Comparative ergonomic evaluation of the hand-pieces of three instrument series for root planning

Introduction: Musculoskeletal disorders (MSD) are the most frequent cause of disability in the working population, exceeding accidental trauma in frequency. The risk of developing work-related upper limb disorders (WURLDs) is high among dental hygienists and the most frequently affected are elderly subjects and women. Since such disorders can have a negative effect on the working life and on the quality of life, it is of vital importance to put in place preventive measures. Aim: To make a comparative analysis of the hand-pieces of three different manual instruments used for root planning. Materials and Methods: To evaluate the physical characteristics (section, diameter, external surface, weight) of the hand-pieces of three series of instruments for root planning, twentynine dental hygienists students were videoed while working clinically. They were also interviewed using a specific questionnaire to determine subjective preferences in terms of perceived efficacy, safety, comfort and general acceptability of the hand-piece used. Results: Lightness, full-cylindrical section with larger- diameter ends, and coating with anti-slip silicone are the most appreciated characteristics of a handpiece. Conclusions: Ergonomic analyses of manual instruments are not frequent in the dental field, and the literature reports no guidelines to guide selection of the type of hand-piece of manual instruments. The data gathered may help manufacturers in designing new manual instruments, and guiding professionals in their selection

The factors affecting visual discomfort of dental hygienist

partially_open4noThe objectives of the paper were to analyze the visual behavior and visual discomfort parameters of dental practitioner at work, introducing the “lighting quality” approach in professional lighting using a suitable measurement methodology able to evaluate all relevant photometric and spectral parameters, not only the standard expected, and also the luminance map of the visual field. Spectral investigations are necessary to evaluate the damage potential of the lighting radiation while the luminance map allows the evaluation of sources of visual discomfort and disability. The “quality of lighting” is a new concept not yet considered in professional lighting but already recognized in road lighting standards. The paper provides also suggestions for new measurement methodology and lighting fixture design are provided and, for dental practitioners, recommendations about position and eye protection system to wear to improve visual comfort and minimize MSD, due to misplaced working position to avoid glareembargoed_20200201Iacomussi, P.; Carcieri, P.; Rossi, G.; Migliario, M.Iacomussi, Paola; Carcieri, P.; Rossi, Giuseppe; Migliario, M

Epiregulin-loaded PLGA nanoparticles increase human keratinocytes proliferation: preliminary data

OBJECTIVE:Epiregulin is a member of the epidermal growth factor (EGF) family produced by keratinocytes: the aim of this study was to investigate the ability of biocompatible nanoparticles loaded with such growth factor to increase human keratinocytes proliferation. MATERIALS AND METHODS:Different PLGA (Poly-d,l-lactide-co-glycolide)-nanoparticles (NPs) formulations have been characterized in size and zeta potential by dynamic light scattering (DLS) analysis. The ability of the different PLGA-NPs formulations to adhere onto dental surfaces has been tested, and epiregulin-enriched PLGA-NPs has been produced. Epiregulin release from NPs has been tested by enzyme-linked immunosorbent (ELISA) assay and the proliferative effects of epiregulin-NPs on human keratinocytes have been evaluated. RESULTS:DLS analysis revealed a different size distribution depending on the PLA/PGA (poly lactic acid/poly glycolic acid) ratio used. 50:50 PLGA-NPs exhibited the smaller size and the best dental adhesive ability. Moreover, such epiregulin-loaded NPs was able to increase cell proliferation. CONCLUSIONS:Direct dental pocket drug delivery implies the NPs solution loading onto the dental surface at the cement-enamel junction level: 50:50 PLGA-NPs, with their small size and excellent adhesive ability, represent an interesting tool to deliver epiregulin directly where there is the need for epithelial proliferation. These results describe a possible strategy for periodontal pocket delivery of Epiregulin-loaded PLGA-NPs and might provide a new approach for the treatment of gingival recession, where gingival epithelium proliferation is needed

