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Article

Optimizing Post-Processing Parameters of 3D-Printed Resin for Surgical Guides

by
Maria Gabriela Packaeser
1,
Alexander Christiaan Santana
1,
Amanda Maria de Oliveira Dal Piva
2,
Cornelis Johannes Kleverlaan
2 and
João Paulo Mendes Tribst
1,*
1
Department of Reconstructive Oral Care, Academic Centre for Dentistry Amsterdam (ACTA), Universiteit van Amsterdam, and Vrije Universiteit Amsterdam, 1081 LA Amsterdam, North Holland, The Netherlands
2
Department of Dental Materials, Academic Centre for Dentistry Amsterdam (ACTA), Universiteit van Amsterdam, and Vrije Universiteit Amsterdam, 1081 LA Amsterdam, North Holland, The Netherlands
*
Author to whom correspondence should be addressed.
J. Compos. Sci. 2025, 9(10), 553; https://doi.org/10.3390/jcs9100553
Submission received: 5 September 2025 / Revised: 2 October 2025 / Accepted: 8 October 2025 / Published: 10 October 2025
(This article belongs to the Section Composites Manufacturing and Processing)
Browse Figures
Versions Notes

Abstract

This study evaluated post-processing protocols for 3D-printed implant surgical guides, aiming to determine the ideal timing after printing and post-curing durations that do not compromise residual monomer release and leachable components or mechanical properties. Specimens made of a surgical guide resin were 3D-printed (Formlabs Form 2) into bars (14 × 1 × 1 mm; n = 10) and square-shaped samples (10 × 10 × 1 mm; n = 1). They were grouped based on the time elapsed after printing (immediate, 24 h, and 72 h) and underwent washing in 99% isopropyl alcohol. Post-curing was performed for 5, 10, 20, or 30 min using a UV-light curing unit (NextDent LC-3DPrint Box). Residual monomer and components levels were assessed through solvent dissolution tests (n = 5), while mechanical properties were evaluated via flexural strength (n = 10) and hardness (n = 10). Statistical analysis with one-way ANOVA and Tukey’s post hoc test showed no significant differences in flexural strength across curing times or storage periods (p > 0.05), with values ranging from 42.93 MPa to 59.43 MPa. Monomers and leachable components were significantly higher immediately after printing (0.84 ± 0.36 mm3) compared to other groups (p < 0.05). For Vickers hardness, a 10 min curing protocol produced values comparable to longer durations (20.26 HV at 20 min/24 h), while the lowest hardness was 14.59 HV in the 5 min groups (p < 0.001). These findings suggest that delaying post-processing up to 72 h and reducing curing time to 10 min do not compromise mechanical properties, released monomers, and leachable components.

