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PubMed2026

Clinical performance evaluation of single-shade versus multi-shade composite resins in non-carious cervical lesions: a 36-month randomized clinical trial.

BACKGROUND: Composite resins are widely used as the material of choice for definitive restorations due to their ability to integrate functional and aesthetic aspects in dental rehabilitation. Recently, one-shade composite resins have been introduced to simplify the clinical workflow. OBJECTIVES: This study aimed to compare the clinical performance of a "chameleon effect" composite resin with that of a multi-shade composite resin in non-carious cervical lesions after 36 months of follow-up. METHODS: This study was a randomized, controlled, double-blind clinical trial with an equivalence design using a split-mouth approach. The sample consisted of 60 patients presenting at least two non-carious cervical lesions, totaling 120 restorations. Restorations were performed using two materials from the same commercial brand: Vittra Unique (one-shade group) and Vittra APS (multi-shade group). The clinical performance of the restorations was longitudinally evaluated according to the FDI criteria. Survival analysis was performed using Kaplan-Meier curves and the log-rank test, while other clinical parameters were compared using the chi-square test (α = 0.05). RESULTS: At baseline, no statistically significant differences were observed between the groups regarding the evaluated biological, functional, and aesthetic parameters (p > 0.05). Both materials demonstrated clinically acceptable performance according to the FDI criteria, with no significant differences between them. CONCLUSIONS: After 36 months, no significant differences were observed between the one-shade and the multi-shade composite resins in the restoration of non-carious cervical lesions. CLINICAL SIGNIFICANCE: This 36-month randomized clinical trial demonstrates that single-shade composite resins achieve structural durability and aesthetic integration equivalent to traditional multi-shade layering when restoring non-carious cervical lesions. This evidence validates a simplified, single-shade restorative workflow, significantly reducing chairside time and operator-dependent variables without compromising the clinical longevity.

Humans↗
PubMed2005

Effect of surface sealant and staining on the fluorescence of resin composites.

STATEMENT OF PROBLEM: Natural teeth and several commercial resin composites emit a strong blue fluorescence when exposed to ultraviolet (UV) light, which makes teeth whiter and brighter in daylight. Surface sealant and staining may change the fluorescence of resin composites. PURPOSE: The purpose of this study was to determine the effect of surface sealant application and staining/stain removal on the fluorescence of resin composites. MATERIAL AND METHODS: Spectral reflectance and color of 4 resin composites (Filtek Supreme, Gradia Direct, Simile, and Vit-l-escence) were measured with/without application of a surface sealant (BisCover) at baseline and after staining/stain removal (n = 5). A UV filter was used to exclude or include the UV component of illumination. Fluorescence spectra were calculated by subtracting the spectral reflectance values of the UV component excluded condition from those of UV included condition. For staining, specimens were sequentially immersed in mucin, chlorhexidine, and a tea solution. Stain removal was performed by ultrasonic cleaning and PBS (phosphate buffered saline) immersion. Color difference (DeltaE 00) by the UV component was calculated based on CIEDE2000 color system. Delta E 00 due to staining and stain removal were also calculated. Changes in color and fluorescence by the staining and stain removal were analyzed by 2-way analysis of variance (alpha=.05). RESULTS: Sealant application decreased fluorescence of resin composites. After staining, fluorescence was not detected except for 1 composite. After stain removal, a decrease in fluorescence from the baseline was observed, and 2 composites showed significant decrease ( P <.05). CONCLUSION: Fluorescence of resin composites decreased or disappeared after surface sealant application and/or staining procedure.

Acrylates↗
PubMed2006

Long-term effects of storage and thermal cycling on the marginal adaptation of provisional resin crowns: a pilot study.

