Inferior Alveolar Nerve Lateralization Surgery for Implant Installation in Atrophic Posterior Mandible With Accessory Mental Foramen: A Challenge for the Usual Technique.

ABSTRACT: Implantology allows edentulous patients to smile and chew with confidence. However, the atrophy at posterior region of the mandible is still a challenge due the presence of the inferior alveolar nerve (iAN). The options of restoration with oral implants in this area with great atrophies are few and hazardous. The possibilities are: bone grafting, short implants, which are not always possible. So, the solution falls on the techniques of inferior alveolar nerve lateralization (IANL) or transposition. The knowledge of the anatomy and path of the IAN is decisive in this type of surgery. But anatomical variations may occur. Like the presence of an accessory mental foramen. This clinical study will present a relatively rare case of the occurrence of an accessory mental foramen that obliged to change the technique of iAN lateralization to contour this anatomical variance and install oral implants, maintaining the integrity of the iAN bundle.

Histologic Evaluation of Early Bone Regeneration Treated with Simvastatin Associated with Low-Level Laser Therapy.

PURPOSE: This histologic study aimed at assessing bone healing after treatment with simvastatin in association with low-level laser therapy (LLLT). METHODS: Twenty-four male rats (Wistar) were submitted to surgery to create a bone defect of 5 mm in diameter in the parietal bone. These rats were randomly and equally divided into four treatment groups (n = 6): control (C), in which no treatment was performed; simvastatin (SIM), in which rats received daily subcutaneous doses of 2.5 mg/kg of simvastatin; LLLT, which was daily applied to the bone defect; and SIM-LLLT, in which both SIM and LLLT were daily applied. All laser irradiations were carried out with a 830-nm infrared diode laser (GaAlAs) with maximum output of 100 mW and a dose of 4 J, totaling 16 J per session. Rats were euthanized on the 12th postoperative day. Formalin-fixed paraffin-embedded bone samples were obtained and stained with hematoxylin-eosin (HE) and toluidine blue for optical microscope analysis. Degree of inflammation, new vascular formation, tissue repair, and osteoblastic activity were assessed. RESULTS: Categorical analysis of the histologic slides revealed newly formed bone reaching the center of the surgical wound in two animals from the SIM group, two from the LLLT group, and three from the SIM-LLLT group. Greater new bone formation and a lower degree of inflammation were observed in the animals that had bone neoformation at the center of the defect, especially in the LLLT and SIM-LLLT groups. SIM and C groups presented greater angiogenesis than LLLT and SIM-LLLT. SIMLLLT therapy showed a statistically significant reduction in the degree of inflammation when compared to the control group (P < .05). CONCLUSION: Within the limitations of this study, the present results suggest that a combination of simvastatin and low-level laser therapy may stimulate better bone formation.

Analysis of Trauma Intensity during Surgical Bone Procedures Using NF-κB Expression Levels as a Stress Sensor: An Experimental Study in a Wistar Rat Model.

Aim and objectives: It is well known that the transcription factor NF-κB regulates multiple aspects of innate and adaptive immune functions and functions as a pivotal mediator of inflammatory responses. In the present study, we evaluated the trauma generated (inflammatory reaction) after osteotomy bone surgical procedures and placement of implants in the femoral cortical bone of Wistar rats. Surgical stress was evaluated measuring the release and activation of the NF-κB factor. Materials and Methods: Rats were divided into four groups (n = 10) and submitted to different surgical treatments: Control Group (G1 group), only bone perforation was performed without irrigation; Implant Group (G2 group), a titanium implant was inserted after bone perforation without irrigation; Irrigated Group (G3 group) perforations were performed with intense irrigation; and Vitaminic Compound Group (G4 group) surgical perforation was performed without irrigation and a vitaminic compound containing the principal ions present in the natural bone structure was used to fill the bone defect. All animals were euthanized six hours after the surgical procedure and NF-κB levels were determined through immunohistochemical stain followed by direct counting of labeled and unlabeled osteocytes. Results: Among different treated groups, the overall mean of the NF-κB positive cell count in all positions were higher for G1 group (33.4 ± 2.45 cells). NF-κB values were lower in the G2 group (28.9 ± 2.70 cells), whereas in the G3 group (24.3 ± 2.72 cells) as well as in G4 group still lesser NF-κB positive cells were counted (26.5 ± 2.60 cells). Conclusions: The results here presented suggest that maneuvers performed during osteotomy procedures can significantly affect inflammation levels. The NF-κB activation during the surgical procedures can be minimized and/or controlled thought the adequate irrigation or application of adequate substances.

