Macro- and microtopographical examination and quantification of CAD-CAM composite resin 2- and 3-body wear

Impact of varnishing, coating, and polishing on the chemical and mechanical properties of a 3D printed resin and two veneering composite resins

STATEMENT OF PROBLEM

Three-dimensional (3D) printing enables the fast fabrication of definitive fixed dental prostheses (FDPs). However, data on the effects of surface treatments on their chemical and mechanical properties are lacking.

PURPOSE

The purpose of this in vitro study was to examine the influence of different surface treatments on a 3D printed resin in comparison with 2 veneering composite resins.

MATERIAL AND METHODS

A total of 288 specimens were manufactured from a 3D printed resin (VarseoSmile Crownplus) or veneering composite resins (GRADIA PLUS; VITA VM LC flow). Surfaces underwent varnishing, coating, polishing or remain untreated. Conversion rate (DC), surface roughness (SR), Martens parameter, flexural strength (FS), and 3-body wear (3BW) were determined (n=12). Statistical analysis was performed using Mann-Whitney-U, Kruskal-Wallis, and Spearman correlation tests (α=.05).

RESULTS

After polishing, the 3D printed resin showed higher DC, SR, and 3BW but lower Martens parameters compared with veneering composite resins (P<.007). After goat hair brushing, the 3D printed resin showed lower FS than VITA-VCR (P=.043). For the 3D printed resin, goat hair brushing or GC-Varnish reduced SR, while VITA-Varnish showed the lowest 3BW (P<.045). For both veneering composite resins, goat hair brushing led to low SR and 3BW and high EIT and FS (P<.043). Silicone polishing led to low EIT of the 3D printed resin and low EIT and FS of GC-VCR (P<.009). Coating resulted in a lower EIT than the untreated surface and higher 3BW than GC-Varnish (P<.030).

CONCLUSIONS

The 3D printed resin showed higher DC, SR, 3BW and lower HM, EIT, and FS values than the veneering composite resins. Polishing with a goat hair brush can be recommended for all tested materials. For the 3D printed resin, varnishing presents a promising alternative with regard to SR and 3BW. Silicone polishing and coating cannot be recommended.

Surface roughness, wear, and abrasiveness of printed and milled occlusal veneers after thermomechanical aging

STATEMENT OF PROBLEM

Occlusal veneers are a conservative method of reestablishing vertical dimensions of occlusion (VDO) for worn teeth. A restorative material used for occlusal veneers should have a smooth surface, adequate wear resistance, and low abrasiveness to the antagonists, as total wear of occlusal veneers and their antagonists determines the stability of the reestablished VDO. Studies on roughness, wear, and abrasiveness of occlusal veneers are scarce.

PURPOSE

The purpose of this in vitro study was to assess the surface roughness, wear, and abrasiveness of printed and milled occlusal veneers after thermomechanical aging against natural cusps and restorative materials.

MATERIAL AND METHODS

Forty-eight extracted mandibular first molars were prepared for occlusal veneers and scanned with an intraoral scanner. The scans were exported to a computer-aided design program to design the occlusal veneers in 3 groups (n=16) according to the restorative material: group IP: milled lithium disilicate; group EN: milled hybrid ceramic (Vita Enamic), group VA: printed hybrid ceramic (Varseosmile Crown plus). The occlusal veneers in each group were bonded to their corresponding abutments and subjected to 250 000 mechanical cycles and a simultaneous 1000 thermal cycles in a mastication simulator. During thermomechanical aging, half of the specimens of each study group (n=8) were opposed by natural cusps (antagonist C) and the other half by antagonist cusps fabricated from the same restorative material as the occlusal veneers (antagonist R). The wear of the occlusal veneers and their antagonists was assessed with a 3-dimensional processing software program. The surface roughness of the veneers was assessed with a contact profilometer. The results were statistically analyzed with a 2-way ANOVA followed by the post hoc Tukey HSD test (α=.05).

RESULTS

The 2-way ANOVA indicated a significant effect for the material and the antagonist on surface roughness, wear, and abrasiveness (P<.05). When opposed by antagonist C, VA showed significantly higher surface roughness than IP and EN (P<.001). VA had significantly higher surface wear followed by EN and IP (P<.001). IP caused significantly higher wear to antagonist C than EN and VA (P<.001). In addition, IP had significantly higher total wear (combined wear of veneers and their antagonists) followed by VA and EN (P<.001). When opposed by antagonist R, no significant difference was found among the 3 materials for surface roughness (P=.08), material wear (P=.12), opposing wear (P=.11), or total wear (P=.11).

