208 research outputs found
Standardised surface electromyography allows effective submental muscles assessment
The aims of this pilot study were to evaluate: (i) the reproducibility and variability of an electromyographical protocol developed for the assessment of submental muscles (SM) (ii) to apply the new protocol to maximal teeth clenching, a simple and largely studied static task in order to quantify the relative contribution of submental muscles. In 20 healthy subjects, aged 19-35years, surface electromyography of SM, masseter (MM) and anterior temporalis (TA) muscles was performed during maximal voluntary clenching (MVC) with and without cotton rolls and the pushing of the tongue against the palate. Clenching on cotton rolls and pushing the tongue against the palate were used to standardise respectively MM and TA, and SM muscular potentials. The exercises were repeated in two appointments (T1-T2); submental muscles standardisation was also repeated twice (A-B) in each session to assess repeatability. Symmetry and activity were calculated for each couple of muscles. A two-way analysis of variance was computed for SM: no Factor 1 (T1 vs T2) or Factor 2 (A vs B) or F1
7F2 significant effects were found. SM recruitment was 31% of the maximal activity, with symmetry values larger than 80%. In conclusion, standardised electromyography allows a reliable assessment of Submental muscles activity
Rapid Maxillary Expander and Eruption Guidance Appliance therapy in skeletal Class II: cephalometric considerations
AIM:
The use of rapid maxillary expander (RME) combined with eruption guidance appliances (EGA) represents a valid method in the treatment of skeletal Class II deep bite patients. In this paper a retrospective cephalometric study of the effects of RME and EGA therapy in Class II deep bite patients is described and compared with the treatment effects of patients with the same malocclusion treated only by RME.
MATERIALS AND METHODS:
Pre and post treatment cephalometric radiographs of 47 Class II division 1 deep bite growing patients treated with RME followed by EGA (mean age 9.65 years) (Group 1) were compared with those obtained from a control group (Group 2) of 44 patients (mean age 9.34 years) treated with RME only. The following cephalometric values were analized: SNA; SNB; ANB; SN-PNS.ANS; SN-Go.GN; N-Me; S-Go.
RESULTS:
Improvement in maxillo-mandibular relationship was observed in both groups with significantly higher decrease of SNA and ANB in group 1. The cranio-maxillary relation shows a tendency to grow downward and backward in both groups. Both anterior and posterior total facial heights showed a significant increase in group 1.
CONCLUSIONS:
RME followed by EGA therapy in Class II skeletal deep bite patients has shown better results compared with RME therapy without functional appliance
Effect of different dental articulating papers on SEMG activity during maximum clenching
This study evaluated the influence of two different occlusal indicators (articulating papers of 40\u3bcm and 200\u3bcm) on muscular activity of the temporalis anterior (TA) and superficial masseter (MS) during maximum voluntary clenches (MVC), using surface electromyography (SEMG). It was hypothesized that an articulating paper positioned between dental arches during MVC elicits a different muscular activity compared with the occlusion on natural dentition (without the occlusal indicator). 30 healthy adult subjects with a complete, natural dentition were recruited; SEMG activity was recorded in the following experimental conditions: MVC with cotton rolls for standardization purposes; MVC on natural dentition; MVC onto the 40 \u3bcm or 200\u3bcm paper indicator positioned on right or left side of the dental arch. Percentage Overlapping Coefficient (POC; separate values obtained for TA and MS), antero-posterior coefficient (APC) and total muscle activities (IMP) were the analyzed SEMG parameters. The use of an occlusal indicator statistically changed POC_TA, POC_MS and IMP median values (p 0.05). In conclusion, the examined articulating papers affected two specific SEMG parameters (POC and IMP); the recorded muscular activity with the occlusal indicator varied regardless left or right side positioning, and independently from tested paper thicknesses
Implant surfaces exposed to the oral cavity and treated with toothpaste containing oxygen releasing compound : a morphological controlled clinical trial
Aim of the present in vivo study is to assess if a toothpaste containing an oxygen releasing compound (AX) is able to
reduce the biofilm formation on implants with rough surface compared to a control toothpaste, without affecting the microstructure of the tested surface.
