Scaling and root planing with and without periodontal flap surgery

. Complete removal of calculus is a primary part of achieving a “biologically acceptable” tooth surface in the treatment of periodontitis. Rabbani et al. reported that a single episode of scaling did not completely remove subgingival calculus and that the deeper the periodontal pocket, the less complete the calculus removal. The purpose of the present study was to evaluate the effectiveness of scaling relative to calculus removal following reflection of a periodontal flap. Each of 21 patients who required multiple extractions had 2 teeth scaled, 2 teeth scaled following the reflection of a periodontal flap, and 2 teeth serve as controls. Local anesthesia was used. Following extraction, the % of subgingival tooth surfaces free of calculus was determined using the method described by Rabbani with a stereomicroscope. Results showed that while scaling only (SO) and scaling with a flap (SF) increased the % of root surface without calculus, scaling following the reflection of a flap aided calculus removal in pockets 4 mm and deeper. Comparison of SO versus SF at various pocket depths for % of tooth surfaces completely free of calculus showed 1 to 3 mm pockets to be 86% versus 86%, 4 to 6 mm pockets to be 43% versus 76% and >6 mm pockets to be 32% versus 50%. The extent of residual calculus was directly related to pocket depth, was greater following scaling only, and was greatest at the CEJ or in association with grooves, fossae or furcations. No differences were noted between anterior and posterior teeth or between different tooth surfaces.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73823/1/j.1600-051X.1986.tb01461.x.pd

Extravascular lung water assessed by transpulmonary single thermodilution and postmortem gravimetry in sheep

INTRODUCTION: Acute lung injury is associated with accumulation of extravascular lung water (EVLW). The aim of the present study was to compare two methods for quantification of EVLW: transpulmonary single thermodilution (EVLW(ST)) and postmortem gravimetric (EVLW(G)). METHODS: Eighteen instrumented and awake sheep were randomly assigned to one of three groups. All groups received Ringer's lactate (5 ml/kg per hour intravenously). To induce lung injury of different severities, sheep received Escherichia coli lipopolysaccharide 15 ng/kg per min intravenously for 6 hours (n = 7) or oleic acid 0.06 ml/kg intravenously over 30 min (n = 7). A third group (n = 4) was subjected to sham operation. Haemodynamic variables, including EVLW(ST), were measured using a PiCCOplus monitor (Pulsion Medical Systems, Munich, Germany), and the last measurement of EVLW(ST )was compared with EVLW(G). RESULTS: At the end of experiment, values for EVLW(ST )(mean ± standard error) were 8.9 ± 0.6, 11.8 ± 1.0 and 18.2 ± 0.9 ml/kg in the sham-operated, lipopolysaccharide and oleic acid groups, respectively (P < 0.05). The corresponding values for EVLWI(G )were 6.2 ± 0.3, 7.1 ± 0.6 and 11.8 ± 0.7 ml/kg (P < 0.05). Ranges of EVLWI(ST )and EVLWI(G )values were 7.5–21.0 and 4.9–14.5 ml/kg. Regression analysis between in vivo EVLW(ST )and postmortem EVLW(G )yielded the following relation: EVLW(ST )= 1.30 × EVLW(G )+ 2.32 (n = 18, r = 0.85, P < 0.0001). The mean bias ± 2 standard deviations between EVLW(ST )and EVLW(G )was 4.9 ± 5.1 ml/kg (P < 0.001). CONCLUSION: In sheep, EVLW determined using transpulmonary single thermodilution correlates closely with gravimetric measurements over a wide range of changes. However, transpulmonary single thermodilution overestimates EVLW as compared with postmortem gravimetry

Recombinant human activated protein C ameliorates oleic acid-induced lung injury in awake sheep

