Mutation analysis and expression of the mottled gene in the macular mouse model of Menkes disease

OBJECTIVES: The purpose of this study was to evaluate the ability of two different panoramic imaging systems to produce cross-sectional images with accurate vertical dimensions of the posterior mandible. STUDY DESIGN: Three partially edentulous human cadaver mandibles were used for this study. On each mandible, three potential implant sites were arbitrarily identified in an area between the mental foramen and the ascending ramus. Each site was imaged using two different panoramic machines. Using each image, the mandible's outline, cortical thickness, and position of the mandibular canal were traced on clear acetate film. The mandibles were then sectioned at each site to serve as a gold standard. The cadaver sections and tracings (corrected for magnification) were measured, recording the overall mandibular height, distance from the crest of the ridge to the superior aspect of the mandibular canal, and the thickness of the cortical bone at the most inferior aspect of the mandible. RESULTS: There were no significant differences between either of the system's image measures and the gold standard when considering the distance between the crest and the mandibular canal. Differences were noted between the systems measures and the gold standard in the assessment of the cortical bone thickness and the overall mandibular height. CONCLUSIONS: Both imaging systems can be useful for vertical measurements of a potential implant site in the posterior mandible.     

A radiographic analysis of the mandibular canal of the edentulous mandible in different racial and gender groups

Studies on the mandibular canal in the edentulous mandible have rarely been correlated with mandibular canal position, mandibular body width, mandibular canal width, thickness of bony plates, gender and race. The aim of this investigation was to examine the above parameters by studying the bucco-lingual relationship of the mandibular canal in dry edentulous mandibles of Black and White, males and females (n = 13 in each group), of similar age (mean 58, 17 yrs). The mandibles were radiographed cross-sectionally. The position of the mandibular canal in relation to the buccal and lingual cortical plates, and the widths of the mandibular canal and mandibular body, measured at selected distances, were recorded and the values statistically analysed. Race and gender do not seem to influence the position of the mandibular canal in the bucco-lingual plane. The location of the canal is predominantly closer to the lingual cortex in the bucco-lingual plane. It was found that the widths of the left and right halves of the mandibular body are not statistically significantly different but widths of the left and right mandibular canal are significantly different.     

Striatal dopaminergic D1 and D2 receptors after intracerebroventricular application of alloxan and streptozocin in rat

The purpose of this study was to evaluate the changes in condylar position following bilateral sagittal split ramus osteotomy with 5- and 10-mm setback in 1 symmetric human cadaver mandibles. A Plexiglas device was constructed to determine the mandibular morphology and the movements of the condyle and the proximal segments before and after surgery. There was no statistically significant relationship between mandibular morphology or the magnitude of setback and changes in condylar position postsurgery. All condyles and rami tipped in a highly variable fashion in the coronal plane. In the axial plane, the lateral pole of the condyles rotated predominantly anteriorly; the left side rotated significantly more than did the right. In the sample studied, the position of the condylar and proximal segments was altered in a highly variable and unpredictable manner, regardless of the magnitude of setback or the morphology of the mandible.     

Computerized cephalometric evaluation of orthognathic surgical precision and stability in relation to maxillary superior repositioning combined with mandibular advancement or setback

