Air pollution/working activity correlation: a case study in a dental hospital.

The paper deals with a multidimensional approach demonstrating a direct link between the entity of ongoing dentistry activity (number and kind of interventions) and specific pollution components. Simultaneously indoor/outdoor air concentrations of a set of volatile organic compounds (VOCs) and activity variables, describing the amount and nature of ongoing dentistry activities, were monitored over a year at a dental hospital located in an urban area. Principal Component Analysis (PCA) was used to single out mutually orthogonal pollution components which were then correlated to "pathology" factors arising from the analysis of dentistry activity indexes. The use of a multidimensional perspective allowed us to obtain a statistically significant model of the link between level of pollution and dentistry activity. In particular, the correlation approach linking pollution results to pathological variables allows us to establish a causative link even in the presence of sub-threshold concentrations of pollutants.

Basal cell adenoma with S-100 positive stroma: a case report and literature review.

Basal cell adenoma (BCA) of the salivary gland with presence of abundant S-100-positive stromal cells has been rarely reported. A case occurring in a 75-year-old man is presented here, as well as a review of the literature on the subject. The patient presented with a nodule in the right parotid gland. In addition to the typical features of BCA, histologically the resected tumor showed a substantial amount of stroma rich in S-100-positive spindle cells, a rarely reported finding in BCA. These cells were unreactive with a panel of myoepithelial markers, including calponin, p63, muscle-specific actin (MSA), smooth muscle actin (SMA), cytokeratin 14 (CK14), and glial fibrillary acidic protein (GFAP). Our results, in accordance with other reports, do not support a myoepithelial nature of these S-100-positive cells, and their precise nature remains elusive.

Mechanical qualification of collagen membranes used in dentistry.

AIM: The aim of this work is the qualification of commercially available collagen membranes in a comparative manner. The natural origin of collagen makes standardization difficult. Nevertheless, through dimensional and mechanical measures it is possible to mechanically qualify collagen membranes, and compare them. METHODS: Three commercially available collagen membranes used in Guided Bone Regeneration (GBR) and in Guided Tissue Regeneration (GTR) techniques, namely Bio-Gide, Collprotect and Jason, were chosen for the comparison. Quasi-static (tensile tests) and time-dependent (stress relaxation test) mechanical tests together with a functional test (tear test) were done to determine the responses of collagen membranes under different loading conditions. RESULTS: The tested membranes exhibited different behaviours, different deformability values and thickness, Jason being the thinnest and Bio-Gide the thickest. Similar differences were also observed in terms of surface density. DISCUSSION: Even though clinical observations were not within the aim of this study, our findings indicate that a better understanding of the correlation between mechanical properties and thickness could lead to a more rational design and use of these membranes in the face of specific clinical cases.

Chlamydia pneumoniae Clinical Isolate from Gingival Crevicular Fluid: A Potential Atherogenic Strain.

Chlamydia pneumoniae has been associated to atherosclerotic cardiovascular diseases. The aim of our study was to characterize, for the first time, a C. pneumoniae strain isolated from the gingival crevicular fluid of a patient with chronic periodontitis, described as a risk factor for cardiovascular diseases. C. pneumoniae isolate was characterized and compared to the respiratory AR-39 strain by VD4-ompA genotyping and by investigating the intracellular growth in epithelial and macrophage cell lines and its ability to induce macrophage-derived foam cells. Inflammatory cytokine levels were determined in the gingival crevicular fluid sample. C. pneumoniae isolate showed a 99% similarity with the AR-39 strain in the VD4-ompA gene sequence and shared a comparable growth kinetic in epithelial cells and macrophages, as evidenced by the infectious progeny and by the number of chlamydial genomic copies. C. pneumoniae isolate significantly increased the number of foam cells as compared to uninfected and LDL-treated macrophages (45 vs. 6%, P = 0.0065) and to the AR-39 strain (45 vs. 30%, P = 0.0065). Significantly increased levels of interleukin 1-ß (2.1 ± 0.3 pg/µL) and interleukin 6 (0.6 ± 0.08 pg/µL) were found. Our results suggest that C. pneumoniae may harbor inside oral cavity and potentially be atherogenic, even though further studies will be needed to clarify the involvement of C. pneumoniae in chronic periodontitis as a risk factor for cardiovascular diseases.