CONCLUSIONS

Both material and antagonist had a significant effect on surface roughness and occlusal stability when occlusal veneers were fabricated to restore VDO. VA had significantly more surface roughness and wear than EN and IP when opposed by natural cusps. IP abraded natural cusps significantly more than EN and VA. The 3 tested materials showed similar roughness, wear, and abrasiveness when opposed by the same material.

Effect of layer thickness and polishing on wear resistance of additively manufactured occlusal splints

OBJECTIVE

To evaluate the effect of polishing and layering thickness on the wear resistance of 3D-printed occlusal splint materials.

METHODS

Specimens with 3 different layer thicknesses (50, 75, 100 µm) were produced in the form of a disc 3 mm thick using V-Print splint resin on a 3D-printer with digital light processing technology. (n = 16 for each thickness) All specimens were washed and cured according to the manufacturer's instructions. Half of the specimens of each layer thickness were polished with silicon carbide papers. All specimens were subjected to 120.000 cycles of a chewing simulator for 2-body wear tests. Before and after the wear test, the specimens were scanned with a laser scanner, and the images were overlaid using a 3D analysis program and the volume loss was calculated. The wear patterns of the specimens were examined under a scanning electron microscope. Statistical evaluation was performed using a Shapiro-Wilk test, 2-way ANOVA, 1-way ANOVA, and Tukey post hoc test (α = 0.05).

RESULTS

While polishing had a significant effect (p = 0.003) on the wear volume of the occlusal splints, layer thickness (p = 0.105) and their interaction between polishing and layer thickness (p = 0.620) did not significantly affect the wear volume. Regardless of the polishing, the lowest mean wear was observed for D50 (0.064 mm3), followed by D75 (0.078 mm3), and D100 (0.096 mm3). However, a significant difference was observed only between polished D50 and unpolished D100.

CONCLUSION

The polished 3D-printed occlusal splint resin showed higher wear resistance than the unpolished one, regardless of the layer thickness.

CLINICAL SIGNIFICANCE

Since different layer thicknesses of 50 µm and greater had no effect on the wear resistance of the material, a layer thickness of 100 µm may be preferred for faster printing. However, polishing occlusal splints may reduce the amount of wear and improve clinical performance.

CAD-CAM resin-ceramic material wear: A systematic review

STATEMENT OF PROBLEM

The increasing use of computer-aided design and computer-aided manufacturing (CAD-CAM) systems has led to the development of resin-ceramic materials that meet the requirements of minimally invasive dentistry, including the resin nanoceramic (RNC) and polymer-infiltrated ceramic network (PICN). The wear characteristics of these materials are unclear.

PURPOSE

The purpose of this systematic review was to compare the wear resistance of resin-ceramic materials when compared with one another or with lithium disilicate glass-ceramics.

MATERIAL AND METHODS

The PubMed, Scopus, and DOSS search engines were used to identify articles published between 2013 and 2021. Two independent researchers conducted the systematic review by following the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines and by following a combination of keywords.

RESULTS

Of a total of 310 articles, 26 were selected, including only 1 clinical study. Among these, 15 compared resin-ceramic materials with each other, while 11 compared resin-ceramic materials with lithium disilicate ceramics. Two types of wear were used to compare the materials: attrition and abrasion. The most commonly studied materials were 2 RNCs (Lava Ultimate and Cerasmart), 1 PICN (Vita Enamic), and 1 ceramic (IPS e.max CAD). Among the resin-ceramic materials, the PICN (Vita Enamic) showed less wear than the RNCs. Of the RNCs, Cerasmart had less attrition wear and less wear of the opposing teeth.

CONCLUSIONS

Lithium disilicate glass-ceramics have a higher wear resistance than resin-ceramic materials, but they cause more wear of the opposing teeth.

