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PubMedDate not supplied

Indirect pulp treatment: in vivo outcomes of an adhesive resin system vs calcium hydroxide for protection of the dentin-pulp complex.

PURPOSE: The purpose of this prospective and randomized in vivo study was to compare the clinical and radiographic outcomes of an adhesive resin system vs a calcium hydroxide liner for protection of the dentin-pulp complex of primary molars treated with indirect pulp treatment. METHODS: Forty-eight primary molars with deep occlusal caries, but without preoperative signs and symptoms of irreversible pulpitis, received indirect pulp treatment and were restored with a composite resin (Z100). The teeth were randomly divided into 2 groups according to the material used for protection of the dentin-pulp complex: (1) adhesive resin system (Scotchbond MultiPurpose); and (2) calcium hydroxide liner (Dycal). These teeth were evaluated clinically and radiographicaly for 2 years. RESULTS: After 2 years, 83% (19/23) of the teeth treated with calcium hydroxide and 96% (24/25) of teeth treated with only the adhesive resin system presented a successful outcome, as determined by clinical and radiographic examination. Interradicular and/or periapical lesions were the most predominant signs of treatment failure, since 3 out of 23 teeth treated with calcium hydroxide and 1 out of 25 teeth treated with only adhesive resin presented this outcome. One tooth treated with the calcium hydroxide liner was diagnosed with internal root resorption at the 18-month examination. Of the 5 teeth diagnosed from radiographs as a failure of the indirect pulp treatment, none presented clinical signs/symptoms of pulpitis or necrosis such as the presence of fistula, enhanced tooth mobility, or pain. CONCLUSIONS: This study demonstrates that protection of the dentin-pulp complex of primary molars with an adhesive resin system results in similar clinical and radiographic 2-year outcomes as compared to calcium hydroxide when indirect pulp treatment is performed in Class I composite restorations.

Calcium Hydroxide↗
PubMedDate not supplied

The effect of silica coating on the resin bond to the intaglio surface of Procera AllCeram restorations.

OBJECTIVES: This study investigated the influence of a silica-coating method on the resin bond of two different resin composite cements to the intaglio surface of Procera AllCeram densely sintered, high-purity, alumina ceramic restorations after long-term storage and thermocycling. METHOD AND MATERIALS: Densely sintered alumina ceramic specimens were fabricated with the intaglio surface of the Procera AlICeram coping and randomly divided into five adhesive groups (100 total specimens). Resin composite cylinders were bonded either to the untreated or to the tribochemical silica/silane-coated ceramic surface with either a conventional Bis-GMA resin cement or a resin composite containing an adhesive phosphate monomer (Panavia 21) in combination with their corresponding bonding/silane coupling agents. Panavia was also used without silanization to the untreated ceramic surface (control). Subgroups of 10 specimens were stored in distilled water for either 3 (baseline) or 180 days prior to shear bond strength testing. The 180-day samples were subjected to repeated thermocycling for a total of 12,000 cycles. Data were analyzed with one-way analysis of variance and Tukey's multiple comparison. RESULTS: Silica coating significantly increased overall bond strength to Procera AllCeram. RelyX ARC and silica coating revealed the highest bond strength at baseline. Long-term storage and thermocycling significantly decreased overall bond strength. Two groups revealed the significantly highest bond strength values after artificial aging: Panavia 21 with its silane/bonding agent to the original ceramic surface and Panavia 21 to the silica-coated ceramic surface. CONCLUSION: The use of a resin composite containing an adhesive phosphate monomer either in combination with a silane coupling/bonding agent or after tribochemical silica/silane coating revealed the highest long-term shear bond strength to the intaglio surface of Procera AllCeram restorations.

Aluminum Oxide↗
PubMedDate not supplied

A 10-year prospective evaluation of CAD/CAM-manufactured (Cerec) ceramic inlays cemented with a chemically cured or dual-cured resin composite.

