Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “DENTAL CAVITY LINING”

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 595 records · Page 33Linked to original sources
PubMed1978

Human pulp response to a new composite system. Vytol composite restorative and bonding agent.

A new two-paste composite system (Vytol and Vytol Bonding Agent) was evaluated to establish its level of pulpal response in human teeth and to determine whether a calcium hydroxide base is required. Class V cavity preparations were cut in seventy-two teeth of ten male patients whose ages averaged 52.5 years. The teeth were restored and extracted at 1 to 7 days, 12 to 14 days, and 47 to 56 days. Histologic evaluation indicated that the unlined Vytol System reacted very similarly to other commercially available composite restorative materials and that a calcium hydroxide base is effective in reducing or eliminating adverse pulp responses.

Acid Etching, Dental↗
PubMed1981

Pulp response in sound and carious teeth: a pilot study.

This article describes a pilot investigation in which the response of the pulps in both sound and carious rat molar teeth to traumatic exposure and treatment with three different compounds was assessed. Two of the compounds appeared to give a more favorable response in carious teeth. These results are discussed, and future experiments described.

Animals↗
PubMed1988

The effect of varnish and pit and fissure sealants on the sealing capacity of retrofilling techniques.

Freshly extracted teeth with single canals were instrumented and filled with laterally condensed gutta-percha and sealer. After obturation, the tooth apices were treated with various retrograde techniques. The sealing ability of these techniques, namely laterally condensed gutta-percha, heat-sealed gutta-percha, and silver amalgam retrofilling, was compared on the basis of dye penetration. The apical foramen of the treated canals was then coated with different sealing materials--HelioSeal (light-activated sealant), Delton pit and fissure sealant (chemically activated sealant), and varnish--to examine their effect on the leakage resistance of these materials. Statistical analysis indicated that laterally condensed gutta-percha, as well as retrograde amalgam filling, produced a statistically significantly better seal than heat-sealed gutta-percha. Coating of the apical foramen with different sealing materials showed that HelioSeal had significantly improved the sealing capacity of all the materials tested at each time period. Delton pit and fissure sealant did not increase the sealing ability in the first week. However, this material has significantly improved the sealing ability after the first week. On the other hand, sealing of the apical foramen with varnish did not produce any significant change in the sealing capacity of the filling materials. Finally, dye penetration around all the filling and retrofilling materials, in the presence or absence of the apical seal, continued and increased with time. However, root canals sealed with Helioseal consistently showed the least amount of apical leakage of all the canals tested.

Apicoectomy↗
PubMed1993

Evaluation of the apical seal of amalgam retrofillings with the use of a root canal sealer interface.

The apical seal of amalgam retrograde fillings was evaluated in 86 extracted teeth. The experimental groups included retrofillings of amalgam alone, amalgam with a cavity varnish interface, and amalgam with a root canal sealer interface. After a 3-month immersion of the teeth in Higgins ink and subsequent clearing process, statistical analysis of ink penetration measurements showed significantly less leakage (p < 0.001) around amalgam retrofillings when using a root canal sealer as an interface between the retrograde cavity preparation and the condensed amalgam.

Dental Alloys↗
PubMed1989

Effects of bonding agent types and incremental techniques on minimizing contraction gaps around resin composites.

In this in vitro study, large rectangular cavities were prepared on the proximal surfaces of human premolars with cervical margins placed beyond the cemento-enamel junction. Before the insertion of resin composite, the cavity walls were treated with Bowen's system, Scotchbond, or Gluma combined with different bonding agents. Various incremental techniques were tested. The contraction gap was determined by use of the resin impregnation technique: After polymerization shrinkage, a low-viscosity resin with a fluorescent additive was applied to the cervical and occlusal margins to penetrate the contraction gap. After being ground, the width of fluorescent resin could be measured with a microscope. All combinations of materials and techniques produced contraction gaps at the cervical wall. The range for mean width of the impregnated gap at the cervical wall was from 5 to 13 microns. The lowest mean value was obtained for Gluma in combination with Clearfil Bonding Agent. Placement of the composite in two increments significantly reduced the gap width. No reduction was achieved when a three-step insertion technique was used.

