Relationship between the formation of volatile sulfur compounds (VSC) and the severity of the periodontal disease: a pilot study.

This aim of this study was to evaluate the relationship between the formation of volatile sulfur compounds (VSC) and the severity of different kinds of periodontal disease. Twenty patients suffering from biofilm-related periodontal diseases and a control group of ten healthy individuals were selected. The patients were divided according to their periodontal diagnoses: marginal gingivitis (MG/n = 10) and chronic periodontitis (CP/n = 10). The patients received non-surgical therapy that consisted of motivation, scaling and root planing. Two experimental periods were used: T1 = baseline and T2 = final evaluation after three months. The data analysis showed that CP group had a significant reduction (p < 0.05) in probing depth (PD) and clinical attachment level (CAL), and group MG presented a reduction in GI (p < 0.05). There was a significant reduction (p < 0.05) in the aspartate aminotransferase (AST), N-a-benzoyl-DL-arginine-p-nitroanilide (BAPNA) and VSC levels in both MG and CP groups, although the deeper residual pockets led to higher AST and VSC levels in the CP group. Within the limits of the present pilot study, it can be concluded that the non-surgical therapy may influence VSC formation in a manner dependent on periodontal disease severity.

Regulation of cementoblast function by P. gingivalis lipopolysaccharide via TLR2.

Although cementoblasts express Toll-like receptors (TLR)-2 and -4, little is known regarding the possible participation of cementoblasts in the inflammatory response. We investigated the effects of Porphyromonas gingivalis lipopolysaccharide (LPS), tetra- and penta-acylated lipid A species (designated PgLPS(1435/1449) and PgLPS(1690), respectively), on gene expression of osteoclastogenesis-associated molecules in murine cementoblasts. Real-time quantitative RT-PCR analysis revealed that receptor activator of NF-kappaB ligand (RANKL), interleukin-6, Regulated on activation, normal T-cell expressed, and secreted (RANTES), macrophage inflammatory protein-1alpha, and monocyte chemoattractant protein-1 were rapidly and dramatically induced upon stimulation with PgLPS(1690), but only slightly induced with PgLPS(1435/1449). Osteoprotegerin, which was expressed constitutively, was not altered significantly. ELISA demonstrated synthesis of corresponding proteins. PgLPS(1690) significantly induced transcripts for NF-kappaB, and this activation was inhibited by pre-treatment with anti-TLR-2 but not with TLR-4 antibodies. These results suggest that cementoblasts participate in the recruitment of osteoclastic precursor cells by up-regulation of chemokines/cytokines.

Impact of mouthrinses on morning bad breath in healthy subjects.

BACKGROUND: During sleep, a proliferation of oral bacteria is responsible for the release of offending gases in morning breath even in healthy people. Thus, the aim of this study was to evaluate the bad breath-inhibiting effect of four commercially available mouthrinses (0.03% triclosan, 0.12% chlorhexidine gluconate, 0.05% cetylpyridinium chloride and essential oils) on morning breath when compared with a positive and a negative control. METHOD: A six-step double-blind, crossover, randomised study was conducted in 12 dental students with healthy periodontium, who refrained from mechanical plaque control during a 4-day period. The subjects were instructed to rinse twice daily with the assigned product during each period. Fifteen-day washout intervals were used. Before professional plaque and tongue coating removal (baseline), the morning breath was scored through volatile sulphur compounds (VSCs) level measured by a sulphide monitor. After 4 days, VSCs and plaque index (PI) were recorded. RESULTS: Even in the absence of mechanical plaque control, there was a decrease in VSC level with the use of all mouthrinses, with the exception of an increase with the use of the negative control. The VSC formation was inhibited in descending order, by positive control (0.2% chlorhexidine), 0.12% chlorhexidine, triclosan and essential oils and cetylpyridinium chloride. Plaque formation was inhibited by chlorhexidine mouthrinses and essential oils. CONCLUSIONS: These findings suggest that mouthrinses can reduce morning bad breath, and that such a reduction is not attributable only to the reduction of supragingival plaque formation.

Effect of triclosan dentifrices on mouth volatile sulphur compounds and dental plaque trypsin-like activity during experimental gingivitis development.

