Surface Ocean Biogeochemistry Regulates the Impact of Anthropogenic Aerosol Fe Deposition on the Cycling of Iron and Iron Isotopes in the North Pacific.

Distinctively-light isotopic signatures associated with Fe released from anthropogenic activity have been used to trace basin-scale impacts. However, this approach is complicated by the way Fe cycle processes modulate oceanic dissolved Fe (dFe) signatures (δ56Fediss) post deposition. Here we include dust, wildfire, and anthropogenic aerosol Fe deposition in a global ocean biogeochemical model with active Fe isotope cycling, to quantify how anthropogenic Fe impacts surface ocean dFe and δ56Fediss. Using the North Pacific as a natural laboratory, the response of dFe, δ56Fediss, and primary productivity are spatially and seasonally variable and do not simply follow the footprint of atmospheric deposition. Instead, the effect of anthropogenic Fe is regulated by the biogeochemical regime, specifically the degree of Fe limitation and rates of primary production. Overall, we find that while δ56Fediss does trace anthropogenic input, the response is muted by fractionation during phytoplankton uptake, but amplified by other isotopically-light Fe sources.

Constraints on the Cycling of Iron Isotopes From a Global Ocean Model.

Although iron (Fe) is a key regulator of primary production over much of the ocean, many components of the marine iron cycle are poorly constrained, which undermines our understanding of climate change impacts. In recent years, a growing number of studies (often part of GEOTRACES) have used Fe isotopic signatures (δ56Fe) to disentangle different aspects of the marine Fe cycle. Characteristic δ56Fe endmembers of external sources and assumed isotopic fractionation during biological Fe uptake or recycling have been used to estimate relative source contributions and investigate internal transformations, respectively. However, different external sources and fractionation processes often overlap and act simultaneously, complicating the interpretation of oceanic Fe isotope observations. Here we investigate the driving forces behind the marine dissolved Fe isotopic signature (δ56Fediss) distribution by incorporating Fe isotopes into the global ocean biogeochemical model PISCES. We find that distinct external source endmembers acting alongside fractionation during organic complexation and phytoplankton uptake are required to reproduce δ56Fediss observations along GEOTRACES transects. δ56Fediss distributions through the water column result from regional imbalances of remineralization and abiotic removal processes. They modify δ56Fediss directly and transfer surface ocean signals to the interior with opposing effects. Although attributing crustal compositions to sedimentary Fe sources in regions with low organic carbon fluxes improves our isotope model, δ56Fediss signals from hydrothermal or sediment sources cannot be reproduced accurately by simply adjusting δ56Fe endmember values. This highlights that additional processes must govern the exchange and/or speciation of Fe supplied by these sources to the ocean.

Primordial odontogenic tumour: A systematic review of the common but also unusual features of this novel entity.

BACKGROUND: Primordial odontogenic tumour (POT) is a novel entity that was described in 2014 and that is included in the group of benign mixed epithelial and mesenchymal odontogenic tumours. In recent years, several papers have added new cases with some clinical and histopathological aspects that slightly differ from those described in the original report. The aim of this systematic review is to update all available data on POT published in the literature and to identify those features of the neoplasm that require further investigation. MATERIALS AND METHODS: A systematic review of literature was conducted using PubMed, Embase, Web of Science and Scopus. Additional sources were also checked. Publications reporting cases with enough clinicopathological information were included, without any time or language restrictions. Histopathological or radiological studies were considered for qualitative analysis. RESULTS: A total of 30 publications were included. Seventeen papers were used for quantitative analysis while 13 papers were used only for qualitative analysis. A total of 18 cases of POT were identified. Some clinical, radiographic, histopathological and therapeutic features were common in all reported cases, while other aspects of the neoplasm were inconsistent through published cases. This inconsistency was particularly remarkable when dealing with the histopathological features of the neoplasm. DISCUSSION: Some issues about POT remain unclear and deserve to be clarified by future reports. The description of the odontogenic epithelium covering the ectomesenchyme is often contradictory, while it remains debatable whether peripheral ameloblastic epithelial islands or hard dental tissue deposition can occasionally occur within the tumour.

Clinical applications of Natural Bone Morphoproteins in dentistry: a narrative review.

