Experimental toothpastes containing ß-TCP nanoparticles functionalized with fluoride and tin to prevent Erosive Tooth Wear.

OBJECTIVES: The present study aimed to synthesize toothpastes containing Beta- TriCalcium Phosphate (ß-TCP) nanoparticles, functionalized with fluoride and tin, and test their ability to reduce erosive tooth wear (ETW). METHODS: Toothpastes were synthesized with the following active ingredients: 1100 ppm of fluoride (as sodium fluoride, F-), 3500 ppm of tin (as stannous chloride, Sn2+), and 800 ppm of ß-TCP (Sizes a - 20 nm; and b - 100 nm). Enamel specimens were randomly assigned into the following groups (n = 10): 1. Commercial toothpaste; 2. Placebo; 3 F-; 4. F- + ß-TCPa; 5. F- + ß-TCPb; 6. F- + Sn2+; 7. F- + Sn2+ + ß-TCPa and 8. F- + Sn2+ + ß-TCPb. Specimens were subjected to erosion-abrasion cycling. Surface loss (in µm) was measured by optical profilometry. Toothpastes pH and available F- were also assessed. RESULTS: Brushing with placebo toothpaste resulted in higher surface loss than brushing with F- (p = 0.005) and F- + ß-TCPb (p = 0.007); however, there was no difference between F- and F- + ß-TCPb (p = 1.00). Commercial toothpaste showed no difference from Placebo (p = 0.279). The groups F-, F- + ß-TCPa, F- + ß-TCPb, F- + Sn2+, F- + Sn2+ + ß-TCPa and F- + Sn2+ + ß-TCPb were not different from the commercial toothpaste (p > 0.05). Overall, the addition of ß-TCP reduced the amount of available fluoride in the experimental toothpastes. The pH of toothpastes ranged from 4.97 to 6.49. CONCLUSIONS: Although toothpaste containing ß-TCP nanoparticles protected enamel against dental erosion-abrasion, this effect was not superior to the standard fluoride toothpaste (commercial). In addition, the functionalization of ß-TCP nanoparticles with fluoride and tin did not enhance their protective effect. CLINICAL SIGNIFICANCE: Although ß-TCP nanoparticles have some potential to control Erosive Tooth Wear, their incorporation into an experimental toothpaste appears to have a protective effect that is similar to a commercial fluoride toothpaste.

Does Melatonin Associated with Nanostructured Calcium Phosphate Improve Alveolar Bone Repair?

Background and objectives: Calcium phosphates have been widely used as bone substitutes, but their properties are limited to osteoconduction. The association of calcium phosphates with osteoinductive bioactive molecules has been used as a strategy in regenerative medicine. Melatonin has been studied due to its cell protection and antioxidant functions, reducing osteoclastic activity and stimulating newly formed bone. This study aimed to evaluate the effect of topical application of melatonin associated with nanostructured carbonated hydroxyapatite microspheres in the alveolar bone repair of Wistar rats through histological and histomorphometric analysis. Materials and Methods: Thirty female Wistar rats (300 g) were used, divided randomly into three experimental groups (n = 10), G1: nanostructured carbonated hydroxyapatite microspheres associated with melatonin gel (CHA-M); G2: nanostructured carbonated hydroxyapatite (CHA); G3: blood clot (without alveolar filling). The animals were euthanized after 7 and 42 days of the postoperative period and processed for histological and histomorphometric evaluation. Kruskal-Wallis and Dunn's post-test were applied to investigate statistical differences between the groups at the same time point for new bone and connective tissue variables. Mann-Whitney was used to assess statistical differences between different time points and in the biomaterial variable. Results: Results showed a greater volume of residual biomaterial in the CHA-M than the CHA group (p = 0.007), and there were no significant differences in terms of newly formed bone and connective tissue between CHA and CHA-M after 42 days. Conclusions: This study concluded that both biomaterials improved alveolar bone repair from 7 to 42 days after surgery, and the association of CHA with melatonin gel reduced the biomaterial's biodegradation at the implanted site but did not improve the alveolar bone repair.

In vivo evaluation of interactions between biphasic calcium phosphate (BCP)-niobium pentoxide (Nb2O5) nanocomposite and tissues using a rat critical-size calvarial defect model.

