Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Periapical Tissue”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 271 records · Page 15Linked to original sources
PubMed2000

Utilization of gutta-percha for retrograde root fillings.

Just as gutta-percha used with a root canal sealer is a recommended material for orthograde root fillings, it could similarly be the material of choice for retrograde fillings. Unfortunately, clinical accessibility and visibility do not always facilitate such a technique. The aim of this article is to present a new technique which enables retrograde fillings to be achieved with gutta-percha and a sealer. After the apex had been resected, a hole was drilled perpendicular to the plane of section of the apex about 1 mm coronally. The bucco-lingual depth required to reach the main canal was calculated. The cavity was then dried, coated with the sealer, and obturated with gutta-percha in accordance with thermo-mechanical compaction techniques. After excess filling material had been removed, the gutta-percha was cold burnished and the angles of the root were smoothed. Clinical cases illustrating healing of the periapical tissues are shown.

Apicoectomy↗
PubMed1980

Tissue reactions following apical plugging of the root canal with infected dentin chips. A histologic study in dogs' teeth.

The object of the present work was to observe whether the condensation of a plug of infected dentin in the apical region, before the filling of a root canal, could show results similar to those found in the absence of contamination. The histologic analysis of the periapical tissues of dogs' teeth containing infected apical plugs showed results that were totally unfavorable, when compared to cases in which the plugs were absent. Such data do not encourage the use of dentin plugs for cases of contaminated root canals, at least until other experiments can better clarify the problem.

Animals↗
PubMed1988

Endodontic retreatment decision making among a group of general practitioners.

Large interindividual variations have been demonstrated when dentists suggest clinical management of endodontically treated teeth. Since variations also have been shown in radiographic diagnosis of the periapical tissues, a hypothesis was tested that explains variation in treatment as a function of variation in diagnosis. Fifty-four general practitioners suggested diagnosis and management of 32 endodontically treated roots. Spearman's rank correlation coefficient reached 0.298 when the examiners were definitely sure of the presence of a periapical lesion, and 0.356 when probable lesions also were included. Conclusively, the hypothesis seemed to have a limited value in explaining why dentists carry out retreatment. Instead a multi-aspect approach to this problem is suggested.

Attitude of Health Personnel↗
PubMed1988

Silver accumulations in periapical granulomas: report of five cases using the scanning electron microscope, the electron microprobe, and other complementary methods.

A series of cytologic imprints obtained from periapical granulomas were studied with the conventional light microscope, the scanning electron microscope, and the electron microprobe to analyze the chemical composition of several black deposits that were randomly observed near or in the cytoplasm of macrophages and multinucleated giant cells. These granulomas had been removed from endodontically treated human teeth in which the root canals had been obturated with silver cones and Grossman's sealer 3 to 5 years previously. To investigate whether corrosion had occurred on the silver cones, the cones were also examined with the scanning electron microscope and the electron microprobe. Our observations revealed that all the examined silver cones showed different degrees of corrosion on their surfaces, whereas different concentrations of silver, sulfur, and chlorine were detected at the same sites in the cytologic imprints. However, it is impossible to determine from this study whether the presence of corrosive by-products in the periapical tissues is responsible for the development of a pathologic reaction at these sites.

Adolescent↗
PubMed1994

Pathogenesis of induced rat periapical lesions.

Studies of the mechanisms of pathogenesis of periapical lesions were undertaken using a rat model of surgical pulp exposure. In this model, periapical lesions develop rapidly between days 0 and 15 (active phase) and more slowly thereafter (chronic phase). A Gram-negative anaerobic flora, similar to that seen in human beings, are quickly established. Lesions contain a mixed inflammatory cell infiltrate consisting of T cells, neutrophils, B cells, macrophages, and plasma cells. Helper T cells predominate during the active phase, whereas suppressor T cells are more frequent in the chronic phase. Extracts of periapical lesions contain bone-resorbing activity, the highest levels of which are present when lesions are actively expanding. Most bone-resorbing activity is mediated by the cytokine interleukin-1 alpha, as determined by biochemical criteria and antibody neutralization studies. Prostaglandin2 accounts for 10% to 15% of resorptive activity. Cells that express interleukin-1 alpha were identified in pulp beginning on day 2 after exposure and in periapical tissue beginning on day 7, as determined by in situ hybridization and immunostaining. Macrophages, fibroblasts, neutrophils, and osteoclasts were positive for interleukin-1 alpha mRNA and protein. Cells that express tumor necrosis factor alpha were also detected, whereas cells expressing interleukin-1 beta or tumor necrosis factor beta were absent. Finally, periapical bone destruction was inhibited by 60% by treatment with interleukin-1 receptor antagonist. These studies establish a key role for interleukin-1 alpha in the pathogenesis of periapical lesions in the rat model.

