78 research outputs found
Maxillary sinus augmentation in humans using cortical porcine bone: a histological and histomorphometrical evaluation after 4 and 6 months
Background: Bone substitutes, such as allografts, xenografts, and alloplasts, have been proposed in several augmentation procedures. Purpose: The aim of the present study was a histologic and histomorphometric evaluation of specimens retrieved 4 or 6 months after sinus augmentation using cortical porcine bone augmentation material. Materials and Methods: A total of 77 specimens, retrieved after 4 and 6 months from augmented sinuses, were used in this study. The specimens were processed to be observed under light microscopy. Histomorphometric measurements were presented as means 1 standard deviations. Results: Most of the particles were surrounded by newly formed bone with large osteocyte lacunae. Histomorphometry showed that, after 4months, the newly formed bone represented 28%, marrow spaces 36%, the residual graft material 37%, while, after 6 months, the newly formed bone represented 31%, marrow spaces 34%, while the residual graft material was 37%. Conclusion: The present results show that cortical porcine bone is a biocompatible, osteoconductive biomaterial that ca
Adenocarcinoma arising in a Warthin’s tumor
SummaryCarcinoma ex pleomorphic adenoma is a well-recognized entity, while, in rare cases carcinomas may arise from the epithelial component of Warthin’s tumor. We present a case of adenocarcinoma arising in a Warthin’s tumor located in the left parotid gland in a 49-years-old patient. Chest X-ray, laboratory investigation and thyroid scintigraphy were normal. A ultrasonography and computerized axial tomography showed multiple nodules. A fine needle aspiration biopsy showed typical features of Warthin’s tumor. The histology showed the presence of a metastatic adenocarcinoma, that was thyroglobulin and calcitonin negative. The patient underwent a total left parotidectomy, was carefully followed-up, and at a 7 years check-up visit no other primary malignant lesion has manifested
The Effect of One-Abutment at One-Time on Marginal Bone Loss Around Implants Placed in Healed Bone: A Systematic Review of Human Studies
none5siThe primary aim of the present article was to review the effect and the clinical significance of abutment dis- and reconnection on the peri-implant marginal bone levels.openPerrotti, Vittoria; Zhang, Daniel; Liang, Andrew; Wang, Jonathan; Quaranta, AlessandroPerrotti, Vittoria; Zhang, Daniel; Liang, Andrew; Wang, Jonathan; Quaranta, Alessandr
Factors associated with apoptosis in symptomatic and asymptomatic carotid atherosclerotic plaques.
The aim of this study was to investigate the differences that are present between apoptosis in symptomatic (with symptoms of cerebral ischemic attack) and asymptomatic carotid atherosclerotic plaques. The apoptotic process in macrophages and smooth muscle cells was evaluated. Cellular markers and products of immune cells in symptomatic and asymptomatic atherosclerotic plaque and endoarterectomy specimen were analyzed by immunohistochemistry. No statistically significant differences were present regarding the mean SMC actin-positive area. Using double staining of α-smooth muscle actin and TUNEL techniques, the number of smooth muscle cells in apoptosis was statistically higher in symptomatic plaque as compared with asymptomatic plaque. Statistically significant differences (p=0.009) were also found in the CD45-positive cells in the inflammatory infiltrate. The CD68-positive macrophages showed statistically significant differences (p=0.0001). Similarly, the double staining with CD68 and TUNEL revealed that apoptotic macrophages were mainly present in asymptomatic plaques rather than symptomatic plaques. Statistically significant differences (p<0.001) were found in the Bcl-2 expression, with higher values in asymptomatic plaques. Our data showed that the increase of the inflammatory cells contributes to plaque instability and that death due to apoptosis of smooth muscle cells in symptomatic plaques could contribute to their destabilization and explains their tendency to fracture
A site-specific intraoperative measurement of bone-to-implant contact during implant insertion: A study on bovine ribs using a computerized implant motor
Background/purpose: The aim of the current in vitro study was to determine if there was a correlation between the integrals (I) of the function cutting resistance/depth, obtained using a computerized implant motor, and the bone-to-implant contact (BIC) percentages of dental implants inserted in bovine ribs. Materials and methods: Segments of bovine ribs were used, and a total of 21 perforations were performed. A total of 21 dental implants were inserted in the prepared bone sites. A computerized implant motor ("Torque Measuring Motor") was used to assess, before implant insertion, the values of the bone cutting resistance. The data of bone density obtained by the implant motor were statistically correlated with the BIC percentages. Results: A significant positive linear correlation was found between the integrals measured by the implant motor and the BIC assessed by histomorphometry (r = 0.78, n = 21, P < 0.0001). Indeed, the increase of the integral values recorded by the reader matched with the increase of BIC percentages measured by histomorphometry. Pearson correlation coefficient for linear regression (R2) between values assessed by the surgical motor and histomorphometry was 0.61 (P < 0.0001), indicating that 61% of the data points were aligned with the regression line. Conclusion: The instrument under testing seems to provide a reliable quantitative estimator, the integral, of the final BIC achieved at implant insertion, and therefore of the implant primary stability, and could represent a significant aid for a proper planning of rehabilitations with the use of dental implants