Natural or synthetic biomaterials are increasingly being used to support bone tissue repair or substitution. The combination of natural calcium phosphates with biocompatible alloys is an important route towards the development of new biomaterials with bioperformance and mechanical responses to mimic those of human bones. This article evaluated the structural, physical, mechanical and biological properties of a new mechanical improved nanocomposite elaborated by association of fish biphasic calcium phosphate (BCP) and niobium pentoxide (Nb2O5). The nanocomposite (Nb-BCP) and the pure BCP, used as a positive control, were obtained by powder metallurgy. The density, porosity and microhardness were measured. The structural analysis was determined by X-ray diffraction (XRD) and the biological properties were studied in histological sections of critical size calvaria defects in rats, 7, 15, 30, 45 and 60 days after implantation of disks of both materials. Morphological description was made after scanning electron microscopy (SEM) and optical microscopy analysis. After sintering, the Nb-BCP nanocomposite presented four crystalline phases: 34.36% calcium niobate (CaNb2O6), 21.68% phosphorus niobium oxide (PNb9O25), 42.55% ß-tricalcium phosphate (Ca3(PO4)2) and 1.31% of niobium pentoxide (Nb2O5) and exhibited increases of 17% in density, 66% in Vickers microhardness and 180% in compressive strength compared to pure BCP. In vivo study, showed biocompatibility, bioactivity and osteoconductivity similar to pure BCP. SEM showed the formation of globular accretions over the implanted nanocomposites, representing one of the stages of bone mineralization. In conclusion, the BCP and Nb2O5 formed a nanocomposite exhibiting characteristics that are desirable for a biomaterial, such as bioperformance, higher ß-TCP percentage and improved physical and mechanical properties compared to pure BCP. These characteristics demonstrate the promise of this material for supporting bone regeneration.

Evaluation and Management of Subchondral Calcium Phosphate Injection Technique to Treat Bone Marrow Lesion.

PURPOSE: This study aimed to compile available data in medical literature about subchondral calcium phosphate injection, comparing results obtained with this technique, as well as indications, complications, and other important factors in treatment of bone marrow lesions. DESIGNS: A literature review using PubMed and Medline database in order to identify works with terms "subchondral calcium phosphate injection," " subchondroplasty®," "bone marrow lesion," and "knee." Eight relevant articles were found. RESULTS: A total of 164 patients with bone marrow lesion mainly on femoral condyle and tibial plateau recovered with significant functional improvement of knee after subchondral calcium phosphate treatment. Although 25% of them still had some type of pain complaint, they also showed improvement. There were few complications reported and return to activities occurred after 3 months on average. CONCLUSIONS: Few studies evaluate the result of using subchondral calcium phosphate injection technique. However, all presented favorable results regarding pain and improvement of knee function. In addition, within 2 years, there was a 70% reduction in conversion to total knee arthroplasty in patients with previous surgical indication who choose calcium phosphate treatment.

Histological and structural evaluation of growth hormone and PLGA incorporation in macroporous scaffold of α-tricalcium phosphate cement.

An in vivo study was conducted to evaluate the effects of the incorporation of fibers of poly(lactic acid-co-glycolic acid, PLGA) and poly(isoprene) blend and recombinant human growth hormone (rhGH) in a macroporous scaffold of α-tricalcium phosphate cement (α-TCP) samples inserted into calvarial defects (8 mm in diameter) of 48 Wistar rats. The samples of α-TCP + PLGA/poly(isoprene) blend fibers were also submitted to a mechanical test of flexural strength. The animals of the different experimental groups [1] α-TCP (n = 6); [2] α-TCP + PLGA/poly(isoprene) blend fibers (n = 6); [3] α-TCP + rhGH, (n = 6) and [4] α-TCP + PLGA/poly(isoprene) blend fibers + rhGH, (n = 6) (the numbers within square brackets identify the experimental groups), after two weeks (subdivision "a") and four weeks (subdivision "b"), were euthanized and the implants removed for histological analysis. There was no statistical difference (p > 0.05) between the samples with and without fibers in the mechanical test. Light microscopy revealed good integration of the material in the host tissue, represented by tissue penetration into the macropores and adequate angiogenesis. In the two-week period, the groups [3a] and [4a] were significantly superior (p < 0.05) to the other groups with regard to angiogenesis and bone neoformation. In the four-week period, the group [3b] was significantly superior (p < 0.05) to the other groups with regard to bone neoformation. We conclude that the macroporous α-TCP scaffold used in this study has low mechanical resistance, is biocompatible and has significantly improved the osteoconductive capacity when rhGH is incorporated into its structure.

Characterization of bone substitute beta946; -TCP block for maxillofacial reconstruction / Caracterización del bloque beta946; -TCP de sustitución ósea para la reconstrucción maxilofacial

SUMMARY: The aim of this study was to characterize a commercial beta tricalcium phosphate (β-TCP) block allograft for use in maxillofacial reconstruction, evaluating its homogeneity, porosity and mineralization. Two commercial 5 x 5 x10 mm chronOS Vivify β-TCP blocks were used, which were evaluated by a STEM SU-3500 variable pressure scanning electron microscope (SEM-STEM) (Hitachi, Japan). For the semi-quantitative microanalysis of elements, the QUANTAX 100 energy dispersive x-ray spectrometer detector (EDX) (Bruker, Germany) was used. The homogeneity of the structural morphology, macropore and micropore size and component homogeneity were evaluated. The microscopic analysis showed micropores of 164.92 mm (± 35.032 mm) in diameter in the outer area and micropores in the inner area of 54.44 mm (± 17.676 mm). The formation of porosities and irregularities present in the block was heterogeneous between the outer and inner surfaces. The mineral content of the blocks presented homogeneity with the presence of carbon (2.02 %), oxygen (44.33 %), phosphate (16.62 %) and calcium (37.87 %). The β-TCP block can be used in bone reconstruction but the presence of reduced macropore and micropore sizes could limit efficiency in the substitution and bone regeneration phase.

