bluuebunny/crossref_metadata_2025_split huggingface dataset:
Eccentric anterior wear facets in the diagnosis of temporomandibular disorders
Authors: KIRVESKARI P. , JÄMSÄ T. 
Published: March 2003

The present study aimed at testing whether eccentric anterior bruxing facets are associated with clinical signs from the temporomandibular joints and with palpatory tenderness of the muscles of mastication. Wear facets in the canine and incisor areas were assessed by inspecting dental stone casts made at baseline and at the end of a 4‐year clinical trial involving 129 adolescents and young adults. The subjects who showed distinct increase in wear were divided into three groups: (i) wear pattern indicating an anterior thrust of the working side mandible, (ii) wear pattern indicating a posterior thrust of the working side mandible and (iii) other wear patterns. The assessment of wear patterns was made without knowledge of clinical signs of temporomandibular disorders (TMD). The eventual change in muscular or joint signs of TMD from baseline to the final examination was then obtained from the records, and the association with wear pattern was calculated.There was no significant evidence of an association between eccentric anterior wear and signs of TMD. The direction of the mandibular thrust generated by bruxing was also unassociated with the presence of TMJ and muscular signs. In conclusion, the predictive value of eccentric anterior wear facets in young subjects is too low to be helpful in the diagnosis of TMD.
In vivo horizontal forces on implants depending on the type of occlusion
Authors: MORNEBURG T. , PROESCHEL P. 
Published: March 2003

Minimizing horizontal forces on implants is one of the important aims of an occlusal design. Therefore, several proposals have been made in literature, e.g. flat cuspal slopes or narrow occlusal surfaces. Our aim was to test how these occlusal designs would influence horizontal forces.Ten healthy subjects with unilateral partially edentulous arches were provided with fixed partial dentures (FPD) on two ITI‐implants. The opposing jaw was fully dentate. After an adaptation of 6 month measurement setups with a measuring FPD were put into the mouth. The sensoring device, which consisted of two abutments equipped with strain gauges, evaluated the forces in three dimensions. For each person three FPDs were made with a different design of the occlusal surface. The first FPD exhibited cusps with steep slopes (S), the second showed flat cusps (F) and the third had a narrow occlusal surface (N). The peak forces of the chewing cycles of each patient were evaluated. While chewing wine gum the average values of the vertical forces of the three different FPDs showed no significant differences and amounted to between 253·8 N (s.d. 85·7 N) and 273·9 N (s.d. 63·7 N). With the first FPD (S) mean horizontal forces of 47·9 N (s.d. 34·8 N) were found whereas with the flat surface an average force of 47·4 N (s.d. 37·1 N) was measured. The narrow occlusal surface was associated with an average reduction of the horizontal forces of about 50·9% to a mean value of 24·4 N (s.d. 10·6 N) (P < 0·005). The inclination of occlusal slopes did neither affect vertical nor horizontal forces significantly. However, narrowing of the occlusal surface in the oro‐vestibular direction by 30% showed a significant reduction of the lateral forces exerted on the implants by more than 50%. A reduced oro‐vestibular width of the occlusal surface is recommended especially for diameter‐reduced implants, in case of an unfavourable relationship between implant and crown length or for implants that are strongly inclined to the occlusal plane.
Maximal bite force and EMG during bilateral and unilateral clenching
Authors: VAN DER BILT A. , ABBINK J. H. , FONTIJN‐TEKAMP F. A. , BOSMAN F. 
Published: March 2003

The observed maximal bite force is known to depend on the measuring method employed. Bite position, bite rise and unilateral or bilateral biting influence the observed bite force. The maximal bite force obtained when clenching unilaterally is smaller than the bite force summed for the two sides of a bilateral measurement (Bakke et al., 1989). We determined bite force and muscle activity of the masseter and temporal muscles during maximal voluntary contraction in a group of 81 dentate subjects. The bite force was measured between the first molars both bilaterally and unilaterally. The summed bite force obtained from the bilateral measurement was 569 ± 170 N. The bite force obtained for unilateral clenching was significantly lower: 430 ± 142 N. No significant differences in bite force between the right and left side for both the bilateral and unilateral measurements were observed. The muscle activity of the masseter and temporal muscles obtained from bilateral clenching did not differ significantly (masseter: 248 ± 149 μV and temporalis: 232 ± 105 μV). Also no significant differences were observed in muscle activity between the right and left side during bilateral clenching. We observed a significantly lower muscle activity in both masseter and temporalis for unilateral clenching as compared with bilateral clenching. The results of unilateral clenching showed no differences in muscle activity between the ipsi‐ and contralateral side for the masseter muscle (186 ± 127 μV). However, the muscle activity at the ipsilateral side of the temporal muscle (197 ± 127 μV) was significantly higher than at the contralateral side (150 ± 81 μV). We may conclude that bilateral clenching yields bite forces that are over 30% larger than those obtained during unilateral clenching. The muscle activity during unilateral clenching is symmetrical in the masseter muscles, but asymmetrical in the temporal muscles.
Validation of diagnostic criteria for sleep bruxism
Authors: BABA K. , HAKETA T. , AKISHIGE S. , FUEKI K. , OHYAMA T. 
Published: March 2003