S100A8 calcium-binding expression in radicular and dentigerous cysts and in keratocystic odontogenic tumors
Introduction: Recently the term Keratocystic Odontogenic Tumor (KCOT) has been recommended for Odontogenic Keratocysts (OKC) to address the neoplastic nature of the lesion compared to radicular and dentigerous cysts. S100 are calcium-binding proteins involved in cell differentiation and inflammation, with a potential role in neoplastic transformation. Aim: The aim of this study was to evaluate whether S100A8 protein expression is different in KCOT compared to radicular cysts (RC) and dentigerous cysts (DC). Methods: A total of 84 consecutive odontogenic cysts, 34 RC, 25 DC, and 25 KCOT, were analyzed in this study. Results: Epithelial cells in KCOT cases were not immunoreactive for S100A8 except focally in cases associated with inflammation, while RC cases showed a variable positivity of all the epithelial layers from the basal to the superficial in 19/34 cases and DC cases showed a weak positivity of the intermediate and superficial layers in 7/25 cases. Conclusion: The lack of S100A8 protein expression seems to be observed more frequently in KCOT compared to RC and DC. This difference might be related to their neoplastic nature and a potential aggressive biological behavior for odontogenic cystic lesions
Implant insertion in a patient with Albers-Schonberg’s disease: case report and literature review
Background The aim of the present report was to present the clinical, radiological and histological outcomes of a case of implant placement in the upper jaw of a patient affected by osteopetrosis. Case report In a 68 years old patient, 2 implants were placed in a portion of bone with areas with high density bone. Histological evaluation confirmed the radiological diagnosis of osteopetrosis. Implants were loaded 8 months after their placement. No complications or adverse reactions were observed after a 24-month follow up. Conclusion Within the limitations of the present report, it can be concluded that a successful implant rehabilitation can be done in patients affected by osteopetrosis. Further studies, on a larger sample size, are needed to confirm this result
A Randomized Pilot Clinical and Microbiological Study Comparing Laser Microtextured Implants with and without Platform Switching
Minimising marginal bone loss around dental implants is of paramount importance. The success of methods such as platform switching (PS) and laser-micro-texturing (LM) are well documented. Whether or not a combination of these designs will further improve outcomes has not been studied previously. Hence, this prospective, randomized controlled single-centre pilot study compared the clinical and microbiological outcomes of implants with both PS and LM (test) to implants with only LM (control). A test and control implant were placed in thirteen patients totalling 26 implants. The primary investigated outcome was marginal bone level (MBL); secondary outcomes were peri-implant probing depths (PPD), bleeding on probing (BOP) and marginal tissue height (MTH). Additionally, the presence of five putative periodontal pathogens were assessed using real-time polymerized chain reaction. At 12 months the overall implant survival rate was 95.8%. MBL change was not found to be different between test and control at any time points, but a significant change was detected within the test implants at 6 months compared to baseline (p = 0.006). No differences were found in the secondary outcomes. Average PPD at 12 months was 2.68 ± 0.73 mm and 2.30 ± 0.46 mm and average change in MTH was 0.05 ± 0.72 mm and −0.24 ± 0.59 mm at tests and controls. No differences were reported in BOP frequency. Total periodontal pathogens count revealed no significant difference among control, test implants and adjacent tooth sites. Within the limitations of this study, it can be concluded that the addition of PS to LM implants does not significantly alter either short-term clinical outcomes or the vulnerability to pathogenic microflora colonization
Sealing capability of implant-abutment junction under cyclic loading: a toluidine blue in vitro study
Implant insertion in a patient with Albers-Schonberg's disease: Case report and literature review
Background The aim of the present report was to present the clinical, radiological and histological outcomes of a case of implant placement in the upper jaw of a patient affected by osteopetrosis. Case report In a 68 years old patient, 2 implants were placed in a portion of bone with areas with high density bone. Histological evaluation confirmed the radiological diagnosis of osteopetrosis. Implants were loaded 8 months after their placement. No complications or adverse reactions were observed after a 24-month follow up. Conclusion Within the limitations of the present report, it can be concluded that a successful implant rehabilitation can be done in patients affected by osteopetrosis. Further studies, on a larger sample size, are needed to confirm this result
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