Air-abrasive debridement with glycine powder versus manual debridement and chlorhexidine administration for the maintenance of peri-implant health status: a six-month randomized clinical trial.

STUDY DESIGN: This single-masked, randomized and six-month clinical intervention trial including two study groups was planned to evaluate the efficacy of maintenance treatment with glycine powder on the periodontal health of peri-implant tissues. METHODS: A total of 46 patients with partial or total edentulism, carrying a total of 88 implants, were assigned either to an air abrasive with the glycine powder treatment group (AAD) or to a manual debridement and clorexidine administration treatment group (MDA). Clinical data were collected before treatment and at 3 and 6 months after the treatment. Plaque index (PI), bleeding index (BOP), probing depth (PD), clinical attachment level (CAL) and bleeding score (BS) were analysed. RESULTS: After 3 months, AAD treatment statistically significantly improved BS (P < 0.05); at 6 months, AAD treatment statistically significantly improved indexes PD, PI, BOP and BS (P < 0.05). In addition, the AAD treatment proved to be more effective than MDA in maintaining the peri-implant health of PD at three and 6 months, and of PI at 6 months (P < 0.05). There were no significant changes of CAL in both groups, and all the indexes remained within the physiological levels. CONCLUSIONS: Within the limits of the study, treatment with glycine seems appropriate in the maintenance of peri-implant health and more effective than the traditional treatment with plastic curette and chlorhexidine.

Extrusion of severely impacted mandibular first molar using partial orthodontics and temporary anchorage miniscrews.

BACKGROUND: This study reports a case in which a severely impacted lower first molar was recovered with a combined orthodontic therapy and minimally invasive oral surgery with special focus to patient's aesthetic demands. CASE REPORT: A 12-year- old female patient was complaining delayed eruption of mandibular right first molar. Radiographic exam showed a severe tooth impaction with a close relationship between tooth roots and mandibular nerve. As the patient refused full arches orthodontic treatment, a partial orthodontic approach was projected. During treatment, temporary miniscrews were placed in both upper and lower arches, in order to allow dental movement with maximum anchorage. After a 24 month-therapy the tooth was extruded, so the appliance and the miniscrews were removed. CONCLUSION: The present case shows that severe tooth impaction can be resolved with a combined partial orthodontic- minimally invasive surgical treatment.

Retrospective analysis of 521 endosseous implants placed under antibiotic prophylaxis and review of literature.

AIM: Antibiotic prophylaxis in surgical implants has not a consensus in the scientific world. This is due both to reports and statistical studies with contradictory results, both to the risk of severe anaphylactic reactions and the emergence of antibiotic resistance and, finally, to the lack of published RCTs. The purpose of this study is to retrospectively analyze and assess the success of surgical therapy with endosseous implants inserted under antibiotic prophylaxis at the Department of Oral Sciences "S. Palazzi", University of Pavia. The data presented are compared to those published in international literature. The work is complemented by a statistical data analysis in order to propose a statistically valid judgement on the effectiveness of antibiotic prophylaxis in preventing postoperative infections. METHODS: Retrospective observational study with an average follow-up of 4.5 months, until the abutment connection. Furthermore, after extensive review of the literature, published data are compared with what retrieved in our department. Patients operated consecutively from June 2002 to December 2007. Review of literature data concerning the influence of antibiotic prophylaxis on the implant success. RESULTS: The data relating to post-operative complications encountered at the Division of Oral Surgery, University of Pavia and the comparison with those presented in the bibliography indicate statistically significant differences in favor of the antibiotic prophylaxis used in our department. CONCLUSION: There were no anaphylactic reactions recorded. It seems advisable to perform implantology with prophylactic antibiotic coverage.

Cytopathological and chemico-physical analyses of smears of mucosa surrounding oral piercing.