PURPOSE: The present follow-up study was carried out to evaluate the performance of Class II Cerec inlays after 10 years of clinical service. MATERIALS AND METHODS: Sixty-six Class II CAD/CAM ceramic inlays were placed in 27 patients. Each patient received at least one inlay luted with a dual-cured resin composite and one inlay luted with a chemically cured resin composite. At the 10-year recall, 25 (93%) patients with 61 (92%) inlays were available for evaluation using a slight modification of the USPHS criteria. RESULTS: Fifty-four (89%) of the 61 inlays reevaluated still functioned well at the 10-year recall. During the follow-up period, seven (11%) of the inlays required replacement because of: four inlay fractures, one cusp fracture, endodontic problems in one case, and postoperative symptoms in one case. All the replaced inlays had been luted with the dual-cured resin composite. The fractured inlays were all placed in molars. The estimated survival rate after 10 years was 89%, 77% for the dual-cured resin composite-luted inlays and 100% for the chemically cured resin composite-luted ones. The difference was statistically significant. CONCLUSION: Patient satisfaction with and acceptance of the Cerec inlays were high, and the performance after 10 years of clinical service was acceptable, especially regarding the inlays luted with the chemically cured resin composite. The properties of the luting agents seem to affect the longevity of the type of ceramic inlays evaluated.

Adult↗
PubMed2004

Influence of adhesive system and placement technique on microleakage of resin-based composite restorations.

PURPOSE: To analyze the influence of two placement techniques and two adhesive systems on the marginal microleakage of Class II resin-based composite restorations using different resin composite materials. MATERIALS AND METHODS: Two hundred standardized Class II cavities (5 mm x 3 mm x 1.5 mm) were cut in human premolars and restored using five resin composite materials (A.L.E.R.T.-AL, Solitaire-SO, SureFil-SU, Filtek A110-A, and Z100-Z), two adhesive systems (Bond 1-B1 and Etch & Prime 3.0-EP), and two placement techniques (incremental or bulk). Specimens were thermocycled (700 cycles, 5 degrees - 55 degrees C, 1 min dwell time), immersed in 0.5% methylene blue solution for 4 h, and sectioned longitudinally to evaluate the extent of microleakage. Data were submitted to statistical analysis using the Kruskal-Wallis test. RESULTS: It was observed that both adhesive systems presented similar results (p > 0.05), and neither achieved complete marginal sealing. The bulk placement technique led to greater microleakage than the incremental technique (p < 0.001). Restorations prepared using SO resin composite showed greater microleakage than those performed using Z or AL materials. However, SO obtained similar values of microleakage when compared to SU and A materials. CONCLUSION: The use of incremental placement technique resulted in less microleakage for Class II resin-based composite restorations. No difference was observed among adhesive systems regarding prevention of marginal dye penetration. Furthermore, the type of resin composite material employed for restoration may have an influence on the extent of microleakage.

Bicuspid↗
PubMedDate not supplied

Microtensile dentin bond strength of self-etching resins: effect of a hydrophobic layer.

In this study, the microtensile bond strength of resin composites to dentin was determined when hydrophilic self-etching resins were used with and without an additional layer of a more hydrophobic adhesive. Included were three single-step self-etching adhesives, Adper Prompt L-Pop (3M ESPE), iBond GI (Heraeus Kulzer, Inc) and Xeno III (Caulk/Dentsply), and as a negative control, UniFil Bond (GC America), a self-etching primer with a separate adhesive. Each product was evaluated using a hybrid resin composite from its respective manufacturer, and each was used as directed and then used with an added layer of a more hydrophobic resin from its respective manufacturer. Testing was performed after 72 hours using a "non-trimming" microtensile test at a crosshead speed of 0.6 mm/minute. When the products were used according to manufacturers' directions, iBond had a significantly higher bond strength to dentin than the other three products (p<0.001), which were not significantly different from each other. For the three self-etching adhesive systems, the addition of a layer of a more hydrophobic resin produced significantly higher bond strengths to dentin (p<0.001), while no significant effect was found for the self-etching primer (p=0.40). A significant interaction was found between the variables product and adhesive treatment. The TEM evaluation of Prompt L-Pop and iBond demonstrated reduced nanoleakage with the additional resin layer.

Composite Resins↗
PubMed2006

Bond strength of a resin cement to high-alumina and zirconia-reinforced ceramics: the effect of surface conditioning.

