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Sample records for incisor inclination positional

  1. Changes in anteroposterior position and inclination of the maxillary incisors after surgical-orthodontic treatment of skeletal class III malocclusions.

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    Zou, Bingshuang; Zhou, Yang; Lowe, Alan A; Li, Huiqi; Pliska, Benjamin

    2015-12-01

    The purpose of this study was to evaluate and compare the anteroposterior (AP) position and inclination of the maxillary incisors in subjects with class I normal occlusion and a harmonious profile with patients with skeletal class III malocclusions, and to investigate the changes in maxillary incisor inclination and AP position after surgical-orthodontic treatment in class III patients. Sixty-five subjects (35 female and 30 male; mean age: 21.8 ± 3.89 years) with normal profiles and class I skeletal and dental patterns were selected as a control sample. Sixty-seven patients (38 female and 29 male; mean age: 21.3 ± 3.31 years) with skeletal and dental class III malocclusions who sought surgical-orthodontic treatment were used as the study sample. Subjects were asked to smile and profile photographs were taken with the head in a natural position and the maxillary central incisors and the forehead in full view; cephalograms were taken and superimposed on the profile pictures according to the outline of the forehead and nose. Forehead inclination, maxillary incisor facial inclination and the AP position of the maxillary central incisor relative to the forehead (FAFFA) were measured on the integrated images and statistical analyses were performed. In both groups, there were no significant male/female differences in either the maxillary central incisor inclination or AP position. Female subjects had a significantly steeper forehead inclination compared with males (P 0.05). In the control group, 84.6% had the facial axial point (FA) of their maxillary central incisors positioned between lines through the forehead facial axis (FFA) point and the glabella. In the study group, however, 79.1% had the maxillary central incisors positioned posterior to the line through the FFA point and the difference with the control group was statistically significant (P 0.05). With the integrated radiograph-photograph method, the lateral cephalogram was reoriented, which makes it possible

  2. Lower incisor inclination regarding different reference planes.

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    Zataráin, Brenda; Avila, Josué; Moyaho, Angeles; Carrasco, Rosendo; Velasco, Carmen

    2016-09-01

    The purpose of this study was to assess the degree of lower incisor inclination with respect to different reference planes. It was an observational, analytical, longitudinal, prospective study conducted on 100 lateral cephalograms which were corrected according to the photograph in natural head position in order to draw the true vertical plane (TVP). The incisor mandibular plane angle (IMPA) was compensated to eliminate the variation of the mandibular plane growth type with the formula "FMApx.- 25 (FMA) + IMPApx. = compensated IMPA (IMPACOM)". As the data followed normal distribution determined by the KolmogorovSmirnov test, parametric tests were used for the statistical analysis, Ttest, ANOVA and Pearson coefficient correlation test. Statistical analysis was performed using a statistical significance of p planes. There were statistically significant differences among the means of the planes measured, except for IMPACOM, FMIA and TVP. The IMPA differed significantly from the IMPACOM. The compensated IMPA and the FMIA did not differ significantly from the TVP. The true horizontal plane was mismatched with Frankfort plane in 84% of the sample with a range of 19°. The true vertical plane is adequate for measuring lower incisor inclination. Sociedad Argentina de Investigación Odontológica.

  3. Aesthetic evaluation of profile incisor inclination.

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    Ghaleb, Nathalie; Bouserhal, Joseph; Bassil-Nassif, Nayla