RESUMEN: El objetivo de este estudio fue caracterizar un aloinjerto de bloqueo de fosfato tricálcico (β-TCP) comercial para su uso en la reconstrucción maxilofacial, evaluando su homogeneidad, porosidad y mineralización. Se utilizaron dos bloques comerciales de 5 x 5 x 10 mm de vivify β-TCP de chronOS, que se evaluaron mediante un microscopio electrónico de barrido de presión variable STEM SU-3500 (SEM-STEM) (Hitachi, Japón). Para el microanálisis de elementos semicuantitativo, se utilizó el detector de espectrómetro de rayos X de dispersión de energía QUANTAX 100 (EDX) (Bruker, Alemania). Se evaluó la homogeneidad de la morfología estructural, el tamaño del macroporo y microporo y la homogeneidad de los componentes. El análisis microscópico mostró microporos de 164,92 mm (± 35,032 mm) de diámetro en el área externa y microporos en el área interna de 54,44 mm (± 17,676 mm). La formación de porosidades e irregularidades presentes en el bloque fue heterogénea entre las superficies externas e internas. El contenido mineral de los bloques presentó homogeneidad con la presencia de carbono (2,02 %), oxígeno (44,33 %), fosfato (16,62 %) y calcio (37,87 %). El bloque β-TCP se puede utilizar en la reconstrucción ósea, pero la presencia de macroporos y tamaños de microporos reducidos podría limitar la eficacia en la fase de sustitución y regeneración ósea.

CaP Coating and Low-Level Laser Therapy to Stimulate Early Bone Formation and Improve Fixation of Rough Threaded Implants.

PURPOSE: This study aimed to compare in vivo osteogenesis on rough threaded dental implants with and without calcium phosphate (CaP) coating deposition, alone or in association with low-level laser therapy (LLLT) by gallium aluminum arsenide. MATERIAL AND METHODS: Four groups were studied: G1: implant; G2: implant + CaP coating; G3: implant + LLLT; and G4: implant + CaP coating + LLLT. LLLT was applied for 7 days at the surgical site before and after placing the implant. Topographic characterization was performed before surgery using scanning electron microscopy and energy dispersion spectrophotometry. Bone-implant contact (BIC) was measured after 1, 2, and 6 weeks and reverse torque after 6 weeks. In short periods, G2, G3, and G4 showed significantly greater BIC than G1 (P < 0.05), but no difference in BIC was observed at 6 weeks. However, the values for the removal torque test at 6 weeks were higher in G2 and G4 (P < 0.05). CONCLUSION: Both CaP coating alone and using LLLT induce cellular stimulation and improve BIC in short-term healing, resulting in higher implant fixation, and should be considered in clinical practice due to their low cost and high effectiveness.

Surgical Treatment of Bone Marrow Lesion Associated with Recurrent Plantar Fasciitis: A Case Report Describing an Innovative Technique Using Subchondroplasty®.

Plantar fasciitis is one of the most common chief complaints seen in the foot and ankle clinic. With a relatively benign course, most cases are self-limiting or amendable to conservative therapy; ~90% of all plantar fasciitis cases will respond to these methods. When conservative treatment and time fail, surgical intervention can be necessary to improve outcomes. We present a novel method using Subchondroplasty® (SCP®; Zimmer Holdings, Inc.; Warsaw, IN) and revision fasciotomy in a case in which initial fasciotomy had failed. After the patient had failed to improve, a worsening underlying bone marrow lesion was identified at the origin of the plantar fascia; thus, SCP® was used with repeat fasciotomy. SCP® involves injecting calcium phosphate into bone marrow lesions to stimulate long-term bone repair. At 10 months after SCP®, the patient remained pain free and had returned to running at the final follow-up examination. This surgical treatment should be considered as an adjunctive procedure for those patients with plantar fasciitis, identifiable bone marrow lesions on magnetic resonance imaging, and continued pain when other treatment modalities have failed.

Demineralized bone matrix and calcium-phosphate cement in bone regeneration in rats

Purpose: To compare bone regeneration in critical-sized defects in rat calvarium using demineralized bone matrix and calcium phosphate cement. Methods: Thirty Wistar rats were divided into 3 groups of 10 animals each. Two defects of 5-mm were made in the parietal bones of each animal. Group I had calcium phosphate cement placed in the experimental defect, Group II had filled with demineralized bone matrix and Group III had with the combination of the matrix and cement in equal parts. All animals had one defect left unfilled to serve as controls. Five animals in each group were sacrificed at 4 and 8 weeks. Histomorphometric analysis was used to quantify the amount of new bone within the defects. Results: The results showed that demineralized bone matrix-treated defects had significantly more new bone at 4 weeks compared to calcium phosphate cement-treated defects (p=0.03) and also had significantly more new bone at 8 weeks compared to unfilled defects (p=0.04). Conclusions: The demineralized bone matrix was superior to calcium phosphate cement in bone regeneration. It seems that calcium phosphate cement acted by inhibiting the osteogenesis when associated with a demineralized bone matrix and this combination should not be recommended.(AU)

Ridge Preservation After Maxillary Third Molar Extraction Using 30% Porosity PLGA/HA/ß-TCP Scaffolds With and Without Simvastatin: A Pilot Randomized Controlled Clinical Trial.