Alveolar Bone Loss↗
PubMed1991

Histological study of therapy for infected nonvital permanent teeth with incompletely formed apices.

The histological response of periapical tissues to root canal fillings with calcium hydroxide (Ca(OH)2)-iodoform paste, Vitapex (Neo Dental Chemical Products Co., Ltd., Tokyo, Japan), and Ca(OH)2-camphorated paramonochlorophenol (CMCP) paste in nonvital permanent teeth with incompletely formed apices was investigated in 160 root canals from 90 dog premolar and incisor teeth. Periapical inflammatory lesions were initially induced in the experimental teeth. After debridement and cleaning, root canals were filled with one of the two materials. The animals were sacrificed after 30, 60, 120, or 180 days, and histological sections of each specimen were prepared with hematoxylin and eosin staining. Histological findings showed periapical repair and apical closure in both experimental groups. However, the differences in the level of inflammation, apical closure, and reparative process among the two groups were significant (p less than 0.05). It was concluded that the Ca(OH)2-iodoform paste, Vitapex, produced better results than Ca(OH)2-CMCP paste in treatment of infected nonvital permanent teeth with incompletely formed apices.

Animals↗
PubMed2006

Electronic root canal length measurement before and after experimentally induced pulpitis and apical periodontitis in dogs.

The aim of the study was to examine the influence of the state of the pulp and apical periodontium on the results of electronic root canal length measurement (ERCLM) with a resistance measuring device in dogs. Pulpitis and apical periodontitis were induced by pulp exposure and contamination by the oral flora in the premolar teeth of six mongrel dogs, comprising four experimental groups (36 root canals). In a control group, measured lengths of teeth with uninfected pulps were performed on the first experimental day (44 root canals). In all animals the ERCLMs were performed on teeth with healthy pulps, and at the end of the experimental period (20, 35, 50 and 65 days) following pulp exposure. The point of measuring canal lengths was the anatomical obstacle above the apical delta. Electronically measured lengths (EML) were compared between each other and with the root canal length established by tactile-sense measurement verified radiographically. The EMLs were less accurate in teeth with healthy pulps and teeth with pulpitis in the third experimental group (dif=2.27 x 2.65 mm(2); t test, p<0.05), while they were most precise after 65 days in teeth with completely necrotic pulp and established chronic apical periodontitis (dif=0.54 x 1.36 mm(2); t test, p>0.05). These results suggest that the state of the pulp and periapical tissue may have an influence on the ERCLM.

Animals↗
PubMed2002

Effect of calcium hydroxide on bacterial endotoxin in vivo.

The aim of this study was the histopathological evaluation of apical and periapical tissues in dog teeth that were submitted to bacterial endotoxin, associated or not with calcium hydroxide. After removal of the pulp from 60 premolars, the teeth were divided into four groups and were filled with bacterial endotoxin (group 1), bacterial endotoxin plus calcium hydroxide (group 2), saline solution (group 3), or had induced periapical lesions with no treatment (group 4). After 30 days, animals were killed and the teeth processed histologically. The inflammatory infiltrate, the thickness of the periodontal ligament, and the presence of resorption areas were similar for groups 1 and 4. Groups 2 and 3 were similar to each other. It can be concluded that the bacterial endotoxin caused a periapical lesion and that calcium hydroxide detoxified the lipopolysaccharides in vivo.

Animals↗
PubMed2005

[Endodontic treatment and periapical health in patients of the Institute of Dentistry in Lódź].

OBJECTIVE: Retrospective assessment of periapical health in relation to sex, age and quality of root-canal treatment among adult patients of the Institute of Dentistry in Lódź. Orthopantomograms of 439 subjects were assessed considering the prevalence of endodontic treatment, technical quality of root-canal fillings and the state of periapical tissues. The assessment of orthopantomograms of 174 (39.6%) men and 265 (60.4%) women was carried out. A significant increase (p=0.016) in the mean number of endodontically treated teeth according to age (range from 1.4 in subjects under the age of 20 to 3.4 in those aged 70 years and over) and the mean number of teeth with periapical pathosis (from 0.9 to 2.4, respectively) (p=0.020) was observed. Of 10054 radiographically examined teeth 9.7% was treated endodontically, whereas, 5.5% exhibited periapical pathosis. The percentage of teeth with periapical lesions was significantly higher (p=0.015) in men (6.2%) as compared to women (5.0%). Periapical radiolucency occurred significantly more often (p=0.0001) in endodontically treated teeth (36.4% of cases) than in those with untreated root canals (2.1%). Teeth with inadequately filled root canals significantly more often revealed the presence of periapical pathosis (49.6%) in comparison to teeth with adequately filled root canals (4.2%). CONCLUSIONS: The prevalence of endodontic treatment and apical periodontitis increases with age. The prevalence of apical periodontitis depends on sex - periapical lesions were more often found in men. The quality of endodontic treatment significantly affects periapical health.

