Use of Buccal Fat Pad in the Treatment of Peri-Implant Mucosal Defect: A Case Report.

The present study describes a clinical case in which the buccal fat pad (BFP) was used to improve the contour of the peri-implant mucosa. To our knowledge, this is the first case report of such an application in the literature. A 58-year-old woman presented with teeth #2 and #3 missing and an indication for extraction of tooth #4. After clinical examination and CBCT analysis, immediate implants were placed in the region of the extracted tooth and that of tooth #2 for prosthetic rehabilitation using a three-unit fixed partial denture. There was an extensive mucosal defect in the region of tooth #3, with vertical and horizontal changes in the contour of the mucosa. As an alternative to the use of a subepithelial connective tissue graft, we opted for displacement of the BFP and its accommodation on the alveolar ridge of tooth #3 to improve the buccal tissue contour. After 5 years of follow-up, satisfactory gain and maintenance of mucosal volume were observed in the treated area, as well as improvement of buccal tissue contour. The use of BFP seems to be a feasible alternative for filling and treating peri-implant mucosal defects.

A large dentigerous cyst treated with decompression and orthosurgical traction: a case report.

This article presents the case of an 8-year-old patient who presented with a large radiolucency associated with the maxillary left canine and a supernumerary tooth. A computed tomography scan showed the radiolucency was in close proximity to the roots of the anterior teeth, with no areas of root resorption, and expansion into the left maxillary sinus. The boundaries of the maxillary sinus floor were still preserved. After positive aspiration of intralesional liquid and due to the large size of the radiolucency, a decompression technique was selected to preserve the permanent canine. Surgery was performed to remove the supernumerary tooth, followed by orthodontic treatment and surgery to allow access for orthodontic traction of the permanent canine. More than 5 years post-treatment, no recurrence was observed and the therapeutic option to position and preserve the permanent canine was successful.

Peroxide penetration from the pulp chamber to the external root surface after internal bleaching.

PURPOSE: To quantify the amount of peroxide penetration from the pulp chamber to the external surface of teeth during the walking bleaching technique. METHODS: Seventy-two bovine lateral incisors were randomly divided over five experimental groups and one control (n = 12 per group): (1) 35% hydrogen peroxide (HP); (2) 35% carbamide peroxide (CP); (3) sodium perborate (SP); (4) (HP+SP); (5) (CP+SP) and (6) Control (CG), deionized water. All groups were treated according to the walking bleach technique. After 7 days at 37 degrees C in an acetate buffer solution, 100 microl violet leukocrystal coloring and 50 microl peroxidase was added, producing a blue stain that could be measured in a spectrophotometer and then converted into peroxide microg/ml. RESULTS: G5 exhibited the greatest penetration, while G2 and G3 produced the lowest values. All bleaching agents penetrated from the pulp chamber to the external root surface. There was a direct correlation between the presence of oxidative agents and penetration potential. Sodium perborate in distilled water was less oxidative and appeared to be the least aggressive bleaching agent.

Influence of osteopenia in autogenous bone graft healing with or without expanded polytetrafluoroethylene membranes: histologic and histomorphometric study in rats.

PURPOSE: The aim of this study was to quantitatively evaluate and qualitatively describe autogenous bone graft healing with or without an expanded polytetrafluoroethylene (e-PTFE) membrane in ovariectomized rats. MATERIALS AND METHODS: Eighty Wistar rats, weighing approximately 300 g each, were used. A graft was obtained from the parietal bone and fixed to the sidewall of each animal's left mandibular ramus. The animals were randomly divided into four experimental groups (n = 20 in each group): group 1, sham operated and autogenous bone graft only; group 2, sham operated and autogenous bone graft covered by e-PTFE membrane; group 3, ovariectomized (OVX) and autogenous bone graft only; group 4, OVX and autogenous bone graft covered by e-PTFE membrane. The animals were sacrificed at five different time points: immediately after grafting or at 7, 21, 45, or 60 days after grafting. Histologic examination and morphometric measurement of the sections were performed, and values were submitted to statistical analyses. RESULTS: Both groups (sham and OVX) experienced loss of the original graft volume when it was not covered by the membrane, whereas use of the membrane resulted in additional bone formation beyond the edges of the graft and under the membrane. Histologic analysis showed integration of the grafts in all animals, although a larger number of marrow spaces was found in OVX groups. CONCLUSIONS: Association of bone graft with an e-PTFE membrane resulted in maintenance of its original volume as well as formation of new bone that filled the space under the membrane. Osteopenia did not influence bone graft repair, regardless of whether or not it was associated with e-PTFE membrane, but descriptive histologic analysis showed larger numbers of marrow spaces in the bone graft and receptor bed and formation of new bone in the OVX animals.

