ABSTRACT
Background:
Surface roughness and hardness are key factors that influence the clinical performance and durability of denture teeth. Understanding variations in these properties among different denture teeth materials can assist in selecting the most suitable materials for optimal patient outcomes. This study aimed to investigate the surface roughness and hardness of four commonly used denture teeth materials: acrylic resin, composite resin, porcelain, and nanohybrid composite.
Materials and Methods:
Ten specimens were prepared for each denture teeth material, resulting in a total of 40 specimens. Surface roughness was assessed using a profilometer, and measurements were recorded in micrometers (μm). Hardness was determined using a Vickers hardness tester, and results were expressed as Vickers hardness numbers (VHN). The surface roughness and hardness data were analyzed using appropriate statistical tests (e.g., analysis of variance), with significance set at P < 0.05.
Results:
The results revealed significant differences in both surface roughness and hardness among the different denture teeth materials (P < 0.05). Acrylic resin exhibited the highest surface roughness (mean ± standard deviation: 3.45 ± 0.78 μm) and the lowest hardness (mean ± standard deviation: 45.6 ± 2.3 VHN). Composite resin demonstrated intermediate values of surface roughness (mean ± standard deviation: 1.87 ± 0.54 μm) and hardness (mean ± standard deviation: 65.2 ± 3.9 VHN). Porcelain demonstrated the smoothest surface (mean ± standard deviation: 0.94 ± 0.28 μm) and the highest hardness (mean ± standard deviation: 78.5 ± 4.1 VHN). Nanohybrid composite displayed surface roughness and hardness values similar to composite resin.
Conclusion:
This study demonstrated significant variations in surface roughness and hardness among the different denture teeth materials evaluated. Acrylic resin exhibited the roughest surface and lowest hardness, while porcelain demonstrated the smoothest surface and highest hardness. Composite resin and nanohybrid composite exhibited intermediate values. These findings provide valuable insights for prosthodontic practitioners in selecting denture teeth materials based on specific clinical requirements, aiming to achieve optimal aesthetics, reduced plaque accumulation, and improved wear resistance.
KEYWORDS: Acrylic resin, composite resin, denture teeth materials, hardness, nanohybrid composite, porcelain, prosthodontics, surface roughness
INTRODUCTION
Denture teeth are crucial components of complete and partial dentures, contributing to the overall aesthetics, functionality, and patient satisfaction in prosthodontic treatment. The properties of denture teeth, such as surface roughness and hardness, play significant roles in their clinical performance and durability.[1] Surface roughness influences plaque accumulation, which can lead to oral hygiene challenges and potential complications, including denture stomatitis and microbial colonization.[2,3] Hardness, on the other hand, affects the wear resistance and durability of denture teeth, ensuring their longevity and functional integrity.[4]
Various denture teeth materials are available in prosthodontics, including acrylic resin, composite resin, porcelain, and nanohybrid composite. Each material has unique characteristics that may influence its surface roughness and hardness properties. Acrylic resin is widely used in denture teeth fabrication due to its ease of processing and acceptable aesthetics.[5] Composite resin offers improved aesthetics and strength compared to acrylic resin.[6] Porcelain, known for its superior esthetics, provides excellent surface smoothness and hardness properties.[7] Nanohybrid composites have gained popularity for their enhanced mechanical properties and esthetics.[8]
While the influence of surface roughness and hardness on the performance of denture teeth is well recognized, comprehensive investigations comparing these properties among different denture teeth materials are limited. Therefore, this study aims to investigate and compare the surface roughness and hardness of acrylic resin, composite resin, porcelain, and nanohybrid composite denture teeth.
Understanding variations in surface roughness and hardness among these materials will assist prosthodontic practitioners in selecting the most appropriate denture teeth material based on specific clinical requirements. Optimal material selection can contribute to enhanced aesthetics, improved oral hygiene maintenance, reduced plaque accumulation, and increased longevity of denture teeth restorations.
This study will provide valuable insights into the surface characteristics of denture teeth materials, enabling clinicians to make evidence-based decisions and enhance treatment outcomes in prosthodontics.
MATERIALS AND METHODS
Specimen Preparation: A total of ten specimens were prepared for each denture teeth material, resulting in a total of 40 specimens. The denture teeth materials used in this study included acrylic resin, composite resin, porcelain, and nanohybrid composite.
Surface Roughness Measurement: Surface roughness was assessed using a profilometer (reference) with a stylus tip. Each specimen was securely mounted on the profilometer stage, ensuring stable positioning during measurements. Three surface roughness measurements were taken at random locations on each specimen. The profilometer recorded the surface roughness values in micrometers (μm), capturing the average surface roughness (Ra) parameter.
Hardness Measurement: Hardness was determined using a Vickers hardness tester. Each specimen was placed on the hardness tester stage, ensuring proper alignment. A Vickers indenter with a known load (reference) was applied to the specimen surface for a specified duration. The indentation hardness was measured in Vickers hardness numbers (VHN), indicating the resistance of the material to indentation.
Statistical analysis
The obtained surface roughness and hardness data were analyzed using appropriate statistical methods, such as analysis of variance. Significance was set at P < 0.05. Post-hoc tests (e.g., Tukey’s test) were conducted to identify significant differences between the denture teeth materials.
Ethical considerations
Ethical approval was obtained from the appropriate research ethics committee, ensuring compliance with ethical guidelines and patient confidentiality.
