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Query: UMLS:C0031099 (periodontitis)
 12,489 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Apical periodontitis, an inflammatory process around the apex of a tooth root, is primarily a sequel to microbial infection of the pulp space. The microbial flora is composed of a restricted group of the total oral flora, selected by environmental pressures of anaerobiosis, nutrition and competition with other species and inhabits the root canal as a biofilm of coaggregated communities in an extracellular matrix. The untreated infected canal is generally composed of a polymicrobial mix with approximately equal proportions of Gram-positive and Gram-negative species, dominated by obligate anaerobes. The type of microbial flora in the root-filled tooth with persistent apical periodontitis has very different characteristics. These infections are characterized by one or just a few species, predominantly Gram-positive micro-organisms with an equal distribution of facultative and obligate anaerobes. Enterococcus faecalis has been a conspicuous finding in most studies. Because the primary aetiological problem is infection, endodontic treatment is directed at control and elimination of the root canal flora by working in a sterile way. Based on current knowledge, the best available method for obtaining clean, microbe-free root canals is by instrumentation with antimicrobial irrigation reinforced by an intracanal dressing with calcium hydroxide.
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PMID:A big role for the very small--understanding the endodontic microbial flora. 1754 61

This clinical study was conducted to assess the bacterial reduction after chemomechanical preparation with 2.5% NaOCl as an irrigant and the additive antibacterial effect of intracanal dressing with calcium hydroxide. According to stringent inclusion criteria, 11 teeth with primary intraradicular infections and chronic apical periodontitis were selected and monitored in the study. Bacterial samples were taken at the baseline (before treatment) (S1), after chemomechanical preparation with 2.5% NaOCl as an irrigant (S2), and after a 7-day dressing with a calcium hydroxide paste in glycerin (S3). Cultivable bacteria recovered from infected root canals at the 3 stages were counted and identified by means of 16S rRNA gene sequencing analysis. At S1, all canals were positive for bacteria, with the mean number of 2.8 taxa per canal (range, 1-6). At S2, 5 cases (45.5%) still harbored cultivable bacteria, with 1 or 2 species per canal. At S3, bacteria were cultured from 2 cases (18.2%), with 1 species per positive case. There was no indication that any specific bacterial taxon was more resistant to treatment. A significant reduction in bacterial counts was observed between S1 and S2, and S1 and S3. However, no statistically significant difference was observed for comparisons involving S2 and S3 samples with regard to the number of cases yielding negative cultures (P = .18) or quantitative bacterial reduction (P = .19). It was concluded that the whole antibacterial protocol used in this study significantly reduced the number of bacteria in the canal and rendered most canals free of cultivable bacteria.
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PMID:Effects of chemomechanical preparation with 2.5% sodium hypochlorite and intracanal medication with calcium hydroxide on cultivable bacteria in infected root canals. 1780 15

The choice of one-visit versus two-visit root canal therapy for necrotic teeth with apical periodontitis is a source of current debate. The primary objective of this randomized controlled clinical trial was to compare radiographic evidence of periapical healing after root canal therapy completed in one visit or two visits with an interim calcium hydroxide/chlorhexidine paste dressing. Ninety-seven patients met the inclusion criteria and consented to participate in this study. Patients were randomly assigned to either the one-visit or two-visit group, and root canal therapy was performed with a standardized protocol. Patients in the two-visit group received an intracanal dressing of calcium hydroxide/chlorhexidine paste. Sixty-three patients, 33 in the one-visit group and 30 in the two-visit group, were evaluated at 12 months. The primary outcome measure was change in apical bone density by using the periapical index (PAI). Secondary outcome measures were proportion of teeth healed or improved in each group. Both groups exhibited equally favorable periapical healing at 12 months, with no statistically significant differences between groups.
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PMID:Outcome of one-visit and two-visit endodontic treatment of necrotic teeth with apical periodontitis: a randomized controlled trial with one-year evaluation. 1829 Dec 70

This study evaluated the incidence of postoperative pain after intracanal dressings with either 0.12% chlorhexidine digluconate gel (CHX) or a calcium hydroxide/camphorated paramonochlorophenol/glycerin paste (CH/CPMC). Overall, 138 asymptomatic teeth had their canals instrumented under irrigation with 2.5% NaOCl and then dressed with either CH/CPMC or CHX. The incidence of different intensity levels of postoperative pain was registered for the period between appointments. Data revealed that 84% of the total number of cases treated with either medicament showed absence of any level of pain. No case medicated with CH/CPMC and four cases (5.8%) medicated with CHX were categorized as flare-ups. There were no statistically significant differences between all possible comparisons involving the two medicaments in treatment/retreatment cases and teeth with/without apical periodontitis lesions. The low incidence of postoperative pain after the use of both medications, coupled to their antimicrobial effectiveness, gives support to using one or the other in routine treatment/retreatment.
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PMID:Postoperative pain following the use of two different intracanal medications. 1840 2

Calcium hydroxide is a widely used endodontic medicament for eliminating viable bacteria and inactivating virulence factors. Enterococcus faecalis, a pathogenic gram-positive bacterium, has been associated with refractory apical periodontitis. Because lipoteichoic acid (LTA) is a major virulence factor of gram-positive bacteria, we examined whether calcium hydroxide could detoxify LTA from E. faecalis. An enzyme-linked immunosorbent assay showed that calcium hydroxide-killed E. faecalis was less potent than heat-killed bacteria in stimulating the release of tumor necrosis factor-alpha by a murine macrophage line, RAW 264.7 (P < 0.05). Pretreatment of LTA with calcium hydroxide remarkably abrogated the ability of LTA to induce the release of tumor necrosis factor-alpha (P < 0.05). Furthermore, calcium hydroxide-treated LTA was not able to stimulate Toll-like receptor 2, which recognizes functionally intact LTA. These results suggest that calcium hydroxide could detoxify LTA, resulting in attenuation of the inflammatory responses to E. faecalis and its LTA.
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PMID:Calcium hydroxide inactivates lipoteichoic acid from Enterococcus faecalis. 1892 46

