TiO2 nanotube-containing glass ionomer cements display reduced aluminum release rates.

Titanium dioxide nanotubes (TiO2-nts) were incorporated into a glass ionomer cement (GIC) with improved mechanical properties and antibacterial activity. The aims of the present in vitro study were to define the elemental characterization, aluminum (Al) release rate, and initial working time for GIC reinforced with TiO2-nts, in an experimental caries model. TiO2-nts were incorporated into GIC powder components at 5% by weight, and compared with unblended GIC. Experimental approaches used energy-dispersive spectrometry (EDS), atomic absorption spectrophotometry (AAS), and brightness loss to define surface element properties, Al release rates, and initial working time, respectively. Statistical analysis was performed by 2-way ANOVA, Tukey's test, generalized linear models, and Student's t test (a = 0.05). EDS data analysis revealed that TiO2-nts incorporated into GIC had no significant impact on the typical elemental composition of GICs in an in vitro caries model. Regarding the demineralizing solution, GIC with TiO2-nt significantly decreased the Al release rate, compared with the control group (p < 0.0001). Moreover, TiO2-nt incorporated into GIC did not alter the initial working time of the material (p > 0.05). These findings add information to our scientific body of knowledge concerning the potential impact of TiO2-nt on the performance of conventional GICs.

TiO2 nanotube-containing glass ionomer cements display reduced aluminum release rates

Abstract Titanium dioxide nanotubes (TiO2-nts) were incorporated into a glass ionomer cement (GIC) with improved mechanical properties and antibacterial activity. The aims of the present in vitro study were to define the elemental characterization, aluminum (Al) release rate, and initial working time for GIC reinforced with TiO2-nts, in an experimental caries model. TiO2-nts were incorporated into GIC powder components at 5% by weight, and compared with unblended GIC. Experimental approaches used energy-dispersive spectrometry (EDS), atomic absorption spectrophotometry (AAS), and brightness loss to define surface element properties, Al release rates, and initial working time, respectively. Statistical analysis was performed by 2-way ANOVA, Tukey's test, generalized linear models, and Student's t test (a = 0.05). EDS data analysis revealed that TiO2-nts incorporated into GIC had no significant impact on the typical elemental composition of GICs in an in vitro caries model. Regarding the demineralizing solution, GIC with TiO2-nt significantly decreased the Al release rate, compared with the control group (p < 0.0001). Moreover, TiO2-nt incorporated into GIC did not alter the initial working time of the material (p > 0.05). These findings add information to our scientific body of knowledge concerning the potential impact of TiO2-nt on the performance of conventional GICs.

Influence of rs6667202 SNP on Interleukin-10 levels in the gingival fluid of patients with periodontitis grade C

Grade C periodontitis in youngers is characterized by a severe form of periodontitis, and IL10 rs6667202 single nucleotide polymorphism (SNP) has been described as an important feature in this disease etiology. Aim: This study aimed to evaluate, in vivo, the functionality of IL10 rs6667202 SNP on IL-10 gingival fluid levels. Methods: Thirty patients with Perio4C were selected, 15 with the IL10 AA genotype (rs6667202) and 15 with AC/CC genotypes. The gingival fluid was collected from two sites with probing depth ≥ 7 mm and bleeding on probing, and two healthy sites. The IL-10 concentration was determined by Luminex/MAGpix platform. Results: In deep pockets, the IL10 AA genotype presented a lower concentration of IL-10 when compared with AC or CC genotypes (p<0.05). In shallow pockets, no difference between groups was seen (p>0.05). Conclusion: IL10 rs6667202 SNP decreases the production of IL-10 in crevicular fluid, potentially affecting this disease progression

Titanium dioxide nanotubes added to glass ionomer cements affect S. mutans viability and mechanisms of virulence

