Influence of posture on swallowing.

AIM: This study investigates the relationship between posture disorders and swallowing, either of infantile type or affected by the presence of a short lingual frenulum. MATERIALS AND METHODS: The stabilometry examinations, taking into account the Romberg index and the LFS value, and when needed a frenectomy, showed positive variations in the recovery of a proper posture. The data were analysed by means of the Wilcoxon signed-rank test. RESULTS AND CONCLUSION: This study showed that swallowing is able to modulate postural control and it can be a determining factor in postural syndromes that, if not promptly intercepted, may evolve into full-blown and irreversible musculoskeletal disorders for which treatment often proves ineffective.

Low cadmium concentration in whole blood from residents of northern Sardinia (Italy) with special reference to smoking habits.

INTRODUCTION: The present study was initiated to investigate the cadmium concentrations in whole blood of Northern Sardinian, non-occupationally exposed adult subjects. Sardinia is a large Italian island which differs genetically and environmentally from other mainland Italian areas. METHODS: Two hundred and forty-three adults (157 females and 86 males) were selected in the study area from subjects who were undergoing blood collection for laboratory analysis during the period January 2005-May 2005. Whole blood was analysed by graphite furnace atomic absorption spectrometer equipped with a Zeeman-effect background corrector (Perkin Elmer ZLS5100) and an auto sampler. The adopted analytical procedure uses the Stabilized Platform Temperature Furnace (STPF) technique. RESULTS: The mean value of Blood Cadmium Concentration (BCdC), expressed as Geometric Mean, was 0.32 pg/l (CI 95%: 0.31-0.34 l) in non-smokers to 034 pg/l (CI 95%: 0.30-0.39 pg/l) in ex-smokers up to 0.47 gg/ll(CI 95%: 0.42-0.53 pg/l) in smokers (p < 0.0001). DISCUSSION: The results show that BCdC levels in Northern Sardinian non-occupationally exposed adults are lower than levels found in many other regions, including those within Italy. Nevertheless, similar values have been detected in other European countries and cities. CONCLUSIONS: In relation to other reports in which data were analysed by strata for smoking habit and age, we found similar BCdC values among non smokers. However, Sardinian smokers seem to show lower levels of blood cadmium.

Ages of eruption: study on a sample of 204 Italian children aged 6 to 24 months.

AIM: The purpose of this study is the evaluation of the tooth eruption ages in a sample of children aged between 6 and 24 months. MATERIALS AND METHODS: The sample consists of 204 children aged between six and twenty-four months, followed up for a period of one year in collaboration with seven pediatricians in the province of Sassari (Italy). The visits were carried out at the paediatricians' practice in order to receive immediate feedback about the clinical conditions of children. RESULTS: Regarding the ages of eruption of all elements it was observed a shift more or less important, depending on the tooth considered.

Carboplatin sustained delivery system using injectable microspheres.

A controlled carboplatin delivery system using biodegradable polymer has been used in this study. The purpose was to evaluate the local and systemic effects of injectable, biodegradable microspheres containing carboplatin when injected as aqueous suspension subcutaneously in rats. Biocompatibility and toxicity of empty microspheres and microspheres loaded with carboplatin were evaluated by clinical and histological examination. The diffusion of carboplatin in tissues and time of drug release were evaluated by platinum determination in plasma and tissues over the time. The results of the study suggest that microspheres provide a sustained slow release of carboplatin and that multiple inoculations of microspheres containing drug and no evidence of local or systemic toxicity is found. This device may be useful in the treatment of solid tumours.

[The influence of occlusion on sporting performance]. / Influenza dell'occlusione sulle prestazioni sportive.

