Optimization of Process Conditions for Additive Manufacturing Technology Combining High-Power Diode Laser and Hot Wire

A high-efficiency additive manufacturing technology that combines a high-power diode laser with a large-rectangle spot (beam width of 11 mm) and a hot-wire system was developed. The hot-wire system can generate Jo ule heat by wire current and heat a filler to its melting point independently from the main heat source of a high-power diode laser. A simple calculation method to derive the appropriate hot-wire current of Z3321-YS308L was proposed with verification by hot-wire feeding experiments without laser irradiation at various wire currents. The effect of process parameters, such as laser power, process speed, and the wire feeding rate (wire feeding speed/process speed) on bead characteristics was investigated by cross-sectional evaluations on three-layer depositions. High-speed imaging observations of wire melting and molten pool formation showed that the energy density input and the wire feeding rate were dominant parameters in terms of bead formation and hot-wire feeding stability. A 50-mm-high, 8-mm-wide, and 250-mm-long sample was fabricated by using appropriate process conditions, and tensile tests were performed by using a sub-sample from the large sample.

Effect of high-power diode laser on radical surfaces exposed as dental tubules obliteration: in vitro study

The aim of this study was to find adequate parameters of high-power diode laser for obliteration of dental tubules. Newly extracted human teeth (molars) were used for the research that were treated with high-power diode laser and then evaluated by scanning electron microscopy. Roots of 10 healthy teeth were used and prepared in 40 dentin blocks and dividing them into 4 groups: Control Group; G1, G2, G3 (groups treated with high-power diode laser), varying power, energy and application time. The images were evaluated randomly by 2 blinded, calibrated examiners who attributed scores to each image with a level of significance of 5%. The null hypothesis there was no difference between the groups tested regarding of the obliteration of the dentinal tubules. Considering the scores used for analyzing the SEM images, statistically significant differences were observed between the control and all the experimental groups (p < 0,05). However, the irradiated (experimental) groups showed no statistically significant differences between them, because at all the tested parameters the dentin tubules were shown to be obliterated (p < 0.05). The efficacy can be completed in the obliteration of tubules and interruption of fluid movement within the dentin tubules with treatment of the exposed surface with the high-power diode laser; however, the parameters of power and energy lowest showed better results.

Guided Periodontal Surgery: Digital Workflow for Correction of a Gingival Smile

To promote an effective and predictable treatment planning in cases of gingival smile correction, a periodontal surgical guided from virtual planning could be used. The guide was designed using planning software, based on the patient’s facial aesthetic analysis, photos and intraoral scanning. As a result, the surgical procedure by digital planning provided a more predictable, personalized and safe treatment and outcome to the patient. The present case report describes a gingival smile correction, using digital planning combined with high-power diode laser for periodontal surgery. After 3 months of preservation, there was less exposure of the gingiva in the smile and a high level of patient aesthetic satisfaction. Considering the importance of the correct treatment planning, it may be concluded that use of surgical guided made from a digital planning provided a predictable, personalized and safe treatment to the patient.