Effect of two different parts of CGF on post-extractive alveolar ridge preservation: a preliminary histomorphometric analysis in a Split-Mouth design.

Tooth extraction produces alveolar bone resorption and soft tissue remodelling, so identification of adequate technique for alveolar ridge preservation after tooth extraction is fundamental for all specific cases. Among the several biomaterials, CGF can represent an ideal alternative considering its and its mechanical and biological properties. In this preliminary study we compared the effectiveness of the use of two different parts of CGF (WP-White Part and BC-Buffy Coat) versus natural healing (CTR) by a split-mouth randomized clinical design. Four healthy patients who needed extraction of three teeth were selected. Post-extractive alveolar sockets were filled randomly with CGF-WP, CGF-BC or nothing for CTR. After 60 days, before implant placement, a biopsy for each alveola was obtained for quantitative histomorphometric analysis. The data obtained showed that the use of CGF-WP could achieve good regenerative results, supporting the use of this part for the preservation of the post-extractive alveolar socket.

The myloglossus in a human cadaver study: common or uncommon anatomical structure?

BACKGROUND: Additional extrinsic muscles of the tongue are reported in literature and one of them is the myloglossus muscle (MGM). Since MGM is nowadays considered as anatomical variant, the aim of this study is to clarify some open questions by evaluating and describing the myloglossal anatomy (including both MGM and its ligamentous counterpart) during human cadaver dissections. MATERIALS AND METHODS: Twenty-one regions (including masticator space, sublingual space and adjacent areas) were dissected and the presence and appearance of myloglossus were considered, together with its proximal and distal insertions, vascularisation and innervation. RESULTS: The myloglossus was present in 61.9% of cases with muscular, ligamentous or mixed appearance and either bony or muscular insertion. Facial artery provided myloglossal vascularisation in the 84.62% and lingual artery in the 15.38%; innervation was granted by the trigeminal system (buccal nerve and mylohyoid nerve), sometimes (46.15%) with hypoglossal component. CONCLUSIONS: These data suggest us to not consider myloglossus as a rare anatomical variant.

Symmetrical anatomical variant of the anterior belly of the digastric muscle: clinical implicat.

The digastric muscle is an important surgical landmark. Several anatomical variants of the digastric muscle are reported in literature and, in particular, the presence of accessory anterior bellies of the muscle is not uncommon. Here, an unreported symmetrical variant of the digastric muscle was found during a dissection of the suprahyoid region. The dissection showed digastric muscles with an accessory anterior belly, which originated from the anterior belly of muscles in proximity and anteriorly to the intermediate tendon. The accessory bellies were fused together on the midline and were attached with a unique tendon to the inner surface of the mental symphysis. These muscles completely filled the submental triangle. This unreported anatomical variant could be considered an additional contribution to description of the anatomical variants of the digastric muscle, with several implications in head and neck pathology, diagnosis and surgery.

Attenuation of ultraviolet A-induced alterations in NIH3T3 dermal fibroblasts by melatonin.

BACKGROUND: Sun exposure is responsible for long-term clinical skin changes such as photoageing, photodamage and photocancers. Ultraviolet (UV)A wavelengths stimulate the production of reactive oxygen species (ROS) that may contribute to photoageing. To protect against oxidative stress, skin cells have developed several defence systems, including ROS and metal ion scavengers and a battery of detoxifying, haem-degrading and repair enzymes. Melatonin's antioxidant activity is the result of three different but complementary actions: (i) a direct action due to its ability to act as a free radical scavenger; (ii) an indirect action that is a consequence of melatonin's ability to reduce free radical generation (radical avoidance); and (iii) its ability to upregulate antioxidant enzymes. OBJECTIVES: In this study, we focused our attention on the prevention of photodamage, choosing melatonin as an antioxidant agent. METHODS: In the present study we analysed the effects of pretreatment of murine fibroblasts cells (NIH3T3) with melatonin (1 mmol L(-1) ) followed by UVA irradiation (15 J cm(-2) ). Thereafter, changes in components of the extracellular matrix and in some antioxidant enzymes (inducible and constitutive haem oxygenase) were evaluated. RESULTS: We observed that UVA radiation caused altered expression of extracellular matrix proteins and induced the expression of inducible haem oxygenase. This increase was not sufficient to protect the cells from damage. Instead, melatonin pretreatment led to increased expression of haem-degrading enzymes and suppression of UVA-induced photodamage. CONCLUSIONS: These results suggest that melatonin, as a modifier of the dermatoendocrine system, may have utility in reducing the effects of skin ageing.