1. Introduction

In recent years, three-dimensional (3D) printing has advanced and created new ways to make applications across the health industry, which includes medicine, orthopedics, engineered tissue models, medical devices, and dentistry [1,2]. As an example, 3D printing is now used in dentistry to make temporary crowns, dental models, and full-arch implant guides [3,4]. With the rise of CAD-CAM technologies, 3D printing has the potential to optimize workflow and patient seating time [5]. 3D-printed dental devices can also exhibit improved trueness, defined as the closeness of measurement results to the true value, and precision, which refers to the repeatability or reproducibility of those measurements [6].
Implantology is a dental specialty that can significantly benefit from 3D printing technology [7,8]. Traditionally, surgical guides for dental implant placement are fabricated via a lab-side approach, involving dental technicians and necessitating multiple steps such as sending the guide to an external laboratory for production and subsequent delivery [9,10]. This workflow can be time-consuming and often requires an additional patient appointment before implant placement. In contrast, the chairside approach enables in-office fabrication of surgical guides using desktop 3D printing, reducing turnaround time and streamlining clinical workflow [9,11]. The digital workflow can help reduce the risk of errors in each manufacturing step [12], facilitate the try-in process, and improve communication between the patient, dentist, and technician [13]. 3D printing also plays a crucial role in digital workflow, allowing for the precise creation of surgical guides following the virtual planning in dedicated software [14,15]. By handling all steps of the process, dentists can enhance implant treatment outcomes [16]. Finally, using a guide gives a more accurate and predictable outcome than placing implants freehand [17].
Despite these advantages, the manufacturing of 3D-printed surgical guides remains critical, as post-processing parameters may significantly impact the quality of the surgical guide and, therefore, the accuracy of implant placement [4,18]. Errors can arise from overusing alcohol in the washing step and inadequate removal of uncured resin [19]. Incomplete post-curing leaves guides under-polymerized and mechanically weak, while optimized post-curing, especially under an inert nitrogen atmosphere, enhances hardness, monomer conversion, and dimensional stability by reducing oxygen inhibition [4]. Notably, Vara et al. found that nitrogen-assisted curing significantly improved the accuracy and surface properties of surgical guides [4]. Similarly, Alharbi et al. demonstrated that increasing the post-curing time from 20 to 40 min significantly enhanced the flexural strength and hardness of a printed resin, whereas extending to 60 min yielded no additional benefits and introduced variability, highlighting the importance of identifying optimal, not maximal, curing durations [20]. From a chemical safety perspective, the literature has reported the release of methacrylate monomers such as MMA, HEMA, and TEGDMA, with higher elution levels in organic solvents like methanol, but still within safe thresholds in vitro [21]. Research comparing the accuracy of single-implant surgical guides, focusing on an automated method (ultrasonic cleaning only) versus a combined approach of handwashing followed by ultrasonic cleaning, revealed that the manual approach yielded better accuracy, showing consistently higher discrepancy values than the automated method for surgical guides [18]. Finally, post-processing parameters, such as resin excess removal, washing and drying time, and adjusting the post-curing intensity, can be modified during the manufacturing process [22,23,24]. However, there is limited evidence available on modifying the curing time as well as the delay in removing the printed device from the print-building platform until it undergoes the post-processing steps. In a clinical setting, the immediate removal of printed surgical guides upon completion is often not feasible due to time constraints, workflow interruptions, or staff limitations. As a result, printed guides may remain on the build platform for extended periods before undergoing post-processing. This delay could potentially influence the mechanical and dimensional properties of the specimen before post-processing.
Current 3D-printed implant surgical guides require a 30 min post-processing period with a light-curing unit [25,26]. Given the critical nature of clinical time, this duration raises the question of whether post-processing can be shortened without compromising the quality of the surgical guide. Specifically, this study aims to investigate the effects of shorter curing time on the flexural strength, hardness, and residual monomer and soluble content of the guides. Additionally, it is often impractical for clinicians to immediately remove the printed device from the printer upon completion. Therefore, this study will also assess the impact of delayed post-processing steps on the properties. The null-hypothesis was that the mechanical properties of the 3D-printed resin would not vary significantly, considering the post-processing time.

2. Materials and Methods

2.1. Sample Preparation

The sample designs were created using Rhinoceros software (version 5.0 SR8, McNeel North America, Seattle, WA, USA). The samples included bars (14 × 1 × 1 mm; n = 10) and square-shaped specimens (10 × 10 × 1 mm; n = 1). These were fabricated via 3D-printing (Formlabs, Form 2, Somerville, MA, USA) using a light-cured surgical guide resin (Surgical Guide Resin V1, Formlabs, Somerville, MA, USA), as illustrated in Figure 1.
Printing parameters included a layer height of 50 μm and standard settings recommended by Formlabs. After printing, the specimens were washed in 99% isopropyl alcohol (IPA), followed by 3 min of agitation in IPA, and then rinsed in fresh IPA, according to the manufacturer’s protocol. Specimens were divided into groups based on the post-processing time after printing:
  • Immediately: specimens washed and cured immediately after printing.
  • 24 h: specimens stored in the 3D-print building platform, 24 h before post-processing.
  • 72 h: specimens stored in the 3D-print building platform, 72 h before post-processing.
Each group consisted of 64 specimens, including 60 bar-shaped and 4 square-shaped samples, except the solvent dissolution control group “immediate-immediate” (5 bar-shaped samples). After undergoing a washing protocol, the specimens were subjected to different light-curing durations in a light chamber (NextDent, LC-3DPrint Box, Soesterberg, The Netherlands): 5 min, 10 min, 20 min, and 30 min of post-light-curing.
Table 1 illustrates the study design according to the processing methods (processing time after printing and light-curing time) and the dependent variables measured: monomer release and leachable components based on weight and material density (n = 5), flexural strength in MPa (n = 10), and Vickers hardness (n = 1) for testing surgical guide material behavior (Figure 2). Hardness indentation was performed 10 times per sample, considering the test’s non-destructive nature.