Composite Resins↗
PubMed1990

Effect of water sorption and thermal stress on cavity adaptation of dental composites.

The effect of water sorption of composite and thermal stress on the marginal adaptation to the dentin cavity wall was evaluated by measurement of the gap width between composite fillings and the dentin cavity wall. The wall of a cylindrical dentin cavity prepared in the proximal surface of extracted human molars was cleaned with neutralized 0.5 M EDTA and pre-treated with one of three experimental dentin primers [35% hydroxyethyl methacrylate (HEMA), 35% HEMA containing 5% glutaraldehyde, and 35% glyceryl methacrylate]. A light-activated composite (Silux, 3M Co., St. Paul, MN) was used to fill the cavity after application of a bonding agent (Clearfil New Bond, Kuraray Co., Osaka, Japan). The marginal gap width was measured after the specimens were immersed in water and thermal-cycled. The initial contraction gap of the tested bonding systems was closed completely by the water sorption of the composite for six hours, and such a marginal adaptation was not interrupted by 60 thermal cycles between 10 and 45 degrees C. Among the dentin primers tested, only the 35% aqueous solution of glyceryl methacrylate mediated gap-free fillings in all specimens.

Composite Resins↗
PubMed1990

Surface reactions of adhesives on dentin.

The purpose of this study was to characterize changes in the surface chemistry of dentin following various adhesive treatments. The coronal parts of sound freshly extracted third molars were cross-sectioned over the pulp chambers, each producing a pair of dentin samples which were polished to 600 grit and cleaned with 3% H2O2. The first sample of each pair was used as a control, while the second one was subjected to one of the following adhesive treatments: (a) Gluma Cleanser, (b) Tenure Conditioner, (c) Scotchprep, (d) Gluma Cleanser/Gluma Primer, (e) Tenure Conditioner/Tenure Solution A&B, or (f) Scotchprep/Scotchbond 2 Adhesive. The treated samples paired with their respective controls were studied by small-area ESCA spectroscopy. Three areas of 1.0 mm in diameter randomly chosen on each sample were analyzed by survey and C1s, O1s, N1s high-resolution spectra. The samples from groups d, e, and f were additionally subjected to argon-ion-depth profiling of the uppermost 2-nm layer at 0.5-nm intervals. According to the results, treatment modes a, b, and c caused the reduction of carbonates and increased the -NH/NH2 ratio. Treatments a and c increased the alcohol groups, while treatments b and c increased the carbonyl and ether groups. All these changes were in comparison to the reference dentin specimens. Dentin treatment with d, e, and f induced a complex in depth distribution of the C, N, O binding states. The energy shifts detected do not indicate primary bonding of the tested adhesives to the dental substrate.

Adhesives↗
PubMed1991

Evaluation of various forms of calcium hydroxide in the monitoring of microleakage.

Calcium hydroxide has been shown to be an effective medium for the in vivo microleakage testing of amalgams. The purpose of this study was to determine the relative effectiveness of several forms of calcium hydroxide in the measurement of this clinical problem. It was also the purpose of this study to determine whether a relationship exists between the pH of the Ca(OH)2 liner and its ability to detect microleakage. Standardized Class V preparations were generated on the buccal surfaces of extracted molars. The axial walls of the preparations were based either with Dycal, Dycal VLC, Pulpdent Liquid, or pure Ca(OH)2. A series of teeth without a calcium hydroxide base served as the negative control. All teeth were restored with a spherical amalgam and kept in de-ionized water. The surfaces of the restorations were then subjected to 20 mL of 2 degrees C water for a period of one min. After three min, a color-indicating pH paper was positioned over the restored area for detection of the presence of hydroxyl ions at the amalgam/tooth interface. Regardless of the form of calcium hydroxide, all indicated extensive microleakage immediately after insertion of the restoration. In all cases, the number of samples generating positive results for leakage decreased over a period of time. The rate of decrease, however, was substantially dependent upon the form of calcium hydroxide used as well as its pH. The reagent grade of Ca(OH)2 generated the greatest percentage of positive results for the longest duration.