Comparative Study on the Cutting Effectiveness and Heat Generation of Rotary Instruments Versus Piezoelectric Surgery Tips Using Scanning Electron Microscopy and Thermal Analysis.

PURPOSE: The search for optimizing rehabilitation results with the use of osseointegrated implants has led oral surgeons to look for other technologies that can provide better predictability for treatments; however, effectiveness must be considered as well. This study aimed to compare temperature variation during preparation of implant surgical beds using conventional rotary implant burs versus ultrasonic tips and to study perforation effectiveness by analyzing the functional wear of both systems and the influence of such wear on the overheating of cortical bone. MATERIALS AND METHODS: This evaluation was made using thermocouples placed in fresh bovine cortical bone (femur) and connected to a data collector so that the recorded temperatures could provide the thermal behavior of both systems after repeated use of the burs and piezoelectric tips, to compare the wear and the loss of cutting efficiency. Scanning electron microscopy (SEM) was used to compare the topography of both systems' perforations. Biostatistics assays were performed comparing both techniques as well. RESULTS: The collected data and images showed that the wear of the burs and tips did not significantly influence the temperature variation, and the greatest variation occurred in the piezoelectric system for preparations of 13-mm depth. The SEM images show a different surface topography between both systems. While the burs cut the bone, showing a smooth surface, the piezoelectric tips condense the bone and present a rough surface. CONCLUSION: The use of either rotatory burs or piezoelectric tips generates a temperature that does not affect the tissue healing. Burs create a smooth surface, and piezoelectric tips show a more rough and condensed bone surface. The wear of both systems does not have a relevant increase in temperature after the preparation of 30 surgical beds.

Computed Tomographic Artifacts in Maxillofacial Surgery.

OBJECTIVES: The present study aimed to present 4 cases and to undertake a systematic review on the current knowledge of the impact of cone beam computed tomographic (CBCT) artifacts on oral and maxillofacial surgical planning and follow-up. METHODS: The MEDLINE (PubMed) database was searched for the period from February 2004 to February 2017, for studies on the impact of CBCT artifacts on surgical planning of oral and maxillofacial surgeries. The PRISMA statement was followed during data assessment and extraction. As a result, data extraction included information regarding: the use of CBCT to plan or follow-up oral and maxillofacial surgeries, presence and type identification of a CBCT artifact, and details on the impact of artifacts on image quality and/or surgical planning. Four cases were selected to illustrate the topic. RESULTS: The search strategy yielded 408 publications in MEDLINE (PubMed). An initial screening of the publications was performed using abstracts and key words. After application of exclusion criteria, a total of 11 studies were finally identified as eligible to be discussed. Studies revealed 3 main types of artifact: beam hardening, streak, and motion artifacts. Most of the studies suggest that artifacts significantly affect oral and maxillofacial surgical planning and follow-up, despite of allowing for identification of metal projectiles in cases of maxillofacial trauma. CONCLUSION: CBCT artifacts have a significant impact on oral and maxillofacial surgical planning and follow-up.

Hydroxyapatite Dome for Bone Neoformation in Rabbit Tibia.

PURPOSE: To evaluate supracortical bone neoformation with the use of hydroxyapatite (HA) hollow domes specially manufactured for osteogenesis promotion. MATERIALS AND METHODS: Nine New Zealand rabbits were selected and 18 domes were placed, divided into three groups according to the filler: control (blood clot), vitamin complex, and particulate ß-tricalcium phosphate (ß-TCP). The healing period was 8 weeks, hence fluorescent markers were applied. After healing, the samples were embedded in resin to prepare slides for light and fluorescence microscopic evaluation of the amount of neoformed bone tissue. Energy dispersive spectroscopy was also used for chemical analysis of the material inside the domes. RESULTS: The quality of neoformed bone tissue with active bone remodeling areas was observed. As a filler, ß-TCP showed higher bone formation (14.1%), better quality of neoformed bone tissue with organized structures, and an area of mineralized tissue in the dome. Bone neoformation inside the dome filled with blood clot confirmed the osteoconductive property of HA, as indicated by the migration of osteogenic cells from the blood clot, without the action of another biomaterial (mean area of bone formation for blood clot filler = 7.5%). Bone neoformation was not favored in samples filled with vitamin complex because of the difficulty of blood penetration through the material. CONCLUSION: HA domes performed well as a scaffold for bone neoformation over the cortical bone of rabbits, and this is based on maintenance of good stability and good integration with bone tissue. ß-TCP presented higher values of neoformed bone area compared with the blood clot. HA domes have osteoconductive properties, especially when filled with blood clot, because of the migration of osteogenic cells without action of any other biomaterial. In domes filled with vitamin complex, no bone formation was noted because of the absence of resorption.

