RESUMO
PURPOSE: To introduce a novel design for scan body accessory parts that are reusable, easy to attach and detach without permanent change of the scan body, and can be used with different inter-implant distances to enhance the accuracy of complete arch implant scans. MATERIALS AND METHODS: A maxillary polymethylmethacrylate (PMMA) model with a soft tissue replica was fabricated with four implant analogs located at tooth positions 17, 13, 22, and 27 with 18, 25, and 30 mm inter-implant distances. Four scan bodies (SBs) were attached to the implants. The model was scanned with a laboratory scanner to be used as a reference scan. A total of 40 scans were made with the same intraoral scanner and they were divided equally into two groups. Group A: Complete arch implant scans without scan body accessories (n = 20), and Group B: Complete arch implant scans with scan body accessories (n = 20). Intraoral scans were exported and superimposed on the reference scan using reverse engineering inspection software to be evaluated for 3D deviations, angular deviations, and linear deviations. Statistical analysis was performed with student t-test and analysis of variance (ANOVA) with repeated measures followed by post hoc adjusted Bonferroni test. The level of significance was set at P = 0.05. RESULTS: The scan body accessories decreased both the 3D and linear deviations, with a statistically significant difference at SB4 for the 3D deviation (P = 0.043) and the linear inter-implant discrepancies between SB1-SB2 and SB3-SB4 (P = 0.029 and < 0.001), respectively. However, there was no statistically significant difference in angular deviation between the study groups. Implant positions had significant differences within each group. CONCLUSIONS: A significant improvement in the accuracy of the complete arch implant digital impression was achieved by using the scan body accessories, particularly in reducing the 3D and linear deviations at the most distant implant positions.
RESUMO
PURPOSE: Attempts have been made to decontaminate the implant surface by using diode lasers. However, the parameters that provide efficient decontamination without altering the topography or surface characteristics of titanium implants are still unclear. The aim of the present study was to evaluate the effect of altering the power of diode laser (940 nm) application on the hydrophilicity, surface topography, and chemical composition of sandblasted, large grit, acid-etched (SLA) treated titanium alloy implant surface. MATERIALS AND METHODS: Thirty-six SLA-treated titanium discs (Dentis Co., Ltd.) were used in this study. The hydrophilicity of all discs was measured by using a contact angle goniometer (190 CA; Rame-hart Co, Ltd). Discs were randomly divided into four groups (n = 9 each) based on the power of the diode laser used. Group I (control, no lasing group), group II: treated with 1 W power, group III: 2 W power, and group IV: 3 W power. The chemical composition of the SLA discs was evaluated by using energy dispersive x-ray spectroscopy (EDX) before laser application. Hydrophilicity was reevaluated after the application of laser irradiation. The surface topography of all discs was examined. Changes in the chemical composition of the titanium discs were investigated following the lasing procedure. Morphometric analysis of the surface area (µm2 ) of the indentations created following laser application was also evaluated. Data were collected and the Shapiro-Wilk test of normality was used. Comparisons between the four study groups were done by using the Kruskal-Wallis test, while that to evaluate the morphometric analysis of the surface area was done by using One-way ANOVA (P < 0.05). RESULTS: The average contact angle of the drop of distilled water to the SLA discs significantly decreased after laser treatment (P < 0.05). The largest contact angle was measured in the control group, followed by the 1 W group, and the 2 W group. The smallest angle was measured in the 3 W group. Considerable surface alterations such as melting and flattening were observed on examination of the surface topography of the 3 W group followed by the 2 W group. The least changes were observed in association with the 1 W group in comparison to the control group. The EDX analysis showed the appearance of peaks of the oxygen and carbon elements after the lasing procedure with the highest percentage in the 3 W group. The average of the surface area of the created indentations significantly increased with increasing the power of the diode laser used (P < 0.05). CONCLUSIONS: The application of diode laser (940 nm) with 2 W and 3 W powers significantly altered the hydrophilicity, the surface topography, and the chemical composition of titanium discs. Diode laser (940 nm) with 1 W power can be safely used on SLA titanium implant surfaces with no damaging effect on the surface topography or hydrophilicity.