Apolipoprotein E deficiency and a mouse model of accelerated liver aging.

The liver is the central metabolic organ which regulates several key aspects of lipid metabolism. The liver changes with age leading to an impaired ability to respond to hepatic insults and an increased incidence of liver disease in the elderly. Apolipoprotein E (ApoE) null mice have proved to be a very popular model to study spontaneous atherosclerosis, but recently it has been demonstrated that in ApoE-/- mice liver there are enzymatic and structural alterations, normally linked to the age. The purpose of this study was to consider ApoE-/- mice as a model for oxidative stress induced hepatic disease and to clarify how ApoE inactivation accelerates the aging process and causes liver disease.We used ApoE null mice and control mice at different ages (6 weeks and 15 months).Liver morphological damage as well as proteins involved in oxidative stress and liver ageing were all analyzed.Our study showed that ApoE null mice develop important age-related changes including oxidative stress, pseudocapillarization, increased polyploidy, decreased hepatocyte number and increased nuclear size. Our findings provide evidence that hypercholesterolemic ApoE-/- mice are more likely to develop severe liver injury, suggesting that in addition to vascular disease, increased cholesterol products and oxidative stress may also play a role in accelerating the progression of aging in the liver.

Osteonecrosis of the jaws and bevacizumab therapy: a case report.

Bevacizumab is a humanized recombinant monoclonal antibody that blocks vascular endothelial growth factor (VEGF). Recently, its use has been related with osteneocrosis of the jaws (ONJ), a disease showing a histological pattern similar to bisphosphonate-related ONJ. The aim of this study is to describe an ONJ case-report following bevacizumab chemotherapy without bisphosphonate therapy. We monitored ONJ development associated with the use of bevacizumab in a 47-year-old male with primitive adenocarcinoma of the parotid gland. Our results could suggest a possible correlation between the eruption of the lower third molar tooth and ONJ development following bevacizumab therapy. Clinicians should be aware of the potential risk of bevacizumab-related ONJ complication; moreover, since there are no effective therapeutic protocols for ONJ treatment, it is very important that patients develop good oral hygiene habits and undergo regular dental status evaluation by dentists.

Role of apolipoprotein E in renal damage protection.

It is well-known that nephrotic syndrome and chronic renal failure are associated with lipid and lipoprotein abnormalities. For a long time, it has been thought that hyperlipidemia is a secondary and insignificant condition of these renal injuries. Recently, it has been shown that dyslipidaemia may contribute to the development and progression of chronic kidney disease. Apolipoprotein E (apoE) null mice are a very popular model for studying spontaneous hypercholesterolemia, but only limited data are available for the role of apolipoprotein E in kidney disease. The purpose of this study is to evaluate kidney disease in apolipoprotein E deficient mice. For this study, apoE null mice and control mice at different ages (6 weeks and 15 months) were used. Kidney morphological damage and proteins involved in oxidative stress and aging (TNF-α and NF-kB) were analyzed. ApoE deficient mice have morphological alterations that are the hallmark of kidney pathogenesis, which increase with the age of the animals. In apoE null mice kidneys, there is also increased oxidative stress as compared to control mice at the same age and fewer antioxidant enzymes. Our findings add to the growing list of protective effects that apoE possesses.

Beneficial effects of melatonin on nicotine-induced vasculopathy.