Evaluating Nuclear Factor NF-κB Activation following Bone Trauma: A Pilot Study in a Wistar Rats Model.

The present study investigated the moment of peak NF-kB activation and its dissipation in the cortical bone in the femur of Wistar rat stimulated by surgical trauma. Sixty-five Wistar rats were divided into 13 groups (n = 5 per group): eight experimental groups (expG 1-8) divided based on the euthanasia time point (zero, 1 h, 2 h, 4 h, 6 h, 8 h, 12 h and 24 h) and five sham control groups (conG 1-5) killed at zero, 1 h, 2 h, 4 h and 6 h, respectively. A 1.8-mm-diameter defect was generated 0.5 mm from the femur proximal joint using a round bur to induce the surgical trauma. Overall, the activation peak of NF-κB in the cortical bone was 6 h (expG5 group) independent of the evaluated position; this peak was significantly different compared to those in the other groups (p < 0.05). The surgical trauma resulted in a spread of immune markings throughout the cortical bone with an accentuation in the knee region. The present study provides the first evidence that the NF-κB activation peak was established after 6 hours in the cortical bone of Wistar rats. The signs from a surgical trauma can span the entire cortical bone and are not limited to the damaged region.

Maniobras quirúrgicas en la extracción del tercer molar evitando problemas postoperatorios: cirugía piezoeléctrica y aplicación de un compuesto multivitamínico / Surgical maneuvers in the third molar extraction avoiding postoperative problems: piezoelectric surgery and application of a multivitamin complex

La extracción de los terceros molares mandibulares es un procedimiento de rutina en cirugía maxilofacial, realizado de forma preventiva o asociada a una condición patológica existente y puede resultar en accidentes y complicaciones. Este estudio informa de un caso de extracción de tercer molar atípica, con hipercementosis, con proximidad con el nervio dentario inferior y riesgo de fractura mandibular, lo que complica la extracción quirúrgica. Para la extracción se utilizó piezocirugía asociada la exposición del conjunto de nervios a un compuesto multivitamínico para minimizar las secuelas neuronales consecuencia de la manipulación del nervio dentario inferior. La técnica utilizada en la lateralización del nervio dentario inferior se adaptó a las necesidades de extracción del tercer molar, resultando en la preservación de la sensibilidad del mentón...

The extraction of third molars in the mandible, is a routine procedure of the maxillofacial surgeons, performed preventively or associated with an existing pathological condition. It can result in accidents and complications, this study reports a case of atypical extraction of third molar, with hypercementosis, with a proximity to the inferior alveolar nerve, and the risk of mandibular fracture, complicating the surgical extraction. Piezosurgery device was used for extraction and after exposure multivitamin compound nerve bundle associated to minimize neural sequelae forward to handling the inferior alveolar nerve. The technique used in the lateralization of the inferior alveolar nerve, adapted to the needs of third molar extraction, resulted in the preservation of the sensitivity of the chin...