Calcium Hydroxide↗
PubMed1991

Comparison of the sealing ability of four cavity varnishes: an in vitro study.

The purpose of this study was to test and to compare, in vitro, the sealing ability of four different cavity varnishes used to minimize the marginal leakage of amalgam fillings. For this purpose, a model was developed in order to avoid quality-deteriorating effects (such as condensation forces used during placement of amalgam) and temperature changes. In this model, raw ceramic disks were used instead of dentin. The four varnishes showed significant reducing effect on the penetration of the dye (Methylene Blue) compared with the control. There was no cavity varnish with optimal sealing.

Analysis of Variance↗
PubMed1992

Effect of water-soluble photoinitiator on the adhesion between composite and tooth substrate.

The effectiveness of a water-soluble photoinitiator in a dentin primer was examined by measuring the tensile bond strength between the composite and tooth substrate treated with the primer. The water-soluble photoinitiator, 2-hydroxy-3-(3,4 dimethyl-9-oxo-9H-thioxanthen-2-yloxy)-N,N,N-trimethyl-1- propanaminium chloride (QTX) was dissolved into an aqueous solution of methoxy-nonaethyleneglycol monomethacrylate (M9G) or poly-N-vinylpyrrolidone (PNVP), and these aqueous solutions were used as primers. The combination of 0.5 M EDTA pretreatment and 1% QTX -35% PNVP aqueous solution priming produced the highest bond strength. A mixture of dentin fractures and interfacial failure between the dentin and the resin was observed in the test specimen. This dentin priming combination was also effective in improving the bond strength to enamel pretreated with EDTA.

Analysis of Variance↗
PubMed1992

Inhibition of microbial adherence and growth by various glass ionomers in vitro.

This study measured the in vitro inhibition of growth and adherence of five oral bacteria by glass-ionomer materials. Disks were prepared from two cavity liners and four restorative class materials, by use of Teflon plates with circular wells, five mm wide and two mm deep. The bacterial species tested included: A. viscosus, S. mitis, S. mutans, L. casei, and S. sanguis. Growth inhibition studies were performed by the spreading of 0.1 mL of standardized inocula over agar plates produced with selective media, followed by the direct application of glass-ionomer disks onto the agar. On other plates, disks were placed onto uninoculated agars for 48 h, followed by bacterial inoculation. All agar plates were incubated under optimal growth conditions for each bacterial species. The four restorative materials were also placed aseptically into sterilized bovine incisors and placed into sucrose containing broth media, inoculated with S. mutans for three days. Adhering materials were disclosed and scored. An ion-exchange electrode was used to measure fluoride release over a seven-day period for all six glass ionomers. The two cavity liners and two of the restorative materials produced the largest growth inhibition zones by direct contact. No growth inhibition occurred when the specimens were allowed to come into contact with the agars prior to inoculation. All four restorative materials reduced bacterial accumulations on enamel surfaces by over 80%. Elevations in short-term fluoride release levels were positively correlated with growth inhibition.

Actinomyces viscosus↗
PubMed1993

Pulpal response to a new light-activated fluoride releasing liner.

The purpose of this study was to investigate the degree of pulp irritation of a newly developed light-activated fluoride-releasing adhesive resin liner using canine teeth compared to the amount caused by a negative control, zinc oxide eugenol cement (ZOE), and a positive control, silicate cement (silicate). In the cases of unexposed pulp, this experimental liner showed none, slight or moderate pulpal changes at 3 d postoperatively. At 30 and 90 d, no pulpal response to the experimental liner was detected in almost all cases. These findings were similar to the ZOE and better than the silicate. There was less evidence of pulpal irritation produced by the experimental liner. This material seems to be safe to the pulp under the conditions of this study.

Analysis of Variance↗
PubMed1993

Shear bond of resin cement to post-cured hybrid composites.

