SEARCH · Search PubMed
Results for “Dentin Permeability”
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.
[The environmental factor in the etiology and origin of dental caries].
Explore the source record for details and available documents.
Smear layer: physiological considerations.
Explore the source record for details and available documents.
Microbiology and immunopathology of pulpal and periapical infections. Part I.
Explore the source record for details and available documents.
[Biophysical study on dental tissue changes due to the local application of strontium].
Explore the source record for details and available documents.
Comparison of patient-perceived postcementation sensitivity with glass-ionomer and zinc phosphate cements.
Numerous investigators have reported patients' postcementation sensitivity with glass-ionomer luting agents. This information has been predominantly anecdotal and unsupported by data. This paper reports on the actual perceptions of patients who had restorations cemented with both glass-ionomer and zinc phosphate luting agents. Forty-five patients were randomly selected and received two cast restorations, one cemented with glass-ionomer cement and the other with zinc phosphate cement, also by random assignment. After 1 week, patients returned to complete a self-administered evaluation of perceived sensitivity. Neither luting agent resulted in greater sensitivity when used according to its manufacturer's instructions.
Pulpal response to adhesive resin systems applied to acid-etched vital dentin: damp versus dry primer application.
A number of studies have reported that acid etching of dentin is toxic to the cells of the odontoblastic layer and dental pulp. Other studies report that pulpal inflammation is a consequence of bacterial microleakage. The purpose of this study was to observe the degree of pulpal healing after pretreatment of vital dentin prior to placement of All-Bond and Scotch-bond 2 composite resin adhesives. Zinc oxide-eugenol cement and an acidic cement were employed as controls. One hundred twelve Class V nonexposed cavity preparations were placed throughout the dentitions of five healthy adult rhesus monkeys and observed at 3, 25, and 80 days. Various dentinal pretreatment procedures were employed. The All-Bond Universal primer system was placed on air-dried vital dentin in 23 cavities and on damp vital dentin in 27 cavities. Scotchbond 2 was placed as per manufacturer's instructions. All treatment procedures, materials, and times were represented in all animals. Placement of silicate cement resulted in the most severe pulpal responses at all time periods. Stained bacterial profiles in the remaining dentin on the axial walls of inflamed control pulps were associated with severe pulpal inflammation. These results indicate that acid etching of vital dentin does not impair pulpal healing in deep Class V cavities.
Adhesive interface between resin and etched dentin of cervical erosion/abrasion lesions.
The interfacial structure between an adhesive composite resin and the dentinal walls of cervical erosion/abrasion lesions etched with 37% phosphoric acid gel for 60 seconds was investigated. Almost all dentinal tubules were occluded with rod-like structural depositions that remained undissolved even after acid conditioning. The hybrid layer between the adhesive resin and surface-demineralized dentin was found to be 0.3 to 3 microns, much thinner than that routinely found in either normal dentin or cariously affected dentin. The hybrid layer was thinnest at the occlusal walls of the cavity where the dentinal tubules run parallel to the cavity surface. The bond strength of adhesive resin to these areas may differ from that to intact normal dentin.
Hybridizing dentin--a new concept in treating dentinal surfaces.
Explore the source record for details and available documents.
Evaluation of a new dentifrice for the treatment of sensitive teeth.
A dentifrice containing 5% potassium nitrate, 1.3% soluble pyrophosphate, 1.5% polyvinylmethyl ether and maleic acid (PVM/MA) copolymer and 0.243% sodium fluoride in a silica base (Sensitive/Tartar Control) has been developed to concomitantly control tartar, caries and dentinal hypersensitivity. In vitro and animal studies show that the fluoride in this product effectively inhibits formation of enamel and dentine caries. In vitro studies also demonstrate that this dentifrice effectively reduces hydraulic conductance by occluding dentine tubules with a mixed surface deposit of copolymer and silica. Using an in vitro model that simulates in vivo conditions, this dentifrice also allows a rapid penetration of potassium nitrate through the dentine matrix. These findings demonstrate a correlation under in vivo conditions between the occlusion of dentine and the ability to deliver topically applied agents to target sites within or below dentine. The results indicate that this new dentifrice should provide multiple clinical therapeutic benefits including controlling tooth decay and tartar formation, and reducing and preventing dentinal hypersensitivity.
Partial pulpotomy: another treatment option for cariously exposed permanent molars.
Explore the source record for details and available documents.
The Gluma bonding system: a clinical evaluation of its various components for the treatment of hypersensitive root dentin.
This study investigated the desensitizing effect of topically-applied Gluma on sensitive cervical erosion lesions. A total of 46 teeth exhibiting moderate to severe sensitivity to cold and instrumentation, in 15 patients, were included in the study. Mildly sensitive teeth and teeth with cervical caries lesions were excluded from the study. After each tooth was isolated with rubber dam, investigators applied cold air, as well as tactile stimuli using an explorer, and recorded the baseline responses. Nine of the 46 teeth then received Gluma primer only (group 1), 15 received cleanser followed by primer (group 2), 15 received cleanser followed by primer and sealer (group 3), and seven received a placebo (group 4). After two weeks, the teeth in group 4 were randomly placed in one of the other three groups. The responses of the teeth in each group to various stimuli were recorded immediately after the application of test materials, and subsequently at one week, two weeks, one month, three months, six months and one year. Statistical analysis indicates that the three treatment groups all showed significant differences compared to the untreated control group (p < .001). A reduction of sensitivity was noted immediately after primer, cleanser-primer, or cleanser-primer-sealer was applied. Treatment groups 2 and 3 demonstrated less sensitivity than group 1 (p = .02; p = .03, respectively). At the one-year recall, the observed order of treatment effectiveness by group was 2, 3, 1. In approximately 50 per cent of the teeth treated in the study, remission of sensitivity was seen after one year. All of the remaining teeth exhibited some relief of sensitivity. The treatments' success was found to be inversely proportional to the severity of the initial response.
