Effects of experimental occlusal interference on body posture: an optoelectronic stereophotogrammetric analysis.

In recent years, there has been increasing interest in the relationship between dental occlusion and body posture both among people and in scientific literature. The aim of the present longitudinal study is to investigate the effects of an experimental occlusal interference on body posture by means of a force platform and an optoelectronic stereophotogrammetric analysis. An occlusal interference of a 0- to 2-mm-thick glass composite was prepared to disturb the intercuspal position while not creating interference during lateral or protrusive mandibular excursions. Frontal and sagittal kinematic parameters, dynamic gait measurements and superficial electromyographic (SEMG) activity of head and neck muscles were performed on 12 healthy subjects. Measurements were taken 10 days before the application of the occlusal interference, and then immediately before the application, the day after it, and at a distance of 7 and 14 days under four different exteroceptive conditions. The outcomes of this study show that an occlusal interference does not modify significantly over time static and dynamic parameters of body posture under different exteroceptive conditions. It has a minimal influence only on the frontal kinematic parameters related to mandibular position, and it induces a transient increase of the activity of masticatory muscles. In this study, the experimental occlusal interference did not significantly influence the body posture during a 14-day follow-up period.

Self-assessed bruxism and phobic symptomatology.

AIM: The aim of this observational study was to compare two samples of patients (identified, from a previous survey carried out in 2007, as self-assessed bruxers and not) on the basis of the presence of anxious/phobic symptoms, general and linked to an oral surgery. METHODS: Forty-three bruxers and 207 non-bruxers were identified; among these last ones a sub-sample of 89 subjects was randomly selected as control and analyzed. The instruments for data collecting were two self-administered psychological questionnaires: STAI-Y1, Phobia Scale by Marks-Sheehan, and supplementary items on specific dental fear/phobia. RESULTS: No significant differences were observed for age, gender and occupation data but interestingly bruxers are significantly more represented among widows/divorced and graduated in comparisons with non-bruxers. Alcohol consumers were more frequent in bruxers than in non-bruxers (55.8% and 12.4%, respectively; P=0.0001). Global anxiety (P=0.02), agoraphobia, claustrophobia, pathophobia, social phobia (P<0.05), are more frequent in bruxers as also a suffocation feeling (P=0.02). The severity of behaviours that aim to avoid the same situations that causes phobias is low and similar in the two groups. CONCLUSION: The involuntary habit of clenching is, in our opinion, reported by the patients who control their anxiety/phobias without avoiding behaviours, increasing the muscular activity at a level relevant to bruxism.

Flow Cytometric Assessment of AKT Signaling in Platelet Activation: An Alternative Diagnostic Tool for Small Volumes of Blood.

INTRODUCTION: The diagnosis of platelet function disorder in children is challenging. Light transmission aggregometry is the gold standard for platelet function disorders. However, large blood volumes are required. Currently, there are no existing tools for the diagnosis of platelet function disorders that use small blood volumes. AKT signaling plays a central role in platelet activation during hemostasis and might be visualized by flow cytometry. METHODS: Platelet-rich plasma obtained by centrifugation of citrated blood from healthy volunteers was activated with arachidonic acid, thrombin receptor activating peptide-6 (TRAP-6), collagen, adenosine diphosphate ADP, collagen-related peptide (CRP), and epinephrine. After platelet activation, the phosphorylation of AKT was assessed by flow cytometer using a Navios cytometer. RESULTS: Healthy volunteers showed a reproducible phosphorylation of AKT upon activation. In comparison to nonactivated platelets, we documented an increase in pAKT expression with all agonists. Especially TRAP-6 and CRP caused considerable increase in percentage of pAKT expression throughout all the tested healthy volunteers. CONCLUSION: An activation of the AKT-signal pathway by different agonists can clearly be detected on the flow cytometer, indicating that the visualization of signaling in platelets by flow cytometry might be an efficient alternative for light transmission aggregometry to test platelet function in children.

Muscular pain caused by isometric contraction: evaluation of pain through visual analog scale.