STATEMENT OF PROBLEM: Provisional resin crowns may be used for an extended period while complex treatments are completed. The crowns function intraorally; therefore, moisture absorption and thermal cycling may affect the physical properties of acrylic resin, causing a change in marginal gap size. PURPOSE: The purpose of this pilot study was to examine the effect of long-term water absorption and thermal cycling on marginal gap size of polymethyl methacrylate copolymer and bis-acrylic composite resin crowns. MATERIAL AND METHODS: Specimens (n = 10) were fabricated from 2 acrylic resins: a polymethyl methacrylate (Alike) and a bis-acrylic composite resin (Provitec). Specimens were first fabricated on a metal master die. Custom die stems were fabricated for each specimen from a low-fusing alloy (Cerroblend) to eliminate the factor of polymerization shrinkage. Specimens were then fitted to assure a standardized, pre-experimental marginal gap range of < or = 25 microm. Specimens were stored in a humidor at 37 degrees C and 97% relative humidity for 1 year and subsequently thermal cycled (5 degrees C to 60 degrees C, 6-second dwell time, for 8000 cycles). Measurements in micrometers of the marginal gap were recorded using a microscope equipped with a digital video camera and image analysis software before and after treatment. A 2-way analysis of variance with a split design was performed for factors of materials and treatment (alpha = .05). RESULTS: For the factor of material, there was no significant difference; however, there was a significant difference between treatments, with a significantly greater increase in marginal gap size after thermal cycling (P < .002). CONCLUSION: Provisional crowns made from either a bis-acrylic resin composite or a polymethyl methacrylate copolymer demonstrated loss of marginal adaptation during a simulated long-term period of service.

Acrylic Resins↗
PubMed1980

Peptide separations on substituted polystyrene resins. Effect of cross-linkage.

The effect of copolymer cross-linkage on the resolution of soluble tryptic peptides of human globin (alpha- and beta-chains) separated in columns containing substituted polystyrene resin classified to 11 +/- 1 micrometer has been examined. With both the cation and anion exchange resins, polymers of lower cross-linkage provided better resolution; inferior resolution was obtained with 12% cross-linked resins. It was also observed that microparticle anion-exchange resins could be used in columns maintained at 55 degrees instead of 35 degrees as used traditionally. Resolution and yield with 20 x 1 cm resin beds were generally as good as or superior to much longer columns of crushed bead resin of the same chemical structure.

Anion Exchange Resins↗
PubMed1991

Shear bond strength of two resin adhesives for acid-etched metal prostheses.

This study compared the shear bond strength of Panavia EX and Comspan Opaque adhesive resins with electrolytically etched or sandblasted Rexillium III or Litecast B metals bonded to extracted teeth. An analysis of variance revealed that there is no difference in bonding strength among etched or sandblasted Rexillium III metal with either Panavia EX or Comspan Opaque resins. With Litecast B metal, sandblasting produced a greater bond strength than etching with Panavia Ex resin (38.19 MPa sandblasted; 30.53 MPa etched). Conversely, Comspan Opaque resin had a value of 30.10 MPa etched and 15.40 MPa sandblasted. The etched Rexillium III and Panavia EX resins recorded a greater bond strength (38.38 MPa) than Comspan Opaque resin (27.83 MPa) or sandblasted Rexillium III metal (Rexillium III 34.74 MPa; Comspan Opaque 20.39 MPa) and Litecast B metal (Panavia EX 38.19 MPa; Comspan Opaque 15.40 MPa). Eighty percent of the failures occurred at the cement-metal interface with both cements.

Acid Etching, Dental↗
PubMed1996

Tensile bond strength of enamel-resin-metal joints.

This study observed the effects of the alloy type, resin type, and simulated occlusal loading on enamel-resin-metal tensile bond strength. Three different dental alloy samples were sandblasted with 50 microns of desiccant alumina and then bonded to the buccal and lingual halves of extracted human molars with four different dental resins. Specimens were divided into two groups, which included different halves of tooth samples. For one group tensile strength was tested after 19.8 N per 60,000 loading cycles. For the other group tensile testing was performed without cyclic loading. The results revealed that enamel-resin-metal bond strength was not affected by alloy type. However, a close relationship between the resin type and the bond strength was found. It was demonstrated that Panavia Ex and Concise resins produced greater bond strengths than did ABC and MBA cements. Also, a significant decrease in tensile bond strength values occurred after cyclic loading.

Acrylic Resins↗
PubMed1997

Bond strengths of resin-to-metal bonding systems.

