Systemic Chemical Desensitization of Peptidergic Sensory Neurons with Resiniferatoxin Inhibits Experimental Periodontitis

Background and objective: The immune system is an important player in the pathophysiology of periodontitis. The brain controls immune responses via neural and hormonal pathways, and brain-neuro-endocrine dysregulation may be a central determinant for pathogenesis. Our current knowledge also emphasizes the central role of sensory nerves. In line with this, we wanted to investigate how desensitization of peptidergic sensory neurons influences the progression of ligatureinduced periodontitis, and, furthermore, how selected cytokine and stress hormone responses to Gram-negative bacterial lipopolysaccharide (LPS) stimulation are affected. Material and methods: Resiniferatoxin (RTX; 50 μg/kg) or vehicle was injected subcutaneously on days 1, 2, and 3 in stress high responding and periodontitis-susceptible Fischer 344 rats. Periodontitis was induced 2 days thereafter. Progression of the disease was assessed after the ligatures had been in place for 20 days. Two h before decapitation all rats received LPS (150 μg/kg i.p.) to induce a robust immune and stress response. Results: Desensitization with RTX significantly reduced bone loss as measured by digital X-rays. LPS provoked a significantly higher increase in serum levels of the pro-inflammatory cytokine tumour necrosis factor (TNF)-, but lower serum levels of the anti-inflammatory cytokine interleukin (IL)-10 and the stress hormone corticosterone. Conclusions: In this model RTX-induced chemical desensitization of sensory peptidergic neurons attenuated ligatureinduced periodontitis and promoted a shift towards stronger pro-inflammatory cytokine and weaker stress hormone responses to LPS. The results may partly be explained by the attenuated transmission of immuno-inflammatory signals to the brain. In turn, this may weaken the anti-inflammatory brain-derived pathways

Patients’ perception of own efforts versus clinically observed outcomes of non-surgical periodontal therapy in a Norwegian population: an observational study

Background Most periodontal intervention studies have focused on biomedical qualities like change in pocket depth and clinical attachment levels. Very few studies have described patient response in terms of how patients' general lives are affected by disease, treatment, and communication with therapy providers. Thus the aim of the present study was to investigate patient response to systematic periodontal information, motivation and treatment strategy (primary aim) by comparing the patients’ perception of own efforts and results with those clinically registered in a trans-sectional, observational study (secondary aim). Methods One year after treatment of 184 patients, 152 completed a questionnaire covering aspects of received oral health information and instruction, expectations, communication with the therapeutic team, behavioral change, self-perceived outcomes and satisfaction. Results More than 90% of the patients were satisfied with the interaction with the specialist team. 98% were satisfied with the information and instruction they had been given. 84% said that the information had been necessary to make them change their behavior towards better oral hygiene. Pain and discomfort, as well as bleeding were reduced substantially from before to after treatment, and 28 patients reported to have stopped smoking. In all questions regarding well-being there were statistically significant changes towards positive impact following therapy. Conclusions Periodontal treatment, including customized information and education on the etiology and pathogenesis, prevention and treatment as well as maintenance of periodontal diseases resulted in a high degree of short- and long term compliance, and very good patient centered outcomes, which again had a positive impact on the patients’ satisfaction. The patient centered outcomes correlated mostly with the compared clinical endpoints. Trial registration ClinicalTrials.gov: NCT01318928

Maternal deprivation of Lewis rat pups increases the severity of experimental periodontitis in adulthood

Background and Objective: Early life adverse events may influence susceptibility/resistance to chronic inflammatory diseases later in life by permanently dysregulating brain-controlled immune-regulatory systems. We have investigated the impact of infant-mother separation during early postnatal life on the severity of experimental periodontitis, as well as systemic stress and immune responses, in adulthood. Material and Methods: Pups of periodontitis resistant Lewis rats were separated from their mothers for 3 h daily during postnatal days 2-14 (termed maternal deprivation; MD), separated for 15 min daily during the same time period (termed handling; HD), or left undisturbed. As adults, their behaviour was tested in a novel stressful situation, and ligature-induced periodontitis applied for 21 days. Two h before sacrifice all rats were exposed to a gram-negative bacterial lipopolysaccharide (LPS) challenge to induce a robust immune and stress response. Results: Compared to undisturbed controls, MD rats developed significantly more periodontal bone loss as adults, whereas HD rats showed a tendency to less disease. MD and HD rats exhibited depression-like behaviour in a novel open field test, while MD rats showed higher glucocorticoid receptor (Gr) expression in the hippocampus, and HD rats had altered methylation of genes involved in the expression of hippocampal Gr. LPS provoked a significantly lower increase in circulating levels of the cytokine TGF-1β in MD and HD rats, but there were no significant differences in levels of the stress hormone corticosterone. Conclusion: Stressful environmental exposures in very early life may alter immune responses in a manner that influences susceptibility/resistance to periodontitis

Effect of instruction and motivation in the use of electric and manual toothbrushes in periodontal patients: a comparative study

The aim of the present study was to evaluate the efficacy of manual and electric toothbrushes in plaque control in periodontal patients after proper instructions. Thirty six periodontal patients (mean age of 49 years, 21 females and 15 males) were included and completed the study (100% compliance). A single-blinded, randomized, controlled, cross-over clinical design was adopted, with the patients using during 2 periods of 14 days each the manual and/or electric toothbrush. Four subgroups of 9 individuals were studied: A1 - used manual toothbrush in both experimental periods; A2 - used the manual toothbrush during the first period and the electrical toothbrush during the second period; B1 - used electrical toothbrush during both periods; B2 - used the electrical toothbrush in the first period and the manual one in the second period. Brushing was performed during 14 days and at day 14 and 28 it was performed in the clinic, and timing of brushing was recorded without patients being aware. The Plaque Index (Silness, Löe, 1964) was used. Intra-group comparisons were performed by paired t-test and inter-group comparisons by independent sample t-test, with an alpha level of 0.05. The results showed no difference between the tested brushes neither for plaque nor for timing. However, re-instruction was detected as an important factor, since for all groups the second period, after reinstruction, showed lower plaque scores. It is concluded that professional advice and instruction and re-instruction seem more important in order to obtain good plaque control than the choice of toothbrush in subjects with periodontal disease