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Results for “Periapical Tissue”

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PubMed1989

[Bacteriological and immunological studies on the mechanism of development of periapical lesion. Immunobiological activities and localization in periapical lesion of the cellular components from Bacteroides buccae].

It has been strongly suggested that the periapical lesion develop as a result of immunopathological response to continuous antigenic stimulation. Bacteria from root canal systems might be most important pathogenesis capable of inducing immunological reactions in periapical tissue. The purpose of this study, therefore, was clarify the immunological potentials of Bacteroides buccae (B. buccae) which was frequently isolated from root canals with chronic periapical lesion. Biological activities of B. buccae cellular components, such as lipopolysaccharides (LPS) and cellular protein were investigated on the enhancement of monocytes migration induction of interleukin 1 (IL-1) production, mitogenicity and polyclonal B cell activation. The localization of immunocompetent cells and B. buccae in human chronic periapical lesions were examined by biotin-avidin-horseradish peroxidase method, and peroxidase antiperoxidase methods using monoclonal antibodies. Following results were obtained. 1. On the lymulus lysafe clotting activity and Shwarzman activity of B. buccae LPS were about half of Salmonella typhimurium (S. typhimurium). 2. Both LPS and 38K protein preparations from B. buccae enhanced the activity of human peripheral monocytes migration and induced IL-1 production. 3. It was found that mitogenicity of LPS from B. buccae on splenocytes of BALB/c and BALB/c nu/nu mice was weaker than that of 38K protein, however mitogenicity on thymocytes were not shown in both preparations. 4. The polyclonal B cell activation on splenocytes of BALB/c nu/nu mice by B. buccae were remarkably induced by 38K protein, but LPS showed less activity elicit than 38K protein. 5. It might be suggested that the both LPS and 38K protein of B. buccae may depend on the activities of macrophage and lymphocytes. 6. Antigenic substance of B. buccae were found most commonly engulfed materials within macrophage and intercellular space in connective tissue. 7. Dense accumulation of T and B lymphocytes were observed gathering around the phagocytic macrophage (foam cell), the number of B lymphocytes around the macrophage was greater than that of T lymphocytes. 8. These findings indicated that both LPS and 38K protein from B. buccae have a wide regulation function of immunobiologic responses. Therefore, it was suggested that both LPS and 38K protein from B. buccae may play significant roles in the pathogenesis of periapical lesion.

Bacteroides↗

PubMed1999

Eosinophil-derived transforming growth factors (TGF-alpha and TGF-beta 1) in human periradicular lesions.

Inflammatory mediators of periradicular lesions are poorly understood. Transforming growth factors-alpha and -beta 1 (TGF-alpha and TGF-beta 1) have been linked with the cellular processes for both soft and hard tissue wound healing. The purpose of this study is to demonstrate the cellular sources of TGF-alpha and TGF-beta 1 mRNA and protein in periapical lesions by in situ hybridization and immunohistochemistry. Nine periapical granulomas and nine periapical cysts were examined. TGF-alpha mRNA and protein were not detectable in the granulomas examined. However, eosinophils surrounding the periapical cysts demonstrated both TGF-alpha mRNA and protein. The vast majority of eosinophils present in the periapical granulomas and cysts also demonstrated TGF-beta 1 mRNA and protein. Other cells producing TGF-beta 1 were lymphocytes, fibroblasts, and monocytes. The presence of wound repair cytokines, such as TGF-alpha and TGF-beta 1, suggests a mechanism by which the host inflammatory response may participate in the repair and remodeling of periapical tissues.

Adult↗

PubMed1990

[Immunobiological activities of Veillonella parvula isolated from infected root canals].

The primary etiological agent of all periapical lesions has long been considered to be bacterial. Furthermore, bacteria from infected root canals are potential antigens capable of initiating immunological reactions in periapical tissues. The purpose of this study, therefore, was clarify the immunological potentials of Veillonella parvula (V. parvula), which was frequently isolated from root canals with periapical lesion. Immunobiological activities of V. parvula sonic extracts were investigated on the enhancement of monocytes migration, induction of interleukin-1 (IL-1) production, mitogenicity and polyclonal activation of B cell. Following results were obtained: 1. Both LPS and protein of V. parvula sonic extracts strongly enhanced the activity of human peripheral monocytes migration. 2. Induction of IL-1 on C3H/HeN mice macrophage by V. parvula sonic extracts were stronger than that of S. typhimurium LPS as positive control. 3. It was found that mitogenicity of LPS from V. parvula on splenocytes was stronger than that of the protein, however mitogenicity on thymocytes was not shown in both preparation. 4. The polyclonal activation of B cell on splenocytes of BALB/c nu/nu mice by V. parvula was induced by the protein and LPS. 5. These findings indicate that both the protein and LPS from V. parvula have a regulation of immunobiological responses against macrophages and lymphocytes.

