Odovtos-International Journal of Dental Sciences (Odovtos-Int. J. Dent. Sc.), Online First, 2026. ISSN: 2215-3411

https://doi.org/10.15517/9pwfnk63

https://revistas.ucr.ac.cr/index.php/rOdontos

BASIC RESEARCH:

Chairside Light-Curing as a Feasible Alternative to Laboratory Polymerization for Indirect Composite Resins: A Performance-Based In Vitro Study

Fotopolimerización en sillón como alternativa viable a la polimerización en laboratorio para resinas compuestas indirectas: estudio in vitro basado en desempeño

Ammar Abdullah1 https://orcid.org/0009-0003-6648-7157

Nurhayaty Natsir1 https://orcid.org/0000-0003-0261-8296

Maria Tanumihardja1 https://orcid.org/0000-0003-1669-3609

1Department of Conservative Dentistry, Faculty of Dentistry, Hasanuddin University, Makassar, Indonesia.

Correspondence to: Prof. Nurhayaty Natsir, DDS, Ph.D, Specialist in Conservative Dentistry - nurhayatinatsir@unhas.ac.id

Received: 5-II-2026 Accepted: 7-III-2026

ABSTRACT: Indirect composite resins are widely used for extensive restorations due to their favorable mechanical properties; however, their polymerization typically requires laboratory light-curing devices, which may increase treatment time and cost and are not always readily available in routine clinical settings. High-intensity chairside light-curing units have been proposed as a potential alternative for extraoral polymerization. To evaluate, using a performance-based comparative approach under standardized post-curing conditions, whether chairside light-curing units can achieve mechanical properties comparable to those obtained with laboratory light curing in indirect composite resins. Indirect composite resin blocks (Twiny) were fabricated using a standardized mold (6×6×4 mm) and randomly allocated into three groups (n=20): laboratory light curing (control), chairside light curing for 20 s, and chairside light curing for 40 s. All specimens underwent thermal post-curing at 115 °C for 15 min to standardize polymer network maturation. Surface microhardness and compressive strength were evaluated. Data were analyzed using one-way ANOVA followed by the LSD post hoc test (p<0.05). Chairside light-curing groups demonstrated significantly higher surface microhardness values compared with the laboratory-curing group (p<0.05), with no significant difference between 20 s and 40 s exposures (p>0.05). Compressive strength values did not differ significantly among groups (p>0.05), indicating comparable bulk mechanical performance. Within the limitations of this in vitro study, chairside light curing achieved mechanical performance comparable to laboratory polymerization for indirect composite resins when combined with standardized thermal post-curing. These findings suggest that chairside light-curing may represent a clinically practical alternative for extraoral polymerization in settings where laboratory devices are unavailable, although long-term in vivo performance requires further investigation.

KEYWORDS: Indirect composite resin; Chairside light-curing; Laboratory light-curing; Polymerization efficiency; Post-curing heat treatment; Mechanical performance.

RESUMEN: Las resinas compuestas indirectas son ampliamente utilizadas para restauraciones extensas debido a sus favorables propiedades mecánicas; sin embargo, su polimerización generalmente requiere dispositivos de fotopolimerización de laboratorio. Las unidades de fotopolimerización de alta intensidad en sillón han sido propuestas como una alternativa potencial para la polimerización extraoral. El objetivo fue evaluar, mediante un enfoque comparativo basado en el desempeño bajo condiciones estandarizadas de post-curado, si las unidades de fotopolimerización en sillón pueden alcanzar propiedades mecánicas comparables a las obtenidas con la fotopolimerización de laboratorio en resinas compuestas indirectas. Se fabricaron bloques de resina compuesta indirecta (Twiny) utilizando un molde estandarizado (6×6×4 mm) y se asignaron aleatoriamente en tres grupos (n=20): fotopolimerización en laboratorio (control), fotopolimerización en sillón durante 20 s y fotopolimerización en sillón durante 40 s. Se evaluaron la microdureza superficial y la resistencia a la compresión. Los datos se analizaron mediante ANOVA de una vía seguido de la prueba post hoc LSD (p<0,05). Los grupos de fotopolimerización en sillón mostraron valores significativamente mayores de microdureza superficial en comparación con el grupo de fotopolimerización en laboratorio (p<0,05), sin diferencias significativas entre las exposiciones de 20 s y 40 s (p>0,05). Los valores de resistencia a la compresión no mostraron diferencias significativas entre los grupos (p>0,05), lo que indica un desempeño mecánico global comparable. Dentro de las limitaciones del estudio, se puede concluir que la fotopolimerización en sillón puede representar una alternativa clínicamente práctica para la polimerización extraoral en entornos donde no se dispone de dispositivos de laboratorio, aunque se requieren estudios in vivo a largo plazo para confirmar su desempeño.