BACKGROUND: The objective of this study was to evaluate the effect of three commercial anti-plaque dentifrices containing 0.3% triclosan + 2% pvm/ma (Colgate Total), 0.3% triclosan + 0.75% Zn (Signal Global) and 0.3% triclosan + 5% PPi (Crest Complete) in comparison with an experimental dentifrice (0.3% triclosan + 2% pvm/ma + 0.75% Zn + 4% PPi) and a control dentifrice without anti-plaque agents on trypsin-like activity in dental plaque (detected by the hydrolysis of [Na-Benzoyl-DL-Anginine p-Nitroanilide (BAPNA)] and volatile sulphur compounds (VSCs) in mouth air during experimental gingivitis development. METHOD: A 5-step double blind, crossover experimental gingivitis study was conducted on 19 volunteers during a 21-day period. The volunteers refrained from brushing an experimental quadrant of teeth. The dentifrices were applied to those teeth via toothshield three times per day; simultaneously they brushed the other teeth with the same dentifrice. After each period, VSCs in mouth air and BAPNA hydrolysis by dental plaque accumulated in the experimental quadrant were determined. RESULTS: There was an increase (p < 0.05) in VSCs in mouth air when experimental gingivitis was induced in only one quadrant of teeth. None of the dentifrices was able to avoid the increase of VSCs during the experimental gingivitis development. The majority of the antiplaque dentifrices evaluated reduced the increase of VSC formation in comparison with the control (p < 0.05). There was no relationship between the ability of the dentifrices in reducing VSC formation and the inhibition of trypsin-like activity in dental plaque. CONCLUSIONS: Anti-plaque dentifrices reduce the increase of VSCs that occurs during the development of experimental gingivitis.

The effect of an immunosuppressive therapy and its withdrawal on bone healing around titanium implants. A histometric study in rabbits.

BACKGROUND: Immunosuppressive agents have been recognized as a factor affecting bone metabolism. We investigated the consequences of the administration and withdrawal of cyclosporin A/nifedipine on bone around titanium implants to observe whether these changes occur and if they are reversible. METHODS: Twenty-eight New Zealand rabbits were included in the study. Following anesthesia, the tibiae surface was exposed, and 2 screw-shaped implants 7.0 mm in length and 3.75 mm in diameter were placed bilaterally. The animals were randomly assigned to 1 of 4 experimental groups and received daily subcutaneous injections for 14 days: groups A and C were injected with vehicle while groups B and D received cyclosporin A (10 mg/kg) plus nifedipine (0.5 mg/kg). Groups A and B were sacrificed 14 days and groups C and D 42 days postoperatively. The degree of bone contact with the implant surface and the bone area within the limits of the threads of the implant were measured. RESULTS: Intergroup analysis revealed no significant difference (P > 0.05) in the degree of bone contact with the implant surface between the control and test groups on days 14 and 42. In contrast, the treated animals demonstrated a significant (P < 0.05) decrease in the bone area within the limits of the threads of the implant in both periods. CONCLUSIONS: The data of the present study suggest that the use of cyclosporin A/nifedipine may influence bone healing around titanium implants. This observation may have important clinical implications.

[Need of periodontal treatment evaluated with CPITN and its relation to the quality of the cervical margin of restorations]. / Necessidade de tratamento periodontal avaliada pelo CPITN e sua relação com a qualidade de acabamento cervical das restaurações.

Irregularities of the cervical margin of restorations facilitate the retention of bacterial plaque, hindering plaque control through the habitual procedures of oral hygiene and favoring the development of periodontal disease. The aim of this study was to evaluate the periodontal condition and treatment needs (applying CPITN) in relation to the cervical margin of dental restorations. Three hundred and sixty-seven teeth with class II and V cavities restored with amalgam, class III cavities restored with composite resin, cast metal restorations and unitary prostheses were examined. With a WHO periodontal probe, the position of the cervical margins of restorations was verified (supragingival, subgingival or at the gingival margin level); the presence of defects (lack or excess of restoring material) and the presence of score 2 of CPITN were also assessed. After the analysis of the data, it was possible to conclude that: 1) supragingival margins offered the best marginal adaptation and the lowest frequency of score 2; 2) both the lack and the excess of restoring material favor the development of score 2, despite the utilized material and 3) in subgingival margins, incorrect marginal adaptation was the most frequent event, mainly due to excess of restoring material, and in these cases there was higher frequency of score 2 of CPITN.

Histometric evaluation of the effect of nicotine administration on periodontal breakdown: an in vivo study.

The present study investigated the effect of nicotine administration on periodontal breakdown resulting from ligature-induced periodontitis in rats. Twenty adult male Wistar rats were used. After anesthesia, a mandibular first molar was randomly assigned to receive a cotton ligature in the sulcular area while the contralateral tooth was left unligated. The animals were randomly assigned to one of the following treatments. of daily intraperitoneal injections: A - saline solution, B -0.37 mg of nicotine kg, C -0.57 mg of nicotine kg and D -0.73 mg of nicotine/kg. Thirty days later, the animals were sacrificed and the specimens routinely processed for serial decalcified sections. Statistical analysis (ANOVA) revealed greater bone loss (p<0.05) in the ligated teeth of animals which received nicotine (groups B/C D) than in the ligated teeth of animals which received saline solution (group A). In addition, a dose-dependent response was observed among the nicotine groups. A negative effect of nicotine was observed in the unligated teeth of the experimental groups (p<0.05). Therefore, daily administration of nicotine enhanced, in a dose-dependent manner, the effects of local factors in producing periodontal breakdown. Furthermore, the nicotine seemed to have a direct deleterious effect on the periodontal tissues.

