Comparative assessment of relapse and failure between CAD/CAM stainless steel and standard stainless steel fixed retainers in orthodontic retention patients:

ABSTRACT Objectives To compare relapse and failure rates of computer-aided design/computer-aided manufacturing (CAD/CAM) and standard fixed retainers. Materials and Methods This single-center, single-blinded, prospective randomized clinical trial included 46 patients who completed active orthodontic treatment and complied with retention visits. The patients were randomly assigned to three groups: CAD/CAM group with multistranded stainless steel wires (CAD/CAM, n = 16), Lab group with the same multistranded wires (lab, n = 16), and control group with stainless steel Ortho-FlexTech wires (traditional, n = 14). Intraoral scans were obtained at placement of fixed retainers (T1), 3-month visit (T2), and 6-month visit (T3) and measured for intercanine width and Little's Irregularity Index. Failures were recorded. Results The CAD/CAM group experienced less intercanine width decrease than the traditional group at 3 months (mean difference, 0.83 ± 0.16 mm; 95% confidence interval [CI], 0.44–1.22; P < .001) and 6 months (mean difference, 1.23 ± 0.40 mm; 95% CI, 0.19–2.27; P < .05). The CAD/CAM group experienced less increase in Little's Irregularity Index compared with the lab group within 3 months (mean difference, 0.81 ± 0.27 mm; 95% CI, 0.12–1.49; P < .05). Failures from greatest to least were experienced by the lab group (43.8%), the CAD/CAM group (25%), and the traditional group (14.3%). Conclusions Within 6 months of bonding fixed retainers, CAD/CAM fixed retainers showed less relapse than lab-based and traditional chairside retainers and less failures than lab-based retainers.

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Evaluation of Polishing Systems for CAD/CAM Polymer-Infiltrated Ceramic-Network Restorations

Operative Dentistry ◽

10.2341/20-006-l ◽

2021 ◽

Author(s):

CA Jurado ◽

A Tsujimoto ◽

H Watanabe ◽

NG Fischer ◽

JA Hasslen ◽

...

Keyword(s):

Surface Roughness ◽

Computer Aided Design ◽

Dental Students ◽

Faculty Members ◽

Dental School ◽

Control Group ◽

Significant Difference ◽

Computer Aided ◽

Cad Cam ◽

A Company

SUMMARY Objective: The purpose of this study was to evaluate the effectiveness of five different polishing systems on a computer-aided design and computer-aided manufacturing (CAD/CAM) polymer-infiltrated ceramic-network restoration with nanoscale assessment using atomic force microscopy (AFM) and visual assessment performed by dental school senior students and faculty members. Method: Forty-eight full coverage crowns were milled out of polymer-infiltrated ceramic-network CAD/CAM blocks (Vita Enamic) for polishing with one company proprietary, two ceramic and two composite polishing systems. The prepared crowns were divided into six groups: (1) no polishing (control); (2) polishing with Vita Enamic Polishing Kit (VEna); (3) polishing with Shofu Porcelain Laminate Polishing Kit (SCer); (4) polishing with Brasseler Dialite Feather lite All- Ceramic Adjusting & Polishing System (BCer); (5) polishing with Shofu Composite Polishing Kit (SCom); and (6) polishing with Brasseler Composite Polishing Kit (BCom). The polished crown surface topography was observed, and surface roughness and area were measured with AFM. In addition, polished crowns were visually assessed by 15 senior dental students and 15 dental school faculty members. Results: All polishing treatments significantly reduced the surface roughness and area of the crown compared with the control. SCom and BCom showed significantly higher surface area than VEna, and the SCer and BCer groups were intermediate, showing no significant difference from either VEna or SCom and BCom. There were no significant differences in surface roughness between any of the systems. Dental students and faculty members classified the groups polished with VEna, SCer, and BCer groups as clinically acceptable, and they selected BCer group as the best polished restorations and the control group as the least polished restorations. Conclusions: Ceramic and composite polishing systems produced similar polishing results as that observed using a company proprietary polishing system. However, effectiveness for polishing using a company proprietary and ceramic polishing system tends to be higher than composite polishing systems.

