OBJECTIVETo investigate the effects of using guided bone regeneration (GBR) technique with an bioresorbable collagen membrane for repairing bone defects around dental implants.

METHODSIn 12 mongrel dogs, pure titanium implants were immediately implanted in mandibles after extraction of the mandibular third and fourth premolars of both sides, in which standard bone defects of 3 mm x 3 mm x 5 mm were created at mesial side of the implants. The defects on right side were covered with Co membrane, the left side was uncovered as control. The dogs were sacrificed 1, 2, 4, 6 months postoperatively. The specimens were removed and studied by gross observation, X-ray radiograph, histological examination, scanning electron microscope (SEM) and pull-out test.

RESULTSThe quantity and quality of new bone formation in experimental side which bone defects covered with Co membrane were much better than that in the control side.

CONCLUSIONWith the biodegradable property and excellent biocompatibility, Co membrane can be used for guided bone regeneration to promote the bone repair progress, and the promotion acts mainly at early stage of bone healing.

Animals ; Bone Regeneration ; Collagen ; Dental Implantation, Endosseous ; Dental Implants ; Dogs ; Guided Tissue Regeneration, Periodontal ; Mandible ; Membranes, Artificial ; Titanium

OBJECTIVE: We wanted to report on our experience with modified radiology-guided percutaneous gastrostomy (MRPG) without endoscopic or nasogastric access for treating patients with complete obstruction of the upper digestive tract. MATERIALS AND METHODS: Fourteen oncology patients (13 had hypopharyngeal cancer and 1 had upper esophageal cancer) with complete obstruction of the upper digestive tract were recruited. Conventional percutaneous endoscopic gastrostomy (PEG) and radiologic (fluoroscopy-guided) percutaneous gastrostomy (RPG) were not feasible in all the patients. An MRPG technique (with a combination of ultrasound, an air enema and fluoroscopic guidance) was performed in these patients. RESULTS: We achieved successfully percutaneous gastrostomy using the modified technique in all patients without any major or minor complications after the procedure. CONCLUSION: A modified radiology-guided percutaneous gastrostomy technique can be safely performed in patients who failed to receive conventional PEG or RPG due to the absence of nasogastric access in the completely obstructed upper digestive tract.
Adult ; Aged ; Conscious Sedation ; Contrast Media/diagnostic use ; Esophageal Neoplasms/radiography/*surgery ; Female ; Gastrostomy/*methods ; Humans ; Intestinal Obstruction/radiography/*surgery ; Iothalamate Meglumine/diagnostic use ; Laryngeal Neoplasms/radiography/*surgery ; Male ; Middle Aged ; Radiography, Interventional ; Retrospective Studies ; Upper Gastrointestinal Tract/radiography/*surgery