Treatment Of Experimental Periodontitis Research Articles

Preventive and Therapeutic Potential of Streptococcus cristatus CA119 in Experimental Periodontitis in Rats.

Periodontitis is an inflammatory condition of the oral cavity caused by a mixed infection of various bacteria, which not only severely affects the alveolar bone and connective tissues but also displays potential correlations with distal intestinal inflammation. In this study, we aimed to elucidate the therapeutic effects of Streptococcus cristatus CA119 on experimental periodontitis in rats and its impact on intestinal morphology. The results demonstrate that CA119 is capable of colonizing the oral cavity and exerting antagonistic effects on Porphyromonas gingivalis and Fusobacterium nucleatum, thus leading to a significant reduction in the oral pathogen load. Following CA119 intervention, there was a significant alleviation of weight loss in rats induced by periodontitis (P < 0.001). CA119 also regulated the expression of IL-6 (P < 0.05), IL-1β (P < 0.001), IL-18 (P < 0.001), COX-2 (P < 0.001), iNOS (P < 0.001), and MCP-1 (P < 0.01) in the gingival tissue. Additionally, CA119 reduced oxidative stress levels in rats and enhanced their antioxidant capacity. Microcomputed tomography (micro-CT) and histological analysis revealed that CA119 significantly reduced alveolar bone loss and reversed the downregulation of OPG/RANKL (P < 0.001). Furthermore, CA119 exhibited a significant protective effect against intestinal inflammation induced by periodontal disease and improved the colonic morphology in rats. In conclusion, this study demonstrates the role of CA119 as a potential oral probiotic in the prevention and treatment of experimental periodontitis, underscoring the potential of probiotics as a complementary approach to traditional periodontal care.

Analysis of inflammation and bone remodeling of atmospheric plasma therapy in experimental periodontitis.

The biological effects of atmospheric plasma (cold plasma) show its applicability for controlling the etiological factors that involve tissue repair. Thus, the study evaluated the effect of atmospheric plasma therapy in the control of tissue inflammation and bone remodeling in experimental periodontitis. Fifty-six rats were subjected to ligation in the cervical region of the first maxillary molars (8 weeks). The animals were divided into two groups (n = 28): periodontitis without treatment group (P group), and periodontitis with atmospheric plasma treatment group (P + AP group). Tissue samples were collected at 2 and 4 weeks after treatment to analyze the inflammation and bone remodeling by biochemical, histomorphometric, and immunohistochemical analyses. Inflammatory infiltration in the gingival and periodontal ligament was lower in the P + AP group than in the P group (p < .05). The MPO and NAG levels were higher in the P + AP group compared to P group (p < .05). At 4 weeks, the TNF-α level was lower and the IL-10 level was higher in the P + AP group compared to P group (p < .05). In the P + AP group, the IL-1β level increased in the second week and decreased in the fourth week (p < .05), the number of blood vessels was high in the gingival and periodontal ligament in the second and fourth week (p < .05); and the number of fibroblasts in the gingival tissue was low in the fourth week, and higher in the periodontal tissue in both period (p < .05). Regarding bone remodeling, the RANK and RANKL levels decreased in the P + AP group (p < .05). The OPG level did not differ between the P and P + AP groups (p > .05), but decreased from the second to the fourth experimental week in P + AP group (p < .05). The treatment of experimental periodontitis with atmospheric plasma for 4 weeks modulated the inflammatory response to favor the repair process and decreased the bone resorption biomarkers, indicating a better control of bone remodeling in periodontal disease.

Adjunctive effect of 470-nm and 630-nm light-emitting diode irradiation in experimental periodontitis treatment: a preclinical study.