STATEMENT OF PROBLEM: Resinous materials for the veneers of fixed prostheses commonly require mechanical retention on metal substructures because there is no chemical adhesion. However, mechanical retention does not restrict creation of a marginal gap at the resin-metal interface, which can cause discoloration or detachment of resinous material. The development of a chemical resin-to-metal bonding could resolve this problem and also reduce the need for mechanical retention (pearls, wires) on metal frameworks. PURPOSE: This study evaluated six current methods with the use of various storage conditions to predict clinical efficacy. MATERIAL AND METHODS: Six resin-to-metal bonding systems were tested: Silicoater, Silicoater MD, Rocatec, OVS, Sebond, and Spectra-Link. All specimens were examined in bending tests after 24 hours of dry storage (category A), after 24 hours of water storage and thermocycling (category B), and after 2 months of water storage and thermocycling (category C). Tensional tests were completed for all bonding systems after dry storage, and microscopic examination (optical and SEM) was performed for all specimens. RESULTS AND CONCLUSIONS: This study indicated that certain systems can provide stable bonding of resin to metal substructures despite prolonged wet storage and intensive thermocycling. These systems can also be used clinically without retentive configurations on metal frameworks, resulting in better esthetics. Some bonding systems revealed progressive weakening of bond strengths, so research is needed to verify their clinical efficacy.

Dental Alloys↗
PubMed2001

The influence of resin composite and bonded amalgam restorations on dentine permeability in Class II cavities in vitro.

OBJECTIVES: This study was conducted to measure and compare dentine permeability reduction in Class II preparations, after restoration with resin composite or bonded amalgam, using either a multi-step or one-bottle dental adhesive system. METHODS: An in vitro fluid transport model was used to measure initial dentine permeability in Class II cavities with an intact smear layer in crown segments from extracted human premolars. One week and 3 months after restoration with resin composite or bonded amalgam, using either multi-step or one-bottle dental adhesive system, the measurements were repeated and the reduction in permeability was calculated as a percentage of the initial values. The data were analyzed statistically using a one-way ANOVA and Least Significant Difference tests. RESULTS: After 1 week the resin composite with one-bottle dental adhesive system provided the highest reduction in dentine permeability, whereas after 3 months the bonded amalgam caused the highest reduction. At both time intervals the resin composite with multi-step adhesive system provided the lowest reduction. (P=0.036 at 1 week, P=0.016 at 3 months). After 3-months storage in water a significant increase in dentine permeability reduction was found in the bonded amalgam group only (P=0.017). The reduction in dentine permeability provided by resin composite with one-bottle dental adhesive system and bonded amalgam in Class II cavities was similar at both time intervals. (P=0.182 at 1 week, P=0.750 at 3 months). SIGNIFICANCE: The results of this study indicated that on the basis of reducing dentine permeability in vitro, resin composite restorations with the investigated one-bottle adhesive system was superior to its multi-step equivalent and bonded amalgam can also be preferred in Class II restorations.

Adolescent↗
PubMed2003

Mechanical property characterization of resin cement after aqueous aging with and without cyclic loading.

OBJECTIVE: The purpose of this study was to determine changes in flexural properties of resin cement under cyclic loading and aqueous aging. METHODS: Panavia F flexural modulus and strength were measured by static loading to failure after 48-h, 31-d, and 60-d aqueous aging at 37 degrees C with and without cyclic loading at clinical stress levels. Six specimens were used for each experimental condition. Scanning electron microscopy (SEM) was also used to characterize the morphology of the fractured surfaces to potentially identify resin cement components particularly susceptible to degradation under simulated clinical function. RESULTS: A two-factor ANOVA (p< or =0.05) and Least Significant Difference post hoc test indicated that cyclic loading produced a significant increase in the flexural modulus with no significant effect on the flexural strength. In contrast, aqueous aging time produced a significant decrease in flexural strength with no effect on the flexural modulus. The SEM fracture analysis indicated that resin matrix fracture occurred in static-aqueous specimens; while in the aqueous-cycled specimens, resin matrix fracture occurred in addition to an increasing proportion of filler/resin interface fracture as a result of both increased aqueous aging and increased flexural cycles. SIGNIFICANCE: Evidence suggests that after aqueous aging with cyclic loading to simulate resin cement clinical function, initial degradation may be related to breakdown of the filler/resin interface bond. Such breakdown is potentially reflective of slow crack propagation that may contribute to in vivo resin cement cohesive failure.

Analysis of Variance↗
PubMed2002

The bond strength of light-curing composite resin to finally polymerized and aged glass fiber-reinforced composite substrate.

