Partial extraction therapies (PET): a review of the literature / Terapias de extração parcial (TEP): uma revisão da literatura

ABSTRACT One of the most common dental procedures is tooth extraction; however, the bone defect resulting from the process is only partially restored, leading to considerable bone loss. To rehabilitate a fully or partially edentulous patient, we must handle these sites with delicate surgical procedures. There is a large literature presenting attempts to overcome the negative effects of a dental extraction, with the aim of reducing tissue volume loss or restoring the alveolar architecture. In this context, Partial Extraction Therapy (PET) represents a subgroup of interventions to prevent bone loss after extraction using the tooth itself to prevent alveolar bone loss. This literature review aims to make a survey of the published articles on PET, with an emphasis on socket shield technique, and to explain the other techniques such as root burial, pontic-shield and proximal socket-shield, their indications and counter indications in order to deepen the knowledge of these techniques. To identify the included or considered studies, we adopted a detailed search strategy for MEDLINE and Cochrane Library focused in the last 31 years, whose language was English, Spanish or Portuguese. This text presents an analysis of current data regarding the alternatives for alveolar preservation and the installation of immediate implants in these areas, presenting the possibility of a different surgical technique. However, due to the immaturity and lack of conclusive scientific evidence regarding the predictability of the procedures, it is considered that the use of the socket shield technique must be done in an extremely cautious way.

RESUMO Um dos procedimentos odontológicos mais comuns é a extração dentária, contudo, , o defeito ósseo decorrente do processo é apenas parcialmente restaurado, levando a uma perda ossea volumétrica consideravel. Para reabilitar um paciente totalmente ou parcialmente desdentado, devemos manusear estes sitios com intervenções cirúrgicas delicadas. Há uma vasta literatura apresentando tentativas de transpor os efeitos negativos de uma extração dentária, com o objetivo de diminuir a perda volumétrica tecidual ou restaurar a arquitetura alveolar. Neste contexto, a Terapia de Extração Parcial (TEP) representa um subgrupo de intervenções para prevenir a perda óssea após exodontia, usando o próprio dente para prevenir a perda óssea alveolar. Essa revisão de literatura tem por objetivo fazer um levantamento dos artigos publicados sobre as TEP, com ênfase na técnica de socket shield, e explanar a cerca das demais técnicas como sepultamento radicular, pontic-shield e proximal socket-shield, suas indicações e contra-indicações, a fim de aprofundar o conhecimento dessas técnicas. Para a identificação dos estudos inclui?dos ou considerados, adotamos a estrate?gia de busca detalhada para os bancos MEDLINE e Biblioteca Cochrane nos u?ltimos 31 anos, cujo idioma fosse o ingle?s, espanhol ou o portugue?s. Este texto, apresenta uma análise de dados atuais a respeito das alternativas para a preservação alveolar e instalação de implantes imediatos nestas áreas, apresentando a possibilidade de uma técnica cirúrgica diferenciada. No entanto, devido a imaturidade e falta de comprovação cientifica contundente a respeito da previsibilidade dos procedimentos, considera-se que o emprego da técnica de socket shield deve ser feito de forma cautelosa.

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.

Histopathological evaluation of the effect of Salvadoria persica and Nigella sativa on the healing of tooth extraction socket in animal

To assess the effects of Salvadoria persica and Nigella sativa combination in tooth socket healing after extraction that can be a novel remedy for tooth extraction socket. Methods: Forty rabbits were included in this study, divided into two groups (control and experimental) with 20 rabbits. Upper right central incisors were extracted for all animals, the tooth sockets of the experimental group were dressed using an admix of Salvadoria persica and Nigella sativa immediately after irrigation with normal saline. In contrast, the extraction sockets of the control group were left without dressing. Biopsies were taken after euthanizing the animals at 1, 3, 7, and 14 days after treatment, histological examination was done for the samples at the given periods respectively. Results: On day 1 post-treatment, histological examination of the experimental group sections showed less acute inflammatory reaction than the control group. This continued to be reduced until the seventh day. The amount of granulation tissue formation was more in the experimental group along the different periods of the study, while new bone formation was observed after 1 week as woven bone, increased after 2 weeks and appeared as woven and lamellar bone in both experimental and control groups. Conclusions: A mixture of Salvadoria persica and Nigella sativa has an anti-inflammatory effect and accelerate bone healing by stimulating bone formation in the tooth extraction socket

Research progress in the design of surgical flaps for impacted mandibular third molars / 中国基层医药

The incidence of impacted mandibular third molars is high. Many complications occur after extraction of impacted third molars, such as bleeding, pain, swelling, and dry grooves, which affect quality of life. To reduce postoperative complications, various skin flap designs have emerged with time. This paper summarizes the current research progress in designing impacted mandibular third molar flaps, providing a reference for clinical work.

