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.

Smoking habit modulates peri-implant microbiome: A case-control study.

BACKGROUND AND OBJECTIVE: Smoking is a recognized risk factor for peri-implant disease and leads to microbiological changes in mucositis and peri-implantitis. However, there is no knowledge about the impact of smoking in healthy peri-implant tissue. The aim of the study was to evaluate the microbiome in a peri-implant environment in smokers with healthy peri-implant conditions. METHODS: Peri-implant biofilm was collected around single clinically healthy, screwed-retained, teeth-surrounded implants in 12 non-smoker (NSMK) and 12 smoker (SMK) non-periodontitis subjects (no bleeding and probing depth <4 mm). Bacterial DNA was isolated and 16S ribosomal RNA gene libraries were sequenced using pyrosequencing, targeting the V3-V4 region. Datasets were processed using the Quantitative Insights into Microbial Ecology, Greengenes and the Human Oral Microbiome Database databases. RESULTS: An evident difference in the SMK peri-implant microbiome was observed compared to the NSMK microbiome, with a large abundance of species, even with a healthy peri-implant. The SMK core-microbiome showed an abundance of Fusobacterium, Tannerella and Mogibacterium, while the NSMK core revealed an abundance of Actinomyces, Capnocytophaga and Streptococcus, genera that are usually related to periodontal health. The microbiome inter-relationship was shown to be more inter-generic in SMK then in NSMK, indicating different microbiome cohesion. CONCLUSION: Smoking negatively affected the peri-implant microbiome, leading to a disease-associated state, even in clinically healthy individuals.

Occurrence of peri-implant diseases and risk indicators at the patient and implant levels: A multilevel cross-sectional study.

BACKGROUND: High prevalence rates of peri-implant diseases have been reported; however, the lack of standardization of definition criteria has lead to variations in the observed estimates. In addition, scarce data are available concerning patient and implant related factors associated to peri-implantitis. The aim of this study was to determine the prevalence of peri-implant diseases and their risk indicators at the patient and implant levels. METHODS: One hundred forty-seven patients with 490 dental implants were included. Dental implants were clinically and radiographically evaluated to determine their peri-implant conditions. Patient-related conditions and implant and prosthetic-related factors were recorded. Multivariable Poisson regression was fitted and prevalence ratios (PR) were reported. RESULTS: 85.3% of implants (95%CI 80.2 to 90.4) had mucositis and 9.2% (95%CI 4.7 to 13.7) had peri-implantitis. 80.9% (95%CI 73.8 to 86.8), and 19.1% (95%CI 12.6 to 25.5) of patients had mucositis and peri-implantitis. At the patient level, it was observed an increased probability of peri-implantitis in individuals with pocket depths ≥6 mm (PR = 2.47) and with ≥4 implants (PR = 1.96). Smoking increased the probability of peri-implantitis by three times (PR = 3.49). The final multilevel Poisson regression model at the implant level indicated that platform switching reduced the probability of peri-implantitis (PR = 0.18) and implants in function for ≥5 years increased this probability (PR = 2.11). The final model including patient and implant level indicators demonstrated that higher time of function (PR = 2.76) and smoking (PR = 6.59) were associated with peri-implantitis. CONCLUSION: Peri-implant diseases are highly prevalent in the studied sample, and factors associated with the occurrence of peri-implantitis were presence of pockets ≥6 mm, smoking, time of function, and type of platform.

Impact of a triclosan-containing toothpaste during the progression of experimental peri-implant mucositis: Clinical parameters and local pattern of osteo-immunoinflammatory mediators in peri-implant fluid.