OBJECTIVE: The aim of this comparative study was to analyze cytopathologically and chemico-physically the mucosa surrounding oral piercing to correlate results with adverse tissue signs. MATERIALS AND METHODS: The tongue superficial mucosa of 15 young subjects (control group) and the superficial mucosa surrounding oral piercing of 15 young subjects (test group, TG) were smeared on slides, Papanicolaou stained and analyzed under the optical microscope. Some smears were prepared for (back-scattered) scanning electron microscope (SEM) and X-ray microanalysis to study piercing fragments. RESULTS: Smears of TG displayed a variable extent of bacterial cytolysis of epithelial cells, fungi, hyperkeratosis, parakeratosis, granulocyte infiltration, calcium formations and bacterial flora; the four last statistically significant (P < 0.05). Foreign bodies surrounded by keratinocytes were detected under both light and SEM. X-ray microanalyses highlighted piercing alloy aggression, ion release and an inverse gradient of ion concentration inside keratinocytes. CONCLUSIONS: The pathological findings in smears correlated with adverse effects of oral piercing. Ion release may be related to direct toxic effects and belated reactions because of metal sensitization. A strict regulation of piercing is warranted.

Multifunctional implant surfaces: surface characterization and bone response to acid-etched Ti implants surface-modified by fibrillar collagen I.

The goal of the study was the evaluation of the effect of biochemical surface modification by collagen on the bone response to acid-etched titanium surfaces. Fibrillar type I porcine collagen was adsorbed and covalently linked to acid-etched Ti disks and implants. Adhesion, growth, and specific alkaline phosphatase (ALP) activity of osteoblast-like SaOS2 cells were evaluated. Implants in the femur and tibia of rabbit were performed for 2 and 4 weeks and relevant bone to implant contact (BIC) was evaluated by histomorphometry. Results show that cell morphology and growth are controlled by the rough acid-etched implants topography. Specific metabolic activity (ALP) is significantly increased by the collagen overlayer. Importantly, surface modification by collagen increases the speed of periimplant bone formation, resulting in significantly higher BIC both in femur and tibia at 2 weeks. These results suggest that morphological (surface topography) and biochemical (surface linking of bioactive molecules) cues can cooperate and yield multifunctional implant surfaces. (c) 2010 Wiley Periodicals, Inc. J Biomed Mater Res, 2010.

The microvascular network of the pituitary gland: a model for the application of fractal geometry to the analysis of angioarchitecture and angiogenesis of brain tumors.

In geometrical terms, tumor vascularity is an exemplary anatomical system that irregularly fills a three-dimensional Euclidean space. This physical characteristic, together with the highly variable vessel shapes and surfaces, leads to considerable spatial and temporal heterogeneity in the delivery of oxygen, nutrients and drugs, and the removal of metabolites. Although these biological features have now been well established, quantitative analyses of neovascularity in two-dimensional histological sections still fail to view tumor architecture in non-Euclidean terms, and this leads to errors in visually interpreting the same tumor, and discordant results from different laboratories. A review of the literature concerning the application of microvessel density (MVD) estimates, an Euclidean-based approach used to quantify vascularity in normal and neoplastic pituitary tissues, revealed some disagreements in the results and led us to discuss the limitations of the Euclidean quantification of vascularity. Consequently, we introduced fractal geometry as a better means of quantifying the microvasculature of normal pituitary glands and pituitary adenomas, and found that the use of the surface fractal dimension is more appropriate than MVD for analysing the vascular network of both. We propose extending the application of this model to the analysis of the angiogenesis and angioarchitecture of brain tumors.

Intramedullary astrocytoma with granular cell differentiation.

Granular cell astrocytomas are uncommon tumors of the central nervous system (CNS) of which no cases have been documented in the spinal cord. This variant of glioma should not be confused with benign granular cell tumor which, although rare, has been well characterized in the spinal cord. We describe here the clinical, pathological, and radiological features of such an astrocytoma arising within the spinal cord at the dorsal level. A 48-year-old female was seen after about 1 year of dorsal pain and gradual spastic paraparesis. Magnetic resonance imaging (MRI) studies showed a 2-cm contrast-enhanced mass in the spinal cord at T6-T7, which had the appearance of an astrocytoma. At surgery, the tumor was found to be infiltrating a posterior column with no dural attachment. It was debulked and dissected. The histological diagnosis was astrocytoma with granular cell differentiation. In addition to documenting a unique example of intramedullary granular cell astrocytoma, we review the literature to investigate differences from other tumors with granular changes described in the spinal cord.

