Measurement of the zygomatic bone and pilot hole technique for safer installation of zygomaticus implants

The zygomaticus implant (Brånemark system, Nobel Biocare, Gotebörg, Sweden) was developed for patients with severe bone resorption of the posterior maxilla, which may eliminate or minimize the need for bone grafting. Although the zygomaticus implant has had a remarkable success rate in a difficult patient population, the method requires an advanced surgical technique and carries increased risk of complications, such as the perforation of the orbital floor or infratemporal fossa. Although it is important to have a detailed understanding of the anatomy of the zygomatic bone when performing the installation, there have been few anatomic studies on the zygomatic bone for installation of zygomaticus implants. In this study, we measured the height and thickness of the zygomatic bone for the installation. The thickness at a 90-degree angle point, where the upper margin of the zygomatic arch and the temporal margin of the frontal process of the zygomatic bone intersect and where the apex of the implant penetrates, according to the original method, was 1.8 ± 0.4 mm, which gradually increased inferiorly and anteriorly. In conclusion, the penetration point of the apex of the zygomaticus implant should be located more inferoanterior to the 90-degree angle point, as the thickness of the 90-degree angle point is thinner than the diameter of the implant. Based on these results, we have proposed a newer and safer installation method for the zygomaticus implant using a drill guide, which can be easily made

Preparation and evaluation of a radiogallium complex-conjugated bisphosphonate as a bone scintigraphy agent

金沢大学医薬保健研究域薬学系Introduction: 68Ga is a radionuclide of great interest as a positron emitter for positron emission tomography (PET). To develop a new bone-imaging agent with radiogallium, 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) was chosen as a chelating site and Ga-DOTA complex-conjugated bisphosphonate, which has a high affinity for bone, was prepared and evaluated. Although we are interested in developing 68Ga-labeled bone imaging agents for PET, in these initial studies 67Ga was used because of its longer half-life. Methods: DOTA-conjugated bisphosphonate (DOTA-Bn-SCN-HBP) was synthesized by conjugation of 2-(4-isothiocyanatebenzyl)-1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid to 4-amino-1-hydroxybutylidene-1,1-bisphosphonate (alendronate). 67Ga-DOTA-Bn-SCN-HBP was prepared by coordination with 67Ga, and its in vitro and in vivo evaluations were performed. Results: 67Ga-DOTA-Bn-SCN-HBP was prepared with a radiochemical purity of over 95% without purification. 67Ga-DOTA-Bn-SCN-HBP had great affinity for hydroxyapatite in binding assay. In biodistribution experiments, 67Ga-DOTA-Bn-SCN-HBP accumulated in bone rapidly but was hardly observed in tissues other than bone. Pretreatment of an excess amount of alendronate inhibited the bone accumulation of 67Ga-DOTA-Bn-SCN-HBP. Conclusions: 67Ga-DOTA-Bn-SCN-HBP showed ideal biodistribution characteristics as a bone-imaging agent. These findings should provide useful information on the drug design of bone imaging agents for PET with 68Ga. © 2010 Elsevier Inc. All rights reserved

全身麻酔下歯科治療

We report about general anesthesia for disabled patients with special needs or young children during dental treatment in Tokushima University Hospital. We have administered ambulatory anesthesia or general anesthesia with short-term hospitalization for the patients. In this report, we showed anesthesia as a behavior management technique and the system for the patients who schedule ambulatory anesthesia in our hospital. We indicated the present situation of dental treatment under general anesthesia and supposed the prospects of dental care for the patients with special needs