PURPOSE: A computerized, cephalometric, orthognathic surgical program (TIOPS) was applied in orthognathic surgical simulation, treatment planning, and postoperatively to assess precision and stability of bimaxillary orthognathic surgery. PATIENTS AND METHODS: Forty consecutive patients with dentofacial deformities requiring bimaxillary orthognathic surgery with maxillary superior repositioning combined with mandibular advancement or setback were included. All patients were managed with rigid internal fixation (RIF) of the maxilla and mandible and without maxillomandibular fixation (MMF). Preoperative cephalograms were analyzed and treatment plans produced by computerized surgical simulation. Planned, 5-week postoperative and 1-year postoperative maxillary and mandibular cephalometric-positions were compared. RESULTS: In the mandibular advancement group, the anterior maxilla was placed too far superiorly, with an inaccuracy of 0.4 mm. The posterior maxilla and the anterior mandible were placed in the planned positions. The lower posterior part of the mandibular ramus was placed too far anteriorly, with an inaccuracy of 2.0 mm. However, the mandibular condyles were accurately placed. In the setback group, the anterior maxilla was placed too far superiorly and posteriorly, with a vertical and sagittal inaccuracy of 1.0 mm and 0.7 mm, respectively. The posterior part of the maxilla was placed in a posterior position with an inaccuracy of 1.9 mm. The anterior mandible was placed too far anteriorly with an inaccuracy of 0.9 mm. The lower posterior part of the mandibular ramus was placed in a posterior position with an inaccuracy of 0.9 mm. However, the mandibular condyles were accurately placed. The statistical analysis of the 1-year stability data showed that the maxilla had moved 0.3 mm posteriorly in the advancement group and the lower incisors had moved 0.8 mm superiorly. No other significant positional maxillary or mandibular changes were found. In the setback group, the maxilla had moved 0.5 mm posteriorly, the anterior mandible 0.5 mm anteriorly, and the lower incisors 0.7 mm superiorly. No significant positional changes were seen in the mandibular ramus. CONCLUSION: The TIOPS computerized, cephalometric, orthognathic program is useful in orthognathic surgical simulation, planning, and prediction, and in postoperative evaluation of surgical precision and stability. The simulated treatment plan can be transferred to model surgery and finally to the orthognathic surgical procedures. The results show that this technique yields acceptable postoperative precision and stability.     

Adolescent female craniofacial morphology associated with advanced bilateral TMJ disc displacement

The aim of this study was to determine if cephalometric measurement differences occurred between two groups of similarly aged female adolescents which differed with respect to their diagnoses of temporomandibular joint disc position on magnetic resonance images (MRI). One group consisted of 17 female adolescents exhibiting complete bilateral disc displacement affecting the temporomandibular joints (TMJ), while the second group of 17 female adolescents was diagnosed as having bilateral normal disc position on MRI. Independent sample t-tests identified statistically significant differences in cephalometric measurements between the two groups, but no age difference between the two groups was evident. The group with bilateral total disc displacement exhibited the following significant angular differences from the group with normal disc position: an increased mandibular and palatal plane relative to sella-nasion; posterior rotation of the mandible as illustrated by an increased angle between the posterior border of the mandibular ramus and sella-nasion; and a decrease in Rickett's facial axis. Significant differences in linear cephalometric variables were also evident between the two groups. Total posterior facial height and ramus height were reduced in the totally disc displaced group. Furthermore, a slight increase in the middle anterior facial height was noted, with a decrease in the posterior cranial base vertical height in the totally disc displaced group.     

Short-term effects of particulate air pollution on respiratory morbidity in asthmatic children

OBJECTIVE: The aim of this study was to quantify the effect of mandibular angulation, position, and shape of an edentulous mandible on the distortion of its image in panoramic radiographs. STUDY DESIGN: Five edentulous dry mandibles varying in size from small to wide and equipped with metal bars in and on top of the mandible were used. The mandibles were radiographed at nine different positions by tilting the mandible posteriorly around a transversal axis, using an orthopantomograph. RESULTS: The length of the images of the bars on top of the mandible increased significantly by tilting the mandibles from +20 degrees to -20 degrees. The magnification factor of the images of the intrabony bars in the mandible was the largest at 0 degrees and decreased significantly by both decreasing or increasing the inclination. The size of the mandible was not related to the magnification factor. CONCLUSION: For both diagnostic and evaluation purposes of the edentulous mandible, the panoramic radiograph is not a reliable radiographic technique unless meticulous precautions are taken for reproducible positioning of the patient in the apparatus.     