The effect of scaffold hydroxyapatite derived from portunus pelagicus shell on the expression of fibroblast growth factor-2 (fgf-2) and bone morphogenetic proteins-2 (bmp -2) in the extraction sockets of cavia cobaya / El efecto del scaffold de hidroxiapatita derivada de portunus pelagicus sobre la expresión del factor de crecimiento de fibroblastos-2 (FGF-2) y las proteínas morfogenéticas óseas-2 (BMP-2) en los alvéolos dentarios de cavia cobaya

Objetive: To determine the expression of Fibroblast Growth Factor (FGF)-2 and Bone Morphogenetic Protein (BMP)-2 after application of scaffold hydroxyapatite from Rajungan crab shell (Portunus pelagicus) in the tooth extraction socket of Cavia cobaya. Material and Methods: This study used a post-test only control group design with 28 Cavia cobaya separated into two groups, control and treatment group. The left mandibular incisor was extracted, and socket preservation was conducted. A hydroxyapatite graft derived from crab shells was mixed with gelatin and eventually turned into a scaffold, which was afterward put into the extraction socket. After 7 days and 14 days, each group was terminated and examined using immunohistochemical staining to observe the expression of FGF-2 and BMP-2. One-Way Anova and Tukey HSD were used to examine the research data. Results: FGF-2 and BMP-2 expressions were observed higher in the group that received hydroxyapatite scaffold at the post-extraction socket than those in the group that did not receive hydroxyapatite scaffold. Conclusion: The application of a hydroxyapatite scaffold from Rajungan crab shell (Portunus pelagicus) to the tooth extraction socket can increase FGF-2 and BMP-2 expression.

Objetivo: Determinar la expresión del factor de crecimiento de fibroblastos (FGF)-2 y la proteína morfogenética ósea (BMP)-2 después de la aplicación de hidroxiapatita de andamio de caparazón de cangrejo Rajungan (Portunus pelagicus) en el alvéolo de extracción dental de Cavia cobaya. Material y Métodos: Este estudio utilizó un diseño de grupo de control solo posterior a la prueba con 28 Cavia cobaya separados en dos grupos, grupo de control y grupo de tratamiento. Se extrajo el incisivo mandibular izquierdo y se realizó la preservación del alvéolo. Un injerto de hidroxiapatita derivado de caparazones de cangrejo se mezcló con gelatina y se convirtió en un andamio, que luego se colocó en el alvéolo de extracción. Después de 7 días y 14 días, se terminó cada grupo y se examinó mediante tinción inmunohistoquímica para observar la expresión de FGF-2 y BMP-2. Se utilizaron One-Way Anova y Tukey HSD para examinar los datos de la investigación. Resultados: Las expresiones de FGF-2 y BMP-2 se observaron más altas en el grupo que recibió la estructura de hidroxiapatita en el alvéolo posterior a la extracción que en el grupo que no recibió la estructura de hidroxiapatita. Conclusión: La aplicación de un andamio de hidroxiapatita de caparazón de cangrejo Rajungan (Portunus pelagicus) al alvéolo de extracción dental puede aumentar la expresión de FGF-2 y BMP-2.

Cone-beam computed tomographic evaluation of dimensional hard tissue changes following alveolar ridge preservation with leucocyte and platelet-rich fibrin techniques: a pilot study / Avaliação tomográfica computadorizada de feixe cônico das alterações dimensionais de tecido duro após preservação de crista alveolar com técnicas de fibrina rica em leucócitos e plaquetas: um estudo piloto

Objective: This study evaluated the effect of leucocyte and platelet-rich fibrin (L-PRF) techniques used in alveolar ridge preservation on dimensional hard tissue changes of the alveolar ridge assessed using cone-beam computed tomography (CBCT) scans. Material and Methods: Elective alveolar ridge preservation surgeries were performed on seven systemically healthy patients who underwent single posterior tooth extraction. Patients were randomly treated with PRF mixed with a commercial bone xenograft (n = 3) or PRF plug (n = 4). CBCT scans were taken immediately after tooth extraction and then four months later, just before implant surgery. Dimensional alterations in socket height (SH), socket area (SA) and socket volume (SV) were evaluated on CBCT scans by percentage differences before and after treatments. Results: Sockets treated with PRF plus bone xenograft had a tendency to maintain alveolar bone dimensions over time (SH= 11.22% to 82.74%, SA= 1.84% to 48.91% and SV= 9.11% to 203.62%), while sockets treated only with PRF plug technique presented only a modest increase in height (SH= 1.47% to 11.11%) but greater alveolar ridge resorption confirmed by a decrease in socket area and volume dimensions (SA= 0.21% to -24.09% SV= 8.53% to -54.12%). Conclusion: Within the limitations of this study, the maintenance of alveolar socket dimensions was observed when PRF was associated with a xenograft. However, the loss of alveolar ridge dimensions was not entirely prevented by PRF treatment alone.(AU)