PALABRAS CLAVE: Resina compuesta indirecta; Fotopolimerización en sillón; Fotopolimerización en laboratorio; Eficiencia de polimerización; Tratamiento térmico de post-curado; Desempeño mecánico.

INTRODUCTION

The restoration of extensive posterior cavities remains a clinical challenge in restorative dentistry due to the complex interplay between mechanical demands, material properties, and long-term functional stability of restorations (1). In stress-bearing areas, restorative materials are required to withstand occlusal loading while maintaining marginal integrity and resistance to wear over time. Consequently, the selection of appropriate restorative materials and polymerization protocols plays a critical role in the longevity and clinical success of posterior restorations (2).

Direct composite resin restorations are widely used because of their cost-effectiveness and reduced chairside time. However, in extensive cavities, direct composites may be associated with limitations such as polymerization shrinkage, marginal leakage, and decreased fracture resistance, which can compromise long-term clinical outcome (3,4). To address these limitations, indirect composite resin restorations have been developed, offering improved mechanical performance through higher filler loading, optimized resin matrices, and controlled extraoral polymerization (5).

Indirect composite resins are typically polymerized using laboratory-based light-curing devices that provide enclosed curing chambers, multidirectional light exposure, and controlled curing conditions (6). These systems have been reported to enhance polymer network formation and improve mechanical properties when combined with post-curing heat treatment (7). Despite their advantages, laboratory light-curing devices may increase treatment cost, require additional laboratory infrastructure, and may not be readily available in all clinical settings, particularly in resource-limited environments (6,8).

In recent years, advances in light-emitting diode (LED) technology have led to the widespread use of high-intensity chairside light-curing units in daily dental practice. These devices deliver focused irradiation with high output intensity and optimized spectral emission, enabling efficient intraoral polymerization of resin-based materials (7,9). Owing to their accessibility and ease of use, chairside light-curing units have been proposed as a potential alternative for extraoral polymerization of indirect composite resins (8). However, evidence regarding whether chairside curing can achieve mechanical performance comparable to laboratory light-curing for indirect restorations remains limited and inconclusive.

This research question is particularly pertinent in clinical environments where access to dedicated laboratory polymerization units may not be consistently available. The present study was conducted at the Faculty of Dentistry, Hasanuddin University, Makassar, Indonesia, where variability in laboratory infrastructure across treatment settings reinforces the practical importance of evaluating chairside alternatives.

Previous studies have largely focused on chemical characterization or degree of conversion of composite resins polymerized under different conditions, while fewer investigations have emphasized clinically relevant mechanical outcomes that directly reflect functional performance of indirect restorations. From a clinical perspective, properties such as surface hardness and compressive strength are essential indicators of a restorative material’s resistance to surface deformation, wear, and occlusal loading (10-12). Evaluating these parameters under standardized conditions provides practical insight into the feasibility of alternative polymerization strategies.

Furthermore, many previously reported investigations compared polymerization protocols without strictly controlling subsequent thermal post-curing parameters, thereby limiting the ability to isolate the independent contribution of irradiation geometry to final mechanical outcomes. In the context of indirect composite systems, where post-curing heat treatment is frequently employed to enhance polymer network maturation, failure to standardize this variable may obscure the true functional impact of the initial light-delivery configuration.

Therefore, the aim of this in vitro study was to evaluate, using a performance-based comparative approach, the mechanical properties of indirect composite resins polymerized with a chairside light-curing unit at different curing durations and compare them with those obtained using a laboratory light-curing device. The null hypothesis was that there would be no significant difference in microhardness and compressive strength between indirect composite resins polymerized using chairside and laboratory light-curing methods under standardized post-curing conditions.

Unlike previous investigations that have predominantly focused on spectroscopic analysis or degree of conversion measurements, the present study emphasizes clinically relevant mechanical outcomes under strictly standardized post-curing heat conditions. By equalizing thermal maturation across all experimental groups, this study was specifically designed to isolate the influence of irradiation geometry and curing modality on functional mechanical performance. By integrating controlled irradiation exposure with uniform post-curing heat treatment, the present study attempts to disentangle surface-dominant polymerization effects from bulk mechanical behavior, thereby providing a more clinically translatable assessment than studies limited solely to conversion metrics.