Pain caused by muscular isometric contraction was investigated through use of the visual analog scale. The results demonstrate that the latency time and the time to reach maximum intensity are inversely proportional to the amount of the load; therefore increase of pain is linear. The high statistical significance of the results suggests that pain by isometric contraction could be a comparison test for somatic pain evaluation in spontaneous pathological conditions.

Effects of aerobic exercise on muscular pain sensitivity.

Muscular pain sensitivity after aerobic exercise was investigated in ten healthy men aged 20 to 30 years in four tests at five-day intervals to determine if previous aerobic work leads to a hyperalgesic status. The intensity of pain was recorded, by visual analog scale, every 30 seconds after the injection of 1 ml of 10% and of 20% sodium chloride hypertonic solution, both during basal conditions, and 1 ml of 10% sodium chloride hypertonic solution 1 and 60 minutes after 30 minutes of submaximal rectangular exercise. The injection of 10% sodium chloride solution 60 seconds after exercise gave rise to a clear increase in pain, similar to that induced by the 20% sodium chloride solution given during basal condition. This observation shows that submaximal exercise produces a hyperalgesic state in the active muscle. This hyperalgesia probably explains the clinical manifestation of latent algogenic triggers during physical activity.

Sucralfate: a help during oral management in patients with epidermolysis bullosa.

BACKGROUND: Epidermolysis bullosa (EB) is a group of genetic disorders that lead to blister formation at variable depths in skin and mucosa. Vesicles may arise spontaneously or be caused by friction or trauma. Oral tissue fragility and blistering is common in all EB types. The majority of patients with mild forms of EB are able to receive dental treatment. The prevention of dental caries is most challenging in subjects with severe mucosal involvement, as they are least able to routinely undergo correct preventive procedures. The aim of this study was to evaluate the effectiveness of a sucralfate suspension in reducing both pain and the number of blisters in patients with EB, and to obtain improved oral hygiene and a lower incidence of caries. METHODS: Five patients with dystrophic EB were treated with sucralfate suspension for the prevention and management of oral blisters. Oral blisters were assessed using a quantitative scale, while pain was assessed using visual analogue scale (VAS), and hygiene was evaluated through plaque and gingival indexes. RESULTS: The number of blisters, oral pain, and plaque decreased in all cases. CONCLUSIONS: Oral prophylaxis with sucralfate prevented oral blisters and oral discomfort. The procedure proved to be cost effective and easy to administer. It did not show significant side effects and may be used routinely in patients with EB.

Intraoral fluoride releasing device: a new clinical therapy for dentine sensitivity.

BACKGROUND: Dentinal sensitivity (DS) occurs frequently in adult populations in western countries. The purpose of this work was to assess the effectiveness of a new intraoral fluoride releasing device (IFRD) in reducing the level of pain in patients with primary or postsurgical dentine sensitivity. METHODS: A total of 49 individuals were selected for this study, 15 of whom had post-periodontal surgery dentine sensitivity and 34 with primary sensitivity. An IFRD was applied to 39, while 10 received a placebo device. All individuals in the control group suffered from primary sensitivity. The IFRD used in this study consists of sodium fluoride encased in an acrylic polymer which releases fluoride at a rate of approximately 0.04 mg/day. All patients were asked to rinse with cold water (10 degrees C) and to indicate the level of pain on a 0 to 10 visual analog scale, 0 equalling "no pain" and 10 "maximum bearable pain." All subjects were evaluated once a week during 4 months. Statistical analysis of dentine sensitivity was performed as a univariate study, in relation to the main factors: age, gender, and primary sensitivity or postsurgical etiology. RESULTS: Symptoms decreased dramatically in all treated patients. The level of sensitivity did not change during the first week after IFRD application, but decreased significantly within the fourth week and remained absent through the duration of the treatment (P <0.01). Difference in sensitivity with respect to different etiology was significant only after 4 weeks (P= 0.01), while there was no statistical difference with respect to age or gender. CONCLUSIONS: This paper is an initial study to evaluate the effectiveness of the IFRD. The method is fast, painless, inexpensive, and it appears to be suitable as a routine treatment. The presented data support the conclusions at this stage and warrant more comprehensive evaluation.

Simulated disability exercises and their impact on attitudes toward persons with disabilities.