De novo Formation of the Ventriculus Terminalis? A Brief Report of a Special Case.

The ventriculus terminalis is an ependymal cystic cavity in the conus medullaris, sometimes found in children. Persistence of the ventriculus terminalis in adults can cause lower back pain or neurological disturbances. However, there are no literature reports of de novo formation of a ventriculus terminalis in the conus medulallaris, as in the case we illustrate here.

Oligodendroglial gliomatosis cerebri. Case report.

Gliomatosis cerebri of oligodendroglial origin is very unusual. In the present article we illustrate a case of this pathology, outlining his severity and suggesting it seems to be more aggressive than the astroglial type. We give a short focus about the diagnosis and the therapy of this neoplastic disease.

Arnold's neuralgia caused by solitary fibrous tumor. Case report.

Solitary fibrous tumor (SFT) is a mesenchymal tumor which has been identified in a wide variety of localizations, including soft tissues, peritoneum, retroperitoneum, mediastinum, upper respiratory tract, nasopharyngeal sinuses, periosteum and extremities, orbit, major body cavities, intraspinal and intracranial localizations. The authors describe a case of SFT found in the neck of a young patient suffering from Arnold's neuralgia. After surgery, diagnosis of SFT was based on characteristic histopathological findings, especially on immunohistochemical positive staining for CD34 antigen. It has been described also the characteristic patterns making this diagnose sure, focusing the point that cure is possible with complete excision of the lesion.

Intradural spinal metastasis of renal clear cell carcinoma causing cauda equina syndrome.

Metastasis of renal clear cell carcinoma to the spinal cord are quite rare. Intradural localization causing a cauda equina syndrome has been previously reported only in two cases. The present report details the clinical, surgical and neuroradiological findings of a third case requiring emergency surgery, and presents data available from a brief review of cases reported in the literature. From the data available in the literature, we suggest that cerebral and spinal MRI and PET imaging should be widely performed in the staging of patients treated for renal clear cell carcinoma, in order to early detect CNS involvement.

Meningeal melanocytoma of the temporal lobe. An uncommon tumor in an unusual location. Case report.

Meningeal melanocytomas are rare pigmented tumors of the central nervous system. These tumors are benign melanotic lesions that derive from the melanocytes of the leptomeninges. They may occur anywhere in the cranial and spinal meninges; however, they are found prevalently in the posterior fossa and in the spinal cord. Their epidemiological features, natural history and response to treatment remain poorly understood, even if, in the last 2 years, some reviews have been published about it. We report a new case of intracranial supratentorial meningeal melanocytoma, in the temporal lobe, occurring in a 27-year-old man, admitted to our Institute with a long-time history of seizures. We report histological and radiological characteristics of our case, and briefly review the therapeutical options reported in literature. Preoperative neuroradiological finding is unclear; the preoperative diagnosis is usually meningioma, because of the long duration of symptomatology and the radiological appearance of the lesion as an extra-axial mass. Diagnosis of these lesions, as in our case, is made intraoperatively by the gross, jet-black appearance of the tumor and by histological examination. In spite of the benign biologic behaviour, the prognosis remains uncertain, because of the possible local recurrences. According to the results of some works of the last years, it seems appropriate to use postoperative radiotherapy for those patients with symptomatic residual, progressive or recurrent tumors not amenable to further resection.

Isolated cerebellar involvement in Rosai-Dorfman disease: case report.

