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41.
Silvio Taschieri Moses Ofer Stefano Corbella Tiziano Testori Claudia Dellavia Carlos Nemcovsky Elena Canciani Luca Francetti Massimo Del Fabbro Gianluca Tartaglia 《Materials》2020,13(22)
Aim: To evaluate the hypothesis of a correlation between the preoperative residual alveolar bone height (RBH) and graft maturation after maxillary sinus floor augmentation procedures using two different bone substitutes. Methods: A total of 20 patients who underwent unilateral maxillary sinus floor augmentation with either mineralized deproteinized bovine bone (DBBM) or a xenograft enriched with polymer and gelatin (NBS) were included in this prospective study. Six months after sinus surgery, bone biopsies were harvested with a 3.2 mm diameter trephine bur, prior to dental implant placement. Histomorphometric analysis was performed, and the results were correlated with the individual RBH. Implants were loaded after 5 months of insertion, and 1-year implant success and marginal bone level change were assessed. Results: RBH was 2.17 ± 1.11 mm (range 0.5–3.5 mm) and 2.14 ± 0.72 mm (range 0.5–3.0 mm) in the NBS and DBBM group, respectively. The biopsy analyses for the DBBM group showed woven bone increases by 5.08% per 1-mm increment of RBH; medullary spaces decreased by 9.02%, osteoid decreased by 4.4%, residual biomaterial decreased by 0.34%, and lamellar bone increased by 5.68% per 1-mm increase of RBH. In the NBS group, samples showed woven bone increases by 8.08% per 1-mm increase of RBH; medullary spaces decreased by 0.38%; osteoid increased by 1.34%, residual biomaterial decreased by 0.58%, and lamellar bone decreased by 5.50% per 1-mm increase of RBH. There was no statistically significant difference in the correlation between RBH and lamellar bone, woven bone, and osteoid, independently of the material used. Implant success was 100% in both groups, and marginal bone loss was 1.02 ± 0.42 mm in DBBM and 0.95 ± 0.31 mm in the NBS group after the 1-year follow-up. Conclusion: In spite of the absence of significance, the observed trend for woven bone to increase and medullary spaces to decrease when RBH increases deserves attention. Residual bone dimension might be a determinant in the bone graft maturation after maxillary sinus augmentation. 相似文献
42.
Ama Z. S. Rohatiner Matthew L. Smith Orietta Spinelli Alessandro Rambaldi Renato Bassan Eros di Bona Francesco Rodeghiero Roberto Raimondi Magnus Björkholm Steve Johnson Adrian C. Newland Jamie D. Cavenagh Finlay Macdougall Rachel Waters Jude Fitzgibbon Tiziano Barbui Andrew Lister 《British journal of haematology》2014,167(5):724-726
43.
Abdel-Wahab O Pardanani A Bernard OA Finazzi G Crispino JD Gisslinger H Kralovics R Odenike O Bhalla K Gupta V Barosi G Gotlib J Guglielmelli P Kiladjian JJ Noel P Cazzola M Vannucchi AM Hoffman R Barbui T Thiele J Van Etten RA Mughal T Tefferi A 《American journal of hematology》2012,87(5):562-568
Immediately after the annual scientific meeting of the American Society of Hematology (ASH), a select group of clinical and laboratory investigators in myeloproliferative neoplasms (MPN) is summoned to a post-ASH conference on chronic myeloid leukemia and the BCR-ABL1-negative MPN. The 6th such meeting occurred on December 13–14,2011, in La Jolla, California, USA, under the direction of its founder,Dr. Tariq Mughal. The current document is the first of two reports on this post-ASH event and summarizes the most recent preclinical and clinical advances in polycythemia vera, essential thrombocythemia,and primary myelofibrosis. 相似文献
44.
Randomized controlled trials (RCTs), typically, randomize participants to one of two intervention groups. It has been shown, however, that about 25% of RCTs published in the scientific literature randomize participants to three or more treatment groups. These studies are called ‘multi-arm’ trials: there may be, for instance, two or more experimental intervention groups with a common control group, or two control intervention groups such as a placebo group and a standard treatment group. A special case of multi-arm studies are factorial trials, which address two or more intervention comparisons carried out simultaneously, using four or more intervention groups.Key words: Factorial design, randomization, randomized controlled trial, study quality, treatment allocationRandomized controlled trials (RCTs), typically, randomize participants to one of two intervention groups (Cipriani & Geddes, 2009). It has been shown, however, that about 25% of RCTs published in the scientific literature randomize participants to three or more treatment groups (Chan & Altman, 2005). These studies are called ‘multi-arm’ trials: there may be, for instance, two or more experimental intervention groups with a common control group, or two control intervention groups such as a placebo group and a standard treatment group. A special case of multi-arm studies are factorial trials, which address two (or more) intervention comparisons carried out simultaneously, using four (or more) intervention groups. Most factorial trials have two ‘factors’, each of which has two levels (i.e., two possible groups of allocation); these are called 2 × 2 factorial trials. In a hypothetical 2 × 2 factorial trial, participants are randomized to one of four groups: one group receives both treatments A and B (AB), one receives only treatment A (A0), one only treatment B (B0), and the remaining group receives neither treatment A nor B (00) (see Randomization of treatment A Yes (A) No (0) Randomization of treatment B Yes (B) Both A and B (AB) B alone (B0) All B (AB and B0) No (0) A alone (A0) Neither A nor B (00) All non-B (A0 and 00) All A (AB and A0) All non-A (B0 and 00) Analysis ‘at the margins’