Abstract This in vitro study evaluated the impact of TiO2 nanotubes (n-TiO2) incorporated into glass ionomer cement (GIC) on Streptococcus mutans (S. mutans) characteristics at cellular and molecular levels. n-TiO2, synthesized by the alkaline method (20 nm in size), was added to Ketac Molar EasyMix® at 0%, 3%, 5%, and 7% by weight. S. mutans strains were cultured on GIC disks with addition or not of n-TiO2 for 1, 3, and 7 days and the following parameters were assessed: inhibition halo (mm) (n=3/group); cell viability (live/dead) (n=5/group); cell morphology (SEM) (n=3/group); and gene expression by real-time PCR (vicR, covR, gtfB, gtfC, and gtfD) (n=6/group). The data were analyzed by the Kruskal-Wallis test, repeated-measures ANOVA or two-way ANOVA, and Tukey's and Dunn's post-hoc tests (α=0.05). The agar diffusion test showed a higher antibacterial property for 5% n-TiO2 compared with 3% and 7% (p<0.05) with no effect of time (1, 3, and 7 days). The cell number was significantly affected by all n-TiO2 groups, while viability was mostly affected by 3% and 5% n-TiO2, which also affected cell morphology and organization. Real-time PCR demonstrated that n-TiO2 reduced the expression of covR when compared with GIC with no n-TiO2 (p<0.05), with no effect of time, except for 3% n-TiO2 on vicR expression. Within-group and between-group analyses revealed n-TiO2 did not affect mRNA levels of gtfB, gtfC, and gtfD (p>0.05). Incorporation of n-TiO2 at 3% and 5% potentially affected S. mutans viability and the expression of key genes for bacterial survival and growth, improving the anticariogenic properties of GIC.

Transcriptome profile of highly osteoblastic/cementoblastic periodontal ligament cell clones

Abstract Heterogeneous cell populations of osteo/cementoblastic (O/C) or fibroblastic phenotypes constitute the periodontal dental ligament (PDL). A better understanding of these PDL cell subpopulations is essential to propose regenerative approaches based on a sound biological rationale. Objective Our study aimed to clarify the differential transcriptome profile of PDL cells poised to differentiate into the O/C cell lineage. Methodology To characterize periodontal-derived cells with distinct differentiation capacities, single-cell-derived clones were isolated from adult human PDL progenitor cells and their potential to differentiate into osteo/cementoblastic (O/C) phenotype (C-O clones) or fibroblastic phenotype (C-F clones) was assessed in vitro. The transcriptome profile of the clonal cell lines in standard medium cultivation was evaluated using next-generation sequencing technology (RNA-seq). Over 230 differentially expressed genes (DEG) were identified, in which C-O clones showed a higher number of upregulated genes (193) and 42 downregulated genes. Results The upregulated genes were associated with the Cadherin and Wnt signaling pathways as well as annotated biological processes, including "anatomical structure development" and "cell adhesion." Both transcriptome and RT-qPCR showed up-regulation of WNT2, WNT16, and WIF1 in C-O clones. Conclusions This comprehensive transcriptomic assessment of human PDL progenitor cells revealed that expression of transcripts related to the biological process "anatomical structure development," Cadherin signaling, and Wnt signaling can identify PDL cells with a higher potential to commit to the O/C phenotype. A better understanding of these pathways and their function in O/C differentiation will help to improve protocols for periodontal regenerative therapies.

Isolation and characterization of a human cementocyte-like cell line, HCY-23

Abstract Cementum is the mineralized tissue covering the tooth root that functions in tooth attachment and post-eruptive adjustment of tooth position. It has been reported to be highly similar to bone in several respects but remains poorly understood in terms of development and regeneration. Here, we investigate whether cementocytes, the residing cells in cellular cementum, have the potential to be protagonist in cementum homeostasis, responding to endocrine signals and directing local cementum metabolism. Cells from healthy erupted human teeth were isolated using sequential collagenase/EDTA digestions, and maintained in standard cell culture conditions. A cementocyte-like cell line was cloned (HCY-23, for human cementocyte clone 23), which presented a cementocyte compatible gene expression signature, including the expression of dentin matrix protein 1 ( DMP1 ), sclerostin ( SOST ), and E11/gp38/podoplanin ( E11 ). In contrast, these cells did not express the odontoblast/dentin marker dentin sialoprotein ( DSPP ). HCY-23 cells produced mineral-like nodules in vitro under differentiation conditions, and were highly responsive to inorganic phosphate (Pi). Within the limits of the present study, it can be concluded that cementocytes are phosphate-responsive cells, and have the potential do play a key role in periodontal homeostasis and regeneration.