MATERIAL AND METHODS

Study Design

This study was conducted as an in vitro experimental laboratory investigation using a post-test control design. The experimental protocol was developed to evaluate the mechanical performance of indirect composite resins polymerized using different light-curing approaches under standardized conditions. All procedures were performed in accordance with institutional research policies, and the study protocol received ethical approval from the Health Research Ethics Committee of the Faculty of Dentistry, Hasanuddin University, Makassar, Indonesia (Approval No. 177/KEPK FKG-RSGM UH/EE/VI/2025).

All specimen fabrication procedures were carried out at the Conservative Dentistry Laboratory, Faculty of Dentistry, Hasanuddin University, whereas mechanical testing was performed at the Metallurgical Engineering Laboratory, Hasanuddin University.

Sample Size Calculation

The minimum sample size was initially estimated using the Federer formula for experimental laboratory designs, yielding a minimum of 10 specimens per group. Although the Federer calculation provided the minimum requirement for experimental validity, the number of specimens was increased to 20 per group to enhance statistical robustness, reduce the likelihood of Type II error, and improve reliability of between-group comparisons. This sample size is consistent with previously published laboratory studies evaluating microhardness and compressive strength of resin composites under different polymerization protocols.

Materials

The indirect composite resin used in this study was Twiny Indirect Composite (Yamakin, Japan), A3 dentin shade. Detailed information regarding the material composition, manufacturer specifications, and clinical indications is presented in Table 1. All light-curing devices employed in this study and their technical specifications are summarized in Table 2.

Table 1. Description of the indirect composite resin used in this study.

Material name	Manufacturer	Lot number	Composition	Manufacturer’s indications
Twiny Indirect Composite (Body Shade DA3)	Yamakin, Japan	1031128	UDMA, TEGDMA; approximately 56 vol% inorganic fillers (silica, alumina, zirconia; particle size < 15 µm)	Indicated for crowns, bridges, inlays, and onlays

Table 2. Specifications of the light-cure used in this study.

Light-curing device	Manufacturer	Light source	Wavelength range (nm)	Nominal irradiance (mW/cm²)
Smart Lite Pro	Dentsply, USA	Blue LED (4 units)	450–490	Approximately 1250
MICD a-cure	Shofu, Japan	Blue LED (36 units)	385–455	Approximately 1000

Specimen Preparation and

Random Allocation

A total of 60 composite resin specimens were fabricated using a standardized silicone mold measuring 6 mm×6mm×4mm. To ensure adequate polymerization throughout the specimen thickness, the composite resin was inserted incrementally in 2 mm layers. Each increment was polymerized according to the curing protocol assigned to the respective experimental group.

Following fabrication, specimens were randomly allocated into three experimental groups (n=20 per group) using simple randomization to minimize allocation bias.

Irradiance Verification and

Equipment Calibration

Prior to specimen fabrication, the irradiance output of both light-curing devices was verified using a calibrated dental radiometer to confirm consistency with manufacturer-reported specifications. Measurements were performed three times for each device, and the mean irradiance value was recorded. Verification was conducted prior to specimen preparation and repeated before each curing session to ensure stability of light output throughout the experimental period. The Vickers Hardness Tester and Universal Testing Machine were calibrated according to manufacturer specifications prior to mechanical testing to ensure measurement reliability and accuracy.

Environmental Control

All specimen preparation and mechanical testing procedures were conducted under controlled laboratory conditions at a temperature of 23±1°C and relative humidity of 50±5% to minimize environmental variability and ensure reproducibility.

Polymerization Protocols

Control Group (Laboratory Light-Curing)

Specimens assigned to the control group were polymerized using a laboratory light-curing unit (MICD a-cure, Shofu, Japan). Each 2 mm increment was exposed to light for 60 s at an approximate distance of ±50 mm from the light source. After removal from the mold, additional light curing was performed for 180 s in accordance with the manufacturer’s recommendations.

Chairside Light-Curing Groups

For the chairside light-curing groups, specimens were polymerized using a chairside LED light-curing unit (Smart Lite Pro, Dentsply, USA).

To standardize the curing surface and minimize the oxygen-inhibited layer, the composite resin surface was covered with a transparent matrix strip (0.05 mm thickness) and a glass slide (1 mm thickness). The curing tip was positioned directly on the matrix strip at a distance of 0 mm.