PURPOSE: The aim of this study was to evaluate the effect of two surface conditioning methods on the microtensile bond strength of a resin cement to three high-strength core ceramics: high alumina-based (In-Ceram Alumina, Procera AllCeram) and zirconia-reinforced alumina-based (In-Ceram Zirconia) ceramics. MATERIALS AND METHODS: Ten blocks (5 x 6 x 8 mm) of In-Ceram Alumina (AL), In-Ceram Zirconia (ZR), and Procera (PR) ceramics were fabricated according to each manufacturer's instructions and duplicated in composite. The specimens were assigned to one of the two following treatment conditions: (1) airborne particle abrasion with 110-microm Al2O3 particles + silanization, (2) silica coating with 30 microm SiOx particles (CoJet, 3M ESPE) + silanization. Each ceramic block was duplicated in composite resin (W3D-Master, Wilcos, Petrópolis, RJ, Brazil) using a mold made out of silicon impression material. Composite resin layers were incrementally condensed into the mold to fill up the mold and each layer was light polymerized for 40 s. The composite blocks were bonded to the surface-conditioned ceramic blocks using a resin cement system (Panavia F, Kuraray, Okayama, Japan). One composite resin block was fabricated for each ceramic block. The ceramic-composite was stored at 37 degrees C in distilled water for 7 days prior to bond tests. The blocks were cut under water cooling to produce bar specimens (n = 30) with a bonding area of approximately 0.6 mm2. The bond strength tests were performed in a universal testing machine (crosshead speed: 1 mm/min). Bond strength values were statistically analyzed using two-way ANOVA and Tukey's test (< or = 0.05). RESULTS: Silica coating with silanization increased the bond strength significantly for all three high-strength ceramics (18.5 to 31.2 MPa) compared to that of airborne particle abrasion with 110-microm Al2O3 (12.7-17.3 MPa) (ANOVA, p < 0.05). PR exhibited the lowest bond strengths after both Al2O3 and silica coating (12.7 and 18.5 MPa, respectively). CONCLUSION: Conditioning the high-strength ceramic surfaces with silica coating and silanization provided higher bond strengths of the resin cement than with airborne particle abrasion with 110-microm Al2O3 and silanization.

Air Abrasion, Dental↗
PubMed2006

Influence of composite resin consistency and placement technique on proximal contact tightness of Class II restorations.

PURPOSE: To investigate the influence of composite resin consistency and placement technique on proximal contact tightness of Class II composite resin restorations. MATERIALS AND METHODS: A manikin model (KaVo Dental) was used with an artificial first molar in which a standardized MO preparation was ground. This preparation was duplicated 360 times. Cavities were restored using Clearfil Photo Bond (Kuraray) combined with one of three composite resins of different consistencies: a low-viscosity (X-Flow, Dentsply), a medium-viscosity (Clearfil AP-X, Kuraray) and a high-viscosity composite (Tetric Ceram HB, Ivoclar Vivadent). Each composite was combined with 6 different matrix systems and separation techniques (n = 20). Groups 1 and 2: precontoured metal circumferential matrix (KerrHawe 1101-c) in a Tofflemire retainer combined either with hand instrument (OptraContact, Ivoclar Vivadent) or separation ring (Composi-Tight Gold, Garrison Dental Solutions). Group 3: pre-contoured metal sectional matrix (Lite-Flex, Danville Materials) with separation ring. Groups 4 and 5: pre-contoured metal circumferential dead-soft matrix (Adapt SuperCap, KerrHawe) with or without separation ring. Group 6: flat metal circumferential matrix (OptraMatrix, Ivoclar Vivadent) in a Tofflemire-retainer with hand instrument (OptraContact). Proximal contact tightness was measured using the Tooth Pressure Meter (University of Technology, Delft). To determine the effect of experimental variables on the proximal contact tightness, a multiple linear regression model was constructed. RESULTS: Measurements in group 6 were not possible; therefore, this group was excluded. The use of medium- or high-viscosity instead of a low-viscosity composite resin resulted in statistically significantly tighter proximal contacts (p < 0.01). The use of a separation ring resulted in a large, statistically significant increase (p < 0.001) in contact tightness, while the use of a hand instrument resulted in a small, statistically significant increase of contact tightness (p = 0.017). No statistically significant differences were found when a dead-soft matrix or a sectional matrix was used instead of a Tofflemire (p = 0.159, p = 0.261, resp.). CONCLUSION: Use of a separation ring when restoring a Class II composite resin restoration has a greater influence on the obtained proximal contact tightness compared to the influence of the consistency of the composite resin.

Composite Resins↗
PubMedDate not supplied

Long-term deterioration of composite resin and amalgam restorations.