OBJECTIVE: This study examines the shear bond strength of visible light-curing composite resin (VCR) to aged glass fiber-reinforced composite (FRC) substrate with multi-phase polymer matrix. METHODS: Linear polymethyl methacrylate and dimethacrylate monomer preimpregnated unidirectional glass fiber reinforcement was used as an adhesion substrate for low-viscosity diacrylate veneering composite resin and restorative composite resin. A total of 60 test specimens were divided into three groups according to the brand and the use of an intermediate monomer resin (IMR). The used IMRs were either BisGMA-HEMA-resin, BisGMA-TEGDMA resin or the controls were left without the IMR treatment. Dry- and water-stored FRC-substrates were used for adhering the VCR with or without the IMR. The shear bond strength of the VCR to the substrate was measured for dry and thermocycled specimens and the results were analyzed with multi-variate ANOVA. RESULTS: The highest mean shear bond strength (23.9 +/- 4.8 MPa) was achieved with FRC/BisGMA-HEMA/VCR combination when the FRC substrate was water stored and the test specimen was thermocycled. FRC/BisGMA-TEGDMA/VCR combination resulted in 15.7 +/- 6.0 MPa with the water-stored FRC substrate and after thermocycling of the test specimens. The lowest shear bond strength (1.0 +/- 0.5 MPa) was obtained with FRC/VCR combination with water-stored substrate and after thermocycling of the test specimens. Significant differences were found between the mean values of three groups according to the use of IMR (p<0.001). The storage conditions of the FRC substrate were related to brand of the IMR or the composite (p<0.001). High mean values of the shear bond strength after thermocycling fatigue were related to the type of IMR (p<0.001). SIGNIFICANCE: The results suggest that the IMRs used in this study greatly influence the mean shear bond strength values when the test specimens are thermocycled.

Analysis of Variance↗
PubMed1997

A laboratory evaluation of the construction of resin-bonded cast restorations.

OBJECTIVE: To compare the effect of two construction techniques and two pattern materials on the fit of resin-bonded cast restorations. DESIGN: In-vitro study carried out by one operator. SETTING: Postgraduate university hospital. SUBJECTS AND METHODS: 65 nickel-chrome castings were constructed using refractory die and lift-off techniques with wax and acrylic resin pattern material. They were cemented onto master silver dies, embedded in self-curing acrylic resin and sectioned along their long axes. Interfacial distance between the master silver die and casting was measured. RESULTS: A significant different between the range of figures in each group (Mann-Whitney Test, P < 0.01) was found. Construction techniques can be ranked in order of fit of castings: 1. Refractory die, wax patterns: 42.6 microns (SD 12.03). 2. Refractory die, acrylic resin patterns: 53.7 microns (SD.16.06).3. Conventional technique, acrylic resin patterns: 85.5 microns (SD 31.62). 4. Lift-off technique, wax patterns: 139 microns (SD 53.15).5. Lift-off technique, acrylic patterns: 172.8 microns (SD 74.04). CONCLUSIONS: Castings constructed using refractory die technique and subsequently cemented resulted in a more accurate and less variable fit than those produced with the lift-off technique. Wax patterns lead to more accurate castings than acrylic resin and locating indentations may interfere with the cementation of castings when lift-off techniques are used.

Acrylic Resins↗
PubMed1999

Antibacterial activity of resin composites with silver-containing materials.

Resin composites with antibacterial activity may be useful to decrease the frequency of secondary caries around restorations. The purposes of this study were to investigate the antibacterial activity of light-activated resin composites incorporating one of three silver-containing materials and to evaluate their long-term inhibitory effect against Streptococcus mutans The three types of silver-containing materials, Novaron (N), Amenitop (AM), and AIS, were incorporated into TEGDMA-UDMA-based light-activated resin composites, and the antibacterial activities, mechanical properties and release of silver ions were examined. Minimum inhibitory concentrations in suspensions of N, AM, and AIS against S. mutans were 1.1, 1.2, and 23.0 mg/ml, respectively. Resin composites incorporating 5 wt% of Novaron (N-5) and 7 wt% of Amenitop (AM-7) inhibited the growth of S. mutans after immersion in water for 3 months, whereas the resin composite incorporating 10 wt% of AIS did not. No significant difference in either compressive or flexural strength was observed between the control and N-5 composites after 1 d and 3 months storage in water. However, for AM-5 composite, there was a significant difference in both strength parameters between the two immersion periods. There was no or extremely little release of silver ions from the N-5 and AM-5 composites after 1 d or 3 months immersion in water. These results indicated that a light-activated resin composite incorporating silver-containing materials such as Novaron may be clinically useful due to its long-term inhibitory effect against S. mutans and favorable mechanical properties.

