Fluoride-modified implant surfaces improves osseointegration in the tibias of rats with induced diabetes.

This study evaluated the influence of a fluoride-modified titanium surface on osseointegration in rats with induced diabetes. One hundred and eighty rats were randomly allocated into 3 groups with 60 animals each: Control group (C): Animals without diabetes; Diabetes Group (D): Animals with uncontrolled induced diabetes; Controlled Diabetes Group (CD): Animals with diabetes induced controlled by the insulin administration. Diabetes was induced by streptozotocin injection. Each animal received 2 implants in the proximal tibial metaphysis, one with the machined surface (M) and the other one with a fluoride-modified titanium surface (F), after 4 weeks of induction of diabetes. The animals were submitted to euthanasia 2, 4, and 6 weeks after the implant placement (n = 20 animals/group). The osseointegration was evaluated by the implant removal torque test and the histometric analysis of the non-decalcified histological sections: 1) Contact bone/implant (%BIC); 2) Bone tissue area between implant threads (%BBT). Implants with F surface showed a higher removal torque than implants with surface M in all groups. There was no difference in %BIC between the groups regardless of the surface used. The F surface showed a tendency to present higher %BBT values for the 3 evaluation periods in the D group. The fluoride-modified implant surface has no impact on the %BIC and %BBT. However, the fluoride-modified implant surface increases the locking of the implants with the bone. The hyperglycemia was associated with lower removal torque values despite the surfaces of the implant used.

Postoperative local interventions for the palate as a gingival graft donor area: a scoping review.

OBJECTIVE: This scoping review aimed to systematically identify evidence-based interventions to stimulate healing or protect the harvested palate of patients undergoing gingival grafting. MATERIAL AND METHODS: The study followed guidelines from the Joanna Briggs Institute and PRISMA-ScR (protocol available at osf.io/zhafn). PubMed, Embase, and seven other databases were searched on November 2022, with additional monitoring until April 2023. The inclusion criteria focused on studies evaluating outcomes related to the donor area (palate) and interventions for healing or protecting it, regardless of publication year and language. Data from the included publications was extracted and presented through narrative text, tables, and figures. RESULTS: Eighty-one studies (including 64 clinical trials, four case series, five theses, and eight systematic reviews) and 37 clinical trial records were included. The number of studies on this topic has significantly increased, reflecting a growing interest in the field. Thirty-six interventions with published results and 12 interventions with unpublished results from clinical trial registers were identified. Some promising interventions that showed potential for improving patient-reported outcomes include cyanoacrylate adhesive, platelet-rich fibrin (PRF), and the combination of palatal stents and healing agents. CONCLUSIONS: Thirty-six interventions with published results were identified for postoperative use on the harvested palate, showing varying levels of evidence and conflicting effectiveness for specific outcomes. CLINICAL RELEVANCE: Postoperative discomfort and pain in the palate are commonly experienced by patients undergoing grafting procedures using this region as the donor area. Awareness of the available options and their levels of evidence is crucial for informed decision-making.

Fluoride-modified implant surfaces improves osseointegration in the tibias of rats with induced diabetes

Abstract This study evaluated the influence of a fluoride-modified titanium surface on osseointegration in rats with induced diabetes. One hundred and eighty rats were randomly allocated into 3 groups with 60 animals each: Control group (C): Animals without diabetes; Diabetes Group (D): Animals with uncontrolled induced diabetes; Controlled Diabetes Group (CD): Animals with diabetes induced controlled by the insulin administration. Diabetes was induced by streptozotocin injection. Each animal received 2 implants in the proximal tibial metaphysis, one with the machined surface (M) and the other one with a fluoride-modified titanium surface (F), after 4 weeks of induction of diabetes. The animals were submitted to euthanasia 2, 4, and 6 weeks after the implant placement (n = 20 animals/group). The osseointegration was evaluated by the implant removal torque test and the histometric analysis of the non-decalcified histological sections: 1) Contact bone/implant (%BIC); 2) Bone tissue area between implant threads (%BBT). Implants with F surface showed a higher removal torque than implants with surface M in all groups. There was no difference in %BIC between the groups regardless of the surface used. The F surface showed a tendency to present higher %BBT values for the 3 evaluation periods in the D group. The fluoride-modified implant surface has no impact on the %BIC and %BBT. However, the fluoride-modified implant surface increases the locking of the implants with the bone. The hyperglycemia was associated with lower removal torque values despite the surfaces of the implant used.