Mesenchymal stem cells in periodontics: new perspectives / Células mesenquimais indiferenciadas em periodontia: novas perspectivas

ABSTRACT Tissue engineering is a contemporary field of science, which aims to create conditions based on principles of cell and molecular biology, bioengineering and biomaterials to regenerate tissues. Mesenchymal stem cells present high proliferation rates and are able to differentiate into multilineages under certain conditions, suggesting that they have great potential to act in regeneration field. Tooth derived stem cells are a suitable alternative source of mesenchymal cells once they are easily accessible and have poor morbidity to the donor. Studies showed that they have been isolated and characterized from diverse tissues such as dental pulp, exfoliated deciduous teeth, periodontal ligament, gingiva, dental follicle and apical papilla. However studies show that there is heterogeneity among these populations and there is no standard method to select the most appropriate tooth derived stem cells for regenerative procedures. The aim of this review is to present the current perspective of the multiple types of tooth-derived stem cells and to discuss the basis for their use in periodontal tissue engineering.

RESUMO A engenharia de tecidos é um campo contemporâneo da ciência, que visa criar condições baseadas em princípios de biologia celular e molecular, bioengenharia e biomateriais para regenerar tecidos. As células tronco mesenquimais apresentam altas taxas de proliferação e são capazes de se diferenciar, sob certas condições, em multi-linhagens, sugerindo que elas têm grande potencial para atuar no campo da regeneração. As células tronco derivadas de tecidos dentais são uma fonte alternativa adequada de células mesenquimais uma vez que são de fácil acesso e têm baixa morbidade para o doador. Estudos demonstraram que elas já foram isoladas e caracterizadas a partir de diversos tecidos tais como polpa dentária, dentes decíduos esfoliados, ligamento periodontal, gengiva, folículo dental e papila apical. Entretanto, os estudos demonstram que há heterogeneidade entre essas populações e não existe um método padrão para selecionar as células-tronco dentais mais apropriadas para procedimentos regenerativos. O objetivo desta revisão é apresentar o conhecimento atual dos vários tipos de células-tronco derivadas de dentes e discutir as novas perspectivas para seu uso na engenharia de tecidos periodontais.

Osteogenic potential of periodontal ligament stem cells are unaffected after exposure to lipopolysaccharides

Abstract Periodontitis develops as a result of a continuous interaction between host cells and subgingival pathogenic bacteria. The periodontium has a limited capacity for regeneration, probably due to changes in periodontal ligament stem cells (PDLSCs) phenotype. The aim of this study was to evaluate the effects of lipopolysaccharides from Porphyromonas gingivalis (PgLPS) on mesenchymal phenotype and osteoblast/cementoblast (O/C) potential of PDLSCs. PDLSCs were assessed for Toll-like receptor 2 (TLR2) expression by immunostaining technique. After, cells were exposed to PgLPS, and the following assays were carried out: (i) cell metabolic activity using MTS; (ii) gene expression for IL-1β, TNF-α and OCT-4 by real-time polymerase chain reaction (RT-qPCR); (iii) flow cytometry for STRO-1 and CD105, and (iv) osteogenic differentiation. PDLSCs were positive for TLR2. PgLPS promoted cell proliferation, produced IL-1β and TNF-α, and did not affect the expression of stem cell markers, STRO-1, CD105 and OCT-4. Under osteogenic condition, PDLSCs exposed to PgLPS showed a similar potential to differentiate toward osteoblast/cementoblast phenotype compared to control group as revealed by mineralized matrix deposition and levels of transcripts for RUNX2, ALP and OCN. These results provide evidence that PgLPS induces pro-inflammatory cytokines, but does not change the mesenchymal phenotype and osteoblast/cementoblast differentiation potential of PDLSCs.

Biomimetic coatings enhance tribocorrosion behavior and cell responses of commercially pure titanium surfaces.