OBJECTIVE: To evaluate clinically and radiographically, in humans, the healing of maxillary third molars postextraction sockets after application of different ridge preservation techniques 3 months after tooth extraction. MATERIALS AND METHODS: Twenty-six sockets (13 patients) were randomly assigned to 4 treatment modalities: deproteinized bovine bone mineral with 10% collagen (DBBM-C), poly(D,L-lactide-co-glycolide) with hydroxyapatite/ß-TCP scaffold (PLGA/HA), PLGA/HA/ß-TCP with 2.0% simvastatin scaffold (PLGA/HA/S), and spontaneous healing (control). Clinical complications were assessed, and cone-beam computed tomographies were taken in 5 patients 3 months after surgeries. For statistical purposes, the Fisher exact test was used (P < 0.05). RESULTS: After 3 months, 6 of 9 grafts from the PLGA/HA group were lost (P < 0.05). PLGA/HA/S' loss was only 2 of 8 (P > 0.05), but no loss was observed in the DBBM-C group. Pain was present in 3 of 8 sites that lost the graft (37.5%) (P > 0.05) and infection in 1 of 8 (12.5%) (P > 0.05), with these only occurring in the PLGA/HA group. CONCLUSIONS: Poly (D, L-lactide-co-glycolide) with hydroxyapatite/ß-TCP (PLGA/HA/ß-TCP) scaffolds, with and without simvastatin, failed to obtain the initial expected results and presented more complications. Scaffolds with simvastatin showed to be superior, with less clinical complications than scaffolds without simvastatin.

Influence of ß-tricalcium phosphate of different geometric shape on the morphology of regeneration of experimental defect of compact bone tissue / Influencia del fosfato ß-tricálcico de diferentes formas geométricas en la morfología de la regeneración del defecto experimental del tejido óseo compacto

Purpose: to compare the healing process of a defect of compact bone tissue after the implantation of osteoplastic materials based on ß-tricalcium phosphate ("ChronOS™" and "Calc-i-oss®"), which differ by manufacturer, geometrical shape and microscopic structure. Methods: the experiment was performed on 48 white male Wistar rats. In the middle third of the diaphysis of the femur we produced a perforated defect of 2.5 mm diameter in the medullary canal, which in the animals of the first group was filled with the osteoplastic material "ChronOS™" (block, Synthes, Switzerland), and in the animals of the second group with "Calc-i-oss®" (granules, «Degradable Solutions Dental¼, Switzerland). Fragments of the injured bones were studied on the 60th and 120th day by light microscopy with morphometry and by scanning electron microscopy. Results: it was found that regardless the geometric shape and the microscopic structure, both osteoplastic materials show high biocompatibility, osteoconductive properties, good integration with bone tissue of the regenerate, and that the microscopic structure of ß-tricalcium phosphate ("ChronOS™") may significantly affect the microscopic structure of bone tissue of the regenerate, which manifests itself in the specificity of its geometric shape. It was noticed that osteoplastic materials "ChronOS™" and "Calc-i-oss®" almost at the same rate were subjected to resorption and replacement by the bone tissue, the ratio of which was 22.55±1.25 to 77.45±1.25 and 25.72±2.06% to 74.28±2.06% on the 60th day of the experiment, and 17.65±1.09 to 82.35±1.09 and 18.31±1.54% to 81.69±1.54% on the 120th day. (AU)

Objetivo: Comparar el proceso de cicatrización de un defecto del tejido óseo compacto tras la implantación de materiales osteoplásticos a base de fosfato ß-tricálcico («ChronOS™¼ and «Calc-i-oss®¼) que difieren según el fabricante en la forma geométrica y estructura microscópica. El estudio fue realizado en 48 ratas Wistar machos en los cuales se produjo, en el tercio medio de la diáfisis del fémur, un defecto perforado de 2,5 mm de diámetro, el cual fue llenado con el material «ChronOS™¼ (block, Synthes, Switzerland) en un grupo y con «Calc-i-oss®¼ (granules, «Degradable Solutions Dental¼, Switzerland) en el segundo grupo. El sector del defecto fue evaluado en los días 60 y 120 por microscopía óptica y por microscopía electrónica de barrido. Resultados: independientemente de la forma geométrica y la estructura microscópica, ambos materiales osteoplásticos mostraron alta biocompatibilidad, propiedades osteoconductivas y buena integración con el tejido óseo regenerado. La estructura microscópica del fosfato ß-tricálcico («ChronOS™¼) puede afectar significativamente a la estructura microscópica del tejido óseo regenerado, que se manifiesta en su forma geométrica. Adicionalmente, se observó que ambos materiales osteoplásticos «ChronOS™¼ y «Calc-i-oss®¼ mostraron valores similares de resorción y reemplazo por tejido óseo, cuya relación al 60º día del experimento fue de 22,55±1,25 a 77,45±1,25 y 25,72±2,06% a 74,28±2,06%, y a los 120 días de 17,65±1,09 a 82,35±1,09 y de 18,31±1,54% a 81,69±1,54% respectivamente. (AU)