Tobacco smoking is responsible for death of many people each year and increases the risk of developing numerous disorders, particularly cardiovascular disease and cancer. Among the components of cigarette smoke, nicotine is known to excert proatherosclerotic, prothrombotic and proangiogenic effects on vascular endothelial cells. The current study was designed to investigate the mechanisms by which nicotine induces endothelial dysfunction and further to examine whether melatonin protects against nicotine-induced vasculopathy. Four groups of male rats (controls, melatonin-treated, nicotine treated [100 microg/mL in drinking water], and nicotine plus melatonin [5 mg/kg/day] treated) were used in this study. After 28 days all the animals were killed by decapitation and the aorta was removed. We evaluated the hydroxyproline content, and the different expression of proteins involved in several types of stress (ERK1/2), in fibrosis (TGF-beta1, NF-kappaB) and in recruitment of circulating leukocytes onto the vessel wall, including intercellular adhesion molecule-1 (ICAM-1) and vascular cellular adhesion molecule-1 (VCAM-1). These metabolic pathways are important in the development of nicotine-induced atherosclerosis and hypertension. Our results show that nicotine induces marked structural and functional alterations in the aorta. Nicotine receptor binding results in activation and phosphorylation of ERK 1/2. This enzyme, in turn, activates both TGF-beta1 and NF-kappaB; they stimulate respectively the synthesis of type I collagen, responsible of fibrosis, and moreover ICAM-1, VCAM-1 and reactive oxygen species. Based on these findings, melatonin is able to minimize the negative effects of nicotine by blocking the activation of ERK and the other signalling pathways in which this enzyme is involved.

Intraosseous anastomosis in the maxillary sinus.

AIM: During sinus-lift surgery, certain intra-osseous vessels may be accidentally cut and this cause bleeding complications in approximately 20% of osteotomies. Therefore, understanding vascular details of the maxilla is very important for the surgeon. Here, we have given an anatomical overview of maxillary sinus vascularization through anatomical dissection. We have analyzed the distribution, localization and distance from the alveolar ridge of intraosseous branches of the maxillary artery found during sinus lift surgery. METHODS: Fifty-six maxillary bone doors were made bilaterally in twenty-eight unfixed cadavers; the doors were made between the first molar and the second molar (24 doors) or between the first and the second premolar (32 doors). RESULTS: Intraosseous arteries were found in 37 maxillary bones (66%). The average height of the artery from the alveolar crest was 13+/-3.2 mm in the distal doors and 18 +/- 6.1 mm in the mesial doors. Generally, the intraosseous maxillary branches ran caudo-rostrally; but in five maxillae, we found two parallel arteries, while in three cases the maxillary artery ran vertically. No differences were found between the left and right side. CONCLUSION: The risk of vascular damage in sinus floor elevation surgery is a real problem for the oral surgeon. Detailed anatomical knowledge about sinus vascularization is very important to reduce the risk of vascular damage and bleeding. In addition the visualization of sinus anastomosis by radiology and less invasive surgery, such as piezo-surgery, could be helpful.

In vitro effects of concentrated growth factors (CGF) on human SH-SY5Y neuronal cells.

OBJECTIVE: The aim of this study was to test the in vitro differentiation effects of concentrated growth factors (CGF), a platelet rich preparation, using SH-SY5Y cells, derived from human neuroblastoma. MATERIALS AND METHODS: SH-SY5Y cells were cultured in presence of CGF or retinoic acid (RA). After 72 h of treatment, different parameters were investigated: cell proliferation by an automated cell counter; cell viability by thiazolyl blue tetrazolium bromide (MTT) assay; cell differentiation markers, i.e., neuronal nuclear antigen (NeuN), synaptophysin (SYP) and ß3-tubulin, by immunocytochemistry and Western blotting techniques; release of nerve growth factor (NGF) and brain-derived growth factor (BDNF) by enzyme-linked immunosorbent assay (ELISA) and neurite outgrowth by a dedicated image software. RESULTS: In presence of CGF, the cell proliferation rate and viability decreased, as expected for differentiated SH-SY5Y cells. On the contrary, the cellular differentiation markers increased their expression together with the release of growth factors. Moreover, the neurite outgrowth was improved. CONCLUSIONS: The data suggest that CGF treatment positively affects the cell differentiation, regulating the expression of neuronal markers, the release of growth factors and the neurite length. Taken together these results seem to be promising in the development of new approaches for neural regeneration.