Comparison between a piezoelectric device and rotary instruments in implant site preparation: an in vivo morphological, histological analysis using pigs / Comparação entre o sistema piezoelétrico e fresas na preparação de nichos para implantes: análise morfológica tecidual in vivo em suínos

OBJECTIVE: To carry out a histological comparison, at different postoperative periods, of bone tissue repair after implant site preparations on the tibia of pigs using both a piezoelectric device and rotary instruments. METHODS: Surgical procedures were performed on the tibia of four pigs. Five perforations were made in the left tibia using star shaped piezosurgery tips (Piezosonic Driller(r)) and five perforations in the right tibia using carbon coated rotary drills (DSP Biomedical(r)). The pigs were then sacrificed at 2, 7, 14, and 28 days. The tibiae were removed and the tissues were prepared for histological processing and analysis under a light microscope. RESULTS: The histological analyses showed similar results at 2 days and both groups presented inflammatory infiltrate. At 7 days, the drill system produces a regular surface preparation and the process of bone repair was greater when compared with the piezoelectric device. At 14 days the presence of new bone formation was more intense with the drill system. However, at 28 days both systems showed similar results, with the presence of an organized, newly formed bone tissue. CONCLUSION: It was possible to conclude that both implant site preparations, using the piezoelectric device and rotatory instruments, resulted in similar bone neoformation at 28 days. .

OBJETIVO: Comparar os aspectos histomorfológicos do tecido ósseo após osteotomias realizadas em tíbias de suínos com sistema piezoelétrico e instrumentos rotatórios em diferentes tempos pós-operatórios. MÉTODOS: Procedimentos cirúrgicos foram realizados em tíbias de quatro suínos, sendo que cada animal recebeu cinco perfurações na tíbia esquerda utilizando sistema piezoelétrico com pontas em forma de estrela (Piezosonic Driller(r)) e cinco perfurações na tíbia direita utilizando fresas rotatórias com revestimento de carbono(DSP Biomedical(r)). Os animais foram sacrificados nos tempos pós-operatórios de 2, 7, 14 e 28 dias. As tíbias foram removidas e o material foi processado para exame histológico em microscopia de luz. RESULTADOS: Ao exame histológico, observou-se após 2 dias, achados semelhantes para os 2 grupos, revelando a presença de tecido compatível com um coágulo junto a um infiltrado inflamatório no leito osteotomizado. Aos sete dias, os preparos realizados com fresas se mostraram mais regulares e houve sinais de maior neoformação óssea próxima ao tecido ósseo remanescente quando comparados ao sistema piezoelétrico. No grupo de 14 dias ficou evidente maior neoformação óssea ao longo de todo leito cirúrgico no grupo de fresas, enquanto o sistema piezoelétrico apresentou neoformação óssea dispersa, porém ao final de 28 dias, a análise morfológica tecidual foi semelhante em ambos os grupos, com a presença de trabeculado ósseo reorganizado. CONCLUSÃO: Pode-se concluir que os achados da análise morfológica revelaram que tanto o sistema piezoelétrico como as fresas na preparação de nichos para implantes promoveram neoformação óssea semelhante, evidenciando a presença de trabeculado ósseo reorganizado aos 28 dias. .

An alternative to nerve repair using an antioxidant compound: a histological study in rats.

The fascicular composition and organisation of the inferior alveolar nerve (IAN) were determined to confirm the microarchitecture of the IAN bundles into each of the mandibular teeth, including the composition of the mental nerve. The aim of this study was to evaluate peripheral nerve repair after the application of an antioxidant compound to the damaged nerve tissue to elevate the concentration and bioavailability of elements capable of favouring tissue repair. Twenty-five Wistar rats were divided into groups: The Control 1 (Ctl 1) (n = 5) animals had the ischiatic nerve exposed with no suture injury and were sacrificed at 30 days post-operatively. The Control 2 (Ctl 2) (n = 10) animals had the ischiatic nerve exposed, and the nerve was injured using suture in three distinct regions. In the experimental (Exp) animals (n = 10), an antioxidant organic compound was applied to the nerve injury site. The animals with nerve injury (Ctl2 and Exp group) were sacrificed at 15 and 30 days post-operatively. The histological analysis showed less degeneration in the Exp group at 15 and 30 days post-operatively. Nerve neoformation forming a connection between the distal and proximal suture sites was observed in the experimental group. This study presented an alternative to nerve repair using an antioxidant compound.