Repair of bone defects using adipose-derived stem cells combined with alpha-tricalcium phosphate and gelatin sponge scaffolds in a rat model.

OBJECTIVES: This study aimed to evaluate the potential of adipose-derived stem cells (ASCs) combined with a modified α-tricalcium phosphate (α-TCP) or gelatin sponge (GS) scaffolds for bone healing in a rat model. MATERIAL AND METHODS: Bone defects were surgically created in the femur of adult SHR rats and filled with the scaffolds, empty or combined with ASCs. The results were analyzed by histology and histomorphometry on days seven, 14, 30, and 60. RESULTS: Significantly increased bone repair was observed on days seven and 60 in animals treated with α-TCP/ASCs, and on day 14 in the group treated with GS/ASCs, when compared with the groups treated with the biomaterials alone. Intense fibroplasia was observed in the group treated with GS alone, on days 14 and 30. CONCLUSIONS: Our results showed that the use of ASCs combined with α-TCP or GS scaffolds resulted in increased bone repair. The higher efficacy of the α-TCP scaffold suggests osteoconductive property that results in a biological support to the cells, whereas the GS scaffold functions just as a carrier. These results confirm the potential of ASCs in accelerating bone repair in in vivo experimental rat models. These results suggest a new alternative for treating bone defects.

Repair of bone defects using adipose-derived stem cells combined with alpha-tricalcium phosphate and gelatin sponge scaffolds in a rat model

Abstract Objectives This study aimed to evaluate the potential of adipose-derived stem cells (ASCs) combined with a modified α-tricalcium phosphate (α-TCP) or gelatin sponge (GS) scaffolds for bone healing in a rat model. Material and Methods Bone defects were surgically created in the femur of adult SHR rats and filled with the scaffolds, empty or combined with ASCs. The results were analyzed by histology and histomorphometry on days seven, 14, 30, and 60. Results Significantly increased bone repair was observed on days seven and 60 in animals treated with α-TCP/ASCs, and on day 14 in the group treated with GS/ASCs, when compared with the groups treated with the biomaterials alone. Intense fibroplasia was observed in the group treated with GS alone, on days 14 and 30. Conclusions Our results showed that the use of ASCs combined with α-TCP or GS scaffolds resulted in increased bone repair. The higher efficacy of the α-TCP scaffold suggests osteoconductive property that results in a biological support to the cells, whereas the GS scaffold functions just as a carrier. These results confirm the potential of ASCs in accelerating bone repair in in vivo experimental rat models. These results suggest a new alternative for treating bone defects.

Preservación de alvéolos mediante fosfato tricálcico beta, con y sin membrana / Socket preservation using beta-tricalcium phosphate with or without membrane

El presente estudio evalúa los resultados de la utilización del fosfato tricálcico beta en la preservación de alvéolos postextracción al emplearlo solo o en conjunto con membranas no reabsorbibles. Se seleccionaron 18 dientes con indicación de extracción y con condiciones favorables para la preservación del alvéolo y posterior colocación de un implante oseointegrado. En 10 alvéolos se utilizó como relleno fosfato tricálcico beta en conjunto con membrana no reabsorbible, y 8 alvéolos fueron tratados solamente con fosfato tricálcico beta. Previo a la cirugía se evaluó el ancho y alto de cada alvéolo, mediante una tomografía computarizada de alta resolución, evaluación que fue repetida 6 meses después de realizada la intervención quirúrgica. Al momento de efectuar la técnica quirúrgica para la instalación de los implantes se tomaron muestras histológicas del sitio de colocación del implante para estudiar las características histológicas del sitio injertado después de 6 meses de realizada la cirugía de extracción dentaria y preservación de alvéolo. El uso de fosfato tricálcico beta, independiente o no del uso de membrana, mantuvo la altura del alvéolo transcurridos 6 meses desde su colocación, mientras que el ancho del alvéolo se mantuvo solo en el grupo sin membrana. Los resultados histológicos demostraron cantidades variables de regeneración ósea.