This study investigated the adjunctive effect of light-emitting diodes (LEDs) in the treatment of experimental periodontitis. Experimental periodontitis was induced by placing ligatures around the mandibular second, third, and fourth premolars of 6 beagles for 3 months. After ligature removal, periodontitis progressed spontaneously for 2 months. The animals' hemimandibles were allocated among the following 3 groups: 1) no treatment (control), 2) scaling and root planing (SRP), and 3) SRP with LED irradiation at 470-nm and 630-nm wavelengths (SRP/LED). The probing pocket depth (PPD) and gingival recession (GR) were measured at baseline, 6 weeks, and 12 weeks. The clinical attachment level (CAL) was calculated. After 12 weeks, histological and histomorphometric assessments were performed. The distances from the gingival margin to the apical extent of the junctional epithelium (E) and to the connective tissue (CT) attachment were measured, as was the total length of soft tissue (ST). PPD and CAL increased at 12 weeks compared with baseline in the control group (6.31±0.43 mm to 6.93±0.50 mm, and 6.46±0.60 mm to 7.61±0.78 mm, respectively). PPD and CAL decreased at 12 weeks compared with baseline in the SRP group (6.01±0.59 to 4.81±0.65 mm, and 6.51±0.98 to 5.39±0.93 mm, respectively). PPD and CAL decreased at 12 weeks compared with baseline in the SRP/LED group (6.03±0.39 to 4.46±0.47 mm, and 6.11±0.47 to 4.78±0.57 mm, respectively). The E/ST and CT/ST ratios significantly differed among the 3 groups (P<0.05). The clinical parameters and histologic findings demonstrated that 470-nm and 630-nm wavelength LED irradiation accompanying SRP could improve treatment results. Within the study limitations, 470 nm and 630 nm wavelength LED irradiation might provide additional benefits for periodontitis treatment.

Adjuvant effects of Saccharomyces cerevisiae in the treatment of experimental periodontitis in rats undergoing chemotherapy.

Surgical procedures, radiotherapy, and chemotherapy, individually or in association, are current oncological treatments. Among the most used chemotherapy drugs, 5-fluorouracil (5FU) is an antimetabolite with a broad spectrum of action. This study evaluated the effects of probiotics (PRO) as an adjuvant to the treatment of experimental periodontitis (EP) in rats immunosuppressed with 5FU.108 rats were randomly allocated to six different groups: EP; SS - systemic treatment with saline solution (SS); 5FU - systemic treatment with 5FU; 5FU+PRO - systemic treatment with 5FU, followed by the local administration of Saccharomyces cerevisiae ; 5FU+SRP - systemic treatment with 5-FU, followed by scaling and root planing (SRP); and 5FU+SRP+PRO - systemic treatment with 5FU followed by local treatments with SRP and PRO. Immunosuppression was obtained at two points: at the time of ligature installation and after 48 h. Six animals from each group were euthanized at seven, 15, and 30 d and hemimandibles were collected and processed for histopathological, histometric, and immunohistochemical analysis. Data were subjected to statistical analysis (α=5%). At 7 d, the 5FU+PRO group showed less bone resorption and better structured connective tissue compared with the EP, SS, 5FU+SRP, and 5FU+SRP+PRO groups. At 15 d, the 5FU+SRP group showed a greater intensity of the inflammatory response (p<0.05). At 30 d, the 5FU+SRP+PRO group showed better structured bone tissue and a higher percentage of bone tissue (PBT) than the EP, SS, 5FU, and 5FU+PRO groups (p<0.05). The use of Saccharomyces cerevisiae as monotherapy or as an adjuvant to periodontal therapy may have a positive effect on bone repair in immunosuppressed conditions.

Effects of Atmospheric Pressure Plasma in the Treatment of Experimental Periodontitis in Beagle Dogs.

The specific objective of this study was to evaluate the effects of atmospheric pressure plasma (APP) in the treatment of experimental periodontitis in Beagle dogs. The APP jet was diagnosed using optical emission spectroscopy and laser-induced fluorescence spectroscopy. Six Beagles received stainless steel ligatures to establish experimental periodontitis model. The teeth in the control group were subjected to conventional root surface debridement (RSD) and chlorhexidine irrigation. The APP group also started with RSD and was then subjected to plasma irradiation. Clinical analyses including plaque index, modified sulcus bleeding index, pocket depth and attachment loss (AL), as well as cone-beam computed tomography (CBCT) analysis, were performed at baseline, 4th week, 8th week and 12th week after treatment. The results showed that typical reactive oxygen and nitrogen species were found in the full spectrum and the gas temperature of APP was close to room temperature. The highest concentrations of hydroxide and oxygen were obtained at 5 mm away from the nozzle. In both groups, all values in clinical examinations were significantly lower (P<0.05) at 12th week after treatment than those at baseline. At the 12th week, the AL in clinical examinations and the bone loss in CBCT images in the APP group were significantly lower than those in the control group (P<0.05). The hematoxylin-eosin staining showed more renascent alveolar bone in the APP group than in the control group. These findings suggested that APP has profound potential for use as an adjunct approach for periodontitis treatment.