Introduction: Acute lung injury (ALI) may arise both after sepsis and non-septic inflammatory conditions and is often associated with the release of fatty acids, including oleic acid (OA). Infusion of OA has been used extensively to mimic ALI. Recent research has revealed that intravenously administered recombinant human activated protein C (rhAPC) is able to counteract ALI. Our aim was to find out whether rhAPC dampens OA-induced ALI in sheep. Methods: Twenty-two yearling sheep underwent instrumentation. After 2 days of recovery, animals were randomly assigned to one of three groups: (a) an OA+rhAPC group (n = 8) receiving OA 0.06 mL/kg infused over the course of 30 minutes in parallel with an intravenous infusion of rhAPC 24 mg/kg per hour over the course of 2 hours, (b) an OA group (n = 8) receiving OA as above, or (c) a sham-operated group (n = 6). After 2 hours, sheep were sacrificed. Hemodynamics was assessed by catheters in the pulmonary artery and the aorta, and extravascular lung water index (EVLWI) was determined with the single transpulmonary thermodilution technique. Gas exchange was evaluated at baseline and at cessation of the experiment. Data were analyzed by analysis of variance; a P value of less than 0.05 was regarded as statistically significant. Results: OA induced profound hypoxemia, increased right atrial and pulmonary artery pressures and EVLWI markedly, and decreased cardiac index. rhAPC counteracted the OA-induced changes in EVLWI and arterial oxygenation and reduced the OA-induced increments in right atrial and pulmonary artery pressures. Conclusions: In ovine OA-induced lung injury, rhAPC dampens the increase in pulmonary artery pressure and counteracts the development of lung edema and the derangement of arterial oxygenation

Inhaled aerosolised recombinant human activated protein C ameliorates endotoxin-induced lung injury in anaesthetised sheep

Introduction We recently demonstrated that intravenously infused recombinant human activated protein C (APC) attenuates ovine lipopolysaccharide (LPS)-induced lung injury. In this study, our aim was to find out whether treatment with inhaled aerosolised APC (inhAPC) prevents formation of increased lung densities and oedema and derangement of oxygenation during exposure to LPS. Methods: Sheep were anaesthetised during placement of intravascular introducers. After one to four days of recovery from instrumentation, the animals were re-anaesthetised, endotracheally intubated and mechanically ventilated throughout a six-hour experiment where the sheep underwent quantitative lung computed tomography. Sheep were randomly assigned to one of three groups: a sham-operated group (n = 8) receiving inhaled aerosolised saline from two hours after the start of the experiment; a LPS group (n = 8) receiving an intravenous infusion of LPS 20 ng/kg per hour and, after two hours, inhaled aerosolised saline over the next four hours; a LPS+inhAPC group (n = 8) receiving an intravenous infusion of LPS 20 ng/kg per hour and, after two hours, aerosolised APC 48 µg/kg per hour inhaled throughout the experiment. Data were analysed with analysis of variance; P less than 0.05 was regarded as significant. Results: An infusion of LPS was associated with a reduction of well-aerated lung volume and a rapid fall in arterial oxygenation that were both significantly antagonised by inhaled APC. Pulmonary vascular pressures and extravascular lung water index increased significantly during exposure to LPS, but inhaled APC had no effect on these changes. Conclusions: Inhalation of aerosolised APC attenuates LPSinduced lung injury in sheep by preventing a decline in the volume of aerated lung tissue and improving oxygenation

Recombinant human activated protein C attenuates endotoxin-induced lung injury in awake sheep

