagen membrane (group 1, n=10), xenogeneic granulate and alloplastic membrane (group 2, n=10), alloplastic granulates and alloplastic membrane (group 3, n=10). The horizontal thickness was assessed using cone-beam computed tomography before and after suturing. Measurements were performed at the implant shoulder (HT0) and at 1 mm (HT1) and 2 mm (HT2) below. The data were statistically analysed using the Wilcoxon signed-rank test to evaluate within-group differences. Bonferroni correction was applied when calculating statistical significance between the groups. RESULTS: The mean horizontal thickness before suturing was 2.55±0.53 mm (group 1), 1.94±0.56 mm (group 2), and 2.49±0.73 mm (group 3). Post-suturing, the values were 1.47±0.31 mm (group 1), 1.77±0.27 mm (group 2), and 2.00±0.48 mm (group 3). All groups demonstrated a loss of horizontal dimension. Intragroup changes exhibited significant differences in group 1 (P < 0.001) and group 3 (P < 0.01). Intergroup comparisons revealed statistically significant differences of the relative changes between groups 1 and 2 (P=0.033) and groups 1 and 3 (P=0.015). CONCLUSIONS: Volume change after wound closure was minimized by using an alloplastic membrane. The stability of the augmented horizontal thickness was most ensured by using this type of membrane irrespective of the bone substitute material used for membrane support.

Systemic supplement with resveratrol increased bone formation in rats' alveolar socket / Aumento de la formación ósea en el hueso alveolar de rata con suplemento sistémico con resveratrol

Resveratrol in cell culture media increases osteoblastic markers. Also results from previous studies provide evidence for resveratrol positive effects on bone healing and bone production. In this preclinical study we investigated bone healing in rats by resveratrol systemic application. 30 Wistar male rats were divided into two groups (study group and control group). At first, maxillary second molars of rats were extracted. The rats were kept in laboratory for next 28 days. Study group received resveratrol 20 mg/kg by abdominal injection every day. The control group received placebo in the same manner that study group. Rats were sacrificed after 28 days and bone samples were collected from center of maxillary second molar socket. Samples were evaluated histologically for new bone formation, inflammation, necrosis, fibrosis and foreign body reaction. The mean difference of new bone formation in control group (28.30 %) and study group (45 %) were statistically significant (P=0.014). There were no significant differences in inflammation, fibrosis, necrosis and foreign body reaction (P>0.05). Resveratrol has positive effects on bone healing but more evidence needed from more clinical and animal studies.

El resveratrol en los medios de cultivo celular aumenta los marcadores osteoblásticos. Los resultados de estudios anteriores proporcionan evidencia de efectos positivos del resveratrol sobre la curación ósea y la producción ósea. En este estudio preclínico, investigamos la curación ósea en ratas mediante la aplicación sistémica de resveratrol. Se dividieron 30 ratas macho Wistar en dos grupos (estudio y control). Inicialmente se extrajeron los segundos molares maxilares de las ratas y los animales se mantuvieron en el laboratorio durante los siguientes 28 días. El grupo de estudio recibió todos los días resveratrol 20 mg/kg por inyección abdominal . El grupo control recibió placebo de la misma manera que el grupo estudio. Las ratas fueron sacrificadas después de 28 días y se recogieron muestras de hueso del centro del segundo molar maxilar. Las muestras se evaluaron histológicamente para la formación de hueso nuevo, inflamación, necrosis, fibrosis y reacción de cuerpo extraño. La media de formación de hueso nuevo en el grupo control (28,30 %) y en el grupo estudio (45 %) fueron estadísticamente significativas (P=0,014). No hubo diferencias significativas en la inflamación, fibrosis, necrosis y reacción al cuerpo extraño (P>0,05). El resveratrol tiene efectos positivos sobre la curación de los huesos, pero aún es necesario realizar más pruebas de estudios clínicos, como también en animales.

Aparición de exostosis 7 años después de aumento del reborde alveolar con técnica de bolsillo / Exostosis 7 years after alveolar ridge augmentation with pocket technique

Antecedentes: Las técnicas de manejo de tejidos blandos para aumentar rebordes alveolares atrofiados incluyen el uso de injertos de tejido conectivo, con o sin collar de epitelio, y técnicas en rollo. Algunas veces generan complicaciones posoperatorias. Objetivo: Describir el caso de una paciente a la que se le realizó aumento de reborde alveolar y se produjo una exostosis. Caso clínico: A una paciente de 35 años se le realizó un aumento del reborde alveolar con la técnica de bolsillo en el área del diente incisivo central superior derecho. Se tomó un injerto de tejido conectivo sin collar epitelial del paladar que se trasplantó y cubrió con el colgajo. La paciente regresó siete años después y clínicamente presentaba una aparente exostosis en la zona vestibular del diente tratado que la afectaba estéticamente. Se realizó osteoplastia para mejorar el contorno y se tomó una biopsia del hueso cuya histopatología mostró un tejido compatible con hueso alveolar. Conclusiones: La exostosis es una complicación posoperatoria inusual en casos de reborde alveolar que puede ser tratado con éxito. Se requiere más investigación sobre dichos efectos.