Resumo Este estudo avaliou a influência de uma superfície de titânio modificada com flúor na osseointegração em ratos com diabetes induzida. Cento e oitenta ratos foram distribuídos aleatoriamente em 3 grupos com 60 animais cada: Grupo controle (C): Animais sem diabetes; Grupo Diabetes (D): Animais com diabetes induzida descompensada; Grupo Diabetes Controlado (CD): Animais com diabetes induzido controlado pela administração de insulina. O diabetes foi induzido por injeção de estreptozotocina. Cada animal recebeu 2 implantes na metáfise proximal da tíbia, um com superfície usinada (M) e outro com superfície de titânio modificado com flúor (F), após 4 semanas de indução do diabetes. Os animais foram submetidos à eutanásia 2, 4 e 6 semanas após a colocação do implante (n = 20 animais/grupo). A osseointegração foi avaliada pelo teste de torque de remoção do implante e pela análise histométrica dos cortes histológicos não descalcificados: 1) Contato osso-implante (%BIC); 2) Área de tecido ósseo entre as roscas do implante (%BBT). Os implantes com superfície F apresentaram maior torque de remoção do que os implantes com superfície M em todos os grupos. Não houve diferença no %BIC entre os grupos independente da superfície utilizada. A superfície F mostrou tendência a apresentar maiores valores de %BBT para os 3 períodos de avaliação no grupo D. As superfícies de implantes modificadas com flúor não influenciaram nos dados de %BIC e %BBT. Entretanto, essas superfícies aumentaram o travamento dos implantes no tecido ósseo. A hiperglicemia foi associada a menores torques de remoção dos implantes independentemente do tipo de superfície de implante utilizada.

Laser-Modified Ti Surface Improves Paracrine Osteogenesis by Modulating the Expression of DKK1 in Osteoblasts.

Titanium surface modifications are widely used to modulate cellular behavior by recognition of topographical cues. However, how those modifications affect the expression of mediators that will influence neighboring cells is still elusive. This study aimed to evaluate the effects of conditioned media from osteoblasts cultured on laser-modified titanium surfaces on the differentiation of bone marrow cells in a paracrine manner and to analyze the expression of Wnt pathway inhibitors. Mice calvarial osteoblasts were seeded on polished (P) and Yb:YAG laser-irradiated (L) Ti surfaces. Osteoblast culture media were collected and filtered on alternate days to stimulate mice BMCs. Resazurin assay was performed every other day for 20 days to check BMC viability and proliferation. After 7 and 14 days of BMCs maintained with osteoblasts P and L-conditioned media, alkaline phosphatase activity, Alizarin Red staining, and RT-qPCR were performed. ELISA of conditioned media was conducted to investigate the expression of Wnt inhibitors Dickkopf-1 (DKK1) and Sclerostin (SOST). BMCs showed increased mineralized nodule formation and alkaline phosphatase activity. The L-conditioned media enhanced the BMC mRNA expression of bone-related markers Bglap, Alpl, and Sp7. L-conditioned media decreased the expression of DKK1 compared with P-conditioned media. The contact of osteoblasts with Yb:YAG laser-modified Ti surfaces induces the regulation of the expression of mediators that affect the osteoblastic differentiation of neighboring cells. DKK1 is among these regulated mediators.

Effects of Curcuma as an adjunct therapy on periodontal disease: A systematic review and meta-analysis.