OBJECTIVE AND IMPORTANCE: Sinus histiocytosis or Rosai-Dorfman disease (RDD) is a rare but well-recognized disorder characterized by an unusual proliferation of histiocytic cells. Intracranial localization is a rare manifestation of RDD. Only three cases of localization in the posterior fossa have been reported in the literature. The present report describes the first case, to our knowledge, of cerebellar localization of RDD. CLINICAL PRESENTATION: A 67-year-old woman was admitted to our institution with a 5-month history of cerebellar ataxia. Her medical history was unremarkable. The patient was alert and cooperative. No cranial nerve deficits were evident; Romberg positivity to the left side was recorded. No cutaneous abnormalities, lymphadenopathy, or hepatosplenomegaly were revealed by physical examination. Routine hematological and biochemical studies were normal except for the erythrocyte sedimentation rate, which was elevated. Radiologically, the lesion appeared as a well-defined and avascular mass in the right cerebellar lobe. Meningioma was considered the most likely diagnosis. TECHNIQUE: The patient underwent a suboccipital craniotomy with complete excision of the lesion. Microscopic examination of the operative specimen revealed the presence of a mixed cellular population with predominant mature histiocytes. A peculiar feature was the presence of lymphocytes and monocytes within the cytoplasm of histiocytes (emperipolesis). Immunohistochemical study of the histiocytes revealed strong positivity for S-100, CD-68 antigen, and vimentin. CONCLUSION: Involvement of the central nervous system in RDD appears to have a benign prognosis, especially in the absence of nodal diseases. Surgery is essential for diagnosis, and, when total removal is achieved, the outcome is generally good without risk of recurrence.

Collagenase-1 and stromelysin distribution in fresh human herniated intervertebral disc: a possible link to the in vivo inflammatory reactions.

Chondrocytes may play an important role in the inflammatory reactions involving intervertebral discs: the role of metalloproteases (MMP) and the imbalance between proteases and their inhibitors seems to play a crucial role in the disc degenerative process. In the present study we have analysed the production of collagenase-1 and stromelysin in different parts of herniated intervertebral discs. Ten samples of herniated lumbar discs were obtained from adult patients operated on for primary microdiscectomy because of persistent radicular symptoms and subdivided into three samples: 1. The nearest to the nerve root in close contact with it, 2. the sample obtained from the intervertebral space, and 3. the sample obtained from the vertebral plates. The DNA content of each specimen was measured in order to obtain the best estimate of the cell content as well as to normalise the content of collagenase-1 and stromelysin found in the same tissues with respect to the number of cells. In 9 out of the 10 cases the DNA content was significantly higher in samples obtained from the intervertebral plates than in samples obtained near the nerve root or the intervertebral space. DNA content did not show any significant difference considering disc samples contiguous to the nerve root and samples obtained from the intervertebral space. The production of collagenase-1 did not show a specific pattern, being produced in similar quantities in the three disc compartments. The production of stromelysin was significantly lower in disc samples obtained from the intervertebral plates. In conclusion the results of the present study suggest firstly that in the herniated lumbar disc the reactivity and the production of pro-inflammatory agents is independent of DNA content, i.e. the cellularity of the sample, and secondly that activated cells in the intervertebral space and in the part of the disc in contact with the nerve root, even if scarce in number, are able to synthesise a proportionally higher quantity of MMP than the high-cellular disc fragments from the intervertebral plates, potentially playing a specific role in the inflammatory reactions.

Metalloproteases and intracranial vascular lesions.

Recent studies have suggested that metalloproteinases (MMP) might be involved in the pathogenesis of cerebral aneurysm formation and rupture and that elevated serum levels of MMP may effectively be considered as possible markers of cerebrovascular malformations. The present study was planned in order to verify if serum levels of MMPs may be the mirror of the MMP activity in the wall of intracranial aneurysms, reflecting the predisposition to aneurysm development and/or rupture. A series of 84 patients operated for intracranial cerebrovascular lesions (63 aneurysms and 21 arterovenous malformations (AVM)) and 20 controls entered the study. Among the 63 cases of intracranial aneurysms, nine were discovered before rupture, while 54 patients were included after subarachnoid hemorrhage (SAH). Using radioimmunoassay, plasma elastase levels were measured in all cases, while in 25 cases, when aneurysmectomy was possible, the activity of elastase and collagenase were measured in aneurysm samples. Mean plasma elastase level in patients bearing both an intracranial aneurysm or an intracranial AVM was significantly higher than in controls, while there was no significant difference between plasmatic level of elastase in patients with aneurysms when compared with patients bearing an intracranial AVM; there was no significant difference between mean elastase level in patients who suffered SAH and patients bearing an intracranial unruptured aneurysm. The activity of elastase and collagenase measured in the aneurysm wall were significantly higher in cases of ruptured than in unruptured aneurysms. The present results show that plasmatic level of elastase does not reflect the activity of MMP as measured in the aneurysm wall and that the patterns of MMP activities measured in the aneurysm wall differ considerably at different stages of SAH. This suggests that local rather than systemic changes in metalloproteases activity might be involved in cerebral aneurysm formation and rupture.