Objetivo: Este estudo avaliou o efeito das técnicas de fibrina rica em leucócitos e plaquetas (L-PRF) usadas na preservação da crista alveolar em alterações dimensionais de tecido duro da crista alveolar avaliadas por tomografia computadorizada de feixe cônico (CBCT). Material e Métodos: Foram realizadas cirurgias eletivas de preservação da crista alveolar em sete pacientes sistemicamente saudáveis que foram submetidos a uma única extração dentária posterior. Os doentes foram tratados aleatoriamente com PRF misturado com um xenoenxerto ósseo comercial (n = 3) ou com PRF plug (n = 4). CBCT foi realizada imediatamente após a extração dentária e quatro meses depois, imediatamente antes da cirurgia de implante. Alterações dimensionais na altura do alvéolo (SH), área do alvéolo (SA) e volume do alvéolo (SV) foram avaliadas em exames CBCT por diferenças percentuais antes e depois dos tratamentos. Resultados: Os alvéolos tratados com PRF mais xenoenxerto ósseo apresentaram tendência a manter as dimensões ósseas alveolares ao longo do tempo (SH= 11.22% a 82.74%, SA= 1.84% a 48.91% e SV= 9.11% a 203.62%), enquanto alvéolos tratados apenas com a técnica de PRF plug apresentaram apenas um aumento modesto na altura (SH= 1.47% a 11.11%), mas uma maior reabsorção alveolar confirmada pela redução das dimensões de área e volume do alvéolo (SA= 0.21% a -24.09% SV= 8.53% a -54.12%). Conclusão: Dentro das limitações deste estudo, a manutenção das dimensões alveolares foi observada quando o PRF foi associado ao xenoenxerto. No entanto, a perda das dimensões alveolares não foi totalmente evitada pelo tratamento apenas com PRF. (AU)

A single session of antimicrobial photodynamic therapy does not influence the alveolar repair process in rats

Abstract: The aim of this study was to use microscopic and molecular techniques to evaluate the effects of a single session of antimicrobial photodynamic therapy (aPDT) on the alveolar repair process after tooth extraction in rats. The study sample included 84 rats divided into four groups, as follows: a) Control - untreated socket; b) Laser - socket treated using photobiomodulation; c) TBO - socket treated with topic application of the photosensitizer agent, toluidine blue O (TBO); and d) aPDT - socket treated with TBO and laser irradiation. An additional rat was used for thermal mapping during socket irradiation. The animals were euthanatized at 6, 15, and 28 days after unilateral extraction of the upper incisor. Quantitative and qualitative analyses of the connective and bone tissues, blood clot, blood vessel, and inflammatory infiltrate were performed, and real-time polymerase chain reaction was used to study the expression of genes (collagen type I, osteocalcin, alkaline phosphatase [ALP], runt-related transcription factor 2 [RUNX2], and vascular endothelial growth factor [VEGF]) involved in the bone healing process. No statistically significant differences in microscopic and molecular outcomes were observed between the groups (p > 0.05). A positive correlation was seen to exist between blood clot and VEGF (p = 0.000), and a negative correlation was observed between bone tissue and ALP (p = 0.028) and blood vessel and VEGF (p = 0.018). A single session of aPDT in the dental extraction site did not influence the alveolar repair process in rats.

Hexavalent chromium exposure alters bone remodeling in the developing tooth alveolus and delays tooth eruption / La exposición a cromo hexavalente altera la remodelación ósea del alvéolo dental en desarrollo y retarda la erupción dentaria

ABSTRACT Although it has been demonstrated that exposure of lactating rats to CrVI delays tooth eruption, the effects of CrVI exposure on bone remodeling in the developing alveolus during tooth eruption remain unknown. Our purpose was to analyze the effect of CrVI in the alveolus of the first lower molar of rats. Thirty-two suckling Wistar rats were divided into two groups. The experimental group received 12.5 mg/kg body weight/day of potassium dichromate dissolved in saline solution by oral gavage as of day 4 of the experiment; the control group received an equal dose of saline solution. Each group was divided into two sub-sets and euthanized at the ages of 9 and 15 days, respectively. Histochemical and histomorphometric studies of the bone surfaces of the developing tooth alveolus were performed. The percentage of bone formation surfaces was lower in experimental animals than in age-matched controls. The percentage of bone resorption surfaces was significantly lower in 9-day-old experimental rats than in controls and significantly higher in 15-day-old experimental rats than in controls. Exposure to CrVI during lactation alters the sequence of bone resorption and formation in the walls of the developing alveolus, both of which are necessary for tooth eruption, thus causing a delay.