Assessment of the Effect of Local Administration of Placental Extract Gel on the Treatment of Experimental Periodontitis in Rats: A Histopathologic and Immunohistochemical Study.

Assessment of the Effect of Local Administration of Placental Extract Gel on the Treatment of Experimental Periodontitis in Rats: A Histopathologic and Immunohistochemical Study.

The effects of Lactobacillus reuteri on the inflammation and periodontal tissue repair in rats: A pilot study

ObjectiveThe aim of this study was to evaluate the effects of probiotic (PRO) Lactobacillus reuteri (DSM17938) as an adjuvant to the treatment of experimental periodontitis (EP). Material and methodsFifty-four male adult Wistar rats were included. EP was induced and maintained for 7 days. Subsequently, the ligature was removed and the animals were allocated into three different experimental groups (n = 18/group): EP – no local treatment, the animals received four systemic saline solution (SS) administrations; SRP+SS, the animals underwent SRP treatment, followed by SS administration; and SRP+PRO, the animals received SRP treatment, followed by the systemic administration of PROs (Lactobacillus reuteri ; 0.16 ml/day). Six animals from each group were euthanised at 7, 15 and 30 days. Histological and histometric analyses of alveolar bone loss (BL) and immunohistochemical analyses for TRAP, RANKL, OPG, OCN, and PCNA were performed. Shapiro–Wilk, ANOVA, post-hoc Tukey, Kruskal–Wallis, Student–Newman Keuls were performed. ResultsThe SRP+PRO group presented a reduction in inflammation. At 15 days, a lower BL was observed in the SRP+SS and SRP+PRO groups. Greater immunolabeling was noticed for PCNA at 15 days in the SRP+PRO group than in the SRP+SS group. The SRP+PRO group demonstrated a higher OCN immunolabeling pattern than the EP group at 15 and 30 days. ConclusionThe use of Lactobacillus reuteri as an adjuvant to SRP for the treatment of EP showed promising results in the control of local inflammatory responses, and enhanced the periodontal tissue repair process according to the employed concentration.

Resolvins as a Treatment Modality in Experimental Periodontitis: A Systematic Review of Preclinical Studies.

This systematic review aimed to assess scientific data of existing literature to identify the efficacy of resolvins (Rv) in the treatment of periodontitis. The electronic databases, Web of Science (WOS), Medline/PubMed, The Cochrane Library, Scopus, and Saudi digital library (SDL), were searched for eligible studies in the field of periodontics. A thorough analysis of the retrieved literature provided five articles that were assessed and included in this systematic review. The quality of these studies was assessed by updated Essential Animal Research: Reporting of In-Vivo Experiments (ARRIVE) guidelines. The five included studies were published between 2005 and 2018 and investigated resolvins as a treatment approach in experimental periodontitis of animals. Among the study animals employed, New Zealand white rabbits were used in three studies, Wistar rats and Albino mice in two studies, respectively. Four studies have evaluated eicosapentaenoic acid-derived RvE1, and one study evaluated docosahexaenoic acid-derived RvD2. Oral-topical application of Rv was followed in four studies, and intra-peritoneal Rv injection was administered in one study. The study duration in these studies have ranged between 4-12 weeks, and the Rv dose was between 0.1 μg to 0.5 μg. One study evaluated the influence of RvE1 topical application on both the prevention and treatment of experimental periodontitis. Resolvins (RvE1 and RvD2) have been studied in periodontitis-induced animal models to assess their potential role in periodontal inflammation resolution. There are promising preclinical data of using resolvins as a treatment modality in experimental periodontitis. Resolvins have been demonstrated to inhibit the destructive inflammatory process and alveolar bone loss in laboratory-induced periodontitis under controlled experimental conditions.