BACKGROUND: This study evaluated the influence of a triclosan-containing toothpaste in the profile of osteo-immunoinflammatory mediators in peri-implant crevicular fluid (PICF) and in clinical parameters during progression of peri-implant mucositis. METHODS: Twenty-two clinically healthy patients with an implant-supported single-unit crown were enrolled in this double-blind, randomized, crossover study carried out in two phases of 21 days each. During an experimental 3-week period of undisturbed plaque accumulation in the implants, patients were randomly assigned to use three times/day: triclosan (n = 11), triclosan/copolymer/fluoride toothpaste; or placebo (n = 11), fluoride toothpaste. After a professional prophylaxis, a washout period of 30 days was established. Clinical parameters and 15 osteo-immunoinflammatory mediators in the PICF were evaluated at baseline and at 3, 7, 14, and 21 days. RESULTS: Both groups showed increase in plaque index at implant sites from the 3rd until the 21st day (P < 0.05). Only triclosan treatment was able to avoid an increase in bleeding on probing (BOP) throughout the follow-ups (P > 0.05), whereas a significant intensification in BOP was observed from the 14th day in the placebo-treated sites (P < 0.05). Lower interleukin (IL)-10 concentrations were detected in the placebo group at the 21st day when compared with triclosan-treated implant sites (P < 0.05). IL-10 levels were reduced and IL-1ß concentrations were increased at 21 days when compared with baseline only in placebo-treated sites (P < 0.05). Osteoprotegerin levels significantly increased from the 14th until the 21st day only in triclosan-treated sites (P < 0.05). CONCLUSION: Triclosan-containing toothpaste controls clinical inflammation and interferes positively in the profile of osteo-immunoinflammatory mediators during progression of experimental peri-implant mucositis.

Resveratrol Inhibits Periodontitis-Related Bone Loss in Rats Subjected to Cigarette Smoke Inhalation.

BACKGROUND: Alternative therapeutic approaches have been explored to modulate host response to periodontal disease. Knowledge of new strategies to treat periodontitis is particularly relevant in patients presenting augmented risk to periodontitis, such as smokers. The aim of this study is to investigate the impact of resveratrol (RESV) on progression of experimental periodontitis (EP) in the presence of cigarette smoke inhalation (CSI). METHODS: Rats were assigned to one of three groups: 1) CSI+RESV (n = 20); 2) CSI+placebo (n = 20); and 3) non-CSI (n = 20). CSI was initiated 1 week prior to initiation of RESV or placebo administration (systemically for 30 days) and was continued until the end of the study. EP was induced around the first mandibular and second maxillary molars using ligatures. Specimens from the mandible were processed for morphometric and microcomputed tomography examination of bone volume/levels. Gingival tissues surrounding mandibular molars were collected for quantification of interleukin (IL)-1ß, IL-4, IL-6, IL-17, and tumor necrosis factor-α using an assay system. Additional analyses of immunoinflammatory mediator performance (T-helper Type 17 [Th17]/Th2 and Th1/Th2 cell levels) were performed according to Th cell responses in gingival tissues. Gingival tissues of maxillary molars were subjected to real-time polymerase chain reaction for assessment of osteoprotegrin, runt-related transcription factor-2, receptor activator of nuclear factor-kappa B ligand (RANKL), sclerostin, and Dickkopf Wnt signaling pathway inhibitor 1 levels. RESULTS: Higher linear alveolar bone loss (ABL) and lower interradicular bone density were detected in ligated molars in the CSI+placebo group (P <0.05). IL-4 level was the highest, and Th17/Th2 levels were the lowest in RESV-treated rats compared with placebo rats (P <0.05). RESV reduced expression of messenger RNA for RANKL in animals receiving CSI (P <0.05). CONCLUSION: RESV inhibits EP and CSI-induced supporting ABL and has a beneficial effect on osteo-immunoinflammatory markers.

Photodynamic therapy during supportive periodontal care: clinical, microbiologic, immunoinflammatory, and patient-centered performance in a split-mouth randomized clinical trial.

BACKGROUND: This study investigates the effect of photodynamic therapy (PDT) as monotherapy during supportive periodontal therapy. METHODS: A split-mouth, randomized controlled trial was conducted in patients with chronic periodontitis (N = 22) presenting at least three residual pockets (probing depth [PD] ≥5 mm with bleeding on probing [BOP]). The selected sites randomly received the following: 1) PDT; 2) photosensitizer (PS); or 3) scaling and root planing (SRP). At baseline and 3 and 6 months, clinical, microbiologic (real-time polymerase chain reaction analyses), cytokine pattern (multiplexed bead immunoassay), and patient-centered (regarding morbidity) evaluations were performed. RESULTS: All therapies promoted similar improvements in clinical parameters throughout the study (P <0.05), except that BOP was not reduced in the PS protocol (P >0.05). Lower levels of Aggregatibacter actinomycetemcomitans were observed in the PDT and SRP protocols at 3 months when compared with the PS protocol (P <0.05). An inferior frequency detection of Porphyromonas gingivalis was observed in the PDT protocol at 3 and 6 months and in the SRP protocol at 6 months from baseline (P <0.05). In addition, PDT protocol presented inferior frequency of P. gingivalis at 3 months when compared with the other therapies (P <0.05). Only patients in the PDT protocol exhibited augmented levels of anti-inflammatory interleukin (IL)-4 and reduced proinflammatory IL-1ß and IL-6 throughout the study (P <0.05). Intergroup analyses showed reduced IL-10 and increased interferon-γ and IL-1ß levels in the PS protocol when compared with the other therapies during follow-ups (P <0.05). No differences in morbidity were observed between the therapies (P >0.05), although the need for anesthesia was higher in SRP-treated sites (P <0.05). CONCLUSION: PDT as an exclusive therapy may be considered a non-invasive alternative for treating residual pockets, offering advantages in the modulation of cytokines.