Biofilm Formation on Hybrid, Resin-Based CAD/CAM Materials for Indirect Restorations: A Comprehensive Review

Hybrid materials are a recent addition in the field of restorative dentistry for computer-aided design/computer-aided manufacturing (CAD/CAM) indirect restorations. The long-term clinical success of modern dental restorative materials is influenced by multiple factors. Among the characteristics affecting the longevity of a restoration, the mechanical properties and physicοchemical interactions are of utmost importance. While numerous researchers constantly evaluate mechanical properties, the biological background of resin-based CAD/CAM biomaterials is scarcely investigated and, therefore, less described in the literature. This review aims to analyze biofilm formation on the surfaces of novel, hybrid, resin-based CAD/CAM materials and evaluate the methodological protocols followed to assess microbial growth. It is demonstrated that the surface structure, the composition and the finishing and polishing procedures on the surface of a dental restorative material influence initial bacterial adhesion; however, most studies focus on in vitro protocols, and in vivo and/or in situ research of microbiomics in CAD/CAM restorative materials is lacking, obstructing an accurate understanding of the bioadhesion phenomenon in the oral cavity.

In vitro evaluation of CAD/CAM composite materials

OBJECTIVES

The purpose of this in vitro study was to evaluate the microstructural, elemental and mechanical properties of contemporary computer-aided-design/computer-aided manufacturing (CAD/CAM) resin based composite (RBC) materials.

METHODS

Six CAD/CAM RBC materials [Brilliant CRIOS (Coltene Whaledent AG), Cerasmart (GC), Lava Ultimate (3M ESPE), Tetric CAD (Ivoclar Vivadent), Shofu Block HC (Shofu), Grandio Blocs (VOCO GmbH)] were tested. Ten rectangular blocks (14 Χ 12 Χ 18 mm) for each material, after metallographic grinding and polishing, were subjected to Instrumented Indentation Testing (ΙIT). Martens Hardness (HM), Indentation Elastic Modulus (EIT), Elastic (ηIT) and Creep indices (CIT) were determined according to formulas provided by ISO 14577. The diagonal length of each indentation was measured and HV was determined. The results of HM, EIT, ηΙΤ, HV, and CIT were statistically analyzed by one-way ANOVA and Tukey post hoc test employing the material as a discriminating variable (a = 0.05), while the possible correlations were determined by Spearman's correlation test. One specimen from each group was examined by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX).

RESULTS

Backscattered Electron images and EDX analysis demonstrated differences in size, shape and type of fillers along with elemental composition among materials tested. Statistical significant differences were identified for all mechanical properties tested. Grandio Blocs had the significantly higher HM (953±7 N/mm2), HV (136±1) and EIT (23±1 GPa) followed by Lava Ultimate (ΗM=674±25 N/mm2, HV=105±2, EIT=15±1 GPa). Elastic index ranged from 41% to 52%, with Shofu Block demonstrating the significantly highest ηIT (52 ± 1%) values. Cerasmart had significantly higher CIT value (8.4 ± 0.1%) than all other materials tested, while Grandio Blocs and Lava Ultimate had the lowest ones. Spearman's correlation revealed that all mechanical properties tested exhibited correlations with each other, apart from ηΙΤ.

CONCLUSIONS

The results showed that the CAD/CAM materials tested have differences in their microstructure, elemental composition and mechanical properties.

CLINICAL SIGNIFICANCE

The RBCs tested showed significant differences in mechanical properties and thus differences in clinical performance are anticipated. RBCs with increased filler loading had the most favorable combination of hardness, elastic modulus and creep index indicating that these materials may have better clinical performance under intraoral loading conditions.

Effect of aging on color, gloss and surface roughness of CAD/CAM composite materials

OBJECTIVES

To assess the effect of aging procedures on color, gloss and surface roughness of CAD/CAM composite materials.

METHODS

6 CAD/CAM composite materials (Brilliant CRIOS, Cerasmart, Lava Ultimate, Tetric CAD, Shofu Block HC, Grandio Blocs) were tested. 10 CAD/CAM fabricated specimens of each material polished according to manufacturers' recommendations, were subjected to one of the following aging procedures; immersion in coffee (30 days, 37^οC), water thermocycling (5000 cycles, 5-55 °C) and photoaging (150,000 kJ/m²). Color, gloss and surface roughness measurements were performed before and after aging and the respective changes were calculated. Kruskal-Wallis tests, paired t-tests, one-way ANOVA and Bonferroni post-hoc tests were used for statistical analysis (a = 0.05).