Background: Soft-tissue treatment techniques for alveolar ridge augmentation include connective tissue grafts, with or without epithelial collar, and roll techniques. Sometimes, there are postoperative complications. Purpose: To describe a case for a female patient who underwent an alveolar ridge augmentation and developed an exostosis. Case description: A 35-year-old female patient underwent an alveolar ridge augmentation procedure through a pocket technique in the upper right central incisor. A connective tissue graft without epithelial collar from the palate was transplanted and covered with the flap. Seven years later the patient returned with an exostosis in the buccal area of the treated tooth that affected her aesthetically. An osteoplasty was performed and a bone biopsy was taken, whose histopathological analysis showed a bone-compatible tissue. Conclusion: Exostosis is an unusual postoperative complication in cases of alveolar ridge augmentation that can be successfully treated. More research is necessary about such complications.

Alveolar ridge preservation with a collagen material: a randomized controlled trial

PURPOSE: Resorption of the alveolar bone is an unavoidable consequence of tooth extraction when appropriate alveolar ridge preservation (ARP) measures are not taken. The objective of this trial was to test the hypothesis that dimensional changes in the alveolar bone after tooth extraction would be reduced by inserting an equine collagen membrane and a collagen cone to fill and seal the alveolus (as ARP), in comparison to extraction with untreated alveoli. METHODS: In this randomized clinical trial, 31 patients were directly treated with the collagen material after extraction of a tooth from the maxilla (the ARP group). Twenty-nine patients served as the control group. After extraction, no further treatment (i.e., no socket preservation measures) was performed in the control group. Changes in the alveolar process immediately after extraction and after an 8 (±1)-week healing period were evaluated 3-dimensionally. Blinded analyses were performed after superimposing the data from the digitalized impressions and surfaces generated by cone-beam computed tomography. RESULTS: Both the ARP and control groups showed a reduction of bone in the alveolar area after tooth extraction. However, significantly less bone resorption was detected in the clinically relevant buccal region in the ARP group. The median bone reduction was 1.18 mm in the ARP group and 5.06 mm in the control group (P = 0.03). CONCLUSIONS: The proposed hypothesis that inserting a combination material comprising a collagen cone and membrane would lead to a difference in alveolar bone preservation can be accepted for the clinically relevant buccal distance. In this area, implantation of the collagen material led to significantly less alveolar bone resorption. German Clinical Trials Register at www.drks.de, DRKS00004769.

Oral tissue response to soft tissue expanders prior to bone augmentation: in vitro analysis and histological study in dogs

PURPOSE: To determine whether the swelling and mechanical properties of osmotic self-inflating expanders allow or not the induction of intraoral soft tissue expansion in dogs. METHODS: Three different volumes (0.15, 0.25, and 0.42 mL; referred to respectively as the S, M, and L groups) of soft tissue expanders (STEs) consisting of a hydrogel core coated with a silicone-perforated membrane were investigated in vitro to assess their swelling behavior (volume swelling ratio) and mechanical properties (tensile strength, tensile strain). For in vivo investigations, the STEs were subperiosteally inserted for 4 weeks in dogs (n=5). Soft tissue expansion was clinically monitored. Histological analyses included the examination of alveolar bone underneath the expanders and thickness measurements of the surrounding fibrous capsule. RESULTS: The volume swelling ratio of all STEs did not exceed 5.2. In tensile mode, the highest mean strain was registered for the L group (98.03±0.3 g/cm), whereas the lowest mean value was obtained in the S group (81.3±0.1 g/cm), which was a statistically significant difference (P < 0.05). In addition, the S and L groups were significantly different in terms of tensile strength (1.5±0.1 g/cm for the S group and 2.2±0.1 g/cm for the L group, P < 0.05). Clinical monitoring showed successful dilatation of the soft tissues without signs of inflammation up to 28 days. The STEs remained volumetrically stable, with a mean diameter in vivo of 6.98 mm, close to the in vitro post-expansion findings (6.69 mm). Significant histological effects included highly vascularized collagen-rich fibrous encapsulation of the STEs, with a mean thickness of 0.67±0.12 mm. The bone reaction consisted of resorption underneath the STEs, while apposition was observed at their edges. CONCLUSIONS: The swelling and mechanical properties of the STEs enabled clinically successful soft tissue expansion. A tissue reaction consisting of fibrous capsule formation and bone loss were the main histological events.

