Effect of Severe Dietary Magnesium Deficiency on Systemic Bone Density and Removal Torque of Osseointegrated Implants

Purpose This study evaluated the effect of severe magnesium (Mg) dietary deficiency on systemic bone density and biomechanical resistance of bone tissue to the removal torque of osseointegrated implants Materials and Methods The sample consisted of 45 rats, each received a titanium implant in their tibial metaphysis After 60 days, the animals were divided into three groups (n = 15) according to their dietary Mg the control group received the recommended content of Mg, group Mg1 received a 75% reduction in dietary Mg content, and group Mg2 was fed a diet with a 90% reduction in Mg con tent Animals were sacrificed 150 days after implant placement Serum concentrations of Mg were measured and the effect of Mg deficiency on systemic bone density was evaluated by densitometry of the lumbar vertebrae and femur Biomechanical characteristics were measured by resistance of the bone tissue to removal of the implants Results Lower Mg serum concentrations were found for the Mg1 and Mg2 groups, however, densitometric analysis and torque evaluations showed a statistically significant difference only in the Mg2 group (P < 05) There was a statistically significant difference in removal torque between the Mg2 group and the control group Conclusions This study showed that a severe deficiency of Mg decreased the systemic bone density and removal torque of osseointegrated implants INT J ORAL MAXILLOFAC IMPLANTS 2010 25 1125-1130

Analysis of workplace injuries in a dental school environment

Workplace injuries at the University of Queensland Dental School during the period 1992-1994 were assessed to determine their incidence, and the associated indirect costs, causal factors, and appropriate preventive strategies. Overall, dental chairside assistants experienced a higher incidence of injuries than students both on a per worker and per time basis. Of the injuries with a low risk of cross-infection, burns and scalds from sterilizing equipment, and eye injuries in laboratories were the most common. This emphasizes the importance of wearing appropriate protective equipment in areas outside the treatment zone, and the need for signage and education. Common causes of sharps injuries were burs left in handpieces, two-handed needle recapping, and cleaning of probes in the sterilizing room. Changes to techniques and equipment would prevent such incidents. A range of factors which contribute to the calculation of indirect costs following injuries in the dental workplace are identified.

Mandibular Function is Severely Impaired in Systemic Sclerosis Patients

Aims: To evaluate the presence of temporomandibular disorders (TMD) in systemic sclerosis (SSc) patients and its possible association with the severity of skin involvement. Methods: The presence of TMD was evaluated in 35 SSc women and 30 age- and sex-matched healthy controls by means of the anamnestic (A(i)) and clinical (D(i)) Helkimo indices; the jaw mobility was further analyzed (M(I)). Skin involvement was scored by the Modified Rodnan Skin Score (MRSS). Results: Signs and symptoms of TMD were more frequent in SSc patients than in controls, the frequency distribution of the different clinical dysfunction indices differing significantly (P < .001) between patients (D(i)0 8.6%, D(i)I 48.6%, D(i)II 22.8%, and D(i)III 20%) and controls (D(i)0 50%, D(i)I 33.3%, and D(i)II 16.7%). Cyclophosphamide for severe and rapidly progressive cutaneous fibrosis was prescribed in six out of seven patients with severe signs (D(i)III), in contrast this treatment was indicated for only two out of 25 patients with mild to moderate signs (D(i)I and D(i)II, P <. 001). Impaired jaw mobility was more frequent in SSc patients than controls (P < .001). It was severe in 77.1% (M(I)II) and mild in 22.9% (M(1)I) of the cases, in contrast to controls (M(I)0 33.4%, M(I)I 53.3%, and M(I)II 13.3%; P < .001). Approximately half of SSc patients with severe (M(I)II) but none of those with mild impairment were on cyclophosphamide treatment for severe cutaneous fibrosis (P = .02). Conclusion: Severe signs of TMD according to the anamnestic and clinical Helkimo indices were very frequent in SSc patients. J OROFAC PAIN 2010;24:197-202

The uncharged surface features surrounding the active site of Escherichia coli DsbA are conserved and are implicated in peptide binding

DsbA is a protein-folding catalyst from the periplasm of Escherichia coli that interacts with newly translocated polypeptide substrate and catalyzes the formation of disulfide bonds in these secreted proteins. The precise nature of the interaction between DsbA and unfolded substrate is not known. Here, we give a detailed analysis of the DsbA crystal structure, now refined to 1.7 Angstrom, and present a proposal for its interaction with peptide. The crystal structure of DsbA implies flexibility between the thioredoxin and helical domains that may be an important feature for the disulfide transfer reaction. A hinge point for domain motion is identified-the typo IV beta-turn Phe 63-Met 64-Gly 65-Gly 66, which connects the two domains. Three unique features on the active site surface of the DsbA molecule-a groove, hydrophobic pocket, and hydrophobic patch-form an extensive uncharged surface surrounding the active-sits disulfide. Residues that contribute to these surface features are shown to be generally conserved in eight DsbA homologues. Furthermore, the residues immediately surrounding the active-site disulfide are uncharged in all nine DsbA proteins. A model for DsbA-peptide interaction has been derived from the structure of a human thioredoxin:peptide complex. This shows that peptide could interact with DsbA in a manner similar to that with thioredoxin. The active-site disulfide and all three surrounding uncharged surface features of DsbA could, in principle, participate in the binding or stabilization of peptide.

