Nitrite in paraffin-stimulated saliva correlates with blood nitrite.

Nitrite anion (NO2-) is a circulating nitric oxide (NO) metabolite considered an endothelial function marker. Nitrite can be produced from nitrate (NO3-) secreted from plasma into saliva. The nitrate reductase of oral bacteria converts salivary nitrate to nitrite, which is swallowed and absorbed into circulation. In this study, we aimed to examine the relevance between these species' salivary and blood levels. We collected three whole saliva samples (unstimulated, paraffin-stimulated, and post-chlorhexidine mouthwash stimulated saliva) and blood from 75 healthy volunteers. We measured the nitrite and nitrate by the chemiluminescence method. The nitrite levels in stimulated saliva and post-mouthwash stimulated saliva exhibited weak correlations with blood nitrite. There was no correlation between nitrite in unstimulated saliva with blood nitrite. The baseline platelet activity, determined as P-selectin expression, negatively correlated with nitrite in plasma and post-mouthwash stimulated saliva. The salivary nitrate in all saliva samples showed correlations with its plasma levels. We conclude that nitrite in stimulated saliva correlates with blood nitrite.

Platelet-rich plasma stimulated proliferation, migration, and attachment of cultured periodontal ligament cells.

OBJECTIVE: The aim of this study is to evaluate the effects of platelet-rich plasma (PRP) on the proliferation, migration, and attachment of cultured periodontal ligament (PDL) cells. MATERIALS AND METHODS: 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to assess number of PDL cells cultured in medium with or without PRP. Cell migration toward medium with or without PRP was assessed using the Boyden chamber. Cell attachment was assessed by counting cells on PRP or non-PRP coated dentin specimens. Group differences were analyzed using two-way ANOVA at 0.05 significance level. RESULTS: In the MTT and cell migration assay, the number of cells in 5% and 10% PRP-treated groups were significantly higher than that in the non-PRP-treated group (P < 0.05). In the attachment assay, the number of cells on the dentin specimens in 10% PRP-treated group was significantly higher than that in the non-PRP treated group (P < 0.05). CONCLUSION: PRP could stimulate proliferation, migration, and attachment of PDL cells.

Clinical comparison of the stain removal efficacy of two air polishing powders.

OBJECTIVES: Air polishing with sodium bicarbonate powders with a grain size of 40 µm is recommended for patient comfort. However, the efficacy of small grain size on stain removal has not been adequately studied. This study aimed to compare the stain removal efficacy of sodium bicarbonate powders with grain sizes of 65 and 40 µm and to evaluate patient acceptance and operator opinion after using both air polishing powders. MATERIALS AND METHODS: A double-blind, randomized, split-mouth study was conducted with 35 participants with moderate to heavy dental staining on both sides of the upper teeth. Removal of dental stains on the index teeth was performed using sodium bicarbonate powders with a grain size of either 65 or 40 µm. The time taken to completely remove all dental stains was recorded. After treatment, a questionnaire was used to evaluate patient acceptance and the operator's opinion. RESULTS: The average time for the removal of all stains by powder was 4.5 ± 3.6 min with a grain size of 65 µm and 4.4 ± 3.8 min with a grain size of 40 µm. The difference in the average time between the two groups was not significant (P = 0.461). The operator's opinions of the two powders were identical, and patient acceptance did not differ significantly between the two types of powders. CONCLUSIONS: The 40 µm sodium bicarbonate powder removed dental stains as efficiently as the 65-µm powder. Powder handling and patient acceptance were comparable between grain sizes of 65 and 40 µm.

Long-term outcome following regenerative periodontal treatment of intrabony defects.

This study aimed to evaluate the long-term outcome of the regenerative periodontal therapy of an intrabony defect in terms of tooth survival and clinical attachment level (CAL) stability. The association between failure and patient as well as tooth variables was assessed. Treatment records of the patients who received regenerative surgery and re-evaluation at 1-year post-surgery were screened. Patient and tooth variables, defect characteristics, and types of treatments were collected. Periodontal parameters were retrieved before regenerative surgery (baseline), 1-year post-surgery, and every visits of supportive periodontal treatment (SPT) until failure, including tooth loss or CAL loss ≥2 mm was found. In this study, treatment records from 89 patients were included. These patients continued SPT from 0.5-11.16 years. Of these patients, 92.1 % survived from tooth loss, while 61.8 % survived from CAL loss ≥2 mm compared to 1-year post-surgery. At the sites with residual pocket depth <5 mm, patients attending SPT >80 % had a significantly less percentage of teeth with CAL loss ≥2 mm compared to 1-year post-surgery than those attending SPT <80 %. However, at the sites with residual pocket depth ≥5 mm, no significant difference in the percentage of teeth with CAL loss ≥2 mm was found between patients attending SPT >80 % or <80 %. Smoking, patient's compliance, and residual pocket depth after regenerative surgery were significantly associated with tooth loss. However, these factors were not significantly associated with CAL loss compared to baseline or 1-year post-surgery.

Clinical effect of locally delivered gel containing green tea extract as an adjunct to non-surgical periodontal treatment.

UNLABELLED: Green tea catechins had an in vitro antibacterial effect against periodontopathic bacteria and were able to inhibit destruction of the periodontal tissue. In this study, we aimed to evaluate the effect of locally delivered gel containing green tea extract as an adjunct to non-surgical periodontal treatment. Forty-eight subjects who had teeth with probing pocket depth of 5-10 mm were randomly allocated into the test or control group. Probing pocket depth, clinical attachment level, gingival index (GI), bleeding on probing (BOP) and full mouth plaque score were measured at baseline. Subjects received oral hygiene instruction, single episode of scaling and root planing and subgingival application of the green tea gel (test group) or the placebo gel (control group). The gel was repeatedly applied at 1 and 2 weeks later. The parameters were recorded again at the 1st, 3rd and 6th month after the last gel application. The results showed that all parameters were improved in both groups compared to baseline. The test group exhibited significantly higher reduction in BOP at the 3rd month (p = 0.003) and significantly lower GI at the 1st month (p < 0.001) and 3rd month (p < 0.001) when compared with the control group. Thus, green tea gel could provide a superior benefit in reducing bleeding on probing and gingival inflammation when used as an adjunct to non-surgical periodontal treatment. ( TRIAL REGISTRATION: MU-IRB 2008/153.0511, ClinicalTrials.gov NCT00918060).