PURPOSE: The aim of this study was to evaluate the effect of Er:YAG laser on microstructure and roughness of TiO2 blasting implant surface. MATERIALS AND METHODS: Ten TiO2 blasting implant were used in this experiment. One implant was control group, and nine TiO2 blasting implant surfaces were irradiated with Er:YAG laser under 100 mJ/pulse, 140 mJ/pulse, and 180 mJ/pulse condition for 1 min, 1.5 min, and 2 min respectively. Optical interferometer and scanning electron microscopy was utilized to measure roughness and microstructure of specimens. RESULTS: The surface roughness was decreased after Er:YAG laser irradiation in all groups, but there was no significant difference. 100 mJ/pulse and 140 mJ/pulse group did not alter the TiO2 blasting implant surface in SEM study while 180 mJ/pulse group altered the TiO2 blasting implant surface. Implant surfaces showed melting, microfracture and smooth surface in 180 mJ/pulse group. CONCLUSION: Detoxification of implant surface using Er:YAG laser must be irradiated with proper energy output and irradiation time to prevent implant surface alteration.
Freezing ; Microscopy, Electron, Scanning

In electron therapy, low melting point alloy is used for shaping of the field. Electron field shaping material affect the output factor as well as the collimator system. The output factors of electron beams for shaped fields from NELAC-1018 were measured using ionization chamber of Farmer type in water phantom. The output factors of electron beams depend on the incident energy, inherent collimator system and the size of shaped field. Obtained results were followings. 1. In the smaller applicator, output varied extremely according to extent of collimator opening. 2. The higher energy, the output is less varied according to treatment field at small field.
Alloys ; Farmers ; Freezing ; Water

At the Hematology and Blood Transfusion Center Ho Chi Minh city. We have recently been performing collection, processing, and cryoprotection prior to freezing of cord blood for the first cord blood transplantation in Vietnam. The cord blood cells are sedimended by rouleaux formation using hydroxyethyl starch by gently centrifugation. The leukocyte-rich supematant is then transferred to a disposable processing bag set. The cells are then concentrated by a second centrifugation and removal of excess plasma supematant. The cryoprotection agent dimethyl sulfoxide is then slowly added to the concentrated cells, and the mixture transferred to a Themogenesis Corp, approved freezing bag for freezing and storage in the BioArchive System
Fetal Blood ; Freezing

Serially sectioned images (MR, CT, and anatomical images) of the whole body are helpful in anatomy education because three dimensional images can be reconstructed with the serially sectioned images, and then the three dimensional images can be sectioned and rotated. To make the most important anatomical images of the serially sectioned images, the cadaver's whole body should be embedded, frozen, and serially sectioned to make sectioned surfaces. In this study, to make the sectioned surfaces better than the Visible Human Project dataset, the equipments and techniques have been developed as follows. First, the equipments (embedding box, freezer) and techniques for embedding and freezing of the cadaver's whole body have been developed. Second, the equipments (cryomacrotome) and techniques for serial sectioning of the embedding box at 0.2 mm intervals have been developed. By using these equipments and techniques, the sectioned surfaces with good quality could be made at 0.2 mm intervals. The anatomical images made of the sectioned surfaces will be the basis for making better three dimensional images which are more helpful in anatomy education.
Dataset ; Education ; Freezing ; Humans

Keloids are benign cutaneous lesions that result from excessive collagen synthesis and deposition. Earlobe keloids are commonly seen as a complication of earlobe piercing and infection. Many different treatment modalities are available; however, therapeutic results are often unsatisfactory. Cryosurgery either used as monotherapy or in combination has been used successfully. However, keloids may require multiple sessions to achieve significant improvement and have a high rate of recurrence. Compared to conventional cryosurgery, intralesional cryosurgery has advantages of proper freezing of the deep layer of the lesion and a less harmful effect on the superficial layers. Herein, we present three cases of earlobe keloid effectively treated with intralesional cryosurgery.
Collagen ; Cryosurgery* ; Freezing ; Keloid* ; Recurrence

Absorbed DTP vaccines in the same Lot (produced by IVAC, Nha Trang) were kept at 4°C, -5 +/-10oC, -20°C on 2, 3 and 6 hours. After being thawed completely, the vaccine containers were vigorously shaken and the contents were examined for physical changes. The results showed that the containers kept at 4oC had no physical changes; the containers kept at -5 +/-10oC, 20°C for 6 hours had significant changes such as agglomeration, floccules or granular matter, and sedimented rapidly. It is suggested that structure of aluminum adjuvant in DTP vaccine is changed. The containers kept at -5 +/-10oC, -20°C for 6 hours can be considered as the positive control and the shaking test can be used to determine the previous freezing of adsorbed DTP vaccines.
Diphtheria-Tetanus-Pertussis Vaccine ; Freezing