Biofunctionalized surfaces for implants are currently receiving much attention in the health care sector. Our aims were (1) to create bioactive Ti-coatings doped with Ca, P, Si, and Ag produced by microarc oxidation (MAO) to improve the surface properties of biomedical implants, (2) to investigate the TiO2 layer stability under wear and corrosion, and (3) to evaluate human mesenchymal stem cells (hMSCs) responses cultured on the modified surfaces. Tribocorrosion and cell experiments were performed following the MAO treatment. Samples were divided as a function of different Ca/P concentrations and treatment duration. Higher Ca concentration produced larger porous and harder coatings compared to the untreated group (p < 0.001), due to the presence of rutile structure. Free potentials experiments showed lower drops (-0.6 V) and higher coating lifetime during sliding for higher Ca concentration, whereas lower concentrations presented similar drops (-0.8 V) compared to an untreated group wherein the drop occurred immediately after the sliding started. MAO-treated surfaces improved the matrix formation and osteogenic gene expression levels of hMSCs. Higher Ca/P ratios and the addition of Ag nanoparticles into the oxide layer presented better surface properties, tribocorrosive behavior, and cell responses. MAO is a promising technique to enhance the biological, chemical, and mechanical properties of dental implant surfaces.

Coronally advanced flap with or without porcine collagen matrix for root coverage: a randomized clinical trial.

OBJECTIVES: The objective of this study is to clinically evaluate the outcomes following treatment of single gingival recessions with either coronally advanced flap technique (CAF) alone or combined with a porcine collagen matrix graft (CM). MATERIALS AND METHODS: This is a randomized parallel design clinical trial, including forty patients with single Miller Class I or II gingival recession, with a depth ≥ 2 mm and located at upper canines or premolars. The patients were randomly assigned to receive either CAF or CAF + CM. The primary outcome variable was gingival recession reduction (Rec Red). RESULTS: Baseline recession depth was 3.14 ± 0.51 mm for CAF group and 3.16 ± 0.65 mm for CAF + CM group (p > 0.05). Both groups showed significant Rec Red (p < 0.05), up to 6 months. Rec Red for CAF + CM was 2.41 ± 0.73 mm and was 2.25 ± 0.50 mm for CAF alone (p > 0.05). Root coverage was 77.2 % in the CAF + CM group and 72.1 % in the CAF group (p > 0.05). Complete root coverage (CRC) was found in 40 % of the cases in the CAF + CM group and in 35 % of the sites treated with CAF. Keratinized tissue thickness (KTT) was 0.26 mm higher in CAF + CM group (p < 0.05). CONCLUSIONS: It can be concluded that CAF + CM does not provide a superior recession reduction when compared to CAF; however, it may offer a small gain in KTT after 6 months. CLINICAL RELEVANCE: CAF + CM can be suggested as a valid therapeutic option to achieve root coverage and some increase in soft tissue thickness after 6 months.

Amoxicillin/metronidazole associated with nonsurgical therapy did not promote additional benefits in immunologic parameters in generalized aggressive periodontitis: A randomized controlled clinical trial.

OBJECTIVE: This randomized, blinded, placebo-controlled clinical trial compared the levels of interferon γ (IFN-γ), prostaglandin E2 (PGE2), and interleukin 6 (IL-6) in the gingival crevicular fluid (GCF) from generalized aggressive periodontitis (GAgP) patients treated with nonsurgical therapy associated or not with amoxicillin/metronidazole adjunctive. METHOD AND MATERIALS: Thirty-nine GAgP patients were followed during 6 months. The patients were randomly allocated to one of the groups: experimental (scaling and root planing plus 375 mg amoxicillin and 250 mg metronidazole for 7 days) and control (scaling and root planing + placebo). Probing pocket depth (PPD), relative clinical attachment level (rCAL), gingival margin position (GMP), and IL-6, IFN-γ, and PGE2 levels in GCF were evaluated at baseline, and at 3 and 6 months after treatment. RESULTS: Both therapies promoted PPD reductions, rCAL gains, and recession in GMP at the end of the study, with the experimental group presenting an additional PPD reduction in fullmouth analysis and deep pockets at the 3- and 6-month follow-ups (P < .05). During the period of the study, only the experimental group promoted a reduction in PGE2 levels in deep pockets at 3 and 6 months, while IFN-γ and IL-6 levels remained unchanged. However, the differences in the immunologic parameters were not statistically significant among the groups. CONCLUSION: It can be concluded that amoxicillin/ metronidazole associated with nonsurgical therapy promotes an additional PPD reduction in the treatment of GAgP; however, this therapy did not promote additional benefits in the evaluated immunologic parameters.