Various surface treatments affected the shear bond strength of a dual-cured resin cement to a post-cured composite. Disks of post-cured composite inlay 2.0 mm thick by 10.0 mm in diameter, were mounted in acrylic cylinders. Various surface treatments were tested including: 1) smooth material; 2) treated by sandblasting (air abrasion); 3) sandblasting and etching with hydrofluoric acid (HF); 4) sandblasting and silane priming; 5) sandblasting, HF etching and silane priming; 6) HF etching alone; 7) HF etching and silane priming; and 8) silane priming alone. Specimens of dual-cured cement, 4.0 mm in diameter, were light-cured onto the prepared surfaces. The samples were stored in water at 37 degrees C for 7d before shear bond testing. The highest mean shear bond strengths were achieved for specimens with the following surface treatments: 1) by a combination of sandblasting, HF etching and silane priming; 2) sandblasting and HF etching; and 3) sandblasting and silane priming. Most bond failures in these groups were cohesive within the post-cured composite inlay disks. The bond strengths of the specimen in other groups were significantly lower and bond failures were mainly adhesive at the interface between the disk of post-cured composite and dual-cured resin cement.

Acid Etching, Dental↗
PubMed1993

Thermal conductivity of cement base materials.

This study was designed to determine the most efficient dentin-cement-restorative material system to minimize temperature changes from either a hot (58 degrees C) or cold (4 degrees C) source. Extracted human molar teeth were used to conduct the experiment utilizing a standard Class I occlusal preparation 3.5 mm in diameter with a remaining dentin thickness of 0.5 or 1.0 mm and a control dentin thickness of 2.0 mm. A bi-electrode thermocouple was utilized with one thermocouple mounted on the roof of the pulp chamber and the other on the occlusal surface of the specimen. The cements investigated were zinc oxide and eugenol (ZOE), zinc phosphate (ZP), glass ionomer (GI), and zinc polycarboxylate (ZPC) with a thickness of either 0.5 mm or 1.5 mm. Statistical analysis consisted of a one-way analysis of variance followed by a multiple means comparison test. For heated specimens consisting of cement and dentin only, ZOE was the least effective in limiting temperature change. When cold was applied, ZOE was the most effective. Statistically for cold application, the other three cements, ZP, GI and ZPC, and 2.0 mm of dentin were the same for limiting temperature change. When amalgam was used to restore the tooth, ZOE and GI were most effective in limiting temperature change for cooled teeth. For heated teeth, all the cements were identical except for ZOE, which was the least effective. For composite restored teeth, all cements and dentin were identical in limiting temperature changes for either heating or cooling.

Analysis of Variance↗
PubMed1993

The effect of glass ionomer liners in lowering pulp temperatures during composite placement, in vitro.

New restorative systems allow for more esthetic restorations, but may cause adverse pulp tissue reactions due to either physical or chemical effects. This study evaluated the effect of glass ionomer liners in limiting temperature rise during composite placement with visible light-cure lamps. Neither chemical or light-cured glass ionomer liners limited the amount of pulp chamber temperature rise. Exposure time of the light-cure lamps played the greatest role in pulpal temperature rise regardless of glass ionomer liner of composite. Visible light-cure lamps varied in the amount of heat emitted.

Analysis of Variance↗
PubMed1993

Adhesion and microleakage tests of a new dentin bonding system.

Adhesion to dentin and microleakage of a new dentin bonding system was studied. The new system includes a low viscosity lightly filled Bis-GMA based resin liner which is placed between the phosphate ester-containing adhesive layer and the composite. This system was compared to dentin bonding agents based on: 1) HEMA and Bis-GMA and 2) PMDM and NTG-GMA. The phosphate ester system was used with and without the low viscosity resin. Each system was used with its corresponding posterior composite. All groups were tested by shear and tensile bond testing immediately and up to 6 mon after bonding. Microleakage of the three systems was tested in Class V restorations by dye penetration. The results of the shear and tensile tests indicated that significant changes within groups occurred with time, and significant differences appeared between groups at various times. The use of low viscosity resin with the phosphate ester system resulted in decreased leakage. The amount of leakage observed was related to early shear bond strength. This study suggests that the properties of the layer immediately adjacent to the adhesive may affect the performance of the system.

Adhesiveness↗