Effect of systemic administration of silver nanoparticles in treatment of experimental periodontitis in albino rats

ABSTRACTIntroduction: Periodontal disease is one of the main dental diseases that affectmillions of people around the world. Modern nanotechnology progression andrenovations through nanodentistry providing a suitable solution for the treatment of manydental illnesses including periodontal disease. Aim: Histological and ultrastructuralevaluation of the effect of silver nanoparticles in treatment of periodontitis in albinorats. Materials and methods: A total of 18 adults male albino rats with body weightranging from 150 to 180 gm were used and divided into three groups group 1: served ascontrol, group 2: used for induction of experimental periodontitis using wiring aroundthe cervix of mandibular central incisors for two weeks, and group 3: after induction ofexperimental periodontitis as in group 2 they were subjected to intraperitoneal injectionwith silver nanoparticles for the treatment of periodontitis three times per week for fourweeks. Results: Histological and ultrastructural investigation revealed that periodontalligament around ligated mandibular incisors showed marked improvement in thedegenerated fibers after injection with silver nanoparticles in group 3 compared togroup 2 as the fibers regained their association in strong bundles and they regained theirattachment to regenerated bone and tooth surface. Conclusions: Marked regenerationof the periodontium of periodontally affected ligated mandibular incisors reflected thatsilver nanoparticles have a great anti-inflammatory effect

Comparative effects of different phenothiazine photosensitizers on experimental periodontitis treatment.

The aim of the present study was to compare the effects of the phenothiazine photosensitizers methylene blue (MB), toluidine blue-O (TBO) and butyl toluidine blue (BuTB) in antimicrobial photodynamic therapy (aPDT), as adjuvant therapy to scaling and root planing (SRP) in the treatment of experimental periodontitis (EP) in rats. 120 Wistar rats underwent ligation around the lower left molar. After seven days, the ligature was removed. The animals were separated into the following groups (n = 15): EP, no treatment; SRP, SRP and irrigation with saline solution; MB, SRP and deposition of MB; TBO, SRP and deposition of TBO; BuTB, SRP and deposition of BuTB; MB-aPDT, SRP and aPDT with MB; TBO-aPDT, SRP and aPDT with TBO and; BuTB-aPDT, SRP and aPDT with BuTB. The aPDT session was performed after SRP, with deposition of the photosensitizer and irradiation with a diode laser (DL; InGaAlP, 660 nm, 40 mW, 60 s, 2.4 J). Histological and histometric analysis was performed. BuTB-aPDT group had a lesser extent of the inflammatory process compared to the EP, SRP, MB and TBO at all experimental periods (p < 0.05). At 15 days, the aPDT treated groups had a greater bone tissue structure than groups EP and SRP (p < 0.05) The BuTB showed lower Alveolar Bone Loss (ABL) compared to the TBO-aPDT group at 30 days (p < 0.05). aPDT using the photosensitizer BuTB proved to be the adjuvant therapy that most favored the reduction of inflammatory infiltrate in the furcation area and ABL.

The evaluation of healing effect of triclosan and flurbiprofen-loaded nanogels in experimental periodontitis in rats by morphometric analysis

PurposeTo evaluate therapeutic effectiveness of antibacterial triclosan (TCS) and anti-inflammatory flurbiprofen (FLB)-loaded nanogels system in ligature-induced experimental periodontitis in rats. MethodologyA total of 72 Sprague–Dawley rats were used in this study. Four groups (n = 18 each) were randomly created: Group 1 – neither subjected to experimental periodontitis nor to any treatment; Group 2 – subjected to experimental periodontitis but not treated; Group 3 – subjected to experimental periodontitis and then treated with the developed nanogels; Group 4 – subjected to experimental periodontitis and then placed on a mixture of pure TCS and FLB treatment. The experimental periodontitis was induced on the lower incisors by applying a ligature which was kept for 14 days. Treatment was done for 7 days, and sampling was done at 7, 14, and 28 day of the post-induction experimental period. Morphometric analysis was conducted to assess the clinical outcomes and healing effect. ResultsThe morphometric findings showed that the group treated with the developed TCS and FLB-loaded nanogels recovered better and faster than a mixture of pure TCS and FLB. At 28 day of the experimental period, there was no significant difference (p > 0.05) between the baseline control group and the nanogels treated group. ConclusionsThe developed TCS and FLB-loaded nanogels was found to be effective in the treatment of experimental periodontitis in rats. The used experimental periodontitis model was found to be simple and easily reproducible.