A practice-based randomised controlled trial of the efficacy of an electric and a manual toothbrush on gingival health in patients with fixed orthodontic appliances

Twenty-three specimens from immediately anteroinferior to the mental foramen were obtained from male and female, dentate and edentate, human mandibles. Planoparallel 80 microm thick sections were prepared from the mandibular specimens and computerized quantitative microradiography undertaken, which allowed the production of mineralization frequency distribution curves and mean mineralization. No differences in mean mineralization with age, sex, presence or absence of dentition were found, but mineralization distribution curves indicated differences between males and females. Within the age range and small sample size examined (40-90 years) there were no age-related differences. There was a lower level of mineralization distribution in the edentulous than the dentate mandible.     

The effect of post milking teat dip and suckling on teat skin condition, bacterial colonisation, and udder health

The aim of this study was to investigate whether in the maxilla and in the mandible the structure of the anterior medial sagittal alveolar and basal bone is related to the overbite. A total of 460 untreated adult subjects were divided into four groups with either deep bite, normal overbite, end-to-end bite, or open bite and were compared. The overbite, lower face height, and anterior alveolar and basal midsagittal cross-sectional areas from the maxilla and the mandible were assessed on lateral cephalometric radiographs. An index was calculated, dividing the sagittal by the vertical dimension of the midsagittal cross-sectional area. A deeper bite coincided with smaller lower face height, larger alveolar and basal areas, and a more widened shape of the symphysis. If the lower face height was introduced as a covariable, the open bite group showed significantly smaller maxillary and mandibular alveolar and basal cross-sectional areas compared with the end-to-end group, the normal overbite group, or the deep bite group. Vertical variation of the overbite probably coincides with a relative hyperdevelopment or hypodevelopment of the symphysis.     

Differences between right and left lateral chest radiographs

Differences between 150 normal right lateral chest teleroentgenographs and 150 left laterals (infants, children, and adults) were evaluated and determined to be greater than has been generally appreciated. On the left lateral view the left leaf is distinguished from the right leaf by the following generalizations: anteriorly the left leaf is lower; posteriorly it is higher as is its costrophrenic sulcus; it intersects the relatively flattened right leaf near the posterior heart border; the stomach bubble and/or colon are immediately subjacent; there is no segmental obliteration by the inferior vena cava as there often is with the right leaf; in adults the outline of the left leaf is often sharper. When both major fissures can be identified, the left almost always intersects its diaphragmatic leaf posterior to and more vertically than the right fissure.     

Cross-sectional area of the mandible

PURPOSE: The anatomy of the mandible was examined by measuring the cross-sectional area (CSA) of multiple regions of 10 fully dentulous hemimandibles to provide a better understanding of regional structural differences that may have implications regarding biomechanical strength, surgical reconstruction, and fracture site frequency. MATERIALS AND METHODS: Fifteen cuts from the condyle to the symphysis were made of each hemimandible (n = 150 cuts). A Zeiss Videoplan digitizer was used to determine the CSA. RESULTS: The total CSA through the condyle was greater than the CSA through the condylar neck. The CSA through the ramus exceeded that of the condylar neck. The total CSA of the midramus was significantly greater than that of the upper ramus. The total CSA at the body, parasymphysis, and symphysis was significantly greater than at the mid-angle. The total CSA of the cortex increased anteriorly; these differences become significant between the condylar neck and the body, parasymphysis, and symphysis. The total CSA, and the CSA of the cortex and spongiosa, remained relatively constant from the inferior angle anteriorly. CONCLUSIONS: Significant differences exist in the CSA at different points, with an increase in the total, cortical, and spongiosal CSA anteriorly from the condylar neck to the angle. The total CSA and the CSA of the cortex and spongiosa remain relatively constant anterior to the inferior angle. These data suggest that bony CSA alone is not the sole factor in determining fracture site frequency.     

