Biomedical subjects

M Tagger

Publications and source records attributed to M Tagger.

At least 19 recordsLinked to original sources

PubMed2004

A standard for radiopacity of root-end (retrograde) filling materials is urgently needed.

AIM: To assess the radiopacity of materials used, or recommended for use, as apical root-end (retrograde) fillings. METHODOLOGY: The radiopacity of 14 materials falling into the category of root-end filling materials was measured in equivalent millimetres of aluminium (mm Al) using a new computerized method. These included temporary or intermediate sealing materials; composite, compomer and GIC filling materials; EBA-derived cements; amalgam, etc. Gutta-percha cone material was added as a control. Samples of 1 mm thickness were radiographed on periapical film alongside an aluminium step wedge calibrated in millimetres, and the opacity of the materials, in greyscale or pseudo-colour, was compared with the equivalent step. RESULTS: The radiopacity ranged from 1.75 mm Al to >10 mm Al. The lower range appears insufficient for routine clinical detection when it is compared with the minimal requirement for intracanal fillings. CONCLUSIONS: Because of the proliferation of root-end filling materials with a broad range of radiopacity, an international standard stipulating the required minimal radiopacity, as well as other properties, is needed urgently. It should be based on in vitro results and on large-scale clinical radiographic surveys.

Contrast Media↗

PubMed2000

Russell bodies in the pulp of a primary tooth.

Russell bodies can be found in the majority of the inflamed tissues throughout the body. They have been shown to consist of accumulations of normal globulins that may burst out of the distended plasma cells that secrete them. Russell bodies have also been described in oral tissues and are believed to occur in 80% of the chronic periapical lesions. Yet their occurrence in the pulp has not been subjected to scrutiny. Concentrations of large intracellular (in-plasma cells) and extracellular Russell bodies have been found in the inflammatory tissue occupying the pulp cavity of carious primary teeth. Their significance is so far unknown.

Child, Preschool↗

PubMed2000

The effect of immediate vs. delayed post space preparation on the apical seal of a root canal filling: a study in an increased-sensitivity pressure-driven system.

A 5 mm remaining length of root canal filling, after post space preparation, is commonly assumed to maintain sealing ability similar to that of the intact filling. Post spaces were prepared either immediately using hot pluggers, or later, using drills. The sealing ability of the fillings, 5 mm remaining length, were compared with each other and with an intact root canal filling control, using radioactive tracer in a pressure-driven system. When no pressure was applied, no differences could be detected between either of the groups and the control. When a pressure of 120 mm Hg was applied to the same teeth, the control group clearly maintained a better seal than each of the experimental groups, which did not significantly differ from each other. These results suggest that (a) the pressure-driven system was more sensitive than the passive leakage assay that failed to detect differences even at 14 days; (b) a remaining root canal filling of 5 mm was inferior to the intact root canal filling; and (c) the immediate post space preparation with hot pluggers did not differ from a delayed preparation with drills.

Analysis of Variance↗

PubMed2000

Correlation between remaining length of root canal fillings after immediate post space preparation and coronal leakage.

The seal provided by root canal fillings after post space preparation was studied using a pressure-driven radioactive tracer assay. The coronal part of root canal fillings was immediately removed, using a hot plugger, to a remaining length of either 3, 5, 7, or 9 mm. Intact root canal fillings of 14 mm served as control. Application of air pressure of 130 mm Hg to the tracer solution drove it through the fillings and into phosphate-buffered saline surrounding the apex. Leakage gradually increased for 28 days, and differences in the leakage through 3 to 9 mm fillings were demonstrated. In a passive system by which an additional group of teeth were tested none of these differences could be detected. It was concluded that: (a) root canal fillings of 3, 5, and 7 mm have an inferior seal, compared with that of an intact filling; (b) the sealing is proportional to the length of the remaining filling; and (c) a passive system is unable to detect these differences, even when conducted for as long as 28 days.

Analysis of Variance↗

PubMed1996

Sealing ability of a new hydroxyapatite-containing endodontic sealer using lateral condensation and thermatic compaction of gutta-percha, in vitro.

A new sealer that contains hydroxyapatite has been developed; the additive is assumed to influence apical healing, but it may also affect the sealing ability of the cement because of its composite structure. The purpose of this study was to evaluate the sealing ability of Bioseal and to compare it with that of another zinc oxide-eugenol sealer (Pulp Canal Sealer), using a lateral condensation technique and thermatic compaction of gutta-percha. The study was conducted on 42 straight roots, prepared to apical size 35 to 40 and randomly separated into four groups. After obturation, the roots were suspended for 1 wk in methylene blue and sectioned transversely for measuring penetration of the dye. In the roots filled with Bioseal, the mean penetration was 1.1 mm for lateral condensation and 1.5 mm for thermatic compaction. In the Pulp Canal Sealer groups, the values were 1.4 mm for both. The difference was not significant at the 5% level (Mann-Whitney U test), indicating that the additive did not adversely affect the sealing properties.