The present study evaluated the results of the post-extraction socket preservation technique using Beta-Tricalcium Phosphate with and without the use of a non-resorbable membrane. A total of 18 teeth with indication of extraction and socket preservation were selected, with 10 alveoli being treated with Beta-Tricalcium Phosphate combined with a non-resorbable membrane, and the other 8 with Beta-Tricalcium Phosphate only. The width and height of each socket was evaluated using computed tomography, prior to the extraction, and 6 months after the surgery. At the time of performing the surgical technique for installing the implants, histological specimens were taken from the implant site in order to study the graft site 6 months after the dental extraction surgery and alveoli preservation.The use of Beta-Tricalcium Phosphate, whether a membrane is used or not, maintained the alveolar height 6 months after the extraction, while the width of the alveolus only remained in the group without membrane. Histological results showed varying amounts of bone regeneration.

Reparação óssea com o uso do beta fosfato tricálcico (B-tcp)® na calota craniana de ratos submetidos ao alcoolismo experimental: análises histomorfológica e histomorfométrica / Bone repair with the use of beta tricalcium phosphate (B-TCP®) in the calvarial defect of rats submitted to experimental alcoholism: histological and morphometric analysis

O uso crônico de etanol prejudica diretamente o processo biológico de reparo ósseo, principalmente pela inibição das células osteoblásticas, podendo causar retardo de consolidação ou pseudoartrose. Vários biomateriais naturais ou sintéticos, têm sido utilizados como uma alternativa aos enxertos ósseos. Os biomateriais sintéticos, como o Beta Fosfato Tricálcico (β-TCP) são biocompatíveis, biodegradáveis e osteocondutíveis, por orientar as células osteoblásticas, promovendo a neoformação óssea. Sendo assim, objetivou-se avaliar a influência da ingestão crônica de etanol no processo de reparo ósseo de defeitos cranianos tratados com β-TCP® comparativamente aos preenchidos com coágulo sanguíneo ea sua interferência sobre a massa corporal. Foram utilizados 40 ratos machos (Rattus norvegicus), distribuídos aleatoriamente em 2 grupos: GAG – receberam água como dieta liquida, e GAL - receberam etanol a 25%. O GAL foi submetido inicialmente à adaptação gradativa ao álcool e depois permaneceu a 25% por 90dias. Após o término desse período, todos os animais foram submetidos à cirurgia experimental. Nos ossos parietais de cada animal, foram confeccionadas duas cavidades 5,0 mm de diâmetro ao lado da sutura sagital, de forma que o parietal direito foi preenchido com β-TCP® e o esquerdo com coágulo. Dessa forma, os grupos GAG e GAL foram divididos de acordo com o preenchimento dos defeitos: GC-AG (Grupo Coágulo Água), GC-AL (Grupo Coágulo Álcool), GB-AG (Grupo Biomaterial Água) e GB-AL (Grupo Biomaterial Álcool). O reparo ósseo foi observado de acordo com o período de eutanásia: 10, 20, 40 e 60 dias após a cirurgia. Após inclusão histológica, as peças foram submetidas à análises histomorfológica e histomorfométrica. Na análise da variação da massa corporal, observou-se que as massas iniciais do GAG foram maiores que GAL e as massas finais de GAG aumentou significativamente apenas em 60 dias e no GAL em todos os períodos...

Chronic use of ethanol directly affects the biological process of bone repair, primarily by inhibition of osteoblastic cells. This may cause delayed consolidation or nonunion.Various natural and synthetic biomaterials have been used as alternatives to bone grafting. Synthetic biomaterials such as beta tricalcium phosphate (β-TCP) are biocompatible, biodegradable, and osteoconductive, guiding osteoblastic cells and promoting bone formation. Thus, the objective was to evaluate the influence of chronic ethanol intake on the bone healing process of cranial defects treated with β-TCP® compared to those filled with blood clot. Forty male rats were used (Rattusnorvegicus), randomly divided into two groups: GAG received water as a liquid diet, and GAL received 25% ethanol. The GAL group was initially subjected to gradual adaptation to the alcohol and then maintained at 25% for 90 days. At the end of this period, all animals were submitted to experimental surgery. In the parietal bone of each animal, two cavities were prepared, 5.0 mm in diameter on the side of the sagittal suture, and the right parietal was filled with β-TCP® and left to clot. Thus, the GAG and GAL groups were divided according to the filling of defects: GC-AG (Clot Water Group); GC-AL (Clot Alcohol Group); GB-AG (Biomaterial Water Group); and GB-AL (biomaterial Alcohol Group). The bone repair was observed according to the euthanasia period: 10; 20; 40; and 60 days after surgery. After a histological inclusion, the pieces were submitted to histomorphological and histomorphometric analysis. The histomorphological analysis was observed in the initial periods of all groups’ fibrous connective tissue filling the entire central area of the defect. The groups of defects filled with β-TCP showed tissue reaction to particles surrounded by inflammatory cells. At the end of the period of analysis, it was observed that in all groups there was little bone formation, with...