RESUMEN Si bien ya ha sido demostrado que la exposición a CrVI de ratas lactantes retrasa la erupción dentaria, aún se desconocen los efectos de la exposición a CrVI que se producen sobre la modelación y remodelación de las paredes del alvéolo en formación que ocurren en los diferentes estadios de la erupción dentaria. Por tal motivo, el propósito de este trabajo fue estudiar el efecto del CrVI sobre la formación y la reabsorción óseas del alvéolo del primer molar inferior en desarrollo en ratas, a los 9 y a los 15 días de edad, que corresponden a los estadios intraóseo y de penetración mucosa de la erupción dentaria, respectivamente. El grupo experimental recibió una dosis diaria de 12,5 mg/kg de peso corporal de dicromato de potasio disuelto en solución salina por sonda bucal a partir del 4° día; mientras que el grupo control, un volumen equivalente de solución salina. Cada grupo fue dividido en 2 subgrupos de acuerdo al tiempo experimental en el que se llevó a cabo la eutanasia: 9 y 15 días de edad. Se llevaron a cabo estudios histoquímicos e histomorfométricos de las superficies óseas de los alveólos dentarios en formación. Los datos fueron analizados estadísticamente utilizando la prueba t de Student; estableciéndose un valor de p<0,05 como estadísticamente significativo. El porcentaje de superficies en formación fue menor en los animales experimentales de 9 y de 15 días de edad que en los respectivos controles. El porcentaje de superficies en reabsorción en los animales experimentales de 9 días de edad fue significativamente menor y en los animales de 15 días de edad fue significativamente mayor con respecto a sus controles. La exposición al cromo hexavalente durante la lactancia altera la secuencia de la reabsorción y la formación ósea de las paredes del alvéolo en desarrollo necesarias para que la pieza dentaria erupcione, causando su retraso. Los hallazgos obtenidos muestran la importancia del control de sustancias tóxicas en el agua potable, ya que sus efectos pueden alterar la remodelación ósea y por ende, el crecimiento y el desarrollo de los individuos que fueron expuestos durante la infancia temprana.

Meta-analysis of the effect of platelet-rich fibrin in alveolar ridge preservation / 口腔疾病防治

Objective @#To evaluate the effect of platelet-rich fibrin (PRF) on alveolar ridge preservation after tooth extraction.@*Methods@#Randomized controlled trials (RCTs) published before August 25, 2020 about the use of PRF after tooth extraction were searched through the PubMed, Embase, Cochrane Library, HowNet, Wanfang, CBM databases and clinical trial registration centers in China and the United States. Outcome indicators included in the studies included dry socket occurrence, alveolar bone resorption in the horizontal and vertical directions, and the percentage of new bone. Meta-analysis was conducted with Review Manager Version 5.3 software.@*Results@# A total of 706 studies were retrieved. After screening, 8 studies were analyzed quantitatively. Meta-analysis results showed that PRF could reduce the absorption of alveolar bone after tooth extraction, which reduced the horizontal bone mass (WMD=-0.71, 95% CI=-1.11 to -0.32, P < 0.05) and buccal (WMD=-1.38, 95% CI =-1.87 to -0.88, P < 0.05) and lingual sides (WMD=-0.49, 95% CI=-0.92 to -0.06, P < 0.05) and increased the percentage of new bone (SMD=1.24, 95% CI =0.25 to 2.23, P < 0.05). However, there was no significant difference in preventing the occurrence of dry socket (RD < 0.01, 95% CI=-0.05 to 0.04, P=0.95) and reducing bone absorption in the vertical direction of mesial (WMD=-0.11, 95% CI=-1.17 to 0.95, P=0.84) and distal (WMD=-0.66, 95% CI=-1.93 to 0.60, P=0.30) alveolar ridge after tooth extraction. @*Conclusion @# Using PRF alone after tooth extraction can effectively preserve bone mass in the horizontal direction of the alveolar ridge and the vertical direction of the buccal and lingual sides.