Bone grafting and osseointegration in the area of maxillary tooth agenesis. Case report / Incorporação de enxertos ósseos e osseointegração em área de agenesia dentária maxilar. Caso clínico

The high dental implant success rate is directly linked to the presence of adequate bone volume, which enables and maintains the osseointegration of dental implants. This study aimed to report a clinical case of a female with agenesis of the right maxillary lateral incisor (12), due to cleft lip and palate. Because the bone and mucosal defects of the area, the treatment planning comprised guided bone regeneration with the association of autogenous bone, platelet rich plasm (PRP), and expanded polytetrafluoroethylene membrane (e-PTFE,Gore-Tex), performed in 2005. After nine months, a new evaluation was carried out and revealed that the area was still not suitable for implant placement. Thus, an allogenous bone graft was planned. Elapsed another nine months, the implant was placed. After six months, the implant was reopened and a metal-ceramic crown was installed. The 5-year following-up appointment showed the presence of fistula with purulent secretion at the buccal cortical plate. We attempted to control the fistula with antibiotics and follow-up clinically and radiographically. The examinations suggested a communication with the right nasal cavity, which decreased until nowadays. The osseointegrated dental implant was in function, without symptomatology. The autogenous bone graft is still more effective than allogenous bone graft. Further studies are necessary to achieve better evaluations. (AU)

A realização de elevadas taxas de sucesso em implantodontia está diretamente ligada à presença de volume de tecido ósseo adequado, que permiti e mantém a osseointegração dos implantes dentários. O objetivo deste trabalho foi apresentar o caso clínico da paciente, com agenesia do dente 12, decorrente da fissura lábio-palatina. Devido ao defeito ósseo e mucoso na região, foi planejada a realização da técnica de regeneração óssea guiada, associando a utilização de osso autógeno, plasma rico em plaquetas (PRP) e membrana de politetrafluoretileno expandido (PTFE-e, Gore-Tex) realizado em 2005. Após 9 meses, nova avaliação foi realizada, porém a área estava inadequada para o posicionamento do implante, optou-se por um novo enxerto, agora alógeno. E após mais 9 meses foi instalado o implante. Aguardou-se 6 meses até a reabertura, para o implante entrar em função por meio de uma coroa metalocerâmica. Passados 5 anos de controle a paciente apresentou uma fístula com secreção purulenta na parede óssea vestibular, controlada com terapia medicamentosa, e após alguns anos, pelo exame clínico e tomográfico, sugeriu-se comunicação com a cavidade nasal direita, porém regrediu e está sendo preservada até os dias atuais, com o implante osseointegrado em função, sem sintomatologia. O enxerto ósseo autógeno ainda é superior em relação ao alógeno. Outros estudos são necessários para melhores avaliações. (AU)

Resistance to compression of weakened roots subjected to different root reconstruction protocols.

OBJECTIVE: This study evaluated, in vitro, the fracture resistance of human non-vital teeth restored with different reconstruction protocols. MATERIAL AND METHODS: Forty human anterior roots of similar shape and dimensions were assigned to four groups (n=10), according to the root reconstruction protocol: Group I (control): non-weakened roots with glass fiber post; Group II: roots with composite resin by incremental technique and glass fiber post; Group III: roots with accessory glass fiber posts and glass fiber post; and Group IV: roots with anatomic glass fiber post technique. Following post cementation and core reconstruction, the roots were embedded in chemically activated acrylic resin and submitted to fracture resistance testing, with a compressive load at an angle of 45º in relation to the long axis of the root at a speed of 0.5 mm/min until fracture. All data were statistically analyzed with bilateral Dunnett's test (α=0.05). RESULTS: Group I presented higher mean values of fracture resistance when compared with the three experimental groups, which, in turn, presented similar resistance to fracture among each other. None of the techniques of root reconstruction with intraradicular posts improved root strength, and the incremental technique was suggested as being the most recommendable, since the type of fracture that occurred allowed the remaining dental structure to be repaired. CONCLUSION: The results of this in vitro study suggest that the healthy remaining radicular dentin is more important to increase fracture resistance than the root reconstruction protocol.