    2011-06-01

    The objectives of this study were to evaluate (1) the impact of maxillary incisor inclination on the aesthetics of the profile view of a smile, (2) to determine the most aesthetic inclination in the profile view of a smile and correlate it with facial features, and (3) to determine if dentists, orthodontists, and laypeople appreciate differently incisor inclination in smile aesthetics. A smiling profile photograph of a female subject (22 years of age) who fulfilled the criteria of soft tissue normative values and a balanced smile was obtained. The photograph was manipulated to simulate six lingual and labial inclinations at 5 degree increments to a maximum of 15 degrees. The seven photographs were randomly distributed in a binder to three groups of raters (30 dentists, 30 orthodontists, and 30 laypeople) who scored the attractiveness of the photographic variations using a visual analogue scale. Comparison of the mean scores was carried out by repeated analysis of variance, univariate tests, and multiple Bonferroni comparisons. The results showed a statistically significant interaction between the rater's profession and the aesthetic preference of incisor inclination (P = 0.013). The profile smile corresponding to an increase of 5 degrees in a labial direction had the highest score among all professions and among male and female raters. Orthodontists preferred labial crown torque; dentists and laypeople did not appreciate excessive incisor inclination in either the lingual or the labial directions. The most preferred smile matched with a maxillary incisor inclined 93 degrees to the horizontal line and +7 degrees to the lower facial third.

  4. Comparison of the effect of labiolingual inclination and anteroposterior position of maxillary incisors on esthetic profile in three different facial patterns

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    Chirivella, Praveen; Singaraju, Gowri Sankar; Mandava, Prasad; Reddy, V Karunakar; Neravati, Jeevan Kumar; George, Suja Ani

    2017-01-01

    Objective: To test the null hypothesis that there is no effect of esthetic perception of smiling profile in three different facial types by a change in the maxillary incisor inclination and position. Materials and Methods: A smiling profile photograph with Class I skeletal and dental pattern, normal profile were taken in each of the three facial types dolichofacial, mesofacial, and brachyfacial. Based on the original digital image, 15 smiling profiles in each of the facial types were created using the FACAD software by altering the labiolingual inclination and anteroposterior position of the maxillary incisors. These photographs were rated on a visual analog scale by three panels of examiners consisting of orthodontists, dentists, and nonprofessionals with twenty members in each group. The responses were assessed by analysis of variance (ANOVA) test followed by post hoc Scheffe. Results: Significant differences (P esthetics. The result of the ANOVA showed differences among the three groups for certain facial profiles. Conclusion: The hypothesis was rejected. The esthetic perception of labiolingual inclination and anteroposterior of maxillary incisors differ in different facial types, and this may effect in formulating treatment plans for different facial types. PMID:28197396

  5. Effect of incisor inclination changes on cephalometric points a and b

    International Nuclear Information System (INIS)

    Hassan, S.; Shaikh, A.; Fida, M.

    2015-01-01

    The position of cephalometric points A and B are liable to be affected by alveolar remodelling caused by orthodontic tooth movement during incisor retraction. This study was conducted to evaluate the change in positions of cephalometric points A and B in sagittal and vertical dimensions due to change in incisor inclinations. Methods: Total sample of 31 subjects were recruited into the study. The inclusion criteria were extraction of premolars in upper and lower arches, completion of growth and orthodontic treatment. The exclusion criteria were patients with craniofacial anomalies and history of orthodontic treatment. By superimposition of pre and post treatment tracings, various linear and angular parameters were measured. Various tests and multiple linear regression analysis were performed to determine changes in outcome variables. Statistically significant p-value was <0.05. Results:One-sample t-test showed that change in position of only point A was statistically significant which was 1.61mm (p<0.01) in sagittal direction and 1.49mm (p<0.01) in vertical direction. Multiple linear regression analysis showed that if we retrocline upper incisor by 100, the point A will move superiorly by 0.6mm. Conclusions: Total change in the position of point A is in a downward and forward direction. Total Change in upper incisors inclinations causes change in position of point A only in vertical direction. (author)

  6. Comparison of incisor inclination in patients with Class III malocclusion treated with orthognathic surgery or orthodontic camouflage.