Methods: In this double blind, cross-over, controlled clinical trial, a total of fourteen healthy volunteers were recruited. For each
subject, two mandibular splints (test and control) were created with one implant fixed on the right lingual side of the mandibular
arch. The splint was continuously worn for 5 days and the daily hygiene was performed wearing the splint and using the test
(AX) or control toothpaste. Implants were analyzed at scanning-electron-microscopy and at laser profilometer for the assessment of biofilm adhesion (% of areas free from biofilm-FA) and surface changes (morphology and roughness).
Results: FA resulted significantly higher in test than in control implants. No differences were found between groups in term of
biofilm organization, surface microstructure and roughness.
Discussion: Daily use of toothpaste containing AX seems to reduce the amount of biofilm adherent to the rough implant surface
without corrosion or degradation of the titanium surface
Cephalometric traits in children and adolescents with and without atypical swallowing : a retrospective study
Aim It has been suggested that atypical swallowing (AS) may negatively influence the skeletal and alveolar development, but its specific effects are still unclear. The aim of this work is to compare the cephalometric characteristics of children and adolescents with and without AS. Materials and methods Study design: Case-control retrospective cross-sectional study. One hundred patients with (AS group) and 100 patients without AS (control group, C) were retrospectively selected. Their cephalometric data before orthodontic treatment were compared using a 3-way ANOVA variance test to detect any differences between groups considering: the type of swallowing (AS vs C); whether or not the second dentition was completed (SDC vs SDNC); and the gender (males-M and females-F). In addition, a Student-t test for unpaired data was carried out to detect differences between M and F within the AS and C groups. Results When compared to the controls, AS patients showed a significantly decreased SNB angle (p<.01), increased ANB and SN^Go. Me angles (p<.0001), increased overjet and lower facial height (p<.01), decreased overbite (p<.0001), and increased proclination of the upper incisors. AS-SDC patients also showed significantly increased alveolar length. Within the AS and C groups, skeletal and alveolar measurements were larger in males, with higher significance in the C group, suggesting a different trend of growth in AS patients. Conclusion AS seems to affect the skeletal growth causing mandibular clockwise rotation, skeletal Class II, open bite and incisor proclination. To compensate for these effects, an increase in alveolar growth together with molar eruption seems to be induced
Dental treatment of a rare case of pyoderma gangrenosum with aggressive periodontal disease
Background and Overview: Pyoderma gangrenosum (PG) is a rare neutrophil-mediated autoinflammatory dermatosis that can involve the oral mucosa. Dental surgery is a potential triggering factor for the onset of PG lesions. The authors describe and discuss the dental management of a rare case of aggressive periodontitis in a patient with PG, from multiple tooth extractions to prosthetic rehabilitation, including administration of systemic steroid prophylaxis before surgery to prevent the potential onset of PG-related lesions. Case Description: A 22-year-old man who had a diagnosis of PG and who had aggressive periodontal disease underwent dental extractions, gingivoplastic surgery, and prosthetic rehabilitation. The patient received 8 milligrams of betamethasone intramuscularly 20 minutes before the oral surgery. The tissues healed perfectly, and no adverse effects were reported. Conclusions and Practical Implications: For minor oral surgery, prophylactic corticosteroids might help reduce the risk of developing PG-related lesions. The clinician should plan the prosthetic devices to be as atraumatic as possible
Antimicrobial activity of zinc-doped hydroxyapatite coatings formed on titanium Ti6A14V surface for orthopedic implant
