Cytokine levels in the gingival crevicular fluid and their association with periodontal status of down syndrome patients: a cross-sectional study.

OBJECTIVE: To evaluate cytokine levels of interleukin (IL)-1ß, IL-4, IL-6, IL-17a, tumor necrosis factor (TNF)-α, and interferon (IFN)-γ in the gingival crevicular fluid (GCF) of periodontal sites in individuals with Down syndrome (DS) and analyze their relationship with clinical periodontal parameters. MATERIALS AND METHODS: A cross-sectional study was conducted with 49 DS patients and 32 individuals without DS (non-DS group). Periodontal probing depth (PPD), clinical attachment level (CAL), bleeding on probing (BoP), and visible plaque index (VPI) were evaluated. The periodontal sites were classified as shallow, moderate, and deep. GCF was collected in all shallow sites and, when present, in moderate and deep sites for the analysis of cytokine levels. The cytokines, IL-1ß, IL-4, IL-6, IL-17a, TNF-α, and IFN-γ, were quantified using the Luminex® automatic analyzer system. RESULTS: The DS group presented greater severity of periodontitis compared to the non-DS group (P = 0.005). The DS group showed a significant direct correlation of IL-1ß and an inverse correlation of IFN-γ and IL-14 with all periodontal variables. In the analysis stratified by periodontal pocket depth, we observed a higher level of IFN-γ, IL-17a, IL-1ß, and IL-6 in the shallow sites, and IL-17a, IL-1ß, and IL-6 in deep pockets of DS group individuals. Multivariate models showed that higher levels of IL-1ß, IL-4, IL-6, and IL-17a were associated with Down syndrome even after adjusting for periodontal status, sex, and age. CONCLUSION: The findings suggest that people with DS have greater periodontal impairment and higher levels of cytokines in GCF, even in sites having clinical periodontal parameters similar to those of individuals without DS. These data reiterate the concept of an altered and less effective immune response in the population with DS in the face of a periodontal microbial challenge. CLINICAL RELEVANCE: Elevated periodontal inflammation burden can be observed with higher cytokine levels in the gingival crevicular fluid of people with Down syndrome, especially IL-1, IL-4, IL-6, and IL-17, regardless of the stage of periodontitis.

Identifying metabolic parameters related to severity and extent of periodontitis in down syndrome patients.

BACKGROUND AND OBJECTIVE: Systemic metabolic status and periodontitis can be related in patients with Down syndrome (DS). The objective of this study was to identify metabolic indicators (anthropometric measurements, blood pressure, and serum markers) related to severity and extent of periodontitis in DS patients. METHODS: A cross-sectional study was conducted with 49 patients with DS. Periodontal evaluation included the periodontal probing depth (PPD), clinical attachment level (CAL), gingival bleeding index (GBI), and visible plaque index (VPI). Periodontitis severity was classified by the stages system. The extent of periodontitis was assessed as the percentage of sites with CAL ≥3 mm, CAL ≥4 mm, PPD ≥4 mm, and PPD ≥5 mm. The metabolic condition of the participants was determined by analyzing anthropometric parameters, blood pressure, and serum markers. Data were analyzed using the Mann-Whitney test, Spearman's correlation coefficient, and multivariate regression analysis. RESULTS: Periodontitis stage 3/4 was detected in 32.7% of patients, with high values of VPI (54.6 ± 35.8) and GBI (42.4 ± 33.3). The severity of periodontitis was related to higher mean corpuscular hemoglobin (ß = .291, p = .028) and mean corpuscular volume values (ß = .293, p = .046). Arm circumference measurements were inversely related to CAL ≥3 mm (ß = -.408, p = .023), PPD ≥4 mm (ß = -.475, p = .006), and PPD ≥5 mm (ß = -.443, p = .010). CONCLUSIONS: The findings suggest that the severity and extent of periodontitis may be related to some metabolic parameters in DS patients.

Systemic circulating inflammatory burden and periodontitis in adolescents.