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    Troy, Beth A; Shanker, Shiva; Fields, Henry W; Vig, Katherine; Johnston, William

    2009-02-01

    Reports comparing Class III patients treated by camouflage and those treated by orthognathic surgery are not numerous. The purpose of this study was to compare the dental and skeletal values of Class III patients treated with these methods against normative data and over the course of treatment. Thirty-three surgical and 39 camouflage Class III patients were selected from a graduate orthodontic clinic and regional private practices, and lateral cephalograms were digitized. Skeletal and dental values were obtained, and mean and efficacy evaluations referenced to ethnic norms were calculated. At pretreatment, the surgery patients had more severe skeletal discrepancies and more compensated incisors. During presurgical orthodontic treatment, most of the surgery group's mandibular incisors were significantly decompensated, although half of the maxillary incisors remained compensated. The surgical move improved 90% of these patients but to only 60% to 65% of the norm. The camouflage group was compensated at pretreatment, and they became more compensated in the end. After treatment, there were no differences between the incisor positions of the 2 groups. There was no statistical difference in incisor inclination and position between the Class III surgical and camouflage groups after treatment; there was a significant difference in the pretreatment and posttreatment incisor inclination and position compared with normative values for both the surgical and the camouflage groups; the maxillary and mandibular incisors were not adequately decompensated in the surgical group, but significant improvement in mandibular incisor position and axial inclination was achieved presurgically. The outcome of the surgical correction was limited by the inadequate presurgical orthodontic incisor decompensation, and orthodontic compensation of incisors occurred postsurgically to achieve an optimal occlusal result.

  7. Coordinating bracket torque and incisor inclination : Part 3: Validity of bracket torque values in achieving norm inclinations.

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    Zimmer, Bernd; Sino, Hiba

    2018-03-19

    To analyze common values of bracket torque (Andrews, Roth, MBT, Ricketts) for their validity in achieving incisor inclinations that are considered normal by different cephalometric standards. Using the equations developed in part 1 (eU1 (BOP) = 90° - BT (U1) - TCA (U1) + α 1 - α 2 and eL1 (BOP) = 90° - BT (L1) - TCA (L1) + β 1 - β 2 ) (abbreviations see part 1) and the mean values (± SD) obtained as statistical measures in parts 1 and 2 of the study (α 1 and β 1 [1.7° ± 0.7°], α 2 [3.6° ± 0.3°], β 2 [3.2° ± 0.4°], TCA (U1) [24.6° ± 3.6°] and TCA (L1) [22.9° ± 4.3°]) expected (= theoretically anticipated) values were calculated for upper and lower incisors (U1 and L1) and compared to targeted (= cephalometric norm) values. For U1, there was no overlapping between the ranges of expected and targeted values, as the lowest targeted value of (58.3°; Ricketts) was higher than the highest expected value (56.5°; Andrews) relative to the bisected occlusal plane (BOP). Thus all of these torque systems will aim for flatter inclinations than prescribed by any of the norm values. Depending on target values, the various bracket systems fell short by 1.8-5.5° (Andrews), 6.8-10.5° (Roth), 11.8-15.5° (MBT), or 16.8-20.5° (Ricketts). For L1, there was good agreement of the MBT system with the Ricketts and Björk target values (Δ0.1° and Δ-0.8°, respectively), and both the Roth and Ricketts systems came close to the Bergen target value (both Δ2.3°). Depending on target values, the ranges of deviation for L1 were 6.3-13.2° for Andrews (Class II prescription), 2.3°-9.2° for Roth, -3.7 to -3.2° for MBT, and 2.3-9.2° for Ricketts. Common values of upper incisor bracket torque do not have acceptable validity in achieving normal incisor inclinations. A careful selection of lower bracket torque may provide satisfactory matching with some of the targeted norm values.