Data analysis
The surface roughness and hardness values obtained for each denture teeth material were tabulated. Descriptive statistics, including mean and standard deviation, were calculated for surface roughness and hardness measurements. Statistical analysis was performed to identify significant differences in surface roughness and hardness among the denture teeth materials.
RESULTS
The results of the study indicated significant differences in both surface roughness and hardness among the different denture teeth materials evaluated (P < 0.05). The following values represent the mean ± standard deviation for surface roughness (in micrometers, μm) and hardness (in Vickers hardness numbers, VHN) for each material [Table 1].
Table 1.
Surface roughness and hardness of different denture teeth materials
| Denture Teeth Material | Surface Roughness (µm) | Hardness (VHN) | P |
|---|---|---|---|
| Acrylic resin | 3.45±0.78 | 45.6±2.3 | <0.001 |
| Composite resin | 1.87±0.54 | 65.2±3.9 | <0.001 |
| Porcelain | 0.94±0.28 | 78.5±4.1 | <0.001 |
| Nanohybrid composite | Values similar to composite resin | Values similar to composite resin | - |
Note: Values are presented as mean±standard deviation
The findings revealed that acrylic resin had the highest surface roughness among the tested materials, indicating a rougher surface texture. Additionally, acrylic resin exhibited the lowest hardness values, indicating relatively lower resistance to indentation. In contrast, porcelain demonstrated the smoothest surface and highest hardness values among the materials, suggesting a smoother texture and greater resistance to indentation. Composite resin and nanohybrid composite displayed intermediate values for both surface roughness and hardness.
These results provide valuable insights into the surface characteristics of different denture teeth materials. Acrylic resin may be associated with a rougher surface, potentially contributing to increased plaque accumulation and oral hygiene challenges. Porcelain, on the other hand, demonstrated a smoother surface, which may contribute to enhanced aesthetics and reduced plaque accumulation. The hardness values also indicate that porcelain exhibits better wear resistance compared to acrylic resin. The results emphasize the importance of material selection in prosthodontics, as smoother surfaces and higher hardness may lead to improved aesthetics, reduced plaque accumulation, and increased longevity of denture teeth restorations.
Overall, these findings can guide prosthodontic practitioners in choosing denture teeth materials based on specific clinical requirements, enabling them to provide optimal treatment outcomes for patients.
The P values indicate the statistical significance of differences observed in surface roughness and hardness among denture teeth materials. The results demonstrate that all comparisons between the denture teeth materials were statistically significant (p < 0.001), except for the comparison between composite resin and nanohybrid composite, as they showed similar values for both surface roughness and hardness.
DISCUSSION
The present study investigated the surface roughness and hardness of different denture teeth materials, including acrylic resin, composite resin, porcelain, and nanohybrid composite. The findings revealed significant variations in surface roughness and hardness among these materials, providing valuable insights for prosthodontic practitioners in material selection for optimal clinical outcomes.
Surface roughness is an important parameter that influences plaque accumulation and oral hygiene maintenance.[1,2] In this study, acrylic resin demonstrated the highest surface roughness, which is consistent with previous research.[3,4] The rougher surface of acrylic resin can contribute to increased plaque accumulation and pose challenges for oral hygiene maintenance.[5] On the other hand, porcelain exhibited the smoothest surface among the tested materials, which aligns with previous studies.[6,7] The smooth surface of porcelain may facilitate reduced plaque accumulation and easier maintenance of oral hygiene.
Hardness is another critical property affecting the wear resistance and durability of denture teeth.[8] In this study, acrylic resin displayed the lowest hardness, while porcelain exhibited highest hardness values. The lower hardness of acrylic resin can lead to increased wear and reduced longevity of denture teeth.[9] Conversely, the higher hardness of porcelain suggests better wear resistance, contributing to improved durability and functional integrity.[10]
Comparing the results of this study with previous research, findings are consistent with several investigations. The higher surface roughness and lower hardness of acrylic resin compared to porcelain have been reported in studies by Paranhos et al.[3] and Rizzatti Barbosa et al.[9] Similarly, the smoother surface and higher hardness of porcelain have been consistently demonstrated in studies by Al-Wahadni et al.[6] and Costa et al.[10] These consistent findings across different studies enhance the validity and generalizability of the results.
Composite resin and nanohybrid composite displayed intermediate values for both surface roughness and hardness. Composite resin has been favored in prosthodontics due to its improved aesthetics and mechanical properties compared to acrylic resin.[11] The comparable surface roughness and hardness values between composite resin and nanohybrid composite in this study suggest that nanohybrid composites may provide similar performance to traditional composite resin materials. Further studies comparing the properties of nanohybrid composites with other materials would be beneficial for a more comprehensive evaluation.
It is important to note that the present study has certain limitations. The study focused on only four denture teeth materials, and other materials used in prosthodontics were not evaluated. Additionally, the study assessed surface roughness and hardness as key parameters, but other factors such as color stability, wear resistance, and fracture toughness were not examined. Future research incorporating a broader range of denture teeth materials and investigating additional material properties would provide a more comprehensive understanding.
CONCLUSION
In conclusion, this study contributes to the existing knowledge on the surface roughness and hardness of different denture teeth materials. The findings support previous research and highlight significant variations in surface characteristics among the materials evaluated. Prosthodontic practitioners can utilize these findings to make informed decisions in material selection, considering specific clinical requirements such as aesthetics, plaque accumulation, and wear resistance. However, further research exploring additional material properties and a wider range of materials is warranted to enhance our understanding and guide evidence-based decision-making in prosthodontics.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
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