Previous long-term longitudinal studies of two different methods of placing an auto-cured conventional anterior composite resin, and of a low- and a high-copper amalgam alloy, had shown similar restoration survivals despite the different resin treatment methods used or the types of amalgam alloy placed. Therefore, the aim of the present study was to assess several clinical factors or characteristics of these restorations that were believed to affect the survival of the restorative materials. The 950 composite resin and the 1042 amalgam restorations examined were placed by many operators in numerous patients attending a dental hospital. The composite resin restorations were placed using unetched- and etched-enamel-bonding treatment methods, and the amalgam restorations were polished after insertion. Clinical ratings supplemented by color transparencies were used for the assessment of four factors for the resin, and four factors for the amalgam restoration. Significant deterioration differences were found for several of the clinical factors assessed for both the two different composite resin treatment methods, and for the two different amalgam alloys, which were not directly related to the restoration survivals.

Acid Etching, Dental↗
PubMed1990

[Effect of adhesive composite resin on pulp and capping of pulp with calcium hydroxide base (Dycal) in deciduous teeth of young dogs].

This study was designed to investigate the effect of adhesive composite resin (Clearfil SC Bond) on dental pulp and the effect of calcium hydroxide base (Dycal) on the protection of the pulp, using 66 deciduous teeth of young dogs. After forming a cavity (class 5) on the labial aspect in each tooth, the teeth were divided by the modes of plugging into 4 groups; stopping alone (Group S), stopping and capping with Dycal (Group D+S), capping with Dycal and resin (Group D+R) and capping with resin alone (Group R). After decalcification, the specimen was embedded in celloidin, sliced into thin sections and stained with hematoxylin and eosin for histopathological examination. Histological changes were examined at 3 days, 1 week, 2 weeks and 4 weeks. The following are the results obtained. 1. In Group S, slight histological changes were observed at 3 days and 1 week. However, the changes began to diminish after the 2nd week and disappeared in the 4th week. 2. In Group R, the severest histological changes persisted throughout the course of observation. The changes were not diminished even in the 4th week. Thus, the resin seemed to exert a strong and long-lasting stimulative effect against the pulp. 3. In Group D+S and D+R, the histological changes were more serve at 3 days and 1 week compared to those found in Group S, but these were diminished after the 2nd week. This seemed to suggest that the pulp was stimulated to a certain degree by Dycal but also, Dycal protected the pulp from stimulation of the resin. 4. Capping of the pulp seemed necessary in vital teeth with resin restoration.

Animals↗
PubMed1979

[Thermal expansion of restorative composite resins under the dry and wet conditions (author's transl)].

Linear coefficients of thermal expansion (beta) of twelve restorative composite resins, one Bis-GMA based resin and one self-curing acrylic resin were determined in the temperature range of 4 to 60 degrees C under the dry and the wet conditions on a thermomechanical analyzer. The results were as follows. 1) The thermal expansion curves obtained were nonlinear, and the transition appeared at about 40 degrees C. 2) beta reduced with the elapse of stored time and the number of times of measuring run. It appears that these phenomena were attributable to decrease of monomer remained in each case. 3) beta under the wet condition was larger than one under the dry condition, when specimens were stored for 20 days in each condition at 37 degrees C. Values of beta for composites ranged from 16.1 to 35.3 x 10(-6)/degrees C under the dry condition and from 18.1 to 55.4 x 10(-6)/degrees C under the wet condition. 4) beta of composites varied with filler content and kinds of filler and resin used. Value of beta reduced with increase of filler content, and was lower for Bis-GMA based composite resin than for MMA based composite resin.

Acrylic Resins↗
PubMed1994

Composite resin-amalgam compound restorations.

Extensive silver amalgam restorations in premolars and molars occasionally require sacrifice of healthy unsupported enamel walls or cusps. A posterior composite resin-amalgam compound technique has been proposed to conserve these structures. Microleakage was high at the enamel-amalgam interface, moderate at the composite resin-silver amalgam and dentin-composite resin interfaces, and minimal between the inner enamel and the composite resin. Light microscopy and scanning electron microscopy demonstrated that marginal adaptation of the silver amalgam to the composite resin of the cusps was acceptable and that penetration of the inner etched enamel to the composite resin was complete.

Bicuspid↗
PubMed1993

Study of pulpal response to an adhesive composite resin restoration using A NPG primer and a PMDM monomer (Mirage-Bond).

