No abstract available.
Lasers, Gas* ; Lasers, Solid-State*

Submerged implants require secondary surgical uncovering of implants after healing period of 3 - 6 months. In surgical methods, there are surgical scalpel, tissue punch, electro-surgical, and laser-used uncovering, and laser-used uncovering, and so forth. The objectives of this study are investigation and assessment of 1) thermal change in clinical application for uncovering of HA-coated implant and pure titanium implant irradiated by pulsed Nd-YAG. CO2, and Er-YAG laser. 2) surface change of cover screws after irradiation using laser energy. The temperature of apex & side wall of implants were recorded at 10sec, 20sec, 30sec after 30sec irradiation to implant healing screw; 1) pulsed Nd-YAG laser; 2W, 20pps, contact mode 2) CO2 laser; water-infused & non-water infused state, 2.5-3.5W, contibuous mode, noncontact mode 3) CO2 laser; non-water-infused state, 3W, superpulse, noncontact mode 4) Er-YAG laser; (1) non-water infused state, 10pps, 60mj, contact mode (2) water-infused state, 10pps, 60mj, 80mj, 101mj, contact mode According to the results of this study, pulsed Nd-YAG laser is not indicated because of increase thermal change and pitting of metal surface of implant cover screw. By contrast, CO2 laser & Er-YAG laser are presumed to indicate because of narrow range of thermal change & near abscence of thermal damage of metal surface. Dental laser is thought to be much helpful to surgical procedure when it is used as optimal power and time condition considering characteristics and indications of each laser. Further research is needed to verify that these techniques are safe and beneficial to implant success.
Lasers, Gas ; Lasers, Solid-State ; Titanium

Lasers have used safely to and in the resection of highly vascular tumors or arteriovenous malformation. As far as blood vessel coagulation, arteries up to 2mm in diameter and veins up to 3mm in diameter can be reliably sealed with the Nd-YAG laser, and lesser size of vessels can be coagulated with the CO2 laser. Another advantage of laser is to be a useful tool for small vessel repair or anastomosis without microsuture technique. The aim of this experiment was to investigate intensity and duration of exposure with the CO2 laser for vessel coagulation and repair. 36 rats weighing 200 to 250 gm, were used in this study. For vessel coagulation of extracranial arteries and veins, power density between 10 and 50 watts/cm2(W) was applied with handpiece, and for vessel repair or anastomosis 2 W was applied with micromanipulator. The results obtained were as follows : 1) The artery was perforated immediately over 10 W with 0.5 seconds of exposure of smaller focal beam. 2) The artery was constricted in its diameter in defocused beam with 30-40 W, and perforated with 50 W. 3) The lower limit of venous coagulation was 15 W, 0.5 sec. of exposure and 2 mm of focal beam diameter. 4) The lower limit or arterial coagulation was 10 W, 5 sec. of exposure, 4 mm of focal beam diameter, and exposure time was reduced to 3 sec. at 20 W. 5) The repair or anastomosis of artery was accomplished with 2 W, 0.05 sec. of exposure of 0.2 mm of focused beam by 6 times of delivery, and the delivery times could be successfully reduced to half under the overlying thin blood clot film on the anastomosis site of the artery. 6) In the histological examination, the entire layer of coagulated vessel wall on the laser delivered side disclosed marked constriction and destruction. On the anastomosis site, re-endothelialization began from 3 days, and completed by 2 weeks after operation.
Animals ; Arteries ; Arteriovenous Malformations ; Blood Vessels* ; Constriction ; Lasers, Gas* ; Lasers, Solid-State ; Rats ; Veins

BACKGROUND: Laser facial skin resurfacing has become a method of treatment for photoaging and pigmentary conditions. Although excellent results can be obtained by high-energy, pulsed carbon dioxide(CO2) laser, significant morbidity exists due to the considerable thermal damage to the skin. The Erbium: Yttrium Aluminum Garnet(Er: YAG) laser, with a wavelength of 2940 nm, is well absorbed in water. This leads to a very small zone of thermal necrosis, compared ta the CO2 laser. OBJECTIVE: The purpose of this study was to evaluate the results of the combined use of the char-free CO2 laser and the Er: YAG laser in the treatment of facial wrinkles. METHODS: Forty-six patients, aged between 30 and 68 years, with facial wrinkles, were evaulated. Two types of resurfacing laser systems were utilized in this study, a high-energy, short-pulsed CO2 laser and a Er: YAG 1aser. Wrinkle improvement was evaulated by the patients satisfaction, clinical improvement, and photographic analysis before and after the resurfacing procedure. RESULTS: Twenty-six of the 46 patients had greater than an 80% improvement, and 19 patients had a 60-80% improvement. Only one patient showed a 50% or less improvement. CONCLUSIONS: The combination of char-free CO2 laser and Er: YAG laser for facial wrinkles is a safe and effective modality for laser skin resurfacing.
Aluminum ; Carbon Dioxide* ; Carbon* ; Erbium* ; Humans ; Lasers, Gas* ; Lasers, Solid-State* ; Necrosis ; Skin ; Water ; Yttrium

