Peri-implant tissue healing in implant placed in post-extraction sockets of maxillary premolars.

AIM: The aim of this study was the clinical and radiographic evaluation of peri-implant tissues healing associated with two-stage implants performed with one-stage surgery and placed into post-extraction sockets of maxillary premolars. METHODS: Ten natural tapered submerged titanium implants with double acid-etched surface were installed in post-extraction sockets of maxillary premolars showing no bone dehiscence or fenestrations. Implants were selected according to the greatest dimension compatible to vertical and horizontal diameters of the post-extraction sockets. Peri-implant defects showing more than 2 mm of distance between the marginal palatal bone and the implant margin, were not treated with a regenerative procedure but with a bone swaging technique by means of piezoelectric surgery. At 16 weeks osteointegration of implants was examined with a clinical and standardized radiographic evaluation. RESULTS: All patients showed good clinical healing without any complication. At 16 weeks all implants, either those with reduced marginal defect or those with modified crestal bone profile, were osteointegrated. CONCLUSIONS: The use of two-stage implants performed with one-stage surgery in 4 walls post-extraction sockets of maxillary premolars, seems to allow osteointegration both in reduced peri-implant horizontal defects as well as in defects larger than 2 mm. Furthermore, these procedures seem to simplify the management of soft peri-implant tissues.

Atypical basal bodies in a cat with immotile-cilia syndrome.

Atypical basal bodies from the oviductal mucosa of a female, 2.5-years-old cat suffering from immotile-cilia syndrome are described. The microtubular pattern was observed in 250 cross-sectional basal bodies. Four basal bodies (1.6%) had a defective number of microtubular triplets resulting in the appearance of so-called 'half-centriole' type. Two out of 100 longitudinal basal bodies showed duplicating striated rootlets and only one had an additional set of nine subdistal appendages, so that two basal feet arose from a single basal body. Electron-dense material and isolated microtubules into the lumen of some basal apparatuses were occasionally seen. It is known that centrioles and basal bodies show an unusual degree of constancy in size, shape and geometrical configuration, so that their abnormalities are very rare.