BACKGROUND: Periodontal disease (PD) is the second most prevalent buccal infectious condition in adults. Owing to its multifactorial etiology, treatment and maintenance are challenging. Scaling and root planing, associated with adequate plaque control, are considered the gold standard treatments for this disease. However, the instrumentation techniques can fail to completely eliminate calculus, particularly in higher grade and progression rated PD cases, and the continuing efficient removal of the biofilm by the patient can limit the long-term response of this treatment. Anti-infective herbal products, such as Curcuma, have been added as adjuvant therapy to prolong periodontal treatment outcomes. OBJECTIVE: This systematic review aimed to summarize and evaluate whether Curcuma can contribute to PD treatment when applied as an adjunct to the standard scaling and root planing therapy. DATA SOURCES: We searched databases using specific keywords and Boolean operators and systematically conducted the extraction and analysis according to the PROSPERO (CRD42019145691) database. The main eligibility criteria were randomized clinical trials in humans published in the English language. RESULTS: Twelve studies were included in the review and 11 in the meta-analysis. Quantitative analysis of different clinical parameters was described. In comparison with the control group, Curcuma was associated with a reduction in pocket depth after 90 days of treatment (mean deviation: 0.48; 95% confidence interval: 0.89-0.08). CONCLUSION: This systematic review and meta-analysis indicated that Curcuma is an effective product when applied as adjunct therapy for PD treatment. This improved the clinical and microbiological parameters.

Postsurgical oral symptoms after insertion of one or two implants for mandibular overdentures: short-term results of a randomized clinical trial.

OBJECTIVE: This randomized clinical trial aimed to compare the short-term postsurgical symptoms after insertion of one or two implants for retention of a mandibular overdenture. This study investigated whether the less invasive single-implant approach results in lower postoperative symptoms compared to the conventional two-implant overdenture. MATERIALS AND METHODS: Patients received new complete dentures and were randomly assigned to groups receiving one or two single-stage, early-loaded hydrophilic implants, inserted in the midline (n = 23), or the lateral incisor-canine area bilaterally (n = 24). Patient-reported postoperative symptoms were measured in a 0-100 visual analogue scale concerning pain in the surgical area, pain when chewing, bleeding, swelling, and unpleasantness. Data collection occurred 24 h and 7 and 21 days after surgery. Demographic and clinical features (smoking habit, classification of the residual ridges, and mucosal width and thickness at the implant sites), osteotomy for alveolar bone reduction, and surgery time were tested as predictors of symptom levels. RESULTS: Overall reported symptoms were mild and self-limited, with high rates of complete remission after the early loading period of 3 weeks. Progressive improvement of symptoms occurred from the 24-h to the 7-day and 21-day follow-ups (p < 0.001), similarly in both groups. None of the clinical predictors was significantly associated with the changes in symptoms. CONCLUSIONS: Findings suggest that the insertion of one or two implants may result in similar postoperative outcomes. CLINICAL RELEVANCE: The severity of short-term postoperative symptoms may not be a critical factor for the decision between overdenture treatment with one or two implants.

Single versus two-implant mandibular overdentures using early-loaded titanium-zirconium implants with hydrophilic surface and ball attachments: 1-year randomized clinical trial.

OBJECTIVE: This randomized clinical trial aimed to compare the outcomes of the mandibular overdenture retained by one (1-IOD) or two (2-IOD) implants. MATERIALS AND METHODS: Participants received new complete dentures, were assessed at baseline and randomly assigned to groups. Early loaded single midline implant (1-IOD) or two implants in the canine regions bilaterally (2-IOD). Ball attachments were used for overdenture retention. Post-treatment outcomes (6- and 12-month follow-ups) included patient satisfaction, oral health-related quality of life measures, and chewing function. Data analysis included within- and between-group comparisons, and Generalized Estimating Equations. Both superiority and non-inferiority hypotheses were tested. RESULTS: Forty-seven participants were included (1-IOD = 23; 2-IOD = 24). Significant improvements in OHIP-Edent were observed after insertion of new dentures and at the 1-year follow-up compared with baseline. No differences were found between the 1- and 2-IOD groups for the OHIP-Edent and QoLFAST scores. Patient satisfaction with the mandibular denture improved significantly from baseline to the 6-month follow-up and remained unaltered until 1 year, with no differences between groups. The magnitudes of treatment effect sizes were moderate to large for patient-reported outcomes. Progressive improvement in chewing function occurred in both groups. Non-inferiority testing based on a 15% non-inferiority margin showed inconclusive results for patient-reported outcomes, whilst chewing function in the 1-IOD group was concluded to be not inferior to the 2-IOD group. CONCLUSIONS: Results support the use of both 1- and 2-IOD. The 1-IOD was also an acceptable alternative to the 2-IOD as a secondary option for the treatment of the edentulous mandible.