Several diagnostic criteria for bruxism can be taken from the literature; however, most of them have never been validated. This study examined whether predictor variables taken from physical examinations and questionnaires were related to the actual bruxism levels.Fifty dental students agreed to participate in this study and eight examination variables and seven questionnaire variables were collected from them. The subjects measured their nocturnal EMG activity from the right masseter muscle for six consecutive nights in their home by means of a portable EMG device. Off‐line analysis was performed on data from second to sixth nights. By using a custom made software, all EMG activity elevations above a minimum threshold of 50% of each subject's individually established maximum voluntary contraction (MVC) level were quantified with regard to the duration and number of elevations and then three outcome variables, which were event number per hour (number/h), event duration per hour (duration h−1), and duration per event (duration/event), were calculated. A multiple stepwise regression (MSR) analysis was conducted to assess the 15 predictor variables and the three outcome variables. These MSR analyses revealed that the joint sound score remained in the regression equation as a predictor (n=50, P < 0·05) of the likelihood that a subject would exhibit longer bruxism events (duration h

−1

and number h

−1

). It must be noted that the self‐awareness and tooth attrition status were found not to be strong predictors and even for the above variable where significant association was found, the likelihood ratio between the variable and predicted outcomes was not robust.
Interactions between swallowing centre, chewing centre and supramedullary region during elicitation of swallows by superior laryngeal nerve (SLN) stimulation
Authors: YAMADA Y. , YAMAMURA K. , TAKAGI M. , AMARASENA J. K. C. 
Published: March 2003

Swallowing centre (swl‐c) which controls motor behaviour of swallowing receives inputs from other regions including respiratory center, chewing center (chw‐c) and supramedullary region. However, interactions between them are unclear. The objective of this study was to elucidate such interactions using freely behaving six domestic male rabbits. Swallows were elicited by superior laryngeal nerve (SLN) stimulation. The electromyographic activities (EMGs) of masticatory and swallowing muscles and the jaw movement orbits were recorded for 30 s with and without SLN stimulation at rest and during chewing. Decerebration was performed to investigate the influence of supramedullary region. Although there was a significant increase (P < 0·001) in the number of swallows between with and without SLN stimulation at rest and during chewing, the absolute increase in the number of swallows was same. After decerebration, the number of swallows was decreased significantly (P < 0·05). There were no significant differences in the latency of thyrohyoid EMG onset and cycle durations between with and without SLN stimulation. It is concluded that (i) swallows induced by SLN stimulation may be identical to those induced by food bolus, (ii) generation of swallows by swl‐c might be controlled by chw‐c, (iii) swl‐c might affect the rhythm generator in chw‐c and (iv) supramedullary region might send a tonic excitatory input to swl‐c and maintains its excitability. Supported by Japan grants – in‐aid #1470389 and #12771102.
Possible gender‐related differences in a jaw reflex evoked by stimulation of the human lip
Authors: LYONS M. F. , OKDEH A. M. , CADDEN S. W. 
Published: March 2003

It has been reported that the latency of the jaw jerk reflex in symptom‐free human female subjects is significantly shorter than in male subjects (Kossioni et al., 1994). In the present study, we have begun to investigate whether there are any gender‐related differences in other jaw reflexes. The EMG recordings were made from an active masseter muscle in 16 young adult age‐matched subjects (eight male, eight female; aged 20–43 years). Inhibitory reflexes were evoked in the muscle by applying stimuli through bipolar electrodes clipped over the lower lip with the cathode placed intraorally on the oral mucosa. While the stimuli were being applied, the subjects maintained the EMG level at around 10% of maximum with the aid of visual feedback. The presence or absence of reflex responses was determined as previously described (Louca et al., 1996). Wilcoxon Rank Sum tests were used to compare the properties of the short‐ (∼10–15 ms) and long‐ (∼40–50 ms) latency inhibitory reflexes evoked by the stimuli in the two groups. There was no significant difference between the male and female groups in the threshold or latency of either reflex. However, the duration of the long‐latency inhibition was significantly shorter in females than in males (median values: 29·0 versus 44·0 ms, P=0·015). These preliminary findings suggest that, at least in young human subjects, there is a gender‐related difference in the strength but not in the presence of long‐latency inhibitory jaw reflexes.
Discourses on empowerment
Authors: Tilley  , Pollock  , Tait  
Published: March 2003

