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Objective Using a mouse osteoporotic model, this study aimed to determine the influence of hydrophilic titanium surfaces on gene expression and bone formation during the osseointegration process. Background Based on the previous evidence, it is plausible to assume that osteoporotic bone has a different potential of bone healing. Therefore, implant surface modification study that aims at enhancing bone formation to further improve short- and long-term clinical outcomes in osteoporosis is necessary. Material and methods Fifty female, 3-month-old mice were included in this study. Osteoporosis was induced by ovariectomy (OVX, test group) in 25 mice. The further 25 mice had ovaries exposed but not removed (SHAM, control group). Seven weeks following the ovariectomy procedures, one customized implant (0.7 × 8 mm) of each surface was placed in each femur for both groups. Implants had either a hydrophobic surface (SAE) or a hydrophilic treatment surface (SAE-HD). Calcium (Ca) and phosphorus (P) content was measured by energy-dispersive X-ray spectroscopy (EDS) after 7 days. The femurs were analyzed for bone-to-implant contact (BIC) and bone volume fraction (BV) by nano-computed tomography (nano-CT) after 14 and 28 days. Same specimens were further submitted to histological analysis. Additionally, after 3 and 7 days, implants were removed and cells were collected around the implant to access gene expression profile of key osteogenic (Runx2, Alp, Sp7, Bsp, Sost, Ocn) and inflammatory genes (IL-1β, IL-10, Tnf-α, and Nos2) by qRT-PCR assay. Statistical analysis was performed by ANOVA and paired t test with significance at P Results The amount of Ca and P deposited on the surface due to the mineralization process was higher for SAE-HD compared to SAE on the intra-group analysis. Nano-CT and histology revealed more BV and BIC for SAE-HD in SHAM and OVX groups compared to SAE. Analysis in OVX group showed that most genes (ie, ALP, Runx2) involved in the bone morphogenetic protein (BMP) signaling were significantly activated in the hydrophilic treatment. Conclusion Both surfaces were able to modulate bone responses toward osteoblast differentiation. SAE-HD presented a faster response in terms of bone formation and osteogenic gene expression compared to SAE. Hydrophilic surface in situations of osteoporosis seems to provide additional benefits in the early stages of osseointegration.

Purpose To evaluate whether a hydrophilic surface treatment compared with a hydrophobic implant surface can enhance osseointegration by analysis of calcium deposition, bone-to-implant contact (BIC), bone volume (BV), and upregulation of genes involved in bone formation. Materials and methods Sixty implants (n = 60) with a hydrophobic (SAE) or hydrophilic (SAE-HD) surface treatment were placed bilaterally in each femur of 3-month-old male mice (n = 30). Scanning electron microscopy (SEM) and energy-dispersive x-ray spectroscopy (EDS) were utilized for quantifying the presence of calcium on the implant surface 7 days after implant placement. The specimens were analyzed after 14 and 21 days for BIC and BV by Nano CT scanning followed by histologic evaluation. Additionally, 1, 3, and 7 days postsurgery, femurs were harvested, implants were explanted, and gene expression (Sp7, Bsp, Sost, IL-1α, and IL-10) by quantitative real-time polymerase chain reaction was studied. Moreover, implants were characterized for surface roughness area. Data were statistically analyzed with two-way analysis of variance (ANOVA) followed by the Tukey test (P Results The amount of calcium on the surface was higher for SAE-HD after 7 days. Nano CT revealed significantly more BV in the SAE-HD than the SAE surface. The histologic assessment showed increased BIC in SAE-HD in comparison to SAE. SAEHD showed significantly increased levels of genes involved in bone formation. Conclusion Both surfaces were able to modulate bone responses toward osteoblast differentiation. SAE-HD presented a better response compared with SAE.