The purpose of this experiment was to investigate histo-pathologically and clinico-pathologically the pulpal reaction to a composite resin restoration system with a NPG primer and an adhesive bonding agent containing a carboxylate adhesive monomer, PMDM, using beagle dog and human teeth. The contact area between the composite resin with the primer and the monomer and the dentin cavity wall was observed through the SEM imaging. In the histo-pathological study, the average evaluation score of pathological results in group M (the composite resin restoration using the NPG primer and the bonding agent containing PMDM monomer "Mirage-Bond") was superior and almost the same as in group P as a contrast group (the composite resin restoration using a bonding agent "Clearfil Photo Bond" after enamel and dentin wall etching with 40% phosphoric acid). The dispersion of pathological results by score in group M was much narrower than in group P. Microorganism growth in group M was less than that of group P. Gap spaces caused by coming off in the region of contact area between the filled resin and the dentin cavity wall were observed through the SEM imaging. The number of cases coming off in group M were fewer than in group P. Gap spaces in group M were narrower in width than in group P. In the SEM imaging, microorganisms were observed in most cases with gap areas. In the clinico-pathological study on restoration with "Mirage-Bond", unpleasant sings symptoms had not occurred except in a few cases. The pathological result by score was comparatively superior. The pathological results of human teeth were similar to the pathological results of dog teeth. The pulpal irritation due to this composite resin restoration system with the NPG primer and the PMDM monomer containing adhesive bonding agents was generally minor, and the system was considered to be safe and useful even though the contraction gap spaces were found in some cases.

Adolescent↗
PubMed1993

The influence of lining techniques on the marginal seal of Class II composite resin restorations.

Various sealing techniques using a light-curing dental adhesive (Scotchbond 2) and bulk application of a light-curing resin-bonded ceramic were examined in 203 Class II cavities. Different pretreatment procedures and lining materials were used, and in one series resin impregnation of the contraction gap was included. The presence of gaps or leakage was disclosed either by a dye or a fluorescent resin penetration technique. In many restorations, Scotchbond 2 and a light-curing glass-ionomer lining did not prevent gap formation at the cervical wall. The gap usually occurred between the liner and the dentin, with dye penetration into the dentin. Three liners, one containing polytrifluorethylene sodium fluoride and calcium fluoride, one containing polyamide resin, and one containing calcium hydroxide, did not prevent dye penetration to the dentin at all; good dentinal protection was frequently observed, however, in cavities treated with a hydrophilic shellac film prior to placement of a polystyrene liner. The best results were observed when dentinal treatment with this lining system was followed by resin impregnation of the contraction gap after the composite resin had set.

Composite Resins↗
PubMed1995

Resin adhesion to the primary enamel: influence of light-irradiation times.

The purpose of this study was to investigate the influence of the light-irradiation times to the bonding agent and the composite resin on resin adhesion to the primary enamel. One hundred bovine mandibular ground primary incisors were used. Materials used in this study were 40% phosphoric acid gel, Photo Bond and Photo Clearfil A (Kuraray Co., Kurashiki, Japan). The etching time was 30 seconds. The light-irradiation times for the bonding agent were 10, 20 and 30 seconds and the light-irradiation times for the composite resin were 20, 40 and 60 seconds. Specimens were divided into the non-thermal cycled groups and the thermal cycled groups. Shear bond strengths were tested. After the shear bond strength test. the test surfaces of the enamel and the resin specimens were observed using the SEM. The optimum light-irradiation time on the bonding agent was 10 seconds. Both in the non-thermal cycled group and the thermal cycled group, the light irradiation time on the composite resin which showed the significantly higher bond strength was 40 seconds. Higher bond strength was not always obtained with the longer light-irradiation time on the bonding agent and the composite resin.

Acid Etching, Dental↗
PubMed1995

The composition and ultrastructure of resin tags in etched dentin.

PURPOSE: To examine in vitro the composition of resin tags in etched dentin by SEM and vital staining using Alcian Blue dye. MATERIALS AND METHODS: Bovine and human teeth were used. The dentin surface was exposed using water-irrigated #600 grit SiC paper and etched with varying dilutions of aquaeous solutions of phosphoric and maleic acid. Groups of 10 teeth per acid concentration were embedded in PMMA and Scotchbond Multi-Purpose (SMP) and cylinders of Z100 resin composite were bonded to their surfaces. These teeth were shear tested to failure and the failed surfaces subjected to SEM. Groups of three teeth per acid concentration had SMP and cylinders of Z100 bonded to their surfaces. These teeth were decalcified in concentrated HCL acid. The resultant cylinders and their attached resin tags were either subjected to SEM or stained with Alcian Blue dye. The latter specimens were embedded and prepared for light-microscopic examination. A further three human and three bovine teeth per acid concentration were etched and then prepared for SEM examination. All teeth for SEM were critical point dried. RESULTS: Resin tags were shown to consist of both resin and the glycosaminoglycans (GAG) sheath lining of the dentin tubule. As a result of the SEM observations, three mechanisms are suggested for the formation of resin tags, two of which will probably be found in vivo.