RESULTS

Color changes ranged from 3.03 to 4.13 after coffee immersion, from 1.33 to 2.55 after thermocycling and from 1.02 to 2.75 after photoaging. No statistically significant differences for ΔE*_ab were found among materials after coffee immersion and thermocycling (p>0.05). Gloss changes ranged from -5.7 to -1.6 GU after coffee immersion, from -2.3 to 0.1 GU after thermocycling and from -4.4 to 0.5 GU after photoaging. No significant differences in gloss changes were found among materials after aging (p>0.05). Tetric CAD demonstrated the significantly lower gloss and the higher surface roughness after polishing. Except for gloss after thermocycling, aging procedures caused significant alteration of gloss and surface roughness parameters from baseline levels.

CONCLUSIONS

Aging procedures caused perceptible but acceptable color changes and small but visible gloss changes, while surface roughness parameters of the tested CAD/CAM composite materials were significantly affected by aging.

CLINICAL SIGNIFICANCE

Aging procedures affected CAD/CAM composite materials indicating that these materials may be prone to color and surface alterations in the oral environment that could compromise the esthetics and the performance of the restorations. Clinical studies are needed to investigate the long-term behavior of the newly introduced CAD/CAM materials.

Comparative study on the impact-sliding wear behaviour of CAD/CAM resin-ceramic materials and tooth enamel

OBJECTIVES

To compare the impact-sliding wear of different CAD/CAM resin-ceramic materials and tooth enamel, and explore the corresponding wear damage mechanism.

METHODS

Human tooth enamel (EN), Vita ENAMIC (Vita, VE), Lava Ultimate (3 M, LU), and GC CERASMART (GC, CS) were used in this study. The hardness, elastic modulus, and roughness values of the samples were measured. Further, impact-sliding wear tests were performed in a ball-on-flat configuration with spherical zirconia antagonists and the coefficients of friction (CoF) were recorded simultaneously. Additionally, a white light interferometer was used to determine the volume losses and scanning electron microscopy was used to observe the wear morphology of the wear scars and the damage feature in the vertical sections to clarify the damage mechanism during the impact-sliding wear test.

RESULTS

EN exhibited the highest elastic modulus and CoF, followed by VE, LU, and CS. The hardness and roughness of EN and VE were similar and were higher than those of LU and CS. Throughout the wear tests, VE exhibited the highest volume loss, whereas CS exhibited the lowest. The wear damage characteristics of VE were similar to those of EN, displaying brittle fractures of inorganic substances and plastic deformation of organic substances in the impact part, exhibiting plough marks in the sliding parts. In the case of LU and CS, the entire wear areas displayed plastic deformation of the resin matrix, exfoliation of the filler particles, and plough marks.

SIGNIFICANCE

Enamel and polymer-infiltrated ceramic network materials exhibit similar wear damage modes. Additionally, the high-density nanocomposite resin material is the most resistant to impact-sliding wear from a tribological perspective.

Digital Volumetric Analysis of CAD/CAM Polymeric Materials after Tooth Brushing

The objective of the study was to evaluate the volumetric wear of four composite materials for CAD/CAM (computer-aided design/computer-aided manufacturing) systems. The materials evaluated were: Cerasmart (CER), Shofu Block HC (SBH), Tetric CAD (TEC) and Brava (BRA). All the samples (n = 40) were subjected to simulated brushing (100,000 cycles). Wear was evaluated by superimposing pre-and post-brushing scans obtained with an intraoral optical scanner (CEREC Primescan; Dentsply Sirona, Germany), which were subsequently imported into the OraCheck software 5.0 (Dentsply Sirona, Germany). The data were analyzed by ANOVA test and Tukey’s HSD test was used for multiple comparisons. Cerasmart showed the least wear after brushing. All the tested materials exhibited mass loss.

Martens Hardness of CAD/CAM Resin-Based Composites

(1) Background: The properties of CAD/CAM resin-based composites differ due to differences in their composition. Instrumented indentation testing can help to analyze these differences with respect to hardness, as well as energy-converting capabilities due to viscoelastic behavior. (2) Methods: Eleven materials were investigated using instrumented indentation testing. Indentation depth (hr), Martens hardness (HM), indentation hardness (HIT), indentation modulus (EIT), the elastic part of indentation work (ηIT), and indentation creep (CIT) were investigated, and statistical analysis was performed using one-way ANOVA, Bonferroni post-hoc test, and Pearson correlation (α = 0.05). (3) Results: All of the investigated parameters revealed differences between the analyzed materials. Besides the differences in hardness-associated parameters (hr, HM, and HIT), instrumented indentation testing demonstrated differences in energy-converting properties. The subsequent one-way ANOVA revealed significant differences (p < 0.001). A significant (p < 0.01, Pearson correlation >0.576) correlation between the materials and HM, HIT, or EIT was identified. (4) Conclusions: Due to the differences found in the energy-converting properties of the investigated materials, certain CAD/CAM resin-based composites could show superior stress-breaking capabilities than others. The consequential reduction in stress build-up may prove to beneficial, especially for implant-retained restorations or patients suffering from parafunctions.