The need to restore bone loss in maxilla and mandible has led to find natural bone substitutes, such as fresh autogenous bone grafts. Fresh autogenous bone grafts (FABGs) have a remarkable capacity to induce new bone formation, a phenomenon called ‘osteoinduction.’ FABGs are useful in craniomaxillofacial and oral applications to restore bone deficiencies. The isolation of those proteins believed to be responsible for the osteoinductive activity of FABGs, namely Natural Bone Morphogenetic Proteins (NBMPs), led to a new era in bone regeneration. NBMPs have been approved for use in specific oral and maxillofacial applications. Clinical trials and studies of oral and craniofacial surgery have indicated that NBMPs can promote bone repair. Information about the biology, chemistry, and actions of NBMPs has called into question whether NBMPs would result in clinically useful bone induction and morphogenesis. Preclinical and specific clinical trials have indicated the efficacy of NBMPs either combined with autograft or compared with an autograft alone. In light of questions about potency and safety of NBMPs, however, additional high-level evidence is needed for specific clinical indications and appropriate patient populations that would benefit from their use.

Prevalence of HIV-related oral manifestations and their association with HAART and CD4+ T cell count: a review.

HIV infection is one of the major health problem of the last decades. This disease causes a chronic infection that can lead to acquired immunodeficiency syndrome (AIDS). According to the Global AIDS update, released in 2016 by HIV department of World Health Organization (WHO) and by the Joint United Nations Program on HIV/AIDS (UNAIDS), at the end of 2015, 36.7 million people were infected by HIV: 34.9 million of these were adults and 1.8 million were children under 15 years of age. The same report shows that during 2015, 2.1 million of new infection cases have occurred all over the world and about 1.1 million people have died for HIV. The aim of this short review is to up-date of the main HIV-related oral manifestations and their correlation with HAART (Highly Active Antiretroviral Therapy) and CD4+ T-cell count. Despite that more than 20 years have elapsed, this classification still remains valid: even today, group 1 lesions are found in the majority of HIV-positive patients with oral manifestations. Group 1 includes the following conditions: oral candidiasis (pseudomembranous candidiasis, erythematous candidiasis, angle cheilitis), oral hairy leukoplakia, periodontal diseases (necrotizing gingivitis, necrotizing periodontitis, linear gingival erythema), Kaposi’s sarcoma, and non-Hodgkin’s lymphoma. Melanotic hyperpigmentation, HSV infection and HPV infection, which are included in group 2, are also common. Oral candidiasis, oral hairy leukoplakia, Kaposi’s sarcoma and HSV infection are the lesions that have seen the major drop in their incidence after the HAART introduction. The increase in CD4+ T-cell count is not significantly correlated to the decrease of every type of oral lesions, but it is statistically significant only in relation to oral candidiasis (p-value less than 0.001). Oral lesions are an important sign of immunodepression and with the introduction of HAART their incidence has strongly decreased, particularly in urban areas. Nevertheless, developing countries still have a high prevalence of these manifestations because of the persistence of many risk factors, like the difficulty to access treatment, poor oral hygiene, low socioeconomic status and late diagnosis.

New insights in orofacial cleft: epidemiological and genetic studies on italian samples.

Cleft of the lip and/or palate (CL±P) is the most common congenital craniofacial anomaly affecting around 1 in 700 live births worldwide. Clefts of the human face can be classified anatomically as cleft lip only (CL), cleft palate only (CP), cleft lip and palate (CLP) or a combined group of cleft lip with or without cleft palate (CL±P), based on differences in embryologic development. CL±P has a genetic base and several linkage and association analyses have been performed in order to obtain important information about the role of candidate genes in its onset; not less important are gene-environment interactions that play an increasing role in its aetiology. In CL±P, several loci have been seen associated with the malformation, and, in some cases, a specific gene mapping in a locus has also been identified as susceptibility factor. In CP, one gene has been found, but many more are probably involved. In this short review the genetic studies carried out on CL±P, and the interaction with environmental factors (alcohol, smoking, drugs) are discussed.

Genetic susceptibility and periodontal disease: a retrospective study on a large italian sample.