Adult↗
PubMed2003

[Magnetic laser therapy in the treatment of apical periodontitis].

A new method for the treatment of apical periodontitis, making use of Optodan laser, differs from the known method by more rapid periapical tissue regeneration, which is paralleled by high antiinflammatory effect of magnetic laser therapy at early stages of treatment.

Adolescent↗
PubMed2003

Cytomegalovirus and Epstein-Barr virus active infection in periapical lesions of teeth with intact crowns.

Herpesviruses seem to play an important role in the pathogenesis of aggressive periodontitis and may also contribute to periapical pathosis. This study determined the presence of human cytomegalovirus, Epstein-Barr virus, and herpes simplex virus productive infection in five symptomatic periapical lesions of teeth having intact crowns and calcified necrotic pulps. Periapical samples were collected in conjunction with periapical surgery and kept frozen until virological examination. Reverse transcription-polymerase chain reaction was used in herpesviral identification. RNA was isolated from periapical tissue by a guanidinium isothiocyanate-acid phenol procedure. cDNAs were generated from highly conserved regions of the test viruses using a preamplification kit. Sensitivity and validity of the PCR-primers were determined according to established methods. Amplification products were identified using gel electrophoresis. Human cytomegalovirus and Epstein-Barr virus dual transcription was detected in all five periapical lesions studied. Herpes simplex virus transcript was not identified in any lesion. The present data suggest that human cytomegalovirus or Epstein-Barr virus activation participate in the pathogenesis of symptomatic periapical lesions. We hypothesize that periapical active herpesvirus infection impairs local defenses, thereby inducing overgrowth of endodontopathic bacteria and the clinical flare-up of inflammation.

Cytomegalovirus↗
PubMed1988

[Analysis of odontogenic perimaxillary inflammation processes].

Basing on retrospective analysis of 542 case histories the causes producing purulent perimaxillary inflammation processes most frequently have been presented taking causal teeth, their treatment method and the state of periapical tissues into consideration. From the analysis of the material it follows that never-treated teeth with gangrenous pulp (46.3%) are the most frequent cause of perimaxillary abscess while the teeth treated endodontically were the cause of these pathologic states in 24.3% of the cases. The specific observations prove the results obtained by other authors, namely that the teeth treated endodontically without periapical inflammatory changes are rarely the cause of perimaxillary purulent processes.

Dental Pulp Necrosis↗
PubMed1998

[The clinical evaluation of the quality of tooth filling after exposure to hydroxyethylidene diphosphonic acid].

Ultrastructure of dental enamel was examined under electron microscope after exposure to hydroxyethylene diphosphonic (HEDP) acid and prophilometry of enamel surface was carried out after its exposure to acid salts; clinical studies in 105 patients aged 18-50 years with different diseases of hard dental tissues were carried out in order to assess the duration of filling preservation after dental enamel treatment with HEDP salts. Clinical results were assessed from subjective sensations of patients and data of examination. The criteria of assessing the results were presence of a filling in a filled carious cavity, marginal adhesion of the filling, alteration of color along the external interface of the filling, caries relapses, status of dental pulp and periapical tissues. Clinical and laboratory studies showed that treatment with HEDP acid creates favorable conditions for tooth filling.

Acid Etching, Dental↗
PubMed1989

The endo-antral syndrome: an endodontic complication.

Infection of pulpally involved teeth near the maxillary sinus sometimes spreads into the sinus and causes serious complications. This pathological complex, involving both antral and periapical tissues, is referred to as the endo-antral syndrome (EAS). It includes diagnostic difficulties, treatment considerations, and occasionally persistent pathological antral alterations after nonsurgical endodontic therapy. Surgical measures are occasionally required to stimulate healing and preserve the teeth.

Adult↗
PubMed2006

Evaluation of periapical repair following retrograde filling with different root-end filling materials in dog teeth with periapical lesions.