Evaluation of morphological and chemical alterations in enamel, dentin and cementum after internal bleachingtechnique using different bleaching agents / Avaliação das alterações químicas e morfológicas em esmalte, dentina e cemento após clareamento interno usando diferentes clareadores

Objetivo: O objetivo deste estudo foi avaliar as alterações químicas e morfológicas em esmalte, dentina e cemento após clareamento interno utilizando microscopia eletrônica de varredura e espectrometria de energia dispersiva. Materiais e Métodos: Setenta e dois incisivos bovinos foram preparados, cortados e clareados por 7 dias com os seguintes agentes clareadores: PH: gel de peróxido de hidrogênio 35%; PH + PS: gel de peróxido de hidrogênio 35% + perborato de sódio; PC: gel de peróxido de carbamida 37%; PC + PS: gel de peróxido de carbamida 37% + perborato de sódio; PS: perborato de sódio + água; e Controle: água deionizada. Os espécimes foram seccionados e preparados para análise em microscopia eletrônica de varredura e análise dos níveis de cálcio, fósforo, oxigênio e carbono usando espectrometria de energia dispersiva. Resultados: Foi observada uma redução significante nos níveis de cálcio em esmalte após clareamento com PC + PS e PC (p < 0,05). Os níveis de carbono (parte orgânica) foram alterados em esmalte. Uma redução significante nos níveis de cálcio foi encontrada na dentina nos grupos PH + PS, PC e PC + PS. Os níveis de fósforo aumentaram após o uso de PS (p < 0,05) e PC (p < 0,05). Níveis de carbono mostraram pequena variação e a maior quantidade foi encontrada nos grupos PC e PC + PS (p < 0,05), nos outros grupos não houve alteração. Uma redução significante nos níveis de cálcio foram encontradas no cemento no grupo PC + PS (p < 0,05). Conclusão: Alterações em esmalte, dentina e cemento ocorreram após o clareamento e essas alterações foram menos significantes quando utilizado perborato de sódio e água

Objective: The aim of this study was to evaluate the morphological and chemical alterations in enamel, dentin and cementum after internal bleaching using scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS). Material and Methods: Seventy-two bovine incisor teeth were prepared, cut and bleached for 7 days as follows: HP: 35% hydrogen peroxide gel; HP+SP: 35% hydrogen peroxide gel + sodium perborate; CP: 37% carbamide peroxide gel; CP+SP: 37% carbamide peroxide gel + sodium perborate; SP: sodium perborate + water; and control: deionized water. The specimens were sectioned and prepared for morphological analysis under SEM and analysis of calcium, phosphorus, oxygen and carbon levels using EDS. Results: A significant reduction was found in the calcium levels in enamel after treatment with CP + SP and CP (p < 0.05). Carbon (organic part) was hardly altered in enamel. A significant reduction in the calcium levels was found in dentin in Groups HP+SP, CP and CP+SP. Phosphorus levels increased after SP+H20 (p < 0.05) and CP (p < 0.05). Carbon levels showed little variation and the largest amount was found in Groups CP and CP+SP (p < 0.05); in the other groups there was no alteration. A significant reduction in the calcium levels was found in the cementum in Group CP+SP (p < 0.05). Conclusion: Alterations in the enamel, dentin and cementum compositions occurred after bleaching and these alterations showed to be less significant with sodium perborate and water.