The discourse community of British psychiatric and mental health nursing is a contested realm. The ‘Big Stories’ of policy and planning of services are clearly articulated in disputes in journals, but the ‘Little Stories’ of nurses’ work and patients’ or users’ experiences may be ignored or under‐valued. This paper illustrates how the Big Story of a central theme in current policy – empowerment – is articulated in the realm of research funding and design, and how it is articulated by practitioners. The paper focuses attention on the responsibilities faced by researchers, in relating the Little Stories of practice and the Big Story of policy. It reports early and tentative findings from a study of community psychiatric nurses’ empowerment of people with enduring mental disorders. The paper suggests ways in which strategies for analysis of qualitative data from interviews with CPNs may be informed by ideas drawn from the field of discourse analysis; reflexively examining how researchers’ discourses relate to those of policy makers and mental health nursing practitioners.This paper is based on a presentation at the Network for Psychiatric Nursing Research Conference, Napier University, Edinburgh, 17 September 1997.
Respiratory‐related evoked potentials during the transition from alpha to theta EEG activity in Stage 1 NREM sleep
Authors: Gora John , Colrain Ian M. , Trinder John 
Published: March 2003

SummaryIt has been argued previously that evoked potential components during Stage 1 sleep in response to both auditory and respiratory stimuli are intermediate between those of wakefulness and Stage 2 sleep. However, state fluctuations in the EEG between alpha and theta during Stage 1 sleep have been linked to changes in a number of respiratory functions including ventilation, upper airway resistance and chemical drive. It was therefore hypothesized that if respiratory related evoked potentials (RREP) were averaged separately for alpha and theta EEG periods during Stage 1 sleep, the alpha RREP would resemble wakefulness and the theta RREP would resemble Stage 2 sleep. RREPs were produced by 250 ms occlusions in 10 subjects. EEG was recorded from 29 scalp sites, referenced to linked ears, together with EOG and EMG. The N1 component was not specifically associated with alpha vs. theta activity, but appeared to be sensitive to any decrease in arousal level, suggesting that it was more related to attention than to changes in the EEG. The late N2 and P300 components were present during wake and Stage 1 alpha. However, in Stage 1 theta, different late components emerged (N300 and P450) that differed in latency, amplitude or topographical distribution from those seen in wakefulness. The P2 proved difficult to interpret, whereas the N550 did not appear until Stage 2 sleep, and as such, was not dependent on alpha/theta state. The results indicate that RREP components are differentially affected by the transition into sleep.
The effect of clustered versus regular sleep fragmentation on daytime function
Authors: Martin Sascha E. , Brander Pirkko E. , Deary Ian J. , Douglas Neil J. 
Published: March 2003

SummaryPreviously, we found that regular sleep fragmentation, similar to that found in patients with sleep apnoea/hypopnoea syndrome (SAHS), impairs daytime function. Apnoeas and hypopnoeas occur in groups in patients with REM or posture related SAHS. Thus, we hypothesised that clustered sleep fragmentation would have a similar impact on daytime function as regular sleep fragmentation. We studied 16 subjects over two pairs of 2 nights and 2 days. The first night of each pair was for acclimatisation. On the second night, subjects either had their sleep fragmented regularly every 90 s, or fragmented every 30 s for 30 min every 90 min, the remaining 60 min being undisturbed. We fragmented sleep with tones to produce a minimum 3 s increase in EEG frequency. During the days following each pair of nights we tested subjects daytime function. Total sleep time (TST) and microarousal frequency were similar on both study nights. We found significantly less stage 2 (55 SD 4, 62±7%; P=0.001) and more slow wave sleep (21 SD 3, 12±6%; P < 0.001) on the clustered night. Mean sleep onset latency was similar on MSLT (clustered 10 SD 5, regular 9±4 min; P=0.7) and MWT (clustered 32 SD 7, regular 30±7 min; P=0.2). There was no difference in subjects mood or cognitive function after either study night. These results suggest that although there is more slow wave sleep (SWS) on the clustered night, similar numbers of sleep fragmenting events produced similar daytime function whether the events were evenly spaced or clustered.
Effect of infant sleeping position on sleep spindles
Authors: Horne Rosemary S. C. , Egodagamage Chamali , Cranage Susan M. , Adamson T. Michael 
Published: March 2003