•Group P20: Light curing was performed for 20 s.

•Group P40: Light curing was performed for 40 s.

Post-Curing Heat Treatment

After light polymerization, all specimens were removed from the molds and stored in a sealed container. Subsequently, the specimens were subjected to a post-curing heat treatment using a dry heat sterilizer at 115°C for 15 min, following the manufacturer’s instructions for indirect composite resins.

The uniform application of thermal post-curing across all experimental groups was intended to standardize polymer network maturation and isolate the independent effect of the initial light-delivery configuration on final mechanical performance.

Methodological Rationale and Performance-Based Validation

This study was designed as a performance-based comparative investigation rather than a chemical characterization of polymerization kinetics. Mechanical properties, specifically surface microhardness and compressive strength, were selected as clinically relevant surrogate indicators of polymer network development and functional load-bearing capacity of indirect composite restorations.

Unlike investigations limited to spectroscopic degree-of-conversion analysis, the present study prioritizes functional mechanical outcomes that directly reflect material behavior under simulated clinical loading conditions.

To ensure methodological validity and comparability among groups, all specimens were fabricated with identical geometry, incremental thickness, irradiation positioning, and post-curing heat treatment. By maintaining strict standardization of these parameters, the experimental design focused on isolating the effect of polymerization approach while minimizing confounding variables. The deliberate equalization of post-curing thermal treatment was implemented to control secondary polymer network maturation effects, thereby allowing clearer assessment of the independent contribution of irradiation geometry and light-delivery configuration to mechanical outcomes. This methodological framework enables reliable comparison of chairside and laboratory light-curing strategies without reliance on additional analytical instrumentation.

Mechanical Testing

Microhardness Test

Surface microhardness was evaluated using a Vickers Hardness Tester (VHT). Three indentations were performed on the surface of each specimen using a load of 100 g with a dwell time of 20 s. Indentations were positioned at least 1 mm apart from each other and from specimen margins to prevent overlapping stress fields and ensure measurement independence. The mean Vickers hardness value obtained from the three indentations was calculated for each specimen and used for statistical analysis.

Compressive Strength Test

Compressive strength testing was performed using a Universal Testing Machine. Each specimen was subjected to a compressive load applied perpendicular to the surface at a crosshead speed of 0.5 mm/min until failure occurred. The applied load at fracture was recorded and converted to megapascals (MPa) based on the standardized cross-sectional area of each specimen, ensuring consistency in stress calculation across samples. The maximum load at failure was recorded, and compressive strength values were calculated accordingly.

Statistical Analysis

The data obtained from the microhardness and compressive strength tests were analyzed using one-way analysis of variance (ANOVA) to detect differences among experimental groups. Data normality was assessed using the Shapiro–Wilk test prior to ANOVA application. Post hoc comparisons were conducted using the least significant difference (LSD) test. The level of statistical significance was set at p<0.05. All statistical analyses were performed using standard statistical software.

RESULTS

The mean values and standard deviations of microhardness and compressive strength for all experimental groups are presented in Table 3.

Microhardness

The microhardness values of indirect composite resins polymerized using different light-curing approaches are illustrated in Figure 1. Specimens polymerized using the chairside light-curing unit for both 20 s (P20) and 40 s (P40) exhibited higher mean Vickers hardness values compared with those polymerized using laboratory light-curing (control group).

Statistical analysis revealed a significant difference in microhardness between the laboratory light-curing group and both chairside light-curing groups (p<0.05). No statistically significant difference in microhardness was observed between the P20 and P40 groups (p>0.05), indicating comparable surface hardness values for the two chairside curing durations.

Compressive Strength

The compressive strength values obtained for all experimental groups are summarized in Table 3. The mean compressive strength values were comparable across the laboratory and chairside light-curing groups.

Although the highest mean compressive strength was observed in the P40 group, followed by the control and P20 groups, one-way ANOVA demonstrated no statistically significant differences among the experimental groups (p>0.05), indicating similar bulk mechanical performance irrespective of the polymerization method and curing duration.

Table 3. Microhardness and compressive strength of indirect composite resins polymerized using different polymerization methods.

Group	Microhardness (VH)		Compressive strength (MPa)
	Mean	SD	Mean	SD
C (Laboratory light-curing)	33.13b	2.27	808.43	108.05
P20 (Chairside light-curing, 20 s)	36.16a	1.78	758.00	100.77
P40 (Chairside light-curing, 40 s)	36.55a	1.81	820.94	96.71

Values are presented as mean ± standard deviation.