Pam2CSK4 (TLR2 agonist) induces periodontal destruction in mice.

Lipoproteins are important bacterial immunostimulating molecules capable of inducing receptor activator of nuclear factor-κB (RANKL) and osteoclast formation in vitro and in vivo . Although these molecules are present in periodontopathogenic bacteria, their role in periodontitis is not known. In this study, we used Pam2CSK4 (PAM2), a synthetic molecule that mimics bacterial lipoprotein, to investigate the effects of lipoproteins on periodontitis in mice. C57BL/6 male mice were randomly divided into three experimental groups: 1) Negative control group: animals received vehicle injection; 2) Positive control group: animals received injection of Escherichia coli lipopolysaccharide (LPS); 3) PAM2 group: animals received PAM2 injection. All the injections were performed bilaterally every other day into the palatal mucosa between first and second molars. After twenty-four days, the animals were euthanized to assess alveolar bone volume (micro-CT), cellular and extracellular composition in the gingiva (stereometric analysis), and osteoclast numbers (TRAP staining). Treatment with either PAM2 or LPS induced gingival inflammation, as demonstrated by increased infiltration of inflammatory cells and enhanced angiogenesis, associated with a smaller number of fibroblasts and decreased extracellular matrix. Importantly, treatment not only with LPS but also with PAM2 resulted in a larger number of TRAP+ multinucleated osteoclasts and significant loss of alveolar bone. Collectively, our data demonstrate that PAM2 can induce gingival inflammation and bone loss in mice, broadening the avenues of investigation into the role of lipoproteins in the pathogenesis of periodontal disease.

Patient satisfaction with ball and Equator attachments for single-implant mandibular overdentures: A short-term randomised crossover clinical trial.

BACKGROUND: Retention and stabilisation of a single-implant mandibular overdenture (SIMO) are influenced by the biomechanical properties and clinical performance of the attachment system. PURPOSE: To compare clinical and patient-reported outcomes following the use of two retention systems, a ball and a stud-type Equator attachment used for SIMO. MATERIAL AND METHODS: Eighteen fully edentulous participants were treated with a SIMO opposing to a maxillary complete denture. They received two retentive attachments (ball and Equator) in alternate periods (sequences A-B and B-A) and outcomes were assessed after the 1 week (initial) and 3 months (final) periods. In the final assessment, patients were also asked about their preferred retention system. RESULTS: Compared with baseline, there was an improvement in patient satisfaction using both attachments, whilst no difference was observed between initial and final periods. Similarly, no significant differences were observed when comparing the ball and Equator at the initial (P = .330) and final (P = .08) periods. The multilevel mixed-model analysis revealed that the patients' satisfaction was predicted only by their satisfaction with dentures before implant placement. Although no significant difference was found between attachments regarding patient preference, this may be biased by the sequence of attachment use, which suggests that a learning effect might be present in this crossover study design. CONCLUSION: The use of a single midline implant to retain a mandibular overdenture significantly improves patient satisfaction irrespective of the attachment used, but patients' preference for the second treatment suggested a learning effect in this study.