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Effects of Polishing Bur Application Force and Reuse on Sintered Zirconia Surface Topography

Operative Dentistry ◽

10.2341/17-105-lr ◽

2018 ◽

Vol 43 (4) ◽

pp. 437-446 ◽

Cited By ~ 2

Author(s):

NG Fischer ◽

A Tsujimoto ◽

AG Baruth

Keyword(s):

Surface Topography ◽

Computer Aided Design ◽

Groove Depth ◽

Control Group ◽

Limited Information ◽

Average Roughness ◽

Significant Difference ◽

Computer Aided ◽

Cad Cam

SUMMARY Objective: Limited information is available on how to polish and finish zirconia surfaces following computer-aided design/computer-aided manufacturing (CAD/CAM), specifically, how differing application forces and reuse of zirconia polishing systems affect zirconia topography. Purpose: To determine the effect of differing, clinically relevant, polishing application forces and multiple usages of polishing burs on the surface topography of CAD/CAM zirconia. Methods: One hundred twenty 220-grit carbide finished zirconia disks were sintered according to manufacturer's directions and divided into two groups for the study of two coarse polishing bur types. Each group was divided into subgroups for polishing (15,000 rpm) at 15 seconds for 1.0 N, 4.5 N, or 11 N of force using a purpose-built fixture. Subgroups were further divided to study the effects of polishing for the first, fifth, 15th, and 30th bur use, simulating clinical procedures. Unpolished surfaces served as a control group. Surfaces were imaged with noncontact optical profilometry (OP) and atomic force microscopy (AFM) to measure average roughness values (Ra). Polishing burs were optically examined for wear. Scanning electron microscopy (SEM) was performed on burs and zirconia surfaces. One-way ANOVA with post hoc Tukey HSD (honest significant difference) tests (α=0.05) were used for statistical analyses. Results: AFM and OP Ra values of all polished surfaces were significantly lower than those of the unpolished control. Different polishing forces and bur reuse showed no significant differences in AFM Ra. However, significant differences in OP Ra were found due to differing application forces and bur reuse between the first and subsequent uses. SEM and optical micrographs revealed notable bur wear, increasing with increasing reuse. SEM and AFM micrographs clearly showed polished, periodic zirconia surfaces. Nanoscale topography, as analyzed with kurtosis and average groove depth, was found dependent on the specific polishing bur type. Conclusions: These in vitro results suggest changes in OP Ra due to bur reuse and polishing application force. Within the parameters of this study, the resultant topography of zirconia polishing is force-dependent and the reuse of coarse polishing burs is possible without statistically significant differences in Ra values after initial use. Nanoscale and microscale topography were shown to depend on specific polishing bur type.

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Evaluation of the light transmission of chairside polymer infiltrated hybrid ceramics in different shades and thicknesses

Journal of Applied Biomaterials & Functional Materials ◽

10.1177/2280800018807109 ◽

2019 ◽

Vol 17 (1) ◽

pp. 228080001880710 ◽

Cited By ~ 1

Author(s):

İbrahim Duran ◽

Necati Kaleli ◽

Çağrı Ural ◽

İdris Kavut

Keyword(s):

Computer Aided Design ◽

Light Transmission ◽

Univariate Analysis ◽

Control Group ◽

Significant Difference ◽

Computer Aided ◽

Cad Cam ◽

Lower Light ◽

Hybrid Ceramic

Background: This in vitro study aimed to evaluate the amount of polymerizing light passing through hybrid ceramic specimens in different shades and thicknesses. Methods: Rectangular-shaped feldspathic ceramic computer aided design and computer aided manufacturing (CAD-CAM) blocks and translucent and high translucent polymer infiltrated hybrid ceramic CAD-CAM blocks in four different shades (1M1, 1M2, 2M2, and 3M2) were sectioned in four different thicknesses (0.8, 1.5, 2, and 3 mm), and a total of 48 groups ( n = 10) were obtained. Feldspathic ceramic specimens served as the control group. The light transmission of each ceramic specimen was measured three times by using a light-emitting diode and a radiometer. Data were statistically analyzed by using univariate analysis of variance (ANOVA) followed by one-way ANOVA, Tukey honest significant difference, and Tamhane T2 tests (α = 0.05). Results: Translucent polymer infiltrated hybrid ceramic specimens exhibited significantly ( p < 0.001) lower light transmission values than high translucent polymer infiltrated hybrid ceramic and feldspathic ceramic specimens, whereas feldspathic ceramic specimens exhibited significantly ( p < 0.001) higher light transmission than translucent and high translucent polymer infiltrated hybrid ceramic specimens. The amount of light transmission significantly ( p < 0.05) decreased when the shade value decreased and the thickness increased. Conclusions: Polymer infiltrated hybrid ceramic specimens showed lower light transmission values than feldspathic ceramic specimens, and the amount of light transmission was affected by the ceramic shade and thickness.