Assessment of symphysis morphology as a predictor of the direction of mandibular growth

The purpose of this study was to determine whether symphysis morphology could be used as a predictor of the direction of mandibular growth and to assess growth changes of the symphysis. Cross-sectional data included lateral cephalometric radiographs of 115 adults (58 women, 57 men) with the longitudinal sample a subset of 62 subjects (30 females, 32 males) at four age groups. The direction of mandibular growth was evaluated with seven cephalometric measurements that included Y-axis, SN to mandibular plane, palatal plane to mandibular plane, gonial angle, sum of saddle, articulare and gonial angles, percentage lower facial height, and posterior/anterior face height. The mandibular symphyseal dimensions studied were height, depth, ratio (height/depth), and angle. Symphysis morphology was found to be associated with the direction of mandibular growth, especially in male subjects with symphysis ratio having the strongest relationship. A mandible with an anterior growth direction was associated with a small height, large depth, small ratio, and large angle of the symphysis. Conversely, a posterior growth direction was associated with a large height, small depth, large ratio, and small angle of the symphysis. Symphysis dimensions continued to change until adulthood with male subjects having a greater and later occurring change compared with female subjects.     

Periosteal migration in the growing mandible: an animal model

Migration of mandibular periosteum and attached musculature was tracked along the inferior border of the ramus in growing and nongrowing guinea pigs (Cavia porcellus) over a 6-week period. Particulate metallic growth-tracing implants were placed through the bony mandible and adjacent musculature at two anteroposterior locations and two bony reference markers were placed anteriorly. Quantification from weekly radiographs of growing animals showed marked posterior migration of the periosteum, whereas in nongrowing animals there was negligible periosteum movement. Significantly greater migration occurred in posterior (6.37 +/- 0.76 mm) implants relative to the anterior implants (3.45 +/- 0.86 mm, p < 0.001). The neutral zone, where little periosteal migration occurs, was calculated to be approximately at the anteroposterior center of the molar tooth row. Analysis of the orientation of the medial pterygoid muscle relative to the mandible showed that muscle fibers on average become more horizontal. Thus, the study found differential anteroposterior migration of the mandibular periosteum in growing animals and correlative changes in orientation of the medial pterygoid muscle.     

Determinants of happiness and life satisfaction in elderly Zimbabweans

OBJECTIVE: To assess determinants of happiness and life satisfaction in elderly Zimbabweans. DESIGN: Community based cross sectional survey. SETTING: Randomly selected villages and two urban areas in north eastern Zimbabwe. SUBJECTS: 278 subjects aged 60 to 92 years (124 male, 154 female). METHOD: One subject per randomly selected household was interviewed, at home, by a trained interviewer to complete a questionnaire. RESULTS: Independent determinants of happiness were: rural residence, whether children gave material support and satisfaction with financial circumstances. [Adjusted odds ratios and confidence intervals 0.25 (0.13 to 0.49), 0.45 (0.22 to 0.94) and 0.11 (0.01 to 0.87) respectively]. Independent determinants of life satisfaction were: feeling better off than their neighbours, receiving adequate respect from their children and satisfaction with financial circumstances. [Adjusted odds ratios and confidence intervals 0.73 (0.59 to 0.91), 0.13 (0.03 to 0.59) and 0.24 (0.1 to 0.61) respectively]. CONCLUSIONS: We have demonstrated that, despite physical hardship, the majority of Zimbabwean elders are happy and 50% are satisfied with their lives and we have identified independent determinants of happiness and life satisfaction in this group. Characterization of these determinants allows us to predict that social changes such as rural/urban migration, declining family support and diminishing respect from children will have a negative effect on happiness and life satisfaction in our elders. It is important that, when planning intervention programmes for the elderly, these facets of wellbeing are not neglected.     