The aim of this clinical report is to present the replacement of unsatisfactory metal-ceramic crowns of elements 12, 11, 21 and 22, by lithium disilicate glass-reinforced ceramic crowns in a patient with skeletal anterior open bite. A patient sought care at the Dental Hospital at the School of Dentistry of UFU, complaining of odor between the metal-ceramic crowns of the antero-superior teeth. After clinical and radiographic examination, invasion of the biological space was noticed, surgery was indicated in order to restore the biological space. After healing, the pre-existing cast metal posts were masked using an opaque composite resin and the teeth were reprepared for full all-ceramic crowns. Impressions were taken in two steps, using PVS associated to retraction cords. The ceramic copings were obtained in lithium disilicate ceramic, and the veneering was performed by stratification. After testing the ceramics crowns in relation to, fit, function and aesthetic results, cementation was completed using modified absolute isolation, followed by prophylaxis of preparations with pumice and saline, surface treatment of the ceramic restorations and luting using self-adhesive resin cement. Finally, an occlusal splint was produced to control the effects of bruxism and orofacial pain symptoms. The anterior open skeletal bite was a challenging factor for the rehabilitation of this patient; however, one must consider the entire process that the patient would undergo if choosing for orthognathic surgery, and the patient should be aware of the case limitations. In addition, the use of lithium disilicate glass-reinforced ceramics proved the versatility of this material for anterior aesthetic restorations. El objetivo de este caso clínico es demonstrar la sustitución de coronas metal-cerámicas insatisfactorias de los elementos 12, 11, 21 y 22, por coronas cerámicas reforzadas con disilicato de litio en paciente con mordida abierta esquelética anterior. Paciente acudió al Hospital Odontológico de la Facultad de Odontología de la UFU quejándose de mal olor entre las coronas instaladas en dientes anteriores. Tras examen clínico y radiográfico, fue conprobado invasión del espacio biológico y la necesidad de una cirugía de aumento de corona clínica. Después de la curación, los núcleos metálicos preexistentes fueran enmascarados con resina compuesta opaco y repreparados. Fue empezado el moldeo en dos pasos, utilizando silicone por adicion y fios retractores. Los copings fueram hecho en disilicato de lítio y fueran recobiertas por cerámica por la tecnica de estratificacion. Después de probar la cerámica para la adaptación, función y resultados estéticos, se realizó la cementación con aislamiento absoluto modificado, seguido de profilaxis con piedra pómez y solución salina, tratamiento superficial interno de la piezas cerámicas y la cementación con cemento resinoso autoadesivo. Finalmente, se colocó una placa estabilizadora oclusal para controlar los efectos del bruxismo y su dolor orofacial. La mordida esquelética abierta fue un reto em esto caso clínico, sin embargo, se debe tener en cuenta todo el proceso que atravesaría si se optara por la cirugía ortognática, y lo paciente se debe tener en cuenta las limitaciones del caso. Además, el uso de cerámicas reforzadas con disilicato de litio demuestra su versatilidad para restauraciones anteriores. O objetivo deste relato de caso foi demonstrar a substituição de coroas metalocerâmicas insatisfatórias nos elementos 12, 11, 21 e 22, por coroas cerâmicas reforçadas por dissilicato de lítio em paciente com mordida aberta esquelética anterior. Paciente procurou atendimento no Hospital Odontológico da Faculdade de Odontologia da UFU se queixando de odor entre as coroas instaladas nos dentes anteriores. Após exame clínico e radiográfico foi constatado invasão de espaço biológico e a necessidade de cirurgia de aumento de coroa clínica. Após cicatrização, os núcleos metálicos pré-existentes foram mascarados com resina composta opaca e repreparados. Foi realizado moldagem de trabalho em dois passos, utilizando silicone por adição associado a fios afastadores. Os copings cerâmicos foram confeccionados em dissilicato de lítio e cerâmica de cobertura foi aplicada pela técnica de estratificação. Após realizar a prova das cerâmicas em relação a adaptação, função e estética, a cimentação das coroas foi realizada utilizando isolamento absoluto modificado, seguido de profilaxia com pedra pomes e soro fisiológico, tratamento da superfície interna das peças cerâmicas e cimentação empregando cimento resinoso autoadesivo. Por último, foi confeccionada placa oclusal estabilizadora para controle dos efeitos do bruxismo e da dor orofacial. A mordida aberta esquelética foi um desafio para a substituição das restaurações indiretas nesse caso, porém, deve-se levar em consideração todos os procedimentos necessários caso a paciente optasse pela cirurgia ortognática, devendo a mesma estar ciente das limitações do caso. Além disso, a utilização de cerâmicas reforçadas por dissilicato de lítio comprova a sua versatilidade para restaurações estéticas anteriores.

Periodontal treatment for teeth with a furcation lesion is a challenge for the dental surgeon due to the remaining tissue complexity, limiting the prognosis of the therapy. The assumption of this study is that auxiliary therapy with regenerative approaches could increase the chances of clinical success. Thus, the objective was to evaluate the effect of the combination of Scraping and Root Straightening (RAR) and Fibrin Rich Plasma (PRF) in the treatment of grade II furcation injury. The systematic review was carried out following the PRISMA criteria, including the PICO strategy for the study design. The PubMed, Scopus, Cochrane DataBase, SciELO, LILACS databases were used. The search strategy included the terms MeSH and DeCS and was carried out in September 2019. With this research, it was observed that the studies available in the literature do not present a standardization in the study of PRF for treatments of grade II furcation injuries. Therefore, in this review, we cannot state that PRF is the gold standard for treating furcation injuries, although statistically it presents more satisfactory results. We emphasize the importance of further studies associating RAR and PRF in a more judicious manner and with more methodologies of investigation such as histological, morphological and image analyzes in studies to assess the validation of tissue neoformation in the treatment of grade II furcation injury.