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Effect of Different Computer-aided Design/Computer-aided Manufacturing (CAD/CAM) Materials and Thicknesses on the Fracture Resistance of Occlusal Veneers

Operative Dentistry ◽

10.2341/17-131-l ◽

2018 ◽

Vol 43 (5) ◽

pp. 539-548 ◽

Cited By ~ 9

Author(s):

JP Andrade ◽

D Stona ◽

HR Bittencourt ◽

GA Borges ◽

LH Burnett ◽

...

Keyword(s):

Computer Aided Design ◽

Fracture Resistance ◽

Testing Machine ◽

Control Group ◽

Computer Aided Manufacturing ◽

Universal Testing ◽

Computer Aided ◽

Cad Cam ◽

Aided Design

SUMMARY The aim was to evaluate, in vitro, the influence of different computer-aided design/computer-aided manufacturing (CAD/CAM) materials (IPS e.max CAD, Vita Enamic, and Lava Ultimate) and thicknesses (0.6 mm and 1.5 mm) on the fracture resistance of occlusal veneers. Sixty human third molars were prepared to simulate advanced erosion of the occlusal surface, and the teeth were randomly divided into six experimental groups (n=10) according to the material and thickness used to build the veneers. Ten sound teeth formed the control group. The veneers were adhesively luted and submitted to mechanical cyclic loading (1 million cycles at 200-N load). The fracture resistance test was performed in a universal testing machine. The failures were classified as “reparable” and “irreparable.” According to two-way analysis of variance and the Tukey test, the interaction (material × thickness) was significant (p=0.013). The highest fracture resistance was obtained for IPS e.max CAD at a 1.5-mm thickness (4995 N) and was significantly higher compared to the other experimental groups (p<0.05). The lowest fracture resistance was obtained for Vita Enamic at 0.6 mm (2973 N), although this resistance was not significantly different from those for IPS e.max CAD at 0.6 mm (3067 N), Lava Ultimate at 0.6 mm (3384 N), Vita Enamic at 1.5 mm (3540 N), and Lava Ultimate at 1.5 mm (3584 N) (p>0.05). The experimental groups did not differ significantly from the sound teeth (3991 N) (p>0.05). The failures were predominantly repairable. The occlusal veneers of IPS e.max CAD, Vita Enamic, and Lava Ultimate, with thicknesses of 0.6 mm and 1.5 mm, obtained fracture resistances similar to those associated with sound teeth.

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Evaluation of the Surface Characteristics of Dental CAD/CAM Materials after Different Surface Treatments

Materials ◽

10.3390/ma13040981 ◽

2020 ◽

Vol 13 (4) ◽

pp. 981 ◽

Cited By ~ 1

Author(s):

Konstantinos Papadopoulos ◽

Kimon Pahinis ◽

Kyriaki Saltidou ◽

Dimitrios Dionysopoulos ◽

Effrosyni Tsitrou

Keyword(s):