Pam2CSK4 (TLR2 agonist) induces periodontal destruction in mice

Abstract Lipoproteins are important bacterial immunostimulating molecules capable of inducing receptor activator of nuclear factor-κB (RANKL) and osteoclast formation in vitro and in vivo . Although these molecules are present in periodontopathogenic bacteria, their role in periodontitis is not known. In this study, we used Pam2CSK4 (PAM2), a synthetic molecule that mimics bacterial lipoprotein, to investigate the effects of lipoproteins on periodontitis in mice. C57BL/6 male mice were randomly divided into three experimental groups: 1) Negative control group: animals received vehicle injection; 2) Positive control group: animals received injection of Escherichia coli lipopolysaccharide (LPS); 3) PAM2 group: animals received PAM2 injection. All the injections were performed bilaterally every other day into the palatal mucosa between first and second molars. After twenty-four days, the animals were euthanized to assess alveolar bone volume (micro-CT), cellular and extracellular composition in the gingiva (stereometric analysis), and osteoclast numbers (TRAP staining). Treatment with either PAM2 or LPS induced gingival inflammation, as demonstrated by increased infiltration of inflammatory cells and enhanced angiogenesis, associated with a smaller number of fibroblasts and decreased extracellular matrix. Importantly, treatment not only with LPS but also with PAM2 resulted in a larger number of TRAP+ multinucleated osteoclasts and significant loss of alveolar bone. Collectively, our data demonstrate that PAM2 can induce gingival inflammation and bone loss in mice, broadening the avenues of investigation into the role of lipoproteins in the pathogenesis of periodontal disease.

Reabilitação com Instalação de Implante Imediato em Região de Molar com Abordagem Alternativa de Osteotomia: Relato de Caso / Rehabilitation With Immediate Implant Placement in Molar Region Using an Alternative Osteotomy Approach: a Case Report

Objetivo: apresentar um caso clínico de instalação de implante imediato em região de bifurcação após exodontia de molar com uma técnica de osteotomia alternativa com o preparo do sitio implantar previamente à remoção das raízes. Materiais e métodos: em dezembro de 2017, JNPS, 39 anos de idade, sexo masculino, compareceu à Faculdade de Odontologia com queixa do dente 46 fraturado sem sintomatologia dolorosa. Nos exames clínicos e radiográficos o dente 46 apresentava tratamento endodôntico, sem remanescente coronário e amplo septo inter-radicular que favorecia a instalação de implante imediato. A cirurgia ocorreu em fevereiro de 2018 com o preparo do leito do implante na região do centro do dente previamente à exodontia. Em seguida foi realizada a extração das raízes de forma minimamente traumática, visando preservar a estrutura circundante. Foi utilizado um implante Cone Morse 3,75x9mm (Titamax CM Cortical ­ Neodent, Curitiba, Brasil). O torque final de inserção foi de 20 N/cm e foi instalado o cicatrizador para procedimento cirúrgico de 1 estágio. Após 4 meses foi instalado o pilar protético (Pilar CM ­ Neodent, Curitiba, Brasil) com altura de 2,5 mm e nas sessões seguintes foram realizados os procedimentos para confecção de coroa metalocerâmica. Resultados: no acompanhamento de 12 meses após instalação do implante, verificou-se aspectos clínicos e radiográficos de normalidade, além de satisfação do paciente com o tratamento. Conclusão: a técnica utilizada facilita o preparo do leito receptor e a instalação de implante em condições de estabilidade favorável, podendo ser empregada em situações clínicas semelhantes.