AIM: The purpose of the present study is to investigate the relationship between dental occlusion and physical performance using the Ergo-jump platform, and to highlight connections, if any. METHODS: For the purpose of this research, 30 patients suffering from cervico-facial pathology and 10 without temporomandibular joint dysfunction were selected from within the Dental Clinic of the University of Sassari. For the first group a resin plate was prepared to correct the malocclusion, while for the control group a bite was prepared that created it. Subjects carried out exercises with the Ergo-jump platform, a device that assesses physical capabilities and athletic performance. Patients were asked to do 2 exercises, a counter movement jump and a mechanical power test, with plate and without plate. RESULTS: The tests of the first group were as follows: flying times with the bite were 0.01 s longer; the average elevation in the counter movement jump test did not give statistically significant results; execution of the mechanical power test suggests an increase in average mechanical power with the plate. Execution of the same exercises in the other group showed greater flight times without the place; average elevation was not statistically significant; the execution of the mechanical power test showed a decrease in average mechanical power with the occlusion plate. CONCLUSION: Statistical analysis of individual results showed that patients do not always obtain a benefit during physical exercise using the bite. Research shows that the same pathology can cause different physical performance in different individuals; in fact, not all craniomandibular disturbances have repercussions on posture.

[Morphologic evaluation of adhesive/resin cement system and fiber post: a sem investigation]. / Valutazione morfologica al Sem della cementazione adesiva dei perni in fibra di quarzo.

AIM: The purpose of the present paper is to carry out an SEM investigation into the adhesive cementation of quartz fibre posts in canals treated with endodontic cements containing or not containing eugenol. METHODS: Sixteen selected tooth roots were subdivided into 4 groups and prepared with the step-back technique. Group A, without canal filling and with a cemented post, was the control group; in groups B and C, the canals were closed with guttapercha, endomethasone C and eugenol, those of group D with guttapercha and AH Plus without eugenol. The canals were prepared so as to be able to take D.T. light-posts irrigated with water (group C with ethyl alcohol) mordanted with orthophosphoric acid after applying 2 layers of photopolymerised ONE-STEP; 2 layers of ONE-STEP were applied to the post. DUO-LINK cement was positioned in the canal after inserting the post, removing excess resin and photopolymerising. The samples were prepared for SEM observation. RESULTS: Group A: the apical portion shows the post absorbed into the cement and resin tags; group B: porosity is noted between cement and post, the hybrid layer does not present tissue penetration of the dentin resin; group C: bullae can be seen between cement and post surface and between hybrid layer and cement; group D: there is relative continuity between post surface, cementing resin, hybrid layer and underlying dentin. CONCLUSION: The study has shown that eugenol interferes with the formation of the hybrid layer, the pictures relative to the resinous cement appeared different depending on whether the canal was treated with cement containing or not containing eugenol.

[Stabilimetry and cranio-cervico-mandibular disorders]. / Stabilometria e disturbi cranio-cervicali mandibolari.

BACKGROUND: Cranio-cervico-mandibular disorders can cause disturbances in posture. Stabilimetry measures spatio-temporal variations in the center of body pressure and evaluates the mechanisms of maintenance of balance. The study used a stabilimetric platform to evaluate posture changes in patients with cranio-cervico-mandibular disorders before and after treatment for malocclusion. METHODS: Between February 1998 and December 2000, 60 patients with cranio-cervico-mandibular disorders were recruited from the Dentistry Clinic of the University of Sassari. Each patient underwent two stabilimetric examinations (closed mouth with cotton wads inserted between the dental arches). The tests were conducted on a stabilimetric platform. Measurement of body posture load and sway were analyzed with a specific software program that correlated the vestibular, somatosensory and visual systems, and determined the role of each in postural control. RESULTS: The stabilimetric analysis showed that the adoption of the plaque allowed rebalance of the postural system, without affecting the visual system. After treatment, 64% of patients experienced remission of pain symptoms with orthotic therapy. CONCLUSIONS: The relationship between malocclusion and posture should be seen from a holistic standpoint in other to gain a global therapeutic outcome.

[In vivo evaluation of carbon fiber posts]. / Valutazione dell'affidabilità clinica dei perni di terza generazione.