2.2. Solvent Dissolution Test

For the baseline measurement, all bar-shaped specimens were weighed using an electronic scale (Mettler AT261 Deltarange, Greifensee, Switzerland). Following weighing, the specimens were placed in clean, inert containers and washed with acetone for 1 min to remove surface contaminants. Acetone was selected as the extraction solvent, appropriate for solubilizing low-molecular-weight chemicals of toxicological concern. Subsequently, the specimens were agitated in a mixer (Silamat Plus, Ivoclar, Schaan, Liechtenstein) at room temperature to ensure thorough contact with the solvent. After agitation, specimens were weighed again; the mass was recorded in grams (g). The volume (V) of each sample was calculated using the following formula:
V = g g / c m 3
where g is the weight obtained, and g/cm3 is the density of the Surgical Guide Resin, 1.9 g/cm3, provided by the manufacturer at green and post-cured stages. After the statistical analysis, the values were converted to mm3. The methodology was adapted from ISO-19993-12 [27,28,29].

2.3. Measuring Flexural Strength

Flexural strength was determined using a universal testing machine (Instron 6022; Instron, Norwood, MA, USA) according to a three-point bending test. The crosshead speed was set to 1 mm/min. Samples were positioned within a custom-designed ball-in-hole device (Figure 3).
The test specimen was placed in the device using a tweezer and supported by two internal, semi-circular support bases separated by a 10 mm span. A stainless-steel ball (10 mm in diameter) was then positioned, ensuring point contact with the center of the specimen, thereby applying the load. The setup was validated recently [30,31]. Flexural Strength (σ) in MPa was calculated using the following equation:
F S = 3 P L 2 b h 2
where P is the load in newtons, L is the test span in millimeters (mm), b is the specimen width in mm, and h is the specimen thickness in mm [32].

2.4. Measuring Hardness

Hardness was measured using a micro-hardness testing machine (HM-124, Mitutoyo Corp., Kanagawa, Japan). The surface of the printed square-shaped specimens was polished using #600-, #1200-, and #2400-grit SiC papers (CarbiMet SiC Abrasive Paper, Buehler, Lake Bluff, IL, USA) under constant water cooling. To simulate a defect, a Vickers indenter was used to create an indentation on the ground surface of each specimen. Ten indentations were performed in each sample, and a Vickers diamond was applied with a 19.6 N load in 15 s of dwell time.
H V = 0.1891 F d 2
where F is the test force in Newtons (N) and d is the average length of two diagonals of the indentation in millimeters (mm).

2.5. Statistical Analysis

All statistical analyses were performed using IBM SPSS Statistics version 30. Normality of the data was confirmed using the Shapiro–Wilk test. For each variable (solvent dissolution, flexural strength, and hardness), a one-way ANOVA was conducted to assess whether significant differences existed among the experimental groups. When a significant main effect was detected (p < 0.05), pairwise comparisons were performed using the Tukey post hoc test to identify specific group differences. Results were considered statistically significant at p < 0.05.

3. Results

3.1. Monomer Release and Leachable Components

One-way ANOVA revealed a significant effect of the experimental conditions (curing time and time after printing) on the volume difference (p < 0.001, Table 2), with a large effect size (η2 = 0.75, 95% CI [0.55, 0.77]). Table 3 presents the volume changes observed in the resin specimens before and after acetone immersion, serving as an indicator of non-reacted monomer content and soluble components. Post hoc Tukey analysis indicated that specimens measured immediately after printing (“Immediate/Immediate” group) exhibited a significantly greater volume difference (0.84 ± 0.36 mm3) compared to all other groups (p < 0.05). No other statistically significant differences in volume were observed between the remaining groups (Table 3).

3.2. Flexural Strength and Vickers Hardness

One-way ANOVA analysis (Table 4) revealed no statistically significant differences in flexural strength between the groups subjected to different light curing times and time after printing (p = 0.505), with a small effect size (η2 = 0.132, 95% CI [0.000, 0.332]).
In contrast to flexural strength, Vickers hardness was significantly affected by the experimental conditions (p < 0.001, Table 5), with a moderate to large effect size (η2 = 0.397, 95% CI [0.091, 0.574]). Capital letters indicate pairwise comparisons carried out by the Tukey post hoc test between groups. The flexural strength values ranged from 20.26 to 14.59. The highest mean Hardness is depicted as “A” for 10 min-24 h, 20 min-24 h, and 30 min-72 h groups. According to the Tukey post hoc test, the lowest mean is depicted as “E” for the 5 min-24 h and 5 min-72 h groups. B, C, and D overlap those groups. “A” and “E” are statistically different, as can be seen in Table 6. The results indicate that the time to initiate post-processing after printing does not produce statistically significant differences among the groups for the Vickers hardness test. However, specimens with 5 min of post-curing displayed significantly lower hardness compared to all other groups, as evidenced by the Tukey post hoc analysis, where the 5 min groups were labeled with the letter “E” (p < 0.05).