Objective: to present a case report of immediate implant surgery in the region of an extensively damaged molar using an alternative osteotomy technique with bone drilling prior to root extraction. Materials and methods: in December 2017 JNPS, 39-years-old male patient, attended to the Faculty of Dentistry, complaining about a fractured tooth without pain symptoms. At clinical and radiographic exams, tooth #46 was endodontically treated without coronal structure and wide inter-radicular septum, favoring the insertion of an immediate implant. Implant surgery was performed in February 2018 by drilling the implant bone site in the central region of the tooth prior to extraction. Then, the roots were extracted using minimally traumatic procedures, aiming to preserve the surrounding bone structure. A 3.75x9 mm morse taper implant (Titamax CM Cortical, Neodent, Curitiba, Brazil) was inserted. The final insertion torque was 20 N/cm was obtained and a healing cap was installed for a onestage surgical procedure. After 4 months, a 2.5mm height prosthetic abutment (Pilar CM - Neodent, Curitiba, Brazil) was installed and in the following appointments the procedures for fabrication of a metalceramic crown were performed. Results: in the 12-month follow-up, clinical and radiographic aspects of normality were observed, and patient reported satisfaction with the treatment. Conclusion: the technique used in this clinical case facilitated the bone preparation for implant insertion, preserving bone structure for a favorable implant stability, and may be recommended for similar clinical situations.

Topical application of bFGF on acid-conditioned and non-conditioned dentin: effect on cell proliferation and gene expression in cells relevant for periodontal regeneration.

MATERIAL AND METHODS: Periodontal regeneration is still a challenge in terms of predictability and magnitude of effect. In this study we assess the biological effects of combining chemical root conditioning and biological mediators on three relevant cell types for periodontal regeneration. Bovine dentin slices were conditioned with 25% citric acid followed by topical application of basic fibroblast growth factor (bFGF, 10 and 50 ng). We used ELISA to assess the dynamics of bFGF release from the dentin surface and RT-qPCR to study the expression of Runx2, Col1a1, Bglap and fibronectin by periodontal ligament (PDL) fibroblasts, cementoblasts and bone marrow stromal cells (BMSC) grown onto these dentin slices. We also assessed the effects of topical application of bFGF on cell proliferation by quantification of genomic DNA. RESULTS: Acid conditioning significantly increased the release of bFGF from dentin slices. Overall, bFGF application significantly (p<0.05) increased cell proliferation, except for BMSC grown on non-conditioned dentin slices. Dentin substrate discretely increased expression of Col1a1 in all cell types. Expression of Runx2, Col1a1 and Fn was either unaffected or inhibited by bFGF application in all cell types. We could not detect expression of the target genes on BMSC grown onto conditioned dentin. CONCLUSION: Acid conditioning of dentin improves the release of topically-applied bFGF. Topical application of bFGF had a stimulatory effect on proliferation of PDL fibroblasts, cementoblasts and BMSC, but did not affect expression of Runx2, Col1a1, Bglap and fibronectin by these cells.

Topical application of bFGF on acid-conditioned and non-conditioned dentin: effect on cell proliferation and gene expression in cells relevant for periodontal regeneration

Abstract Periodontal regeneration is still a challenge in terms of predictability and magnitude of effect. In this study we assess the biological effects of combining chemical root conditioning and biological mediators on three relevant cell types for periodontal regeneration. Material and Methods: Bovine dentin slices were conditioned with 25% citric acid followed by topical application of basic fibroblast growth factor (bFGF, 10 and 50 ng). We used ELISA to assess the dynamics of bFGF release from the dentin surface and RT-qPCR to study the expression of Runx2, Col1a1, Bglap and fibronectin by periodontal ligament (PDL) fibroblasts, cementoblasts and bone marrow stromal cells (BMSC) grown onto these dentin slices. We also assessed the effects of topical application of bFGF on cell proliferation by quantification of genomic DNA. Results: Acid conditioning significantly increased the release of bFGF from dentin slices. Overall, bFGF application significantly (p<0.05) increased cell proliferation, except for BMSC grown on non-conditioned dentin slices. Dentin substrate discretely increased expression of Col1a1 in all cell types. Expression of Runx2, Col1a1 and Fn was either unaffected or inhibited by bFGF application in all cell types. We could not detect expression of the target genes on BMSC grown onto conditioned dentin. Conclusion: Acid conditioning of dentin improves the release of topically-applied bFGF. Topical application of bFGF had a stimulatory effect on proliferation of PDL fibroblasts, cementoblasts and BMSC, but did not affect expression of Runx2, Col1a1, Bglap and fibronectin by these cells.