BACKGROUND: The use of carbon fiber posts allows morpho-functional restoration of endodontically treated teeth with an assembly of materials of a modulus of elasticity similar to that of dentin. The study clinically evaluated the percentage of survival of dental elements treated and reconstructed with endocanal carbon fiber posts. METHODS: At the Dentistry Clinic of the University of Sassari 60 dental elements were selected from 46 subjects. The teeth, which had been treated endodontically with success for at least six months, were classified by parameters taken from the international literature and reconstructed using Tech 2000 carbon fiber posts and adhesive resinous systems recommended by the post manufacturer. RESULTS: The success rate was 98.4%. Almost half (49%) of the samples were single-rooted elements, 37.4% of the posts were 1.2 mm in diameter; in 78.3% the opposing contact was with a natural tooth; 100% of the elements had a type A dental structure. CONCLUSIONS: Third generation posts are a valid alternative to metallic posts and improve the prognosis of the treated element. The carbon fiber posts fixed with the composite, forming a single unit with the dental element, thus improving mid-term RESULTS. The technique is easy to use under clinical conditions and can be performed in a single session. So far, the method has provided promising clinical results, as this study demonstrated.

[Calcium heparin-induced immunologic thrombocytopenia complicated with venous gangrene of the legs. Report of a clinical case]. / Trombocitopenia immunomediata da eparina calcica complicata da gangrena venosa a carico degli arti inferiori. Descrizione di un caso clinico.

An 80-year-old woman was admitted to the Traumatologic Hospital of Florence because of bilateral post-traumatic humeral fractures. Subcutaneous calcium heparin was immediately administered to prevent deep venous thrombosis. Nine days later, the patient was referred to the Internal Medicine Unit because of severe immune-mediated heparin-induced thrombocytopenia and bilateral deep venous thrombosis. Heparin therapy was immediately discontinued, and the patient was switched to warfarin therapy. Diagnosis of heparin-induced thrombocytopenia was confirmed by positivity of anti-heparin-PF4 antibodies. On the second day of warfarin therapy, bilateral limb venous gangrene with a high risk of limb amputation appeared. To reduce thrombin generation, i.e., the mechanism by which heparin-induced thrombocytopenia induces thrombotic events, intravenous treatment with dermatan sulphate and low-dose urokinase was initiated. After 10 days of treatment, the limb venous gangrene disappeared, and low-dose warfarin therapy was again introduced. The patient was discharged 40 days after admission, and a Doppler ultrasound study showed only minimal signs of deep vein thrombosis in the right popliteal veins. Although in Italy the use of dermatan sulphate has been limited to the prevention of deep vein thrombosis, this case shows that it should be considered a useful agent for the treatment of thrombotic complications secondary to heparin-induced thrombocytopenia. Patients with acute immune-mediated heparin-induced thrombocytopenia should not be treated with warfarin alone. Frequent platelet count monitoring from day 5 of heparin treatment remains the best means of early detection of immune-mediated heparin-induced thrombocytopenia.

[Baropodometric examination for complete diagnosis of patients with cranio-cervico-mandibular disorders]. / L'esame baropodometrico nella diagnosi global dei pazienti con disordini cranio-cervico-mandibolari.

BACKGROUND: The aim of this study was to evaluate the relationship between craniomandibular disorders and postural alterations using baropodometric examination. METHODS: All tests were carried out in the Department of Dentistry at Sassari University in a population of patients with cranio-cervico-mandibular disorders (CCMD) of various types and severity. A total of 10 subjects (mean age approximately 30 years) with this pathology were evaluated over 7 months. All patients were treated using the following protocol: objective functional and clinical examination, radiographic tests, occlusal treatment using acrylic resin plate, baropodometric test with static and dynamic posture assessment, with eyes open and closed, before and after treatment with orthesis. RESULTS: An improved postural position was observed in 80% of cases, of which 30% showed an improvement in both static and dynamic posture, 20% only in static and 30% only in dynamic; these results highlighted the importance of baropodometric analysis in the correct treatment of patients with CCMD and postural disorders. CONCLUSIONS: This study confirms the need for a holistic approach to odontostomatological disciplines and the importance of a modern preventive and/or therapeutic approach to orthodontic problems and CCMD, especially when fixed or removable biomechanical devices are used.