Topical sodium alendronate combined or not with photodynamic therapy as an adjunct to scaling and root planing: Histochemical and immunohistochemical study in rats.

The purpose of this study was to evaluate influence of topical sodium alendronate (ALN), photodynamic therapy (aPDT), or a combination thereof as adjuvant to scaling and root planing (SRP) in the treatment of experimental periodontitis in rats. Therapeutic protocols to control periodontitis progression that aim to equalize bacterial action and load with tissue immune response are well addressed in current scientific research. Experimental periodontitis was induced in 96 rats with a ligature around the mandibular left first molar. After 7days, ligature was removed and animals were treated according to the following experimental groups (n=8): control-SRP plus saline solution; ALN-SRP plus ALN; aPDT-SRP plus methylene blue irrigation, followed by low-level laser therapy (LLLT); and ALN/aPDT-SRP plus ALN and methylene blue irrigation followed by LLLT. The animals were euthanized at 7, 15, and 30days after treatments. Collagen maturation (picrosirius red staining) and immunohistochemical analyses (TRAP, RANKL and osteoprotegerin [OPG]) were performed. Data were submitted to statistical analysis (P<.05). At 7days, group ALN presented a significantly higher number of TRAP-positive cells and percentage of immature collagen fibers than group ALN/aPDT, while group ALN/aPDT presented a significantly higher percentage of mature collagen fibers than group ALN. At 30days, group ALN presented significantly lower percentage of immature collagen fibers and higher percentage of mature collagen fibers than control. It can be concluded that topical use of ALN coadjutant to SRP, alone or combined with aPDT, enhanced collagen maturation and reduced osteoclastogenesis during the healing of experimental periodontitis.

Local Use of Apisan Gel, A New Oral Care Product in the Treatment of Experimental Periodontitis Against the Background of Hyperacid Gastritis and Intoxication with Tobacco Smoke.

The aim of the work was to substantiate the use of a newly created oral care product in the treatment of periodontal disease reconstructed against the background of hyperacidic gastritis under the conditions of tobacco smoke intoxication. The study was conducted in 2 stages. In the first stage, all experimental animals were divided into 4 groups: 1) intact, 2) with simulated periodontitis, 3) with reproduced periodontitis against the background of reproduced hyperacidic gastritis, 4) with reproduced periodontitis against the background of hyperacid gastritis under the conditions of tobacco smoking. Biochemical studies of gum homogenate with periodontitis in rats were conducted to determine the impact of stomach pathology and tobacco smoke as endogenous and exogenous risk factors. In stage 2, the effectiveness of local therapy with the use of the newly created oral care product and a comparator was studied in rats with reproduced periodontitis against the background of hyperacidic gastritis under the conditions of smoking. In the experimental periodontitis against the background of hyperacidic gastritis under the conditions of tobacco smoking, there were significant changes in the periodontal tissues characteristic of the inflammatory process: the activity of peroxide oxidation of lipid (POL) increased, activity of the antioxidant system decreased, and inflammatory markers increased when nonspecific protection was reduced. Local therapy in the rats using the new "Apisan" gel resulted in the correction of certain metabolic disorders, faster elimination of the harmful effects of the damaging factors, and restoration of the condition of periodontal tissues compared with the use of the comparator, the Asepta gel. The therapeutic effectiveness of the new Apisan gel is due to the normalizing effect on the processes of POL, and inflammation and activation of the oral cavity protective systems during inflammatory periodontal disease occurring against the background of a concomitant stomach pathology, hyperacidic gastritis.