A gloverin-like antibacterial protein is synthesized in Helicoverpa armigera following bacterial challenge

The elucidation of patterns of cranial skeletal maturation and growth in fossil hominids is possible not only through dental studies but also by mapping different aspects of ossification in both extant African apes and humans. However, knowledge of normal skeletal development in large samples of extant great apes is flimsy. To remedy this situation, this paper offers an extensive survey and thorough discussion of the ossification of the posterior border of the sphenoid greater wing. Indeed, this area provides much information about basicranial skeletal maturation. We investigate three variants: the absence of the foramen spinosum and the position of both the foramen spinosum and the foramen ovale in relation to the sphenosquamosal suture. Providing original data about humans and 1,425 extant great ape skulls and using a sample of 64 fossil hominids, this study aimed to test whether different ossification patterns occurred during the course of human evolution. The incidence of three derived morphologies located on the posterior border of the sphenoid greater wing increases during human evolution at different geological periods. The evolutionary polarity of these three derived morphologies is assessed by outgroup comparison and ontogenetic methods. During human evolution, there is a clear trend for the foramen spinosum to be present and wholly located on the posterior area of the sphenoid greater wing. Moreover, in all the great ape species and in Australopithecus afarensis, the sphenosquamosal suture may split the foramen ovale. Inversely, the foramen ovale always lies wholly within the sphenoid greater wing in Australopithecus africanus, robust australopithecines, early Homo, H. erectus (and/or H. ergaster), and Homo sapiens. From ontogenetic studies in humans, we conclude that, during human evolution, the ossification of the posterior area of the sphenoid greater wing progressively surrounded the middle meningeal artery (passing through the foramen spinosum) and the small meningeal artery (passing through the foramen ovale).     

Recombinant coagulation factors

Sometimes, preoperative planning in dental implantology, based on sufficient alveolar height, cannot be verified due to transversal deficiencies. A total of 102 bony mandibles and 95 maxillae were analysed after classification of atrophy, simulating implant insertion at 518 standardised edentulous cross sections with regard to anterior/posterior, mandible/maxilla and class of atrophy. Furthermore, the relation of alveolar height to possible implant length in 86 patients was evaluated retrospectively. Implant length reduction compared with alveolar height was necessary in 10% (mandibles) and 7.5% (maxillae) of the bony-jaw sections and 52.5% (mandibles) and 41.5% (maxillae) of the patients' implant regions. In this respect, the class of atrophy of the bony jaws was more important than the region of simulation. However, the highest differences were observed between mandibles and maxillae, both clinically and experimentally: simulation was possible in all mandibles and 42.5% of the maxillae, but clinical implantation was only possible in 86% of 62 mandibles and 0% of 24 maxillae, mostly due to reduced alveolar height. Alveolar ridge width primarily affected the possible implant lengths. Nevertheless, in four (two mandibular and two maxillary cases) of 58 patients (7%) with sufficient height, a surgical procedure that had already been started had to be stopped. It is expected that cross-sectional radiographical techniques of implantation planning, including ridge-width determination, will gain importance in the future.     

Obesity: is it a problem in black Africans in Zimbabwe?

The body mass indices (BMIs) and waist: hip (W:H) ratios of 1,509 Black Africans were assessed to determine whether or not obesity is a problem in this population, as this information is scanty. Measurements of weight, height, waist and hip circumferences were done in three provinces of Zimbabwe, sampling rural and urban dwellers separately. The results showed that the ranges of BMIs and W:H ratios for all age groups (24-30 kg/sq m, W:H < 1, for males; and 20-26 kg/sq W:H < 1 for females) were below the lower limits of international values for obesity, where obesity is defined as BMI > 30 kg/sq or W:H > 1. This finding suggests that obesity is not a problem in adult Black Africans of Zimbabwe. Women, however, were overweight (BMI = 25-30 kg/sq m) and had larger mean waist circumferences. They were, therefore, at greater risk of health problems associated with abdominal adiposity. We suggest that clinicians, pharmacists, researchers and medical scientists should use local indices in the light of lower values observed in the present study.     