Hemodynamic evaluation of normotensive and hypertensive patients undergoing dental extraction under local anesthesia with 3% prilocaine with felypressin / Avaliação hemodinâmica de pacientes normotensos e hipertensos submetidos à exodontia sob anestesia local com cloridrato de prilocaína 3% associado à felipressina

Objetivo: Este estudo avaliou as alterações hemodinâmicas de pacientes normotensos e hipertensos submetidos a exodontia de dentes normalmente implantados sob ação do anestésico local cloridrato de prilocaina 3%, com felipressina 0,03UI/ml. Material e Métodos: Foram avaliados 49 pacientes do ambulatório da Disciplina de Cirurgia e Traumatologia Buco-Maxilo-Facial do Curso de Odontologia do Instituto de Ciência e Tecnologia da Universidade Estadual Paulista ‘’Julio de Mesquita Filho” campus de São Jose dos Campos, sendo 30 normotensos e 19 hipertensos que deveriam ter no momento da avaliação inicial pressão sistólica até 160 mmHg e diastólica até 100 mmHg além de estarem sob acompanhamento médico. Os pacientes foram submetidos a exodontia de molares ou pré-molares normalmente implantados, com grau máximo de mobilidade 2, segundo a classificação de Miller. Os parâmetros avaliados foram pressão arterial sistólica, diastolica e frequência cardíaca, por meio de um aparelho digital automático de pulso, nos seguintes períodos: T1 - inicial (5 min antes do início da cirurgia, com o paciente sentado); T2 – pós-anestesia (após 2 min da administração do anestésico); T3 – trans-operatório (a cada 5 min após a aferição em T2 até completar 20 minutos, totalizando 4 mensurações trans-operatórias); T4 – pós-cirurgia ( 5 min após a remoção dos campos cirúrgicos). Resultados: A análise estatística demonstrou que para os parâmetros pressão arterial sistólica (P = 0,959) e pressão arterial diastólica (P = 0,754) não houve diferença estatística significante para estes parâmetros nos diferentes períodos de avaliação. A análise dos valores de frequência cardíaca demonstrou haver diferença estatística (p < 0,05) entre os valores obtidos em T1 nos pacientes hipertensos e T3.3 nos pacientes normotensos...

Objective: this study evaluated hemodynamic variations of normotensive and hypertensive patients undergoing dental extraction under local anesthesia with 3% prilocaine with 0.03 UI/ml felypressin. Material and Methods: Forty-nine patients from the Department of Surgery and Maxillo-facial Traumatology ambulatory were evaluated. Thirty were normotensive and 19 hypertensive; they presented initial systolic blood pressure lower than 160 mmHg and diastolic blood pressure lower than 100 mmHg, besides being under medical supervision. Patients underwent molar or premolar extraction, typically deployed with maximum degree of mobility 2, according to Miller’s classification. The parameters evaluated were systolic and diastolic blood pressures and heart rate, using an automatic digital pulse device, in the following periods: T1 - Initial (5 min before the beginning of surgery, with the patient seated); T2 - post-anesthesia (after 2 min of anesthetic administration); T3 - trans-operative (every 5 min after the measurement T2 to complete 20 min, totaling 4 trans-operative measurements); T4 - after surgery (5 min after removal of the surgical field). Results: statistical analysis showed for the parameters systolic blood pressure (P = 0.959) and diastolic blood pressure (P = 0.754), no statistically significant difference for these parameters in different evaluation periods. The analysis of heart rate values showed statistical difference (p < 0.05) between the values obtained in T1 in hypertensive and normotensive patients in T3.3. Conclusion: it was concluded that the evaluated hemodynamic parameters varied in different periods evaluated in group of normotensive and hypertensive patients, but did not differ significantly.

Penetration of 35% hydrogen peroxide into the pulp chamber in bovine teeth after LED or Nd:YAG laser activation.

This aim of the present study was to evaluate the pulp chamber penetration of 35% hydrogen peroxide activated by LED (light-emitting diode) or Nd:YAG laser in bovine teeth, after an in-office bleaching technique. Forty-eight bovine lateral incisors were divided into four groups, acetate buffer was placed into the pulp chamber and bleaching agent was applied as follows: for group A (n = 12), activation was performed by LED; for group B (n = 12), activation was performed by Nd:YAG laser (60 mJ, 20 Hz); group C (n = 12) received no light or laser activation; and the control group (n = 12) received no bleaching gel application or light or laser activation. The acetate buffer solution was transferred to a glass tube and Leuco Crystal Violet and horseradish peroxidase were added, producing a blue solution. The optical density of this solution was determined spectrophotometrically and converted into microgram equivalents of hydrogen peroxide. The results were analysed using ANOVA and Tukey's test (5%). It was verified that the effect of activation was significant, as groups activated by LED or laser presented greater hydrogen peroxide penetration into the pulp chamber (0.499 +/- 0.622 microg) compared with groups that were not (0.198 +/- 0.218 microg). There was no statistically significant difference in the penetration of hydrogen peroxide into the pulp chamber between the two types of activation (LED or laser). The results suggest that activation by laser or LED caused an increase in hydrogen peroxide penetration into the pulp chamber.