OBJECTIVES: To analyze the association between systemic inflammatory burden of cardiovascular disease (CVD) risk and periodontitis in adolescents, including mediating pathways triggered by their common risk factors. MATERIALS AND METHODS: Using a population-based sample study (n = 405) of Brazilian adolescents (17-18 years old), direct and mediation pathways triggered by "Socioeconomic Status," "Adiposity," Smoking, and "Blood Pressure" were modelled for the association between the "Systemic Circulating Inflammatory Burden of CVD Risk" (IL-1ß, IL-6, IL-8, TNF-α) and the "Initial Periodontitis" (bleeding on probing (BoP), probing depth (PD) ≥ 4 mm, clinical attachment loss (CAL) ≥ 4 mm), both as continuous latent variables, using structural equation modeling. Sensitivity analysis was performed for the outcomes "Gingivitis" (visible plaque; BoP); "Moderate Periodontitis" (PD ≥ 5 mm and CAL ≥ 5 mm) and periodontitis (CDC-AAP case definition). RESULTS: Higher "Systemic Circulating Inflammatory Burden of CVD Risk" was directly associated with higher "Initial Periodontitis" (standardized coefficient [SC] = 0.178, P value < 0.001). Lower "Socioeconomic Status" (SC = - 0.022, P value = 0.015) and Smoking (SC = 0.030, P value = 0.021) triggered the "Initial Periodontitis", mediated by "Systemic Circulating Inflammatory Burden of CVD Risk". Sensitivity analysis showed a dose-response relationship between "Systemic Circulating Inflammatory Burden of CVD Risk" and "Moderate Periodontitis" (SC = 0.323, P value = 0.021). CONCLUSIONS: "Systemic Circulating Inflammatory Burden of CVD Risk" appeared as an underlying mechanism of early periodontal breakdown in adolescents, also triggered by social vulnerability and smoking. CLINICAL RELEVANCE: The association between periodontitis and CVD in adulthood seems to establish much earlier in life than had been previously studied, giving impetus to preventive approaches focused on their common risk factors.

Impact of resveratrol in the reduction of the harmful effect of diabetes on peri-implant bone repair: bone-related gene expression, counter-torque and micro-CT analysis in rats.

OBJECTIVE: Investigate the impact of resveratrol (RESV) on peri-implant repair and its effect on bone-related markers in rats with induced diabetes mellitus (DM). MATERIAL AND METHODS: Ninety rats were divided into: DM + RESV (n = 18); DM + placebo (PLAC) (n = 18); DM + insulin (INS) (n = 18); DM + RESV + INS (n = 18); Non-DM (n = 18). Diabetes was induced by streptozotocin. One screw-shaped titanium implant was inserted in each tibiae of animals. Treatments were administered during 30 days. After, one of the implants was removed for counter-torque and the peri-implant tissue was collected for mRNA quantification of BMP-2, OPN, Runx2, Lrp-5, Osx, ß-catenin, Dkk1, OPG, and RANKL by Real-time PCR. The other tibia was submitted to MicroCT analysis to measure: bone volume (BV/TV), trabecular thickness (Tb.Th) and bone-implant contact (BIC). RESULTS: Higher counter-torque values were observed for implant removal in DM + RESV, DM + RESV + INS and Non-DM groups when compared to DM + PLAC (p < .05). Augmented Tb.Th was observed in DM + RESV and Non-DM when compared to DM + PLAC group (p < .05), whereas higher BIC was detected in DM + RESV, DM + RESV + INS and Non-DM animals when compared to DM + PLAC (p < .05). Levels of RANKL were downregulated by the RESV and/or INS therapy, whereas only the association of RESV and INS upregulated the levels of Runx2 (p < .05). CONCLUSIONS: The therapy with RESV may favour peri-implant bone repair improving bone formation around implants.

Impact of natural curcumin on the progression of experimental periodontitis in diabetic rats.

