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This study aimed to propose appropriate management for odontogenic chronic rhinosinusitis.
Thirty-one adult patients with odontogenic chronic rhinosinusitis undergoing maxillary extraction were retrospectively analysed. Patients with (n = 21) and without (n = 10) oroantral fistula on computed tomography were classified. Functional endoscopic sinus surgery was performed when sinusitis did not improve after extraction. The critical indicators for surgical requirement in the management of odontogenic chronic rhinosinusitis were analysed.
Sinusitis significantly improved after extraction in both groups. Patients without oroantral fistula had significantly more severe remnant sinusitis than those with oroantral fistula after extraction on computed tomography (p = 0.0037). The requirement for functional endoscopic sinus surgery was statistically significant for patients without orofacial fistula over those with orofacial fistula (p < 0.0001). The surgical improvement ratio was 93 per cent.
The absence of oroantral fistula and severe sinusitis can be critical indicators for the requirement of functional endoscopic sinus surgery after extraction in the management of odontogenic chronic rhinosinusitis.
In forming procedure of the micro grooves in the flat micro-groove heat pipe, the tie rod is often observed to be broken and the multi-tooth cutter is damaged due to the sharp increase of the ploughing-pulling pressure. This paper theoretically analyzes the factors affecting the capillary heat transferring limit of the micro-groove heat pipe, and simulates the machining process using finite element to acquire the best processing parameters: the squeeze angle is 120°, the drawing depth is 0.25mm, and the ploughing-pulling velocity is 100mm/s. Then these parameters are verified by real manufacturing experiments. The experimental results show that the ploughing-pulling pressure of the micro-groove forming process is close to the strength limit of the rod or multi-tooth cutter, and the process makes little swarf during work. Thus, only using the appropriate machine tool parameters, forming parameters and forming methods can make the wicking structure of flat micro-groove micro-heat pipe with the best heat transferring performance.
The Carboniferous lungfish genus Sagenodus is reviewed from all available British specimens and described in detail for the first time. We identify two species exclusive to the UK: Sagenodusinaequalis, the type species, deriving from the late Carboniferous (=Pennsylvanian); and Sagenodus quinquecostatus derived from the early Carboniferous (=Mississippian). The genus is probably the most widespread of the known Carboniferous lungfish genera, but the British species have not been formally described since their discovery in the mid–late 19th Century. This work will provide data to help resolve existing questions about the position of Sagenodus in the phylogeny of Palaeozoic lungfishes, and provide a template for the recognition of isolated elements in museum collections and the finds from recent and future field work. The early Carboniferous species, S. quinquecostatus, shows a so far unique functional mechanism in which the lower tooth plates appear to rotate relative to the upper plates during jaw closure, implying a kinetic function at the symphysis or jaw joint.
We studied the temporal and spatial variation of diet and oral health of human populations that inhabited the central region of Argentina during the Late Holocene (4000–300 BP) by evaluating isotopic data (δ13Ccol, δ15N), physiological stress indicators (tooth wear), and infectious dental diseases (caries). The sample of 49 individuals was recovered from archaeological sites located in the province of Córdoba, dated by AMS on collagen to a range of 4058 ± 89 years BP to 370 ± 15 14C years BP. After calculating the prevalence of caries and the average dental wear, we compared these values based on regional origin (central highlands and eastern lowlands), temporal assignation (early Late Holocene, late Late Holocene), and sex (female and male). We found clear regional and temporal differentiation, which we interpret as resulting from differential use of plant resources among the regions and a slight deterioration in oral health in the Late Holocene. Stable isotope analysis indicates food consumption of C3 and C4 resources, although the observed temporal variations in the isotopic values may indicate an introduction of C4 resources in the later Late Holocene, mainly in the mountainous region.
To discuss the reasons for misdiagnosis of supernumerary nasal teeth.
Clinical data of four supernumerary nasal tooth patients were analysed retrospectively at visits to our otolaryngology department between 2005 and 2018.