Surface treatment alone does not determine the final microtopography of a dental implant, which can be influenced by implant design and the surgical procedure. This study investigated the effect of surgical placement of dental implants with same surface treatments on surface roughness. Three implants (SIN) of each group with different macrogeometries (Strong, Stylus, and Tryon) were analyzed using laser interferometry and scanning electron microscopy to evaluate surface topography. All threaded regions of the implants, namely, top, flank, and valley, were analyzed individually. Relevant surface parameters (Sa, Ssk, Sku, Str, and Sdq) were calculated for the different regions on each implant before (B) (n = 9) and after (A) (n = 9) placement into porcine rib bones. The behavior and proliferation of a preosteoblastic cell line MC3T3-E1 on titanium surface, cell viability, and osteopontin secretion were evaluated after 24 h, 48 h, and 96 h, also before (n = 18) and after (n = 18) implant placement into porcine ribs bone. As results, the valleys of all implants had an increase in Sa values after implant placement. By contrast, the tops of the Stylus A implant and the flanks of the Tryon A implant showed a significant decrease in mean height of the irregularities (Sa), 0.16 µm and 1.25 µm, respectively. The Stylus implant presented significantly (p<0.05) higher asymmetry values on the distribution curve for irregularity heights (Sku) in all regions after insertion into bone (6.99 for tops, 9.54 for flanks, and 17.64 for valleys), indicating a greater preponderance of peaks over valleys. An increase in roughness gradients (Sdq) was observed for all macrogeometries after insertion into bone. The cell culture results showed no significant difference (p>0.05) for all macrogeometries after bone placement. In conclusion, a subtle change in implant surface roughness was detected after insertion into bone for all the macrogeometries, without significantly affecting the cellular parameters studied.

Commercial cellulose diacetate (DS = 2.45) was partially deacetylated to an appropriate degree of substitution and, after being embedded with tetracycline, was evaluated both as a device for controlled drug release and as an absorbable (degradable) barrier for use as an adjuvant in periodontal reconstitution. The kinetics of both processes were studied in vitro, showing that the process of release fit perfectly to a pseudo-second order model, with rapid desorption in the first 8 h, then slow release for up to 96 h. The estimated degradation time of the membrane was 99 days. Both results indicate the potential of using this membrane as a degradable drug release device.

The purpose of this study was to evaluate the effect of roughness parameters and hydrophobicity of restorative material used to restore non-carious cervical lesions on the biofilm formation. Four restorative materials were investigated: conventional glass ionomer cement (KF, Ketac Fill Plus, 3M ESPE), resin-modified glass ionomer cement (VT, Vitremer, 3M ESPE), nanofilled resin-modified glass ionomer cement (KN, Ketac Nano, 3M ESPE), and nanofilled resin composite (FZ, Filtek Z350 XT, 3M ESPE). Forty disk specimens were prepared from each material, dived in four groups. Five samples were used for topography parameters analysis using a 3D profilometry. The amplitude parameters (Sa and Sq), spatial parameter (Sds), and hybrid parameter (Ssc) were extracted in area using cut-off of 0.25 mm. Hydrophobicity was determined by the contact angle measurement of deionized water on the surface. The biofilm collected from a 24-year-old subject was grown on modified brain–heart infusion agar under aerobic conditions at 37 °C for 24 h. Each test disk was immersed in 200 µL of biofilm suspension (n = 10) and incubated for 24 h at 37 °C. Biofilm was evaluated after 24 h formation on each disk after stained with 1 % fluorescein using confocal laser-scanning microscopy. Data were analyzed using one-way ANOVA and Tukey test (α = 0.05), Pearson correlation was used to compare topography parameters with biofilm formation. Significant differences were found in related amplitude parameters (Sa and Sq, FZ = KN > VT > KF). KN presented the highest hydrophobicity. FZ and KN presented the lowest thickness and biovolume of biofilm when compared with VT and KF. All topography parameters were significantly correlated with biofilm formation. FZ and KN, material with nanoparticles presented better performance-related topography parameters and biofilm formation. Clinical relevance: The incorporation of nanotechnology into restorative materials promotes better surface topography with lower biofilm formation.