4. Discussion

The purpose of 3D-printing surgical guides is to achieve a stable guide that maintains its original dimensions, as planned in the CAD software, ensuring the most predictable outcome during implant surgery. This study aimed to evaluate variations in post-processing parameters for 3D-printed implant surgical guides and their effects. Currently, 3D-printed implant surgical guides undergo a 30-min post-processing step using a light-curing unit as recommended by the manufacturer. However, the demand for a faster workflow is not a new phenomenon: in clinical practice, 30 min is a considerable amount of time when factoring in chairside workflow efficiency, and reducing this duration not only speeds up patient care but also contributes to lower energy consumption, aligning with environmentally sustainable practices. One of the main reasons for the digital transition in dentistry is the ability to ensure standardized-quality manufacturing with reduced chair time [33,34]. Therefore, it is important to explore alternative post-processing methods that can reduce the time required without compromising the quality and accuracy of the surgical guides. According to the present findings, the null hypothesis was rejected, as the groups showed statistical differences for non-reacted monomers and Vickers hardness.
The present study has demonstrated that a 10 min post-curing duration of surgical guide resin yields physical characteristics comparable to those obtained with a 30 min post-curing process. Yeung et al. (2020) utilized the same surgical guide resin for 3D printing surgical guides, employing a post-curing protocol of one hour of light-polymerization followed by autoclave sterilization [14]. Their findings indicated that while varying implant systems exhibited some unique deviations, overall, the accuracy and precision of implant placement were within similar ranges and generally consistent when using in-office manufactured guides. This approach contrasts with the protocol recommended by Formlabs, which was adhered to by a recent study involving a 30 min post-curing process [35]. Burkhardt et al. (2022) found no malfunctions in the surgical guides, indicating that the suggested protocol from the manufacturer is acceptable [35]. Similar to this study, Kurzmann et al. (2017) and Whitley et al. (2017) implemented a 10 min post-curing protocol for surgical guide resin [9,36]. These findings may suggest that a 10 min post-curing duration may be sufficient for the post-curing of surgical guides. Another study did not evaluate varying light-curing times; however, it did evaluate curing in a nitrogen atmosphere, which improved polymerization completeness and mechanical properties, thereby enhancing the dimensional accuracy (trueness and precision) of the guides [4]. The nitrogen environment during post-curing was shown to reduce dimensional errors compared to curing in ambient air, regardless of washing technique or resin type [4].
The findings of this study indicated that the flexural strength values (MPa > 50) were comparable to those reported in the Formlabs datasheet [25,26]. Flexural strength is a critical factor in ensuring the accuracy of implant placement. However, bars do not replicate the exact shape and stress distribution of a full-arch surgical guide. Full-arch surgical guides may exhibit different stress points when positioned intra-orally. Additionally, a minimum wall thickness of 2 mm is recommended to maintain structural integrity and provide sufficient strength [26]. Future research evaluating the resin in actual full-arch surgical guides while adhering to the recommended wall thickness is essential to ensure both mechanical stability and clinical relevance. Furthermore, the hardness of the resin was assessed using Vickers Hardness, whereas the Formlabs datasheet reports hardness in Shore D. The findings revealed that all tested groups exhibited hardness values approximately half of those specified in the datasheet [26]. This discrepancy suggests that the surgical guide’s resin is softer than expected. Consequently, improper implant positioning due to material deformation should be considered when utilizing these guides, as their actual hardness may be lower than claimed.
When dental professionals receive 3D-printed surgical guides made from resins such as those from Formlabs from dental technicians or an in-house printer, they may assume that biocompatibility equates to absolute safety. Formlabs reports that their surgical guide resin is biocompatible, non-cytotoxic, non-sensitizing, and compliant with ISO 10993-1:2018 standards [26]. However, adverse reactions may still arise due to residual monomers or eluates, especially if polymerization is incomplete. Our study’s findings demonstrate that the volume of resin specimens significantly decreases after immersion in acetone, which serves as an indicator of unreacted monomers and soluble components. Specifically, specimens tested immediately after printing exhibited the greatest volume difference (0.84 ± 0.36 mm3), indicating a higher quantity of unreacted monomers, as well as polymerized polymers and catalysts that may also be dissolved. Over time, with post-curing and solvent interaction, these volume differences diminished, suggesting a potential reduction in residual monomers. Although previous research shows that unpolymerized methacrylic esters decrease over 72 h in vitro, the clinical relevance must consider the difference in exposure duration [35]. During actual implant procedures, surgical guides are typically in contact with tissues for 20 min on average, according to a randomized controlled clinical trial [37], which may minimize the risk of adverse reactions related to unreacted monomers. Nonetheless, our results suggest that a minimum post-curing time of at least 5 min is necessary to reduce the release of residual monomers and leachable components. However, further validation through appropriate biological safety tests, such as cytotoxicity, irritancy, and sensitization assessments, remains mandatory to fully establish biocompatibility. Furthermore, the observed volume change under solvent exposure suggests that insufficient curing may result in residual monomers capable of leaching during clinical use. Consequently, implementing proper post-curing protocols, such as optimized light exposure times in controlled curing chambers and/or the use of a nitrogen atmosphere, is essential to ensure accurate polymerization and enhance surface stability [4,20].
The results of this study indicated that the elapsed time between printing and the initiation of post-processing did not produce statistically significant effects. Consequently, starting post-processing immediately, after 24 h, or even after 72 h may be feasible under the conditions evaluated. This may suggest a potential degree of flexibility in scheduling post-processing procedures, such as printing on a Friday afternoon and completing washing and post-curing on the following Monday morning. However, additional research and comprehensive biological safety evaluations are necessary to ensure that such delays do not compromise the material’s safety, biocompatibility, or mechanical performance in clinical settings. Future studies should aim to validate the long-term stability and biological safety of the material when post-processing is postponed. Currently, no studies specifically evaluate the influence of post-processing timing in surgical guides, according to the authors’ knowledge. However, a previous study analyzed the dimensional stability of 3D-printed surgical guides stored under controlled conditions, with measurements taken immediately after post-processing and at multiple intervals up to 20 days [24]. The results revealed statistically significant but limited dimensional changes in critical features, such as the intaglio surfaces and sleeve housings [24]. These variations, although small, can impact fit and surgical accuracy, emphasizing the importance of considering timing and storage conditions after fabrication for enhanced clinical results [24]. Similarly, a recent report examined different surgical guide resins stored for up to 6 months, with assessments at 1 and 3 months [38]. They observed that storage in direct sunlight caused significant dimensional changes, recommending storage in dark environments to prevent instability [38].
Finally, it is important to acknowledge the limitations of this study, which include simplified specimen dimensions. The specimen bars used in this study were designed to fit the tensile tester and, therefore, were significantly smaller and had a different shape compared to actual surgical guides. Nonetheless, the flexural strength test results (Table 6) were comparable to those reported in the Formlabs data technical sheet [26]. Future research should explore multiple 3D-printing resins from various suppliers and incorporate biological testing to corroborate safety.