Acid Etching, Dental↗
PubMedDate not supplied

In vitro caries inhibition effects by conventional and resin-modified glass-ionomer restorations.

The ability of a material to inhibit recurrent caries formation is an important clinical therapeutic property. The objectives of this study were to develop an initial anticariogenicity profile (from fluoride release, to fluoride uptake, to resistance to an artificial caries challenge), testing the ability of conventional versus resin-modified glass-ionomer restorations to resist decay, and to study the effect of using intermediary dentin bonding agent components on the development of surface and wall carious lesions adjacent to a resin-modified glass-ionomer restoration. Cumulative fluoride release was measured from the immersion of disk-shaped specimens into deionized distilled water for 24 hours, 1, 2, 4, and 10 weeks. For the fluoride uptake and artificial caries test, standardized restorations were placed along the cementoenamel junction of extracted human molars. Secondary ion mass spectroscopy was used to determine the depth of fluoride uptake into the adjacent axial dentin from the restoration after 1 and 10 weeks. For the artificial caries test, the teeth were immersed into an acidified gelatin gel, pH 4.0, for 10 weeks. The development of recurrent decay was assessed using polarizing light microscopy. Statistical analyses were conducted using ANOVA and Fishers' LSD test (P < or = 0.05). There was generally greater fluoride release and uptake from the conventional glass ionomers, equivalent or less from the resin-modified glass ionomers, and none from the resin composite restorations. The use of an acid conditioner and primer from a dentin bonding system significantly increased the depth of fluoride uptake at 1 week. The additional use of an intermediary adhesive resin layer, however, significantly decreased the depth of fluoride uptake. The maximum depth of fluoride uptake into dentin was 300 microns at 10 weeks. Both conventional and resin-modified glass-ionomer restorations imparted resistance to dentin against the development of recurrent wall carious lesions in vitro. This was attributed to material fluoride release and uptake.

Cariostatic Agents↗
PubMed1997

Reinforcement of acrylic resins for provisional fixed restorations. Part I: Mechanical properties.

Acrylic resins are commonly used in many dental applications; especially in the fabrication of provisional fixed partial dentures. Among noticed technical drawbacks associated with this material are unsatisfactory mechanical properties. Moreover, if acrylic resins are exposed to moist environment, water sorption results in further mechanical deterioration. In order to improve the mechanical properties, aluminum, magnesium, and zirconium oxide powders and pulverized E-glass particles were separately admixed with pre-polymerized acrylic resin beads prior to mixing with monomer liquid. Particle loading ratios were 1, 2 and 3 vol.% with respect to pre-polymerized beads. Poly(methyl methacrylate), poly(ethyl methacrylate) and poly(isobutyl methacrylate) were used as resin matrices. Furthermore, a metal primer agent was employed in order to form a strong interphase between admixed particles and polymer matrix phase. Samples were subjected to three-point transverse bending tests at a crosshead speed of 10 mm/min. It was concluded that (1) addition of particles generally increases the water sorbed by the composite resins systems, (2) however, two vol.% admixtures in a PMMA resin matrix showed significant improvements in the mechanical properties (p < 0.05), (3) among the oxide particles, zirconia exhibited the greatest improvements in modulus of elasticity, transverse strength, toughness and hardness, and (4) mechanical properties (transverse strength, 0.2% offset yield strength and modulus of elasticity) were linearly correlated to hardness numbers.

Acrylic Resins↗
PubMed2001

Fluoride release from glass-ionomer cements, compomers and resin composites.

The short and long-term fluoride release of 16 products (seven conventional glass-ionomers, five light-activated glass-ionomers, two polyacid-modified resin composites and two resin composites) commercialized as fluoride-releasing materials were measured. A potential link between the material type and its level of fluoride release was researched. The fluoride release was evaluated after different time intervals. Initial fluoride release from all materials was highest during the first 24 h and decreased sharply over the first week. Some groups of materials appeared to be significantly different after, respectively, 7 and 91 days. However, it was impossible to correlate the fluoride release of the materials by their type (conventional or resin-modified glass-ionomers, polyacid-modified resin composite and resin composite) except if we compared the products from the same manufacturer. The link between fluoride release and an acid-base reaction seems to be confirmed. The glass-ionomer composition (glass particles and polyacid's type, powder/liquid ratio) should have more influence on fluoride release than material type.

Acids↗