Sequence, cloning, expression and characterisation of the 81-kDa surface membrane protein (P80) of Mycoplasma agalactiae.

Mycoplasma agalactiae, the causative agent of contagious agalactia in small ruminants, produces a protein, named P80, that is detectable in all wild-type isolates examined to date and that appears expressed during the early phase of infection. We describe here the identification, cloning and expression of the gene encoding P80 (ma-mp81). The deduced amino acid sequence is consistent with a hydrophobic and basic protein that possesses a lipoprotein signal peptide. Sequence analysis of gene ma-mp81 suggests that P80 is a membrane lipoprotein that shows significant homology with other putative lipoproteins of M. pneumoniae. An internal 1-kb fragment of ma-mp81 was expressed in Escherichia coli as a 6xHis-tagged protein. The purified recombinant protein greatly reacted with polyclonal anti-P80 sera raised in lamb.

Jaw muscle response to stimulation of type II somatosensory afferents of limbs in the rat.

Convergence of various afferent inputs onto brainstem neurones may play an important role in the regulation of trigeminal motor activity. In particular, previous studies suggest that, besides sensory inputs arising from the orofacial region, extratrigeminal information may modulate jaw muscle function. In the present study the actions exerted on masseter and digastric muscles by the activation of somatosensory afferents coming from fore- and hind limbs were examined. The electromyographic activity (EMG) of masseter and digastric muscles was recorded in 20 anaesthetised rats, and EMG responses to single and paired electrical stimulation of common radial and sciatic nerves, at a threshold intensity for the activation of group II afferent fibres, were studied. The stimulation induced an excitatory response in both masseter and digastric muscles bilaterally. Ipsiand contralateral radial nerve stimulation evoked masseter responses at latencies of 13.8 +/- 2.4 ms and of 18.0 +/- 2.6 ms, respectively, and digastric responses 1.6 +/- 0.4 ms later. Ipsi- and contralateral sciatic nerve stimulation elicited masseter responses at latencies of 21.4 +/- 2.6 ms and of 23.3 +/- 2.0 ms, respectively, and digastric responses 2.0 +/- 0.2 ms later. The same masseter and digastric motor units were excited by both radial and sciatic nerve stimulation; this suggests a convergence of somatosensory inputs arising from fore- and hind limbs on the same pool of masseter and digastric motoneurones. Paired stimulation of the two nerves did not induce any summation of the responses; this finding suggests that the two inputs, reaching a common relay station, could give rise either to occlusion or to inhibitory interactions. Spinotrigeminal relationship evidenced in this study may be involved in the coordination of jaw and limb movements.

[Mercury determination in human amniotic fluid]. / Dosaggio del mercurio nel liquido amniotico umano.

BACKGROUND: One of the components of Ag amalgam is mercury which, owing to its organic derivatives, can pass into the organs and biological fluids. One particularly interesting but worrying aspect of this transition is the possibility that mercury may pass through the placental barrier and reach the fetus. The aim of this study was to evaluate the concentration of total mercury in human amniotic fluid and compare it with the number and occlusal extension of fillings using Ag amalgam. METHODS: A group of 56 pregnant women were selected due to undergo amniocentesis. A dental check-up was carried out in each patient to identify the number and extension of amalgam fillings. Mercury levels in the amniotic liquid were assayed using a spectrophotometer with atomic absorption and a FIAS-amalgam technique. RESULTS: Mercury concentrations in the samples examined ranged from a minimum of 0.00 ng/ml to a maximum of 2.55 ng/ml, mean 0.44 +/- 0.53 ng/ml. The correlations between the variables examined were evaluated by calculating the coefficient of linear regression. No direct relationship was found with mercury levels. The data obtained were used to construct a model of logistic regression showing scant statistical significance (p = 0.05) between the number of fillings and mercury levels, whereas the occlusal extension of dental repairs was significantly correlated with metal concentrations (p < 0.05). CONCLUSIONS: The authors recommend that silver amalgam should be used with considerable caution during pregnancy.