Pre-odontoblast proliferation induced by near-infrared laser stimulation

OBJECTIVE: Laser therapy is known to stimulate cell proliferation and differentiation, an effect called "biostimulation". Although many clinical applications of laser therapy take advantage from such positive effect, the underlying molecular mechanisms are not fully understood. The aim of this work was to investigate the effect of near-infrared laser stimulation on rat pre-odontoblast cells (MDPC-23 cells) and the molecular mechanism/s involved. MATERIALS AND METHODS: MDPC-23 cells were stimulated with a near-infrared (980 nm) laser source with different energy settings (1-50 J, corresponding to 0.65-32.47 J/cm2) and cell proliferation was evaluated by manual count. ERK 1/2 pathway activation was evaluated by Western blot analysis. RESULTS: 1-10 J stimulation (corresponding to 0.65-6.5 J/cm2) significantly increase MDPC-23 cell proliferation and such effect seems to be mediated by ERK 1/2 signalling pathway activation, showing a key role of ERK 1/2 pathway in mediating the proliferative response induced by laser stimulation. CONCLUSIONS: Near infrared laser stimulation with low energies (1-10 J) is able to increase cell proliferation through ERK 1/2 signalling pathway activation. At the same time, higher energy stimulation (25-50 J) induces an initial toxic effect, probably activating pro-apoptotic signalling molecules, downstream ERK 1/2 kinase. Such results foster the application of this therapeutic approach in different clinical settings in which a regenerative tissue response is needed

Correlation between Specific Bacterial Groups in the Oral Cavity and the Severity of Halitosis: Any Possible Beneficial Role for Selected Lactobacilli?

Objective: Halitosis is a widespread problem, normally attributable to specific volatile sulphur compounds (VSC) in the breath. The aim of this study was to first relate halitosis with possible gastric infection by Helicobacter pylori and secondly to quantify specific bacterial groups in the oral cavity flora, thus correlating them with VSC concentrations and Proton Pump Inhibitors (PPIs) intake. Four selected lactobacilli were then assessed in the possible reduction of halitosis in subjects with a total salivary bacterial concentration higher than 105 CFU/ml. Methods: Specific bacterial groups, namely total bacteria, total coliforms, sulphite-reducing bacteria (SRB) and lactobacilli, were quantified in samples of saliva from 29 subjects taking PPIs compared with 36 control subjects. The amount of the three VSC hydrogen sulfide (H2S), methyl mercaptan (CH3SH) and dimethyl sulfide (CH3)2S in the breath and the presence of H. pylori were determined. Results: No significant correlation was found between H. pylori and halitosis as well as with PPIs intake. The baseline bacterial groups quantification (log10 CFU/ml of saliva, PPI group vs. control) showed: total bacteria 8.44 vs. 4.47 (p=0.001); total coliforms 4.95 vs. 2.82 (p=0.001); sulfite-reducing bacteria 5.47 vs. 2.58 (p=0.052); total lactobacilli 4.00 vs. 2.36 (p=0.016). After 15 days of lactobacilli supplementation, the same parameters (d15 vs baseline) gave: total bacteria 7.92 vs. 8.44 (p=0.019); total coliforms 3.13 vs. 4.95 (p=0.001); sulfite-reducing bacteria 4.69 vs. 5.47 (p=0.047); total lactobacilli 7.86 vs. 4.00 (p=0.048). No statistically significant differences were noted in VSC concentrations at any time. Conclusions: The intake of PPIs directly correlated with the overgrowth of specific bacterial groups in the oral cavity, but there was no correlation with H. pylori or with VSC concentration. The significant reduction in all the bacterial groups analysed after two weeks suggested the improvement of the overall oral flora in subjects chronically treated with PPIs

Sarcopenic Dysphagia, Malnutrition, and Oral Frailty in Elderly: A Comprehensive Review.