Esthetic treatment of gingival hyperpigmentation with Nd:YAG laser or scalpel technique: a 6-month RCT of patient and professional assessment.

This double-masked, randomized controlled trial with a split-mouth design aimed to compare patient- and professional-centered outcomes using different therapeutic approaches-neodymium-yttrium aluminum garnet (Nd:YAG) laser or scalpel technique-for gingival depigmentation. Patients presenting bilateral melanin gingival hyperpigmentation and who requested cosmetic therapy were recruited. Contralateral quadrants were randomly assigned to receive Nd:YAG laser (settings: 6 W, 60 mJ/pulse, and 100 Hz) or scalpel technique. Patient morbidity experienced at intratherapy and during the first postoperative week was evaluated. In addition, after 6 months, the cosmetic results achieved for the different therapeutic approaches were evaluated by patients and professionals. The chair time of each technique was also calculated. Patient-oriented outcomes concerning intratherapy morbidity did not demonstrate any differences between groups (p > 0.05), although a higher extent of discomfort/pain was experienced in the side treated by the scalpel technique compared to the Nd:YAG laser procedure during the first posttherapy week (p < 0.05). Regarding to cosmetic outcomes, no differences between techniques were observed for patient and professionals (p > 0.05). Significantly higher chair time was required for the scalpel technique than for the Nd:YAG laser therapy (p < 0.05). The Nd:YAG laser or the scalpel technique may be successfully used for the treatment of melanin gingival hyperpigmentation. However, the use of the Nd:YAG laser has presented advantages in terms of less discomfort/pain during the posttherapy period and a reduction of treatment chair time.

Photodynamic therapy in the treatment of class II furcation: a randomized controlled clinical trial.

AIM: To investigate the effect of photodynamic therapy (PDT) as adjunct to mechanical therapy in furcations. MATERIALS AND METHODS: A double-blind, parallel, randomized controlled clinical trial was conducted in subjects presenting class II furcations. The subjects were randomly allocated to a test (PDT; n = 16) or control group (non-activated laser/only photosensitizer; n = 21). At baseline, 3 and 6 months, clinical, microbiological and cytokine pattern evaluation was performed. Clinical attachment level was defined as the primary outcome variable. RESULTS: Clinical parameters improved after both therapies (p < 0.05) with no differences between groups at any time point (p > 0.05). At 6 months, real-time PCR evaluation showed a decrease in Porphyromonas gingivalis and Tannerella forsythia only in the PDT group (p < 0.05) with no inter-group differences. Regarding cytokines, IL-4 and IL-10 levels increased in both groups at 6 months. GM-CSF, IL-8, IL-1ß and IL-6 levels decreased only in the PDT group after 3 months (p < 0.05). At 3 months, inter-group analyses showed that GM-CSF, IFN-γ, IL-6 and IL-8 levels were lower in the PDT group. At 6 months, lower IL-1ß levels were also observed in the PDT group (p < 0.05). CONCLUSION: Photodynamic therapy did not promote clinical benefits for class II furcations; however, advantages in local levels of cytokines and a reduction in periodontopathogens were demonstrated.

Resveratrol decreases periodontal breakdown and modulates local levels of cytokines during periodontitis in rats.