All four patients were male and had a supernumerary nasal tooth in the right nasal cavity. Three of the four patients had previously been misdiagnosed. All the supernumerary nasal teeth were surrounded by granulation tissue or hypertrophic nasal mucosa, and were subsequently confirmed by computed tomography and endoscopy. The granulation tissue or hypertrophic nasal mucosa was removed using microwave ablation, and the supernumerary nasal teeth successfully removed by endoscopy.
Supernumerary nasal teeth are rare, and are usually misdiagnosed because such teeth are surrounded by hypertrophic nasal mucosa or granulation tissue. They can be confirmed by computed tomography and endoscopy.
Cet article présente le processus de traduction en français du Charcot-Marie-Tooth Disease Pediatric Scale (CMTPedS), le seul outil de mesure validé évaluant la sévérité de la maladie chez les enfants atteints de CMT. Le processus de traduction utilisé s’inspire des lignes directrices de la Food and Drug Administration (FDA). La version préliminaire francophone du CMTPedS a été testée auprès de 14 enfants atteints. Les résultats de l’application démontrent que la passation a été bien tolérée par les enfants et s’est avérée conviviale pour les cliniciens. La disponibilité de cet outil en français semble prometteuse pour le suivi des enfants atteints et la réalisation d’essais clinique.
In temperate latitudes sheep have a seasonal reproductive behaviour, which imposes strong constraints on husbandry in terms of work organization and availability of animal products. During the last 50 years, researchers have focused on understanding the mechanisms driving small ruminants’ reproduction cycles and finding ways to control them. This characteristic is inherited from their wild ancestor. However, the history of its evolution over the 10 millennia that separates present day European sheep from their Near Eastern ancestors’ remains to be written. This perspective echoes archaeologists’ current attempts at reconstructing ancient pastoral societies’ socio-economical organization. Information related to birth seasonality may be retrieved directly from archaeological sheep teeth. The methodology consists of reconstructing the seasonal cycle record in sheep molars, through sequential analysis of the stable oxygen isotope composition (δ18O) of enamel. Because the timing of tooth development is fixed within a species, inter-individual variability in this parameter reflects birth seasonality. A review of the data obtained from 10 European archaeological sites dated from the 6th to the 3rd millennia BC is provided. The results demonstrate a restricted breeding season for sheep: births occurred over a period of 3 to 4 months, from late winter to early summer at latitudes 43°N to 48°N, while a later onset was observed at a higher latitude (59°N). All conclusions concurred with currently held expectations based on present day sheep physiology, which, aside from the historical significance, contributes to the reinforcing of the methodological basis of the approach. Further study in this area will permit regional variability attributable to technical choices, within global schemes, to be fully reported.
We investigated age estimation of persons using 45 Japanese human teeth that consisted of mainly the third molar. We measured the radiocarbon content in tooth enamel hydroxyapatite from the crown as well as those in collagen and bioapatite in the root of the same tooth. Age estimations from tooth enamel apatite yielded an absolute age shift of 1.7±1.4 yr from the true age. This value suggests that estimating the age of Japanese people from tooth enamel is as accurate as the previous studies conducted in Europe and the USA. The 14C analysis of roots suggested that bioapatite is formed slightly later than collagen in the same tooth roots. The appropriate formation age ranges suggested by the tooth enamel analysis can be optimized and confirmed by using the additional F14C values of the root samples. We also noticed a characteristic trend of enamel δ13C values in comparison with the formation ages of the crowns of the teeth. The δ13C value tends to increase gradually from –13.0‰ to –11.5‰ from the 1960s to the 1970s, probably being caused by changes in the Japanese diet. This trend may support the selection of proper tooth formation age as supplemental data in addition to 14C content analyses.
The relative spatial position of each chain link and the phase angle of engaged tooth are not concerned in traditional sprocket designs. As such, the chain shifting might fail regularly. In this study, an optimized path of one chain for up-shifting is derived. Such path is formed by several bended chain links sustain yaw and roll. Empirically, appropriate bending, yaw and torsion angles for tooth chamfer, could be shorten the up-shifting distance and phase angle required, eventually facilitate not only more ascending points compactly arranged on sprocket but larger chain laterodeviation which curtails sprockets clearance and integrates the sprocket unit. Then again, the optimized shifting path promotes efficiency and decreases required movement yielded by derailleur tappet pressure.