Effect of photobiomodulation therapy as an adjunct to scaling and root planing in a rat model of ligature-induced periodontitis: a histological and radiographic study.

This study aimed to histologically and radiographically evaluate the effectiveness of low-intensity laser irradiation of different wavelengths (660 or 808nm) as an adjunct to scaling and root planing in the treatment of experimental periodontitis in rats. Periodontitis was induced by placing a ligature around the mandibular first molar of the rats. In total, 40 Wistar rats were randomly divided into five groups (n = 8 each): control (CG), periodontal disease (PD), scaling and root planing (SRP), SRP + 660nm laser (GL660) and SRP + 808nm laser (GL808). Groups with laser use received radiation at 6 points in the first molar. The animals were euthanized at baseline and at 7 and 14days after the interventions. Mandibles were surgically removed for histomorphometric and radiographic assessment of periodontal tissues. The GL660 group showed lesser bone loss than the PD group (P < 0.05) and greater alveolar bone margin after 14days, indicating a better long-term treatment response (P < 0.05). These findings suggest that SRP with the 660nm laser as an adjunct results in more favorable radiographic and histological responses than the 808nm laser.

Treatment of experimental periodontitis with chlorhexidine as adjuvant to scaling and root planing

ObjectivesTo assess whether subgingival irrigation with 0.12 % or 0.2 % chlorhexidine (CHX) immediately after scaling and root planing (SRP) enhances periodontal tissue repair compared to irrigation with saline solution (control). Materials and methodsPeriodontitis was ligature-induced in rat molars for 7 days. Animals were distributed into three groups: 1) SRP group, SRP and irrigation with 0.9 % saline (n = 30); 2) SRP + 0.12 % CHX group, SRP and irrigation with 0.12 % CHX (n = 30); 3) SRP + 0.2 % CHX group, SRP and irrigation with 0.2 % CHX (n = 30). Animals were killed at 7, 15, and 30 days after treatment. Furcation region was histometrically analyzed to determine the bone area. Immunohistochemical reactions were performed for receptor activator of nuclear factor-kB ligand (RANKL), osteoprotegerin (OPG) and tartrate-resistant acid phosphatase (TRAP). ResultsBoth chlorhexidine groups presented less inflammation and improved tissue repair along the entire experiment when compared with the SRP group. In the histometric analysis at 7, 15 and 30 days, SRP group (4.58 ± 2.51 mm2, 4.21 ± 1.25 mm2, 3.49 ± 1.48 mm2), showed statistically less bone area than groups SRP + 0.12 % CHX (1.86 ± 1.11 mm2; 0.79 ± 0.27 mm2; 0.34 ± 0.14 mm2) and SRP + 0.2 % CHX (1.14 ± 0.51 mm2; 0.98 ± 0.40 mm2; 0.41 ± 0.21 mm2). Both chlorhexidine concentrations modulated the expression of TRAP, RANKL and OPG. ConclusionsSubgingival irrigation with chlorhexidine contributed for a quicker shift from a proinflammatory destructive profile to healing of periodontal tissues.

Multiple aPDT sessions on periodontitis in rats treated with chemotherapy: histomorphometrical, immunohistochemical, immunological and microbiological analyses.