Cytotoxicity of non-vital dental bleaching agents in human gingival fibroblasts / Avaliação da citotoxicidade de agentes clareadores de uso interno sobre fibroblastos gengivais humanos

Objective: The aim of this study was to compare several non-vital dental bleaching agents for their in vitro cytotoxicity to human gingival fibroblasts primary cell line. Methods: The cells were cultivated in DMEM and were seed in plates of 96 wells; then, it was exposed to the conditioned medium according to the experimental groups (n = 12): G1 - SP (sodium perborate) + distilled water; G2 - SP + 20% CP (carbamide peroxide); G3 - 20% CP; G4 - SP + 35% HP (hydrogen peroxide); G5 - 35% HP. In the control group (n = 12), corresponded to the curve of cell growth and viability, the cells did not receive any treatment. Cell viability was measured photometrically using a MTT assay after a 24 h and 48 h of exposure period. Data were submitted to ANOVA and Tukey’s tests. Results: All the experimental groups presented high cytotoxicity statically in comparison to the control group. The rank of the most to the least toxic material after 24 h was: SP + DW > 35% PH > PS + 20% PC > PS + 35% PH > 20% PC; and after 48 h was: SP + DW > PS + 20% PC > 35% PH > PS + 35% PH > 20% PC. Conclusion: All the bleaching agents had presented cytotoxicity effects, reducing significantly the cell viability, however, in the conditions that the study was conducted the association of sodium perborate with distilled water was the most toxic bleaching agent

Objetivo: O objetivo deste estudo foi comparar a citotoxicidade de agentes clareadores de uso interno em linhagem primária de fibroblastos humanos. Material e Método: As células foram cultivadas em meio DMEM e semeadas em placas de 96 poços. Em seguida, foram expostas aos meios de cultura condicionados de acordo com os grupos experimentais (n = 12): G1 - PS (perborato de sódio) + água destilada; G2 - PS + PC 20% (peróxido de carbamida); G3 - PC 20% ; G4 - PS + PH 35% (peróxido de hidrogênio); G5 - PH 35%. No grupo controle (n = 12), correspondente à curva de crescimento e viabilidade celular, as células não receberam nenhum tratamento. A viabilidade celular foi verificada por espectofotômetro utilizando o ensaio de MTT, após um período de 24 e 48 h de exposição aos agentes clareadores. Os dados foram submetidos aos testes de ANOVA e Tukey. Resultados: Todos os grupos experimentais apresentaram alta citotoxicidade em relação ao grupo controle. O rank de citotoxicidade dos agestes clareadores após 24 h foi: PS + AD > PH 35% > PS + PC 20% > PS + PH 35% > PC 20% e após 48h foi: PS + AD > PS + PC 20%> 35% PH > PS +PH 35% > 20% PC. Conclusão: Todos os agentes clareadores apresentaram efeitos citotóxicos, reduzindo significativamente a viabilidade da celular. Entretanto, nas condições em que o estudo foi conduzido a associação do perborato de sódio com água destilada, foi o agente clareador mais tóxico

Resistance to compression of weakened roots subjected to different root reconstruction protocols

