The association between Occlusion Time and Temporomandibular Disorders

Introduction: Recently, some published studies show there is a multifactorial origin for Temporomandibular Disorders, but the dental occlusion's contribution to the development of Temporomandibular Disorders, and how it may influence the adaptive capacity of the Stomatognathic system, it's still unclear. The aim of this study is to evaluate the correlation between the Occlusion Time and Temporomandibular Disorders. Methods: A total of 54 patients were enrolled in the study (24 males and 30 females, mean age 27.94±8.21years). The TMD group (8 males and 10 females) consisted of subjects who presented with at least 1 of the following signs of Temporomandibular Disorders: Temporomandibular Joint sounds (clicking or crepitation), Temporomandibular Joint locking episodes, limited mandibular opening, painful limitation of mandibular movements, pain to palpation of the Temporomandibular Joint or of the masticatory muscles. The control group (16 males and 20 females) presented as free from Temporomandibular Disorders. The T-Scan III computerized occlusal analysis system was to record the subjects' Occlusion. Times during eight mandibular opening-closing movements. Results: The two-ways ANOVA test analyzed the variations for group and sex, showing that the TMD group mean Occlusion Time (0.64±0.21s) was statistically significantly longer than the control group mean Occlusion Time (0.45±0.17s) (p<0.001). Significant differences were also found for gender where the mean OT of female subjects was longer than males one with statistical significance (p-value<0.01). Conclusions: The computerized analysis of the Occlusion Time in patients affected by TMJ problems has to be carefully considered as adjunctive instrumental device

The Birth-Cluster of the Galactic Luminous Blue Variable WRA751

We present the results of NTT/VLT UBV imaging of a 260 square arcmin region containing the Galactic Luminous Blue Variable WRA751, in search for its birth-cluster, i.e. a cluster of young and massive stars spatially and physically associated with it. On the basis of the classical reddening-free parameter Q, we have identified a sample of 24 early-type stars with colours typical of spectral types earlier than B3. Interestingly, these stars are clustered within a radius of 1 arcmin from WRA751, corresponding to about 1% of the imaged field. These stars tightly distribute around (B-V) = 1.67, which in turn defines a mean extinction A(V) = 6.1 mag. The 5 brighter (V > 16.2) and bluer (Q < -0.9) stars of the sample have been subsequently observed with FORS1 and classified as 3 late O- and 2 early B- stars. The absence of stars earlier than O8 indicates an age of the cluster older than 4 Myr, although it could be due to an incomplete sampling of the upper end of the main sequence. Nevertheless, the detection of OB stars of class I certainly indicates an age of a few million years. At an assumed distance of 6 kpc, we estimate a cluster radius of 3.4 pc and a total mass of 2200 solar masses. Our discovery is only the second known instance of a Galactic Luminous Blue Variable associated with its birth-cluster.Comment: 8 pages, 6 figures, accepted by A&

Mean age gradient and asymmetry in the star formation history of the Small Magellanic Cloud

We derive the star formation history in four regions of the Small Magellanic Cloud (SMC) using the deepest VI color-magnitude diagrams (CMDs) ever obtained for this galaxy. The images were obtained with the Advanced Camera for Surveys onboard the Hubble Space Telescope and are located at projected distances of 0.5-2 degrees from the SMC center, probing the main body and the wing of the galaxy. We derived the star-formation histories (SFH) of the four fields using two independent procedures to fit synthetic CMDs to the data. We compare the SFHs derived here with our earlier results for the SMC bar to create a deep pencil-beam survey of the global history of the central SMC. We find in all the six fields observed with HST a slow star formation pace from 13 to 5-7 Gyr ago, followed by a ~ 2-3 times higher activity. This is remarkable because dynamical models do not predict a strong influence of either the LMC or the Milky Way (MW) at that time. The level of the intermediate-age SFR enhancement systematically increases towards the center, resulting in a gradient in the mean age of the population, with the bar fields being systematically younger than the outer ones. Star formation over the most recent 500 Myr is strongly concentrated in the bar, the only exception being the area of the SMC wing. The strong current activity of the latter is likely driven by interaction with the LMC. At a given age, there is no significant difference in metallicity between the inner and outer fields, implying that metals are well mixed throughout the SMC. The age-metallicity relations we infer from our best fitting models are monotonically increasing with time, with no evidence of dips. This may argue against the major merger scenario proposed by Tsujimoto and Bekki 2009, although a minor merger cannot be ruled out.Comment: 30 pages, 16 figures, accepted for publication in Ap

History and modes of star formation in the most active region of the Small Magellanic Cloud, NGC 346