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)

Consideraciones para el manejo de un implante inmediato en alvéolos infectados: una actualización / Considerations for the management of an immediate implant in infected sockets: an update

Introducción: La instalación inmediata del implante posterior a la extracción dental se está convirtiendo en un procedimiento de rutina debido a la reducción del tiempo de tratamiento y a la preservación de las estructuras anatómicas remanentes. Sin embargo, en muchos casos esta técnica involucra dientes afectados con procesos infecciosos. Hasta ahora, no se ha descrito a ciencia cierta el grado de éxito o fracaso del implante inmediato en alvéolos infectados, ni se ha establecido un protocolo para el manejo de este tipo de casos. Objetivo: Realizar una revisión bibliográfica actualizada, para determinar qué consideraciones se deben tener para instalar un implante inmediato en alvéolos con procesos infecciosos. Conclusión: Es posible obtener las ventajas de la instalación inmediata del implante en alvéolos infectados mediante la aplicación de un adecuado manejo clínico, donde se considere un adecuado tratamiento antibiótico, acompañado de un correcto curetaje alveolar, respetar la cadena de asepsia y antisepsia, posición subcrestal del implante y obtener siempre una buena estabilidad primaria del implante (AU)

Introduction: The immediate placement of the implant after dental extraction is a procedure that every time is becoming a routine procedure due to the reduction of the treatment time and the preservation of the remaining anatomical structures. However, in many cases, this technique involves affected teeth with infectious processes. Until now, the degree of success or failure of the immediate implant in infected alveoli has not been described for sure; nor has a protocol been established for the management of these types of cases. Objective: Carry out an updated bibliographic review, to determine what considerations must be taken to install an immediate implant in alveoli with infectious processes. Conclusion: Is possible obtain the advantages of the immediate installation of the implant in infected alveoli through the application of adequate clinical management, where appropriate antibiotic treatment is considered, accompanied by proper alveolar curettage, respect the aseptic and antiseptic chain, implant subcrestal position and always obtain a good primary stability of the implant (AU)

Técnica de "socket-shield" para la preservación de reborde alveolar. Reporte de caso clínico / Socket-shield technique for the preservation of alveolar ridge. Clinical case report

RESUMEN: Algunas técnicas como la regeneración ósea guiada, uso de rellenos óseos y membranas se han planteado para limitar la reabsorción ósea post exodoncia. La técnica de "socket-shield" preserva un fragmento de raíz vestibular como medio para preservar la cortical ósea bucal. El presente reporte describe un caso clínico de fractura coronaria en un incisivo central superior que fue segmentado parcialmente y la porción vestibular de la raíz fue preservada para mantener la arquitectura de la cortical vestibular, al mismo tiempo se colocó un implante dental. Posterior a la rehabilitación fija, y con un seguimiento de un año se evidenció la preservación de los tejidos blandos periimplantarios a nivel de la mucosa y tejido óseo. No se observó alteraciones en la oseointegración y la pérdida ósea marginal periimplantaria fue nula. Se concluye que la técnica de "socket-shield" parece conservar clínicamente la arquitectura de la mucosa y el tejido óseo sin ocasionar patologías periimplantarias.

ABSTRACT: Some techniques such as guided bone regeneration with the use of bone fillings and membranes have been proposed to limit bone resorption. The socket-shield technique preserves a fragment of the vestibular root as a means of preserving the buccal bone cortex. This report describes a clinical case of coronary fracture in an upper central incisor that was partially segmented and the vestibular portion of the root was preserved to maintain the architecture of the vestibular cortex; at the same time, a dental implant with immediate provisionalization was placed. After the fixed rehabilitation and with a follow-up of one year, the preservation of the soft peri-implant tissues at the level of the mucosa and bone tissue was evidenced. No alterations in osseointegration were observed and marginal peri-implant bone loss was null. It is concluded that the socket-shield technique seems to clinically conserve the architecture of the mucosa and bone tissue without causing peri-implant diseases.

The effects of luteolin nanoparticles on the healing of extracted tooth socket in rabbits

Objective: To evaluate the effects of luteolin nanoparticles on the process tooth socket healing in rabbits. Design: This study comprised five rabbits randomly assigned to control animal and experimental animals. Immediately after the extraction of an upper maxillary incisor, the alveolar sockets of experimental animals were treated with topical luteolin while alveolar sockets of the control group remained without treatment. The animals were sacrificed by decapitation with deep anesthesia seven days post tooth extraction. The tooth sockets were sectioned and stained with hematoxylin and eosin stains. Results: Histological evaluation revealed that luteolin treatment induced earlier healing of extracted tooth sockets. Conclusion: These findings suggest that luteolin accelerates the healing process in tooth sockets of rabbits.