Treatment of ligature-induced peri-implantitis defects by regenerative procedures. Part II: A histometric study in dogs.

The purpose of this study was to evaluate, by histometric analysis, re-osseointegration following treatment of ligature-induced peri-implantitis in dogs. Five dogs were used in this study. Their mandibular premolars (P2, P3 and P4) were first removed. After 3 additional months of healing, two titanium implants were placed on each side of the mandible. After 3 months, the abutment connection was performed and experimental peri-implantitis was induced by placing cotton ligatures in a submarginal position. Ligatures and abutments were removed after one month and the peri-implant bone defects were randomly assigned to one of the treatments: debridement, debridement plus guided-bone regeneration, debridement plus mineralized-bone graft, and debridement plus guided-bone regeneration associated with mineralized-bone graft. Five months post-treatment, the degree of bone contact with the implant surface and the bone area within the threads were measured in 12 threads, the 6 most coronal at each side of each implant. One-way analysis of variance did not reveal statistically significant differences between the treatment modalities (p > 0.05). Within the limits of the present study, it can be concluded that there is a limited possibility of re-osseointegration around implant surfaces previously exposed by ligature-induced peri-implantitis.

The influence of nicotine on the bone loss rate in ligature-induced periodontitis. A histometric study in rats.

BACKGROUND: The present study investigated the possible influence of nicotine on the bone loss rate in the furcation region due to ligature-induced periodontitis in rats. METHODS: Twenty adult male Wistar rats were included. After anesthesia, the tooth was randomly assigned to receive the cotton ligature in the sulcular area, while the contralateral tooth was left unligated. The animals were randomly assigned to one of the following treatments, including daily intraperitoneal injections: group A, 2 microl/g body weight of saline solution; group B, 2 microl/g body weight of a nicotine solution with 0.13 microl of nicotine/ml of saline solution; group C, 2 microl/g body weight of a nicotine solution with 0.19 microl of nicotine/ml of saline solution; and group D, 2 microl/g body weight of a nicotine solution with 0.26 microl of nicotine/ml of saline solution. Thirty days later, the animals were sacrificed and the specimens routinely processed for serial decalcified sections. RESULTS: Intergroup analysis revealed greater bone loss in the ligated teeth of group B (1.01 +/- 0.61 mm2), group C (1.14 +/- 0.72 mm2), and group D (1.36 +/- 0.60 mm2) when compared with group A (0.64 +/- 0.62 mm2) (P <0.01). However, no statistically significant differences in bone loss were found among groups B, C, and D. In addition, no bone loss was observed for unligated teeth (P>0.01). CONCLUSIONS: Within the limits of the present study, nicotine enhanced the effects of the local components of periodontal disease in a non-dose-dependent way; nevertheless, the administration of nicotine did not produce periodontal bone loss by itself.

Effect of 3 dentifrices containing triclosan and various additives. An experimental gingivitis study.

BACKGROUND: The antiplaque and antigingivitis effect of 3 dentifrices was evaluated using the 21-day partial-mouth experimental model of gingivitis. METHOD: 25 volunteers took part in this cross-over, double-blind study, carried out in 4 phases of 21 days each. For each phase of the study, a toothshield of the IV quadrant was constructed for each volunteer. 2 antiplaque dentifrices from the market, one containing triclosan + pvm/ma and the other triclosan + Zn, were compared with an experimental formulation and its placebo. The experimental dentifrice contained triclosan + pvm/ma + Zn + PPi and the placebo (control) did not contain these substances. The subjects were stratified according to their whole-mouth baseline plaque (PI), gingivitis (GI) and bleeding (BI) index scores, and then randomly assigned to 1 of 4 dentifrices. During each phase, while the volunteers brushed their teeth with one of the dentifrices, the IV quadrant was protected by the toothshield filled with the dentifrice used. After each phase, dental plaque, gingivitis and bleeding indices were determined. RESULTS: The results showed that only the formulation containing triclosan + pvm/ma + Zn + PPi was able to reduce PI (28.8%), GI (35.9%) and BI (30.4%) in comparison with controls (p<0.05). CONCLUSIONS: The data suggest that a dentifrice containing the combination of triclosan + pvm/ma + Zn + PPi should be formulated for dental plaque control.