Animals↗

PubMed1998

Histopathological study of the use of freeze-dried allogenic dentin powder and True Bone Ceramic as apical barrier materials.

The biocompatibility of freeze-dried allogenic dentin powder and True Bone Ceramics (TBC), the latter prepared by incineration of bovine bone, as apical barrier materials was evaluated histopathologically in dogs. After pulpectomy, 80 root canals of 53 dog premolar teeth were prepared, and each material was tightly packed to the apical stop area. The remainder of the canal was filled with guttapercha by the lateral condensation method. Control teeth were filled by the lateral condensation method using gutta-percha without constructing apical barriers. In both the teeth filled with the dentin powder and those filled with TBC, multinucleate giant cells appeared on the bone resorption surface and the surface of the root canal wall, and marked bone resorption and positive tartrate-resistant acid phosphate staining were observed. Hard tissue had formed on the root canal wall and the filling material after 3 months. These findings suggest that the test materials are nonirritative and compatible with periapical tissue, and that they may be useful and clinically applicable as apical barrier materials.

Animals↗

PubMed2005

Cytotoxicity analysis of alendronate on cultured endothelial cells and subcutaneous tissue. a pilot study.

The use of alendronate, a bisphosphonate which is able to inhibit bone resorption, in order to prevent dental root resorption after tooth replantation would be of clinical relevance. However, this drug must be biocompatible to the periapical tissues. The aim of this study was to analyze the effect of an alendronate paste in polyethyleneglycol (2 g ml(-1)) on endothelial cells in culture (in vitro) and on rat subcutaneous tissue (in vivo). For the in vitro study the paste was applied on round glass coverslips that were immersed into confluent cell cultures (clone Cips). The cell viability percentages of these cultures were obtained 0, 6 and 12 h after contact with the substance. As control, cultures that received plain coverslips were used. This analysis was carried out in triplicate using the Trypan blue dye exclusion assay. For the in vivo study the paste was introduced into polyethylene tubes that were placed into the rat subcutaneous tissue. The rats were killed 7 and 14 days later; then, the tissue sections stained with hematoxylin-eosin were analyzed. In vitro, the alendronate caused a significant decrease in the cell viability in 6 h (P < 0.05) and 12 h (P < 0.01), when compared with the control cultures. In vivo the tissue response was exuberant and similar at the two experimental times. There was a necrosis in a comprehensive area in contact with the open end of the tube. Presence of micro-abscesses and intense inflammatory infiltrate in the hypoderm permeating the muscle fibers and fat lobules were observed. In conclusion, the alendronate paste in polyethylene glycol as used showed to be highly cytotoxic in vitro as well as in vivo.

Alendronate↗

PubMed2004

Combined endodontic and surgical treatment of a three-rooted maxillary first premolar.

A case is reported in which endodontic treatment of a maxillary first premolar was complicated by the fact that the tooth had three roots. One of the roots was completely calcified and therefore could not be negotiated with endodontic files. There was a large periapical lesion associated with the tooth and this was surgically removed. During the surgical procedure a retrograde cavity was prepared on the calcified root using ultrasonic instruments and this was filled using Super EBA cement. Twelve months later the tooth was asymptomatic and the periapical tissues had completely healed.

Aged↗

PubMed1991

[Anaerobes in infected canals: a preliminary study].

Anaerobes of 17 infected canals with periapical periodontitis were studied. Most of root flora were not only anaerobes but also aerobes. Anaerobes were predominant in chronic periapical periodontitis. Major anaerobes isolated from canals were peptostreptococcus, B. melaninogenicus and B. oralis. The chi-square results indicated that the peptostreptococcus were significantly related to apical radiolucency and B. melaninogenicus were significantly related to percussion or foul smell. Animal experiment results showed that rats inoculated with mixed flora developed many abscesses. But the monoinfected rats had infiltration of PMNs, dilation and hypermia of vessels. B. melaninogenicus, B. oralis and mixed flora had liquefied gelatin and indicated these bacteria had collagenase which could dissolve collagen fibers and significantly related to destroy of collagen fibers and bone in periapical tissues.

Adolescent↗

PubMed2002

The effect of a bioresorbable matrix barrier in endodontic surgery on the rate of periapical healing: an in vivo study.