BACKGROUND: Resveratrol (3,4',5-trihydroxystilbene) is a naturally occurring product found in numerous plants. Among its biologic properties, resveratrol may promote immunomodulatory effects on the host response. This study investigates the effect of continuous administration of resveratrol on the progression of experimental periodontitis in rats. METHODS: Periodontitis was induced in rats in one of the first molars chosen to receive a ligature. Animals were assigned to one of two groups: 1) daily administration of the placebo solution (control group) or 2) 10 mg/kg resveratrol (RESV group). The therapies were administered systemically for 30 days: for 19 days before periodontitis induction and then for another 11 days. Then, the specimens were processed for morphometric analysis of bone loss, and the gingival tissue surrounding the first molar was collected for quantification of interleukin (IL)-1ß, IL-4, and IL-17 using a multiplexing assay. RESULTS: Intergroup comparisons of the morphometric outcomes revealed higher bone loss values in ligated molars and unligated teeth in the control group than the RESV group (P <0.05). The immunoenzymatic assay of the gingival tissue showed a lower concentration of IL-17 in the RESV group than the control group (P <0.05), whereas no differences in the IL-1ß and IL-4 levels of the groups were observed (P >0.05). CONCLUSIONS: Continuous administration of resveratrol may decrease periodontal breakdown induced experimentally in rats. In addition, lower levels of IL-17 were found in the RESV group. Future studies are important to confirm the mechanism through which resveratrol exerts its effects.

Evaluation of the effects of buccal-palatal bone width on the incidence and height of the interproximal papilla between adjacent implants in esthetic areas.

BACKGROUND: The presence of interproximal papilla depends on the distance between the contact point to the bone crest, as well as the mesio-distal distance between implants or between implants and teeth. The aim of this study is to evaluate the effects of buccal-palatal bone width on the presence of the interproximal papilla between adjacent implants in esthetic areas of the mouth. METHODS: The presence or absence of the gingival papilla, distance from the base of the interproximal contact to the tip of the gingival papilla (black space), distance from the base of the interproximal contact to the alveolar crest (vertical distance), alveolar bone width (bone width) between adjacent implants as well as the spacing between the implants (horizontal distance), and soft-tissue biotype were assessed in 29 interimplant areas in the upper incisor, canine, and premolar regions of 18 patients. RESULTS: The papilla was always present when vertical distance was ≤5 mm (P ≤0.04) and frequently present when the horizontal distance was ≥4 mm (P = 0.04). The black space was smaller when the vertical distance was ≤5 mm (P ≤0.04) and when the horizontal distance was ≥4 mm (P = 0.76). Bone width and soft-tissue biotype did not influence the incidence of gingival papilla (P ≥0.41) and black space (P ≥0.15). CONCLUSION: Within the limits of this study, it can be concluded that bone width and tissue biotype do not have an effect on the incidence and height of papilla between adjacent implants in esthetic areas, and the incidence was greater when vertical distance was ≤5 mm or when horizontal distance was ≥4 mm.

The adjunctive effect of photodynamic therapy for residual pockets in single-rooted teeth: a randomized controlled clinical trial.

Residual pockets are challenging sites that require additional periodontal therapy. The aim of this study was to evaluate the effect of a single photodynamic therapy (PDT) as an adjunct to scaling and root planning (SRP) in residual pockets in single-rooted teeth. A blind, split-mouth, randomized controlled clinical trial was conducted in systemically healthy subjects presenting at least two residual pockets (probing pocket depth (PPD) ≥ 5 mm with bleeding on probing (BoP)) in single root teeth in supportive periodontal therapy. The selected sites were assigned to receive (1) PDT + SRP or (2) SRP. In sites treated by PDT as adjunctive to SRP, the laser system included a handheld battery-operated diode laser with a wavelength of 660 nm, a power output of 60 mW, and energy density of 129 J/cm(2), together with methylene blue as a photosensitizer (10 mg/ml). Clinical parameters were assessed at baseline and 3 months post-therapies. Clinical parameters improved significantly after both therapies (p < 0.05), whereas higher probing pocket depth reduction and clinical attachment level gain were observed in the PDT + SRP group at 3 months (p < 0.05). In addition, sites treated by the combined approach yielded a significant reduction in the number of sites with PPD <5 mm without BoP after 3 months compared to sites treated by conventional SRP alone (p < 0.05). PDT as an adjunctive to mechanical debridement demonstrated additional clinical benefits for residual pockets in single-rooted teeth and may be an alternative therapeutic strategy in supportive periodontal maintenance.