Angstrom resolution images of human tooth enamel (HTE) crystallites were obtained using aberration-corrected high-resolution transmission electron microscopy and atomic-resolution scanning transmission electron microscopy in the modes of bright field, annular dark field, and high-angle annular dark-field. Images show that the central dark line (CDL) defect observed around the center of the HTE crystals is a site for caries formation in the HTE and has a thickness of ~0.2 nm. Results also suggest that the CDL goes through one of the OH− planes.
Despite evidence for the effects of metals on neurodevelopment, the long-term effects on mental health remain unclear due to methodological limitations. Our objective was to determine the feasibility of studying metal exposure during critical neurodevelopmental periods and to explore the association between early-life metal exposure and adult schizophrenia.
We analyzed childhood-shed teeth from nine individuals with schizophrenia and five healthy controls. We investigated the association between exposure to lead (Pb2+), manganese (Mn2+), cadmium (Cd2+), copper (Cu2+), magnesium (Mg2+), and zinc (Zn2+), and schizophrenia, psychotic experiences, and intelligence quotient (IQ). We reconstructed the dose and timing of early-life metal exposures using laser ablation inductively coupled plasma mass spectrometry.
We found higher early-life Pb2+ exposure among patients with schizophrenia than controls. The differences in log Mn2+ and log Cu2+ changed relatively linearly over time to postnatal negative values. There was a positive correlation between early-life Pb2+ levels and psychotic experiences in adulthood. Moreover, we found a negative correlation between Pb2+ levels and adult IQ.
In our proof-of-concept study, using tooth-matrix biomarker that provides direct measurement of exposure in the fetus and newborn, we provide support for the role of metal exposure during critical neurodevelopmental periods in psychosis.
A non-surgical approach for managing rhinosinusitis associated with chronic oroantral fistula resulting from tooth extraction was evaluated.
Twenty-six consecutive patients (15 males and 11 females) aged 28–72 years (mean, 49.81 years) were administered local decongestion therapy for 2 weeks and antibiotics for 10 days. Patients showing a reduction in Sino-Nasal Outcome Test 22 scores after two weeks continued to receive local decongestion therapy weekly for up to six weeks, while those not showing any improvement underwent surgical management.
At 2 weeks, 17 patients (65.38 per cent) showed an improvement in rhinosinusitis (33.39 per cent mean reduction in Sino-Nasal Outcome Test 22 scores). The primary determinant of response was fistula size. At 6 weeks, sinusitis resolved completely in all 17 patients, and the fistula closed in 16 of these. Final Sino-Nasal Outcome Test 22 and Lund–Mackay scores showed no significant difference between the surgically treated and non-surgically treated groups.
Local decongestion therapy along with antibiotics may promote resolution in this subset of rhinosinusitis patients.
Transoral endoscopic ENT surgical procedures are a mainstay of treatment for a variety of conditions and are often preferable to open surgery where possible. Cases of micrognathia, prominent incisor teeth or trismus may create difficulties in gaining sufficient access to undertake such procedures. Extraction of the anterior maxillary teeth can help overcome these problems in appropriate cases, with subsequent prosthetic tooth replacement supported by dental implants. To date, this approach has not been reported in the literature.
This paper reports on two cases which illustrate this approach; the first case involved pharyngeal pouch management where previous open surgery had failed, and the second case involved glottic carcinoma management where oral access was compromising resection.
This technique is recommended to facilitate effective transoral surgical procedures as a low-morbidity alternative to either open surgery or non-surgical therapies.
To evaluate the correlation among nutritional status, tooth wear and quality of life in Brazilian schoolchildren.
The study followed a cross-sectional design. Nutritional status was measured via anthropometry using BMI and tooth wear was measured using the Dental Wear Index; both these assessments were carried out by a trained recorder according to standard criteria. A modified version of the Child Oral Impacts on Daily Performances was used to assess quality of life.
City of Bauru, in Brazil.
