ABSTRACT
The in vivo tissue ablation characteristics of a pulsed infrared laser (Hol:YAG, lambda = 2120 nm) and a pulsed excimer laser (XeCl, lambda = 308 nm) were studied in an animal model. Laser energy was delivered via nylon fibers for the Hol:YAG laser and via quartz fibers for the excimer laser. Laser incisions were made under precise reproducible conditions on the sublingual side of the tongue and the gingiva of white rats. Laser surgery was done at two different energy output settings for the Hol:YAG laser and at one setting for the excimer laser. Histologic studies revealed tissue defects with clean contours for both laser types with small zones of necrosis of the adjacent tissue (Hol:YAG: 180 microns to 640 microns; excimer: 40 microns to 160 microns) and without carbonization. Both laser types function on the principal of photoablation and permit excellent control of tissue ablation. Wound healing was studied over a 10-day period and showed complete wound closure by re-epithelialization. The in vivo tissue ablation characteristics and the surgical reliability of the two lasers are compared and discussed with respect to oral and periodontal surgery.
Subject(s)
Laser Therapy/instrumentation , Lasers , Surgery, Oral/instrumentation , Animals , Gingiva/surgery , Male , Rats , Tongue/surgeryABSTRACT
The in-vivo bone ablation characteristics of a pulsed solid-state erbium:YAG laser were compared to those of a pulsed solid-state holmium:YAG laser. Partial osteotomies in the maxillary, the mandibulary, and the nasal bones of white rats were performed. The tissue response was examined by light microscopy. Thermal gradients following the laser application were also measured. Over all energy levels tested the erbium:YAG laser produced ablation of bone with minimal thermal damage to the adjacent tissue. The results of this study are promising for future application of the infrared holmium- and erbium:YAG lasers in otorhinolaryngology.
Subject(s)
Laser Therapy/instrumentation , Osteotomy/instrumentation , Animals , Body Temperature Regulation/physiology , Equipment Design , Male , Mandible/pathology , Mandible/surgery , Maxilla/pathology , Maxilla/surgery , Nasal Bone/pathology , Nasal Bone/surgery , RatsABSTRACT
In 15 patients suffering from maxillofacial cancer with radiochemotherapy-induced oral mucositis the local application of prostaglandin E2 (PGE2) tablets, 0.5 mg four times a day at a 4-h interval was performed. Plasma determination of the bicyclo-prostaglandin E2 metabolite showed no significant amount of the locally applied substance in the circulation. It is claimed that for this particular indication, PGE2 is a potent locally acting compound without affecting circulating levels.