Friction and wear behavior of chairside CAD-CAM materials against different types of antagonists: An in vitro study

STATEMENT OF PROBLEM

Studies on the friction and wear behavior of recently introduced chairside computer-aided design and computer-aided manufacture (CAD-CAM) restorative materials are lacking.

PURPOSE

The purpose of this in vitro study was to evaluate the wear behavior of chairside CAD-CAM materials against different types of antagonists (human tooth enamel, composite resin, and feldspathic porcelain).

MATERIAL AND METHODS

Specimens (14×14×2 mm) of different CAD-CAM materials (Brilliant Crios, Lava Ultimate, Vita Enamic, Vita Suprinity) were obtained by using a low-speed precision cutter (n=10). Wear tests were performed with a 20-N load, 2.5-mm/s sliding speed, 1-mm sliding distance, and 1500 cycles via a tribometer according to ASTM-G133. The coefficient of friction (CoF) of the material pairs was measured and recorded by using a special software program. Surface roughness (Ra), maximum wear depth, and mean maximum wear depth were measured with a profilometer, and values were analyzed by using 2-way ANOVA and the Bonferroni correction. Vickers hardness of CAD-CAM specimens was determined with a microhardness tester. Microhardness values were analyzed by using 1-way ANOVA and Tukey post hoc tests. Worn surfaces were observed by scanning electron microscopy and a 3D noncontact profilometer to determine the wear pattern and primary wear mechanisms.

RESULTS

Significant differences were found in the interactions between CAD-CAM materials and different types of antagonists (P<.001) for maximum wear depth, mean maximum wear depth, CoF, and Ra values.

CONCLUSIONS

Vita Suprinity exhibited superior wear resistance and Ra against all antagonists compared with other CAD-CAM materials. However, Vita Suprinity increased the destructive effects on antagonists. The safety of CAD-CAM materials is best determined when the wear behavior of materials and their effect on the antagonist are evaluated together.

Wear behavior of current computer-aided design and computer-aided manufacturing composites and reinforced high performance polymers: An in vitro study

OBJECTIVE

To analyze the wear rate of computer-aided design and computer-aided manufacturing (CAD/CAM) composites, polyetheretherketones and glass ceramics.

MATERIAL AND METHODS

Our study groups were prepared from two different resin-based composites (Brillant Crios, Cerasmart), a glass ceramic (IPS Emax CAD) and reinforced polyetheretherketone (BioHPP) material (n = 10). Premolar teeth were used as antagonists. The specimens, which were subjected to two body wear tests (240,000 cycles, 1.2 Hz, 50N) in the chewing simulator, were scanned with a 3D laser scanner both before and after the wear test. Volume loss and wear depth were determined by means of the obtained images software program. The wear pattern was examined by scanning electron microscopy. Kruskal Wallis test served for analyzing.

RESULTS

The least volume loss and wear depth were seen in the polyetheretherketone material (0.06 ± 0.04 mm³ , 0.02 ± 0.01 mm), while the maximum volume loss was seen in the groups containing resin-based composite. (p = 0.05). The volume loss value in glass ceramics is between CAD/CAM composites and polyetheretherketone.

CONCLUSION

The behavior of polyetheretherketone against enamel was different from glass ceramics and composite materials in terms of the amount of wear.

CLINICAL SIGNIFICANCE

Polyetheretheketone can be considered as an alternative to other chairside materials in terms of wear resistance.

Correlation between microhardness and wear resistance of dental alloys against monolithic zirconia

PURPOSE

The aim of this study is to compare the hardness according to the conditions of metal alloys. Moreover, the correlation between the cast crown hardness before and after wear testing and the degree of wear for each dental alloy was assessed.

MATERIALS AND METHODS

Cast crowns of three metal alloys (Co-Cr, gold, and Ni-Cr alloys) opposing smooth-surface monolithic zirconia were used. The Vickers microhardness of the ingot (which did not undergo wear testing) and the cast crown before and after wear testing were measured for each alloy. Two-way ANOVA and Scheffé tests were used to compare the measured hardness values. Moreover, the Pearson correlation coefficient was used to evaluate the relationship between the surface hardness and the wear of the cast crown (α=.05).