Preservation of dental sockets filled with composite bovine bone. A single-blind randomized clinical trial

Abstract The purpose of this study was to evaluate the preservation of alveolar dimensions in human fresh extraction sockets filled with a composite bovine bone graft by means of design of single-blind randomized clinical trial. Forty participants had monoradicular teeth extracted (one teeth in each participant), and after were randomly divided into 2 groups: individuals whose fresh sockets were filled with the composite heterologous bone graft (Biomaterial Group), or with blood clot (Control Group). After extraction, the fresh sockets were measured at their greatest mesiodistal (MD) and bucco-lingual/palatal (BL/P) distance. Primary closure of the soft tissue was performed with a fibro-mucosal plug. After 120 post-operative days, the re-entry procedure was performed and the largest MD and BL/P measurements were again obtained to calculate the remodeling of the alveolar bone measured in percentage. In the biomaterial group, a percentage reduction of 1.62% and 3.29% in the MD and BL/P dimensions was observed 120 days after the extractions, whereas a reduction of 4.97% and 7.18% in the MD and BL/P dimensions occurred in the control group. There was a statistically significant difference (p<0.05) between the two groups for the bucco-palatal and mesiodistal measurements in the maxilla. In view of the results obtained, it can be concluded that composite bovine bone graft limited but did not impede alveolar bone remodeling.

Resumo O objetivo deste estudo foi avaliar em humanos a manutenção do volume em alvéolos frescos preenchidos por osso integral de origem bovina por meio de um estudo clínico randomizado com monocegamento. Quarenta dentes uni radiculares foram extraídos em 40 pacientes (um dente em cada participante), e apos estes pacientes foram divididos aleatoriamente em 2 grupos: indivíduos que tiveram o alvéolo fresco preenchido por osso integral de origem bovina (Grupo Biomaterial) ou por coagulo sanguíneo (Grupo Controle). Apos a exodontia os alvéolos foram medidos em suas maiores distancias mesio-distal (MD) e vestíbulo lingual/palatina (VL/P) por meio de compasso de ponta seca. O fechamento primário dos alvéolos foi realizado com um tampão fibromucoso. Apos 120 dias pós-operatórios durante o procedimento de reabertura foram obtidas novamente as maiores medidas MD e VL/P para calcular em porcentagem o nível de remodelação do osso alveolar. No grupo biomaterial observou-se uma redução em porcentagem de 1,62% e 3,29% nas medidas MD e VL/P 120 dias apos as extrações, enquanto no grupo controle houve uma redução de 4,97% e 7,18% nas medidas MD e VL/P no mesmo período. Houve diferença estatisticamente significante (p<0,05) entre os dois grupos para as medidas vestíbulo/palatina e mesiodistal na maxila. Diante dos resultados obtidos conclui-se que o osso integral de origem bovina limitou, mas não impediu a remodelação óssea alveolar.

Hyaluronic acid accelerates bone repair in human dental sockets: a randomized triple-blind clinical trial

Abstract This study evaluated the effects of hyaluronic acid (HA) on bone repair of human dental sockets. Thirty-two lower first premolars were extracted from 16 patients (2 per patient) for orthodontic reasons. Following the extractions, one socket was randomly filled with 1% HA gel, while the other was allowed to naturally fill with blood clot. After 30 and 90 days of surgery, patients underwent cone beam computed tomography. Five central orthoradial slices were captured from each socket. The gray intensity was measured in each image and results were reported as mean percentage of bone formation. The buccolingual alveolar ridge width was measured and dimensional changes were compared between the postoperative intervals. The pattern of alveolar trabecular bone was evaluated through the fractal dimension. Treated sockets showed a higher percentage of bone formation and fractal dimension values (58.17% and 1.098, respectively) compared with controls (48.97% and 1.074, respectively) in the 30-day postoperative period (p < 0.05). After 90 days, there was no significant difference between groups. Additionally, no significant difference was found between groups regarding the alveolar dimensions (p > 0.05). Use of 1% HA gel after tooth extraction accelerates bone repair in human dental sockets.

Preservação de alvéolo com uso de materiais xenógenos em área estética da maxila: relato de caso / Ridge preservation using xenografts in an aesthetic area of the maxilla: Case Report