BACKGROUND: Periodontal disease (PD) is a multifactorial illness in which environment and host interact. The genetic component plays a key role in the onset of PD. In fact the genetic compound can modulate the inflammation of the mucous membranes and the loss of alveolar bone. The genetics of PD is not well understood. Previous studies suggest a strong association between PD occurrence and individual genetic profile. The role of genetic susceptibility could impact on the clinical manifestations of PD, and consequently on prevention and therapy. MATERIALS AND METHODS: Genetic polymorphisms of VRD, IL6 and IL10 were investigated in Italian adults affected by PD. 571 cases classified according the criteria of the American Academy of Periodontology were included. All patients were Italian coming from three areas according to italian institute of statistics (ISTAT) (www.istat.it/it/archivio/regioni). The sample comprised 379 patients from North (66%), 152 from Central (26%) and 40 of South (8%). RESULTS: No significant differences were found among allele distribution. CONCLUSION: Chronic PD is a complex disease caused by a combination of genetic susceptibility, patients habits (oral hygiene, smoking, alcohol consumption) and oral pathogens. In our report no differences were detected among three Italian regions in allele distribution.

Cleft palate only: current concepts.

Cleft palate only (CPO) is one of the most common congenital malformations worldwide. The etiopathogenesis of CPO is not completely understood. Environmental factors, such as smoking, alcohol consumption, intake of drugs during pregnancy, advanced paternal age, have been demonstrated to be a risk of CPO, but conflicting results have also been published. Insufficient intake of folic acid during the pregnancy has been suggested to increase the risk for CPO. The demonstrated risk for siblings and the higher risk for monozygotic twins suggest a genetic etiopathogenesis for CPO. In some cases of CPO a prevalent mode of inheritance has been reported, but oligogenic models with reduced penetrance, and the risk related to environmental factors have also been proved. One of the first manifestations associated with CPO is difficulty with feeding. Aerophagia is a problem in these infants with CPO and requires more frequent burping and slower feeding. The inability to generate intraoral breath pressure due to nasal air emission in CPO children frequently manifests as articulation difficulties, particularly consonant weakness, and unintelligible speech. Hearing disorders are prevalent among individuals with CPO, as a result of chronic otitis media with effusion due to eustachian tube dysfunction. A multidisciplinary team is essential to manage the many aspects of CPO. In treating CPO, the reconstructive surgeon works in cooperation with otolaryngologists, dentists and orthodontists, speech pathologists, audiologists, geneticists, psychiatrists, maxillofacial surgeons, social workers, and prosthodontists. CPO can be considered a genetically complex disease, but new knowledge and new therapeutic approaches have greatly improved the quality of life of these children. Prenatal diagnosis is an important step in the treatment of this disease.

ADULT syndrome: dental features of a very rare condition.

The Acro-Dermato-Ungual-Lacrimal-Tooth syndrome (ADULT syndrome) is one of the rarest ectodermal dysplasias and it is associated with several malformations involving especially the limbs. The most clinical features are the presence of ectrodactyly, syndactyly, hypermelanosis or multiple lentigines, onhycodysplasia, abnormalities in the lacrimal duct, recurrent conjuntivitis, photophobia, mammarian hypoplasia, hypotrichosis and frontal alopecia, hypohydrosis, cutaneous photosensitivity, nasal bridge prominence, exfoliative dermatitis and xerosis. The ectodermal dysfunction expresses itself with conoid teeth, enamel hypoplasia, dentinal dysplasia and especially hypodontia, with following functional and aesthetic defects. We report the case of an 11-year-old Caucasian girl affected by ADULT syndrome.

Vascular endothelial growth factor and nitric oxide synthase expression in human tooth germ development.

