Bone physiology in human grafted and non-grafted extraction sockets--an immunohistochemical study.

PURPOSE: The aim of the present immunohistological investigation was to define and compare the osteogenic potential with the vascularization of the provisional matrix in grafted and ungrafted extraction sockets after 4 and 12 weeks of healing. METHODS: A total of 33 Patients (15 women, 18 men) with 65 extraction sites with a mean age of 54.4 years (30-73 years) participated in this study. After tooth extraction, the sockets were augmented with Bio-Oss collagen or non-augmented. At implant placement after 4 or 12 weeks bone biopsies were obtained. Within the specimens the osteogenic and endothelial potential of mesenchymal cells was analyzed in the provisional matrix using immunohistochemical analysis with three monoclonal antibodies Cbfa1/Runx2, Osteocalcin (OC), and CD31. Statistical analysis was performed using Mann-Whitney U-test, Spearman's rank-order correlation coefficient, and the two-factorial analysis for repeated measurements. RESULTS: Of the 65 extraction sockets, 25 (13 non-augmented, 12 augmented) sites after 4 weeks healing time and 40 (19 non-augmented, 21 augmented) sites after 12 weeks healing time were involved in the study. No signs of acute or chronic inflammation were noted in any specimens. After 4 weeks, a median amount of 56% (10-85%) of Cbfa1 positive cells and a median amount of cells expressing OC of 21% (5-42%) were measured. A median CD31 score of 5 was observed. After 12 weeks, a median amount of 61% (19-90%) positive cells expressed by Cbfa1/Runx2 staining a median amount of OC positive cells of 9% (2-17%) was measured. The results at 12 weeks revealed a median score of CD31 positive cells of 3. DISCUSSION: Osteoblastic activity in the provisional matrix was highest after 4 weeks of healing period. The active zone of bone formation is found in the apical region of the extraction socket during the early healing phase, shifting to the coronal region after 12 weeks. A peak of osteoblast activity within the first weeks is followed by a reduction in mature osteoblasts with osteoblasts remaining in an inactive stage. The vascularity changed in likewise fashion to the maturation of osteoblasts within the observation period. The results have shown that with increasing age a decreasing endothelial potential was observed not after 4 weeks, but after 12 weeks, thus it suggests that angiogenesis is diminished in older patients in the later phase of healing in extraction sockets.

Osteogenic potential of mesenchymal cells embedded in the provisional matrix after a 6-week healing period in augmented and non-augmented extraction sockets: an immunohistochemical prospective pilot study in humans.

PURPOSE: The aim of the present clinical study was the evaluation of the osteogenic potential of mesenchymal cells embedded in the provisional matrix of non-augmented and with Bio-Oss collagen-augmented human extraction sockets after 6 weeks of healing time. METHODS: Twenty-five patients with 47 extraction sites participated in the present study. After tooth removal, the extraction sockets were augmented with Bio-Oss collagen or not augmented. At implant placement, bone biopsies of the extraction sockets were obtained. The immunohistochemical analysis of the osteogenic potential of the mesenchymal cells in the provisional matrix was performed using three monoclonal antibodies: core-binding factor α1 (Cbfa1)/runt-related protein (Runx)2, osteonectin (OSN/secreted protein acidic and rich in cyst [SPARC]) and osteocalcin (OC). The statistical analysis was performed using two-factorial analysis for repeated measures, Mann-Whitney U-test and Spearman's rank-order correlation coefficient. RESULTS: Of 47 extraction sockets examined, 17 sockets demonstrated an almost complete ossification. Hence, the provisional matrix of the 30 remaining extraction sockets (21 non-augmented, 9 augmented) was immunohistochemically investigated. No evidence of acute or chronic inflammation was noted in any of the specimens. In the provisional matrix of the non-grafted socket, the median amount of Cbfa1/Runx2-positive cells was 72.3%, of OSN (SPARC) 66.9% and of OC 23.4%, whereas in the grafted sockets the median rate of immunopositive cells staining with Cbfa1/Runx2 was 73.3%, of OSN (SPARC) 61.4% and of OC 20.1%. There was no significant difference in the proportion of positive cells expressed by Cbfa1/Runx2, OSN/SPARC and OC between the grafted and non-grafted socket. Furthermore, the cell density did not correlate to the quantity of stained cells independent of the used proteins. DISCUSSION: After a 6-week healing period, the provisional matrix was demonstrated to have a high proportion of cells displaying a maturation of mature osteoprogenitor cells to osteoblasts. The grafting procedure did not influence the quantity of osteogenic cells in the extraction socket.