INTRODUÇÃO: Para manter as dimensões ósseas e gengivais do alvéolo até a instalação de implantes tardios o cirurgião dentista pode lançar mão de diversas técnicas de regeneração óssea guiada, dentre estas existentes a associação de um substituto ósseo com um selador do alvéolo vem apresentando resultados clínicos satisfatórios. OBJETIVO: O objetivo do presente trabalho é relatar um caso clínico onde a preservação alveolar em área estética maxilar foi realizada com materiais xenógenos. RELATO DE CASO: Paciente gênero feminino com 50 anos, melanoderma, não fumante e sem alterações sistêmicas apresentou-se a pós-graduação em periodontia da Faculdade de Odontologia de Ribeirão Preto devido a incômodo estético nos elementos 11 e 21. No exame clínico verificou comprometimento periodontal extenso nos dentes 11 e 21 sendo indicada a exodontia com reabilitação oral via implantes dentários. O tratamento proposto foram as exodontias seguidas de preservação alveolar com materiais xenógenos para posterior instalação de implantes na área enxertada. Porém a pedido da paciente e por conta das condições periodontais e estéticas as exodontia foram realizadas em momentos diferentes demonstrando um planejamento diferenciado e individualizado. CONCLUSÃO: Podemos concluir que a associação entre o substituto ósseo com a membrana substituta de tecido mucoso conseguiu obter resultados satisfatórios na preservação e manutenção das dimensões ósseas e teciduais no caso apresentado (AU)

INTRODUCTION: To maintain the bone and gingival dimensions of the ridge until the installation of implants the dental surgeon can use several techniques of guided bone regeneration, among these the association of a bone substitute with a ridge's sealant has shown satisfactory clinical results. OBJECTIVE: The objective of this study is to report a clinical case where ridge preservation in maxillary aesthetic area was performed with xenogenic materials. CASE REPORT: A 50-year-old female patient, melanoderma, non-smoker and no systemic conditions presented at post-graduation in periodontics from the Faculty of Dentistry of Ribeirão Preto due to aesthetic discomfort in elements 11 and 21. At the clinical examination it was verified that there was extensive periodontal impairment on teeth 11 and 21, that why it was indicated an oral rehabilitation with dental implants. The proposed treatment was the exodontia followed by ridge preservation with xenogenic materials for posterior implant installation in the grafted area. However, at the request of the patient and due to the periodontal and aesthetic conditions, the exodontia were performed at different times, demonstrating a different and individualized treatment planning. CONCLUSION: We can conclude that the association between the bone substitute and the mucosal tissue replacement membrane was able to obtain satisfactory results in the preservation and maintenance of the bone and tissue dimensions in the presented case.tissue (AU)

Evaluation of the effect of platelet-rich plasma on alveolar wound healing in rats / Evaluación del efecto del plasma rico en plaquetas en la cicatrización de heridas alveolares en ratas

Opinions about the clinical utility of platelet-rich plasma (PRP) vary, as a large number of experimental studies have questioned its efficacy. The purpose of this study was to evaluate the effects of PRP on experimental alveolar wound healing in rats. Fifty young adult male Wistar rats were divided in control and PRP groups and submitted to extraction of the right maxillary incisor. In the PRP group, blood was collected by cardiac puncture, and the socket was filled with a PRP gel. Animals were euthanized after 1, 3, 7, 14 and 30 days. Histological and histomorphometric analyses were performed at each experimental time point. Semiquantitative histological analysis showed that the PRP group exhibited significantly more collagen-matrix deposition and less bone-matrix formation in the socket than did the control group from 7 to 30 days. Histomorphometric analyses showed that the PRP group also exhibited lower bone-tissue areas than the control group at 7 (p=0.0250) and 14 days (p<0.0001), but at 30 days, no significant difference between the groups was observed. In the present study, PRP did not enhance alveolar wound healing, and PRP-treated rats exhibited low rates of bone deposition during the intermediate phases of alveolar socket repair.

Las opiniones sobre la utilidad clínica del plasma rico en plaquetas (PRP) varían, ya que un gran número de estudios experimentales han cuestionado su eficacia. El propósito de este estudio fue evaluar los efectos del PRP sobre la cicatrización experimental de heridas alveolares en ratas. Cincuenta ratas Wistar adultas fueron divididas en grupos control y PRP, y fueron sometidas a extracción del incisivo maxilar derecho. En el grupo de PRP, la sangre se recogió por punción cardiaca, y el alvéolo se llenó con un gel de PRP. Los animales se sacrificaron después de 1, 3, 7, 14 y 30 días. Se realizaron análisis histológicos e histomorfométricos en cada momento experimental. El análisis histológico semicuantitativo mostró que el grupo de PRP exhibió significativamente más deposición de matriz de colágeno y menos formación de matriz ósea en el receptáculo que el grupo control de 7 a 30 días. Los análisis histomorfométricos mostraron que el grupo PRP también exhibió áreas de tejido óseo inferiores al grupo control a 7 (p = 0,0250) y 14 días (p <0,0001), pero a los 30 días no se observó diferencia significativa entre los grupos. En el presente estudio, el PRP no mejoró la cicatrización de las heridas alveolares, y las ratas tratadas con PRP mostraron bajas tasas de deposición ósea durante las fases intermedias de la reparación de los receptáculos alveolares.