Engenharia tecidual em periodontia / Tissue engineering in Periodontics

Nas últimas décadas, muitos procedimentos foram realizados com o objetivo de regenerar o periodonto, como a regeneração tecidual guiada, a utilização de enxertos ósseos e os derivados da matriz do esmalte. No entanto, estudos têm demonstrado que estas terapias apresentam baixa previsibilidade de regenerar o periodonto. A fim de aumentar o potencial e previsibilidade de regeneração, a engenharia tecidual tem sido proposta como uma alternativa para promover as condições necessárias para regenerar os tecidos periodontais. Neste contexto, este trabalho teve como objetivo revisar a literatura acerca dos estudos de engenharia tecidual em Periodontia. A engenharia tecidual se baseia em princípios de biologia celular e engenharia de biomateriais, envolvendo basicamente três elementos-chave: células, moléculas de sinalização e arcabouços. O conjunto de células obtidas a partir do ligamento periodontal, assim como células isoladas com fenótipo de células mesenquimais indiferenciadas (células-tronco), tem sido investigado quanto ao potencial em promover a regeneração. Os efeitos das moléculas sinalizadoras sobre estas células e sobre o processo regenerativo também têm sido avaliados. Além disso, diversos arcabouços têm sido estudados com o objetivo de mimetizar a matriz extracelular, carrear células e liberar tais moléculas sinalizadoras na forma de proteínas recombinantes, a fim de propiciar um microambiente mais favorável à regeneração. Abordagens de engenharia tecidual envolvendo a interação destes três elementos têm demonstrado melhores resultados do que o uso isolado de um deles. Com base nestas abordagens, espera-se o desenvolvimento de técnicas que estimulem a regeneração periodontal, levando a resultados satisfatórios mais previsíveis.

Considerações clínicas para tratamento ortodôntico em paciente periodontal / Clinical considerations for orthodontic treatment in patients with periodontal disease: a review

A reabilitação oral do paciente muitas vezes necessita de uma inter-relação entre várias especialidades para permitir uma melhora nas condições da saúde bucal. Hoje, a procura cada vez maior de pacientes adultos para tratamento ortodôntico torna a Periodontia e a Ortodontia duas áreas com relação muito estreita no intuito de oferecer melhores resultados no tratamento odontológico do paciente. Sendo assim, o intuito desse trabalho foi realizar uma revisão da literatura sobre algumas questões relacionadas à inter-relação entre a Periodontia e a Ortodontia, principalmente no que diz respeito a: a) movimentação ortodôntica em pacientes com periodonto reduzido; b) movimentação ortodôntica e recessão gengival; c) microbiologia associada com bandas ortodônticas; d) aumento gengival relacionado à movimentação ortodôntica

Abordagem regenerativa combinada de proteínas derivadas da matriz do esmalte e substituto ósseo em defeito infraósseo de paciente com periodontite agressiva / Combined regenerative approach of derivative enamel proteins and bone substitute for treatment of infraosseous defect in aggressive periodontitis. Case report

Devido à rápida progressão da doença periodontal, a presença de defeitos periodontais infraósseos é um achado frequente nos pacientes portadores de periodontite agressiva. O objetivo deste trabalho foi relatar clínica e radiograficamente uma abordagem periodontal regenerativa em paciente com histórico de periodontite agressiva generalizada. A paciente apresentava persistência de bolsa periodontal associada a defeito infraósseo na mesial do dente 46 mesmo após abordagens periodontais não cirúrgicas. O sítio foi tratado por meio de terapia periodontal regenerativa utilizando-se proteínas derivadas da matriz do esmalte (PDME) associadas a substituto ósseo composto de beta-tricálcio-fosfato e hidroxiapatita (β-TCP-HA). Dez meses após a terapia regenerativa, observou-se redução da profundidade de sondagem e preenchimento radiográfico do defeito periodontal. Desta forma, pôde-se concluir que a terapia periodontal regenerativa foi capaz de promover melhoras clínicas, demonstrando que tal procedimento é viável, mesmo em pacientes com histórico de periodontite agressiva generalizada.