Dental Leakage↗

PubMed1996

Intracanal pH changes of calcium hydroxide pastes exposed to carbon dioxide in vitro.

It has been suggested that the main benefit of using calcium hydroxide as an intracanal medicament lies in its bactericidal effect, provided that the pH of the paste is above 12.5. The purpose of this study was to measure changes in the pH of several calcium hydroxide pastes sealed in root canals for 30 days. Sixty-two extracted, single-rooted human teeth were endodontically prepared using K-files up to size 60. The teeth were separated at random into six equal groups to be filled with either Calxyl, Hydrocalcium, or a paste made by mixing calcium hydroxide powder with either distilled water, camphorated p-monochlorophenol, local anesthetic solution, or Solvidont. Cavidentin was used to seal the coronal orifice of the teeth that were placed individually in vials containing 10 mL distilled water. Five vials of each group were exposed to air at room temperature, whereas the other five vials were exposed to carbon dioxide in a closed container. The pH of the paste in the root canal was measured after 30 days. There was no significant (p > 0.01) change in the pH (mean 13.11) of the pastes placed in teeth before and after exposure to air, whereas the pH of the pastes in teeth exposed to carbon dioxide was significantly (p < 0.01) reduced (mean 12.54). There was no significant difference in pH between the six preparations. After 30 days of exposure to carbon dioxide, they still maintained a purportedly bactericidal pH within the root canal.

Analysis of Variance↗

PubMed1994

Apical seal using the GPII method in straight canals compared with lateral condensation, with or without sealer.

The purpose of this study was to test the apical seal provided by a recently introduced low-fusing gutta-percha, GPII, compared with lateral condensation, with or without a sealer. For this study, 84 roots with straight circular canals separated from extracted teeth were prepared to K-file size 45. A standardized gutta-percha master cone was fitted to 80 of these roots. The roots were then randomly separated into four groups of 20 each and filled with GPII or laterally condensed gutta-percha, with or without AH26 sealer. The roots were immersed in India ink, subjected to vaccuum for 2 hours and kept in the marker for 4 days for the study of apical leakage. Four unfilled roots served as an experimental control. The teeth were demineralized, cleared in methyl salicylate and examined with a stereomicroscope. When no sealer was used, 12 roots filled with GPII leaked from 0 to 2.5 mm and in the lateral condensation group ink penetrated from 0 to 6 mm in 14 roots (difference not significant at the 0.05 level). None of the specimens in which sealer was used showed any penetration of ink beyond the end of the preparation of the canal regardless of the filling technique.

Bismuth↗

PubMed1994

Periodontal ligament injection: spread of the solution in the dog.

Investigations of the spread of anesthetic solutions administered with the periodontal ligament injection have reported conflicting findings. The purpose of this investigation was to study the distribution of the injected fluid by macroscopic and microscopic techniques. One third of the liquid of the carpules (2% lidocaine with 1:100,000 epinephrine) was replaced with India ink as a marker. Injections were made with a pressure syringe, (Ligmaject) at 90 sites in 12 dogs. Twenty-five control sites were injected with a marked solution without a vasoconstrictor (3% mepivacaine). Seven dogs were killed within 24 h; the others after 5 days. Spread of the ink was studied in undemineralized slices, in three-dimensional cleared specimens, and in histological sections. The solution usually reached the alveolar crest, seeped under the periosteum, and entered into bone marrow spaces alongside vascular channels. The ink spread along the path of least resistance, influenced by the intricacies of anatomical structures and fascial planes, rather than penetrating into the periodontal ligament or in the root canal. In the controls without a vasoconstrictor the spread was more diffuse. Five days postoperatively, carbon particles were present only within macrophages.

Anesthesia, Dental↗

PubMed1994

Periodontal ligament injection in the dog primary dentition: spread of local anaesthetic solution.

The spread of local anaesthetic solution administered with a pressure syringe has not been studied as extensively in young animals having primary or mixed dentitions as in adult animals. The purpose of this investigation was to study the distribution of local anaesthetic solution injected into the periodontal ligament of young dogs. India ink was added to carpules containing 2% lidocaine and 1:100,000 epinephrine, and the spread of solution was examined macroscopically and microscopically. Injections were made with a pressure syringe (Ligmaject) at 58 sites mesial and distal to primary teeth in five dogs aged 3-9 months. Three dogs were killed within 12 hours, the other two after 5 days. Spread of the ink was studied in non-decalcified slabs, in three-dimensional cleared specimens, and in histological sections. The solution usually reached the alveolar bone crest, seeped under the periosteum and alongside vascular channels into bone marrow, reaching natural cavities such as the crypts of tooth buds and the mandibular canal. The ink did not penetrate into the enamel organ or contact the permanent tooth buds. The solution appeared to spread along the path of least resistance, governed by the intricacies of anatomical structures and fascial planes. Therefore the risk of mechanical damage to permanent tooth germs appears to be minimal.

Anesthesia, Dental↗

PubMed1990

Densitometric measurement of radiopacity of Gutta-percha cones and root dentin.