An alternative to never repair using an antioxidant compound: a histological study in rats

The fascicular composition and organisation of the inferior alveolar nerve (IAN) were determined to confirm the microarchitecture of the IAN bundles into each of the mandibular teeth, including the composition of the mental nerve. The aim of this study was to evaluate peripheral nerve repair after the application of an antioxidant compound to the damaged nerve tissue to elevate the concentration and bioavailability of elements capable of favouring tissue repair. Twenty-five Wistar rats were divided into groups: The Control 1 (Ctl 1) (n = 5) animals had the ischiatic nerve exposed with no suture injury and were sacrificed at 30 days post-operatively. The Control 2 (Ctl 2) (n = 10) animals had the ischiatic nerve exposed, and the nerve was injured using suture in three distinct regions. In the experimental (Exp) animals (n = 10), an antioxidant organic compound was applied to the nerve injury site...(AU)

Biologic response to titanium implants with laser-treated surfaces.

PURPOSE: To examine the biologic response to titanium implant surfaces treated with a neodymium:yttrium-aluminum-garnet laser. MATERIALS AND METHODS: Sixty mini-implants made of grade 2 titanium were placed in the femora of 30 Wistar rats. Thirty implants had a machined surface and the other 30 had surfaces that were roughened by laser treatment. The animals were subdivided into three groups according to bone repair periods of 15, 30, and 60 days. The samples were observed under light and electron scanning microscopes and analyzed with the Student t test. RESULTS: Formation of new bone trabeculae toward the surface was apparent for the laser-treated implants at 15 days. Thin layers of bone matrix in intimate contact with the surface in the area of the central screw threads were observed, indicating high biocompatibility. Similar results were seen with machined implants after 30 days. A significant difference in bone formation was observed between the implant types at 15 days. CONCLUSION: Bone-to-implant contact was better on the surfaces subjected to laser treatment than on the machined titanium implants. The development of new laser treatments, which promote alterations in the surface energy as well as in the macro- and microstructures of titanium, may lead to improved bone-to-implant contact and thus better outcomes.

Uma nova proposta de reversão da parestesia em lateralização de nervo alveolar inferior / A new proposed reversal of paresthesia in lateralization of the inferior alveolar nerve

A cirurgia de lateralização do nervo alveolar inferior se apresenta como uma alternativa para tratamento de mandíbulas atróficas, mas enfrenta como obstáculo à técnica a incidência da parestesia. Este trabalho objetivou relatar um caso clínico da técnica de lateralização de nervo alveolar inferior com instalação de implantes dentais, associada ao uso de instrumento piezoelétrico, laserterapia e de um composto polivitamínico com regressão da média da duração da parestesia baseado em achados científicos prévios. Esta nova metodologia foi desenvolvida a partir de observação clínica ao longo dos anos, que levou a pesquisas laboratoriais in vitro e in vivo no Instituto de Ciências Biomédicas da USP e no Centro de Ciências e Tecnologia de Materiais do Ipen-USP, que culminaram em teses de doutoramento e pós-doutoramento, antes de ser aplicadas em clínica, sempre visando uma melhoria na qualidade de vida dos pacientes. Os resultados clínicos demonstrados no presente trabalho estão de acordo com os achados laboratoriais, confirmando as pesquisas e levando a uma nova perspectiva na utilização da técnica e na regressão do dano neurossensor.

The surgical procedure of inferior alveolar nerve lateralization is an alternative treatment for atrophic mandibles but a potential drawback in this technique is the incidence of paresthesia. The purpose of this work is to present a case report of inferior alveolar nerve lateralization for dental implants insertion using piezoelectric device, lasertherapy and a polyvitaminic compound to reduce the rate of paresthesia endurance based on previous scientifi c data. This new methodology was developed by long-term clinical observation and led to the development of in vitro and in vivo laboratory research that took place at Instituto de Ciências Biomédicas, USP and at the Centro de Ciências e Tecnologia de Materiais at Ipen-USP, resulting in a PhD thesis and post-doctoral thesis, before clinical trials, always aiming the improvement of quality of human life. Clinical results shown in this work are consonant to those found in laboratory and leads to a new perspective on the surgical technique and neurosensory impairment regression.