Introduction: Acute lung injury often complicates severe sepsis. In Gram-negative sepsis, bacterial endotoxin activates both coagulation and inflammation. Enhanced lung vascular pressures and permeability, increased extravascular lung water content and deteriorated gas exchange characterize ovine endotoxin-induced lung injury, a frequently used model of acute lung injury. Recombinant human activated protein C (rhAPC), with its anticoagulant, anti-inflammatory, fibrinolytic and antiapoptotic effects, reportedly reduces the respiratordependent days and the mortality of patients with severe sepsis. We speculate whether rhAPC antagonizes endotoxin-induced lung injury in sheep. Methods: Two groups of sheep were exposed to Escherichia coli endotoxin (lipopolysaccharide) 15 ng/kg/minute intravenously from 0 to 24 hours; one group received only lipopolysaccharide throughout (n = 8), and the other group received lipopolysaccharide in combination with rhAPC 24 μg/ kg/hour from 4 to 24 hours (n = 9). In addition, one group received rhAPC as above as the only intervention (n = 4), and four sham-operated sheep were used for determination of the α and ε isoforms of protein kinase C in pulmonary tissue. Data were assessed by one-way analysis of variance for repeated measurements. Biochemical data were analyzed using Student's t test, or using the Mann–Whitney U test when appropriate. Results: Infusion of endotoxin caused lung injury, manifested by increments in pulmonary artery pressure, in pulmonary microocclusion pressure, in pulmonary vascular downstream resistance, in pulmonary vascular permeability index, in extravascular lung water index and in deterioration of oxygenation that were all attenuated by infusion of rhAPC. Endotoxemia led to changes in inflammation and coagulation, including pulmonary neutrophil accumulation paralleled by increased TNFα and decreased protein C and fibrinogen in animal plasma, which all improved following infusion of rhAPC. Moreover, rhAPC prevented the translocation of protein kinase C α and ε isoforms from the cytosolic fraction of lung tissue extracts. Conclusion: In awake sheep, rhAPC alleviates endotoxininduced lung injury – as characterized by improvements of oxygenation, coagulation and inflammation, as well as by reversal of pulmonary hemodynamic and volumetric changes

Revascularization of the Periodontium After Tooth Grafting in Monkeys

In replanted and homo transplanted teeth a vascular network developed in the blood clot between the two parts of the torn periodontium, which allowed the grafted ligament to regain its vascularity. When dentoalveolar ankylosis developed, the periodontal vasculature was split into a number of vascular clusters. In homotransplants, a definite cellular immunologic response by the host was absent. An acrylic radicular obturator was used.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67229/2/10.1177_00220345710500025101.pd

Effects of Acrylic Restorations on the Periodontium of Monkeys

Replanted teeth that had an acrylic restoration in the middle third of their roots were studied from three days to six months after grafting. The study revealed that the acrylic obturator elicited epithelial proliferation, fibrous encapsulation, moderate chronic inflammation, and adjacent alveolar bone loss.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68162/2/10.1177_00220345720510052201.pd

The effects on chronic periodontitis of a subgingivally-placed redox agent in a slow release device

Adjunctive chemical agents can reduce the need for meticulous plaque control. The aim of this investigation was to evaluate the periodontal treatment potential of subgingival application of the redox agent methylene blue in a slow release device. This randomized, single-blind, split-mouth study included 18 patients aged 35- 57 years, with chronic adult periodontitis, pocketing of at least 5mm and radiographic evidence of regular bone loss. All experimental sites received subgingival debridement at day 0. Test sites received 32% w/w methylene blue in the slow release device at days 0 and 28. Clinical examination and microbiological sampling were performed at days 0, 7, 28, 56 and 84. Clinical improvements were seen in both groups, but test sites showed consistently greater improvements, some of which were statistically significant (as determined by between-group comparisons utilising SNDs). Significant between-group differences in relation to baseline levels were seen in bleeding index at days 7 and 56, in probable pocket depth at day 56 and for the Perioscan BANA test at day 7. This pilot study thus showed that adjunctive methylene blue in a slow-release device can produce greater clinical and microbiological improvements than subgingival debridement alone.peer-reviewe

Presence of Helicobacter pylori in betel chewers and non betel chewers with and without oral cancers