Aluminum Oxide↗
PubMed1997

Water sorption and solubility of resin-modified polyalkenoate cements.

The purpose of this study was to compare the water sorption and solubility of several resin-modified polyalkenoate cements. The materials evaluated included Variglass used as a restoration, base on liner; Fuji II LC, Fuji Liner; Vitrebond; Vitremer and Photac-Bond. Z100, a composite resin, was used as control. All specimens were manipulated according to the manufacturers' instructions and then subjected to water sorption and solubility tests based on the ISO 4049 requirements. Data were subjected to one-way ANOVA and Duncan's test at a 0.05 significance level. Results show that the composite resin control had significantly less water sorption than any of the resin-modified polyalkenoate cements evaluated. The degree of water sorption was product dependent and appeared to be influenced by the resin (HEMA) content. There was no apparent correlation between water sorption and solubility. Some of the resin-modified polyalkenoate cements retained water in their set structure and hence solubility could not be assessed.

Absorption↗
PubMed2001

Effect of three adhesive primers for a noble metal on the shear bond strengths of three resin cements.

The purpose of this study was to evaluate the durability and shear bond strengths of the different combinations of three adhesive primers and three resin cements to a silver-palladium-copper-gold (Ag-Pd-Cu-Au) alloy. The adhesive primers Alloy Primer (AP), Metal PrimerII (MPII) and Metaltite (MT), and the resin cements BistiteII (BRII), Panavia Fluoro Cement (PFC) and Super-Bond C&B (SB) were used. Two sizes of casting alloy disks were either non-primed or primed and cemented with each of the three resin cements. The specimens were stored in a 37 degrees C water bath for 24 h and then immersed alternately in 4 and 60 degrees C water baths for 1 min each for up to 100,000 thermal cycles. Shear mode testing at a crosshead speed of 0.5 mm/min was then performed. The application of MPII or MT was effective for improving the shear bond strength between each of the three resin cements and the Ag-Pd-Cu-Au alloy compared with non-primed specimens. However, when primed with MPII or MT and cemented with SB, the bond strength at 100,000 thermal cycles was significantly lower than that at thermal cycle 0. When primed with AP, the specimens cemented with BRII or PFC showed lower bond strength than non-primed specimens and failed at the metal-resin cement interface at 100,000 thermal cycles. On the other hand, AP was effective in enhancing the shear bond strength of SB to the Ag-Pd-Cu-Au alloy. The five combined uses of an adhesive metal primer and resin cement (combinations of MPII or MT and BRII or PFC and AP and SB) are applicable to the cementation of prosthodontic restorations without complicated surface modification of the noble alloy.

Adhesives↗
PubMed2003

Resin-ceramic bonding: a review of the literature.

Current ceramic materials offer preferred optical properties for highly esthetic restorations. The inherent brittleness of some ceramic materials, specific treatment modalities, and certain clinical situations require resin bonding of the completed ceramic restoration to the supporting tooth structures for long-term clinical success. This article presents a literature review on the resin bond to dental ceramics. A PubMed database search was conducted for in vitro studies pertaining to the resin bond to ceramic materials. The search was limited to peer-reviewed articles published in English between 1966 and 2001. Although the resin bond to silica-based ceramics is well researched and documented, few in vitro studies on the resin bond to high-strength ceramic materials were identified. Available data suggest that resin bonding to these materials is less predictable and requires substantially different bonding methods than to silica-based ceramics. Further in vitro studies, as well as controlled clinical trials, are needed.

Aluminum Oxide↗
PubMed2002

Long-term fluoride release from a glass ionomer cement, a compomer, and from experimental resin composites.