OBJECTIVE: This study evaluated, in vitro, the fracture resistance of human non-vital teeth restored with different reconstruction protocols. MATERIAL AND METHODS: Forty human anterior roots of similar shape and dimensions were assigned to four groups (n=10), according to the root reconstruction protocol: Group I (control): non-weakened roots with glass fiber post; Group II: roots with composite resin by incremental technique and glass fiber post; Group III: roots with accessory glass fiber posts and glass fiber post; and Group IV: roots with anatomic glass fiber post technique. Following post cementation and core reconstruction, the roots were embedded in chemically activated acrylic resin and submitted to fracture resistance testing, with a compressive load at an angle of 45º in relation to the long axis of the root at a speed of 0.5 mm/min until fracture. All data were statistically analyzed with bilateral Dunnett's test (α=0.05). RESULTS: Group I presented higher mean values of fracture resistance when compared with the three experimental groups, which, in turn, presented similar resistance to fracture among each other. None of the techniques of root reconstruction with intraradicular posts improved root strength, and the incremental technique was suggested as being the most recommendable, since the type of fracture that occurred allowed the remaining dental structure to be repaired. CONCLUSION: The results of this in vitro study suggest that the healthy remaining radicular dentin is more important to increase fracture resistance than the root reconstruction protocol.

Mini-implante dentário como alternativa terapêutica para resolução de agenesia de incisivo lateral com cirurgia flapless e provisionalização imediata: relato de caso com 84 meses de acompanhamento / Mini dental implant as an alternative therapy for lateral incisor agenesis with flapless surgery and immediate provisionalization a case report with 84 months of follow-up

O presente estudo apresenta um caso de paciente do gênero masculino, 18 anos de idade, com agenesia do elemento 12, que optou pela utilização de um mini-implante associado à técnica de cirurgia sem retalho e realização de provisionalização imediata. Foi realizado acompanhamento clínico semanal no primeiro mês pós-implantação, não tendo sido observada qualquer complicação, assim como nos controles mensais seguintes, demonstrando sucesso nos resultados estéticos e funcionais. Após seis meses, a reabilitação protética foi finalizada com uma coroa In-Ceram e reabilitação cosmética do sorriso. O presente caso ressalta a importância do correto planejamento protético-cirúrgico, a experiência do profissional e os acompanhamentos clínicos de longo prazo

This case report illustrates a 18 years-old male patient with agenesis of tooth 22 receiving a mini dental implant with flapless surgery and immediate provisionalization. Postoperative control was performed every week in the first month and monthly thereafter demonstrating esthetic and functional success. Six months later, an In-Ceram crown was delivered for cosmetic smile design. This case highlights the importance of adequate surgical and prosthetic procedures, professional experience, and long-term clinical follow-ups.

Atividade antimicrobiana de um EDTA gel associado a peróxido de hidrogênio sobre cepas clínicas de Candida albicans / Antimicrobial activity of gel EDTA associated with hydrogen peroxide on clinical isolates of Candida albicans

O presente trabalho teve como objetivo analisar a atividade antimicrobiana de um produto composto por EDTA gel associado a peróxido de hidrogênio (Canal Plus®) sobre amostras clínicas de Candida albicans, utilizando o método de diluição em caldo. Foram incluídos no estudo isolados bucais e amostra padrão de Candida albicans (ATTC 18804). O Canal Plus foi diluído em caldo BHI em placas de microtitulação, obtendo-se as concentrações finais de 50% a 0,02%. O hipoclorito de sódio 2,5% foi utilizado como controle positivo. Após, foi adicionado suspensão padronizada de Candida albicans e as placas foram incubadas a 37ºC por 24 horas. Foram determinadas diluição inibitória mínima(DIM) e diluição fungicida mínima (DIF). O Canal Plus® foi capaz de inibir todas as cepas clínicas a partir da diluição 0,75%. Considerando os resultados obtidos, os dados sugerem que o Canal Plus tem eficiente atividade antimicrobiana sobre cepas clínicas de Candida albicans.

The purpose of this study was to analyze the antimicrobial activity of a composed product for EDTA gel associated with hydrogen peroxide (Plus® Canal) on clinical isolates of Candida albicans, using the method of dilution in broth. They had been enclosed in the study clinical isolates and reference strain of Candida albicans (ATTC 18804). The Plus Canal was diluted in broth BHI in microtitulation plates, obtaining the final concentrations of 50% to 0.02%. The sodium hypochlorite 2.5% was used as positive control. After, standardized suspension of Candida albicans was added and the plates had been stored in an oven at 37º C for 24 hours. Minimal inhibitory dilution and minimal fungicidal dilution had been determined. The Plus® Canal was capable to inhibit all clinical isolates from dilution 0.75%. Considering the results, the data suggest that the Canal Plus has efficient antimicrobial activity on clinical isolates of Candida albicans.

