A digital evaluation of alveolar ridge preservation at implants placed immediately into extraction sockets: an experimental study in the dog.

OBJECTIVE: To compare with pristine sites bone resorption and soft tissue adaptation at implants placed immediately into extraction sockets (IPIES) in conjunction with deproteinized bovine bone mineral (DBBM) particles and a collagen membrane. MATERIAL AND METHODS: The mesial root of the third premolar in the left side of the mandible was endodontically treated (Test). Flaps were elevated, the tooth hemi-sectioned, and the distal root removed to allow the immediate installation of an implant into the extraction socket in a lingual position. DBBM particles were placed into the defect and on the outer contour of the buccal bony ridge, concomitantly with the placement of a collagen membrane. A non-submerged healing was allowed. The premolar on the right side of the mandible was left in situ (control). Ground sections from the center of the implant as well as from the center of the distal root of the third premolar of the opposite side of the mandible were obtained. The histological image from the implant site was superimposed to that of the contralateral pristine distal alveolus, and dimensional variation evaluated for the hard tissue and the alveolar ridge. RESULTS: After 3 months of healing, both histological and photographic evaluation revealed a reduction of hard and soft tissue dimensions. CONCLUSION: The contour augmentation performed with DBBM particles and a collagen membrane at the buccal aspects of implants placed IPIES was not able to maintain the tissue volume.

A cone beam tomographic evaluation of hard tissue alterations at immediate implants: a clinical prospective study.

The aim of this study was to investigate the hard tissue alterations of the alveolar bone crest following tooth extraction and immediate implant placement using cone beam computed tomography. Twelve consecutive patients in need of an immediate dental implant were included in the study. An implant of proper length was placed in the extraction socket with the coronal margin of the rough surface generally flush with or deeper than the buccal alveolar bone crest. All patients underwent a radiologic examination both immediately after implant placement (T1) and at the time of reentry 4 months after surgery (T2). The survival rate of 12 immediate implants at 4 months was 100%. Only 9 of 12 patients completed the study. The comparison between tomographies performed at T1 and T2 showed substantial variations in alveolar bone, mainly at the buccal aspect, registering a vertical gain of about 3.2 mm. The horizontal resorption of the alveolar bone crest appeared to be more marked at the buccal than at the lingual aspects. At the buccal aspect, the resorption was 1.9 mm, 1.0 mm, and 0.6 mm at the measurements performed at 1, 3, and 5 mm apical to the crest, respectively. At the lingual aspect, the corresponding values were 0.6 mm, 0.7 mm, and 0.5 mm, respectively. The bone crest area was more or less the same at T1 and T2, while the total area decreased after 4 months of healing but was not statistically significant. The results should be viewed with caution because of the small number of cases examined. The results confirm the success of immediate implant placement.

[Gastric carcinoid: case report and review of the literature]. / Carcinoide gastrico. Presentazione di un caso e revisione della letteratura.

Carcinoids are rare tumour of neuroendocrin origin, characterized by argyrophylic silver stain reaction, positive immunohistochemical reaction with neuron-specific markers, a typical growth pattern; they can express different peptides and biogenic amines. Gastric carcinoid tumours have been classified on the basis of susceptibility to gastric trophic stimulus and characteristics mucosal surrounding into 3 different types. This classification is important with respect to therapeutic strategy (type adapted treatment), but the option of endoscopic or surgical treatment is influenced by the impossibility to distinguish clearly the benignity or malignity of these lesions. A review of international literature and a rare case of gastric carcinoid tumour associated with chronic athrophic gastritis, developed in a female 65-years old, with anaemia and treated by subtotal gastrectomy, are presented.