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In this work the performances of three different techniques for 3D scanning have been investigated. In particular two commercial tools (smartphone camera and iPad Pro LiDAR) and a structured light scanner (Go!SCAN 50) have been used for the analysis. First of all, two different subjects have been scanned with the three different techniques and the obtained 3D model were analysed in order to evaluate the respective reconstruction accuracy. A case study involving a child was then considered, with the main aim of providing useful information on performances of scanning techniques for clinical applications, where boundary conditions are often challenging (i.e., non-collaborative patient). Finally, a full procedure for the 3D reconstruction of a human shape is proposed, in order to setup a helpful workflow for clinical applications.

Objective: To compare the mechanical and biological features of a polymethylmethacrylate (PMMA) disc for CAD/CAM prostheses (test samples, TG) with a traditional resin (control samples, CG). Methods: Mechanical analysis was performed using Dynamic Mechanical Analysis (DMA) and Brillouin's micro-spectroscopy. Human keratinocyte morphology and adhesion were analyzed by scanning electronic microscopy (SEM), cytotoxicity by the MTT assay, apoptosis by flow cytometry and p53, p21 and bcl2 gene expression by real time PCR. Results: TG exhibited a higher elastic modulus than CG (range 5100-5500 ± 114.3 MPa vs 3000-3300 ± 99.97 MPa). The Brillouin frequency was found at ?= (15.50 ± 0.05) GHz for TG and at ? = (15.50 ± 0.05) GHz and ? = (15.0 ± 0.1) GHz for CG where two peaks were always present independently of the sample point. SEM analysis revealed that keratinocytes on TG disks appeared to be flattened with lamellipodia. Keratinocytes on CG disks rose above the substrate with cytoplasmatic filaments. MTT viability data at 3 h and 24 h showed TG was significantly less cytotoxic than CG (p < 0.001). No significant differences emerged in apoptosis on CG and TG. Real-time PCR showed p53 expression increased after 3 h by about 9-fold in keratinocytes on TG (p < 0.001) and about 5-fold in those on CG (p < 0.001). High p53 expression persisted after 24 h on both disks. No significant variations were observed in p21 and bcl2 expression at any time-point. Significance: PMMA resins, as used in CAD/CAM technology, displayed suitable biocompatible and mechanical properties for removable prostheses.

In this paper is described the starting of a research activity to define measurement tecniques and instruments for analyzing the shape of an olive tree in order to obtain the most interesting geometric characteristics, such as stem diameter, branch direction and crown volume. After an introduction to possible non-contact measurement systems applied till now to trees, we have choose two of them: one based on laser scanner and the other based on structured light. Both as been used to performed measurements on a test case: an olive tree. Data processing and comparision is illustrated.