Suppressor of cytokine signaling 1 expression during LPS-induced inflammation and bone loss in rats.

This study aimed to characterize the dynamics of suppressor of cytokine signaling (SOCS1) expression in a rat model of lipopolysaccharide-induced periodontitis. Wistar rats in the experimental groups were injected three times/week with LPS from Escherichia coli on the palatal aspect of the first molars, and control animals were injected with vehicle (phosphate-buffered saline). Animals were sacrificed 7, 15, and 30 days after the first injection to analyze inflammation (stereometric analysis), bone loss (macroscopic analysis), gene expression (qRT-PCR), and protein expression/activation (Western blotting). The severity of inflammation and bone loss associated with LPS-induced periodontitis increased from day 7 to day 15, and it was sustained through day 30. Significant (p < 0.05) increases in SOCS1, RANKL, OPG, and IFN-γ gene expression were observed in the experimental group versus the control group at day 15. SOCS1 protein expression and STAT1 and NF-κB activation were increased throughout the 30-day experimental period. Gingival tissues affected by experimental periodontitis express SOCS1, indicating that this protein may potentially downregulate signaling events involved in inflammatory reactions and bone loss and thus may play a relevant role in the development and progression of periodontal disease.

Effects of avocado/soybean unsaponifiables (ASU) on the treatment of ligature-induced periodontitis in rats

The purpose of this study is to evaluate the effect of the avocado/soybean unsaponifiables (ASU) on the treatment of induced periodontitis in rats. Periodontitis was induced in 84 rats via ligature placement around the second upper molar, which was removed after 7 days, and scaling and root planning (SRP) was performed at this time. Subsequently, the rats were randomly allocated to four groups with 21 animals each: One SRP group in which saline solution was administered (SS), and three groups in which ASU was administered (0.6 g/kg/day), beginning either 7 days before the induction of periodontitis (SRP/ASU-7), on the day of periodontitis induction (SRP/ASU0), or on the day of treatment (SRP/ASU+7). ASU and SS were administered daily by gavage until the sacrifice of the animals (7, 15, and 30 days after SRP). The % bone in the furcation area was evaluated by histomorphometry and micro-CT. The expression of proteins (TRAP, RANKL, and alkaline phosphatase) and mRNA (IL-1ß, TNF-α, IL-6, RANKL, and alkaline phosphatase) were evaluated by immunohistochemistry and qPCR. The SRP/ASU+7 group presented a higher percentage of bone fill in the furcation area and higher expression of alkaline phosphatase than in the SRP group (at 7 and 30 days, respectively). The SRP/ASU0 and SRP/ASU+7 groups presented lower expression levels of RANKL mRNA than the SRP and SRP/ASU-7 groups at 15 days. ASU administration on the day of the SRP treatment of the ligature-induced periodontitis promoted subtle beneficial effects on periodontal repair following the treatment of induced periodontitis within the experimental period of 7 days.

Suppressor of cytokine signaling 1 expression during LPS-induced inflammation and bone loss in rats

Abstract This study aimed to characterize the dynamics of suppressor of cytokine signaling (SOCS1) expression in a rat model of lipopolysaccharide-induced periodontitis. Wistar rats in the experimental groups were injected three times/week with LPS from Escherichia coli on the palatal aspect of the first molars, and control animals were injected with vehicle (phosphate-buffered saline). Animals were sacrificed 7, 15, and 30 days after the first injection to analyze inflammation (stereometric analysis), bone loss (macroscopic analysis), gene expression (qRT-PCR), and protein expression/activation (Western blotting). The severity of inflammation and bone loss associated with LPS-induced periodontitis increased from day 7 to day 15, and it was sustained through day 30. Significant (p < 0.05) increases in SOCS1, RANKL, OPG, and IFN-γ gene expression were observed in the experimental group versus the control group at day 15. SOCS1 protein expression and STAT1 and NF-κB activation were increased throughout the 30-day experimental period. Gingival tissues affected by experimental periodontitis express SOCS1, indicating that this protein may potentially downregulate signaling events involved in inflammatory reactions and bone loss and thus may play a relevant role in the development and progression of periodontal disease.