Dentin desensitizing agents: SEM and X-ray microanalysis assessment.
PURPOSE: To evaluate the effect of four proprietary dentin desensitizing agents on dentin tubular occlusion, chemical composition changes on the dentin surface, and the effect of saliva and toothbrushing on these agents. MATERIALS AND METHODS: Fifty dentin discs, obtained from 50 freshly extracted human premolar and molar teeth were used in this study. These were divided into five groups of 10 discs each. Five discs from each group were treated with the desensitizing agents, viewed under the SEM and subjected to energy dispersive X-ray analysis. The other five discs were treated with the desensitizing agents, immersed in artificial saliva, subjected to simulated toothbrushing equivalent to 3 weeks of normal brushing and viewed under the SEM. The agents studied were Sensodyne Dentin Desensitizer, Therma-Trol Desensitizer Gel, Gluma Desensitizer and All-Bond DS. RESULTS: The Kruskal-Wallis test followed by the Wilcoxon signed-rank test showed that Sensodyne Dentin Desensitizer exhibited the greatest amount of tubular occlusion among the unbrushed samples, followed by Therma-Trol Desensitizer Gel, Gluma Desensitizer and All-Bond DS (P < 0.05) in that order. Toothbrushing increased tubular occlusion in all cases except the Sensodyne Dentin Desensitizer treated samples.
An investigation of the effect of a desensitizing dentifrice on dentinal tubules in vitro and in vivo.
The effect of Sensodyne dentifrice, which contains strontium chloride hexahydrate, on the occlusion of dentinal tubules was studied in vivo and in vitro. Eight premolar teeth scheduled for extraction for orthodontic purposes were used. Four of the teeth were extracted before Sensodyne application (in vitro). The other four teeth were treated in vivo and then extracted. A patch of enamel was removed from all the teeth to expose the dentinal surfaces, and the smear layer over the exposed area was removed. In the in vivo test, the patients were instructed to brush their teeth for 1 minute, twice a day, for 2 weeks. The teeth were then extracted and kept in distilled water until examined by scanning electron microscope. The in vitro teeth were brushed in the same manner and kept in distilled water between brushings. Most of the in vitro dentinal tubules were found to be open, whereas most of the in vivo dentinal tubules were occluded.
Dentin-predentin complex and its permeability: pathology and treatment overview.
This review paper focuses attention on tissue changes which may take place in dentin and on localized alterations in tissue formation in the predentin area. A number of reaction patterns has been described in dentin affecting both the inorganic and organic components. Dentinal tubules may become partly or completely obturated by growth of the peritubular dentin. Precipitation of mineral salts within the tubules, which may be a reprecipitation of minerals from adjacent demineralized dentin, represents a fundamentally different mode of obturation of dentinal tubules. Initially, demineralization selectively affects the peritubular dentin. If dentin is exposed to the oral environment, the surface layer may become hypermineralized. The surface layer of dentin, exposed by grinding, becomes covered by a smear layer. Displacement of the contents of the tubules or of the odontoblasts is a characteristic change in the organic components. Odontoblast destruction or degeneration will lead to a lack of, or reduced, predentin formation. Changes in the protein components which lead to alterations in dentin permeability have also been reported. The structure of the interface between dentin and localized formations of irregular secondary dentin varies considerably. If there is no tubular communication between primary and secondary dentin, the interface will act as an impermeable barrier. Changes in dentin, including irregular secondary dentin formation, affect the permeability of the tissue. Such changes are clinically important for the outcome of all types of restorative work performed on vital teeth.
Sterilization of human teeth: its effect on permeability and bond strength.
Extracted human teeth were randomly divided into three groups. Group 1 teeth were untreated and served as controls. Group 2 teeth were sterilized in a steam autoclave. Group 3 teeth were sterilized by exposure to ethylene oxide gas. Crown segments were then prepared from these teeth by resection of the roots at the CEJ and the occlusal enamel to expose a flat occlusal plane of dentin. The permeability of the dentin was determined to be similar in all three groups. The shear bond strength of Prisma Universal Bond 3 and C&B Metabond was also similar in all groups indicating that sterilization of teeth does not alter dentin permeability or bond strength.
Influence of sodium hypochlorite on the permeability and structure of cervical human dentine.
The effect of 5% sodium hypochlorite and 35% hydrogen peroxide on dentine samples in vitro was investigated. It was demonstrated that both 5% NaOCl and 35% H2O2 depletes the dentine, which can be recorded as weight loss. Sodium hypochlorite removes approximately 14% of dry weight from dentine samples in 24 h; hydrogen peroxide is half as destructive. The hydraulic conductance (Lp) of dentine after treatment with NaOCl is increased over 100%. It is suggested that the use of high concentrations of sodium hypochlorite during root canal treatment may negatively affect the integrity of the root canal wall thereby allowing increased access of caustic bleaching fluids to cervical vital tissues.
[Permeability of formocresol into the root dentin and its effects on the periodontium in dogs].
Explore the source record for details and available documents.