Two separate graduate rehabilitation counselling groups from a mid-south university either did or did not take part in a wheelchair sensitivity training pilot study designed to enhance their understanding as to what life might be like for persons who use a wheelchair. Twenty students were individually accompanied on a designated route across campus by a non-disabled graduate researcher. Eighteen other graduate students formed a control group and did not participate. Both groups completed a contextually different 14-item Likert type questionnaire designed to assess their perceptions of persons with physical disabilities based on either the sensitivity exercise or their experience in the rehabilitation programme. Results from this quasi-experimental study suggested that regardless of whether they participated in the sensitivity training, both groups perceived they would become better counsellors. t-Tests revealed significant differences in the two groups' responses to questions pertaining to daily frustrations experienced by persons with physical disabilities and a pre-occupation with how accessible places are. Other differences noted were that persons with physical disabilities must feel different from being stared at and must have a harder time in society. Implications of the utility and misuses of these one-time experiences are explored.

Headache and cranio-mandibular disorders during adolescence.

A clinical and epidemiological investigation was performed on 62 adolescents, 21 males and 41 females, with recurring headaches, in order to analyze the connections between the cephalalgia and the signs and symptoms of mandibular dysfunction. The anamnestic and objective data were reviewed with the aid of the Helkimo indices and compared to data on a control group of comparable age who were not headache sufferers. The most statistically significant signs encountered (p < 0.001) were: pain on palpation of masticatory muscles (61%), altered (43%) or reduced (27%) mandibular movement, preauricular tenderness (19%); the high incidence of parafunctions indicated the behavioral substrate. This pilot study reveals a link between the two pathologies and the need for early diagnosis, preventive identification of the subjects at risk and interdisciplinary cooperation.

Alpha-crystallin: an ATP-independent complete molecular chaperone toward sorbitol dehydrogenase.

alpha-Crystallin, the major component of the vertebrate lens, is known to interact with proteins undergoing denaturation and to protect them from aggregation phenomena. Bovine lens sorbitol dehydrogenase (SDH) was previously shown to be completely protected by alpha-crystallin from thermally induced aggregation and inactivation. Here we report that alpha-crystallin, in the presence of the SDH pyridine cofactor NAD(H), can exert a remarkable chaperone action by favoring the recovery of the enzyme activity from chemically denaturated SDH up to 77%. Indeed, even in the absence of the cofactor, alpha-crystallin present at a ratio with SDH of 20:1 (w:w) allows a recovery of 35% of the enzyme activity. The effect of ATP in enhancing alpha-crystallin-promoted SDH renaturation appears to be both nonspecific and to not involve hydrolysis phenomena, thus confirming that the chaperone action of alpha-crystallin is not dependent on ATP as energy donor.

Chaperone-like features of bovine serum albumin: a comparison with alpha-crystallin.

The chaperone behaviour of bovine serum albumin was compared with that of alpha-crystallin. The chaperone activity was assessed by measuring: (i) the ability to antagonize protein aggregation induced by heat; (ii) the capability to protect the activity of thermally stressed enzymes and (iii) the effectiveness in assisting the functional recovery of chemically denatured sorbitol dehydrogenase. Despite the lack of structural analogies, both proteins show several functional similarities in preventing inactivation of thermally stressed enzymes and in reactivating chemically denatured sorbitol dehydrogenase. As with alpha-crystallin, the chaperone action of bovine serum albumin appears to be ATP independent. Bovine serum albumin appears significantly less effective than alpha-crystallin only in preventing thermally induced protein aggregation. A possible relationship between chaperone function and structural organization is proposed. Together, our results indicate that bovine serum albumin acts as a molecular chaperone and that, for its particular distribution, can be included in the extracellular chaperone family.

Stomatognathic function in juvenile rheumatoid arthritis and in developmental open-bite subjects.