Effects of strontium ranelate on alveolar ridge morphology augmentation / Efectos del ranelato de estroncio en el aumento del rebforde alveolar

SUMMARY: The objective of this study was to compare the Primary and Secondary stability of immediate implant placement with Alveolar Ridge Augmentation (ARA) and Strontium Ranelate (SR) as aids to enhance the stability using Resonance Frequency Analysis (RFA). Fifty eight subjects ideal for immediate implants were assigned to two groups to compare the primary and secondary stability of the implant using Alveolar Ridge Augmentation and oral strontium ranelate. They were tested for primary stability on placement of the implant and after eight weeks of placement for secondary stability. The stability was measured using resonance frequency analysis. Both the procedures showed an improvement in the stability but the Alveolar Ridge Augmentation procedure showed a significantly better primary stability (P< .03) and the secondary stability (P<.00). The means of the implant stability quotient value (ISQ) for the Alveolar ridge augmentation procedure was 74.2 for primary stability, and 83.34 for secondary stability. With the enhancement of stability with both the procedures Alveolar Ridge Augmentation proved to be a better procedure to achieve successful results of an immediately placed implant.

RESUMEN: El objetivo de este estudio fue comparar la estabilidad primaria y secundaria de la colocación inmediata del implante con el aumento de reborde alveolar (ARA) y el ranelato de estroncio (SR) como ayudas para mejorar la estabilidad mediante el análisis de frecuencia de resonancia (RFA). Cincuenta y ocho sujetos, ideales para implantes inmediatos, fueron asignados a dos grupos para comparar las estabilidades primaria y secundaria del implante usando el aumento del reborde alveolar y el ranelato de estroncio oral. Se efectuaron pruebas de estabilidad primaria en la colocación del implante, y después de ocho semanas para la estabilidad secundaria. La estabilidad se midió utilizando análisis de frecuencia de resonancia. Ambos procedimientos mostraron una mejora en la estabilidad, sin embargo el procedimiento del aumento del reborde alveolar mostró una estabilidad primaria significativamente mejor (P <0,03) que la estabilidad secundaria (P <0,00). Las medias del valor de cociente de estabilidad del implante (ISQ) para el procedimiento de aumento de reborde alveolar fueron 74,2 para la estabilidad primaria y 83,34 para la estabilidad secundaria. Se observó una mejora de la estabilidad en ambos procedimientos, el aumento del reborde alveolar demostró ser un mejor procedimiento para lograr resultados exitosos del posicionamiento de implante inmediato.

Treatment concepts for the posterior maxilla and mandible: short implants versus long implants in augmented bone

The aim of this narrative review is to describe treatment options for the posterior regions of the mandible and the maxilla, comparing short implants vs. longer implants in an augmented bone. The dental literature was screened for treatment options enabling the placement of dental implants in posterior sites with a reduced vertical bone height in the maxilla and the mandible. Short dental implants have been increasingly used recently, providing a number of advantages including reduced patient morbidity, shorter treatment time, and lower costs. In the posterior maxilla, sinus elevation procedures were for long considered to be the gold standard using various bone substitute materials and rendering high implant survival rates. More recently, implants were even placed without any further use of bone substitute materials, but the long-term outcomes have yet to be documented. Vertical bone augmentation procedures in the mandible require a relatively high level of surgical skill and allow the placement of standard-length dental implants by the use of autogenous bone blocks. Both treatment options, short dental implants, and standard-length implants in combination with vertical bone augmentation procedures, appear to result in predictable outcomes in terms of implant survival rates. According to recent clinical studies comparing the therapeutic options of short implants vs. long implants in augmented bone, the use of short dental implants leads to a number of advantages for the patients and the clinician.

