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Background Esthetic dental restorations have gained increasing popularity. The surface of restorations should be smooth enough to achieve maximum esthetics and prevent the adhesion of microorganisms and food particles. This study aimed to assess the surface roughness and color change of composite specimens following airflow usage. Methods In this in vitro, experimental study, 30 Tokuyama composite discs were fabricated and randomly divided into three groups (n = 10) for the use of airflow with calcium carbonate/bicarbonate powder and conventional polishing with FlexiDisc. The surface roughness of the specimens was measured by profilometry while the color change was assessed by measuring the L*, a* and b* color parameters using spectrophotometry before polishing (T1). The composite specimens were then polished for stain removal, and their surface roughness as well as color parameters were remeasured after polishing (T2). Paired t-test and Tukey’s test were applied for within-group and between-group comparisons. Results Significant differences were noted in roughness average (Ra) between airflow with calcium carbonate (0.251 ± 0.014 μm) and airflow with sodium bicarbonate (0.421 ± 0.208 μm), and between airflow with sodium bicarbonate and FlexiDisc (0.207 ± 0.076 μm) groups after polishing (P < 0.05). Regarding the correlation of change in surface roughness and color parameters at T1 and T2, an inverse correlation was noted between the change in surface roughness and all color parameters except for L*. In other words, reduction in surface roughness decreased the a* and b* color parameters. Conclusions Within the limitations of this study, the results showed that the airflow device used in this study had no significant difference with conventional polishing in terms of reduction in surface roughness and staining. Considering the cost and maintenance of the airflow device, it is not suggested as a suitable alternative to the conventional polishing procedures. Trial Registration Number: This study does not involve human subjects.

Background: Esthetic dental restorations have gained increasing popularity. The restoration surface should be smooth enough to prevent adhesion of microorganisms and food particles, and achieve maximum esthetics. This study aimed to assess the surface roughness and color change of composite specimens following the use of an airflow device. Methods: In this in vitro, experimental study, 30 Tokuyama composite discs were fabricated and randomly divided into three groups (n=10) for the use of airflow with calcium carbonate powder, airflow with sodium bicarbonate powder, and conventional polishing with FlexiDisc. The surface roughness of specimens was measured by profilometry while the color change was evaluated by measuring the L*, a* and b* color parameters by spectrophotometry before polishing (T1). The composite specimens were then polished for stain removal and their surface roughness and color parameters were measured again after polishing (T2). Paired t-test and Tukey’s test were applied for within-group and between-group comparisons.Results: Significant differences were noted in Ra (the roughness average pf surface) between airflow with calcium carbonate (0.251 ± 0.014 µm) and airflow with sodium bicarbonate (0.421 ± 0.208 µm), and also between airflow with sodium bicarbonate and FlexiDisc (0.207 ± 0.076 µm) groups after polishing (P<0.05). Regarding the correlation of change in surface roughness and color parameters at T1 and T2, an inverse correlation was noted between the change in surface roughness and all color parameters except for L*. In other words, increasing the surface roughness difference (surface smoothing), decreased the a* and b* color parameters. Conclusions: Within the limitations of this study, the results showed that the airflow device used in this study had no significant difference with the conventional polishing in terms of reduction in surface roughness and staining. Considering the cost and maintenance of the airflow device, it is not suggested as a suitable alternative to the conventional polishing procedures. Trial Registration Number: This is not a human subject research.

Background: Esthetic dental restorations have gained increasing popularity. The restoration surface should be smooth enough to prevent adhesion of microorganisms and food particles, and achieve maximum esthetics. This study aimed to assess the surface roughness and color change of composite specimens following the use of an airflow device. Methods: In this in vitro, experimental study, 30 Tokuyama composite discs were fabricated and randomly divided into three groups (n=10) for the use of airflow with calcium carbonate powder, airflow with sodium bicarbonate powder, and conventional polishing with FlexiDisc. The surface roughness of specimens was measured by profilometry while the color change was evaluated by measuring the L*, a* and b* color parameters by spectrophotometry before polishing (T1). The composite specimens were then polished for stain removal and their surface roughness and color parameters were measured again after polishing (T2). Paired t-test and Tukey’s test were applied for within-group and between-group comparisons.Results: Significant differences were noted in surface roughness (Ra) between airflow with calcium carbonate (0.251 ± 0.014 µm) and airflow with sodium bicarbonate (0.421 ± 0.208 µm), and also between airflow with sodium bicarbonate and FlexiDisc (0.207 ± 0.076 µm) groups after polishing (P<0.05). Regarding the correlation of change in surface roughness and color parameters at T1 and T2, an inverse correlation was noted between the change in surface roughness and all color parameters except for L*. In other words, increasing the surface roughness difference (surface smoothing), decreased the a* and b* color parameters. Conclusions: Within the limitations of this study, the results showed that the airflow device used in this study had no significant difference with the conventional polishing in terms of reduction in surface roughness and staining. Considering the cost and maintenance of the airflow device, it is not suggested as a suitable alternative to the conventional polishing procedures. Trial Registration Number: This is not a human subject research.

Purpose:To compare the corneal power measurements obtained using different topographic instruments after myopic photorefractive keratectomy (PRK).Methods:Patients with myopia who were candidates for corneal refractive surgery were sequentially included. Pre-PRK and six months post-PRK corneal powers were measured using Javal manual keratometer, Orbscan II, Galilei, Tomey TMS4, and EyeSys 2000 topographers. Measured values were compared with those obtained using the clinical history method (CHM).Results:This study included 66 eyes of 33 patients. The lowest keratometric measurements were obtained using the Galilei topographer (42.98 ± 1.69 diopters, D) and the highest measurements were obtained using the Javal manual keratometer (43.96 ± 1.54 D) preoperatively. The same order was observed postoperatively. Effective refractive power (EffRP) measured using EyeSys was most similar to the values obtained using CHM (ICC, intraclass correlation coefficient = 0.951), followed by the total corneal power measured using the Galilei system (ICC = 0.943). The values obtained using the adjusted EffRP formula (EffRP – 0.015*Δ Refraction – 0.05) were more consistent with the values obtained using CHM (ICC = 0.954) compared to those obtained with the adjusted average central corneal power formula measured using the Tomey system (ICC = 0.919).Conclusion:Post-PRK corneal powers measured using the adjusted EffRP formula were the most similar to values obtained using CHM.