Morfologia de implantes dentários com superfície tratada a laser: análise in vivo / Morphology of laser-treated dental implant surfaces: in vivo analysis

Rugosidades criadas em superfícies de implantes de titânio promovem alterações morfológicas que podem favorecer o contato osso/implante. A energia superficial resultante de jateamento com partículas, ataque químico e tratamento por oxidação anódica na superfície dos implantes promove mudanças na resposta das células ósseas. O objetivo deste estudo foi avaliar a resposta do tecido ósseo na superfície de implantes tratados sob irradiação a laser (Nd: YAG). Os implantes submetidos a este método foram analisados sob microscopia eletrônica de varredura (MEV) e confocal 3D, além de avaliação superficial por equipamento de rugosímetro. Foram instalados, em fêmures de ratos Wistar, 30 mini-implantes com tratamento superficial a laser, e confeccionados em titânio grau II. Os animais foram divididos em três grupos, de acordo com os períodos de reparação óssea – 15, 30 e 60 dias. As amostras foram analisadas sob microscopia de luz e MEV. Os resultados demonstraram formação de depósitos de nova matriz óssea preenchidos por pequenas quantidades de fibras colágenas II e III, no grupo 15 dias. Finas camadas de matriz óssea e osteoide em íntimo contato com a superfície das espiras centrais foram identificadas (30 dias), indicando elevada biocompatibilidade. Após 60 dias, o tecido ósseo mostrou características biológicas de maturidade e contato com a superfície. A porosidade superficial com média de 40 µm e profundidade com 5,3 µm demonstrou ser favorável à deposição óssea. O desenvolvimento de novas superfícies tratadas com equipamento a laser promovendo mudanças na energia superficial, assim como a macro e microestruturas, pode estimular novos estudos para o futuro da Implantodontia.

Roughness created implant titanium surfaces promote morphological alterations that may promote bone/implant contact. The surface energy resulting from blasting with particles, chemical attack and treatment by anodic oxidation on implant surfaces, promotes changes in the response of bone cells. The objective of this study was to evaluate the response of bone tissue on the implant surfaces treated under laser irradiation (Nd: YAG). The implants submitted to this method were examined under scanning electron microscopy (SEM), confocal 3-D and superficial evaluation by roughness tester equipment. Thirty mini-implants with superficial laser treatment and made in cp titanium grade II, were installed in Wistar rat femur. The animals were divided into three groups according to the periods of bone repair (15, 30 and 60 days). The samples were examined under light microscopy and SEM. The results demonstrated formation of new bone matrix filled with small amounts of collagen fibers II and III (15 days). Thin layers of bone and osteoid matrix in intimate contact with the surface of central threads were identified (30 days), indicating high biocompatibility. After 60 days the bone tissue showed biological characteristics of maturity and contact with the surface. The porosity surface with an average of 40 µm and depth with 5.3 µm proved to be favorable for bone deposition. The development of new areas treated with laser equipment, promoting changes in surface energy as well as the macro and microstructures, can stimulate new studies for the future of implantology.

Guiando o processo de reparo ósseo com a utilização de composto orgânico polivitamínico / Guiding the bone repair process using a multivitamin organic substance

Várias citocinas estão presentes durante o processo inflamatório/reparativo, sendo muitas delas também encontradas na organogênese. O objetivo desse estudo foi avaliar a possibilidade de aproveitar as condições iniciais do processo de reparo e dirigir as citocinas para a formação de um tecido organizado. Para esse estudo foram utilizados sete cães sem raça definida, nos quais foram instalados 56 implantes, sendo oito em cada animal (dois em cada tíbia e dois em cada hemimandíbula). Os grupos foram elaborados da seguinte maneira: grupo controle (um animal), onde foram somente inseridos os implantes, com o preparo do leito de forma convencional; grupo experimental 1 (Exp1), onde foram inseridos os implantes em leitos preparados com a fresagem até 4,5 mm de diâmetro e o espaço preenchido pelo material polimérico; grupo experimental 2 (Exp2), onde foram inseridos os implantes em leitos preparados com a fresagem até 4,5 mm de diâmetro e o espaço preenchido pelo material polimérico acrescido do composto orgânico, em proporção de 30% do peso do polímero (três animais). Os resultados indicaram um aumento da neoformação óssea local e um incremento na velocidade da deposição óssea, verificada principalmente na região supracortical, nos animais do grupo Exp2, diferentemente do grupo Exp1, onde não houve a neoformação óssea e os implantes não apresentaram osseointegração. Concluiu-se, com base nos resultados, que houve produção endógena de BMPs pelas células locais que ficaram isoladas, sugerindo que uma composição de elementos orgânicos e inorgânicos pode direcionar o tecido lesado para uma neoformação óssea organizada.