Frailty is a highly prevalent condition in the elderly that has been increasingly considered as a crucial public health issue, due to the strict correlation with a higher risk of fragility fractures, hospitalization, and mortality. Among the age-related diseases, sarcopenia and dysphagia are two common pathological conditions in frail older people and could coexist leading to dehydration and malnutrition in these subjects. "Sarcopenic dysphagia" is a complex condition characterized by deglutition impairment due to the loss of mass and strength of swallowing muscles and might be also related to poor oral health status. Moreover, the aging process is strictly related to poor oral health status due to direct impairment of the immune system and wound healing and physical and cognitive impairment might indirectly influence older people's ability to carry out adequate oral hygiene. Therefore, poor oral health might affect nutrient intake, leading to malnutrition and, consequently, to frailty. In this scenario, sarcopenia, dysphagia, and oral health are closely linked sharing common pathophysiological pathways, disabling sequelae, and frailty. Thus, the aim of the present comprehensive review is to describe the correlation among sarcopenic dysphagia, malnutrition, and oral frailty, characterizing their phenotypically overlapping features, to propose a comprehensive and effective management of elderly frail subjects

The Oral Microbiome for Geographic Origin: An Italian Study

The human oral microbiome has primarily been studied in clinical settings and for medical purposes. More recently, oral microbial research has been incorporated into other areas of study. In forensics, research has aimed to exploit the variation in composition of the oral microbiome to answer forensic relevant topics, such as human identification and geographical provenience. Several studies have focused on the use of microbiome for continental, national, or ethnic origin evaluations. However, it is not clear how the microbiome varies between similar ethnic populations across different regions in a country. We report here a comparison of the oral microbiomes of individuals living in two regions of Italy – Lombardy and Piedmont. Oral samples were obtained by swabbing the donors’ oral mucosa, and the V4 region of the 16S rRNA gene was sequenced from the extracted microbial DNA. Additionally, we compared the oral and the skin microbiome from a subset of these individuals, to provide an understanding of which anatomical region may provide more robust results that can be useful for forensic human identification. Initial analysis of the oral microbiota revealed the presence of a core oral microbiome, consisting of nine taxa shared across all oral samples, as well as unique donor characterising taxa in 31 out of 50 samples. We also identified a trend between the abundance of Proteobacteria and Bacteroidota and the smoking habits, and of Spirochaetota and Synergistota and the age of the enrolled participants. Whilst no significant differences were observed in the oral microbial diversity of individuals from Lombardy or Piedmont, we identified two bacterial families – Corynebacteriaceae and Actinomycetaceae – that showed abundance trends between the two regions. Comparative analysis of the skin and oral microbiota showed significant differences in the alpha (p = 0.0011) and beta (Pr(>F) = 9.999e-05) diversities. Analysis of skin and oral samples from the same donor further revealed that the skin microbiome contained more unique donor characterising taxa than the oral one. Overall, this study demonstrates that whilst the oral microbiome of individuals from the same country and of similar ethnicity are largely similar, there may be donor characterising taxa that might be useful for identification purposes. Furthermore, the bacterial signatures associated with certain lifestyles could provide useful information for investigative purposes. Finally, additional studies are required, the skin microbiome may be a better discriminant for human identification than the oral one

“Touch microbiome” as a potential tool for forensic investigation: A pilot study

Human skin hosts a variety of microbes that can be transferred to surfaces (“touch microbiome”). These microorganisms can be considered as forensic markers similarly to “touch DNA”. With this pilot study, we wanted to evaluate the transferability and persistence of the “touch microbiome” on a surface after the deposition of a fingerprint and its exposure for 30 days at room temperature. Eleven volunteers were enrolled in the study. Skin microbiome samples were collected by swabbing the palm of their hands; additionally, donors were asked to touch a glass microscope slide to deposit their fingerprints, that were then swabbed. Both human and microbial DNA was isolated and quantified. Amelogenin locus and 16 human STRs were amplified, whereas the V4 region of 16 S rRNA gene was sequenced using Illumina MiSeq platform. STR profiles were successfully typed for 5 out of 22 “touch DNA” samples, while a microbiome profile was obtained for 20 out of 22 “touch microbiome” samples. Six skin core microbiome taxa were identified, as well as unique donor characterizing taxa. These unique taxa may have relevance for personal identification studies and may be useful to provide forensic intelligence information also when “touch DNA” fails. Additional future studies including greater datasets, additional time points and a greater number of surfaces may clarify the applicability of “touch microbiome” studies to real forensic contexts

Fattori di rischio, locali e sistemici: presente e futuro.