The aim of this study was to evaluate the effect of multiple sessions of antimicrobial photodynamic therapy (aPDT) on the treatment of experimental periodontitis (EP) in rats treated with chemotherapy. Chemotherapy using 5-fluorouracil (5-FU) consisted of intraperitoneal administration of 60 and 40 mg/kg of 5-FU. 120 rats were subjected to chemotherapy with 5-FU and divided into groups: PT (periodontal treatment); PT+1aPDT (PT and single aPDT session); PT+4aPDT(PT and 4 sessions of aPDT); 1aPDT (single aPDT session); 4aPDT(4 sessions of aPDT). EP was induced in the mandibular molars via ligature placement. The alveolar bone loss (ABL) area in the furcation region was analysed histometrically. Proliferating cell nuclear antigen (PCNA), tartrate-resistant acid phosphatase (TRAP), receptor activator of nuclear factor kappa-B ligand (RANKL), osteoprotegerin (OPG) and cleaved caspase-3 (CC3) were analysed by immunohistochemistry. Prostaglandin E2 was quantified using an ELISA, tumor necrosis factor (TNF)-α and interleukin (IL)-6 were assessed using a multiplex method. The prevalence of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella nigrescens, Prevotella intermedia and Fusobacterium nucleatum was assessed using PCR. The data were statistically analysed (P < 0.05). The PT+4aPDT group showed lower ABL than the PT or 1aPDT groups on day 7. Rats treated with aPDT showed a higher number of PCNA-positive cells with reduced immunolabeling of RANKL. Significant reductions in Prevotella nigrescens were observed in the PT+4aPDT group and in Aggregatibacter actinomycetemcomitans for the 1aPDT and 4aPDT groups. Repeated sessions of aPDT as an adjunct or alternative therapy were effective at reducing ABL, regulating bone metabolism, and reducing Prevotella nigrescens and Aggregatibacter actinomycetemcomitans.

Evaluation of the efficacy of Hylotelephium purpureum gel in the treatment of experimental periodontitis.

Local drug delivery systems have been proposed for the treatment of periodontitis, and Hylotelephium purpureum may be a suitable agent for use in such a system. The present study aimed to formulate a Hylotelephium purpureum gel (HPG) and evaluate the anti-inflammatory activity and antinociceptive effects of Hylotelephium purpureum and to assess the duration of action and efficacy of HPG in the treatment of experimental periodontitis in a KM mouse model. First, an acute toxicity study was performed, and secondly, xylene-induced mouse-ear edema, acetic acid-induced mouse peritoneal capillary permeability and carrageenan-induced hind-paw edema tests were used to investigate the anti-inflammatory activity of the gel. The acetic acid-induced writhing response and hot-plate tests were used to evaluate the antinociceptive activity. The therapeutic effects of HPG in experimental periodontitis were evaluated and minimum inhibitory concentration of the gel was determined. The results showed that intragastrically administration of 80 ml/kg of HPG produced no toxic effects. There were statistically significant changes in gingival indexes and sulcus bleeding indexes in the high-dose HPG-treated group. The serum levels of superoxide dismutase and glutathione peroxidase were significantly heightened, while the level of malondialdehyde was decreased. HPG exhibited 32.7% inhibition of edema, and altered the peritoneal capillary permeability in mice. The gel had relatively good bacteriostatic and bactericidal effects. It also exhibited antinociceptive activity, as demonstrated by the acetic acid-induced writhing response test and hot-plate test. In summary, the present study demonstrates that HPG is effective in the treatment of experimental periodontitis.

Effects of the probiotic Bifidobacterium animalis subsp. lactis on the non-surgical treatment of periodontitis. A histomorphometric, microtomographic and immunohistochemical study in rats.

Lactobacillus probiotics have been investigated in periodontitis. However, the effects of the genus Bifidobacterium on periodontitis are hardly known. This study evaluated the effects of the probiotic (PROB) Bifidobacterium animalis subsp. lactis (B. lactis) HN019 as an adjunct to scaling and root planing (SRP) in rats with experimental periodontitis (EP). At baseline, 32 rats were assigned to 4 groups: C (control), PROB, EP-SRP and EP-SRP-PROB. In groups EP-SRP and EP-SRP-PROB, the mandibular first molars of the animals received a ligature. At day 14, the ligatures were removed and SRP was performed. Animals of groups PROB and EP-SRP-PROB were orally administered with 10 mL/day of 109 colony forming units of B. lactis HN019 for 15 days, starting at day 14. Animals were euthanized at day 29. Histomorphometric, microtomographic and immunohistochemical analyses were performed. Microbiological effects of B. lactis on biofilm were also evaluated. Data were statistically analyzed (ANOVA, Tukey; Kruskal-Wallis, Dunn’s; Two-tailed t-test; p<0.05). Group EP-SRP-PROB presented reduced alveolar bone resorption and attachment loss when compared with Group EP-SRP (p<0.05). Group EP-SRP-PROB showed significantly fewer osteoclasts, increased expression of anti-inflammatory cytokines and reduced expression of proinflammatory cytokines compared with Group EP-SRP (p<0.05). B. lactis promoted a higher ratio between aerobic and anaerobic bacteria in biofilm samples (p<0.05). B. lactis HN019 may have a role in the treatment of EP in rats, as an adjunct to SRP.