Avaliação microtomográfica e histomorfométrica comparativa de levantamento de seio maxilar em coelhos utilizando diferentes cerâmicas a base de fosfato de cálcio / Comparative microtomographic and histomorphometric evaluation of maxillary sinus augmentation using different calcium phosphate-based ceramics

A técnica de levantamento de seio maxilar (LSM) visa aumentar a altura óssea junto à superfície sinusal de maxila posterior atrófica utilizando diferentes materiais de preenchimento, para possibilitar a instalação de implantes dentários. Esses materiais de preenchimento podem variar quanto à origem e às propriedades físicoquímicas, resultando em diferentes respostas biológicas. O objetivo do atual trabalho foi avaliar a eficiência do Gen-Ox®inorg e GenPhos XP® na técnica de elevação do seio maxilar em comparação ao Bio-Oss®. Em 24 coelhos foi realizado o levantamento bilateral dos seios maxilares (SMs) utilizando 200 mm3 de material de preenchimento por seio, conforme os grupos experimentais Bio-Oss (6SMs/período), Gen-Ox (5SMs/período) e GenPhos (5SMs/período), e a janela óssea de acesso foi recoberta com uma membrana reabsorvível. Os animais de cada grupo foram eutanasiados aos 15, 30 e 60 dias e a região dos SMs foi coletada e fixada em formalina a 10% tamponada. As peças foram submetidas à análise microtomográfica para determinação do volume total do SM elevado e em seguida ao processamento histológico, sendo cortes coronais dos SMs obtidos e avaliados morfometricamente pelo método de volumetria de pontos. Todos os três materiais apresentaram excelente biocompatibilidade e promoveram a manutenção do volume do seio preenchido ao longo do tempo, sendo em média de 214,1 mm3. Em todos os grupos a formação óssea ocorreu em íntimo contato com as partículas de material. Ao término de 60 dias, o tecido ósseo formado mostrava-se maduro e preenchia parcialmente os espaços entre as partículas. A forma e tamanho das partículas de Gen-Ox gerou maior espaço entre as partículas que pode ter levado a formação de maior volume de tecido ósseo e de tecido conjuntivo (53,0 ± 10,1 mm3 e 74,1 ± 21,5 mm3) comparado ao Bio-Oss (43,7 ± 11,6 mm3 e 61,2 ± 23,3 mm3) e GenPhos (47,5 ± 10,4 mm3 e 58,5 ± 25,7 mm3). Baseado na estabilidade do volume sinusal elevado, na capacidade osteocondutora e na formação e maturidade óssea ao longo do tempo promovidos pelo Gen-Ox®inorg e GenPhos®, comparável ao do Bio-Oss®, conclui-se que esses dois biomateriais significam uma alternativa segura na técnica de LSM.(AU)

Maxillary sinus augmentation (MSA) for implant placement using bone graft or bone substitutes is a common procedure to increase the bone volume in the atrophic posterior part of the maxilla. Various bone substitutes have been used in sinus floor elevation procedures. Nonetheless, the biological performance of bone substitutes may vary according to origin, physical and chemical properties. The goal of this study was to evaluate the efficiency of both Gen-Ox®inorg and GenPhos XP® in maxillary sinus augmentation technique compared to Bio-Oss®. In 24 rabbits, it was conducted a bilateral lifting of the maxillary sinuses (MSs) using 200 mm3 of filling material for sinus in accordance with the experimental groups Bio-Oss (6SMs/period), Gen-Ox (5MSs/period) and GenPhos (5MSs/period). The sinus access window was covered with a resorbable membrane. The animals of each group were euthanized at 15, 30 and 60 days and the MSs were collected and fixed in 10% buffered formalin. The samples were submitted to microtomographic analysis to calculate the MS augmentation volume. Histological coronal sections of MS augmentation were used for morphological analysis and determination of volume density of each structure by point counting volumetry method. All three materials had excellent biocompatibility and promoted maintenance of the MS augmentation volume over time, averaging 214.1 mm3. In all groups the bone formation occurred in close contact with the material particles. At the end of 60 days, the bone tissue formed was mature and it partially filled the spaces between the particles. The shape and size of Gen-Ox particles generated greater space between the particles that may have led to a higher formation of bone volume and connective tissue (53.0 ± 10.1 mm3 and 74.1 ± 21.5 mm3) than Bio-Oss (43.7 ± 11.6 mm3 and 61.2 ± 23.3 mm3) and GenPhos (47.5 ± 10.4 mm3 and 58.5 ± 25.7 mm3). Based on the stability of the MS volume, the osteoconductive capacity and the bone formation and maturation over time promoted by Gen-Ox®inorg and GenPhos®, and comparable to Bio-Oss®, it is concluded that these two biomaterials may be a safe alternative in MSA technique.(AU)

Use of autogenous bone and beta-tricalcium phosphate in maxillary sinus lifting: a prospective, randomized, volumetric computed tomography study.