Surface Roughness ◽

Computer Aided Design ◽

Surface Characteristics ◽

Surface Treatments ◽

Control Group ◽

Composition And Structure ◽

Computer Aided ◽

Need To Evaluate ◽

Cad Cam ◽

Materials Used

Computer-aided design/computer-aided manufacturing (CAD/CAM) technology was developed to ensure the sufficient strength of tooth restorations, to improve esthetic restorations with a natural appearance and to make the techniques easier, faster and more accurate. In the view of the limited research on the surface treatments of the CAD/CAM materials and the need to evaluate the ideal surface characteristics of a material to achieve the best adhesion to tooth tissues, this study aimed to investigate the surface roughness and morphology of four different CAD/CAM materials using four different surface treatments. The CAD/CAM materials used in this study were three composites (Shofu Block HC, Lava Ultimate and Brilliant Crios) and a hybrid ceramic (Enamic). The surface of the specimens of each material received one of the following treatments: no surface treatment, sandblasting with 29 μm Al2O3 particles, 9% hydrofluoric acid etching and silane application, and the tribochemical method using CoJet System. Surface roughness was evaluated using optical profilometry, and surface morphology was observed by means of scanning electron microscopy. All surface treatments resulted in higher surface roughness values compared to the control group. Different treatments affected the surface properties of the materials, presumably due to discrepancies in their composition and structure.

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Influence of Thermal Cycling on Flexural Properties and Simulated Wear of Computer-aided Design/Computer-aided Manufacturing Resin Composites

Operative Dentistry ◽

10.2341/16-046-l ◽

2017 ◽

Vol 42 (1) ◽

pp. 101-110 ◽

Cited By ~ 20

Author(s):

A Tsujimoto ◽

WW Barkmeier ◽

T Takamizawa ◽

MA Latta ◽

M Miyazaki

Keyword(s):

Stainless Steel ◽

Thermal Cycling ◽

Computer Aided Design ◽

Flexural Properties ◽

Resin Composites ◽

Thermal Cycles ◽

Computer Aided Manufacturing ◽

Computer Aided ◽

Cad Cam ◽

Aided Design

SUMMARY Objective: The purpose of this study was to evaluate the influence of thermal cycling on the flexural properties and simulated wear of computer-aided design/computer-aided manufacturing (CAD/CAM) resin composites. Methods: The six CAD/CAM resin composites used in this study were 1) Lava Ultimate CAD/CAM Restorative (LU); 2) Paradigm MZ100 (PM); 3) CERASMART (CS); 4) Shofu Block HC (SB); 5) KATANA AVENCIA Block (KA); and 6) VITA ENAMIC (VE). Specimens were divided randomly into two groups, one of which was stored in distilled water for 24 hours, and the other of which was subjected to 10,000 thermal cycles. For each material, 15 specimens from each group were used to determine the flexural strength and modulus according to ISO 6872, and 20 specimens from each group were used to examine wear using a localized wear simulation model. The test materials were subjected to a wear challenge of 400,000 cycles in a Leinfelder-Suzuki device (Alabama machine). The materials were placed in custom-cylinder stainless steel fixtures, and simulated localized wear was generated using a stainless steel ball bearing (r=2.387 mm) antagonist in a water slurry of polymethyl methacrylate beads. Simulated wear was determined using a noncontact profilometer (Proscan 2100) with Proscan and AnSur 3D software. Results: The two-way analysis of variance of flexural properties and simulated wear of CAD/CAM resin composites revealed that material type and thermal cycling had a significant influence (p<0.05), but there was no significant interaction (p>0.05) between the two factors. The flexural properties and maximum depth of wear facets of CAD/CAM resin composite were different (p<0.05) depending on the material, and their values were influenced (p>0.05) by thermal cycling, except in the case of VE. The volume losses in wear facets on LU, PM, and SB after 10,000 thermal cycles were significantly higher (p<0.05) than those after 24 hours of water storage, unlike CS, KA, and VE. Conclusion: The results of this study indicate that the flexural properties and simulated wear of CAD/CAM resin composites are different depending on the material. In addition, the flexural properties and simulated wear of CAD/CAM resin composites are influenced by thermal cycling.

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Differences in Radiopacity, Surface Properties, and Plaque Accumulation for CAD/CAM-Fabricated vs Conventionally Processed Polymer-based Temporary Materials

Operative Dentistry ◽

10.2341/19-057-l ◽

2019 ◽

Vol 45 (4) ◽

pp. 407-415 ◽

Cited By ~ 1

Author(s):

P Nassary Zadeh ◽

N Lümkemann ◽

M Eichberger ◽

B Stawarczyk ◽

M Kollmuss

Keyword(s):