Classification of the anatomical structures of maxillary central incisor root by cone-beam CT / 中华口腔医学杂志

Objective@#To examine the root position of the maxillary central incisors and to provide clinical reference before the immediate implant placement.@*Methods@#Cone-beam CT (CBCT) data of the maxillary central incisors of 934 patients (934 incisors) was selected and the root position classsified. The sagittal root position in the alveolar bone was classified as buccal, middle, or palatal. The buccally positoined type was further classified into three subtypes of Ⅰ,Ⅱ, and Ⅲ.@*Results@#Most of the maxillary incisor root (95.4% [891/934]) was positioned buccally. Among the buccal-type incisors, the subtypes Ⅰ, Ⅱ and Ⅲ accounted for 47.5% (423/891), 44.2% (394/891), and 8.3% (74/891). In the 4 mm apical to the cemento-enamel junction and the middle of the root, the thickest buccal bone wall was 0.86 and 0.95 mm, the thickest palatal bone wall was 1.65 and 2.37 mm. In the apical location, the thickest buccal bone wall was 1.89 mm, the thickest palatal bone wall was 7.83 mm.@*Conclusions@#Most of the maxillary central incisors studied are positioned buccally, and half of these patients have adequate buccal bone and are suitable for immediate implant placement.

Investigation of sagittal root position in relation to the anterior maxillary alveolar bone: a cone-beam CT study in 300 cases with normal occlusion / 中华口腔医学杂志

Objective@#To investigate the sagittal root position and apical bone height of the maxillary anterior teeth in order to provide anatomical information for immediate implant placement in the esthetic region.@*Methods@#Cone-beam CT (CBCT) data from 300 randomly selected patients who met the inclusion criteria were included in this study. After three-dimensional reconstruction, the sagittal plane (the sagittal plane through the long axis of the tooth) was determined. The positions and angulations of the tooth roots were classified with reference to the alveolar process. By comparing the buccal and palatal bone thickness at the mid-root level, the toot positions with reference to the mid-alveolar line were defined and classified as follows, type B (closer to the buccal alveolar surface), type M (midway between the buccal and palatal alveolar surface) and type P (closer to the palatal alveolar surface). By comparing the angulations of the alveolar process with the long axis of the roots, the angulations were classified as follows, type 1 (root apex angulated toward the palatal side or parallel to the alveolus), type 2 (root apex angulated toward the buccal side with the long axis passing posterior to point A) and type 3 (root apex angulated toward the buccal side with the long axis passing anterior to point A). The frequency of each category was counted and the apical bone height was measured. The subjects were divided into three age groups, 19-30 years, 31-50 years and 51-75 years.@*Results@#The overall mean apical bone height of the healthy maxillary central incisors was (9.2±3.0) mm, the lateral incisors was (10.0±2.9) mm and the canine was (8.1±3.1) mm. There was no significant difference in the height of apical bone between central incisors and lateral incisors (P>0.05). There was no significant difference in the height of apical bone between male and female (P>0.05). The height of apical bone in group 31-50 years and 51-75 years were greater than that in group 19-30 years (P<0.05), respectively. The proportion of the maxillary anterior teeth type B, M, P was 98.5% (1 774/1 800), 0.3% (5/1 800) and 1.2% (21/1 800) respectively. The proportion of type 1, 2, 3 was 2.6% (46/1 800), 58.6% (1 055/1 800) and 38.8% (699/1 800) respectively.@*Conclusions@#There was enough apical bone height in the area of maxillary anterior teeth, but the majority of roots positioned more buccally.

Comparative, randomized, double-blind clinical study of alveolar ridge preservation using an extracellular matrix-based dental resorbable membrane in the extraction socket

PURPOSE: The aim of this study was to radiographically and clinically compare the effect of extracellular matrix (ECM) membranes on dimensional alterations following a ridge preservation procedure. METHODS: One of 2 different ECM membranes was applied during a ridge preservation procedure. A widely used ECM membrane (WEM; Bio-Gide, Geistlich Biomaterials, Wolhusen, Switzerland) was applied in the treatment group and a newly developed ECM membrane (NEM; Lyso-Gide, Oscotec Inc., Seongnam, Korea) was applied in the control group. Cone-beam computed tomography (CBCT) scans and alginate impressions were obtained 1 week and 6 months after the ridge preservation procedure. Results were analyzed using the independent t-test and the nonparametric Mann-Whitney U test. RESULTS: There were no significant differences between the ECM membranes in the changes in the dimension, width, and height of the extraction socket or the quantity of bone tissue. CONCLUSIONS: The NEM showed comparable clinical and radiographic results to the WEM following the ridge preservation procedure.