A cluster sample of 396 schoolchildren (194 boys and 202 girls) aged 7–10 years.
The anthropometric assessment showed similar situations for both sexes regarding underweight (31·40 % in boys and 30·20 % in girls) and overweight/obesity (33·96 % in boys and 33·17 % in girls). The underweight children showed a greater severity of tooth wear in the primary teeth (OR=0·72; CI 0·36, 1·42), although in the permanent dentition the obese children had a greater severity of tooth wear (OR=1·42; 95 % CI 0·31, 6·55). The tooth wear was correlated with age for both dentitions.
Tooth wear in the primary and permanent dentition may be related to nutritional status. Tooth wear and obesity did not have a significant impact on the schoolchildren’s perception of quality of life.
This study evaluated the influence of tubular density of different dentin depths and location on the bond strength of high-viscosity glass ionomer cements (GIC). A total of 20 molars were selected and assigned into six experimental groups, considering two different high-viscosity GICs—Fuji IX (FIX) or Ketac Molar (KM), and dentin location—proximal, occlusal superficial, or occlusal deep dentin (n=10). Teeth were cut and a topographical analysis of four sections per group was performed to obtain data about the tubular density of each different dentin location and depths by laser scanning confocal microscopy (100×). Polyethylene tubes were placed over the pretreated surfaces and filled with one of the GICs. Microshear bond strength (µSBS) test was performed after storage in distilled water (24 h at 37°C). Failure modes were evaluated using a stereomicroscope (400×). Multilevel regression analysis was performed to compare the results at a significance level set at 5%. The tubule density was inversely proportional to the bond strength for both GICs (p<0.05). Adhesive/mixed failure prevailed in all experimental groups. Proximal (30036.5±3433.3) and occlusal superficial 29665.3±1434.04 dentin shows lower tubule density, resulting in a better GIC bonding performance (proximal: FIX–3.61±1.05; KM–3.40±1.62; occlusal superficial: FIX–4.70±1.85; KM–4.97±1.25). Thus, we can concluded that the lowest tubule density in proximal and occlusal superficial dentin results in a better GIC bond strength performance.
Various environmental factors have been associated with the timing of eruption of primary dentition, but the evidence to date comes from small studies with limited information on potential risk factors. We aimed to investigate associations between tooth emergence patterns and pre-conception, pregnancy and postnatal influences. Dentition patterns were recorded at ages 1 and 2 years in 2915 children born to women in the Southampton Women’s Survey from whom information had been collected on maternal factors before conception and during pregnancy. In mutually adjusted regression models we found that: children were more dentally advanced at ages 1 and 2 years if their mothers had smoked during pregnancy or they were longer at birth; mothers of children whose dental development was advanced at age 2 years tended to have poorer socioeconomic circumstances, and to have reported a slower walking speed pre-pregnancy; and children of mothers of Asian ethnicity had later tooth development than those of white mothers. The findings add to the evidence of environmental impacts on the timing of the eruption of primary dentition in indicating that maternal smoking during pregnancy, socio-economic status and physical activity (assessed by reported walking speed) may influence the child’s primary dentition. Early life factors, including size at birth are also associated with dentition patterns, as is maternal ethnicity.
Two well-preserved skeletons of Mosasaurus conodon Cope 1881 (Squamata, Mosasaurinae) from the Pierre Shale (late Campanian) of Colorado and the Bearpaw Shale (Late Campanian to Early Maastrichtian) of Montana are described. The two specimens are important because they provide new osteological information, especially on the skull (including jaws with teeth) and forelimbs, whereas those elements are largely missing in the holotype (AMNH 1380) of M. conodon. Morphological comparisons of the holotype with the two new specimens allow us to emend the diagnosis of the species in the genus Mosasaurus, primarily using tooth and forelimb morphologies. Teeth of M. conodon are unique in their combination of having a slender, gently recurved overall shape (similar to Clidastes) with no serration on the developed carinae (less developed in Clidastes). The tooth count of M. conodon tends to be low (14–15 in the maxilla, 16 in the dentary and eight in the pterygoid, respectively) when compared to other species, such as Mosasaurus lemonnieri, Mosasaurus missouriensis and Mosasaurus hoffmanni–Mosasaurus maximus. The forelimb is short in the species, characterised by a much lower number of the manual digital formula, 4(+1?)–4(+2?)–4(+1?)–4(+1)–2 than other species of Mosasaurus. The forelimb bones are generally robust, especially the box-shaped humerus (width-to-length ratio 3/2). A variety of new morphological data support the conclusions that (1) M. conodon is a nominal species, (2) the European species M. lemonnieri is not a junior synonym and (3) one of the most complete skeletons of Mosasaurus from South Dakota (SDSM 452) is not assigned to M. conodon (but is likely to be Mosasaurus sp.). To date, M. conodon occurs only in North America during the late Campanian to early Maastrichtian.