5. Conclusions

Despite the limitations of this in vitro study, the findings suggest that post-curing time can be reduced to 10 min without affecting the mechanical strength, hardness, or the monomers release and other leachable components of the 3D-printed surgical guide material. Furthermore, initiating post-processing within 0, 24, or 72 h after printing does not alter the overall properties of the surgical guide specimens, allowing flexibility in chair-side and lab-side workflows. However, these results are only valid for the specific resin tested, using a particular light-curing station with a non-inert gas atmosphere. Further biological validation is essential to confirm safety.

Author Contributions

Conceptualization, M.G.P., A.C.S., A.M.d.O.D.P., C.J.K. and J.P.M.T.; methodology, M.G.P., A.C.S., A.M.d.O.D.P. and J.P.M.T.; data curation, M.G.P., A.C.S. and J.P.M.T.; formal analysis, M.G.P., A.C.S. and C.J.K.; investigation, M.G.P., A.C.S. and C.J.K.; validation, M.G.P. and C.J.K.; visualization, M.G.P. and A.C.S.; writing—original draft preparation, M.G.P. and A.C.S.; writing—review and editing, M.G.P., A.C.S., A.M.d.O.D.P., C.J.K. and J.P.M.T.; supervision, A.M.d.O.D.P., C.J.K. and J.P.M.T.; funding acquisition, J.P.M.T.; project administration, J.P.M.T. All authors have read and agreed to the published version of the manuscript.