OBJECTIVE: The objective of this study was to evaluate periapical repair following retrograde filling using different root-end filling materials. STUDY DESIGN: After induction of periapical lesions, 48 root canals from dog teeth were partially filled. Endodontic surgery was performed and 3 different materials were used for root-end filling: Sealer 26, Sealapex plus zinc oxide, or mineral trioxide aggregate (MTA). No additional procedures were performed in the control group after partial filling of the root canal. After 180 days, the animals were killed, the maxillas and mandibles were removed, and specimens were submitted for histologic processing. RESULTS: Histopathologic analysis revealed similar periapical repair for the groups in which Sealer 26, Sealapex plus zinc oxide, and MTA were used (P > .05). The control group showed unsatisfactory periapical repair (P < .05). CONCLUSION: There was no difference in periapical tissue healing after retrograde filling with the tested materials, which indicates that these 3 root-end filling materials are equally useful.

Aluminum Compounds↗
PubMed1987

Innervation of rat molar teeth: II. A quantitative analysis of primary sensory neurons innervating a mandibular molar tooth.

This study was conducted to determine the source and number of primary sensory neurons (PSNs) innervating a mandibular molar tooth of a population of 15-18-week-old Sprague-Dawley rats. The pulpal tissue was exposed to horseradish peroxidase (HRP) pellets for 24 hours. Subsequently the animals were perfusion fixed and the following PSN structures were examined for the presence of HRP-labelled cells: trigeminal (TGs) and cervical dorsal root ganglia (DRGs) and mesencephalic nucleus (MN). Only the TGs contained labelled cells and they thus were the sole source of PSN pulpal innervation. The number of TG cells was highly variable, 49-407, but most of this variability was attributable to insufficient HRP filling of the pulp chamber or leakage of HRP into periapical tissue. Selection of TGs whose respective experimental teeth demonstrated that HRP filled and was restricted to the pulp chamber revealed a narrower range of TG cells providing pulpal innervation to the first molars, 142-288, with an average of 213. A detailed mapping of these cells indicated a somatotopic distribution within the mandibular territory of the TGs. It was concluded that these findings represent TG's contribution to the pulpal innervation of this specific population of rat first molar teeth. This suggests that from animal to animal the density of innervation may be quite variable and it is hypothesized that the sensitivity of the pulp would likewise vary. In addition, these findings may contribute to the explanation of why there is variability in the stimulus strength needed to elicit a pain response in the human dentition.

Animals↗
PubMed1998

Coronal leakage: endotoxin penetration from mixed bacterial communities through obturated, post-prepared root canals.

Coronal leakage has been considered as one of the major causes of failure in root canal treatment. Bacteria have been shown to penetrate the root canal obturating materials and influence the periapical tissues. Endotoxin, a component of Gram-negative bacteria, is a potent inflammatory agent and may be able to penetrate obturating materials faster than bacteria. This in vitro study examined the possible penetration of post-prepared canals by endotoxin and bacterial cells derived from mixed bacterial communities. Results showed that both bacteria and endotoxin were able to penetrate the obturating materials in post-prepared canals; however, endotoxin penetration was faster than bacterial. If one speculates that a similar sequence of events occurs clinically, then such a rapid penetration of endotoxin could lead to an early periapical reaction, with subsequent treatment failure and need for retreatment or periapical surgery. The need for an immediate and proper coronal restoration after root canal treatment is therefore reinforced.

Analysis of Variance↗
PubMed2001

[IL-1alpha, IL-1beta and TNF-alpha mRNA expression in experimental periapical lesions in the rat].

OBJECTIVE: IL-1alpha, IL-1beta and TNF-alpha mRNA expression were analyzed in rat experimental periapical lesions to understand the relationship between the aforementioned cytokines and periapical lesion. METHODS: The molar tooth pulps of 16 SD rats were surgically exposed and left open to permit infection from the oral environment. Total cell RNA was isolated from periapical tissue obtained on days 3, 7, 14 and 28 after exposure. mRNA for IL-1alpha, IL-1beta and TNF-alpha was amplified by reverse transcription polymerase chain reaction(RT-PCR), and levels were estimated by comparison to the parallel amplification of the housekeeping gene beta-actin. RESULTS: IL-1alpha,IL-1beta and TNF-alpha mRNA were all expressed beginning on day 7, peaked on day 14, and declined somewhat on day 28, but IL-1beta mRNA was expressed at much lower levels with the same kinetics (P<0.01). CONCLUSION: IL-1alphaand TNF-alpha may be primarily cytokines in rat periapical lesion model.

English Abstract↗