  8. Relationship between the position of upper and lower incisors and the internal structure of symphysis

    International Nuclear Information System (INIS)

    Suzuki, Kayou; Nishide, Masashi; Ishii, Yasumasa; Enomoto, Yutaka; Kawamura, Akira; Kasai, Kazutaka

    2002-01-01

    The aim of this study was to investigate the relationship between the position of the upper and lower incisors and cortical bone thickness and CT value of mandibular symphysis obtained by CT images and cephalograms. The specimens were 24 dry skulls of mordern Japanese males (mean age 29 years) without marked crowding and missing tooth, which had been preserved in the Tokyou University Museum. The data were transferred to a workstation, and CT value and thickness of cortical bone were measured. The dentofacial morphology was investigated with a lateral cephalogram. The results were as follows; The thickness of cortal bone was more thicker in order of basal, lingual and labial cortical bone. The CT value showed the same tendency as cortical bone thickness. Significant correlation coefficients were found between cortical bone thickness and CT value in 30, 60, 90, 120 degree areas. The inclination of upper incisors was negatively related to the CT value in basal and lingual region of symphysis. The inclination of lower incisors was positively related to the CT value in basal and lingual region of symphysis. The interincisor angle was positively related to the CT value in basal region of symphysis. In conclusion, the results of this study suggested that the labio-lingual inclination of the upper and lower incisors was associated with the CT value of basal region of sysphysis. It is suggested that the internal structures of symphysis which relate to the occlusion types of incisors are affected by function of masticatory muscles. (author)

  9. Analysis of the root position of the maxillary incisors in the alveolar bone using cone-beam computed tomography

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    Jung, Yun Hoa; Cho, Bong Hee [Dept. of Oral and Maxillofacial Radiology, School of Dentistry, Pusan National University, Yangsan (Korea, Republic of); Hwang, Jae Jun [Dept. of Oral and Maxillofacial Radiology, Yonsei University College of Dentistry, Seoul (Korea, Republic of)

    2017-09-15

    The purpose of this study was to measure the buccal bone thickness and angulation of the maxillary incisors and to analyze the correlation between these parameters and the root position in the alveolar bone using cone-beam computed tomography (CBCT). CBCT images of 398 maxillary central and lateral incisors from 199 patients were retrospectively reviewed. The root position in the alveolar bone was classified as buccal, middle, or palatal, and the buccal type was further classified into subtypes I, II, and III. In addition, the buccolingual inclination of the tooth and buccal bone thickness were evaluated. A majority of the maxillary incisors were positioned more buccally within the alveolar bone, and only 2 lateral incisors (0.5%) were positioned more palatally. The angulation of buccal subtype III was the greatest and that of the middle type was the lowest. Most of the maxillary incisors exhibited a thin facial bone wall, and the lateral incisors had a significantly thinner buccal bone than the central incisors. The buccal bone of buccal subtypes II and III was significantly thinner than that of buccal subtype I. A majority of the maxillary incisor roots were positioned close to the buccal cortical plate and had a thin buccal bone wall. Significant relationships were observed between the root position in the alveolar bone, the angulation of the tooth in the alveolar bone, and buccal bone thickness. CBCT analyses of the buccal bone and sagittal root position are recommended for the selection of the appropriate treatment approach.

  10. Preplanning contemporary incisor positioning using inclinometer: A clinical and cephalometric study

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    Saurabh Birla

    2014-01-01

    Conclusion: Third-order measurements using inclinometer device can offer a simple way to get an objective and rapid vision of the incisors inclination and might be a helpful guideline to the choice of low or high torque brackets. Incisor inclination is strongly correlated with skeletal-sagittal data, but little with skeletal-vertical findings.

  11. Control of lower incisor inclination with a completely customized lingual appliance for dentoalveolar compensation of class III malocclusion.

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    Lossdörfer, Stefan; Schwestka-Polly, Rainer; Wiechmann, Dirk