A comparison of different compressive forces on graft materials during alveolar ridge preservation

PURPOSE: Following tooth extraction, alveolar ridge preservation (ARP) can maintain the dimensions of ridge height and width. Although previous studies have demonstrated the effects of ARP, few if any studies have investigated the compressive force applied during grafting. The aim of this study was to determine the effects of different compressive forces on the graft materials during ARP. METHODS: After tooth extraction, sockets were filled with deproteinized bovine bone mineral with 10% porcine collagen and covered by a resorbable collagen membrane in a double-layered fashion. The graft materials were compressed using a force of 5 N in the test group (n=12) and a force of 30 N in the control group (n=12). A hidden X suture was performed to secure the graft without primary closure. Cone-beam computed tomography (CBCT) was performed immediately after grafting and 4 months later, just before implant surgery. Tissue samples were retrieved using a trephine bur from the grafted sites during implant surgery for histologic and histomorphometric evaluations. Periotest values (PTVs) were measured to assess the initial stability of the dental implants. RESULTS: Four patients dropped out from the control group and 20 patients finished the study. Both groups healed without any complications. The CBCT measurements showed that the ridge volume was comparably preserved vertically and horizontally in both groups (P>0.05). Histomorphometric analysis demonstrated that the ratio of new bone formation was significantly greater in the test group (P0.05). CONCLUSIONS: The application of a greater compressive force on biomaterials during ARP significantly enhanced new bone formation while preserving the horizontal and vertical dimensions of the alveolar ridge. Further studies are required to identity the optimal compressive force for ARP.

Regenerative capacity of augmented bone in rat calvarial guided bone augmentation model

PURPOSE: Guided bone regeneration (GBR) is the most widely used technique to regenerate and augment bones. Even though augmented bones (ABs) have been examined histologically in many studies, few studies have been conducted to examine the biological potential of these bones and the healing dynamics following their use. Moreover, whether the bone obtained from the GBR procedure possesses the same functions as the existing autogenous bone is uncertain. In particular, little attention has been paid to the regenerative ability of GBR bone. Therefore, the present study histologically evaluated the regenerative capacity of AB in the occlusive space of a rat guided bone augmentation (GBA) model. METHODS: The calvaria of 30 rats were exposed, and plastic caps were placed on the right of the calvaria in 10 of the 30 rats. After a 12-week healing phase, critical-sized calvarial bone defects (diameter: 5.0 mm) were trephined into the dorsal parietal bone on the left of the calvaria. Bone particles were harvested from the AB or the cortical bone (CB) using a bone scraper and transplanted into the critical defects. RESULTS: The newly generated bone at the defects' edge was evaluated using micro-computed tomography (micro-CT) and histological sections. In the micro-CT analysis, the radiopacity in both the augmented and the CB groups remained high throughout the observational period. In the histological analysis, the closure rate of the CB was significantly higher than in the AB group. The numbers of cells positive for runt-related transcription factor 2 (Runx2) and tartrate-resistant acid phosphatase (TRAP) in the AB group were larger than in the CB group. CONCLUSIONS: The regenerative capacity of AB in the occlusive space of the rat GBA model was confirmed. Within the limitations of this study, the regenerative ability of the AB particulate transplant was inferior to that of the CB particulate transplant.

Histomorphometric evaluation of ridge preservation after molar tooth extraction / 北京大学学报(医学版)

Objective:To evaluate bone formation in human extraction sockets with absorbed surrounding walls augmented with Bio-Oss(R) and Bio-Gide(R) after a 6-month healing period by histologic and histomorphometric analyses.Methods:Six fresh molar tooth extraction sockets in 6 patients who required periodontally compromised moral tooth extraction were included in this study.The six fresh extraction sockets were grafted with Bio-Oss(R) particle covered with Bio-Gide(R).The 2.8 mm × 6.0 mm cylindric bone specimens were taken from the graft sites with aid of stent 6 months after the surgery.Histologic and histomorphometric analyses were performed.Results:The histological results showed Bio-0ss(R) particles were easily distinguished from the newly formed bone,small amounts of new bone were formed among the Bio-Oss(R) particles,large amounts of connective tissue were found.Intimate contact between the newly formed bone and the small part of Bio-Oss(R) particles was present.All the biopsy cylinders measurement demonstrated a high inter-individual variability in the percentage of the bone,connective tissues and BioOss(R) particles.The new bone occupied 11.54％ (0-28.40％) of the total area;the connective tissues were 53.42％ (34.08％-74.59％) and the Bio-Oss(R) particles were 35.04％ (13.92％-50.87％).The percentage of the particles,which were in contact with bone tissues,amounted to 20.13％ (0-48.50％).Conclusion:Sites grafted with Bio-Oss(R) particles covered with Bio-Gide(R) were comprised of connective tissues and small amounts of newly formed bone surrounding the graft particles.