Patients affected with juvenile rheumatoid arthritis present clear radiological alterations of the condyles of the temporomandibular joint (TMJ) due to the inflammatory process, with a prevalence ranging from 17 percent to 63 percent. This work is a comparison between a group of subjects with juvenile rheumatoid arthritis presenting signs and symptoms of TMT dysfunction and a group of the same age not suffering from any rheumatic morbidity, but presenting an open bite > 3 mm. The aim is to verify whether the open bite can induce an alteration in mandibular function comparable to that observed in juvenile rheumatoid arthritis. Statistically significant difference is found in the juvenile rheumatoid arthritis group only regarding spontaneous and provoked muscle pain and the lateral opening deviations of the mouth, but mostly the two groups seem alike and present the same stomatognathic pattern.

Complete protection by alpha-crystallin of lens sorbitol dehydrogenase undergoing thermal stress.

Sorbitol dehydrogenase (l-iditol:NAD(+) 2-oxidoreductase, E.C. 1.1.1. 14) (SDH) was significantly protected from thermally induced inactivation and aggregation by bovine lens alpha-crystallin. An alpha-crystallin/SDH ratio as low as 1:2 in weight was sufficient to preserve the transparency of the enzyme solution kept for at least 2 h at 55 degrees C. Moreover, an alpha-crystallin/SDH ratio of 5:1 (w/w) was sufficient to preserve the enzyme activity fully at 55 degrees C for at least 40 min. The protection by alpha-crystallin of SDH activity was essentially unaffected by high ionic strength (i.e. 0.5 m NaCl). On the other hand, the transparency of the protein solution was lost at a high salt concentration because of the precipitation of the alpha-crystallin/SDH adduct. Magnesium and calcium ions present at millimolar concentrations antagonized the protective action exerted by alpha-crystallin against the thermally induced inactivation and aggregation of SDH. The lack of protection of alpha-crystallin against the inactivation of SDH induced at 55 degrees C by thiol blocking agents or EDTA together with the additive effect of NADH in stabilizing the enzyme in the presence of alpha-crystallin suggest that functional groups involved in catalysis are freely accessible in SDH while interacting with alpha-crystallin. Two different adducts between alpha-crystallin and SDH were isolated by gel filtration chromatography. One adduct was characterized by a high M(r) of approximately 800,000 and carried exclusively inactive SDH. A second adduct, carrying active SDH, had a size consistent with an interaction of the enzyme with monomers or low M(r) aggregates of alpha-crystallin. Even though it had a reduced efficiency with respect to alpha-crystallin, bovine serum albumin was shown to mimic the chaperone-like activity of alpha-crystallin in protecting SDH from thermal denaturation. These findings suggest that the multimeric structural organization of alpha-crystallin may not be a necessary requirement for the stabilization of the enzyme activity.

A retentive system for intra-oral fluoride release during orthodontic treatment.

The aim of this study was to test a particular type of intra-oral fluoride releasing device (IFRD), designed to release 0.04 mg/day of fluoride over a period of 6 months, using customized holders, in patients receiving orthodontic treatment. Discomfort, holder detachment, plaque accumulation near the device, and the presence of gingivitis, bleeding, white spot lesions, and/or decay was recorded in 76 orthodontic patients (53 experimental and 23 controls) before and after wearing the device for 12 months. The system proved to be easy and quick to use, and did not cause discomfort. There were no significant differences between the treated and the control groups for plaque index, bleeding, or the presence of gingivitis. In addition, no carious and/or white spot lesions occurred during the duration of this study in the test group.

[Behavior of cardiorespiratory parameters in ischemia induced in the lower limbs. I) Monolateral ischemia]. / Comportamento di alcuni parametri cardiorespiratori in ischemia provocata degli arti inferiori. I) Ischemia monolaterale.

The subject of present research has been to study the effects of ischemia determining pain and cardiorespiratory modifications observed during and after isometric contraction of a quadriceps muscle subjected to a constant load. Therefore, in the same lower limb used for the previous test; an ischemia has been caused and protracted for the same amount of time. During and after the test the pain's intensity, VE, HR and VO2 have been noted. The obtained results have been subjected to statistic survey which has not proved significant variations of the studied cardiorespiratory parameters. Moreover pain has not arise during the test. A supposition that in those conditions only a little quantity of active metabolites can, be made. They conclude, therefore, that ischemia is a modest component in the cardiorespiratory modifications' determinism obtained with a test of isometric contraction of a quadriceps muscle subjected to a constant load.