Several cytokines are present during the inflammatory/repair process, many of which are also found in organogenesis. The aim of this study was to evaluate the possibility to take the initial conditions of the repair process and guide cytokines to form an organized tissue. Seven mongrel dogs were used in this study (56 implants installed, 8 in each animal, being two in each tibia and two in each hemi-mandible). Groups were prepared as follows: Control group (one animal), with the implants inserted using a conventional preparation technique; Experimental group 1 (Exp1), with the implants inserted into sites prepared with a 4.5 mm-drill and the space filled by polymeric material; Experimental group 2 (Exp2), with the same technique in Exp1 plus the organic compound (30% by weight, three animals). The results indicated an increase in local bone formation and an increase in the speed of bone deposition, seen mainly at the cortex of group Exp2. No new bone formation and osseointegration were seen in Group Exp1. It was concluded that there was an isolated, endogenous production of BMPs by local cells suggesting that a composition of organic and inorganic elements can direct the injured tissue to an organized bone formation.

Identification of the nuclear factor kappa-beta (NF-kB) in cortical of mice Wistar using Technovit 7200 VCR®.

OBJECTIVE: this study aimed to develop a nondecalcified bone sample processing technique enabling immunohistochemical labeling of proteins by kappa-beta nuclear factor (NF-kB) utilizing the Technovit 7200 VCR® in adult male Wistar rats. STUDY METHOD: A 1.8 mm diameter defect was performed 0.5 mm from the femur proximal joint by means of a round bur. Experimental groups were divided according to fixing solution prior to histologic processing: Group 1--ethanol 70%; Group 2--10% buffered formalin; and Group 3--Glycerol diluted in 70% ethanol at a 70/30 ratio + 10% buffered formalin. The post-surgical periods ranged from 01 to 24 hours. Control groups included a non-surgical procedure group (NSPG) and surgical procedures where bone exposure was performed (SPBE) without drilling. Prostate carcinoma was the positive control (PC) and samples subjected to incomplete immunohistochemistry protocol were the negative control (NC). Following euthanization, all samples were kept at 4°C for 7 days, and were dehydrated in a series of alcohols at -20°C. The polymer embedding procedure was performed at ethanol/polymer ratios of 70%-30%, 50%-50%, 30%-70%, 100%, and 100% for 72 hours at -20°C. Polymerization followed the manufacturer's recommendation. The samples were grounded and polished to 10-15 m thickness, and were deacrylated. The sections were rehydrated and were submitted to the primary polyclonal antibody anti-NF-kB on a 1:75 dilution for 12 hours at room temperature. RESULTS: Microscopy showed that the Group 2 presented positive reaction to NF-kB, diffuse reactions for NSPG and SPBE, and no reaction for the NC group. CONCLUSION: The results obtained support the feasibility of the developed immunohistochemistry technique.

Implantes temporários em caráter definitivo: uma alternativa social / Long-term use of temporary dental implants: a social alternative

A Implantodontia experimentou grandes avanços ao longo de mais de 40 anos quando o professor Brånemark orientou a primeira cirurgia em paciente, definindo o conceito da Osseointegração. Desde então, observou-se novas metodologias como carga imediata, all on four, implantes zigomáticos, cirurgias guiadas por computador e outras inovações. Entretanto, o procedimento cirúrgico em si continua cirurgicamente traumático e economicamente inacessível para certas camadas da população. Neste contexto, este trabalho objetivou relatar três casos clínicos com a utilização de implantes temporários em caráter definitivo para estabilização imediata de prótese total inferior, diminuindo o trauma cirúrgico e o custo do tratamento, devolvendo a segurança e a confiança de pacientes totalmente edêntulos imediatamente após a instalação dos implantes.

Implantology has experienced a great technological advance in the latest 40 years since Professor Brånemark oriented the first surgical procedure in a patient defining the concept of Osseointegration. Since then, new methodologies as immediate loading, the "All-on-four" concept, zygomatic fixations, computer-guided surgery and other innovations have been presented. However, the surgical procedure itself remains traumatic and economically not available to certain patients. This article aims to relate three clinical situations with temporary implants used as long-term implants for immediate stabilization of inferior full denture prostheses, diminishing surgical trauma and treatment costs, reestablishing confidence to completely edentulous patients immediately after the implant placement.