    2013-09-01

    Bracket slots and orthodontic archwires offering high dimensional precision are needed for fully customized lingual appliances. We aimed to investigate whether high-precision appliances of this type enable dentoalveolar compensation of class III malocclusion so that lower incisor inclination at the end of treatment will closely match the anticipated situation as defined in a pretreatment setup. This retrospective study included a total of 34 consecutive patients who had worn a fully customized lingual appliance to achieve dentoalveolar compensation for class III malocclusion by intermaxillary elastics, or proximal enamel reduction, or extraction of teeth in one or both jaws. Casts fabricated at different points in time were three-dimensionally scanned to analyze how precisely the lower incisor inclinations envisioned in the setup were implemented in clinical practice. Aside from minor deviations of ±3.75°, the lower incisor inclinations were clinically implemented as planned even in patients with major sagittal discrepancies. Treatment goals predefined in a setup of dentoalveolar compensation for class III malocclusion can be very precisely achieved via a customized lingual appliance. Correct planning can prevent undesirable lingual tipping of the lower incisors. This finding should not encourage a more liberal use of dentoalveolar compensation, but it should heighten clinicians' awareness of how essential it is to sufficiently consider the individual anatomy of the dentoalveolar complex during treatment planning.

  12. Evaluation of the lower incisor inclination during alignment and leveling using superelastic NiTi archwires: a laboratory study

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    Carolina Baratieri

    2012-06-01

    Full Text Available OBJECTIVE: The aim of this laboratory study is to evaluate the influence of the shape and the length limitation of superelastic nickel-titanium (NiTi archwires on lower incisors inclination during alignment and leveling. METHODS: Metal teeth mounted on a typodont articulator device were used to simulate a malocclusion of the mandibular arch (-3.5 mm model discrepancy. Three different shapes (Standard, Accuform and Ideal of superelastic NiTi archwires (Sentalloy, GAC, USA were tested. Specimens were divided in two groups: Group I, with no limitation of the archwire length; and Group II, with distal limitation. Each group had thirty specimens divided into three subgroups differentiated by the archwire shape. All groups used round wires with diameters of 0.014-in, 0.016-in, 0.018-in and 0.020-in. The recording of all intervals was accomplished using standardized digital photographs with orthogonal norm in relation to median sagittal plane. The buccolingual inclination of the incisor was registered using photographs and software CorelDraw. RESULTS: The results were obtained using ANOVA and Tukey's test at a significant level of 5%. The inclination of the lower incisor increased in both groups and subgroups. The shape of the archwire had statistically significant influence only in Group I - Standard (11.76º, Ideal (5.88º and Accuform (1.93º. Analyzing the influence of the length limitation, despite the mean incisor tipping in Group II (3.91º had been smaller than Group I (6.52º, no statistically significant difference was found, except for Standard, 3.89º with limitation and 11.76º without limitation. The greatest incisor tipping occurred with the 0.014-in archwires.

  13. Coordinating bracket torque and incisor inclination : Part 2: Reproducibility and statistical measures of the torque coordination angle (TCA).

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    Sino, H; Zimmer, B; Schelper, I; Schenk-Kazan, S; Streibelt, F

    2018-03-09

    To determine the reproducibility and statistical measures of the torque coordination angle (TCA). A total of 107 final cephalograms and corresponding casts were included, all reflecting treatment outcomes that met high qualitative standards, one of them being a Peer Assessment Rating (PAR) score of ≤3. Based on these records, the TCA was measured as a parameter to identify differences related to tooth morphology and bracket position between the torque-relevant reference plane at the bracket base and the long axis of a tooth. All measurements were performed on upper and lower central incisors (U1 and L1). Several reproducibility assessments for the TCA measurements yielded good results, including objectivity at 1.26 ± 0.81° (U1) or 1.41 ± 1.18° (L1), examiner reliability at 1.30 ± 0.97° (U1) or 1.25 ± 0.82° (L1), and method reliability at 1.80 ± 1.13° (U1) or 1.53 ± 1.07° (L1). The statistical measures revealed a high degree of interindividual variability. With bracket placement 4.5 mm (U1) or 4.0 mm (L1) above the incisal edge, the differences between the maximum and minimum TCA values were similarly large in both jaws (21.0° for U1 or 20.0° for L1), given mean TCA values of 24.6 ± 3.6° (U1) or 22.9 ± 4.3° (L1). Moving the bracket placement from 3.5 to 5.5 mm (U1) or from 3.0 to 5.0 mm (L1) changed the mean TCA values by 4.5° (U1) or 3.2° (L1). The TCA is a suitable cephalometric parameter to identify differences related to tooth morphology and bracket placement. Given its high interindividual variability, the fixed torque value of a specific bracket system should not be expected to produce the same incisor inclinations across patients.