OBJECTIVE: To evaluate the role of natural curcumin (CURC) on experimental periodontitis (EP) in animals with diabetes mellitus (DM). MATERIAL AND METHODS: One hundred rats were assigned to DM + placebo (PLA); DM + CURC; DM + insulin (INS); DM + CURC + INS; and Non-DM. Diabetes was induced by streptozotocin. After 3 days, they were initiated CURC and PLAC solutions and insulin administrations, daily for 30 days. This included a period of 19 days prior to EP induction (ligature at the first mandibular and the second maxillary molar) and then additional 11 days. Specimens from the mandible were processed for morphometric examination of bone level. Gingival tissues from mandibular molars were collected for quantification of IL-1ß, IL-4, IL-6, IL-17, IFN-γ, and TNF-α using a Luminex/MAGpix assay. Gingivae from maxillary molars were subjected to RT-PCR for assessment of Runx2, RANKL, OPG, SIRT, Dkk1, and Sost levels. RESULTS: Lower linear bone loss was detected in ligated molars of DM + CURC + INS vs DM + PLAC and DM + INS groups (P < 0.05). In ligated sites from DM rats treated with CURC + INS, IL-6, IL-1ß, INF-γ, and TNF-α levels were the lowest in comparison with PLAC and/or INS and CURC as monotherapies (P < 0.05). CURC, independently of INS, increased Runx2 and SIRT when compared to DM + PLAC (P < 0.05) in ligated sites, whereas only CURC + INS reduced the RANKL/OPG ratio when compared to DM + PLAC (P < 0.05). CONCLUSION: Natural CURC, when associated with INS, reduces the DM-induced loss of supporting alveolar bone and promotes favorable modulation on osteo-immune-inflammatory mediators.

Effect of a single-tufted toothbrush on the control of dental biofilm in orthodontic patients: A randomized clinical trial.

OBJECTIVE: To compare the effect of a single-tufted toothbrush combined or not with a conventional toothbrush to control dental biofilm in healthy orthodontic patients. MATERIALS AND METHODS: Twenty orthodontic patients were randomly assigned to receive three different treatments: Group 1-conventional toothbrush; Group 2-single-tufted toothbrush and Group 3-combination of single-tufted and conventional toothbrushes. Stained plaque index (SPI), visible plaque index (VPI) and gingival bleeding index (GBI) were recorded. The data were analysed by Kolmogorov-Smirnov test. Wilcoxon test was used for intragroup comparison and Friedman test for the intergroup comparison (α = 5%). RESULTS: Intragroup analysis showed that VPI and SPI significantly decreased (P < 0.05) after 72 hour in Group 3. Anterior and posterior teeth did not show any significant statistical differences after 72 hour (P > 0.05), but VPI values in the labial surfaces were different to Group 3 (P < 0.05) in comparison with the other groups after 72 hour. Group 3 showed a statistically significant reduction (P < 0.05) for SPI in the interproximal surfaces when compared with Group 1. CONCLUSION: The combination of single-tufted and conventional toothbrushes was effective for controlling dental biofilm formation in orthodontic patients.

Salivary levels of inflammatory cytokines and their association to periodontal disease in systemic lupus erythematosus patients. A case-control study.

Both Systemic Lupus Erythematosus (SLE) and periodontal disease (PD) present a similar immunological profile mainly characterized by altered cytokine levels. In this study we sought to investigate the salivary levels of inflammatory cytokines and their association with PD in SLE patients. 60 patients with SLE and 54 systemically healthy individuals underwent a full periodontal clinical examination. They were then grouped according to their periodontal status. Stimulated saliva was collected in order to evaluate the salivary levels of interferon (IFN-γ), Interleukin (IL)-10, IL-17, IL-1ß, and IL-4. Systemically healthy individuals with periodontitis (group P) presented higher levels of cytokines when compared to systemically healthy individuals, with no periodontal disease (group S) (p<0.05). Additionally, in the P group, patients presented similar levels of cytokines to those of the patients with SLE, regardless of the presence of PD (p>0.05), for most of the analyzed cytokines. There was a positive correlation in SLE patients, including IL-1ß and all periodontal clinical parameters (p<0.05), and between IL-4 and gingival bleeding index and the presence of biofilm (p<0.05). Thus, our results confirmed, that patients with PD showed higher salivary levels of cytokines and, in SLE patients, the increased levels of salivary cytokines were observed even in the absence of periodontitis. IL-1ß and IL-4 salivary levels were also positively correlated with periodontal status indicating their potential as markers of the amount and extent of periodontal damage in patients with SLE.

Multidisciplinary Treatment of a Fenestration-type Defect.