Collagenase-I and stromelysin distribution in fresh human herniated intervertebral disc: A possible link to the in vivo inflammatory reactions.

Chondrocytes may play an Important role in the inflammatory reactions involving intervertebral discs: the role of metalloproteases (MMP.) and the imbalance between proteases and their inhibitors seems to play a crucial role in the disc degenerative process. In the present study we have analysed the production of collagenase-1 and stromelysin in different parts of herniated intervertebral discs. Ten samples of herniated lumbar discs were obtained from adult patients operated on for primary microdiscectomy because of persistent radicular symptoms and subdivided into three samples: 1. The nearest to the nerve root in close contact with it, 2. the sample obtained from the intervertebral space, and 3. the sample obtained from the vertebral plates. The DNA content of each specimen was measured in order to obtain the best estimate of the cell content as well as to normalise the content of collagenase-1 and stromelysin found in the same tissues with respect to the number of cells. In 9 out of the 7 0 cases the DNA content was significantly higher in samples obtained from the intervertebral plates than in samples obtained near the nerve root or the intervertebral space. DNA content did not show any significant difference considering disc samples contiguous to the nerve root and samples obtained from the intervertebral space. The production of collagenase-1 did not show a specific pattern, being produced in similar quantities in the three disc compartments. The production of stromelysin was significantly lower in disc samples obtained from the intervertebral plates. In conclusion the results of the present study suggest firstly that in the herniated lumbar disc the reactivity and the production of pro-inflammatory agents is independent of DNA content, i.e. the cellularity of the sample, and secondly that activated cells in the intervertebral space and in the part of the disc in contact with the nerve root, even if scarce in number, are able to synthesise a proportionally higher quantity of MMP than the high-cellular disc fragments from the intervertebral plates, potentially playing a specific role in the inflammatory reactions. [Neurol Res 1999; 21: 677-681].

Oxidative stress in the human brain after subarachnoid hemorrhage.

OBJECT: The aim of this study was to verify the patterns of antioxidant enzymatic activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) in the human brain after subarachnoid hemorrhage (SAH) to verify whether an "oxidative stress situation" characterizes the brain response to subarachnoid bleeding. METHODS: Forty samples of gyrus rectus or temporal operculum that were obtained during a surgical approach to anterior circulation aneurysms were used for this study. The activity of total SOD, GSH-Px, and the SOD/GSH/Px ratio (which expresses the balance between the production of hydrogen peroxides by dismutation of superoxide radicals and the scavenging potential) were calculated in each case. Twelve samples were obtained from patients who underwent surgery for unruptured aneurysms (control group); 13 samples were obtained during surgical procedures performed within 72 hours of SAH; and 15 samples were obtained during delayed surgical procedures (> 10 days post-SAH). Ten patients presented with clinical deterioration caused by arterial vasospasm. In both SAH groups, the mean total SOD activity was significantly higher than in the control group (p=0.029). The mean activity of GSH-Px did not differ significantly between the SAH and control groups (p=0.731). There was a significant increase in the SOD/GSH-Px ratio in both SAH groups, as compared with controls (p < 0.05). There was a significant correlation between the enzymatic activity and the clinical severity of the hemorrhage, with findings of lower values of SOD and, mainly, of the SOD/GSH-Px ratio in the poor-grade patients. The SOD/GSH-Px ratio was 2.14+/-0.44 in patients who presented with clinical vasospasm and 1.24+/-0.2 in cases without vasospasm. CONCLUSIONS: The results of this study show an imbalance of the antioxidant enzymatic activities in the human brain after SAH. which is linked to the severity of the initial bleeding and possibly modified by the development of arterial vasospasm.