Different superscript letters within the same column indicate statistically significant differences (one-way ANOVA followed by LSD test, p<0.05).

Figure 1. Mean Vickers microhardness values of indirect composite resins polymerized using different polymerization methods.

DISCUSSION

The present study evaluated whether chairside light-curing units could achieve mechanical performance comparable to laboratory light-curing for indirect composite resins using a performance-based comparative approach under standardized post-curing conditions. The findings demonstrated significantly higher surface microhardness values in specimens polymerized using chairside light-curing, whereas compressive strength values did not differ significantly among the evaluated polymerization strategies. By implementing standardized thermal post-curing across all experimental groups, the study design enabled focused interpretation of the influence of irradiation geometry on mechanical outcomes. This approach strengthens internal comparability by minimizing variability related to secondary polymer network maturation.

Microhardness is widely regarded as an indirect indicator of surface polymerization efficiency and resistance to surface deformation and wear (13). In the present study, specimens polymerized using the chairside light-curing unit exhibited higher microhardness values than those polymerized using the laboratory light-curing device (14). This finding may be attributed to the focused, high-intensity irradiation delivered by chairside curing units at minimal distance, which can enhance surface-level polymer network formation (5). Previous studies have reported that increased irradiance and reduced curing distance are associated with higher surface hardness in resin-based composites, supporting the present observations (15). Consistent with these reports, the present results suggest that direct-contact chairside irradiation may enhance superficial mechanical resistance relative to polymerization performed at greater light-source distances. Importantly, these surface differences were observed despite uniform post-curing heat treatment, indicating that initial light-delivery configuration can influence surface hardness even when subsequent thermal maturation is standardized.

Curing geometry represents an important determinant of energy delivery to resin-based materials. Chairside light-curing was performed with direct contact between the curing tip and the composite surface, whereas laboratory light-curing involved a greater distance between the light source and the specimen. As light intensity decreases with increasing distance, polymerization efficiency at the surface may be reduced when curing is performed farther from the material (16). Similar findings have been reported when resin composites are polymerized at increased distances from the light source, resulting in reduced surface hardness (17)( Figure 2).

Figure 2. Schematic illustration of the different polymerization approaches used for indirect composite resins, highlighting variations in light delivery geometry, irradiance distribution, and curing distance between laboratory and chairside light-curing methods.

Despite the differences observed in surface microhardness, no statistically significant differences in compressive strength were detected among groups. Compressive strength reflects the bulk mechanical behavior of the material under compressive loading (18). One possible explanation for the comparable compressive strength values is the standardized post-curing heat treatment applied to all groups. Thermal post-curing has been shown to enhance polymer chain mobility, promote additional monomer conversion, and reduce residual stresses in resin-based materials (19,20).

The absence of significant differences in compressive strength in the present study suggests that bulk mechanical performance may be influenced more substantially by overall curing energy combined with uniform thermal maturation than by variations in initial irradiation configuration alone. This interpretation should be considered inferential, as direct assessment of degree of conversion or cross-link density was not performed in the present investigation.

The observed dissociation between enhanced surface microhardness and comparable compressive strength underscores the distinction between surface-dominant polymerization effects and overall structural integrity. Clinically, this distinction is relevant because indirect restorations are exposed to both superficial wear and internal occlusal stresses. The present findings indicate that modification of irradiation geometry may primarily affect superficial mechanical characteristics, whereas standardized post-curing appears sufficient to maintain comparable bulk resistance under compressive load.

With respect to curing duration, extending chairside light-curing from 20 s to 40 s did not result in statistically significant improvements in either microhardness or compressive strength (21). This suggests that, under the irradiance conditions used in this study, 20 s exposure may deliver sufficient energy to achieve surface and bulk polymerization comparable to longer exposure durations (22). The absence of proportional mechanical gain with extended exposure is consistent with the concept of a polymerization saturation threshold, beyond which additional light exposure does not translate into measurable increases in mechanical properties (12,23).

Although laboratory light-curing systems remain the established standard for polymerizing indirect composite restorations, their availability may be limited in certain clinical settings. The present findings indicate that chairside light-curing, when combined with standardized thermal post-curing, can achieve mechanical performance comparable to laboratory curing with respect to compressive strength and superior surface microhardness under the conditions tested (24).