Vascular Endothelia Growth Factor (VEGF) and Nitric Oxide Synthase (NOS) expression, were evaluated in human tooth germs at two different stages of embryogenesis, to clarify the role of angiogenesis during tooth tissue differentiation and growth. Seventy-two third molar germ specimens were selected during oral surgery. Thirty-six were in the early stage and 36 in the later stage of tooth development. The samples were evaluated with Semi-quantitative Reverse Transcription-Polymerase chain Reaction analyses (RT-PcR), Western blot analysis (WB) and immunohistochemical analysis. Western blot and immunohistochemical analysis showed a VEGF and NOS 1-2-3 positive reaction in all samples analysed. VEGF high positive decrease reaction was observed in stellate reticulum cells, ameloblast and odontoblast clusters in early stage compared to later stage of tooth germ development. Comparable VEGF expression was observed in endothelial cells of early and advanced stage growth. NOS1 and NOS3 expressions showed a high increased value in stellate reticulum cells, and ameloblast and odontoblast clusters in advanced stage compared to early stage of development. The absence or only moderate positive reaction of NOS2 was detected in all the different tissues. Positive NOS2 expression showed in advanced stage of tissue development compared to early stage. The action of VEGF and NOS molecules are important mediators of angiogenesis during dental tissue development. VEGF high positive expression in stellate reticulum cells in the early stage of tooth development compared to the later stage and the other cell types, suggests a critical role of the stellate reticulum during dental embryo-morphogenesis.

SURVIVAL RATES OF NARROW VERSUS STANDARD DIAMETER IMPLANTS IN DIFFERENT TREATMENT OPTIONS: A RETROSPECTIVE STUDY.

Implant dentistry has had a great success in the last decades for replacing missing teeth; however, implant surgery needs bone availability. The use of narrow diameter implants (NDIs) may be an alternative approach in patients with atrophic maxilla or mandible. The aim of this study is to perform a study on NDIs to evaluate their survival rate. In the period between January 2008 and December 2013, 877 patients (498 females and 379 males) were operated at the BDD private Practice Clinic (Milan, Italy). The mean post-surgical follow-up was 30±17 months (max – min, 84 – 1). One thousand three hundred and forty-six implants (EDIERRE Implant System SpA, Genoa, Italy) were included in the present study, 112 (8.3%) 3.3 mm (i.e. narrow) and 1,234 (91.7%) 3.75 mm wide. All patients underwent the same surgical protocol and agreed to participate in a post-operative check-up program. SPSS program was used for statistical analysis. Survival rate (SVR) was 97.25% since only 37 fixtures were lost from a total of 1,346 implants. Cross-tabulation between failure diameter did not demonstrate any statistical differences between narrow and standard diameter implants. NDIs are reliable devices for oral rehabilitation.

NONSURGICAL PERIODONTAL MANAGEMENT OF IATROGENIC PERI-IMPLANTITIS: A CLINICAL REPORT.

Dental implants have emerged as a first line of treatment to replace missing teeth for both the edentulous and partially dentate patients. The anticipated high degree of success is somewhat challenged by the onset of peri-implantitis. Peri-implant diseases are a cluster of “contemporary” oral infections in humans; they are characterized by the inflammatory destruction of the implant-supporting tissues, as a result of biofilm formation on the implant surface. It is still not clear how the roles of its etiologic agents work. A history of periodontitis, poor oral hygiene, and smoking are considered as risk factors for peri-implant diseases. Occasionally failing implants are associated with iatrogenic factors, that, only recently, have been acknowledged as direct cause of peri-implant complications, i.e.: non-parallel adjacent implants or the presence of a gap, between fixture and prosthetic components. The use both of traditional protocols of nonsurgical periodontal therapy and the diode laser seems to be an effective alternative treatment modality for peri-implantitis. By the application of laser-assisted non-surgical peri-implant therapy the periodontal pocket depth was reduced. Intraoral periapical radiographs, taken at 6 months and 1 year post nonsurgical treatment, seemed to provide evidence of some improvement of the bone level. The present article illustrates the nonsurgical management of one case, where failure to remove residual cement, from an implant-supported dental prosthesis, seemed to cause peri-implant inflammation.

Nitric oxide synthase evaluation in oral precancerous and cancerous lesions.

Nitric Oxide (NO) has been linked to several cardiovascular, neurological and immunological physiological and pathological functions. Several studies have shown that the eNOS, nNOS and iNOS effects on cancer cell growth and proliferation are related to the upregulation of the Wnt pathway and have a central role during metastasis development. Recent studies suggest that cancer cells undergo metabolic reprogramming, which drives cancer cell growth and progression. The aim of this study was to observe the NOS activity in the pathogenesis of oral precancerous and cancerous lesions. The results showed changes in eNOS activity levels, which increased from healthy oral mucosa to oral squamous cell carcinoma SCC, through different dysplasia levels. The iNOS activity levels increased in precancerous lesions compared to healthy mucosa, where iNOS was absent, while it decreased in SCC lesions. Moreover, a gradual increase of nNOS activity together with the progression of the lesions was also found. These results may suggest how NO could play a critical role during pathogenesis, growth and development of precancerous lesions to cancer degeneration.