A cost-effectiveness analysis on different surgical strategies for intracranial aneurysms.

BACKGROUND: Economical studies on surgery of intracranial aneurysms have considered only the significant benefit of surgical approach on unruptured aneurysms and no studies have been performed comparing cost/benefit analysis of early vs delayed surgery. The present study was retrospectively performed in order to verify whether different treatment options in aneurysm surgery have a different cost/benefit ratio. METHODS: We have analysed a series of 137 patients which underwent surgery for intracranial aneurysms (21 unruptured aneurysms, 56 early surgery and 60 delayed surgery). In the analysis we assumed that each state of an operated patient has an assigned quality of life value and an associated medical cost. We expressed the outcome of each patient as the expected length of survival adjusted for quality, and referred to it as "quality-adjusted life years" (QALY). We considered for each patient the direct cost of Hospitalisation (obtained from DRG reimbursement), the Rehabilitation cost and the correction due to QALY adjusted for age and deficit. RESULTS: Significantly higher costs are reported in patients which present as major complication the hydrocephalus and which are treated with nimodipine; moreover, the costs for patients operated for unruptured aneurysms is significantly lower than that of patients which presented with SAH. Meanwhile, the average QALY adjusted for post-operative neurological deficit at three months follow-up is higher in patients operated for unruptured aneurysms than in patients operated after SAH. The cost-effectiveness of different treatment strategies did not significantly differ considering age and neurological deficit adjustment; thus, after SAH, the choice of early or delayed surgery may depend on clinical and logistic conditions related to the neurosurgical department and its organisation, because there is no significant economical advantage leading to recommend early versus delayed surgery. CONCLUSIONS: In conclusion the present data suggest that a decreased length of hospitalisation and a decreased cost for treatment of unruptured aneurysms should justify a more rigorous preventive screening with available non invasive neuroimaging techniques.

Antioxidant status and alpha1-antiproteinase activity in subarachnoid hemorrhage patients.

The antiproteasic activity of alpha1-antitrypsin (alpha1-AT) is reduced in cases of subarachnoid hemorrhage from ruptured intracranial aneurysm and particularly in patients currently smoking; alpha1-AT is very sensitive to oxidant agents. About 50% of physiological anti-oxidant systemic capacity is represented by Vitamin A, E and C. Plasmatic amounts of alpha1-AT, alpha1-AT Collagenase Inhibitory Capacity (CIC) and levels of vitamin A, vitamin E and vitamin C were analyzed in 39 patients, 26 women and 13 men, operated for intracranial aneurysm; 11 patients with unruptured intracranial aneurysm were considered as controls while 28 patients were included within 12 hours from subarachnoid hemorrhage (SAH). Plasmatic levels of vitamin A and vitamin E were significantly lower (p=0.038 and p=0.0158) in patients suffering SAH than in controls, while no statistically significant differences were found in mean plasmatic vitamin C levels. Level of alpha1-AT was not statistically different in controls and in patients with SAH; however, the activity of alpha1-AT, evaluated as CIC, is significantly reduced in patients with SAH (p=0.019). We have observed that systemic plasmatic levels of vitamins did not significantly differ in relation to smoking habit. Vitamin A and E represent an important defensive system against free radicals reactions. Particularly, vitamin E acts as an antioxidant by scavenging free-radicals. A reduced anti-oxidant status might be related to the higher sensibility of alpha1-AT to oxidative reactions and the activity of alpha1-AT is dependent on the antioxidant capacity of liposoluble vitamins. We can speculate that an acute systemic oxidative stress condition might influence the rupture of intracranial aneurysms.