Role of caveolar compartmentation in endothelium-derived hyperpolarizing factor-mediated relaxation: Ca2+ signals and gap junction function are regulated by caveolin in endothelial cells.

BACKGROUND: In endothelial cells, caveolin-1, the structural protein of caveolae, acts as a scaffolding protein to cluster lipids and signaling molecules within caveolae and, in some instances, regulates the activity of proteins targeted to caveolae. Specifically, different putative mediators of the endothelium-derived hyperpolarizing factor (EDHF)-mediated relaxation are located in caveolae and/or regulated by the structural protein caveolin-1, such as potassium channels, calcium regulatory proteins, and connexin 43, a molecular component of gap junctions. METHODS AND RESULTS: Comparing relaxation in vessels from caveolin-1 knockout mice and their wild-type littermates, we observed a complete absence of EDHF-mediated vasodilation in isolated mesenteric arteries from caveolin-1 knockout mice. The absence of caveolin-1 is associated with an impairment of calcium homeostasis in endothelial cells, notably, a decreased activity of Ca2+-permeable TRPV4 cation channels that participate in nitric oxide- and EDHF-mediated relaxation. Moreover, morphological characterization of caveolin-1 knockout and wild-type arteries showed fewer gap junctions in vessels from knockout animals associated with a lower expression of connexins 37, 40, and 43 and altered myoendothelial communication. Finally, we showed that TRPV4 channels and connexins colocalize with caveolin-1 in the caveolar compartment of the plasma membrane. CONCLUSIONS: We demonstrated that expression of caveolin-1 is required for EDHF-related relaxation by modulating membrane location and activity of TRPV4 channels and connexins, which are both implicated at different steps in the EDHF-signaling pathway.

PPADS, a purinergic antagonist reduces Fos expression at spinal cord level in a mouse model of mononeuropathy.

Recent evidence suggest that ATP plays a role as an endogenous pain mediator generating and/or modulating pain signaling from the periphery to the spinal cord. In this study we evaluated the effects of intraperitoneal administration of P2 receptor antagonist, pyridoxalphosphate-6-azophenyl-2',4'-disulphonic acid (PPADS), evaluating pain related behaviours and monitoring the expression of Fos, a marker of activated neurons, in an experimental mouse model of neuropathic pain (sciatic nerve tying). The PPADS administration decreased both tactile allodynia and thermal hyperalgesia in a time and dose dependent manner. The dose of 25 mg/kg PPADS completely reversed nociceptive hypersensitivity. Moreover, non-noxious stimulation induced an increase of Fos positive neurons in the spinal cord of animals with tying of sciatic nerve. PPADS administration partially reversed this increase. These results suggest that PPADS reduces neuronal activation at spinal cord level and that P2 receptors are involved in the retrograde signalling progress exciting sensory spinal neurons.

Role of carbon monoxide and biliverdin in renal ischemia/reperfusion injury.

Heme oxygenase (HO) isoforms catalyze the conversion of heme to carbon monoxide (CO) and biliverdin/bilirubin with a concurrent release of iron. There is strong evidence that HO activity and products play a major role in renoprotection, however the exact molecular mechanisms underlying the beneficial effects exerted by this pathway are not fully understood. This review is aimed at illustrating the possible mechanism/s by which HO is renoprotective in the context of ischemia/reperfusion. We will first analyze the effects of exogenous administration of bilirubin/biliverdin and CO and then describe their biological activities once generated endogenously following stimulation of the HO pathway by either pharmacological means or gene targeting-mediated approaches.

Melatonin reduces excitotoxic blood-brain barrier breakdown in neonatal rats.