Favourable effects of Bacillus subtilis and Bacillus licheniformis on experimental periodontitis in rats

ObjectivesThe purposes of this study were to evaluate, in rats: i) the effects of Bacillus species on the development of experimental periodontitis (EP) via microtomographic, immunological and hematological assays (Experiment 1—E1); ii) the effects of Bacillus species as adjuncts to scaling and root planing (SRP) for the treatment of EP via histomorphometric and immunohistochemical analyses (Experiment 2—E2). MethodsIn E1, 24 rats were divided into groups C1 (control), PROB1, EP1 and EP-PROB1. In groups with EP, the mandibular first molar of each animal received a ligature for 14days. In groups PROB1, animals received Bacillus species for 44days, starting 30days before EP induction in Group EP-PROB1. In E2, 24 rats were assigned to groups C2 (control), PROB2, EP-SRP2 and EP-SRP-PROB2. In groups with SRP, EP was induced as described in E1. The ligatures were removed after 14days and SRP was performed. In groups PROB2, animals received Bacillus species for 15days, starting after SRP in Group EP-SRP-PROB2. ResultsIn E1, Group EP1 presented bone loss (BL) and eosinophil numbers greater than Group EP-PROB1 (P<0.05). In Group EP-PROB1, the receptor activator of nuclear factor-kB ligand (RANKL)/osteoprotegerin (OPG) ratio was similar to that of groups without EP. In E2, Group EP-SRP-PROB2 presented fewer TRAP-positive osteoclasts, lower immunolabeling pattern for a proinflammatory cytokine and decreased BL and attachment loss than Group EP-SRP2 (P<0.05). ConclusionsBacillus species supplementation provided a protective effect against BL and enhanced the effects of SRP in the treatment of EP in rats.

Effect of low-level laser therapy as an adjuvant in the treatment of periodontitis induced in rats subjected to 5-fluorouracil chemotherapy.

This study aimed to assess the effect of multiple sessions of a low-level laser therapy (LLLT) adjuvant to scaling and root planing (SRP) on the treatment of experimental periodontitis (EP) in rats treated with 5-fluorouracil (5-FU). A total of 120 rats were divided into five groups: no treatment (NT); treatment with 5-FU (60 and 40 mg/kg) and no local periodontal treatment (5FU); treatment with 5-FU and SRP (5FU-SRP); treatment with 5-FU, SRP and one LLLT session (660 nm; 0.035 W; 4.2 J; 120 s) (5FU-SRP-1LLLT); and treatment with 5-FU, SRP and four LLLT sessions (0, 24, 48 and 72 h) (5FU-SRP-4LLLT). EP was induced in the mandibular molars through ligature placement. The alveolar bone loss (ABL) area in the furcation region was analysed histometrically. TRAP, proliferating cell nuclear antigen, RANKL, osteoprotegerin and activated caspase-3 patterns were analysed by immunolabeling. Prostaglandin E2 was quantified using an ELISA, and tumour necrosis factor α and interleukin-6 were assessed using the multiplex method. The prevalence rates of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella nigrescens, Prevotella intermedia and Fusobacterium nucleatum were assessed using the PCR method. The data were subjected to statistical analysis (α = 5%). 5FU, 5FU-SRP and 5FU-SRP-1LLLT treatment groups showed higher ABL compared with the NT group (p < 0.05), whereas the 5FU-SRP-4LLLT group showed lower ABL compared with the 5FU group on day 7 and decreased RANKL immunolabeling (p < 0.05). Treatment with 5-FU worsened EP, and multiple LLLT sessions adjuvant to SRP seemed to improve periodontitis in rats subjected to 5-FU chemotherapy.