RESULTS

There was no significant difference in the hardness before and after wear testing for the gold alloy (P>.05); however, the hardness of the worn surface of the cast crown increased compared to that of the cast crown before the wear tests of Ni-Cr and Co-Cr alloys (P<.05). Furthermore, there was no correlation between the wear and hardness of the cast crown before and after wear testing for all three metal alloys (P>.05).

CONCLUSION

There was a significant difference in hardness between dental alloys under the same conditions. No correlation existed between the surface hardness of the cast crown before and after wear testing and the wear of the cast crown.

Flexural strength, fracture toughness, three-body wear, and Martens parameters of pressable lithium-X-silicate ceramics

OBJECTIVES

To test and compare five pressable lithium-X-silicate-ceramics on their mechanical and wear properties.

METHODS

Specimens were pressed and prepared from: i. Amber Press (AP), ii. Celtra Press (CP), iii. Initial LiSi Press (IL), iv. Livento Press (LP), and v. IPS e.max Press (IE). Four-point flexural strength (FS), SEVNB fracture toughness (K_IC), three-body wear (3BW), Martens hardness (HM) and indentation modulus (E_IT) were measured. For CP, FS and HM were measured with and without additional Power Firing. Each subgroup contained 15 specimens. Data were analyzed using Kolmogorov-Smirnov, one-way ANOVA followed by Scheffé test, Kruskal-Wallis-H-, Mann-Whitney-U-, and Spearman-Rho-test (p < 0.05). The Weibull modulus was calculated using the maximum likelihood estimation method.

RESULTS

AP and CP presented higher FS than IL. LP presented the highest Weibull modulus. CP showed lower K_IC values than AP, and AP was not significant compared to LP and IE. The most 3BW material loss was observed for CP. CP revealed higher HM values than the remaining ceramics. IL presented lower E_IT compared to AP and CP. The following correlations were observed between the test parameters: 3BW with FS (r = 0.279, p = 0.015), with HM (r = -0.378, p = 0.001), and with E_IT (r = -0.344, p = 0.004); E_IT with FS (r = 0.203, p = 0.028); and HM with FT (r = -0.223, p = 0.027) and E_IT (r = 0.884, p < 0.001). No correlations were observed between FS and K_IC (r = 0.046; p = 0.346).

SIGNIFICANCE

AP followed by LP showed the highest and IL followed by CP the lowest properties tested. Power Firing of CP improved the flexural strength. Ceramics with high flexural strength and Martens parameters showed lower wear. Materials with high Martens hardness presented lower fracture toughness values and ones with high indentation modulus showed high flexural strength.

Effect of zirconia polycrystal and stainless steel on the wear of resin composites, dentin and enamel

This study evaluated the effect of two antagonist substrates (Y-TZP/zirconia or stainless steel) on the wear rate and surface alterations of different composite materials and bovine tooth substrates (enamel and dentin). The wear rate of different composite materials (n = 20; two direct composite resins: HelioMolar - HM; Clearfil AP-X - CAP, three indirect composite resins: Estenia C&B - EST; Adoro - ADO; Sinfony - SFY, and one composite resin for direct/indirect restorations: Filtek Z250 - Z250), bovine enamel and dentin against two different antagonist materials (zirconia or stainless steel) into two mediums (two-body and three-body wear) were collected. After wear tests on ACTA wear machine, Scanning Electron Microscopy (SEM) analysis was performed to access the surface alterations. The wear data were evaluated by three-way ANOVA and Tukey post-hoc test (α = 0.05). The factors 'antagonist', 'medium', 'restorative materials', and the interaction of all factors grouped by two and integrated showed statistical significance on the wear rates. A two-body test depicted no difference among all composites and enamel for wear rate, while a three-body test depicted differences among composites directly related to the filler content: EST < Z250 = CAP < ADO = HM < SFY. Dentin always showed the highest wear rates and enamel the lowest rates. The presence of food bolus (three-body test) led to higher wear rates in comparison to an only aqueous medium (two-body test). SEM analysis showed that different materials present specific wear patterns, regardless of the medium and the antagonist considered. Differently from enamel, dentin substrate was intensively prone to wear, regardless of the antagonist/medium. Resin composite substrates presented intermediate wear rates, depending directly on their filler content (% in weight).