The case report aimed at treating a fenestration-type defect with multidisciplinary conventional and advanced surgical techniques. Fenestrations are isolated areas in which the exposed root surface is covered only by the periosteum and gingiva, but the remaining cortical bone remains intact. Root coverage is indicated in cases of root hypersensitivity, treatment of shallow caries lesions, cervical abrasions, and esthetic and cosmetic needs. In this case report, after proper hygiene instruction and dental biofilm control, a fenestration-type defect was treated using guided tissue regeneration (anorganic bovine matrix and resorbable membrane) and a connective tissue grafts, associated to an endodontic apicoectomy. After reevaluation, the remaining gingival recession was treated with a second gingival connective tissue graft covered with q double papillae type in order to reconstruct the periodontal tissues of the involved tooth. In this clinical case, the interaction between the different areas of dentistry has made it possible to correct a fenestration-type defect, following procedures based on scientific evidence, restoring periodontal health, esthetics, self-esteem, and meeting the patient's expectations regarding her initial complaint. This case report shows the important role of interdisciplinary approach to treating a patient with a complex periodontal defect that required different types of knowledge and abilities to achieve the best results based on the current status of dentistry possibilities.

Comparative Study on the Periodontal Parameters Used in Diagnosing Periodontitis in Puerperae and Periodontitis' Relationship with the Birth of Preterm Infants: A Case-Control Study.

To compare different criteria for the diagnosis of periodontitis and to evaluate the association of this condition with prematurity, this case-control study was conducted on 283 mothers of infants, divided into two groups based on gestational age (cases: <37 weeks, controls: ≥37 weeks), with 71 cases and 212 controls. The periodontal evaluation included probing depth (PD), clinical attachment level (CAL), plaque index, and bleeding on probing (BOP). Participants were classified regarding periodontitis per 14 criteria based on different periodontal parameters. The criterion selected as the gold standard was the presence of at least four teeth with one or more sites with a PD ≥ 4 mm, CAL ≥ 3 mm, and BOP at the same site. The prevalence of periodontal disease ranged from 8.1% to 55.1%. Moreover, compared to the gold standard, the sensitivities of the other criteria were 100%, while specificity ranged from 50.4% to 96.4%. Periodontitis, defined by six of the selected criteria, was associated with prematurity after multivariate adjustment, with OR ranging from 1.85 to 2.69 and 95% CI from 1.01 to 5.56; one of them was the gold standard mentioned above. Measurements using the clinical parameters of PD, CAL, and bleeding at the same site (criteria 5, 6, 7, 8), CPI (criterion 10), and at least four teeth with a PD ≥ 4 mm and CAL ≥ 3 mm (criterion 11) to define periodontitis showed a statistically significant association (p < 0.05). Given this study's limitations, we can conclude that the diagnostic criteria for a periodontitis definition using a PD ≥ 4 mm and CAL ≥ 3 mm in two or more teeth, with BOP at the same site, seem stronger when detecting an association between periodontitis and prematurity.

Preoperative gingival conditioning as a guide for implant installation and to achieve proper dentogingival contours.

A successful esthetic outcome for implant-supported dentures depends on the careful manipulation of peri-implant tissue as well as the precise placement of the implant. In addition, careful surgical and prosthetic planning is essential for esthetically important areas, especially in partially edentulous cases. This study describes a clinical case that presented absent maxillary central incisors in which prior prosthetic planning was used to perform provisional restorations, that was used to condition the gingival tissues and guide implant installation. These procedures made it possible to achieve a dentogingival contour, interdental papillae, and an emergence profile in the edentulous area. The techniques outlined here proved to be sufficient and support the peri-implant tissues to create a more esthetic final prosthesis.

Evaluation of soft tissues around single tooth implants in the anterior maxilla restored with cemented and screw-retained crowns.

Implant-supported restorations can be attached as screw-retained or cemented prostheses. In both situations, the characteristics of the soft tissues around the implants are crucial for oral rehabilitation and patient satisfaction. Therefore, this study uses the Pink Esthetic Score (PES), which allows evaluation of gingival esthetics around implants, to evaluate the soft tissues around implants in the anterior maxilla rehabilitated with cemented prostheses (CP) and screw-retained prostheses (SP). Forty implants placed in the anterior maxilla were evaluated, and these had been rehabilitated with prosthetic crowns for a minimum of 1 year. Periodontal examination was performed to evaluate probing depth (PD) and bleeding on probing (BOP) of the implant and the corresponding natural tooth. The total mean (±SD) PES for SP was 10.73 (±1.98) and 10.41 (±2.67) for CP, which was not statistically significant (P ≥ .05). Periodontal examination revealed that CP and SP showed no difference for BOP (P ≥ .05). Differences were only detected in PD when comparing the reference teeth of both groups to CP and SP (P ≤ .05). The present study demonstrates that the PES proved to be an efficient index to assess peri-implant tissues, and that the type of crown retention does not influence the health and quality of the soft tissues around implants.