The aqueous phase of glass ionomer cements enables fluoride ions to diffuse and to be released from the material. The matrix of resin composites is much less hydrophilic, and fluoride incorporated in the material is only released in small amounts. It was the purpose of the present work to study the influence of resin matrix formulation on the fluoride release from experimental, fluoride-containing resin composites. The resin composites were based on methacrylate monomers and the adduct of maleic anhydride and HEMA (2-hydroxyethyl methacrylate). The resin composites contained 1 w% or 5 w% of AlF3*3H2O. A glass ionomer cement and a compomer were used as controls. Five disks of each material were stored in distilled water at room temperature. By means of a fluoride sensitive electrode, the fluoride release from disk-shaped specimens was determined periodically over 3 years. The glass ionomer cement released the most fluoride (1.54 +/- 4 microg/cm2 after 1 year and 248 +/- 7 microg/cm2 after 3 years). The compomer released relatively little fluoride during the 1st year (30 +/- 1 microg/cm2) but after this time the rate of fluoride release became equal to that of the glass ionomer cement, resulting in a release of 122 +/- 8 microg/cm2 after 3 years. Regarding the resin composites, the fluoride release increased with the hydrophilicity and the acid character of the polymer matrix. The release, however, was significantly lower than that from the glass ionomer cement and the compomer and ranged from 1.2 +/- 0.07 to 42 +/- 3.9 microg/cm2 at 1 year and from 2.3 +/- 0.16 to 79 +/- 6 microg/cm2 at 3 years.

Aluminum Compounds↗
PubMed2006

Biological effects of flowable resin composite on erythrocytes and lymphocytes using an in vitro model.

AIM: The purpose of the study was to evaluate the biological effects of a flowable resin composite on erythrocytes and rat spleen lymphocytes (RSL) using an in vitro model. METHODOLOGY: Rat spleen lymphocytes were placed into microcentrifuge tubes as a pulp model. An artificial pulp exposure was made through the top of the microcentrifuge tube with a 16G needle. The exposure site was filled with a flowable resin composite and photo-polymerized, and the other specimens were not polymerized. The survival rates were determined by a haemocytometer. Red blood cell (RBC) suspension (0.5%) was reacted with the flowable resin composite. The haemolytic activity was evaluated at room temperature (20 degrees C) using a supernatant of each sample by measuring 545 nm of absorbency with a spectrophotometer. To evaluate the effect of flowable resin composite on RBCs, supernatant and precipitated samples were analysed by sodium dodecyl sulphate-polyacrylamide gel (SDS-PAGE). RESULTS: The cell survival rate of the polymerized group was significantly lower compared with that of the nonpolymerized group at the same areas (P < 0.05). The values of haemolysis (absorbency) were 2.16 for the polymerized group, 2.14 for the nonpolymerized group, and 2.18 for the control group (saline). There were no significant differences among them (P > 0.05). The protein component in the supernatant and precipitate exhibited the same reaction with flowable resin composite regardless of the completion of the polymerization, resulting in no change of protein band mobility on SDS-PAGE. CONCLUSIONS: The degree of haemolysis was not influenced by the completion of polymerization. The flowable resin composite tested provoked an adverse effect on lymphocytes when it was not polymerized and the degree of haemolysis was not affected by the status of the polymerization.

Animals↗
PubMed2007

Effect of placement of calcium sulphate when used for the repair of furcation perforations on the seal produced by a resin-based material.

AIM: To evaluate the sealing ability of calcium sulphate when used under composite resin for the repair of furcation perforations having different diameters. METHODOLOGY: Perforations of different diameter were created in the floors of pulp chambers in 60 extracted human molar teeth with either a number 3 (1 mm diameter) or 5 (1.5 mm diameter) round bur. The specimens of each group were divided into four sub-groups which were repaired with composite resin either alone or in combination with calcium sulphate that created an artificial floor (15 teeth group(-1)). Eight teeth without furcation perforations served as negative controls. In the leakage detection device, 1 mol L(-1) glucose solution was forced under a pressure of 1.5 KPa from the crown towards the pulp chamber floor. The concentration of leaked glucose was measured at 1, 2, 4, 7, 10, 15 and 20 days using a glucose oxidase method and the data evaluated using the rank sum test. RESULTS: The specimens with larger perforations repaired with composite resin alone had significantly more leakage (P < 0.05). Using calcium sulphate as an artificial floor significantly decreased leakage of smaller perforations (P < 0.05). In groups repaired with calcium sulphate under composite resin, leakage in smaller perforations was markedly lower than that in larger ones (P < 0.05). No significant difference was found between the specimens with 1 or 1.5 mm perforations repaired with resin alone (P > 0.05). CONCLUSIONS: Calcium sulphate significantly improved the sealing ability of 1 mm perforations repaired with composite resin but not for 1.5 mm perforations.

Calcium Sulfate↗