Microstructural and ultrastructural assessment of inferior alveolar nerve damage following nerve lateralization and implant placement: an experimental study in rabbits.

PURPOSE: The present study assessed damage to the inferior alveolar nerve (IAN) following nerve lateralization and implant placement surgery through optical and transmission electron microscopy (TEM). MATERIALS AND METHODS: IAN lateralization was performed in 16 adult female rabbits (Oryctolagus cuniculus). During the nerve lateralization procedure, one implant was placed through the mandibular canal, and the IAN was replaced in direct contact with the implant. The implant was placed in the right mandible, and the left side was used as a control (no surgical procedure). After 8 weeks, the animals were sacrificed and samples were prepared for optical and TEM analysis of IAN structural damage. Histomorphometric analysis was performed to determine the number and cross-sectional dimensions of nerve fascicles and myelin sheath thickness between experimental and control groups. The different parameters were compared by one-way analysis of variance at the 95% significance level. RESULTS: Alterations in the perineural and endoneural regions of the IAN, with higher degrees of vascularization, were observed in the experimental group. TEM showed that the majority of the myelinated nerve fibers were not affected in the experimental samples. No significant variation in the number of fascicles was observed, significantly larger fascicle height and width were observed in the control group, and significantly thicker myelin sheaths were observed in the experimental samples. CONCLUSION: IAN lateralization resulted in substantial degrees of tissue disorganization at the microstructural level because of the presence of edema. However, at the ultrastructural level, small amounts of fiber degeneration were observed.

Uma nova proposta de reversão da parestesia em lateralização de nervo alveolar inferior / Piezosurgery associated to laserterapy and vitamin compounds for paresthesia reversal after inferior alveolar nerve lateralization - a case report

A cirurgia de lateralização do nervo alveolar inferior se apresenta como uma alternativa para tratamento de mandíbulas atróficas, mas enfrenta como obstáculo à técnica a incidência da parestesia. Este trabalho objetiva relatar um caso clínico da técnica de lateralização de nervo alveolar inferior com instalação de implantes dentais, associada ao uso de instrumento piezoelétrico, laserterapia e de um composto polivitamínico com regressão da média da duração da parestesia baseado em achados científicos prévios. Esta nova metodologia foi desenvolvida a partir de observação clínica ao longo dos anos que levaram a pesquisas laboratoriais in vitro e in vivo no Instituto de Ciências Biomédicas da USP e no Centro de Ciências e Tecnologia de Materiais do Ipen-USP, que culminaram em teses de doutoramento e pós-doutoramento, antes de ser aplicadas em clínica, sempre visando uma melhoria na qualidade de vida dos pacientes. Os resultados clínicos demonstrados no presente trabalho estão de acordo com os achados laboratoriais confirmando as pesquisas e levam a uma nova perspectiva na utilização da técnica e na regressão do dano neurossensor.

A light and scanning electron microscopy study of bone healing following inferior alveolar nerve lateralization: an experimental study in rabbits.

PURPOSE: The purpose of this study was to evaluate the bone healing kinetics around commercially pure titanium implants following inferior alveolar nerve (IAN) lateralization in a rabbit model. MATERIALS AND METHODS: Inferior alveolar nerve lateralization was performed in 16 adult female rabbits (Oryctolagus cuniculus). During the nerve lateralization procedure, 1 implant was placed through the mandibular canal, and the IAN was replaced in direct contact with the implant. During the 8-week healing period, various bone labels were administered for fluorescent microscopy analysis. The animals were euthanized by anesthesia overdose, and the mandibular blocks were exposed by sharp dissection. Nondecalcified samples were prepared for optical light and scanning electron microscopy (SEM) evaluation. RESULTS: SEM evaluation showed bone modeling/remodeling between the IAN and implant surface. Fluorochrome area fraction labeling at different times during the healing period showed that bone apposition mainly occurred during the first 2 weeks after implantation. CONCLUSIONS: The results obtained showed that bone healing/deposition occurred between the alveolar nerves in contact with a commercially pure titanium implant. No interaction between the nerve and the implant was detected after the 8-week healing period. Appositional bone healing occurred around the nerve bundle structure, restoring the mandibular canal integrity and morphology.