Paulo Eduardo Miamoto Dias

Dry skull positioning device for extra-oral radiology and cone-beam CT

Extra-oral radiographs of dry skulls on scientific or forensic context have head position as a critical procedure. The aims of this article are to present a multi-purposed head-positioning device, and to describe the new method of image acquirement using the device to adequately keep the head in a correct and safe position during radiological or tomographic exam. The design was created from an average-sized skull and then tested in 20 others with different morphologies, sizes, weights, and structural state of preservation. A series of digital and analog orthopantomographies followed by a cone-beam computer tomography were obtained to assure that the correct positioning standards and anatomical visualization were achievable. The developed device properly kept adult skulls in position for all extra-oral radiographic exams, providing to operators a secure and facilitated way to achieve the proper position standards. The device did not impair the visualization of the anatomical structures neither on radiographs nor in cone-beam computer tomography.

Practical Application of Anatomy of the Oral Cavity in Forensic Facial Reconstruction.

The oral cavity’s importance in defining the facial region makes it a primary feature for forensic facial reconstruction (FFR). The aim of this study is to construct a pattern of reference for dimensions and proportions of the lips and establish parameters that may help estimate the vermilion borders’ height dimensions and the mouth’s width. By means of cone beam computed tomography, divided into two samples: sample 1 (n = 322; 137 male, 185 female) verified the linear distances delimited by anatomical landmarks in soft tissue. The sample 2 (n = 108; 40 male, 68 female), verified the proportions among the height of the vermilion borders, width of the mouth, and linear distances between craniometric landmarks in hard tissues, both from a Brazilian database. The measurements were completed using OsiriX, and the results were analyzed by means of descriptive statistics at a level of significance of 5%. The height of the vermilion borders corresponded to approximately 26% of the width of the mouth. The width of the mouth increased over the course of time in men and remained stable in women. In men, a mean intercanine distance of 75% of the total mouth’s width was found; for women, it was 80%. The parameters of the relations between soft and hard tissues in the oral cavity region presented that the distance between landmarks ID-SM (Infradentale-Supramentale) corresponded to 55% of the height of the vermilion borders of the mouth for both sexes, while the distance between landmarks PM-SD (Philtrum medium-Supradentale) corresponded to 85% in men and 88% in women. Mean values of 97% of the width of the mouth in women and 93% in men were attributed to the distance between the mentonian foramina. It was not possible to estimate the height of the labial vermilion borders by the bone measurements, FIs-Fli (Foramen incisivus superius-inferius) and NS-GN (Nasospinale-Gnathion). Profound knowledge of the anatomy and morphology of the oral cavity may contribute to increasing the precision of FFRs and help with human identification.

Exposure Standards for Digital and Analogue Dry Skull Orthopantomography

Forensic or scientific practices may require producing orthopantomography of dry skulls, that lack soft tissue, therefore modifications on the usual technique should be necessary. With the objective of standardizing the postmortem digital and analogue panoramic radiography this research produced a single a digital radiography and 13 analogue panoramic images, using different exposure configurations and four different objects to try to overcome the effects of the lack of soft tissue radiation absorption on the analog radiographs. A gel based ice pack, a 20 mm dental wax block, and a 0.5 mm metallic foil were placed in different points of the device. Also a previously exposed and developed film was placed inside the cassette between the unexposed film and the intensifying screen. The images were presented to 15 dentists of several specialties, who graded and ranked the images. In conclusion, the digital panoramic was easily obtained at a 60 kV and 2 mA settings and on analog equipments the use of two films inside the cassette achieved best results with 63 kV and 06 mA exposure settings.

Identification of a tooth-like foreign body in swine sausage.

A tooth‐like foreign body (FB) was found inside a sausage bread. Analysis aimed to investigate whether the FB was a tooth and its origin. The FB was measured, weighed, photographed, and radiographed. Macroscopic findings were suggestive of an anterior tooth. Histological slides of undecalcified cross‐sections of the FB and samples of human and swine teeth were prepared. Histological features of the FB (in light microscopy, 125× magnification) were discrepant from human tissues. Compared histological analysis displayed majority of features consistent with a hypsodont swine tooth, probably a canine. Cellularized cementum in crown region, adjacent to the enamel, and shape of the cementocytes were the main criteria excluding the possibility of human origin of the FB. Scanning electronic microscopy and energy‐dispersive spectroscopy were not performed because of fewer features to be analyzed and FB size. It was concluded that the FB may have been incorporated during meat grinding of the sausage.