Root cementum modulates periodontal regeneration in Class III furcation defects treated by the guided tissue regeneration technique: a histometric study in dogs.

BACKGROUND: Because the possibility of root cementum preservation as an alternative approach for the treatment of periodontal disease has been demonstrated, this study aimed to histometrically evaluate the effect of root cementum on periodontal regeneration. METHODS: Bilateral Class III furcation defects were created in dogs, and each dog was randomly assigned to receive one of the following treatments: control (group A): scaling and root planing with the removal of root cementum; or test (group B): removal of soft microbial deposits by polishing the root surface with rubber cups and polishing paste, aiming at maximum cementum preservation. Guided tissue regeneration (GTR) was applied to both groups. RESULTS: Four months after treatment, a superior length of new cementum (3.59 +/- 1.67 mm versus 6.20 +/- 2.26 mm; P = 0.008) and new bone (1.86 +/- 1.76 mm versus 4.62 +/- 3.01 mm; P = 0.002) and less soft tissue along the root surface (2.77 +/- 0.79 mm versus 1.10 +/- 1.48 mm; P = 0.020) was observed for group B. Additionally, group B presented a larger area of new bone (P = 0.004) and a smaller area of soft tissue (P = 0.008). CONCLUSION: Within the limits of this study, root cementum may modulate the healing pattern obtained by guided tissue regeneration in Class III furcation defects.

Enamel matrix derivative and guided tissue regeneration in the treatment of dehiscence-type defects: a histomorphometric study in dogs.

BACKGROUND: The goal of this investigation was to histologically and histometrically evaluate the healing process of dehiscence-type defects treated by enamel matrix derivative (EMD) and/or guided tissue regeneration (GTR). METHODS: Seven mongrel dogs were used. Buccal osseous dehiscences were surgically created on the mesial roots of the mandibular third and fourth premolars. The defects were exposed to plaque accumulation for 3 months. After this period, the defects were randomly assigned to one of the treatments: open flap debridement (OFD), enamel matrix derivative (EMD), GTR with bioabsorbable membrane (GTR), and the combination of both procedures (EMD + GTR). After 4 months of healing, the dogs were sacrificed and the blocks were processed. The histometric parameters evaluated included gingival recession, epithelial length, connective tissue adaptation, new cementum, and new bone. RESULTS: A superior length of new cementum was observed in the sites treated by EMD (3.7 mm) and EMD + GTR (3.8 mm) in comparison with OFD (2.4 mm) (P < 0.05). No statistically significant differences were found in the remaining histometric parameters. CONCLUSIONS: Within the limits of this study, it can be concluded that EMD alone or in combination with GTR barriers may effectively promote new cementum formation. The combination of both therapies may not provide additional benefits.

Guided bone regeneration may be negatively influenced by nicotine administration: a histologic study in dogs.

BACKGROUND: A series of animal and in vitro data confirms that nicotine impairs bone healing, diminishes osteoblast function, and causes autogenous bone graft morbidity. Therefore, this study aimed to investigate the impact of nicotine on the healing of bone defects treated by the guided bone regeneration (GBR) principle. METHODS: Sixteen mongrel dogs were used. One defect was surgically created bilaterally and randomly assigned as an expanded polytetrafluoroethylene (ePTFE) membrane site or a non-membrane control site. The animals were randomly assigned to one of the following groups: group 1, placebo (n = 8) and group 2, subcutaneous administration of nicotine (2 mg/kg) twice daily (n = 8). After 4 months, the animals were sacrificed and the specimens routinely processed for semi-serial decalcified sections. The evaluated parameters were bone height, bone width, bone density, and bone area of newly formed bone. RESULTS: Intergroup analysis (Kruskal-Wallis) showed that membrane-protected defects in the placebo group demonstrated an increased bone area when compared to membrane-protected defects in the nicotine group and non-membrane sites, regardless of nicotine administration (P < 0.05). In addition, nicotine administration significantly affected bone density in membrane- and non-membrane-protected sites (P < 0.05). CONCLUSIONS: Within the limits of the present study, nicotine might affect, but not prevent, bone healing in defects treated by guided bone regeneration. The mechanisms of this effect should be investigated further.