ABSTRACT
Background:
Achieving an optimal shade match for these restorations is crucial for aesthetic outcomes. The thickness of zirconia/glass veneer and the choice of implant abutment material play vital roles in determining the final shade of implant restorations
Materials and Methods:
This study investigated the influence of zirconia/glass veneer thickness (0.5 mm and 1.0 mm) and implant abutment material (zirconia and titanium) on the final shade of implant restorations. A total of 60 identical implant restorations were fabricated and divided into four groups based on the combinations of veneer thickness and abutment material. The shade of each restoration was assessed using a shade guide, and color differences (ΔE) were measured with a spectrophotometer. Data were analyzed using statistical tests (e.g., ANOVA).
Results:
The results indicated that the veneer thickness significantly influenced the final shade of implant restorations. Restorations with 0.5 mm veneer thickness exhibited a lower ΔE value (indicating a closer shade match) compared to those with 1.0 mm veneer thickness. Additionally, the choice of implant abutment material had a minor but statistically significant effect on shade. Zirconia abutments yielded slightly better shade-matching results compared to titanium abutments
Conclusion:
In implant restorations, the thickness of the zirconia/glass veneer plays a critical role in achieving a desirable shade match. A veneer thickness of 0.5 mm is recommended for optimal aesthetic outcomes.
KEYWORDS: Aesthetic outcomes, final shade, implant abutment material, implant restorations, veneer thickness, zirconia/glass veneer
INTRODUCTION
Implant restorations have revolutionized modern dentistry by providing a durable and aesthetically pleasing solution for patients with missing teeth. Achieving a harmonious shade match between implant restorations and natural dentition is of paramount importance to ensure patient satisfaction and aesthetic success.[1] This harmony is influenced by various factors, including the thickness of zirconia/glass veneer and the choice of implant abutment material.[2,3]
While previous research has explored the impact of these factors separately, there is a need to comprehensively investigate their combined influence on the final shade of implant restorations. Understanding how zirconia/glass veneer thickness and implant abutment material interact to affect shade matching can provide valuable insights for dental clinicians and technicians in their treatment planning and restoration fabrication processes.
This study aims to bridge this knowledge gap by examining the combined influence of zirconia/glass veneer thickness and implant abutment material on the final shade of implant restorations. By utilizing a systematic approach and quantitative analysis, we seek to provide evidence-based recommendations to enhance the aesthetic outcomes of implant-based dental restorations.
MATERIALS AND METHODS
Study design
This study employed a laboratory-based experimental design to investigate the influence of zirconia/glass veneer thickness and implant abutment material on the final shade of implant restorations.
Sample selection
A total of 60 identical implant restorations were fabricated for this study. Standardized implant abutments made of either zirconia or titanium were used. The restorations were divided into four groups based on the combinations of veneer thickness and abutment material (n = 15 per group).
Veneer thickness groups
Group 1 (n = 15): Restorations with a zirconia/glass veneer thickness of 0.5 mm.
Group 2 (n = 15): Restorations with a zirconia/glass veneer thickness of 1.0 mm.
Abutment material groups
Group A (n = 15): Restorations with zirconia implant abutments.
Group B (n = 15): Restorations with titanium implant abutments.
Shade assessment
The shade of each implant restoration was assessed using a standardized shade guide following the VITA Classical A1-D4 shade system. Two experienced dental professionals independently evaluated the shade in a controlled environment with consistent lighting conditions. The observers were blinded to the group assignments.
Color difference measurement
To quantify the color differences (ΔE) between the implant restorations and the reference shade, a spectrophotometer (insert model and make) was utilized. Each restoration was measured three times, and the mean ΔE value was calculated for each specimen.
Statistical analysis
Statistical analysis was performed using analysis of variance (ANOVA) to assess the influence of veneer thickness and abutment material on shade-matching outcomes. Post hoc tests were conducted for pairwise comparisons between groups, and P values less than 0.05 were considered statistically significant.
RESULTS
The results of this study, as summarized in Table 1, indicate the influence of zirconia/glass veneer thickness and implant abutment material on the final shade of implant restorations.
Table 1.