The protection afforded against CO2 and KTP(potassium titanium phosphate) laser-induced combustion by six different types of tracheal tubes was evaluated. Some of them were wrapped with aluminum foil. They were compared before and after the application of human blood to their external surfaces. The difference of protective efficacy against laser between normal saline filled and air filled cuff was evaluated, too. The tracheal tubes tested were laser-resistant tubes such as Bivona Fome-Cuf (Group 1), Xomed Laser-shield 11 (Group 2) and Mallincrodt Laser Flex (Group 3) tubes. Aluminum foil wrapped Rusch red rubber (RR) (Group 4) and Mallincrodt reinforced Polyvinylchloride (PVC) (Group 5) tubes and unwrapped Baxter plain PVC (Group 6) tubes were also tested. CO2 loser set to 38W in continuous mode and KTP laser set to 15W were directed at the shaft of the tracheal tube under study, which had 5L/min. of oxygen flowing through it. The laser was actuated for 90 seconds or until combustion or melting occurred. Bivona tubes (Group 1) resulted in combustion in 5 tubes before and after blood application with CO2 laser, but unaffected before blood and resulted in combustion in 4 of 5 after blood application with KTP laser. Laser-shield 11 tubes (Group 2) offered good protection form both laser before and after application of blood except 1 case. At one case in Group 2, combustion occurred after blood application with CO2 laser. A combustion occured in 1 of 5 prior to application of blood and 5 of 5 after blood in Laser Flex tubes (Group 3) with CO2 laser, but occurred no tube with KTP laser. Wrapped RR (Group 4) and reinforced PVC tubes (Group 5) were unaffected by both laser, but application of blood to the foil wrapped tube shaft resulted in melting in 4 of 5 tubes. Unwrapped PVC tube (Group 6) resulted in immediate combustion in all tubes tested with both laser. Saline inflated cuffs were not perforated only in Group 2 and 3 in KTP laser and perforated immediately in other groups, but there was no combustion with saline in all groups. Air filled cuffs were all perforated in both laser, and combustion occurred. The presence of blood on the surface of metallic foil wrapped or special laser-resistant tracheal tubes may make laser-induced combustion more likely during airway surgery. However, the Laser-shield 11 and aluminum foil wrapped tracheal tube provided good protection from even when covered with blood. In addition, Mallincrodt stainless steel Laser-Flex tube provided good protection from KTP laser only. The saline filling cuffs served as a heat sink that will absorb the lasers energy, thus preventing combustion of cuffs.
Aluminum ; Freezing ; Hot Temperature ; Humans ; Lasers, Gas ; Lasers, Solid-State ; Oxygen ; Rubber ; Stainless Steel ; Titanium

Portwine stains(PWSs) are congenital vascular malformations, commonly found in the face, caused by progressively ectactic postcapillary venules of the superficial vascular plexus. They are reported to occur in 0.3% of newborn, and depending on the location and size, they may lead to psychosocial complications. Recently, with the advent of the lasers, ruby, dye, argon and CO2 lasers have been used for the treatment of PWSs. However, the results are variable and unpredictable. We present a case of congenital hemifacial PWS treating with dermabrasion and overgraft with very thin split-thickness skin rather than laser therapy. We achieved good result by using this method.
Argon ; Dermabrasion* ; Humans ; Infant, Newborn ; Laser Therapy ; Lasers, Gas ; Lasers, Solid-State ; Skin ; Vascular Malformations ; Venules

No abstract available.
Lasers, Solid-State*

No abstract available.
Lasers, Solid-State*

No abstract available.
Lasers, Solid-State* ; Papilloma*

No abstract available.
Lasers, Solid-State*