SUMMARYSleep spindles play an active role in inducing and maintaining sleep and may affect arousal by blocking the transmission of external stimuli through the thalamus to the cortex. Previously we have demonstrated that sleeping in the prone position impairs arousal in infants at 2–3 months of age, but not at 5–6 months. We aimed to examine if sleeping position and postnatal age affected duration and/or density of sleep spindles. Twenty‐one healthy term infants were studied using daytime polysomnography at 2–3 months and 16 were again studied at 5–6 months. Infants slept both prone and supine at each study. The mean duration of non‐rapid eye movement (NREM) sleep was not different between the two studies in either position. At 2–3 months both spindle density (P < 0.001) and proportion of NREM sleep (P < 0.025) with spindles were significantly greater in the supine than in the prone position. At 5–6 months spindle duration was longer in the supine than in the prone position (P < 0.03). Spindle density in the supine position was not different between the two studies, however, when infants slept prone, it was significantly increased at 5–6 months compared with 2–3 months (P < 0.001). Arousal threshold was not correlated with either spindle density or percentage of NREM sleep with spindles in either position at either study. In this study spindle density and the percentage time spent with spindles were not well correlated with infant arousability, and hence may not be able to be used as markers of depressed arousal responses in infants.
Pharmacological and pathophysiological modulation of food intake and forestomach motility in small ruminants
Authors: Van Miert  , Van Duin  
Published: March 2003

I IntroductionII Pharmacological modulation of food intake and forestomach motilityII 1. Orexigenic agents1.1 glutamate1.2 benzodiazepines1.3 opioid receptor agonists and antagonists4 neuropepetides Y (NPY)II 2. Anorectic agents2.1 cholecystokinin (CCK) agonists and antagonists2.2 serotonin receptor agonists and antagonists2.3 dopamine receptor agonists and antagonists2.4 alpha‐2 adrenoceptor agonists and antagonistsIII Anorexia and ruminal stasis during the Acute Phase Response to infections1. cytokines2. prostaglandins3. hormones4. nitric oxideIV ConclusionsV References
Pharmacokinetics, metabolism and urinary detection time of flunixin after intravenous administration in camels
Authors: Wasfi I.A. , Boni N.S. , Abdel Hadi A.A. , ElGhazali M. , Zorob O. , Alkatheeri N.A. , Barezaiq I.M. 
Published: March 2003

The pharmacokinetics of flunixin were determined after an intravenous dose of 1.1 mg/kg body weight in six camels and 2.2 mg/kg body weight in four camels. The data obtained (mean ±  SEM) for the low and high dose, respectively, were as follows: The elimination half‐lives (t½β) were 3.76 ± 0.24 and 4.08 ± 0.49 h, the steady state volumes of distribution (Vdss) were 320.61±38.53 and 348.84 ± 35.36 mL/kg body weight, total body clearances (ClT) were 88.96 ± 6.63 and 84.86±4.95 mL/h/kg body weight and renal clearances (Clr) were 0.52 ± 0.09 and 0.62 ± 0.18 mL/h/kg body weight. A hydroxylated metabolite of flunixin was identified by gas chromatography/mass spectrometry (GC/MS) under electron and chemical ionization and its major fragmentation pattern was verified by tandem mass spectrometry (GC/MS/MS) using neutral loss, daughter and parent scan modes. The detection times for flunixin and its hydroxylated metabolite in urine after an intravenous (i.v.) dose of 2.2 mg/kg body weight were 96 and 48 h, respectively.
A comparison between clenbuterol, salbutamol and terbutaline in relation to receptor binding and in vitro relaxation of equine tracheal muscle
Authors: Törneke  , Ingvast Larsson  
Published: March 2003