National and international standards require that gutta-percha cones be sufficiently radiopaque to be distinguished from natural structures such as dentin and to permit evaluation of the density of the root canal filling. Discs, 1-mm thick, made from 15 commercial and experimental brands of gutta-percha cones, were tested for their compliance with the requirements. The radiopacity of 1-mm thick root dentin slabs was similarly measured with a photo-densitometer. All radiographs were made on D-speed occlusal film and replicated on E-speed film. The mean radiopacity of the gutta-percha discs on D-speed film was 7.26 mm of aluminum equivalent and 7.53 mm on E-speed film, greatly exceeding the minimal requirement of 3 mm. The difference in the values obtained with the two film types was not significant, suggesting that E-speed films may be used for the test. Dentin slabs were uniform in their radiopacity, equivalent to 1 mm of aluminum, confirming previous findings. In view of complaints of insufficient clinical performance, the present minimal requirement for radiopacity of gutta-percha cones seems too low.

Densitometry↗

PubMed1989

Tubular permeability to calcium hydroxide and to bleaching agents.

Recent reports of clinical cases suggest that cervical root resorption may follow bleaching of endodontically treated teeth. Inflammatory root resorption may be arrested by placement of calcium hydroxide into the root canal. The dentinal tubules are assumed to be a possible route of action for both agents. pH Values of the medium surrounding the tooth after placement of bleaching agents and calcium hydroxide within the root canals were determined in this study. Thirty extracted single-rooted human teeth were divided into three equal groups. The pulp cavity of the experimental teeth was filled with either bleaching agents or calcium hydroxide. In the control group it was left empty. Dipping in paraffin sealed the access cavity and the apical foramina and isolated the teeth except at the cervical root surface. The teeth were placed in vials containing distilled water and the pH of the medium was measured after 1 h, 3 days, and 7 days following renewal of the medium. The level of the pH in the first group increased, indicating that the bleaching agents leaked from the root canal to the medium surrounding the teeth. The pH in other two groups did not change noticeably. The results suggest that bleaching agents may leak from the root canal toward the periodontal tissues but calcium hydroxide does not alkalinize the medium surrounding the teeth. Leakage of the bleaching agents through dentin may, therefore, be considered as a possible etiological factor that initiates an inflammatory process around the teeth that may be followed by cervical root resorption.

Calcium Hydroxide↗

PubMed1989

Life and AH26 as sealers in thermatically compacted gutta-percha root canal fillings: leakage to a dye.

Calcium hydroxide-containing root canal sealers may encourage apical obturation by cementum. Hard-setting bases with calcium hydroxide induce calcification, but set too quickly to permit lateral condensation of gutta-percha. Since thermatic compaction requires less time than lateral condensation, the possibility of using this method with Life as a sealer was investigated. Seventy roots were prepared and filled with gutta-percha using the Engine Plugger for thermatic compaction. In one group of 20 Life was used as a sealer. AH26 was used in another group of 20. The remainder served as controls. Leakage was tested by linear penetration of Procion B Blue dye measured after clearing the teeth. In the Life group the mean dye penetration was 0.575 mm versus 1.025 mm in AH26, but the difference was not statistically significant. The results indicated that Life could be used in thermatic compaction of gutta-percha and that it provided a seal comparable to that obtained with AH26.

Bismuth↗

PubMed1989

Periapical reactions to calcium hydroxide-containing sealers and AH 26 in monkeys.

The long-term effect on periapical healing (8-14 months) of CRCS and Sealapex was compared with that of AH 26. Vital pulpectomy and root canal filling by the hybrid thermomechanical method were performed in teeth of 3 young monkeys. Ten roots with CRCS, 10 with Sealapex and 7 roots with AH 26 were examined after demineralization and routine histological processing. Hematoxylin and eosin and Brown & Brenn staining for micro-organisms were employed. Mild to severe inflammatory lesions were found at the apical foramina of the roots filled with AH 26 and CRCS. Most of the Sealapex specimens showed no inflammatory cells, except macrophages with sealer particles. A striking finding was a tendency towards apical obliteration with calcified tissue in roots filled with Sealapex, apparently following resorption of the sealer. Such a tendency was seldom observed with the other sealers. However, both AH 26 and Sealapex were irritating for a long time when pushed into bone. Despite the interesting results with Sealapex, additional research is needed before its use can be unconditionally recommended. This sealer has not yet been tested in infected cases and its ability to be resorbed, which is an advantage when it precedes replacement by calcified tissue, may become a disadvantage if it is not followed by apical obliteration.

Animals↗

PubMed1988

Correction of mucosal defects of periapical origin with periodontal surgical techniques.

Periapical lesions usually heal after successful root canal therapy. Persistent apical-oral communications may be due to anatomic and pathologic features that were originally linked to the endodontic cause of the lesion. One such factor is close proximity of the root apex to the oral mucosa. These defects necessitate corrective surgical intervention similar to techniques used in periodontal surgery. Four cases involving young female patients are described. These defects occurred in teeth that did not complete their maturation before necrosis of the pulp set in.

Adolescent↗

PubMed1988