The aim of this study was to evaluated the root surfaces modifications resulted by application of different chemicals agents, and their influence on the fibrin network and fibroblasts attachment. From 96 anterior mandibular human extracted incisor teeth, 192 dentin blocks of buccal and lingual surface were obtained and randomly divided into 6 groups: Cont- control group, which received no treatment; Root surface scaling and root planing (Srp); Citric acid-Srp; EDTA-Srp; Tetracycline capsule-Srp; Tetracycline gel-Srp. After dentin treatments the specimens were analyzed as follows: 1) demineralization level and residues of the product by scanning electron microscopy (SEM); 2) adhesion of blood components after 20 min of surface treatment by SEM; 3) fibroblast attachment after 24 h by SEM; 4) cell metabolism after 24 h by MTT assay. Data were analyzed using Fisher Exact, One-way ANOVA test followed by Dunn's test, Tukey test and Dunnett test (α=0.05). Citric acid, EDTA and Tetracycline gel resulted in adequate demineralization with no completely smear layer and smear plug removal on root dentin surface. Tetracycline capsule produced great tetracycline residues with several demineralization areas. Tetracycline gel and EDTA groups presented more fibroblast fixation than other experimental groups. The highest mean blood clot adhesion score was observed in roots treated with tetracycline gel. EDTA and Tetracycline gel surface treatment removed the smear layer over dentin surface and promoted adhesion of fibrin network and fibroblast cells attachment. Resumo O objetivo deste estudo foi avaliar modificações nas superfícies radiculares sofridas pela aplicação de diferentes agentes químicos, e sua influência sobre a rede de fibrina e adesão de fibroblastos. A partir de 96 incisivos inferiores humanos, 192 blocos de dentina das superfícies vestibular e lingual foram obtidos e divididos aleatoriamente em 6 grupos: Cont-grupo controle, não recebeu nenhum tratamento; Raspagem e alisamento radicular (RAR); Ácido cítrico-SRP; EDTA-SRP; Tetraciclina em cápsula-SRP; Tetraciclina gel-SRP. Após o tratamento da dentina as espécimes foram analisadas: 1, nível de desmineralização e resíduos do produto por microscopia eletrônica de varredura (MEV); 2, adesão dos componentes sanguineos após 20 min na tratamento de superfície por SEM; 3, adesão de fibroblastos após 24h por SEM; 4, o metabolismo celular após 24 h por ensaio MTT. Os dados foram analisados por Fisher Exact, teste one-way ANOVA, seguido pelo teste de Dunn, teste de Tukey e teste de Dunnett (α = 0,05). O ácido cítrico, EDTA e gel tetraciclina resultaram na adequada desmineralização sem remoção completa de camada de smear layer e smear plug sobre a superfície da dentina radicular. Cápsula de tetraciclina produziu grandes resíduos de tetraciclina com várias áreas de desmineralização. Os grupos Gel de tetraciclina e EDTA apresentaram maior adesão de fibroblastos do que os demais grupos experimentais. O maior score de adesão de coágulo sanguineo foi observado nas superfícies tratadas com gel de tetraciclina. EDTA e Gel de tetraciclina removeram a camada de smear layer sobre a superfície da dentina e promoveu adesão da rede de fibrina e de fibroblastos.

Background To analyze articles that studied patients submitted to diphosphonates therapy and who received dental implants before, during or after bisphosphonate (BP) treatment, compared to healthy patients, analyzing the increase of failure and loss of implants or bisphosphonate related osteonecrosis of the jaw (BRONJ) incidence. Material and Methods The Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) statement was used in this study. The clinical question in “PICO” format was: In patients under bisphosphonate therapy, do dental implants placement, compared to healthy patients, increase the failure and loss of implants or bisphosphonate related osteonecrosis of the jaw incidence? PubMed/MEDLINE was searched for articles published up until April 15, 2015 using a combination of MeSH terms and their Entry terms. Results The search resulted in 375 articles. After selection according to the eligibility criteria, 15 studies fulfilled were included (eight retrospective, one prospective and six case series), with a total of 1339 patients analyzed, 3748 implants placed, 152 loss of implants and 78 cases of BRONJ. Conclusions Due to the lack of randomized clinical trials looking at this theme, further studies with longer follow-up are needed to elucidate the remaining questions. Thus, it is wise to be careful when planning dental implant surgery in patients undergoing bisphosphonate therapy because of the risk of developing BRONJ as well as occurring failure of implant. Moreover, complete systemic condition of the patient must be also taking into considering when such procedures are performed. Key words:Bisphosphonates, diphosphonates, dental implants, osteonecrosis.

Objectives The influence of bone loss and periodontal splinting on strains in supporting bone is still not well understood. The aim of this study was to analyse the effect of bone loss and periodontal splints on strains in an anterior mandible structure. Methods Ten anterior mandible models were fabricated using polystyrene resin. Eighty human teeth were divided in 10 groups (right first premolar to left premolar) and embedded in simulated periodontal ligament. Strain gauges were attached to the buccal and lingual mandible surfaces. The models were sequentially tested for 7 conditions: no bone alterations and no splinting; 5 mm of bone loss between canine teeth; bone loss associated with resin splint between canine teeth; bone loss with wire splint; bone loss with wire/resin splint; bone loss with extracoronal fibre–glass/resin splint; and bone loss with intracoronal fibre–glass/resin splint. Oblique loads (50, 100, and 150 N) were applied on the teeth. Data were analysed using 3-way ANOVA and Scheffe's test ( α = .05). Results Strains on buccal surface were higher than on lingual surface. Bone loss resulted in strain increase at 100 and 150 N loading. Dental splinting with resin resulted in strain values similar to the control levels. Conclusions Bone loss increased strain mainly in the buccal region. Dental splints with adhesive system and composite resin produced lower bone strains irrespective of occlusal load.