The purpose of this prospective clinical study was to assess the rate of healing of periapical bony defects created at the time of endodontic periapical surgery by measuring the densitometric ratio change in periapical osseous tissues, after periapical endodontic surgery was performed, by using or not using Guidor bioresorbable membrane material. Periapical surgeries were performed on 25 patients where nonsurgical root canal therapy had failed and a periapical lesion was present. For inclusion in the study, the osseous defect to be analyzed had to be confined to the apical area, with bone covering the entire root surface coronally, and an intact lingual cortical plate had to be present. A series of radiographs at the 3-, 6-, and 12-month recalls were compared with the radiograph taken immediately after surgery by using digital imaging and a densitometric ratio that gave a numerical estimation of osseous healing. Using repeated-measure ANOVA, it was shown that there was no statistical difference between the rate of healing in those cases where a Guidor resorbable membrane was used and those cases where no membrane was used. The results suggest that placement of a guided tissue membrane over the bony opening created during an endodontic periapical surgical procedure has no beneficial effect on the rate of healing and the added expense to the patient would not be warranted in these cases.

Absorbable Implants↗

PubMed1989

The relative frequency of periapical lesions in teeth with root canal-retained posts.

This study was concerned with the relation between technical quality of root filling seal in teeth with posts and radiographic status of the periapical tissues. Full-mouth series from 298 randomly chosen patients were examined by two observers. Endodontic treatment had been performed in 852 roots and posts were observed in 424 of these. Periapical radiolucencies were judged to be present in 16% of roots with posts and in 13% of roots without posts. Roots with posts in which the remaining root filling was shorter than 3 mm showed a statistically significant higher frequency of periapical radiolucencies (p less than 0.01). It was found that an improper seal was more unfavorable in roots with posts (p less than 0.05). The findings in this study indicate that the placement of a post will not per se decrease the probability of periapical healing. It also suggests that the remaining root filling must not be shorter than 3 mm.

Chi-Square Distribution↗

PubMed2003

Minimally invasive periapical curettage of foreign materials in periapical lesions using a fiberscope.

The design and development of a new fine fiberscope (1.0 mm outer diameter) is described, that includes an irrigation system for endoscopic use. This effectively allows visualisation of fields involved in periodontal disease. This fiberscope has been used in our clinic for seven years to diagnose and treat periapical and periodontal lesions through fistulae and periodontal pockets. The fiberscope has been applied to endodontic surgery for the inspection of root apices and the denuded root surfaces, in addition to the cut root face, rootend cavity and root-end filling after root-end resection. The advantages of endoscopy compared to surgical microscopy are portability and easy adjustment of direct viewing angle to examine around corners without the use of additional mirrors. Furthermore, the fiberscope can be utilised through the sinus tract or a minimal incision without the need for surgical flaps to observe the root surface, periapical tissue and foreign materials before, during and after curettage. The system requires little local anaesthesia, no large incisions, no opening flaps and no sutures. As a result, postoperative symptoms are minimised. Periapical curettage using a fiberscope represents a useful and minimally invasive surgical procedure.

Dental Fistula↗

PubMed1983

An unusual instance of leukemic infiltrate. Diagnosis and management of periapical tooth involvement.

The clinical course of an adult patient with relapsed acute myelogenous leukemia and leukemic infiltrate periapical to the dentition is described. While the oral symptoms were indicative of pulpal disease requiring dental therapy to resolve the patient's complaint, roentgenographic, dental pulp testing, and histologic analysis revealed extramedullary infiltrate apical to a mandibular molar. The findings developed coincident with relapse of leukemia; the medical and dental testing described above were essential in establishing an accurate diagnosis. While most oral leukemic infiltrates affect the gingiva, in this patient the infiltrate involved periapical tissue which was not clinically observable.

Adult↗

PubMed1990

[Pathogenesis of periapical inflammatory processes].

The Authors, after a short description of the anatomy of the root canal, deal with the aetiological factors of the periapical pathology, acute and chronic. They examine the pathogenetic mechanisms of acute flogistic process of the periapical tissue and consider the principal mediators involved in the tissue lesion.

Dental Pulp Cavity↗

PubMedDate not supplied

[Etiopathogenesis of periapical lesions].

In recent years, considerable interest has been generated in the role of bacteria in causing periapical pathogenesis. This article reviews and correlates clinical and laboratory research bearing on this important topic. Bacteria in dental root canals play a decisive role in the development of periapical lesions and some of them have the ability to establish themselves in periapical tissue. Multiple mechanisms are involved: they include also immunological responses.

Actinomyces↗

PubMed1998

Microorganisms in closed periapical lesions.

The purpose of this study was to investigate the microorganisms of strictly selected closed periapical lesions associated with both refractory endodontic therapy and pulpal calcification. Definitive criteria were established that assured complete clinical isolation of the periapical lesion from the oral and periodontal environment. A total of 13 criteria-referenced lesions were selected from 70 patients with endodontic surgical indications. A well controlled culturing method was used in all cases and samples were taken by one clinician at three separate sites during each surgery. Samples taken at the surgical window and within the body of the lesion served as controls, whilst a third sample was taken at the apex. In all 13 cases, samples taken from the apex yielded microorganisms comprising 63.6% obligate anaerobes and 36.4% facultative anaerobes. Prevalence of the isolated species was 31.8% for Actinomyces sp., 22.7% Propionibacterium sp., 18.2% Streptococcus sp., 13.6% Staphlyococcus sp., 4.6% Porphyromonas gingivalis, 4.6% Peptostreptococcus micros and 4.6% Gram-negative enterics. The results of this investigation indicate that closed periapical lesions associated with calcified teeth or those resistant to root canal treatment harbour bacteria. The inability to eradicate all root canal microorganisms during root canal treatment, along with anatomical factors, may allow further bacterial colonization of the root apex and surrounding periapical tissues, and consequently prevent healing.