L’osteonecrosi dei mascellari su base ischemica o necrosi avascolare asettica può determinarsi per varie cause in ogni segmento scheletrico; non rappresenta una patologia autonoma quanto la conseguenza di fattori di rischio distinguibili in fattori locali e in fattori sistemici in grado di modificare il flusso ematico all’interno dell’osso e nei tessuti di rivestimento. Dalle prime segnalazioni di S. Ruggiero, R E. Marx e C.A. Migliorati in letteratura sono apparsi numerosi casi di pazienti in terapia con bifosfonati (BF) ed esposizione di osso necrotico a livello delle ossa mascellari. Oggi, sebbene non siano completamente chiariti i meccanismi d’azione, può ritenersi fondata l’associazione di lesioni osteonecrotiche dei mascellari con l’assunzione di bifosfonati. Dall’analisi della letteratura emerge che il rischio d’insorgenza della BRONJ è in relazione con il tipo di bifosfonato assunto (massimo per alte di BF contenenti gruppi amminici come il pamidronato, o nitrogeno come lo zoledronato), la dose, il tempo e la via di somministrazione, la patologia primaria per la quale il bifosfonato è somministrato, lo stato di salute generale del paziente e l’esposizione ossea a livello orale. Recenti studi pongono in rilevo anche lo stato infiammatorio cronico dei tessuti parodontali

Thirty-eight cases of bisphosphonate-related osteonecrosis of the jaws

For thirty-eight patients (16 males, mean age of onset lesions 69.31+SD 8.73, min 51.66\u201380.83; 22 females, mean age 67.76+9.53, min 43.25\u2013max 82.41) with bisphosphonate-related osteonecrosis of the jaw (BRONJ), gender, age, underlying diagnosis, type of bisphosphonate (BP), administration route and duration, location and stage of osteonecrosis, symptoms and oral health status, radiological findings, treatment and outcome, were recorded. Underlying diagnoses in the series were: 17 multiple myeloma, 7 breast cancer, 5 prostate carcinoma, 2 kidney cancer, 1 lung/bladder/mediastinal cancer, 1 chronic lymphocytic leukemia, 1 osteoporosis, 1 palatal osteosarcoma+osteoporosis, 1 non-Hodgkin\u2019s lymphoma. Fifty-seven osteonecrotic lesions were detected 36 localized in the mandible, 21 in the maxilla; trigger events was tooth extraction in 40 cases (70.2%), periodontal disease in 4 (7%), incongruous dentures in 3 (5.3%), perimplantitis in 1 (1.75%), unknown in 9 (15.75%). Thirty-six patients had received treatment using amino bisphosphonates (26 zoledronate, 6 pamidronate and zoledronate, 2 pamidronate, 2 alendronate),1 clodronate and 1 clodronate and ibandronate; the administration route was intravenous in 33 patients, oral in 2, intramuscular in 1 and intramuscular and oral in 1. Mean number of doses to bone exposure for patients was 22.44 + 14.70 for zoledronate, 48.33 + 14.47 for pamidronate and zoledronate, 32.50 + 44.55 for pamidronate, 146 + 161.22 for alendronate, 500 for clodronate and 77 for clodronate and ibandronate. Among statistical data the only significant finding was: the panoramic dental radiography gave no concrete support for diagnosis of ONJ lesions (p 64 0.04); the mean values of plaque index (PI 2.23 \ub1 SD 0.42) and gingival index (G.I. 2.38 \ub1 S.D. 0.36) had values higher than those (PI 1.56\ub1S.D. 0.94; GI 1.51\ub1S.D.0.78, p=0.037 and p=0.003) detected in a sample of subjects of the same age treated with bisphosphonate but without osteonecrotic lesions