Chemical analysis of the surface of dental implants after contact with surgical gloves / Análise química da superfície de implantes dentários após contato com luvas cirúrgicas

Objective: To perform a chemical analysis of the surface of dental implants after contact with surgical gloves by scanning electron microscopy and energy dispersive spectroscopy (EDS) and to correlate the findings with literature data. Materials and methods: Five commercially pure titanium implants submitted to surface treatment by acid attack and one pair of sterile latex gloves were selected. First, the implant and gloves were analyzed separately by EDS in order to observe the chemical elements on their surfaces. Next, the implant surface was put in contact with the surgical glove and analyzed by EDS to identify possible contaminants left by the latex glove. Results: Calcium, Zn, Mg, S, Si, and Nb were detected on the surface of the surgical glove, with Ca and Zn being the predominant elements in all samples. Titanium was detected on all implants; two implants only exhibited this element as described by the manufacturer and three contained small amounts of Ca, but Ti was the prevalent element. After contact of the implants with the surgical glove, elements that had not been detected on the gloves and implants during separate analysis, such as S, Zn, Si and Ca, were found. Conclusion: The present results and literature data permit us to conclude that the surface of titanium implants was contaminated after contact with surgical gloves and that inorganic chemical elements can modify the titanium oxide layer, resulting in possible interferences with the process of osseointegration

Effects of Image Compression o n L i n e a r M e a s u r e m e n t s o f Digital Panoramic Radiographs

This study aimed to evaluate the accuracy of panoramic radiographs obtained by digital system based on charge coupled device (CCD) and a phosphor storage plate (PSP) system with two different file formats, JPEG irreversible type and BMP. Linear measurements of artificial bony defects were made in dry mandibles with a digital caliper. Measures of digital panoramic radiographs were taken in ImageJ® software. Each measurement was performed twice by an experienced examiner. The intra-rater agreement was considered very strong (Pearson's correlation coefficient of 0.97). There was no significant difference between the linear measurements of dry mandibles, considered the gold standard, in relation to measurements obtained from digital radiographs (p=0.47). The error of these measures for the CCD was 1.04 mm (9.97%) for JPEG images and 1.03 mm (9.99%) for those with BMP format. For the PSP images, these values were 1.48 mm (14.94%) and 1.43 mm (14.43%), respectively. Although there was no statistical difference between the images with JPEG and BMP format, for both digital systems (p=1.00 for CCD and p=0.98 for PSP system), errors made on radiographs obtained by PSP system were significantly higher than those of CCD (p<0.05). The size of the files saved in JPEG was also significantly lower (p=0.005) compared with the files saved in BMP. It may be concluded that the digital radiographs, both saved in JPEG and BMP formats, are accurate, regardless the used digital system, and JPEG images are more suitable for teleradiology