Considerações clínicas para tratamento ortodôntico em paciente periodontal / Clinical considerations for orthodontic treatment in patients with periodontal disease: a review

A reabilitação oral do paciente muitas vezes necessita de uma inter-relação entre várias especialidades para permitir uma melhora nas condições da saúde bucal. Hoje, a procura cada vez maior de pacientes adultos para tratamento ortodôntico torna a Periodontia e a Ortodontia duas áreas com relação muito estreita no intuito de oferecer melhores resultados no tratamento odontológico do paciente. Sendo assim, o intuito desse trabalho foi realizar uma revisão da literatura sobre algumas questões relacionadas à inter-relação entre a Periodontia e a Ortodontia, principalmente no que diz respeito a: a) movimentação ortodôntica em pacientes com periodonto reduzido; b) movimentação ortodôntica e recessão gengival; c) microbiologia associada com bandas ortodônticas; d) aumento gengival relacionado à movimentação ortodôntica.

Manutenção longitudinal do tratamento de peri-implantite / Long term clinical outcome of peri-implantitis treatment: a clinical report

O alto número de reabilitações orais com implantes, associadas à ausênciade uma correta terapia de manutenção, tem contribuído para o aparecimentode diversos casos de peri-implantite. Juntamente com este fato, odiagnóstico das doenças peri-implantares parece ser dificultado pelo desconhecimento,ou medo, dos cirurgiões-dentistas no exame das estruturasperi-implantares. O objetivo deste relato de caso clínico foi apresentaruma situação em que diagnóstico e tratamento da peri-implantite permitirama continuação e o sucesso da reabilitação oral com implantes. Dentrodas limitações do caso clínico apresentado concluiu-se que uma vez diagnosticadaa peri-implantite, a aplicação não cirúrgica de iodo povidine 10%,associado à abordagem cirúrgica, para a descontaminação da superfíciedos implantes e correção tecidual peri-implantar, por meio de enxerto detecido conjuntivo, e uma rigorosa terapia de suporte periodontal tornaramo resultado clínico satisfatório após 18 meses de acompanhamento, em setratando de estabilização do processo patológico.

Cigarette smoke inhalation influences bone healing of post-extraction tooth socket: a histometric study in rats.

The aim of this study was to evaluate, histometrically, the bone healing of the molar extraction socket just after cigarette smoke inhalation (CSI). Forty male Wistar rats were randomly assigned to a test group (animals exposed to CSI, starting 3 days before teeth extraction and maintained until sacrifice; n=20) and a control group (animals never exposed to CSI; n=20). Second mandibular molars were bilaterally extracted and the animals (n=5/group/period) were sacrificed at 3, 7, 10 and 14 days after surgery. Digital images were analyzed according to the following histometric parameters: osteoid tissue (OT), remaining area (RA), mineralized tissue (MT) and non-mineralized tissue (NMT) in the molar socket. Intergroup analysis showed no significant differences at day 3 (p>0.05) for all parameters. On the 7(th) day, CSI affected negatively (p<0.05) bone formation with respect to NMT and RA (MT: 36%, NMT: 53%, RA: 12%; and MT: 39%, NMT: 29%, RA: 32%, for the control and test groups, respectively). In contrast, no statistically significant differences (p>0.05) were found at days 10 and 14. It may be concluded that CSI may affect socket healing from the early events involved in the healing process, which may be critical for the amount and quality of new-bone formation in smokers.

Gingival recession associated with noncarious cervical lesions: combined periodontal-restorative approach and the treatment of long-term esthetic complications.

Buccal gingival recession is a prevalent problem in populations with a high standard of oral hygiene and is often associated with noncarious cervical lesions (NCCLs), leading to the need for a combined periodontal-restorative approach for better esthetic and functional results. In the literature, resin-modified glass ionomer (RMGI) restorations associated with periodontal surgery have been shown to achieve significant root coverage and reduction of dentin sensitivity; however, changes to the color of some of those restorations have been observed, which could compromise esthetics. Therefore, the aim of the present case report is to describe and discuss the current understanding of treatment for a gingival recession associated with an NCCL with a periodontal-restorative approach, and to describe treatment of RMGI color alteration problems two years after treatment.