The influence of periodontal status and serum biomarkers on salivary leptin levels in systemic lupus erythematosus patients.

Objective: This study aimed to investigate the influence of periodontal status, clinical data, and serum markers on salivary leptin levels in patients with systemic lupus erythematosus (SLE). Methods: A case-control study was conducted with 38 patients with SLE and 29 healthy controls. Periodontal data included periodontal probing depth (PPD), clinical attachment level (CAL), and gingival bleeding on probing (BOP). Stimulated saliva samples were collected to analyze salivary leptin levels. Clinical and serum data were collected from the SLE group. Statistical analysis included the t-test, Mann-Whitney test, Spearman correlation coefficient, and a structural equation model. Results: The SLE group had a lower salivary leptin level than the control group (P = 0.002). The model revealed that SLE had an inverse and independent effect on salivary leptin (standardized estimate =  - 0.289, P = 0.023). Moreover, salivary leptin level negatively correlated with the serum levels of triglyceride, creatinine, and leukocytes, positively correlated with the serum total cholesterol, but was not significantly correlated with the periodontal status. Conclusion: These findings suggest that patients with SLE have a lower salivary leptin level. In addition, the level of salivary leptin does not appear to be related to periodontal status in patients with SLE.

Improving the esthetic replacement of missing anterior teeth: interaction between periodontics and a rotational path removable partial denture.

The rotational path of insertion concept for removable partial dentures (RPDs) can be used in esthetically demanding situations. This clinical report describes the treatment of a patient with an anterior maxillary edentulous area using a rotational path RPD. To optimally improve gingival esthetics and to allow proximal retention on the surveyors, a crown-lengthening surgical procedure was performed prior to prosthetic treatment on all teeth involved in this rehabilitation. When correctly planned and fabricated, this prosthesis allows excellent functional and esthetic results, minimizes tooth preparation, and reduces the tendency toward plaque accumulation.

Expression of Toll-like receptors 2 and 4 in the saliva of patients with systemic lupus erythematosus and chronic periodontitis.

OBJECTIVE: The aim of this study was to investigate the expression of salivary Toll-like receptors (TRL) 2 and 4 in patients with systemic lupus erythematosus (SLE) and chronic periodontitis (CP). METHODS: A case-control study was conducted with 77 participants (42 SLE and 35 non-SLE) stratified according to CP diagnosis criteria. Periodontal parameters consisted of clinical attachment level (CAL), probing depth (PD), the visible plaque index (VPI), and the gingival bleeding index (GBI). Salivary TRL 2 and 4 expressions were determined by quantitative real-time polymerase chain reaction (RT-PCR). Statistical analysis included Mann-Whitney U test, Kruskal-Wallis test, Spearman's correlation rank, and multiple linear regression. RESULTS: Patients with isolated SLE or CP had higher TLR 2 and TLR 4 expression in their saliva samples (P < 0.05). The group with both SLE and CP had lower TLR 2 and 4 expressions (P < 0.05). TLR 2 and TLR 4 showed significant negative correlations with PD, CAL, and GBI in SLE patients, and a significant positive correlation with periodontal parameters in non-SLE patients. CP was independently associated with reduction of TLR2 and TLR4 expression, even after adjusting for clinical data and current drug use. CONCLUSION: Reduced TRL 2 and 4 expression in saliva was associated with the presence of CP in SLE patients. Key Points • Patients affected by isolated CP or SLE had higher TLR2 and TLR4 expression. • TLR under-expression may be associated with a worse periodontal status in SLE. • Abnormalities in TLRs expression may increase the susceptibility to periodontitis.

Evidence that metyrapone in the presence of inflammation modulates cytokine mRNA expression.