Funding

This research was funded by the University of Amsterdam, grant number #157 AUF Impact Call, Fall 2024.

Data Availability Statement

The original contributions presented in this study are included in the article. Further inquiries can be directed towards the corresponding author(s).

Acknowledgments

This research was made possible through an Impact Award from the University of Amsterdam Fund.

Conflicts of Interest

The authors declare no conflicts of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results.

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Jcs 09 00553 g001
Figure 1. 3D printing layout for fabricating sample designs using the PreForm software interface. It shows the arrangement of bars (14 × 1 × 1 mm) and square-shaped specimens (10 × 10 × 1 mm) on the build platform. The orientation and positioning optimize material usage and printing efficiency, while ensuring structural integrity for post-processing.
Figure 1. 3D printing layout for fabricating sample designs using the PreForm software interface. It shows the arrangement of bars (14 × 1 × 1 mm) and square-shaped specimens (10 × 10 × 1 mm) on the build platform. The orientation and positioning optimize material usage and printing efficiency, while ensuring structural integrity for post-processing.
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Figure 2. Illustrative representation of surgical guides.
Figure 2. Illustrative representation of surgical guides.
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Figure 3. Illustration of the flexural strength testing device: The external structure is shown on the left, while the internal testing setup is depicted on the right, where samples are positioned and assessed. In the internal setup, the following parameters are indicated: P represents the applied load, b is the width of the sample, h is the height of the sample, l denotes the span length between supports, and L indicates the total length of the sample.
Figure 3. Illustration of the flexural strength testing device: The external structure is shown on the left, while the internal testing setup is depicted on the right, where samples are positioned and assessed. In the internal setup, the following parameters are indicated: P represents the applied load, b is the width of the sample, h is the height of the sample, l denotes the span length between supports, and L indicates the total length of the sample.
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Table 1. Study experimental design and sample sizes for solvent dissolution, flexural strength, and hardness tests.
Table 1. Study experimental design and sample sizes for solvent dissolution, flexural strength, and hardness tests.
Time After PrintingCuring TimeSolvent DissolutionFlexural StrengthHardness
ImmediateImmediate5--
Immediate5 min post-light-cure5101
10 min post-light-cure5101
20 min post-light-cure5101
30 min post-light-cure5101
24 h5 min post-light-cure5101
10 min post-light-cure5101
20 min post-light-cure5101
30 min post-light-cure5101
72 h5 min post-light-cure5101
10 min post-light-cure5101
20 min post-light-cure5101
30 min post-light-cure5101
The “Immediate-Immediate” group was included to assess differences in solvent dissolution due to volume changes; therefore, flexural strength and hardness tests were not performed for this group.
Table 2. One-way ANOVA between the groups for volume difference.
Table 2. One-way ANOVA between the groups for volume difference.
Sum of SquaresdfMean SquareFSig.
Between Groups0.000140.00012.67<0.001
Within Groups0.000600.000
Total0.00074
Statistical significance was assessed at the 0.05 level.
Table 3. Volume before and after acetone, and volume differences (mm3) of Formlabs Surgical Guide Resin. Values were calculated based on measured weight (g) and the material density (1.19 g/cm3) at green and post-cured stages.
Table 3. Volume before and after acetone, and volume differences (mm3) of Formlabs Surgical Guide Resin. Values were calculated based on measured weight (g) and the material density (1.19 g/cm3) at green and post-cured stages.
Time After PrintingCuring TimeVolume Before
Mean (mm3) (SD)		Volume After
Mean (mm3) (SD)		Volume Difference
Mean (mm3) (SD)
ImmediateImmediate14.44 (0.15)13.60 (0.48)0.84 (0.36) B
5 min14.31 (0.21)14.07 (0.17)0.24 (0.08) A
10 min14.22 (0.08)14.11 (0.15)0.12 (0.11) A
20 min14.16 (0.07)14.09 (0.10)0.07 (0.06) A
30 min14.23 (0.11)14.12 (0.15)0.11 (0.07) A
24 hImmediate14.29 (0.14)14.05 (0.09)0.23 (0.09) A
5 min14.22 (0.09)14.14 (0.08)0.03 (0.09) A
10 min14.34 (0.14)14.28 (0.11)0.06 (0.04) A
20 min13.98 (1.24)13.82 (1.17)0.16 (0.13) A
30 min14.11 (0.07)14.02 (0.14)0.09 (0.08) A
72 hImmediate14.41 (0.20)14.02 (0.14)0.39 (0.12) A
5 min14.32 (0.06)14.13 (0.05)0.19 (0.03) A
10 min14.47 (0.08)14.32 (0.06)0.15 (0.04) A
20 min14.27 (0.22)14.15 (0.17)0.12 (0.08) A
30 min14.35 (0.10)14.25 (0.13)0.10 (0.12) A
Superscript letters indicate the results of Tukey’s post hoc pairwise comparisons between groups; different letters denote statistically significant differences at p < 0.05.
Table 4. One-way ANOVA between the groups for Flexural strength.
Table 4. One-way ANOVA between the groups for Flexural strength.
Sum of SquaresdfMean SquareFSig.
Between Groups4049.96511368.170.9400.505
Within Groups42,289.131108391.56
Total46,339.096119
Statistical significance was assessed at the 0.05 level.
Table 5. One-way ANOVA between the groups for Vickers Hardness.
Table 5. One-way ANOVA between the groups for Vickers Hardness.
Sum of SquaresdfMean SquareFSig.
Between Groups235.2101121.3813.918<0.001
Within Groups165.9291081.536
Total401.139119
Statistical significance was assessed at the 0.05 level.
Table 6. Mean and standard deviation (SD) of Vickers hardness (H) and flexural strength (MPa) results.
Table 6. Mean and standard deviation (SD) of Vickers hardness (H) and flexural strength (MPa) results.
Time After PrintingCuring TimeVickers Hardness (SD)Flexural Strength (SD)
Immediate5 min18.13 (2.93) BC59.43 (20.15) A
10 min17.29 (1.36) BCD42.93 (33.07) A
20 min16.58 (1.56) CD53.93 (16.15) A
30 min18.32 (1.47) BC50.83 (23.15) A
24 h5 min14.59 (1.42) E55.40 (8.48) A
10 min18.44 (0.35) AB54.08 (17.10) A
20 min20.26 (0.39) A41.68 (24.37) A
30 min17.39 (0.67) BCD54.59 (16.07) A
72 h5 min15.95 (0.33) DE45.99 (14.82) A
10 min17.66 (0.40) BCD44.25 (22.04) A
20 min18.38 (0.39) BC51.67 (13.01) A
30 min18.78 (0.40) AB42.07 (17.59) A
Superscript letters (A, B, C, D, E) denote the results of Tukey’s post hoc pairwise comparisons between groups. Groups sharing the same letter are not significantly different from each other (p ≥ 0.05), while groups with different letters are significantly different (p < 0.05).
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MDPI and ACS Style