Oral Squamous Cell Carcinoma in the paediatric patient: a literature review.

AIM: Paediatric Oral Squamous Cell Carcinoma (OSCC) is rare, but its incidence is increasing, bringing forward the issue of the common pathogenic factors. The aim of this study is to verify the actual incidence of oral carcinoma reported in paediatric patients up to the age of 15 by thoroughly reviewing the available literature. Setting this cut-off age has allowed us to emphasise possible risk factors other than those always associated with the onset of this neoplasia, which are not present in this age bracket yet. METHODS: In the first stage of the research, generic key words concerning OSCC in childhood were entered into two search engines. In the second stage, terms related to predisposing diseases connected to childhood oral carcinoma and those initially found were searched. RESULTS: The literature review consisted of 55 documented cases from 1894 to 2011, of which 15 were part of complete published case reports. CONCLUSION: Paediatric OSCC, though uncommon, is not rare. The review has strongly highlighted the need to carry out an objective, thorough and standardised examination of the child's oral cavity, especially when systemic predisposing diseases, such as Epidermolysis bullosa, Xeroderma pigmentosum, Juvenile papillomatosis and Fanconi's anaemia, are present.

Scanning electron microscopy evaluation of the link between a new dentinal desensitizer and dentine.

AIM: The purpose of this study was to evaluate the interaction of a novel dentinal desensitizer Twin Pro with enamel-dentinal adhesive preparations or filling materials and dentine using scanning electron microscopy (SEM) technology. METHODS: Black's I class cavities were drilled extracted molar teeth free of caries or fissures, and the cavities disinfected. The specimens were divided into 4 groups of 2 teeth each treated as follows: Group A: Twin Pro, fluid (Tetric-Flow Vivadent) and micro-hybrid (Tetric-Ceram Vivadent) composites placed on the etched (Liner Bond 2V Clearfil) cavities. Group B: Twin Pro, PQ1-Ultradent loaded Primer-Bonding plus fluid and micro-hybrid composites applied to the acid-etched (37% orthophosphoric acid) cavities. Group C: Twin Pro plus Silver amalgam alloy (Phasealloy- Sybram Kerr). Group D (control group): self-etching primer plus fluid and micro-hybrid composite. Specimens were investigated by SEM. RESULTS: The results obtained in all groups show that the application of Twin Pro does not alter the adhesiveness of the restorative composite materials to the dental wall. In fact the desensitizer and the adhesive layers are indistinguishable at SEM observation, and well adherent to the dentinal surface of the cavities. CONCLUSION: The results of SEM investigations show that Twin Pro does not decrease the adhesion of restorative materials to the tooth surface, as it establishes an efficient interconnection with the different materials used, and it forms a uniform layer covering and occluding dentine tubules, and this might constitute an efficacious sealing of dentinal tubules which possibly contribute to decrease dentinal sensitivity to environmental nociceptive stimuli.

Ureteral obstruction following allogeneic bone marrow transplantation in children.

Two patients with Ph + CML underwent URD-BMT after conditioning with Bu-Cy-LPAM. They developed hemorrhagic cystitis with an extremely complicated and painful course, caused by ureteral obstruction, requiring prolonged hospitalization. No virus other than cytomegalovirus was found and in both cases was attributed to Cy use. Treatment is usually conservative, but in the case of severe obstruction, a surgical approach should be considered and performed as early as possible to preserve renal function.

Mild pre-transplant cardiomyopathy may not impair long-term quality of life after bone marrow transplantation.

An 8-year-old child with acute myeloid leukemia (AML), underwent an allogeneic bone marrow transplant (BMT) from his HLA matched sister in spite of having a mild cardiomyopathy. We followed the patient with periodic electrocardiograms (ECG) and echocardiograms which have not worsened, and the patient's quality of life is not compromised 14 years after BMT. Bone Marrow Transplantation (2000) 25, 335-336.