Effects of avocado/soybean unsaponifiables (ASU) on the treatment of ligature-induced periodontitis in rats

Abstract The purpose of this study is to evaluate the effect of the avocado/soybean unsaponifiables (ASU) on the treatment of induced periodontitis in rats. Periodontitis was induced in 84 rats via ligature placement around the second upper molar, which was removed after 7 days, and scaling and root planning (SRP) was performed at this time. Subsequently, the rats were randomly allocated to four groups with 21 animals each: One SRP group in which saline solution was administered (SS), and three groups in which ASU was administered (0.6 g/kg/day), beginning either 7 days before the induction of periodontitis (SRP/ASU-7), on the day of periodontitis induction (SRP/ASU0), or on the day of treatment (SRP/ASU+7). ASU and SS were administered daily by gavage until the sacrifice of the animals (7, 15, and 30 days after SRP). The % bone in the furcation area was evaluated by histomorphometry and micro-CT. The expression of proteins (TRAP, RANKL, and alkaline phosphatase) and mRNA (IL-1β, TNF-α, IL-6, RANKL, and alkaline phosphatase) were evaluated by immunohistochemistry and qPCR. The SRP/ASU+7 group presented a higher percentage of bone fill in the furcation area and higher expression of alkaline phosphatase than in the SRP group (at 7 and 30 days, respectively). The SRP/ASU0 and SRP/ASU+7 groups presented lower expression levels of RANKL mRNA than the SRP and SRP/ASU-7 groups at 15 days. ASU administration on the day of the SRP treatment of the ligature-induced periodontitis promoted subtle beneficial effects on periodontal repair following the treatment of induced periodontitis within the experimental period of 7 days.

Immune-Inflammatory Cell Profile and Receptor Activator of Nuclear Factor Kappa B Ligand/Osteoprotegerin Expression in Persistent Apical Periodontitis after Root Canal Retreatment Failure.

INTRODUCTION: This study assessed the immune-inflammatory profile and the expression of bone resorption activators receptor activator of nuclear factor kappa B ligand (RANKL) and inhibitor osteoprotegerin (OPG) in apical periodontitis (n = 20) that persisted after root canal retreatment. METHODS: Immunohistochemistry was used to characterize lymphocyte populations (CD3+, CD45RO+, CD8+, and FoxP3+ cells), macrophages (CD68+), RANKL+ and OPG+ cells in persistent apical periodontitis (PAP) and primary periapical lesions (PPLs). By using quantitative real-time polymerase chain reaction, the mRNA expression of RANKL and OPG in PAP and periodontal ligament from healthy teeth was comparatively analyzed. The data were analyzed by Mann-Whitney, Pearson χ2, and Wilcoxon tests (5% level). RESULTS: PAP showed an elevated number of FoxP3+ cells compared with PPL (P < .001). The number of CD68+ cells was reduced in the PAP samples compared with the PPLs (P < .001). Similar number of other lymphocyte populations was observed in PAP and PPLs (P > .05 for all comparisons). No differences in the RANKL, OPG, and immune-inflammatory cells were demonstrated when comparing PAP microscopically classified as cyst with those classified as granulomas (P > .05 for all comparisons). The assessment of mRNA expression revealed higher levels of RANKL and OPG in PAP compared with the periodontal ligament from healthy teeth (control) samples (P < .001). Also, a greater expression of RANKL in comparison with OPG was observed in PAP (P < .001). CONCLUSIONS: These findings indicate that PAP consists of biologically active lesions that demonstrate potential of bone resorption (higher expression of RANKL) and is characterized by an immune-inflammatory cell profile that suggests a suppressive and regulatory environment (higher number of FoxP3+ cells and lower number of macrophages) favorable to more chronic clinical behavior.