Surface Roughness ◽

Free Energy ◽

Surface Free Energy ◽

Computer Aided Design ◽

Control Group ◽

Actinomyces Naeslundii ◽

Gingival Health ◽

Computer Aided ◽

Cad Cam ◽

Aided Design

Clinical Relevance As temporary materials are often used in prosthetic dentistry, there is need to investigate their behavior in the oral environment. Parameters such as surface roughness and surface free energy correlate to the level of plaque adhesion, which can impact gingival health. SUMMARY Objective: To test computer-aided design/computer-aided manufacturing (CAD/CAM)-fabricated and conventionally processed polymer-based temporary materials in terms of radiopacity (RO), surface free energy (SFE), surface roughness (SR), and plaque accumulation (PA). Methods and Materials: Six temporary materials (n=10/n=10) were tested, including three CAD/CAM-fabricated (CC) materials—Art Bloc Temp (CC-ABT), Telio CAD (CC-TC), and VITA CAD Temp (CC-VCT)—and three conventionally processed (cp) materials: Integrity Multi Cure (cp-IMC), Luxatemp Automix Plus (cp-LAP), and Protemp 4 (cp-PT4). Zirconia acted as the control group (CG, n=10). RO was evaluated according to DIN EN ISO 13116. SFE was investigated using contact angle measurements. SR was measured using a profilometer. The PA tests were performed using three microorganisms: Streptococcus mutans, Actinomyces naeslundii, and Veillonella parvula. Data were analyzed using Kolmogorov-Smirnov, Kruskal-Wallis, Mann-Whitney U-, Dunn-Bonferroni, Wilcoxon, Levene, and Pearson tests and one-way analysis of variance with post hoc Scheffé test (α=0.05). Results: No radiopacity was observed for any CC material or cp-PT4. CG showed the highest RO, while no differences between cp-IMC and cp-LAP were found. CG showed lower SFE compared to all polymer temporary materials, except in the case of CC-TC. cp-LAP and cp-IMC presented higher SFE than did CC-TC and CG. CC-ABT presented lower initial SR values compared to cp-PT4 and cp-LAP. For cp-LAP, a higher initial SR was measured than for all CAD/CAM materials and cp-IMC. All specimens showed a certain amount of PA after the incubation period. A naeslundii and V parvula resulted in comparable PA values, whereas the values for S mutans were lower by one log level. CAD/CAM materials showed superior results for SR, SFE, and PA, whereas all materials lacked RO.

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Evaluation of the Color Stability of 3D-Printed Crown and Bridge Materials against Various Sources of Discoloration: An In Vitro Study

Materials ◽

10.3390/ma13235359 ◽

2020 ◽

Vol 13 (23) ◽

pp. 5359

Author(s):

Ji-Won Shin ◽

Jong-Eun Kim ◽

Young-Jin Choi ◽

Seung-Ho Shin ◽

Na-Eun Nam ◽

...

Keyword(s):

3D Printing ◽

Computer Aided Design ◽

Color Change ◽

Color Stability ◽

Control Group ◽

Water Control ◽

Storage Duration ◽

Computer Aided ◽

Cad Cam ◽

3D Printed

Recent advances in three-dimensional (3D) printing have introduced new materials that can be utilized for dental restorations. Nonetheless, there are limited studies on the color stability of restorations using 3D-printed crowns and bridge resins. Herein, the color stability of conventional computer-aided design/computer-aided manufacturing (CAD/CAM) blocks and 3D-printing resins was evaluated and assessed for their degrees of discoloration based on material type, colorant types (grape juice, coffee, curry, and distilled water (control group)), and storage duration (2, 7, and 30 days) in the colorants. Water sorption, solubility, and scanning electron microscope (SEM) analyses were conducted. A three-way ANOVA analysis showed that all three factors significantly affected the color change of the materials. Notably, the discoloration (ΔE00) was significantly higher in all 3D printing resins (4.74–22.85 over the 30 days) than in CAD/CAM blocks (0.64–4.12 over the 30 days) following immersion in all colorants. 3D-printing resins showed color differences above the clinical limit (2.25) following storage for 7 days or longer in all experimental groups. Curry was the most prominent colorant, and discoloration increased in almost all groups as the storage duration increased. This study suggests that discoloration must be considered when using 3D printing resins for restorations.