<p>Abstract</p> <p>Background</p> <p>Betel chewing has been shown to predispose to periodontal disease and oral cancer. Studies show that people with gum disease are more likely to test positive for <it>Helicobacter pylori (H. pylori)</it>. It is not known if the lesions produced by betel quid and the resulting, chemical changes predispose to colonization by <it>H. pylori</it>. Further the role of this organism in oral cancer is not known. Our objective was to determine the presence of <it>H. pylori </it>in oral lesions of thirty oral cancer patients and to determine the presence of IgG antibodies to <it>H. pylori </it>in oral cancer patients who are betel chewers and non betel chewers, healthy betel chewers and healthy non-betel chewers and to compare the presence of <it>H</it>. <it>pylori </it>in these four groups. This case control study was conducted at the Cancer Institute Maharagama and the Department of Microbiology, Faculty of Medical Sciences, University of Sri Jayewardenepura.</p> <p>Methods</p> <p>One hundred and seventy three subjects, of whom fifty three were patients presenting with oral cancer to the Cancer Institute Maharagama, sixty healthy betel chewers and sixty healthy non-betel chewers from the Religious and Welfare Service Centre Maharagama were tested for <it>H. pylori </it>by serology. Thirty oral biopsies from oral cancer patients were cultured under microaerophilic condition to isolate <it>H. pylori</it>. The statistic used was Chi-square test.</p> <p>Results</p> <p>Of the fifty-three oral cancer patients, forty-four were betel chewers. Among the 53 oral cancer patients examined, ten of forty-four (10/44 = 22.7%) patients who are betel chewers and four of nine (4/9 = 44.4%) patients who are non-betel chewers were detected positive for IgG antibody against <it>H. pylori</it>. In the healthy group (betel chewers and non betel chewers) ten (16.7%) of the healthy betel chewers tested positive for <it>H. pylori </it>by serology. None of the healthy non-betel chewers tested positive for <it>H. pylori</it></p> <p>Fourteen [26.4%] of oral cancer patients tested positive for <it>H. pylori </it>by serology, of which two were also culture positive (Only thirty samples were cultured). The presence of <it>H. pylori </it>in betel chewers (with or without cancer) compared to non-betel chewers was statistically significant. (Chi-square test p < 0.05) The use of tobacco and areca nut in betel chewers was significant with the presence of <it>H. pylori </it>(p < 0.05).</p> <p>Conclusion</p> <p>There is a significant higher proportion of <it>H. pylori </it>in betel chewers compared to non-betel chewers but not between oral cancer patients compared to patients without oral cancer. Hence Betel chewing may predispose to colonisation with <it>H. pylori </it>in the digestive tract through swallowing the quid or during betel chewing.</p

Fasudil improves survival and promotes skeletal muscle development in a mouse model of spinal muscular atrophy

<p>Abstract</p> <p>Background</p> <p>Spinal muscular atrophy (SMA) is the leading genetic cause of infant death. It is caused by mutations/deletions of the survival motor neuron 1 (<it>SMN1</it>) gene and is typified by the loss of spinal cord motor neurons, muscular atrophy, and in severe cases, death. The SMN protein is ubiquitously expressed and various cellular- and tissue-specific functions have been investigated to explain the specific motor neuron loss in SMA. We have previously shown that the RhoA/Rho kinase (ROCK) pathway is misregulated in cellular and animal SMA models, and that inhibition of ROCK with the chemical Y-27632 significantly increased the lifespan of a mouse model of SMA. In the present study, we evaluated the therapeutic potential of the clinically approved ROCK inhibitor fasudil.</p> <p>Methods</p> <p>Fasudil was administered by oral gavage from post-natal day 3 to 21 at a concentration of 30 mg/kg twice daily. The effects of fasudil on lifespan and SMA pathological hallmarks of the SMA mice were assessed and compared to vehicle-treated mice. For the Kaplan-Meier survival analysis, the log-rank test was used and survival curves were considered significantly different at <it>P </it>< 0.05. For the remaining analyses, the Student's two-tail <it>t </it>test for paired variables and one-way analysis of variance (ANOVA) were used to test for differences between samples and data were considered significantly different at <it>P </it>< 0.05.</p> <p>Results</p> <p>Fasudil significantly improves survival of SMA mice. This dramatic phenotypic improvement is not mediated by an up-regulation of Smn protein or via preservation of motor neurons. However, fasudil administration results in a significant increase in muscle fiber and postsynaptic endplate size, and restores normal expression of markers of skeletal muscle development, suggesting that the beneficial effects of fasudil could be muscle-specific.</p> <p>Conclusions</p> <p>Our work underscores the importance of muscle as a therapeutic target in SMA and highlights the beneficial potential of ROCK inhibitors as a therapeutic strategy for SMA and for other degenerative diseases characterized by muscular atrophy and postsynaptic immaturity.</p