Avaliação da citotoxicidade de agentes clareadores para uso caseiro e profissional / Evaluation of cytotoxicity of different bleaching agents for nightguard vital bleaching and office bleach technique in vitro

A proposta deste estudo foi avaliar a citotoxicidade dos peróxidos de hidrogênio (PH) e carbamida (PC), para uso caseiro e profissional, sobre cultura de fibroblastos de mucosa de tecido gengival humano (FMM1). As células utilizadas foram cultivadas em DMEM e após 24 horas foi colocado meio de cultivo condicionado com os agentes clareadores: G1- PC 35% sem fotoativação (SF); G2- PC 35% ativado por luz halógena; G3- PC 35% ativado por diodo emissor de luz (LED); G4- PC 37% SF; G5- PC 37% ativado por luz halógena; G6- PC 37% ativado por LED; G7- PH 3% SF; G8- PH 7,5% SF; G9- PH 9,5% SF; G10- PC 10% SF; G11- PC 15% SF e G12- PC 20% SF. Uma curva padrão de viabilidade celular foi obtida a partir de células que não receberam tratamento (controle). O ensaio com MTT foi realizado após 24 e 48 horas, para avaliar a viabilidade celular. Paralelamente, foi medido colorimetricamente a quantidade de PH liberado nas condições experimentais. Os dados da viabilidade celular obtidos foram analisados estatisticamente através dos testes ANOVA e Tukey, (p<0,05). Todos os grupos apresentaram diferença significativa em relação ao controle. Dentre os agentes clareadores para uso profissional o PC 37% apresentou maior citotoxicidade e quantidade de peróxido de hidrogênio liberada que o PC 35%. A ativação por luz halógena ocasionou maior citotoxicidade e maior quantidade de PH liberado. Dentre os agentes clareadores para uso caseiro a base de peróxido de hidrogênio houve uma maior taxa de sobrevivência celular na concentração mais baixa de peróxido de hidrogênio (PH 3%); nos clareadores a base de peróxido de carbamida houve uma maior taxa de sobrevivência celular na concentração mais baixa de peróxido de carbamida (PC 10%). A taxa de sobrevivência celular foi significantemente menor após 48 horas. Concluiu-se que a citotoxicidade foi proporcional à concentração do agente clareador e que a fotoativação com luz halógena aumentou a liberação de peróxido de hidrogênio.

The purpose of this study was to evaluate the citotoxicity of hydrogen peroxide (HP) and carbamide peroxide (CP) on fibroblasts from mucosa of human gingival tissue (FMM1). The cells were cultivated in DMEM and was placed in contact with conditioned medium with bleaching agents: G1- 35% CP without curing, G2-35% CP activated by halogen light; G3- 35% CP activated by light emission diode (LED); G4- 37% CP without curing; G5- 37% CP activated by halogen lamp; G6- 37% CP activated by LED; G7- 3% HP without curing; G8-7.5% HP without curing; G9 - 9.5% HP without curing; G10- 10% CP without curing, G11-15% CP without curing, and G12- 20% CP without curing. A standard curve of cell growth and viability was obtained from cells that received no treatment (control). The MTT test was performed after 24 and 48 hours to assess the viability and cell growth. In parallel, was measured the amount of PH released under the experimental conditions. The data of cell viability were statistically analyzed by ANOVA and Tukey’s tests (p <0.05). All groups showed significant differences in relation to the control group. Among the bleaching agents for office application, the 37% CP showed higher cytotoxicity and the 35% CP released the higher quantity of hydrogen peroxide. The activation by halogen light promoted the higher cytotoxicity and higher HP released. Among the home bleaching agents based on hydrogen peroxide there was a higher rate of cell survival in low concentration of hydrogen peroxide (3% HP); the bleaching based on carbamide peroxide had a higher cell survival rate in low concentration of carbamide peroxide (CP 10%). The cell viability was significantly lower after 48 hours. It was concluded that the cytotoxicity was related to the concentration of bleaching agent and the curing with halogen light increased the hydrogen peroxide release.