No abstract

No abstract

No abstract

Aim:The aim of this in vitro study was to evaluate the band fit of metallic bandloop space maintainers fabricated by conventional and 3D printing technologies for clinical applications.Design: Sixteen digital intraoral impressions were selected, and resin models were printed with a 3D printer. Forty band-loop space maintainers were fabricated (20 each for both the conventional and digital groups). To evaluate the band fit of conventional and CAD/CAM-fabricated space maintainers, cement space was visualized with low-viscosity condensation silicone material on resin models. Digital evaluation was carried out using dual scan method by superimposing two scans of resin models covered with or without a silicone layer on the abutment tooth. The mean quadratic deviation (root mean square, RMS) was calculated. The RMS values between the groups were evaluated with Student's t test.Statistical significance was set at p < .05. Results:No statistical significance was found between the conventional and digital groups (p = .56). Conclusions:Within the limitations of this study, the band fit of conventional and CAD/CAM-fabricated space maintainers had no difference. Future research into CAD/CAM-fabricated appliances from different perspectives such as fracture strength and patient comfort is warranted.

Objective: To evaluate the trabecular internal structure of the mandibular condyle with fractal analysis on panoramic radiography in children. Study Design: 159 panoramic radiographs were separated into 8 groups according to age and gender. The radiographs were standardized as 8-bit images. Regions of interest, located on both mandibular condyles, were selected as 64x64 pixel squares. Image J v1.50i software was used to obtain the fractal dimension (FD) values by the box-counting method. Results: The data obtained from the right and left condyles were analyzed in terms of gender and age groups. No statistically significant difference was observed between the genders in respect of the mean FD values for both condyles (p&gt;0.05). Mean, standard deviations and the 95% confidence intervals for the FD values of the left and right condyles were obtained according to age. A statistically significant difference was observed in the mean FD values for both left (p= 0.019) and right (p= 0.000) condyles when all groups were compared and no statistically significant difference was found between all groups except the 6-year-old group for both condyles. In both condyles, the significantly lowest mean FD values were determined in the 6 years age group. Conclusions: The FD values of the mandibular condyle trabecular structure changed with age. It will be possible to evaluate these changes from panoramic radiographs by making calculations using the fractal analysis method.