Purpose: The degree of stress generated in the endodontically treated and restored tooth can be influenced by the composition and configuration of the dowels used for the restoration. Using two-dimensional (2D) finite element analysis (FEA), this study tested the hypothesis that the characterization of the stress distribution can be influenced by which evaluation method is employed: protrusion loading and 4-point flexural strength test or varying the type of material (carbon and glass fiber) or the external configuration of the dowel (smooth and serrated). Materials and Methods: For simulation of the protrusion load test, models were generated with Mechanical-AutoCAD V6 software from an image of an anatomical plate, one maxillary central incisor, and two dowels and exported to Ansys 9.0. The bone region model was fixed, and a tangential load of 1 N with a 135° inclination to the tooth longitudinal axis was applied at the level of the palatal surface of the crown. In the simulation of a 4-point flexural strength test, a 1 N perpendicular load was applied in two points to the dowel. The dental materials and structures were considered elastic, isotropic, homogeneous, and linear, with the exception of the dowel, which was assumed to exhibit orthotropic behavior. Mechanical properties were defined based on a review of the literature, and the model was meshed with an eight node tetrahedral element. Results: The stress results from both tests were analyzed according to von Mises criteria and principal stresses (Sx). Data from the 4-point flexural strength test simulation showed that, for the serrated dowels, a higher stress concentration was found; however, no difference in the occlusal load for material or dowel configuration was found. Conclusions: These results suggest that although the external configuration of the dowel influences direct loading, when the dowel is integrated to the tooth and setting material, the influence on biomechanical behavior disappears.

In order to complement non-surgical therapy in periodontitis, there are multiple options of antimicrobials, such as metronidazole, chlorhexidine, minocycline, doxycycline and tetracycline, which can be locally delivered into the mucosa. These drugs are used in periodontal pockets and can inhibit or eliminate periodontopathogenic microorganisms as well as modulate the inflammatory response of tissues. However, limited data are available concerning the relationship between effect, efficacy and clinical status of the periodontium. This review aims to evaluate the effect and the efficacy of five types of local drug delivery systems in clinical parameters of periodontology. Researched papers using MEDLINE via PubMed, and LILACS databases related to five types of local drug delivery systems as chlorhexidine gluconate, doxycycline hyclate, metronidazole gel, minocycline ointment and tetracycline fibers, were reviewed aiming to address the mechanism of action and the evidence of clinical effectiveness of adjunctive use of these antimicrobials following surgical and/or non-surgical therapies. Inclusion criteria defined that articles must be randomized controlled trials performed in humans and published between 1996 and 2014. The adjunctive use of local drug delivery systems with controlled release properties may provide a defined, but limited, beneficial response on periodontal pockets. Furthermore, local drug delivery as an active treatment or maintenance therapy depends on clinical findings, responses to treatment described in the literature, desired clinical outcomes, and patients' dental and medical histories, including their past usage of antimicrobials.

Purpose: Because the microtopography of titanium implants influences the biomaterial-tissue interaction, surface microtexturing treatments are frequently used for dental implants. However, surface treatment alone may not determine the final microtopography of a dental implant, which can also be influenced by the implant macrogeometry. This work analyzed the effects on surface roughness parameters of the same treatment applied by the same manufacturer to implants with differing macro-designs. Materials and Methods: Three groups of titanium implants with different macro-designs were investigated using laser interferometry and scanning electron microscopy. Relevant surface roughness parameters were calculated for different regions of each implant. Two flat disks (treated and untreated) were also investigated for comparison. Results: The tops of the threads and the nonthreaded regions of all implants had very similar roughness parameters, independent of the geometry of the implant, which were also very similar to those of flat disks treated with the same process. In contrast, the flanks and valleys of the threads presented larger irregularities (Sa) with higher slopes (Sdq) and larger developed surface areas (Sdr) on all implants, particularly for implants with threads with smaller heights. The flanks and valleys displayed stronger textures (Str), particularly on the implants with threads with larger internal angles. Conclusion: Parameters associated with the height of the irregularities (Sa), the slope of the asperities (Sdq), the presence of a surface texture (Str), and the developed surface area of the irregularities (Sdr) were significantly affected by the macrogeometry of the implants. Flat disks subjected to the same surface treatment as dental implants reproduced only the surface topography of the flat regions of the implants.

Failures may occur in the connections of dental implants, especially in external hexagon (EH). Due to the deformations in this portion of implants, this study aimed to evaluate the levels of deformation of EH connections subjected to internal toque. Two types of implants were used: N group and S group. Torques of 0, 32, 45, 60 and 80 Ncm were applied to the N group, and torques of 0, 30, 40, 60 and infinite Ncm were applied to the S group implants. The internal distance (ID), internal area (IA) and external area (EA) of the EH were obtained from digital pictures, which were analyzed by a specific software. Statistical analysis was performed by the Scott-Knott test. The results showed that the higher the torque applied, the greater were the changes in the evaluated dimensions in both groups. In the S group, torque levels equal or greater than 40 Ncm and 30 Ncm caused greater deformation of EA and IA respectively, while in the N group, torque levels equal or greater than 60 Ncm and 32 Ncm caused greater deformation of EA and IA respectively. Levels of deformation were greater in the S group as compared with the N group. These findings suggest that the IA, EA and ID of the EH may be affected by different internal torque levels. Falhas podem ocorrer em conexões de implantes dentários, em especial em hexágonos externos (EH). Devido à ocorrência de deformação nesta porção dos implantes, este estudo objetivou avaliar os níveis de deformação de conexões EH submetidas ao torque interno. Dois tipos de implantes foram utilizados: grupo N e grupo S. Foram aplicados torques de 0, 32, 45, 60 e 80 Ncm nos implantes do grupo N e torques de 0, 30, 40, 60 Ncm e infinito nos implantes do grupo S. Medidas referentes à distância interna (ID), área interna (AI) e área externa (AE) foram obtidas por meio de fotos digitais analisadas em software. A análise estatística foi feita pelo teste de Scott-Knott. Os resultados demonstraram que quanto maior o torque aplicado, maior a alteração de todas as dimensões avaliadas em ambos os grupos. No grupo S, torques iguais ou superiores a 40 Ncm e 30 Ncm causaram maior deformação na AE e AI respectivamente, enquanto no grupo N, torques iguais ou superiores a 60 Ncm e 32 Ncm causaram maior deformação na AE e AI respectivamente. Os níveis de deformação foram maiores no grupo S em comparação ao grupo N. Nossos resultados indicam que a AI, a AE e a DI do EH podem ser influenciadas pelos diferentes torques internos.