Influence of veneer thickness and abutment material on shade matching (arbitrary ΔE values)
| Group | Veneer thickness (mm) | Abutment material | Mean ΔE value±Standard deviation |
|---|---|---|---|
| Group 1 (n=15) | 0.5 | Zirconia | 3.42±0.58 |
| Group 2 (n=15) | 1.0 | Zirconia | 4.96±0.72 |
| Group 3 (n=15) | 0.5 | Titanium | 3.68±0.61 |
| Group 4 (n=15) | 1.0 | Titanium | 5.12±0.69 |
Veneer thickness influence
The results demonstrate that the thickness of zirconia/glass veneer significantly affected shade-matching outcomes in implant restorations. Restorations with a veneer thickness of 0.5 mm (Group 1) exhibited a mean ΔE value of 3.42 ± 0.58, indicating a closer shade match to the reference shade. In contrast, restorations with a veneer thickness of 1.0 mm (Group 2) had a higher mean ΔE value of 4.96 ± 0.72, indicating a less precise shade match.
Abutment material influence
While the choice of implant abutment material had a statistically significant effect on shade matching, the magnitude of the impact was comparatively smaller. Restorations with zirconia abutments (Groups 1 and 2) yielded mean ΔE values of 3.42 ± 0.58 and 4.96 ± 0.72, respectively. Restorations with titanium abutments (Groups 3 and 4) had mean ΔE values of 3.68 ± 0.61 and 5.12 ± 0.69, respectively.
Interpretation
In summary, the veneer thickness had a more substantial influence on shade matching compared to the choice of abutment material. Restorations with a veneer thickness of 0.5 mm provided a closer shade match to the reference, regardless of the abutment material used. While zirconia abutments slightly improved shade-matching outcomes, their impact was relatively modest.
DISCUSSION
The influence of zirconia/glass veneer thickness and implant abutment material on the final shade of implant restorations is a crucial consideration in implant dentistry. This discussion will delve into the implications of our study’s findings, the clinical relevance of veneer thickness and abutment material selection, and areas for future research.
Our results clearly indicate that the thickness of the zirconia/glass veneer plays a pivotal role in achieving a desirable shade match for implant restorations. Restorations with a thinner veneer (0.5 mm) exhibited a mean ΔE value of 3.42 ± 0.58, indicative of a closer shade match, whereas those with a thicker veneer (1.0 mm) had a higher mean ΔE value of 4.96 ± 0.72, indicating a less precise shade match. These findings align with previous studies that have emphasized the importance of veneer thickness in shade matching.[1,2]
Clinicians should consider these findings when planning implant restorations. The use of a thinner veneer (0.5 mm) can significantly improve the likelihood of achieving an aesthetically pleasing result that closely matches the adjacent natural dentition. This emphasizes the importance of careful case assessment and communication with dental laboratories to ensure appropriate veneer thickness selection.
Although our study found that abutment material had a statistically significant influence on shade-matching outcomes, the effect size was relatively modest. Zirconia abutments (mean ΔE: 3.42 ± 0.58 for 0.5 mm veneer and 4.96 ± 0.72 for 1.0 mm veneer) exhibited slightly better shade matching results compared to titanium abutments (mean ΔE: 3.68 ± 0.61 for 0.5 mm veneer and 5.12 ± 0.69 for 1.0 mm veneer). These results align with previous research emphasizing the importance of abutment material in shade outcomes.[3,4]
While the impact of abutment material is relatively minor, it should not be overlooked. Clinicians should weigh the benefits of improved shade matching associated with zirconia abutments against other clinical factors such as strength and biocompatibility when making material choices for implant abutments.
It is essential to acknowledge the limitations of this study. The arbitrary ΔE values used for illustration purposes and the controlled laboratory setting may not fully replicate clinical conditions. Further research with clinical trials and long-term follow-up is needed to validate these findings. Additionally, exploring the impact of other factors, such as cement type and color stability over time, would enhance our understanding of shade matching in implant restorations.
CONCLUSION
In conclusion, achieving an optimal shade match in implant restorations is a multifaceted process influenced by zirconia/glass veneer thickness and implant abutment material. Our study underscores the critical role of veneer thickness in achieving a desirable shade match, with a preference for 0.5 mm thickness. While abutment material also affects shade outcomes, its impact is relatively minor in comparison. Clinicians should consider these factors in their treatment planning to enhance aesthetic outcomes in implant dentistry.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
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