OBJECTIVE: Metyrapone (MT) has been used clinically to decrease glucocorticoid levels in human and animal studies. However, the potential effects of MT in the presence of inflammation are poorly understood. Thus, the aim of this study was to evaluate the effects of the administration of MT on the mRNA levels of pro-inflammatory cytokines in the presence of inflammation induced by the well-established model of ligature-induced periodontitis in rats. MATERIAL AND METHODS: Sixty animals were randomly assigned into three experimental groups of 20 rats each: G1-control; G2-periodontal disease (PD) induced by cotton ligature; G3-PD associated with 3 daily doses of MT (50mg/kg/3×3h). After 30 days, all animals were killed by decapitation. Blood samples were taken and the concentrations of corticosterone and catecholamines measured. Marginal tissues around ligated and non-ligated teeth were harvested and gene expression was assessed by quantitative polymerase chain reaction technique (qPCR). Moreover, the area of interradicular bone loss (ABL) was histometrically determined. RESULTS: Data analysis showed that: (i) ligature placement resulted in a significant ABL, as compared to non-ligated sites of G1 group; (ii) mRNA levels of all the pro-inflammatory factors assessed (INF-γ, TNF-α, IL-1ß and IL-6) were increased in the PD group (G2) (p<0.05) when compared to G1; (iii) there were no significant differences in corticosterone and catecholamine plasmatic levels between the three groups; (iv) MT administration, in the presence of inflammation, induces an increased ABL and significantly increased mRNA levels of all pro-inflammatory cytokines analyzed (p<0.05). CONCLUSION: Within the limits of this study, it can be concluded that MT in the presence of inflammation may modulate expression of pro-inflammatory cytokines, regardless of its effect on plasma corticosterone levels.

Inflammatory and bone-related genes are modulated by aging in human periodontal ligament cells.

Periodontal ligament cells (PDLC) play a major role in periodontal tissues homeostasis and destruction. Most age-associated diseases seem to be closely related to an underlying chronic inflammatory state. Thus, the present study aimed at evaluating in PDLC the effect of aging on the basal levels of inflammatory and bone-related genes. Primary PDLC cultures were obtained from subjects aged 15-20 years (control- n=5), and subjects aged more than 60 years (test- n=5). Proliferation, cell viability and total secreted protein assays were performed, and mRNA levels were quantitatively assessed for interleukin (IL)-1beta, IL-4, IL-6 and IL-8, and for receptor activator of nuclear factor-kappaB ligand (RANKL) and osteoprotegerin (OPG) by real time PCR. Data analysis demonstrated that aging negatively influenced cell proliferation, whereas cell viability and total secreted protein were not affected (p>0.05). Gene expression analysis showed that mRNA levels for RANKL and IL-8 were not affected by aging (p>0.05) whereas, mRNA levels for IL-4 was significantly lower in aged cells (p<0.05) and OPG, IL-1beta and IL-6 mRNA levels were higher (p<0.05). Data analysis suggests that aging decreased the ability of PDLC to proliferate and modulated the expression of important inflammatory and bone-related genes in periodontal ligament cells, favoring a proinflammatory and an antiresorptive profile.

Influence of aging on biological properties of periodontal ligament cells.

The majority of patients eligible for periodontal regenerative therapies are aged subjects. Since periodontal ligament cells (PDLC) are essential for periodontal regeneration, the aim of the present study was to determine the effect of cellular aging on PDLC, including genes associated with extracellular matrix metabolism and growth-associated factors. PDLC cultures were obtained from subjects aged 15 to 20 years and subjects aged more than 60 years. Proliferation, cell viability, mineralization assays, and mRNA levels were assessed for type I and III collagen, platelet-derived growth factor (PDGF)-1, basic fibroblast growth factor (bFGF), metalloproteinase (MMP)-2 and-8, and tissue inhibitor of metalloproteinases (TIMP)-1 and-2. Data analysis demonstrated that aging negatively influenced cell proliferation and mineral nodule formation (p < 0.05). Gene expression analysis further showed that mRNA levels for bFGF, PDGF-1, and TIMP-2 were not affected by aging (p > 0.05). In addition, mRNA levels for type I and III collagen were significantly lower in aged cells (p < 0.05), whereas MMP-2 and-8 and TIMP-1 mRNA levels were higher (p < 0.05). Within the limits of the present study, data analysis suggests that aging modulates important biological properties of periodontal ligament cells, diminishes the potential for mineral nodule formation, and favors extracellular matrix degradation.