No abstract available.
Animals ; Embryonic Structures* ; Freezing* ; Mice*

The restoration of extensive zygomatic complex defects is a surgical challenge owing to the difficulty of accurately restoring the normal anatomy, symmetry, proper facial projection and facial width. In the present study, an extensive post-traumatic zygomatic bone defect was reconstructed using a custom-made implant that was made with a selective laser melting (SLM) technique. The computer-designed implant had the proper geometry and fit perfectly into the defect without requiring any intraoperative adjustments. A one-year follow-up revealed a stable outcome with no complications.
Follow-Up Studies ; Freezing ; Titanium*

PURPOSE: The present study was performed to evaluate the effect of erbium:yttrium-aluminium-garnet (Er:YAG) laser irradiation on the change of hydroxyapatite (HA)-coated implant surface microstructure according to the laser energy and the application time. METHODS: The implant surface was irradiated by Er:YAG laser under combination condition using the laser energy of 100 mJ/pulse, 140 mJ/pulse and 180 mJ/pulse and application time of 1 minute, 1.5 minutes and 2 minutes. The specimens were examined by surface roughness evaluation and scanning electron microscopic observation. RESULTS: In scanning electron microscope, HA-coated implant surface was not altered by Er:YAG laser irradiation under experimental condition on 100 mJ/pulse, 1 minute. Local areas with surface melting and cracks were founded on 100 mJ/pulse, 1.5 minutes and 2 minutes. One hundred forty mJ/pulse and 180 mJ/pulse group had surface melting and peeling area of HA particles, which condition was more severe depending on the increase of application time. Under all experimental condition, the difference of surface roughness value on implant surface was not statistically significant. CONCLUSIONS: Er:YAG laser on HA-coated implant surface is recommended to be irradiated below 100 mJ/pulse, 1 minute for detoxification of implant surface without surface alteration.
Dental Implants ; Durapatite ; Electrons ; Freezing

This study was designed to investigate the stress distribution of alveolar bone in case of en masse retraction with lingual K-loop archwire using the 3-dimensional photoelastic stress analysis followed by stress freezing process. Lingual K-loop archwire which had loop in 15mm height was used and activated by retraction force of 350gm per each side. The results were as follows: 1. Central incisor: As the closer side to crown, the larger tensile stress was distributed at both mesial and labial surfaces and the larger compressive stress was distributed at distal surface. As the closer side to root apex, the larger compressive stress was distributed at lingual surface. The compressive stress was distributed at root apex. 2. Lateral incisor: The tensile stress was distributed at the coronal side of mesial surface. The compressive stress was distributed at distal surface. As the closer side to crown, the larger tensile stress was distributed at labial surface. The tensile stress was distributed at coronal side and the compressive stress was distributed at apical side of lingual surface. The compressive stress was distributed at root apex. 3. Canine: The tensile stress was distributed at coronal side and the compressive stress was distributed at apical side of mesial surface. The tensile stress was distributed at distal surface. As the closer side to crown, the larger tensile stress was distributed at both mesial and distal surfaces. The compressive stress was distributed at root apex. 4. Second premolar: The tensile stress was distributed at mesial surface. The compressive stress was distributed at coronal side and the tensile stress was distributed at apical side of distal surface. The compressive stress was distributed at coronal side of buccal surface. As the closer side to crown, the larger tensile stress was distributed at lingual surface. The compressive stress was distributed at root apex. 5. First molar: As the closer side to crown, the larger tensile stress was distributed at both mesial and distal surfaces. No stress was distributed at buccal surface and palatal root apex. As the closer side to crown, the larger tensile stress was distributed at both lingual surfaces. The compressive stress was distributed at buccal root apexes. 6. Second molar: The compressive stress was distributed at all root apexes. As the closer side to crown, the larger compressive stress was distributed at both mesial and lingual surfaces, and the larger tensile stress at both distal and buccal surfaces. Transverse bowing effect was observed in en-masse retraction with lingual K-loop archwire, however vertical bowing effect was not. Rather, reverse vertical bowing effect was developed.
Bicuspid ; Crowns ; Freezing ; Incisor ; Molar