The blood-brain barrier (BBB) is a complex structure that protects the central nervous system from peripheral insults. Understanding the molecular basis of BBB function and dysfunction holds significant potential for future strategies to prevent and treat neurological damage. The aim of our study was (1) to investigate BBB alterations following excitotoxicity and (2) to test the protective properties of melatonin. Ibotenate, a glutamate analog, was injected intracerebrally in postnatal day 5 (P5) rat pups to mimic excitotoxic injury. Animals were than randomly divided into two groups, one receiving intraperitoneal (i.p.) melatonin injections (5mg/kg), and the other phosphate buffer saline (PBS) injections. Pups were sacrificed 2, 4 and 18 h after ibotenate injection. We determined lesion size at 5 days by histology, the location and organization of tight junction (TJ) proteins by immunohistochemical studies, and BBB leakage by dextran extravasation. Expression levels of BBB genes (TJs, efflux transporters and detoxification enzymes) were determined in the cortex and choroid plexus by quantitative PCR. Dextran extravasation was seen 2h after the insult, suggesting a rapid BBB breakdown that was resolved by 4h. Extravasation was significantly reduced in melatonin-treated pups. Gene expression and immunohistochemical assays showed dynamic BBB modifications during the first 4h, partially prevented by melatonin. Lesion-size measurements confirmed white matter neuroprotection by melatonin. Our study is the first to evaluate BBB structure and function at a very early time point following excitotoxicity in neonates. Melatonin neuroprotects by preventing TJ modifications and BBB disruption at this early phase, before its previously demonstrated anti-inflammatory, antioxidant and axonal regrowth-promoting effects.

A review of the effects of dietary silicon intake on bone homeostasis and regeneration.

OBJECTIVE: Increasing evidences suggest that dietary Silicon (Si) intake, is positively correlated with bone homeostasis and regeneration, representing a potential and valid support for the prevention and improvement of bone diseases, like osteoporosis. This review, aims to provide the state of art of the studies performed until today, in order to investigate and clarify the beneficial properties and effects of silicates, on bone metabolism. METHODS: We conducted a systematic literature search up to March 2013, using two medical databases (Pubmed and the Cochrane Library), to review the studies about Si consumption and bone metabolism. RESULTS: We found 45 articles, but 38 were specifically focused on Si studies. CONCLUSION: RESULTS showed a positive relationship between dietary Si intake and bone regeneration.

Controlling the activation of the Bv8/prokineticin system reduces neuroinflammation and abolishes thermal and tactile hyperalgesia in neuropathic animals.

BACKGROUND AND PURPOSE: Chemokines are involved in neuroinflammation and contribute to chronic pain processing. The new chemokine prokineticin 2 (PROK2) and its receptors (PKR1 and PKR2 ) have a role in inflammatory pain and immunomodulation. In the present study, we investigated the involvement of PROK2 and its receptors in neuropathic pain. EXPERIMENTAL APPROACH: Effects of single, intrathecal, perineural and s.c. injections of the PKR antagonist PC1, or of 1 week s.c. treatment, on thermal hyperalgesia and tactile allodynia was evaluated in mice with chronic constriction of the sciatic nerve (CCI). Expression and localization of PROK2 and of its receptors at peripheral and central level was evaluated 10 days after CCI, following treatment for 1 week with saline or PC1. IL-1ß and IL-10 levels, along with glia activation, were evaluated. KEY RESULTS: Subcutaneous, intrathecal and perineural PC1 acutely abolished the CCI-induced hyperalgesia and allodynia. At 10 days after CCI, PROK2 and its receptor PKR2 were up-regulated in nociceptors, in Schwann cells and in activated astrocytes of the spinal cord. Therapeutic treatment with PC1 (s.c., 1 week) alleviated established thermal hyperalgesia and allodynia, reduced the injury-induced overexpression of PROK2, significantly blunted nerve injury-induced microgliosis and astrocyte activation in the spinal cord and restored the physiological levels of proinflammatory and anti-inflammatory cytokines in periphery and in spinal cord. CONCLUSION AND IMPLICATIONS: The prokineticin system contributes to pain modulation via neuron-glia interaction. Sustained inhibition of the prokineticin system, at peripheral or central levels, blocked both pain symptoms and some events underlying disease progression.