Severe Periodontitis Is Associated With Diastolic Blood Pressure Elevation in Individuals With Heterozygous Familial Hypercholesterolemia: A Pilot Study

Background: This pilot study evaluates the association of severe periodontitis with pulse wave velocity (PWV), carotid artery intima-medial thickness (IMT), and clinical, metabolic, and atherogenic inflammatory markers in 79 subjects with heterozygous familial hypercholesterolemia (hFH). All subjects were free of previous vascular disease manifestations. Methods: The body mass index (in kilograms per square meter), plasma lipids, glucose, C-reactive protein, and white blood cell counts were evaluated. After full-mouth periodontal examinations, patients were categorized into the severe periodontitis group (SPG) or non-severe periodontitis group (NSPG). Results: The SPG showed significantly higher values of cholesterol-year scores, triglycerides, glucose, PWV, IMT, and diastolic blood pressure (DBP) (P <= 0.05) than the NSPG. After adjustment for traditional risk factors for atherosclerosis, only the association between severe periodontitis and DBP (odds ratio: 3.1; 95% CI: 1.1 to 8.5; P = 0.03) was confirmed. Conclusion: In individuals with hFH, severe periodontitis was associated with a higher DBP, which suggests that severe periodontitis, itself, may contribute to the increased cardiovascular risk profile in this population. J Periodontol 2011;82:683-688.

Orofacial granulomatosis: A diagnostic problem for the unwary and a management dilemma. Case reports

Orofacial granulomatosis is a condition that, may be difficult to diagnose for those unfamiliar with the entity. This paper describes two cases and addresses the presentation, pathogenesis and treatment. The clinical recognition of his condition is important as is the subsequent investigation by an appropriate specialist. Management of patients needs to take into account the results of further investigations, the patient's expectations, and the severity of the condition.

Body Posture Evaluations In Subjects with Internal Temporomandibular Joint Derangement

The aim of this study was to verify possible relationships between global body posture and temporomandibular joint internal derangement (TMJ-id), by comparing 30 subjects presenting typical TMJ-id signs to 20 healthy subjects. Body posture was assessed using the analysis of muscle chains on several photographs. Results show a higher frequency of lifted shoulders (p=0.04) and of changes in the antero-internal hip chain (p=0.02) in the test group, but no further differences were found significant between the control and test groups. The test group was then divided into three subgroups according to the Helkimo index of temporomandibular disorder severity. Again, no significant differences were found between the subgroups. However, there was a trend noticed in the group with the most severe dysfunction, to present a forward head and shoulders posture. Results are discussed in light of previous studies using the same sample.

Evaluation of oral-motor movements and speech in patients with tetanus of a public service in Brazil

The characterisation of oral-motor movements and speech of patients with tetanus were investigated to determine the existence of possible signs that are characteristic of this pathology. Thirteen patients clinically diagnosed with tetanus (10 with severe tetanus and three with very severe tetanus) and admitted to an intensive care unit underwent clinical evaluation of oral-motor movements and speech. Statistical analysis indicated significant between-group differences for speech motor functions, suggesting that individuals with very severe tetanus present rigidity as a characteristic interfering in articulatory precision (P = 0 035) and movement rate (P = 0 038). For lip closure, tongue movement, palatal elevation, gag reflex and voice quality, no between-group differences were identified for the specific abnormal characteristics. The observed abnormal results indicate that muscle strength and functional status of the oral-motor system presented by most of the participants of the study did not ensure the necessary integrity for satisfactory performance. The characterisation of the oral myofunctional aspects of patients with tetanus provides medical teams, patients and families with a wider and better description of the clinical situation, giving support to the diagnosis, prognostics and treatment.

Oral cavity is not a reservoir for Helicobacter pylori in infected patients with functional dyspepsia

Helicobacter pylori infection is very prevalent in Brazil, infecting almost 65% of the population. The aim of this study was to evaluate the presence of this bacterium in the oral cavity of patients with functional dyspepsia (epigastric pain syndrome), establish the main sites of infection in the mouth, and assess the frequency of cagA and vacA genotypes of oral H. pylori. All 43 outpatients with epigastric pain syndrome, who entered the study, were submitted to upper gastrointestinal endoscopy to rule out organic diseases. Helicobacter pylori infection in the stomach was confirmed by a rapid urease test and urea breath tests. Samples of saliva, the tongue dorsum and supragingival dental plaque were collected from the oral cavity of each subject and subgingival dental plaque samples were collected from the patients with periodontitis; H. pylori infection was verified by polymerase chain reaction using primers that amplify the DNA sequence of a species-specific antigen present in all H. pylori strains; primers that amplify a region of urease gene, and primers for cagA and vacA (m1, m2, s1a, s1b, s2) genotyping. Thirty patients harbored H. pylori in the stomach, but it was not possible to detect H. pylori in any oral samples using P1/P2 and Urease A/B. The genotype cagA was also negative in all samples and vacA genotype could not be characterized (s-m-). The oral cavity may not be a reservoir for H. pylori in patients with epigastric pain syndrome, the bacterium being detected exclusively in the stomach.