A prospective randomized split-mouth study comparing iliac onlay grafts in atrophied edentulous patients: covered with periosteum or a bioresorbable membrane.

PURPOSE: In this prospective study, solid monocortical iliac onlay grafts of the maxilla were randomly covered with a bioresorbable membrane and periosteum within the maxilla. Histologic specimens were analyzed by light microscopy after a healing period of three months and the rate of resorption of the grafts were measured. MATERIALS AND METHODS: Fourteen patients (9 females and 5 males), with a mean age of 56 years (range 25-72) underwent augmentation with avascular iliac onlay bone grafts. The grafts were randomly covered either with a bioresorbable membrane (MC) or periosteum (PC). Resorption was measured with a digital caliper at the microscrews (slashed circle 1.5 mm) used to fixate the graft. Histologic evaluation of the specimens derived from the graft with a trephine bur (slashed circle 2 mm) from the implant site at implant placement after a 3-month healing period. Statistical evaluation of the data was performed using Analysis of variance and the Wilcoxon signed rank test. RESULTS: Clinical appearance of the augmented bone after 3 months showed a dense cortical layer with good vascular perfusion. Thirty-three sites in 13 patients (one dropped put) were analyzed histomorphometrically and showed an average of 46% newly formed bone with no significant difference between the groups (P=0.46). The mean resorption rate at 56 measured sites was 1.2 mm (range 0.3-3.4 mm) after 3 months, with no significant difference between the MC sites and the PC sites (P=0.38). DISCUSSION: Histomorphometry of new bone formation after 3 months demonstrates no significant difference between the PC and MC groups. Initialization of graft resorption can be seen after 3 months with no significant difference as to whether the graft was covered with a membrane or the periosteum. CONCLUSION: This study provides evidence that after avascular iliac bone grafting, the revascularization of the graft was sufficient after 3 months regardless of the graft coverage with no effect on the amount of initial resorption of the graft.

A case of bone metaplasia of the gallbladder epithelium.

The case of a 53-year-old female with abdominal pain is presented. Abdominal ultrasound was unremarkable, a HIDA scan demonstrated biliary dyskinesia, and a computed tomography scan of the abdomen and pelvis revealed an intraluminal gallbladder hyperdensity suspicious for a gallstone. A laparoscopic cholecystectomy was performed and, on pathologic examination, no gallstones were present. Microscopically, a focus of bone metaplasia of the gallbladder mucosa was noted. No other lesions were identified. Bone metaplasia of the gallbladder is a rare event of unknown clinical significance that may be clinically confused with cholelithiasis affecting treatment options.

Extraintestinal manifestations of Edwardsiella tarda infection: a 10-year retrospective review.

Edwardsiella tarda, a member of the family Enterobacteriaceae found in aquatic environments, is an unusual cause of human disease, presenting most frequently as gastroenteritis. Extraintestinal manifestations of E. tarda infection are rare but have included meningitis, cholecystitis, endocarditis, osteomyelitis, soft tissue infections, bacteremia, and septicemia. Over a 10-year period at our institution, 10 cases of extraintestinal infection related to E. tarda were identified. The infections ranged from soft tissue infections secondary to trauma to intra-abdominal infections with abscess formation. Several of the patients had documented factors predisposing them to infection including diabetes mellitus and C1 esterase deficiency. Interestingly, two of the patients had chronic idiopathic inflammatory bowel disease, and one patient developed a respiratory tract infection related to E. tarda, a previously unreported clinical manifestion. Although the mortality rate for extraintestinal E. tarda infections has been as high as 50% in some studies, antimicrobial treatment was eventually successful in each of the 10 cases at our institution.

Diagnosis of linitis plastica-type gastric adenocarcinoma by endoscopic ultrasound-guided fine needle aspiration: a case report.