SPECT analysis of a new implant surface: a human preliminary report.

AIM: Several recent medical reports have focused attention on the possible application of skeletal scintigraphy imaging in odontostomatology. The aim of the present report was to assess the influence of a new implant surface on peri-implant osteoblastic activity through bone scintigraphy. METHODS: Implants were placed in one healthy subject. A nuclear medicine investigation with single-photon emission-computed tomography (SPECT) was performed at 30 and 90 days after implant placement. The study was completed with acquisition of planar images of the skull in an anterior view and the use of regions of interest (ROIs) of the same size in the area corresponding to new surfaces implants and in the opposite maxilla (at the control sites). Count density ratios (counts/pixel) obtained from each ROI were used for a quantitative/relative assessment. Tomographic images were evaluated with a qualitative method. RESULTS: Routine planar methodology provided a direct measure of cellular activity of the examined areas. The difference in count density ratio registered from the same ROI between the first and the second scintigraphy revealed the course of peri-implant osteoblastic activity, which was very high in the first month and then declined during subsequent months. CONCLUSIONS: In spite of the small number of involved patients, the results obtained from this pilot study suggest that nuclear medicine investigation held advantages in oral implantology to clarify those aspects still unknown dealing with osteoblastic activity.

Reduction of precocious peri-implant resorption cone.

AIM: After implant-insertion, bone tissue, newly-formed on peri-implant crest, undergoes to a mild marginal osseous readjustment due to build-up of inflammatory cell tissue (ICT). The present study verifies the possibility to limit bone resorption by placing implant fixtures 0.5 mm outside cortical bone edge. METHODS: A clinically-controlled randomized study on 100 implants has been performed to compare early resorption process of implant fixtures placed 0.5 mm outside cortical bone edge with implant-fixtures inserted according to juxtacortical bone conventional protocols. RESULTS: After 6 months, bone implant level was higher with emersion approach (-1.01±0.54 mm, mean±SD) than with submerged treatment (-1.56±0.5 mm) (P<0.001). CONCLUSIONS: Factors to achieve an excellent result at mean-long term seem to be very good, even though the latter have to be confirmed by follow-up.

Evaluation of quality of life in patients with total or partial edentulism treated with computer-assisted implantology.

AIM: The study deals with a preliminary analysis that compares quality of life of a randomized sample of patients with total or partial edentulism rehabilitated through conventional implantology or computer-assisted implantology. METHODS: The first group was treated with conventional implantology, while the second group was treated with NobelGuide™ computer-assisted implantology. every patient has filled up a questionnaire about quality of life in presurgical period (sf-361), in postsurgical period (sf-361; tiq2) and about the gratification after prosthetic treatment. the questionnaire has evaluated physical, general and psycho-emotive health parameter. RESULTS: SF-36 has demonstrated an improvement in quality of life after computer-assisted surgery. tiq has revealed that patients symptoms in post-surgical week were inferior in quality and in quantity in NobelGuide™ technique. gratification questionnaire has demonstrated that quality of life improvement matches patient full satisfaction after the treatment. CONCLUSIONS: NobelGuide™ protocol improves physical health after implantology with positive reflections on psycho-emotive health. furthermore prefabricated temporary prostheses reduces treatment time and patient discomfort.

A review of the mandibular and maxillary nerve supplies and their clinical relevance.

Mandibular and maxillary nerve supplies are described in most anatomy textbooks. Nevertheless, several anatomical variations can be found and some of them are clinically relevant. Several studies have described the anatomical variations of the branching pattern of the trigeminal nerve in great detail. The aim of this review is to collect data from the literature and gives a detailed description of the innervation of the mandible and maxilla. We carried out a search of studies published in PubMed up to 2011, including clinical, anatomical and radiological studies. This paper gives an overview of the main anatomical variations of the maxillary and mandibular nerve supplies, describing the anatomical variations that should be considered by the clinicians to understand pathological situations better and to avoid complications associated with anaesthesia and surgical procedures.