Packaeser, M.G.; Santana, A.C.; Dal Piva, A.M.d.O.; Kleverlaan, C.J.; Tribst, J.P.M. Optimizing Post-Processing Parameters of 3D-Printed Resin for Surgical Guides. J. Compos. Sci. 2025, 9, 553. https://doi.org/10.3390/jcs9100553

AMA Style

Packaeser MG, Santana AC, Dal Piva AMdO, Kleverlaan CJ, Tribst JPM. Optimizing Post-Processing Parameters of 3D-Printed Resin for Surgical Guides. Journal of Composites Science. 2025; 9(10):553. https://doi.org/10.3390/jcs9100553

Chicago/Turabian Style

Packaeser, Maria Gabriela, Alexander Christiaan Santana, Amanda Maria de Oliveira Dal Piva, Cornelis Johannes Kleverlaan, and João Paulo Mendes Tribst. 2025. "Optimizing Post-Processing Parameters of 3D-Printed Resin for Surgical Guides" Journal of Composites Science 9, no. 10: 553. https://doi.org/10.3390/jcs9100553

APA Style

Packaeser, M. G., Santana, A. C., Dal Piva, A. M. d. O., Kleverlaan, C. J., & Tribst, J. P. M. (2025). Optimizing Post-Processing Parameters of 3D-Printed Resin for Surgical Guides. Journal of Composites Science, 9(10), 553. https://doi.org/10.3390/jcs9100553

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