RESUMO
BACKGROUND: When it comes to orthodontic diagnosis and treatment planning, the structures of the upper and lower airway space are crucial because of the role they play in craniofacial development. AIM: The major objective of this study was to evaluate the accuracy of lateral cephalogram in the evaluation of upper and lower pharyngeal space by comparing it to clinical usage of cone-beam computed tomography (CBCT) in quantifying the 3D morphology of the pharyngeal airway. METHODS AND MATERIALS: In total, 70 patients were included in the study. They had both a CBCT scan and a lateral cephalogram performed within a week of each other. Different cephalometric landmarks have been utilized to estimate linear and area dimensions for use in lateral cephalogram airway investigations. By superimposing the lateral cephalogram measurement of the vertical height of the pharyngeal airway over axial CBCT slices of 0.8 to 1 mm in thickness, airway volumes were calculated. For this study, we measured the pharyngeal airway space in each patient in two dimensions (2D) using the airway area from the lateral cephalogram and in three dimensions (3D) using the airway volume from the CBCT scan over the same region of interest, using a uniform scale and magnification throughout all split 3D volumes. RESULTS: The mean value of the area of pharyngeal space calculated by lateral cephalograph analysis (LCA) was 336.35 ± 86.49 mm2. The maximum value was 551.234 mm2. The minimum value was 206.32 mm2. The mean value of the volume of the same area calculated using CBCT was 3409.11 ± 1237.96 mm3. The maximum value was 5887.23 mm3. When the area calculated using LCA was compared with the volume calculated using CBCT, the correlation between them was significant statistically (r=0.831, p-value =0.000). The mean values of volume evaluated in 3D CBCT in males were 4198±1008 mm3 while for females it was 2980±1134.5 mm3. During the statistical analysis, these observations were found to have a positive correlation with increased volume of pharyngeal space in males as compared to that of females (p=0.006). The values of the area of pharyngeal space calculated using LCA in males was 370.1±60.9 mm2. while it was 301.9±88 mm2 in females. CONCLUSION: The area estimated for the pharyngeal airway on LCA correlates strongly with the volume determined by a CBCT scan. Since we have considered pharyngeal space analysis using CBCT to be a reliable and standard methodology, therefore a positive correlation of area calculated using LCA with volume calculated using CBCT shows that the analysis made by LCA can be reliable.
RESUMO
BACKGROUND: Surface roughness (SR) of dental components is significant because it impacts the surface area of the contact surface, which in turn affects corrosion behavior and biological compatibility. Orthodontic archwires (OA) with SR can affect the coefficient of friction, which in turn affects how effectively sliding biomechanics work and how the orthodontic appliance works efficiently. AIM: The objectives of the present investigation were to examine the SR of five distinct kinds of OA using an atomic force microscope (AFM) and to assess the merits of using AFM to analyze orthodontic materials. METHODS: For this investigation, there were five distinct orthodontic archwires with rectangular cross-sectional geometry. There were assigned different categories: Category 1: SmartArch wires (Ormco) (n=20), Category 2: Damon wires (Ormco) (n=20), Category 3: heat-activated nickel-titanium (HANT) wires (G&H Orthodontics) (n=20), Category 4: nickel-titanium (NiTi) wires (G&H Orthodontics) (n=20), Category 5: stainless steel (SS) wires (Ormco) (n=20). Each wire category's 20 samples were selected. Ten samples from each category had 5 mm of wire clipped from the finish point of the archwires. These were observed using the AFM in natural lighting. Using a cyanoacrylate glue that dries quickly, the samples were fastened to a metal holder. Ten randomly chosen patches of the surface, each measuring 15 × 15 µm, were taken from every sample and examined (N = 500). RESULTS: The mean values of roughness average (Ra) in category 1, category 2, category 3, category 4 and category 5 were 23.08 ± 17.66, 26.78 ± 5.65, 26.66 ± 3.89, 9.71 ± 0.29 and 11.29 ± 2.12 respectively. The values of Ra representing SR were greatest in category 3 (HANT wires) followed by category 2 (Damon wires) while values of SR were minimum in category 4 (NiTi wires) and category 5 (stainless steel wires). The findings had statistical significance also. CONCLUSION: The SR of stainless steel wire was discovered to be less than that of the other wires. The SR may have an impact on the efficiency of sliding mechanics as well as the appeal and corrosion resistance of orthodontic components.