The aim of this study was to quantify radiographically the periapical bone resorption in dogs' teeth contaminated with bacterial endotoxin (LPS), associated or not with calcium hydroxide. After pulp tissue removal, 60 premolars were randomly assigned to 4 groups and were either filled with LPS (group 1), filled with LPS plus calcium hydroxide (group 2) or filled with saline (group 3) for a period of 30 days. In group 4, periapical lesion formation was induced with no canal treatment. Standardized radiographs were taken at the beginning of the treatment and after 30 days and the Image J Program was used for measurement of periapical lesion size. Periapical lesions were observed in groups 1 (average of 8.44 mm2) and 4 (average of 3.02 mm2). The lamina dura was intact and there were no areas of periapical bone resorption in groups 2 and 3. It may be concluded that calcium hydroxide was effective in inactivating LPS, as demonstrated by the absence of apical periodontitis in the roots that were filled with bacterial endotoxin plus calcium hydroxide.
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PMID:Quantitative radiographic evaluation of periapical bone resorption in dog's teeth contaminated with bacterial endotoxin (LPS) associated or not with calcium hydroxide. 1918 Mar 17

This prospective study investigated the frequency and intensity of postoperative pain and identified associated factors in adolescents undergoing two-visit root canal therapy. Sixty-four patients aged 11 to 18 years old presenting with molars with pulp necrosis were assigned consecutively to two visits (plus an interappointment dressing using calcium-hydroxide paste). Pain intensity was recorded on a visual analogue scale (VAS) of 0-5. Data were analysed using multivariate logistic regression. The frequency of postoperative pain was 32.8% (21/64), with intensities of VAS 1 and VAS 2 in 81%, VAS 3 in 14.3% and VAS 4 in 4.7% of the 21 cases in which it was experienced. Spontaneous preoperative pain (odds ratio (OR) = 6.60; 95% confidence interval (CI) = 1.61-26.97; P = 0.009) and absence of apical perodontitis (OR = 5.65; 95% CI = 1.34-23.87; P = 0.01) were associated with postoperative pain. The frequency of postoperative pain was high, but the intensity, in general, was low, including flare-ups. The presence of spontaneous preoperative pain and absence of apical periodontitis increase the probability of suffering from postoperative pain.
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PMID:Postoperative pain and associated factors in adolescent patients undergoing two-visit root canal therapy. 1970 82

Three clinical cases involving teeth with open apices and apical periodontitis were treated using different protocols. The first case was managed with intracanal calcium hydroxide paste for 12 months before obturation with gutta-percha and sealer. In the second case, an apical plug of mineral trioxide aggregate (MTA) was used before obturation with gutta-percha and sealer and treatment was completed during 2 appointments. In the third case, the tooth, which had a divergent root canal system, was completely obturated with MTA and treatment was also completed over 2 appointments. In all 3 cases, signs of bone healing were observed after treatment.
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PMID:Treatment options for teeth with open apices and apical periodontitis. 1984 May 2

Traditional methods of treatment of immature root with necrotic pulp and apical periodontitis pose multiple challenges. These challenges include disinfection of the root canal with standard protocols that aggressively use endodontic files, filling the root canal with an open apex that provides no barrier for stopping the root filling material before impinging on the periodontal tissues, and the susceptibility of the teeth to fracture because of their thin roots. Disinfection using sodium hypochlorite, apical barrier formation using calcium hydroxide as well as mineral trioxide aggregate, and pulp revascularization of fractured tooth with the help of blood clot and collagen-enhanced matrix has been discussed in detail in this article.
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PMID:Treatment of the immature tooth with a non-vital pulp and apical periodontitis. 2043 80

The aims of endodontic treatment in cases of apical periodontitis are to reduce as much as possible the number of microorganisms inside the root canal system and to inactivate toxins produced by them. Most of the times, these objectives are not achieved solely by chemomechanical preparation, and intracanal dressing may be necessary. In these cases, calcium hydroxide is used as a root canal dressing due to its well-known and recognized antimicrobial activity. Chlorhexidine has a wide spectrum of antimicrobial activity and its association with calcium hydroxide has been recommended in an attempt to amplify antimicrobial effects of calcium hydroxide. It is also known that dentin exerts a buffering effect under wide pH variations, and may be responsible for decreasing the antimicrobial activity of drugs inside the root canal. The objectives of this study were to assess the pH of 2% chlorhexidine gel and calcium hydroxide alone or in combination, as well as the influence of dentin on the pH of these compounds. Dentin powder was obtained from bovine teeth and added as 1.8% to the volume of the medications. All substances were individually stored in plastic flasks, in triplicate. A pH meter was used at five different moments to assess pH in viscous medium: immediately after preparation and after 24 h, and 7, 14, and 21 days. Results were analyzed by paired Student's t-test. Statistically significant differences were observed in the 2% chlorhexidine gel group alone or associated with calcium hydroxide and added of dentin powder (P < 0.05). Mean pH values indicated the influence of dentin powder because of a significant increase in pH. Calcium hydroxide with propylene glycol as the vehicle always showed high pH, demonstrating that this compound was not affected by the presence of dentin.
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PMID:Influence of dentin on pH of 2% chlorhexidine gel and calcium hydroxide alone or in combination. 2045 73


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