Masseter muscle activity during vestibular stimulation in man.

Experimental data report that vestibular afferents affect trigeminal system activity. The aim of this work was to evaluate whether static vestibular stimulation affects the excitability of trigeminal motoneurons in man. In order to assess this, voluntary EMG activity of masseter muscles as well as duration and latency of the early and late components of EMG exteroceptive silent period were evaluated while keeping the subject in vertical position and during 20 degrees static tilt. The experiments were performed on ten adult subjects with no orofacial, neurologic and otologic disorders. Each subject sat on a chair, which kept the complex head-jaw-neck-trunk and the limbs securely fixed, in order to minimize any interference due to the activation of somatosensory and proprioceptive afferents from these districts. The subjects were instructed to contract masseter muscles at 25% of their maximum bite force and the isometric force monitoring was used as visual feedback. Exteroceptive silent period (ESP) of masseter EMG was elicited by electrically stimulating the inferior inter-incisal gum. Results showed that static vestibular stimulation induced asymmetrical responses on voluntary masseter muscle activity, which was reduced to 70.3 +/- 16.1% (mean +/- S.D.) of the control value during ipsilateral tilt and increased to 128.8 +/- 13.0% during contralateral tilt. The duration of the early (ESP1) and late (ESP2) silent periods was also affected: during ipsilateral tilt ESP1 and ESP2 duration increased to 130.0 +/- 3.5% and to 122.1 +/- 2.1% of control, respectively; during contralateral tilt it was reduced to 76.8 +/- 1.2% and to 83.0 +/- 1.7% of control, respectively. On the contrary, changes in latencies were not significant. These data evidenced an asymmetrical effect exerted on trigeminal motor activity by static tilt. Since the influence of all receptors which could be activated by static tilt, except that arising from the macular ones, was minimized in this study, it is likely that the observed effects, induced by static tilt on masseter muscle activity, were of macular origin.

[In vitro evaluation of mercury leakage from dental amalgam using atomic absorption spectrophotometry]. / Valutazione in vitro del rilascio di mercurio dall'amalgama dentale mediante spettrofotometro ad assorbimento atomico.

OBJECTIVE: The use of silver amalgam as a tooth filler is under constant critical review because of its mercury content. After a review of the literature on this subject, in vitro spectrophotometry was used to assay the release of mercury by these amalgams in basal conditions. METHODS: The experiment was conducted in two phases using standard doses of amalgam. In Phase 1 Black Class I cavities were created in extracted teeth that were big enough to take the required dose of amalgam. In some cases the material was inserted in a single operation, while in others the amalgam was introduced in three stages. Some of the cavities were cleansed with cotton buds bathed in ethyl alcohol, while others were not. All the drilled teeth were imbued in a bath of artificial saliva held at a constant temperature. In the second experiment, crushed amalgam was immersed in a similar bath of artificial saliva but otherwise untreated. The saliva was assayed after different time lapses using atomic absorption spectrophotometry and the FIAS technique. RESULTS: The results showed extremely variable but always modest quantities of free mercury in the artificial saliva. CONCLUSIONS: The findings suggest that not all the mercury available in the amalgamation phase is involved in the formation of the crystalline reticulum and that the percentage of mercury bonded is different every time. While the titre of free mercury encountered was always extremely low and hard to predict, it cannot be ignored.

Trigeminal integration of vestibular and forelimb nerve inputs.