We discuss the star formation history of the SMC region NGC 346 based on Hubble Space Telescope images. The region contains both field stars and cluster members. Using a classical synthetic CMD procedure applied to the field around NGC 346 we find that there the star formation pace has been rising from a quite low rate 13 Gyr ago to \approx 1.4 \times 10^{-8} Mo yr^{-1}pc^{-2} in the last 100 Myr. This value is significantly higher than in other star forming regions of the SMC. For NGC 346 itself, we compare theoretical and observed Color-Magnitude Diagrams (CMDs) of several stellar sub-clusters identified in the region, and we derive their basic evolution parameters. We find that NGC 346 experienced different star formation regimes, including a dominant and focused "high density mode", with the sub-clusters hosting both pre-main sequence (PMS) and upper main sequence (UMS) stars, and a diffuse "low density mode", as indicated by the presence of low-mass PMS sub-clusters. Quantitatively, the star formation in the oldest sub-clusters started about 6 Myr ago with remarkable synchronization, it continued at high rate (up to 2 \times 10^{-5} Mo yr^{-1} pc^{-2}) for about 3 Myr and is now progressing at a lower rate. Interestingly, sub-clusters mainly composed by low mass PMS stars seem to experience now the first episode of star formation, following multi-seeded spatial patterns instead of resulting from a coherent trigger. Two speculative scenarios are put forth to explain the deficiency of UMS stars: the first invokes under-threshold conditions of the parent gas; the second speculates that the initial mass function (IMF) is a function of time, with the youngest sub-clusters not having had sufficient time to form more massive stars.Comment: 17 pages. Accepted for publication in A

Intersession reliability of a posturo-stabilometric test, using a force platform

To evaluate the intersession reliability of a posturo-stabilometric examination. METHODS: Single blind clinical trial conducted in two sessions over two weeks. 44 healthy volunteers free from postural and temporomandibular disorders. All the subjects complied with the criteria for completing the study. All the subjects underwent two sessions of posturo-stabilometric examinations in different visual and mandibular conditions. Sway area, sway length and the coordinates of the center of pressure were evaluated and statistically analyzed using the Intraclass correlation coefficient (ICC). RESULTS: All the posturo-stabilometric parameters seemed to have an excellent reproducibility with overall ICCs higher than 70% and good confidence intervals except for the sway area (ICC 0.422 with CI 0.283-0.560 with open eyes and ICC 0.554 with CI 0.424-0.683 with closed eyes). CONCLUSIONS: The posturo-stabilometric examination carried out using a force platform has a good intrasession and intersession reliability, especially considering sway velocity, COP X and COP Y parameters. The force platform usefulness in analyzing static posture is confirmed in any medical field

Factors contributing to defaulting scheduled therapy sessions by caregivers of children with congenital disabilities

Background: Defaulting scheduled rehabilitation therapy may result in increased adverse outcomes such as permanent disability and increased healthcare costs. Concomitantly, there is evidence to suggest that early and continued rehabilitation of children with congenital disabilities can improve outcomes significantly. This study was conducted to determine factors contributing to caregivers’ defaulting scheduled rehabilitation  therapy sessions.Methods: A descriptive cross sectional study was carried out at Chitungwiza Central Hospital, a tertiary facility offering in and outpatient rehabilitation services in Zimbabwe. Caregivers of children who had congenital disabilities (N=40) and who had a history of defaulting treatment but were available during the data collection period responded to an interviewer administered questionnaire. Data were analysed for means and frequencies using STATA 13.Results: Factors that contributed to caregivers defaulting scheduled therapy included economic constraints (52%), child related factors (43%), caregiver related factors (42%), service centred factors (30%) and psychosocial factors(58%). Majority of the caregivers (98%) were motivated to attend therapy by observable improvements in their children. Other motivators were incentives given in the rehabilitation department (45%), availability of rehabilitation personnel to provide the required services (48%) and psychosocial support from fellow caregivers, families and the rehabilitation staff (68%). Although all the caregivers could not distinguish occupational therapy from physiotherapy services they all reported that therapy was important.Conclusions: A combination of psychosocial, economic, child centred and service centred factors contributed to caregivers defaulting scheduled therapy. Interventions that may potentially improve caregiver attendance to scheduled therapy include community outreach services, efficient rehabilitation service provision at the hospitals, and facilitation of income generating programmes for caregivers

Influence of activation protocol on perceived pain during rapid maxillary expansion

To investigate the influence of two different activation protocols on the timing and intensity of pain during rapid maxillary expansion (RME)

Hubble Space Telescope faint object camera instrument handbook (Post-COSTAR), version 5.0

The faint object camera (FOC) is a long-focal-ratio, photon-counting device capable of taking high-resolution two-dimensional images of the sky up to 14 by 14 arc seconds squared in size with pixel dimensions as small as 0.014 by 0.014 arc seconds squared in the 1150 to 6500 A wavelength range. Its performance approaches that of an ideal imaging system at low light levels. The FOC is the only instrument on board the Hubble Space Telescope (HST) to fully use the spatial resolution capabilities of the optical telescope assembly (OTA) and is one of the European Space Agency's contributions to the HST program