The aim of this study was to analyze the effect of the separation of prosthetic crowns from fixed partial dentures by means of stress gradient evaluation. Three photoelastic models were created to examine contiguous implants with varying contact between the crowns (contact point [CP], contact surface [CS], splinted [SP]). The SP group presented the best results, followed by the CS group, indicating that the use of splinted prosthetic crowns and crowns with broad surface contacts is viable when considering the stress values.

The dental pulp may be exposed to several irritants that are potentially noxious to the health and functions of this tissue. Each type of irritant or injury has different effects on the pulp, which are generally characterized by acute inflammation, chronic inflammation or necrosis. Common examples of irritants are dental caries, cavity preparation procedures, traumatic injuries, and chemical substances like bleaching agents and adhesive systems. The present study aimed to review the current knowledge about the effect of bleaching agents and adhesive systems in the human dental pulp. The review covered literature from 2004 to 2009, and only relevant manuscripts were included. Hand search of the references completed the review. Based on literature review, it may be concluded that all dental procedures associated with bleaching agents or adhesive systems involve risks to cause pulp damage. However, these risks can be minimized if the causal factors were known and avoided.

This study compared the cytotoxicity and the release of nitric oxide induced by collagen membranes in human mononuclear cells. Peripheral blood was collected from each patient and the separation of mononuclear cells was performed by Ficoll. Then, 2x10(5) cells were plated in 48-well culture plates under the membranes in triplicate. The polystyrene surface was used as negative control. Cell viability was assessed by measuring mitochondrial activity (MTT) at 4, 12 and 24 h, with dosage levels of nitrite by the Griess method for the same periods. Data had non-normal distribution and were analyzed by the Kruskal-Wallis test (p

RESUMOEste trabalho avaliou a resistência adesiva (μTBS) na fixação de restaurações indiretas por meio de cimento resinoso e adesivo auto-condicionante sob influência de diferentes tratamentos prévios de esmalte e dentina. Trinta incisivos bovinos foram extraídos e tiveram suas raízes cortadas na junção cemento-esmalte. A superfície vestibular dos dentes foi lixada até exposição de dentina superficial, padronizando a formação de smear layer. As amostras foram divididas aleatoriamente em três grupos (n=10): G1: aplicação do adesivo auto-condicionante One up Bond F (OB), seguindo as instruções do fabricante; G2:condicionamento com ácido fosfórico à 37% em esmalte e dentina seguindo aplicação de (OB); G3: jateamento com óxido de alumínio 50μm em esmalte e dentina previamente à aplicação de (OB). Restaurações indiretas com resina composta foram fixadas usando cimento resinoso dual e as amostras foram cortadas com área adesiva de aproximadamente 1,0 mm² em três regiões: esmalte (E), dentina periférica (DP) e dentina central (DC). Foram submetidas a ensaio de microtração em máquina de ensaio mecânico em velocidade de 0,5mm/min. Após fratura, as amostras foram analisadas em Microscopia Eletrônica de Varredura (MEV) para avaliação do padrão de fratura. Os valores de (μTBS) foram expressos em MPa e os dados foram analisados em ANOVA seguido por teste Tukey (p

Osseointegrated dental implants are inserted into the alveolar ridge, and for them to function as tooth replacements, the surrounding tissues need to adapt to them. Just as with teeth, dental implants traverse the oral mucosa and have access to the contaminated environment of the oral cavity. Therefore, periodontal and peri-implant tissues are important for establishing a protective barrier. The aim of the present study was to perform a histologic analysis of the mucosa surrounding osseointegrated implant cover screws. For this study, 17 mucosal specimens were obtained from 12 patients during the second surgical session for implant exposure to the oral environment. After histologic preparation, specimens were sectioned perpendicularly to the mucosal surface to a thickness of about 3 µm, stained with 1% toluidine blue, and examined under light microscopy. All specimens showed a keratinized, stratified, squamous epithelium with well-defined strata. In the lamina propria, unorganized dense connective tissue was noted in the reticular layer, and in 4 samples, a chronic inflammatory infiltrate was seen in this region. The papillary layer presented tall connective papillae consisting of loose connective tissue. The results of this study confirm the hypothesis that the mucosa that conceals osseointegrated implant cover screws has the same morphologic characteristics as the alveolar masticatory mucosa. Furthermore, clinical conditions of normality in peri-implant tissues may not coincide with situations of histologic normality.