Beta2‐adrenoceptor agonists are used as bronchodilators in both humans and horses. Of these drugs, clenbuterol is the one most frequently used when treating chronic obstructive pulmonary disease in the horse, while salbutamol and terbutaline are used in the treatment of human asthma. Little is known of the properties of the latter two drugs in equine medicine. We have compared salbutamol and terbutaline with clenbuterol in relation to their ability to relax muscle strips from equine tracheal muscle, pre‐ contracted with 40 nm carbachol, in tissue chambers. The affinities of these drugs to the β2‐adrenoceptors in homogenates of the same muscle tissue were also examined. These experiments were performed with radioligand binding studies using the very potent β‐adrenoceptor antagonist 125I‐cyanopindolol. The three drugs were almost equipotent in relaxing the muscle strips. The EC50‐values for salbutamol, terbutaline and clenbuterol were 5.6, 13.8 and 2.1 nm, respectively, and all three drugs relaxed the preparations completely. In the competitive binding study, however, the Kd‐value of clenbuterol was much lower (24 nm) than that of salbutamol and terbutaline (1100 nm and 3900 nm, respectively). The amount of receptors bound at the EC50‐value of clenbuterol was 8% compared to less than 1% for salbutamol and terbutaline. This indicates a lower intrinsic efficacy of clenbuterol than of the other two drugs. The β‐adrenoceptor density was 45 ± 14.3 fmol/mg protein (mean ± SD) and the Kd‐value of 125I‐cyanopindolol was 11.4 ± 3.3 pm.
Pharmacokinetics, bioavailability and dosage regimen of sulphadiazine (SDZ) in camels (Camelus dromedarius)
Authors: Kumar  , Singh  , Kapoor  , Rai  
Published: March 2003

The pharmacokinetics of sulphadiazine (SDZ) (100 mg/kg, body weight) were investigated in six camels (Camelus dromedarius) after intravenous (i.v.) and oral (p.o.) administration. Following i.v. administration, the overall elimination rate constant (β) was 0.029±0.001/h and the half‐life (t½β) was 23.14±1.06 h. The apparent volume of distribution (Vd(area)) was 0.790±0.075 L/kg and the total body clearance (ClB) was 23.29±2.50 mL/h/kg. After p.o. administration, SDZ reached a peak plasma concentration (Cmax(cal.)) of 62.93±2.79 μg/mL at a post injection time of (Tmax(cal.)) 22.98±0.83 h. The elimination half‐life was 19.79±1.22 h, not significantly different from that obtained by the i.v. route. The mean absorption rate constant (Ka) was 0.056±0.002 h−1 and the mean absorption half‐life (t½Ka) was 12.33±0.37 h. The mean availability (F) of sulphadiazine was 88.2±6.2%. To achieve and maintain therapeutically satisfactory plasma SDZ levels of 50 μg/mL, the priming and maintenance doses would be 80 mg/kg and 40 mg/kg intravenously and 90 mg/kg and 45 mg/kg orally, respectively, to be repeated at 24 h intervals.
Chronobiological variations of indomethacin pharmacokinetic parameters in sheep
Authors: Boggio J. C. , Valtorta S. E. , Sánchez S. , Mckellar Q. 
Published: March 2003

Boggio, J. C., Valtorta, S. E., Sánchez, S., McKellar, Q. Chronobiological variations of indomethacin pharmacokinetic parameters in sheep.J. vet. Pharmacol. Therap.24,261–265.A two‐phase study to investigate the influence of administration time on pharmacokinetics of indomethacin in sheep was performed. In phase I, 12 animals were allocated to four groups, each corresponding to a different time: 08:00, 14:00, 20:00, 02:00 h. Sheep received an intravenous administration of 1 mg/kg indomethacin. In phase II, each group was administered indomethacin with a 12‐h difference compared to Phase I. The trial was performed in autumn, and animals were subjected to a natural light:dark cycle of 10:14 h. Blood samples were taken and processed by high performance liquid chromatography (HPLC) with ultraviolet detection. For each pharmacokinetic parameter, an analysis of variance was performed to outline the existence of chronobiological variations. Concentration at zero time (C0), hybrid constant for distribution and its half life, hybrid constant for elimination and its half‐life, volume of distribution (Vd), area under the curve (AUC∞) and clearance rate (Cl), presented chronobiological variations (P < 0.05) and were fitted to a cosine equation. The following parameters adjusted to circadian rhythms:C0(acrophase: 13.9788 h);AUC∞(acrophase: 13.4377 h);Vd(acrophase: 0.8245 h) andCl(acrophase: 1.4965 h). It was concluded that pharmacokinetic parameters of intravenously injected indomethacin in sheep would behave in a different, though predictable, manner according to the animal’s biological clock.