Prosthetic joint infection (PJI) is one of the most serious complications of prosthetic joint implantation leading to a longer hospitalization. S. aureus is the predominant cause of PJI followed by Pseudomonas aeruginosa and Stafilococci spp. coagulase negative. Several studies focused on the development of effective antibacterial surfaces that prevent bacterial adhesion, colonisation and proliferation into the surrounding tissues and it has been widely demonstrated that zinc ions (Zn2+) exhibit antimicrobial activity against various bacterial and fungal strains. In addition to its antimicrobial activities, zinc is important in healthy bone growth and development. The aim of this study was to evaluate the in vitro activity of Zn2+ generated from the partial dissolution of Zn particles on surface of titanium discs, against S. aureus ATCC 29213. Hydroxyapatite (HA), and HA/Zn2+ doped discs were used. Each disc was incubated with bacterial suspension following standard ASTM (American Society for Testing and Materials) method. After, colony-forming unit (CFU) were counted. The results showed 1,7 log10 (97,8 %) CFU decrease vs untreated samples (p< 0.05), after 6 hours of incubation. To confirm quantitative data, morphological analysis was performed by Scanning Electron Microscope (SEM). On HA disc, bacteria, recognized by the typical spherical shape, colonized micro and nano porosities surface assuming an homogeneous distribution, while on the surface doped with Zn2+, being smoother and less porous, the bacteria adhered to the surface in small colonies of about 2-10 bacteria. This new formulation of zinc coating could represent a promising approach for prevention and treatment of peri-implant diseases
Spermidine Associated to Non-Surgical Treatment of Periodontal Disease: Split Mouth Randomized Controlled Clinical Trial
Objectives. Spermidine is an endogenous polyamine whose increase induces the autocrine remodeling into targeted cells. The aim of the present study was to evaluate the adjunctive beneficial effects of the local delivery of spermidine to periodontal non-surgical therapy on reduction of periodontal pocket.
Methods. In this split mouth, blind, randomized controlled clinical trial, 20 patients with severe chronic generalized periodontal disease scheduled for cause related non-surgical periodontal treatment were enrolled. In three quadrants for each patients, three experimental teeth with probing pocket depth (PPD) 65 6mm were selected and randomly assigned to one of the following treatments: scaling and root planning (SRP)+ spermidine gel (spermidine + alginate) (group a), SRP+ placebo gel (only alginate) (positive control, group b) or SRP (negative control, group c). PPD at baseline, 3 and 6 months after treatment was assessed. Descriptive and inferential statistics was done.
Results. After periodontal treatment, a reduction of PPD was observed in all sites. No differences emerged between groups at each time point. In all groups, a significant PPD reduction was observed at T1 and T2 compared to baseline (p<0.05 and p<0.001). PPD reduction from T1 to T2 was significant only in group a (p<0.001).
Conclusions. After non-surgical treatment, local delivery of spermidine may induce prolonged improvement of clinical outcome
Palatal size and shape in 6-year olds affected by hypohidrotic ectodermal dysplasia
Objective: To analyze the size and shape of the hard tissue palate of Italian subjects with hypohidrotic ectodermal dysplasia (HED). Materials and Methods: The morphology and the dimensions of the hard tissue palate were analyzed in eight 6-year-old boys affected by HED. Four of the boys were completely edentulous and four partially dentate. Palatal landmarks were identified on stone casts and digitized with three-dimensional computerized electromagnetic instrumentation. Palatal length, slope, width, and maximum palatal height in both the sagittal and frontal planes were measured. From the coordinates of palatal landmarks, a mathematical equation of palatal shape was constructed, independent of size. HED palatal data were compared with reference data obtained from 12 healthy boys with a complete deciduous dentition. Results: Palatal length and height in both the sagittal and frontal planes were significantly reduced in HED as compared with control individuals. A less steep (not significant) palatal slope was found in HED than in reference subjects, whereas similar palatal width values were observed. All palatal measurements were larger in partially dentate than in edentulous patients. Both HED and edentulousness influenced palatal shape. The HED boys had a relatively lower palate than the reference boys. In the edentulous HED boys, the hard tissue palate was relatively lower than in partially dentate HED subjects. Conclusions: Palatal size and shape were significantly modified by the presence of hypohidrotic ectodermal dysplasia, and the major alterations were found in edentulous HED subjects
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