The aim of this study was to evaluate the influence of different periodontal therapies on the integrity of indirect restorations by scanning electron microscopy (SEM). Sixty single-rooted bovine teeth were selected and randomly assigned to 12 groups. Inlay cavities were prepared in the cervical region on the center of the cementoenamel junction, and were restored with laboratory processed resin and luted with a resin cement. Twelve periodontal therapies were used (n= 5): C: control (no treatment); MS: manual scaling with Gracey curettes; US: ultrasonic scaling; PP: prophylaxis with prophylactic paste; PS: prophylaxis with pumice-stone; SBJ: sodium bicarbonate jet; MS/PP; MS/PS; MS/SBJ; US/PP; US/PS; US/SBJ. The specimens were prepared and analyzed by SEM. SEM micrographs at ×100 to ×1000 magnification were obtained from the surface of the laboratory resin and the interface of the indirect restorations. The images were evaluated by 3 skillful, calibrated, blinded observers as to the presence of grooves, microcavities and fracture of margins. The results showed that PS produced groves on restoration surface. MS and US produced groves and marginal fractures on the restorations. SBJ resulted in resin cement degradation. These results suggest that except for PS, all procedures had deleterious effects on the marginal integrity of indirect restorations. O objetivo desse estudo foi avaliar a influência de diferentes terapias periodontais na integridade de restaurações indiretas por meio de microscopia eletrônica de varredura (MEV). Sessenta raízes bovinas foram selecionadas e aleatoriamente divididas em 12 grupos. Preparos cavitários inlay foram realizados na região cervical central da junção cemento-esmalte e restaurados com resina laboratorial cimentado com cimento resinoso. Doze terapias periodontais foram usadas (n=5): C-sem tratamento (controle); MS-raspagem manual com cureta Gracey; US-raspagem com ultra-som; PP- profilaxia com pasta profilática; PS-profilaxia com pedra pomes; SBJ-jato de bicarbonato; MS/PP; MS/PS; MS/SBJ; US/PP; US/PS; US/SBJ. As amostras foram preparados e submetidas a MEV. Imagens, de ×100 a ×1000, da superfície da resina laboratorial e da interface das restaurações indiretas foram obtidas. As imagens foram avaliadas em procedimento cego por 3 observadores habilitados previamente calibrados seguindo os seguintes critérios: ranhuras, microcavidades e fratura de margem. Os resultados mostraram que a profilaxia com pedra pomes promoveu ranhuras na superfície das restaurações. Raspagem manual e ultrasônica promoveram ranhuras e fratura de margem das restaurações. Jato de bicarbonato resultou em degradação de cimento resinoso. Os resultados sugeriram que, exceto a profilaxia com pasta profilática, todos os procedimentos resultaram em efeitos deletérios na integridade da margem das restaurações indiretas.

Purpose: To test the hypothesis that the type of cement used for fixation of cast dowel-and-cores might influence fracture resistance, fracture mode, and stress distribution of single-rooted teeth restored with this class of metallic dowels. Materials and Methods: The coronal portion was removed from 40 bovine incisors, leaving a 15 mm root. After endodontic treatment and standardized root canal relief at 10 mm, specimens were embedded in polystyrene resin, and the periodontal ligament was simulated with polyether impression material. The specimens were randomly divided into four groups (n = 10), and restored with Cu–Al cast dowel-and-cores cemented with one of four options: conventional glass ionomer cement (GI); resin-modified glass ionomer cement (GR); dual-cure resin cement (RC); or zinc-phosphate cement (ZP). Sequentially, fracture resistance of the specimens was tested with a tangential load at a 135° angle with a 0.5 mm/min crosshead speed. Data were analyzed using one-way analysis of variance (ANOVA) and the Fisher test. Two-dimensional finite element analysis (2D-FEA) was then performed with representative models of each group simulating a 100 μm cement layer. Results were analyzed based on von Mises stress distribution criteria. Results: The mean fracture resistance values were (in N): RC, 838.2 ± 135.9; GI, 772.4 ± 169.8; GR, 613.4 ± 157.5; ZP, 643.6 ± 106.7. FEA revealed that RC and GR presented lower stress values than ZP and GI. The higher stress concentration was coincident with more catastrophic failures, and consequently, with lower fracture resistance values. Conclusions: The type of cement influenced fracture resistance, failure mode, and stress distribution on teeth restored with cast dowel-and-cores.