A utilização do β tricálcio fosfato em associação com a matriz derivada do esmalte em defeito de bifurcação classe II / The use of Beta tricalicium phosphate in association with enamel matrix derivative in class II furcation defects

A presença do biofilme bacteriano é o principal fator etiológico envolvido na iniciação e no desenvolvimento das enfermidades que acometem a cavidade bucal. A remoção mecânica é um método capaz de controlar os patógenos periodontais. No entanto, muitos pacientes apresentam uma deficiência nos métodos de higiene diária habitual. Neste sentido, surgem agentes antimicrobianos capazes de agir de modo a auxiliar na prevenção e no tratamento destas doenças e diversos estudos na literatura têm mostrado a eficácia no emprego de tais substâncias antimicrobianas no controle do biofilme. Este artigo visou apresentar uma revisão da literatura sobre a utilização do agente antimicrobiano triclosan, possibilitando que os cirurgiões-dentistas conheçam melhor suas propriedades, seu mecanismo de ação e sua eficácia.

Cigarette smoke inhalation influences bone healing of post-extraction tooth socket: a histometric study in rats

The aim of this study was to evaluate, histometrically, the bone healing of the molar extraction socket just after cigarette smoke inhalation (CSI). Forty male Wistar rats were randomly assigned to a test group (animals exposed to CSI, starting 3 days before teeth extraction and maintained until sacrifice; n=20) and a control group (animals never exposed to CSI; n=20). Second mandibular molars were bilaterally extracted and the animals (n=5/group/period) were sacrificed at 3, 7, 10 and 14 days after surgery. Digital images were analyzed according to the following histometric parameters: osteoid tissue (OT), remaining area (RA), mineralized tissue (MT) and non-mineralized tissue (NMT) in the molar socket. Intergroup analysis showed no significant differences at day 3 (p>0.05) for all parameters. On the 7th day, CSI affected negatively (p<0.05) bone formation with respect to NMT and RA (MT: 36%, NMT: 53%, RA: 12%; and MT: 39%, NMT: 29%, RA: 32%, for the control and test groups, respectively). In contrast, no statistically significant differences (p>0.05) were found at days 10 and 14. It may be concluded that CSI may affect socket healing from the early events involved in the healing process, which may be critical for the amount and quality of new-bone formation in smokers.

O objetivo do estudo foi avaliar a influência da inalação da fumaça de cigarros (IFC) sobre os períodos iniciais de reparo ósseo alveolar. Quarenta ratos Wistar foram aleatoriamente divididos em teste: animais expostos à IFC, que se iniciou 3 dias antes das extrações mantendo-se até o sacrifício (n=20)e controle (animais que não foram expostos à IFC; n=20). Os animais tiveram seus segundos molares inferiores extraídos bilateralmente (n=5/grupo/período) e foram sacrificados nos dias 3, 7, 10 e 14 dias após a cirurgia. Imagens digitalizadas foram analisadas de acordo com os seguintes parâmetros histométricos: tecido osteóide (OT), área remanescente (RA), tecido mineralizado (MT) e tecido não mineralizado (NMT) em cada alvéolo. Análise intergrupo mostrou que não houve diferença estatisticamente significante aos 3 dias (p>0,05) para todos os parâmetros. Aos 7 dias, a IFC influenciou negativamente (p?0,05) o preenchimento ósseo mostrando diferença estatisticamente significante para os parâmetros tecido não mineralizado e defeito remanescente (MT: 36%, NMT: 53%, RA: 12%; and MT: 39%, NMT: 29%, RA: 32%, para controle e teste, respectivamente). No entanto, não houve diferença estatisticamente significante (p>0,05) aos 10 e 14 dias. Conclui-se que a IFC pode afetar o reparo ósseo alveolar inicial, o que pode ser crítico para a quantidade e qualidade da nova formação óssea em fumantes.