The correction of bone defects can be performed using autogenous or alloplastic materials, such as beta-tricalcium phosphate (ß-TCP). This study compared the changes in bone volume (CBV) after maxillary sinus lifting using autogenous bone (n = 12), autogenous bone associated with ß-TCP 1:1 (ChronOS; DePuy Synthes, Paoli, CA, USA) (n = 9), and ß-TCP alone (n = 11) as grafting material, by means of cone beam computed tomography (CBCT). CBV was evaluated by comparing CBCT scans obtained in the immediate postoperative period (5-7 days) and at 6 months postoperative in each group using OsiriX software (OsiriX Foundation, Geneva, Switzerland). The results showed an average resorption of 45.7 ± 18.6% for the autogenous bone group, 43.8 ± 18.4% for the autogenous bone+ß-TCP group, and 38.3 ± 16.6% for the ß-TCP group. All bone substitute materials tested in this study presented satisfactory results for maxillary sinus lifting procedures regarding the maintenance of graft volume during the healing phase before the insertion of implants, as assessed by means of CBCT.

Use of rhBMP-2/ß-TCP for Interpositional Vertical Grafting Augmentation: 5.5-Year Follow-up Clinically and Histologically.

PURPOSE: This case report documented long-term results using rh-BMP-2/ß-tricalcium phosphate (TCP) for vertical grafting augmentation. MATERIALS AND METHODS: A 58-year-old patient with extreme atrophy of the left posterior mandible was treated with rh-BMP-2/ß-TCP for vertical bone augmentation. At the time of implant placement, bone biopsy was performed for histological evaluation. RESULTS: Seven months after surgery, CT scan demonstrated approximately 8 mm of bone gain height. The histological results revealed a newly formed vital bone tissue, predominantly lamellar with variable density. Remaining bone ceramic surrounded by newly formed bone tissue or connective tissue was observed. The bone levels remained unchanged during the entire period treatment (5.5 years). CONCLUSION: This technique has demonstrated a potential for reconstruction of atrophic sites when vertical bone gain is desirable. Moreover, the bone gain has shown long-term maintenance without resorption. Future long-term prospective clinical trials are needed to confirm these findings.

Impact of human maxillary sinus volume on grafts dimensional changes used in maxillary sinus augmentation: a multislice tomographic study.

PURPOSE: To assess the influence of complete maxillary sinus volume on the dimensional changes of different grafts used in maxillary sinus lift. MATERIALS AND METHODS: Analysis of 50 surgical procedures of maxillary sinus lift performed on 43 subjects using different grafting materials: fresh frozen allogenic particulated bone (11), hydroxyapatite (Endobon(®)) (17), 60% hydroxyapatite + 40% beta-tricalcium phosphate (Bone Ceramic(®)) (12) and Bone Ceramic(®) + Emdogain(®) (10). One hundred and fifty multislice tomographic images of the maxillary sinus were obtained using the software Syngo CT 2011 A VOLUME, measuring complete maxillary sinus volume (T0) and dimensional changes of different graft materials during periods of 15 days (T1) and 180 days (T2). The factor studied was the influence of maxillary sinus volume on the dimensional changes of different graft materials used in maxillary sinus lift in patients with posterior edentulism. Data obtained were assessed using the Student's t-test and Pearson's correlation coefficient. RESULTS: No correlation (r 0.112) between the total maxillary sinus volume and the dimensional changes of the different graft materials used in this study was observed (P > 0.05). CONCLUSION: This study demonstrated that there is no sufficient evidence to support the thesis that the volume of the maxillary sinus influences the contraction of the grafts, at least on sample or the biomaterials evaluated in this cohort study.

Clinical, radiographic, and histological analyses of calcium phosphate cement as filling material in maxillary sinus lift surgery.

BACKGROUND: The installation of dental implants in the posterior maxilla is often faced with resorbed alveolar processes, resulting from a combination of pneumatization of the maxillary sinus, the effects of periodontal disease, and physiological bone resorption. The sinus lift surgery has been practiced since 1980 with the aim to increase bone height in this region for an implant supported prosthetic rehabilitation, and various filling materials have been used for such. OBJECTIVES: This study aimed to clinically, radiographically, and histologically evaluate a preparation of calcium phosphate cement (Bone Source(®), BS) used as filling material in maxillary sinus elevation surgery. METHODS: Ten patients were operated requiring maxillary sinus graft for future placement of osseointegrated implants. After a period ranging from 9 to 16 months, a clinical evaluation and biopsy of the grafted area in the region adjacent to the axis of the implant to be inserted were performed. RESULTS: Clinically and radiographically, no evidence of resorption/substitution of BS was noticed. Although no patients have had postoperative complications and the material presented fully biocompatible characteristics with woven bone in intimate contact with BS, it was not possible to place any implants due to minimal bone formation and friability of the material. CONCLUSION: It was concluded that despite the osteoconductive capacity of BS, this conventional calcium phosphate preparation does not support sufficient amount of new bone formation that could allow its use as filling material for maxillary sinus floor lift and subsequent dental implant placement.