Bacteria, Anaerobic↗

PubMed1982

Periapical actinomycosis. Report of a case and review of the literature.

An analysis of actinomycosis in periapical inflammatory lesions in the English-language literature was carried out. Nineteen cases were found, and an additional case is presented. The most frequent locations for these infections were the maxillary central incisor region and the mandibular first molar region. The average age of the patients was 27.5 years, and a slight male predilection was noted. Formation of draining sinuses, local swelling, and pain were the most common presenting symptoms. Many of the cases were diagnosed following endodontic procedures, suggesting that such procedures might be responsible for introducing the organisms into the periapical tissues or that the organisms might be responsible for some cases of endodontic failure.

Actinomycosis↗

PubMed1985

Paste technique re-treatment study: a clinical, histopathologic, and radiographic evaluation of 50 cases.

This study correlated clinical, radiographic, and histopathologic aspects of 50 endodontic failures involving the paste technique. All clinical and radiographic findings were recorded. The teeth were re-treated with gutta-percha/Kloroperka and lateral condensation. Subsequently, periapical surgery, including retrograde amalgam filling, was performed for the removal of material in the periapical tissue. The resulting biopsy specimens were processed for histologic evaluation. Although neutrophilic leukocytes predominated in some cases, all types of inflammatory cells were present. Macrophages and foreign body cells contained paste particles. The blood pigment distinguished hemorrhage due to surgery from pathologic circulatory changes. There was resorption/apposition of bone and root fragments. Epithelial strands and parts of cyst walls were observed. There was a correlation between a periapical radiolucency and inflammation but no correlation between amounts and types of inflammatory cells and pain. Paste placed beyond the foramen caused tissue damage and reduced prognosis.

Balsams↗

PubMed1992

The role of intracanal medication in root canal treatment.

The role of intracanal medication as a root canal dressing is re-examined. In pulpectomy and some root canal treatments, where the root canal contains vital pulp tissue, it is doubtful whether a routine intracanal medicament is needed. In infected root canals, intracanal medication has been advocated for many purposes. An intracanal medicament is used to: (i) eliminate any remaining bacteria after canal instrumentation; (ii) reduce inflammation of periapical tissues and pulp remnants; (iii) render canal contents inert and neutralize tissue debris; (iv) act as a barrier against leakage from the temporary filling; (v) help to dry persistently wet canals. However, most of the indications for intracanal medicaments are questionable. Intracanal medicaments should only be used for root canal disinfection as part of controlled asepsis in infected root canals, and their role is secondary to cleaning and shaping of the root canal. Thorough canal debridement and adequate canal preparation are more pertinent, and their importance is emphasized. Bacteriological sampling may be necessary if a tooth does not respond to treatment, to help in the choice of intracanal medicament.

Adrenal Cortex Hormones↗

PubMed2003

Effect of black-pigmented bacteria on the plasminogen-plasmin system in human pulp and osteoblastic cells.

OBJECTIVE: To date, there have been relatively few studies addressing the presence and expression of the plasminogen-plasmin system at the site of bacterial infection. The aim of the present study was to investigate the effect of black-pigmented bacteria on the expression of the plasminogen-plasmin system in human pulp and osteoblastic cells. STUDY DESIGN: The supernatants of Porphyromonas endodontalis, Porphyromonas gingivalis, and Prevotella intermedia were used to evaluate tissue-type plasminogen activator (t-PA) and type 1 plasminogen activator inhibitor (PAI-1) gene expression in human pulp and osteoblastic cells. The levels of mRNA were quantitatively measured by using reverse transcription-polymerase chain reaction. RESULTS: In this study, black-pigmented bacteria induced not only t-PA but also PAI-1 gene expression in human pulp and osteoblastic cells. In addition, the ratio of t-PA to PAI-1 was higher in human pulp and osteoblastic cells stimulated by black-pigmented bacteria than in untreated cell cultures (P <.05). CONCLUSIONS: A fine balance exists in the expression of components of the plasminogen-plasmin system, whereby tissue homeostasis is maintained. Black-pigmented bacteria activate the activator-inhibitor system in human pulp and osteoblastic cells through unbalance regulation of t-PA and PAI-1, which might result in an uncontrolled degradation of pulpal and periapical tissues.

Analysis of Variance↗