Long time follow-up of flexor tendons of the hand after reconstructive operations. Part 1. Monitoring method

OBJECTIVE: To assess whether it is possible to make accurate vertical measurements of the jaws from panoramic radiographs. METHODS: Five dry skulls were shifted 5 mm forwards and backwards and tilted 5 degrees up and down in the sagittal plane. Panoramic radiographs of each skull were obtained in nine different positions. In the maxilla, three reference lines were used and vertical measurements were made at the distal surfaces of the first premolar and first molar and in the midline. In the mandible, measurements were made at the distal surfaces of the first premolar and first molar, and at the mental foramen on both sides, and in the midline. The points and lines were marked manually and the radiographs were digitized, magnified and measured. RESULTS: Sagittal shifting and tilting had only a slight effect on measurements in the mandible. Sagittal tilting of the head had the greatest effect on all the measurements made from the line between the articular eminences to the alveolar crest, as well as measurements in the maxillary midline. CONCLUSIONS: The line between the articular eminences is unsuitable as a reference line for measurements of the tooth-bearing areas. A slight misalignment of the head does not significantly affect the vertical measurements in the mandible or of the posterior maxilla if the reference lines are in the same vertical plane as the teeth.     

Prediction of mandibular autorotation

PURPOSE: The purpose of this investigation was to test the hypothesis that the mandible rotates around the same point during maxillary impaction surgery as during initial jaw opening. This point, called the center of mandibular autorotation (CAR), could then be used to predict mandibular position and to decide whether only maxillary impaction would be needed to correct the occlusion and the facial profile. PATIENTS AND METHODS: Preoperatively, two lateral cephalograms were obtained from a consecutive series of 20 patients who underwent maxillary impaction without concomitant mandibular ramus osteotomy. One cephalogram was taken with the mandible in centric relation using a wax bite wafer and another with a jaw opening of 10 mm using a fabricated acrylic bite block with the mandible manipulated to its most retruded position. The CAR was calculated before and after jaw opening using the Rouleaux method on the lower incisor and gonion point. A third lateral cephalogram was taken within 2 days postoperatively. The postoperative lower incisal point was then transferred to the first cephalogram using cranial base superimposition. RESULTS: When the preoperative and postoperative distances between CAR and incisal point were compared, there was no significant difference between these distances, proving the hypothesis. CONCLUSIONS: The method used is a practical and precise way to determine the center of mandibular autorotation on an individual basis. The center of rotation during initial jaw opening is the same as during impaction surgery.     

The development of the septum primum relative to atrial septation in the mouse heart

The septum primum in the mouse originates as a thickened primordium with a straight rather than a sickle-shaped ventral border. It is covered on its ventral border by anterior cushion material which is continuous over the roof of the atrium with the principal anterior cushion mass. A process of cavitation thins the septum primum and precedes actual fenestration. This process shifts the membranous septum to the left thereby providing room for the septum secundum to overlap on the right side. The septum primum cannot contact the posterior cushion until closure of the sinus venosus gutter which is described. The closure of the interatrial foramen, later the foramen primum, is accomplished by cell growth of the anterior cushion material. The ventral thick border of the septum primum contributes to the ventral limbus and the caudal thickened boundary of the fossa ovalis with some contribution from the left venous valve. These boundaries as well as the membranous portion of the interatrial septum are derived from the same primordium, namely the septum primum.     

Histology of posterior scleral foramen in normal eyes: its possible role in optic nerve damage in chronic open angle glaucoma

We examined the histologic features of the posterior scleral foramen in 27 enucleated eyes (16 during autopsy and 11 with choroidal malignant melanoma). The histologic findings of the posterior scleral foramen were similar to those in previous reports. The shape of the scleral foramen was either cylindrical or truncated, the latter occurring when the inner margin of the sclera projected with a crest-like edge pressing into the optic nerve. This configuration was encountered more frequently in the upper and lower temporal aspects of the scleral foramen in 10 eyes, while the nasal rim was free of such projection in all the eyes. We hypothesize that the effect of prolonged high intraocular pressure exerted on the axonal tissue against these crest-like edges of the non-distensible scleral foramen might be the major factor in the etiology of early arcuate nerve fiber bundle defects in primary open-angle glaucoma.