Experiments were carried out on anaesthetized guinea pigs to evaluate whether vestibular and somatosensory informations converge upon the same trigeminal motoneurones and, if so, how they interact in the modulation of their activity. It was found that excitatory responses occurred in these motoneurones when an appropriate electrical stimulation was applied to the common radial nerve. The same was true if the electrical stimulus was applied to the vestibular ampullae. In another set of experiments the stimulation was applied both to the vestibular ampullae and to the common radial nerve at various time-intervals. The amplitude of the motoneuronal responses to common radial nerve stimulation was reduced when preceded by a vestibular stimulation. The same was true when the sequence of stimulations was reversed: in this case there was a decrease in amplitude of the testing response to vestibular stimulation. The degree of these reductions depended upon the time-interval elapsed between the afferent stimulations. The maximal degree of depression was observed at 4-6 ms time-interval for conditioning vestibular stimulation and at 10-12 ms time-interval for conditioning radial nerve stimulation. It appears, therefore, that somatosensory and vestibular signals may modulate the activity of trigeminal motor units innervating masticatory muscles, suggesting that extratrigeminal afferents may control the contraction of these muscles.

[Fever of unknown origin in the elderly of the 90's]. / La febbre di origine sconosciuta nell'anziano degli anni '90.

MATERIALS AND METHODS: Eighteen elderly patients (mean age 76.3 +/- 6.9 years) with fever of unknown origin (FUO) are studied sequentially and prospectively from January 1994 to December 1996. The classic Petersdori's criteria of FUO are no more valid for the elderly. The fever of more than 3-4 weeks duration is the only criterion to be considered, the fever is frequently under 38.5 degrees C and the elderly patient is often studied for more than 1 week outside the hospital. RESULTS: The most frequent underlying conditions were: malignancies in particular haematological diseases, followed by multisystem diseases and infections, tuberculosis "in primis". CONCLUSIONS: Selected investigations directed to the most frequent underlying conditions of FUO in the aged individuals overcome the financial cost and the patient discomfort of the tests since an identified curable disease can improve the life expectancy and quality.

Trigeminal motoneuron responses to vestibular stimulation in the guinea pig.

Experiments performed in the guinea pig were aimed at evaluating the effect of electric or caloric stimulations of the vestibular afferents on the electrical activity of the jaw-closing and jaw-opening trigeminal motoneurons. Results showed that masseter and digastric motoneurons mainly responded to vestibular ampullar activation with excitatory responses, with latencies being shorter for contralateral than ipsilateral ampullar stimulation. Differences in latencies between the jaw-closing and jaw-opening trigeminal motoneurons were observed: the masseter motoneurons constantly responded about 2 msec earlier than the digastric motoneurons. These results suggest that the vestibular-trigeminal relationship is quite complex and uses multiple systems to connect the vestibular apparatus with the trigeminal motor nuclei. From the functional point of view, the vestibular-trigeminal relationship may play a role in the dynamic control of the jaw muscle tone during head movements.

Vestibular and somatosensory afferents modulate masseter muscle activity.

The aim of the research was to investigate whether somatosensory impulses starting from the forelimbs could modulate masseter muscle activity in anesthetized guinea pigs. The effect of interactions between radial nerve and vestibular stimulations on the masseter motor unit responses was also studied. Results show that electrical stimulation of both radial nerves induces responses in the masseter motor units most frequently characterized by excitation at latency ranging from 14 to 29 ms. The radial nerve responses were strongly reduced by conditioning electrical stimulation of the vestibular ampullar receptors. Similarly, the vestibular responses were reduced by conditioning radial nerve stimulation. The natural activation of the vestibular macular receptors can either decrease or increase the masseter motor unit responses evoked by electrical stimulation of the radial nerve. These complex inhibitory-excitatory interactions between the two sensory inputs could control the masseter postural tone in relation to the head and limb positions in space.