Effect of PDGF, IGF-1 and PRP on the implant osseointegration. An histological and immunohistochemical study in rabbits.

The ability of platelet-derived growth factor (PDGF), insulin-like growth factor-1 (IGF-1) and platelet-rich plasma (PRP) to increase the rate of osseointegration of endosseous implants and to improve the quality of bone remodeling on the surface of titanium, has been investigated in an experimental intraosseous defect model by an histological and immunohistochemical evaluation. The results from this study demonstrate that rabbits treated with the combination PDGF/IGF-1 showed a higher positive effect on bone regeneration than PRP-treated or controls.

Cephalometric pattern and nasal patency in children with primary snoring: the evidence of a direct correlation.

INTRODUCTION: Sleep disordered breathing (SDB) might affect craniofacial growth and children with obstructive sleep apnea syndrome present an increase in total and lower anterior heights of the face and a more anterior and inferior position of the hyoid bone when compared to nasal breathers. OBJECTIVE: To investigate the correlation between rhinomanometric and cephalometric parameters in children with primary snoring (PS), without apnea or gas exchange abnormalities. MATERIALS AND METHODS: Thirty children with habitual snoring (16 females and 14 males) aged 4-8 years (mean age 6.85±1.51 years) were selected by a SDB validate questionnaire. All subjects underwent lateral cephalometric, panoramic radiographies. RESULTS: In our sample 10 children (33%) had snoring 3 nights/week, 11 (37%) 4-6 nights/week and 9 (30%) every night/week. Overall 7 patients (23.3%) were affected by adenoid hypertrophy (AH), 4 (13.3%) by tonsillar hypertrophy (TH) and 13 (43.3%) by AH and TH. We found a more vertical position of the hyoid bone to the mandibular plane (H⊥VT) in patients with a higher frequency (7.3±2.7 vs 7.6±3.7 vs 10.9±2.5 in children snoring 3 nights/week, 4-6 nights/week and every night/week respectively; p = 0.032). Concerning nasal patency significant correlations were found with ANB (maxillary and jaw position with respect to the cranial base), NS∧Ar (growth predictor), sumangle, FMA (total divergence), SnaSnp∧GoMe (inferior divergence), BaN∧PtGn (facial growth pattern), Phw1_PsP (posterosuperior airway space), AHC3H (the horizontal distance between the most anterosuperior point of the hyoid bone and the third cervical vertebra). CONCLUSION: The present study supports the relationship between nasal obstruction and specific craniofacial characteristics in children with primary snoring and lead us to hypothesize that nasal obstruction might explain the indirect link between snoring and cephalometric alterations.

Investigation of indoor air volatile organic compounds concentration levels in dental settings and some related methodological issues.

The assessment of indoor air volatile organic compounds (VOCs) concentration levels in dental settings has a big health relevance for the potentially massive occupational exposure to a lot of diverse contaminants. The comparison of the VOCs profile relative to indoor conditions and to the corresponding outdoor concentrations, as well as the discovery of possible correlations between specific dental activities and VOCs concentration variations are of utmost importance for offering a reliable characterization of risk for dentists and dental staff health. In this study we review the most relevant environmental studies addressing the VOCs contamination level in dental settings. We analyze the methodological problems this kind of study must face and we report preliminary results of an indoor air investigation, carried out at dental hospital in Italy, the "Ospedale odontoiatrico George Eastman" of Rome, in which general lines for the analysis of dental settings in environmental terms are sketched. The aim of this work is to identify the kind of problems a typical enclosed (non-industrial) environment indoor air investigation has to cope with by means of the analysis of a case study.