Fossils of megaherbivores from eight late Pleistocene 14C- and OSL-dated doline infillings of Ajoie (NW Switzerland) were discovered along the Transjurane highway in the Swiss Jura. Carbon and oxygen analyses of enamel were performed on forty-six teeth of large mammals (Equus germanicus, Mammuthus primigenius, Coelodonta antiquitatis, and Bison priscus), coming from one doline in Boncourt (~ 80 ka, marine oxygen isotope stage MIS5a) and seven in Courtedoux (51–27 ka, late MIS3), in order to reconstruct the paleoclimatic and paleoenvironmental conditions of the region. Similar enamel δ13C values for both periods, ranging from − 14.5 to − 9.2‰, indicate that the megaherbivores lived in a C3 plant-dominated environment. Enamel δ18OPO4 values range from 10.9 to 16.3‰ with a mean of 13.5 ± 1.0‰ (n = 46). Mean air temperatures (MATs) were inferred using species-specific δ18OPO4–δ18OH2O-calibrations for modern mammals and a present-day precipitation δ18OH2O-MAT relation for Switzerland. Similar average MATs of 6.6 ± 3.6°C for the deposits dated to ~ 80 ka and 6.5 ± 3.3°C for those dated to the interval 51–27 ka were estimated. This suggests that these mammals in the Ajoie area lived in mild periods of the late Pleistocene with MATs only about 2.5°C lower than modern-day temperatures.
Joints of space manipulators are usually simplified as torsional springs in modeling motion equations, and the nonlinear behaviors of the reducer in the joints are generally neglected. In this study, a dynamic model of a space manipulator that considers the joints that are transmitted through a typical 2K-H planetary gear reducer is developed using the Lagrangian method. The backlash clearances, gear tooth profile error, and time-variant meshing stiffness are integrated into the process. The simulation results show that the backlash clearances lead to the accumulation of positioning errors in the space manipulator when the joints rotate back and forth. The tooth profile error is the main cause of severe acceleration fluctuations and meshing force impacts. These fluctuations influence torque instability, which may accelerate gear system failure.
The aim of the research presented is to determine the influence of socio-economic factors in childhood and mid-life on multiple tooth loss and chewing problems in mid- and late life in three Swedish birth cohorts (1903–1910, 1911–1920 and 1921–1925). Longitudinal national Swedish surveys were used for the analysis. Participants were interviewed in mid-life in 1968 and later in life (77–99 years of age) in 2002. Childhood socio-economic positions (SEP) did not result in different odds of multiple tooth loss and chewing problems in mid- and late life, but persons with higher mid-life SEP had lower odds. Persons born into the 1921–1925 birth cohort had significantly lower odds of multiple tooth loss in late life than the 1903–1910 birth cohort. Women had higher odds of losing multiple teeth than men in late life but not mid-life. Neither gender nor childhood and mid-life SEP predicted chewing problems late in life, but older people with multiple tooth loss had higher odds of chewing difficulty than those with mainly natural teeth. Childhood conditions may contribute to multiple tooth loss in mid-life, which subsequently contributes to multiple tooth loss in late life. Tooth loss in late life is strongly associated with difficulty chewing hard food. Prevalence of multiple tooth loss is higher in women than in men in late life but not in mid-life.