BACKGROUND: The diagnosis of linitis plastica-type adenocarcinomas of the stomach has traditionally been made by brush cytology and mucosal biopsy. These techniques may yield false negative results due to the often submucosal location of these lesions. CASE: A 46-year-old woman presented witb epigaseric abdominal pain and loss of abbetite. Computed tomography of her abdomen revealed diffuse thickening of a portion of the gastric wall. Subsequent endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) of the stomach yielded abundant single, discohesive malignant cells suspicious for lymphoma vs. poorly differentiated carcinoma. Special stains and immunohistochemical stains confirmed the diagnosis of poorly differentiated adenocarcinoma ofsignet ring cell type. CONCLUSION: As many linitisplastica-type adenocarcinomas are submucosal lesions, mucosal sampling by biopsy may yield nondiagnostic material in up to one third of cases. With its ability to sample deep submucosal lesions, EUS-FNA is an appropriate technique for establishing this diagnosis and guiding patient treatment.

Giardia lamblia infection diagnosed by endoscopic ultrasound-guided fine-needle aspiration.

The protozoan Giardia lamblia is a major cause of gastrointestinal disease worldwide. We report the case of a 59-yr-old male who presented to his primary care physician with complaints of abdominal pain and weight loss. Imaging studies revealed a liver mass and a pancreatic head mass. Biopsy of the liver mass proved to be benign, and endoscopic ultrasound-guided fine-needle aspiration of the mass in the head of the pancreas showed no evidence of malignancy; however, numerous pear-shaped, binucleated, flagellated organisms morphologically consistent with trophozoites of Giardia lamblia were identified in the specimen. With the increasing use of endoscopic ultrasound-guided fine-needle aspiration for sampling of gastrointestinal, hepatobiliary, and pancreatic lesions, cytopathologists examining such specimens will need to be familiar with the diagnostic characteristics of this protozoal parasite.

Healing of ungrafted and grafted extraction sockets after 12 weeks: a prospective clinical study.

PURPOSE: In this prospective study, bone formation in human extraction sockets augmented with Bio-Oss Collagen after a 12-week healing period was quantified and compared to bone formation in unaugmented extraction sockets. MATERIALS AND METHODS: Selected patients with four-walled extraction sockets were included in this prospective study. After extraction, the sockets were randomly augmented using Bio-Oss Collagen or left to heal unfilled without raising a mucoperiosteal flap. At the time of implant placement, histologic specimens were obtained from the socket and analyzed. Statistical analysis was performed using the Wilcoxon signed-rank test. RESULTS: Twenty-five patients with a total of 39 sockets (20 augmented, 19 unaugmented) were included in the study and the histologic specimens analyzed. All specimens were free of inflammatory cells. The mean overall new bone formation in the augmented sites was 25% (range, 8%-41%) and in the unaugmented sockets it was 44% (range, 3%-79%). There was a significant difference in the rate of new bone formation between the grafted and ungrafted sockets and a significant difference in the bone formation rate in the apical compared to the coronal regions of all sockets, independent of the healing mode. CONCLUSION: This descriptive study demonstrated that bone formation in Bio-Oss Collagen-grafted human extraction sockets was lower than bone formation in ungrafted sockets. Bone formation occurred in all specimens with varying degrees of maturation independent of the grafting material and was initiated from the apical region.

Complex, humanitarian emergencies : III. Measures of effectiveness

Complex humanitarian emergencies lack a mechanism to coordinate, communicate, assess, and evaluate response and outcome for the major participants (United Nations, International Committee of the Red Cross, nobgovernmental organization and military forces). Success in these emergencies will depend on the ability to accomplish agreed upon measures of effectiveness (MOEs). A recent civil-military humanitarian exercise demonstrated the ability of participants to develop consensus-driven MOEs.(AU)

Complex, humanitarian emergencies : III. Measures of effectiveness

Complex, humanitrian emergencie, lack a mechanism to coordinate, communicate, assess and evaluate response and outcome for the major participant (United Nations, International Committee of the Red Cross, nongovernmental organizations and military force). Success in these emergecies will depend on the ability to accomplish agreed upon measures of effectiveness (MOEs). A recent civil-military humanitarian exercive demostrated the ability of participants to develop consensus-driven MOEs. Measures of effectiveness have the potential to be a unifying disaster management tool and a partial solution to the communication and coordination problems inherent in these complex emergencies (AU)