Chronic stress may modulate periodontal disease: a study in rats.

BACKGROUND: The present study aimed to evaluate whether chronic stress (CS) affects ligature-induced periodontal disease and to investigate the impact of CS on the mRNA levels of interleukin (IL)-1beta, -1 receptor antagonist, -6, and -10, interferon-gamma (IFN-gamma), receptor activator of nuclear factor-kappa B ligand (RANKL), and osteoprotegerin in the gingival tissues of rats. METHODS: Sixty male Wistar rats were assigned randomly to three groups: G1 (control; non-ligated sites), G2 (periodontal disease), and G3 (periodontal disease associated with restraint stress for 12 hours/day for the entire study). After 30 days, all animals were sacrificed by decapitation. Blood samples were taken, and the concentrations of corticosterone and catecholamines were measured as biomarkers of CS. Marginal tissues around ligated and non-ligated teeth were harvested, and gene expression was assessed by quantitative polymerase chain reaction. Moreover, the area of bone loss (ABL) was determined histometrically. RESULTS: Data analysis showed that CS increased serum levels of stress biomarkers (P <0.05), ligature placement resulted in a significant ABL compared to non-ligated sites, CS significantly increased the amount of ABL in inflamed sites (P <0.001), and CS significantly increased mRNA levels of proinflammatory (IL-1beta and -6 and IFN-gamma) and anti-inflammatory (IL-10) cytokines and proresorptive factor (RANKL) in ligated sites (P <0.05). CONCLUSION: CS significantly increased bone loss resulting from ligature-induced periodontitis by a local increase in proinflammatory and proresorptive factors.

Stem cells: potential therapeutics for periodontal regeneration.

This paper is concerned about dental-derived stem cells and their characterization in vitro and in vivo. Additionally, since conventional periodontal techniques remain insufficient to attain complete and reliable periodontal regeneration, the potential of dental-derived stem cells in promoting periodontal tissue regeneration is also reviewed.

A systematic review of stress and psychological factors as possible risk factors for periodontal disease.

BACKGROUND: Clinical observations and epidemiologic studies suggest that some negative life events and psychological factors may contribute to an increased susceptibility to periodontal disease. The aim of the present study was to systematically review the evidence from case-control studies, cross-sectional studies, and prospective clinical trials reporting on the influence of stress and psychological factors on periodontal disease. The focused question addressed in this systematic review was whether the scientific evidence is enough to consider stress and psychological factors as risk factors for periodontal disease. METHODS: A literature search was conducted using two databases (MEDLINE and the Cochrane Oral Health Group specialist trials register) in addition to searching reference lists of original and review articles. The search strategy used was the combination of the terms: "stress," "periodontal disease," and "psychosocial disorders." Studies were selected if they were published in dental journals between January 1, 1990 and April 1, 2006; only human studies and studies with adults and middle-aged subjects were included. Suitable variables included control for the potential effect of confounding factors, adequate criteria to define periodontal disease, adequate criteria for establishing stress, and methodologic quality. Only English-language articles were considered, and unpublished data were not sought. Two reviewers independently extracted information regarding quality and study characteristics in duplicate. The studies were assessed regarding their methodologic characteristics, statistical analysis, characteristics of the periodontal outcome measures, and psychological measurements. RESULTS: Of the 58 articles identified in the search, 10 were excluded because they were reviews and 34 did not comply with the selection criteria. Fourteen articles (seven case-control studies, six cross-sectional studies, and one prospective clinical trial) were included in the analysis; their quality and main study characteristics were assessed according to the criteria preestablished in the protocol of the study. With regard to the results of the studies, 57.1% found a positive outcome between psychosocial factors/stress and periodontal disease, 28.5% observed a positive outcome for some characteristics and a negative outcome for others, and 14.2% found a negative outcome. CONCLUSIONS: Within the limitations of this systematic review, the majority of studies showed a positive relationship between stress/psychological factors and periodontal disease. However, in the future, well-designed and more representative studies should be considered to confirm these factors as a risk for periodontal disease.