However, these findings should not be interpreted as evidence of long-term clinical equivalence. The present investigation was conducted under controlled in vitro conditions and did not incorporate thermocycling, cyclic fatigue loading, aging simulation, fracture toughness evaluation, or assessment of long-term intraoral degradation. Therefore, extrapolation of these results to clinical longevity should be undertaken cautiously, and further in vivo and aging studies are warranted.

Overall, within the experimental parameters of this study, chairside light-curing demonstrated mechanical performance that was not inferior to laboratory light-curing in terms of bulk compressive strength and yielded higher surface microhardness values under standardized post-curing conditions. These findings support the conditional feasibility of chairside polymerization as an alternative strategy in scenarios where laboratory curing systems are unavailable, while reaffirming that comprehensive long-term validation remains necessary.

STUDY LIMITATIONS

This study has several limitations that should be considered when interpreting the findings. First, the experiment was conducted under controlled laboratory conditions that do not fully reproduce the complex thermal, mechanical, and biological environment of the oral cavity. Aging-related factors such as thermocycling, cyclic loading, moisture fluctuations, and biochemical degradation were not simulated and may influence long-term clinical performance.

Second, the evaluation focused on surface microhardness and compressive strength as indicators of mechanical performance. Although these parameters are widely used as surrogate measures of polymerization efficiency and load-bearing capacity, direct characterization of polymerization kinetics was not performed. Third, only one indirect composite material and specific light-curing devices were tested. Differences in material composition, photoinitiator systems, and light-curing compatibility may produce different outcomes; therefore, extrapolation to other materials or polymerization systems should be made with caution. Despite these limitations, the standardized experimental design allowed a controlled comparison of chairside and laboratory polymerization approaches.

CLINICAL IMPLICATIONS

Despite these limitations, the present findings provide clinically relevant insights for restorative dental practice. Under standardized conditions and in combination with post-curing heat treatment, chairside light-curing units achieved mechanical performance comparable to laboratory light-curing in terms of compressive strength and demonstrated higher surface microhardness. These results suggest that chairside light-curing may represent a feasible alternative for extraoral polymerization of indirect composite restorations, particularly in settings where laboratory curing devices are not readily available.

However, these findings should be interpreted within the constraints of controlled laboratory conditions. The absence of long-term aging simulation, thermomechanical cycling, and fatigue assessment limits direct extrapolation to long-term intraoral performance. Clinically, the lack of significant differences between 20 s and 40 s chairside curing durations indicates that shorter curing times may be sufficient under the tested conditions. Nevertheless, clinicians should consider material characteristics, device compatibility, and manufacturer recommendations when selecting polymerization protocols, while laboratory light-curing systems remain the reference standard pending further long-term clinical validation.

CONCLUSION

Within the limitations of this in vitro study and under standardized post-curing conditions, chairside light-curing units produced higher surface microhardness values while maintaining compressive strength comparable to laboratory light-curing for the indirect composite resin evaluated. These findings indicate that chairside light-curing may represent a conditionally feasible alternative for extraoral polymerization of indirect composite restorations when laboratory curing devices are not readily available. However, these observations are limited to the mechanical parameters evaluated under controlled laboratory conditions, and further studies incorporating aging simulation and clinical validation are required to confirm long-term performance.

Conflicts of Interest: The authors declare that they have no conflict of interest.

Ethics: This study has received ethical approval from the Health Research Ethics Committee of the Faculty of Dentistry, Hasanuddin University, Makassar, with number 177/KEPK FKG-RSGM UH/EE/VI/2025.

Source of Funding: This study received funding LPDP scholarship from the Ministry of Finance of the Republic of Indonesia.

AUTHOR CONTRIBUTION STATEMENT: Conceptualization and design: A.A., N.N., and M.T.; Literature review: A.A.; Methodology and validation: A.A. and N.N.; Formal analysis: A.A.; Experimental study and data collection: A.A.; Data analysis and interpretation: A.A. and M.T.; Writing—original draft preparation: A.A.; Writing—review and editing: N.N. and M.T.; Supervision: N.N.. All authors read and approved the final manuscript.

AI Use Declaration: Artificial intelligence (AI) tools were used to assist in the creation of the conceptual schematic illustration presented in Figure 2. The figure was generated to visually represent the experimental polymerization approaches described in the Methods section. The authors reviewed and edited the final illustration to ensure its accuracy and consistency with the study design. No AI tools were used for data generation, data analysis, or interpretation of the study findings.

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