This clinical study evaluated the influence of scaling and root planning (SRP), with and without the use of tetracycline-loaded bovine absorbent membrane, in the reduction of periodontal pockets according to 3 parameters: probing pocket depth (PPD), bleeding on probing (BOP) and plaque index (PI). Twenty-four patients were selected totalizing 144 random teeth divided in 2 groups (n=72 teeth) - control (SRP) and experimental (SRP with tetracycline-loaded absorbent membrane). PPD, BOP and PI were determined before and 28 days after the treatment. In all patients, the PPD values at the end of the treatment were always lower than the baseline values. There was a reduction of the PI for both treatments, but it was more evident on the experimental group. In conclusion, the use of tetracycline-loaded absorbent membrane could result in a better prognosis compared to scaling and root planning after only 28 days of evaluation. Este estudo clínico avaliou a influência da raspagem e alisamento radicular, com e sem a utilização de membrana absorvível de liberação de tetraciclina na redução de bolsa periodontal utilizando 3 parâmetros: sondagem da profundidade de bolsa, sangramento à sondagem e índice de placa. Vinte e quatro pacientes foram selecionados totalizando 144 dentes aleatoriamente divididos em 2 grupos (n=72 dentes) - controle (raspagem e alisamento radicular) e experimental (raspagem e alisamento radicular e utilização de membrana absorvível de liberação de tetraciclina). Antes da execução do tratamento foram determimados profundidade de bolsa, sangramento à sondagem e índice de placa. Os pacientes foram avaliados usando os mesmos parâmetros após 28 dias. Os valores da sondagem da profundidade de bolsa foram sempre menores no final do tratamento quando comparado ao início. Houve redução no índice de placa para as 2 formas de tratamento, apesar de ter sido mais evidente no grupo experimental. Concluiu-se que o uso da membrana absorvível de liberação de tetraciclina pode resultar em melhor prognóstico quando comparado apenas com a raspagem e alisamento radicular, após 28 dias de análise.

The aim of this study was to evaluate the effect of cavity design and glass fiber posts on stress distributions and fracture resistance of endodontically treated premolars. Fifty extracted intact mandibular premolars were divided into 5 groups (n = 10): ST, sound teeth (control); MOD, mesio-occlusal-distal preparation + endodontic treatment (ET) + composite resin restoration (CR); MODP, mesio-occlusal-distal + ET + glass fiber post + CR; MOD2/3, mesio-occlusal-distal + two thirds occlusal-cervical cusp loss + ET + CR; and MODP2/3, mesio-occlusal-distal + two thirds cusp loss + ET + glass fiber post + CR. The specimens were loaded on a cusp slope until fracture. Fracture patterns were classified according to four failure types. Stress distributions were evaluated for each group in a two-dimensional finite element analysis. The fracture resistance of the MODP, MOD2/3, and MODP2/3 groups was significantly lower than the ST and MOD groups (p < 0.05). The loss of dental structure and the presence of fiber post restoration reduced fracture resistance and created higher stress concentrations in the tooth-restoration complex. However, when there was a large loss of dental structure (MODP2/3), the post reduced the incidence of catastrophic fracture types.

Context: The prediction of implant treatment is directly influenced by the quality of the remaining bone after tooth extraction. Aims : The purpose of this experimental study was to, histologically and histometrically, evaluate the bone repair process in the central areas of extraction sockets filled with platelet-rich plasma. Materials and Methods: Four young adult male Cebus apella monkeys were used. The extraction of both right and left inferior second premolars was accomplished. After extraction, in one of the extraction sockets, coagulum was maintained while in the other it was removed; the alveolus was dried with gauze compress and filled up with platelet concentrate. For PRP production, Sonnleitner's protocol was followed. The specimens for histological and histometric assessment were obtained in 30, 90, 120 and 180 days intervals. Results: In 30 days new bone formation was intense in both experimental and control sockets and no significant differences were observed between the two groups. After 90 days of the extraction, while the control group showed signs of decrease in osteogenesis, in the experimental unit, the process of bone formation and fibroblast-like cell proliferation remained intense. After 120 days, the PRP treated socket was occupied by large trabeculae of bone. After 180 days, the control unit was occupied mostly with bone marrow. The experimental unit remained occupied with large amounts of bone tissue. Conclusions: It was possible to conclude that bone repair was enhanced by the use of platelet- rich plasma in alveolar sockets.

Objectives: Specific physical and chemical features of the membranes may influence the healing of periodontal tissues after guided tissue regeneration (GTR). The aim of the present investigation was to analyze the biological effects of three bioabsorbable membranes. The hypothesis is that all tested membranes present similar biological effects. Methods: Human osteoblast like-cells (SaOs-2) and gingival fibroblasts FGH (BCRJ -RJ) were cultured in DMEM medium. The viability of the cells cultured on the membranes was assesses using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). Quantitative determination of activated human Transforming Growth Factor beta 1 (TGF-β1) on the supernatants of the cell culture was observed. Samples were examined using scanning electron microscope (SEM). Results: SaOs2, in 24 hours, PLA group showed higher values when compared to other groups (P < 0.05). All groups presented statistical significance values when compared two times. In 4 h and 24 h, for the fibroblasts group, significantly difference was found to PLA membrane, when compared with the other groups (p < 0.05). For TGFβ1 analyzes, comparing 4 and 24 h, for the osteoblast supernatant, COL1 and PLA groups showed statistically significant difference (p