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Marginal Fit of Implant-Supported All-Ceramic Zirconia Frameworks

Journal of Oral Implantology ◽

10.1563/aaid-joi-d-11-00103 ◽

2013 ◽

Vol 39 (4) ◽

pp. 417-424 ◽

Cited By ~ 12

Author(s):

Hanaa Hassan Zaghloul ◽

Jihan Farouk Younis

Keyword(s):

Cyclic Loading ◽

Computer Aided Design ◽

Control Group ◽

Marginal Gap ◽

Marginal Fit ◽

Mean Values ◽

Significant Difference ◽

All Ceramic ◽

Computer Aided ◽

Cad Cam

This study evaluated the effect of fabrication techniques and cyclic loading on the vertical marginal fit of implant-supported fixed partial denture (FPD) frameworks. Thirty implant-supported 3-unit FPD frameworks were fabricated on a model system, divided into 3 equal groups (n = 10). The first group (control) was constructed from base metal alloy; the other 2 test groups were constructed from all-ceramic zirconia using a computer-aided design/computer-aided manufacturing (CAD/CAM) Cerec 3 system and a copy milling (Zirkonzahn) system. A cyclic load of 200 N was applied to each framework for up to 50,000 cycles. Linear measurements were made in micrometers of the vertical gap between the framework and the implant-supported abutment at 16 predetermined points before and after cyclic loading. The frameworks were viewed using scanning electron microscopy to inspect any fractographic features. One-way analysis of variance was performed to compare the marginal discrepancy values of the control and the 2 test groups and for each group; a t test was applied to determine whether significant changes in the fit were observed after cyclic loading (α = 0.05). The CAD/CAM group showed significantly higher marginal gap mean values (80.58 μm) than the Zirkonzahn and control groups (50.33 μm and 42.27 μm, respectively) with no significant difference. After cyclic loading, the CAD/CAM group recorded the highest marginal gap mean value (91.50 ± 4.260 μm) followed by control group (72.00 ± 2.795 μm); the Zirkonzahn group recorded the lowest marginal gap (65.37 ± 6.138 μm). Cyclic loading significantly increased the marginal gap mean values in the control group only. A marginal chip was observed in one of the CAD/CAM ceramic frameworks. Within the limitations of this study, the fabrication technique influenced the marginal fit of the implant-supported 3-unit FPD frameworks. Cyclic loading failed to change the fit of all-ceramic zirconia frameworks, whereas significant changes were found in the metal frameworks.

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An In-Vitro Study to Evaluate the Effect of Denture Cleansing Agents on Color Stability of Denture Bases Fabricated Using CAD/CAM Milling, 3D-Printing and Conventional Techniques

Coatings ◽

10.3390/coatings11080962 ◽

2021 ◽

Vol 11 (8) ◽

pp. 962

Author(s):

Saurabh Jain ◽

Mohammed Sayed ◽

Walaa Magdy Ahmed ◽

Amjad Hussain Asiri Halawi ◽

Naif Mohammed Ahmed Najmi ◽

...

Keyword(s):

3D Printing ◽

Computer Aided Design ◽

Color Change ◽

Color Stability ◽

Control Group ◽

Denture Base ◽

Computer Aided ◽

Cad Cam ◽

Denture Cleansers

The current literature lacks substantial information about the effect of denture cleansers on the color stability of denture bases formed using Computer-Aided Design/Computer-Aided Manufacturing (CAD/CAM) additive and CAD/CAM subtractive manufacturing techniques. This study aimed to assess the effect of two commercially available denture cleansers on the color stability of denture base resins fabricated using four different techniques. Forty-five disc-shaped specimens were fabricated using each technique. Initial color readings were recorded. Specimens were randomly divided into three subgroups (n = 15): a control group (distilled water) and two denture cleanser groups. They were immersed in these solutions, simulating 180 days of use. Final color readings were recorded. The color difference was calculated, and the data were statistically analyzed. For all the specimens, significant color changes were observed after immersion in denture cleanser solutions. The extent of color change varied according to the type of denture cleanser used. When placed in the denture cleanser solutions, the CAD/CAM subtractive group showed the maximum color change (−1.10 and −0.72), while the CAD/CAM additive (3D printing) groups showed the least color change (−0.48 and −0.54). Clinicians should choose appropriate denture cleansers for newly introduced denture base resins to minimize the changes in the color of the dentures.

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