  14. Exploration of variations in positions of upper and lower incisors, overjet, overbite, and irregularity index in orthodontic patients with dissimilar depths of curve of spee

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    Kumari, N.; Fida, M.; Shaikh, A.

    2017-01-01

    The position and arrangement of teeth as well as the entire scheme of occlusion differs from one individual to the other .The purpose of this study was to examine differences in position and inclination of incisors, overjet, overbite and lower arch crowding in subjects with different depths of curve of Spee and to determine correlations between depth of curve of Spee and these variables. Methods: The sample comprised of 114 patients (55 females and 59 males) with fully erupted permanent second molars (age 12-25 years), having no history of previous orthodontic treatment, no craniofacial anomalies, and no missing permanent teeth. Study parameters were assessed by using pretreatment lateral cephalograms and dental casts of orthodontic patients. The entire sample was divided into three groups according to depth of curve of Spee (mild Spee=38, moderate Spee=38, severe Spee=38). Descriptive statistics were calculated. Differences between the Spee groups were assessed by analysis of variance. In addition, correlation coefficients were calculated between curve of Spee and other parameters. Results: Statistically significant differences were found in upper incisor inclination (p=0.000), lower incisor inclination (p=0.003), Steiner's mandibular plane angle (p=0.000), overjet (p=0.001), overbite (p=0.000) and irregularity index (p=0.008) among the Spee groups. Moreover, statistically significant positive correlations were found between curve of Spee and overjet, overbite and irregularity index. Upper and lower incisor inclinations as well as mandibular plane angle were found to have statistically significant but negative correlations with curve of Spee. Conclusion: Overjet and overbite in severe Spee group are larger than in mild and moderate Spee groups. There is negative correlation between curve of Spee depth and inclinations of upper and lower incisors. There is positive correlation between curve of Spee depth and severity of lower anterior crowding and Steiner

  15. Do different vertical positions of maxillary central incisors influence smile esthetics perception?

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    Menezes, Erica Bretas Cabral; Bittencourt, Marcos Alan Vieira; Machado, Andre Wilson

    2017-01-01

    The purpose of this study was to determine the perception of smile esthetics among orthodontists and layperson, with respect to different maxillary central incisors vertical positions in full-face and close-up smile analyses. Frontal photographs of the smiles of two adult women were used. Images were altered to create a symmetrical image with the gingival margin levels of the maxillary canines matching the central incisors and a 1.0-mm central-to-lateral incisal step. Later, the images were altered in order to create six different central incisor vertical positions in 0.5-mm increments. The images were randomly assembled in an album, which was given to 114 judges, 57 orthodontists and 57 laypersons, who were asked to evaluate the attractiveness of the images using the visual analog scale. The data collected were statistically analyzed by means of 1-way analysis of variance with the Tukey post-hoc test and the Student t test. The highest rated smiles showed two notable characteristics: a) the central incisor gingival margins matched or were 0.5 mm below the line of the canine gingival margins and; b) the central-to-lateral incisal step was 1.0 to 1.5 mm. The worst smiles showed two notable characteristics: a) the central incisor gingival margins were 1.0 mm above or 1.5 mm below the canine gingival margins and; b) no step between the centrals and laterals or a 2.5-mm step. The vertical position of the maxillary central incisors significantly affected the perception of the smile esthetics, whereas slightly extruded central incisors were more esthetically preferred than intruded.

  16. Do different vertical positions of maxillary central incisors influence smile esthetics perception?

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    Erica Bretas Cabral Menezes

    Full Text Available ABSTRACT INTRODUCTION: The purpose of this study was to determine the perception of smile esthetics among orthodontists and layperson, with respect to different maxillary central incisors vertical positions in full-face and close-up smile analyses. METHODS: Frontal photographs of the smiles of two adult women were used. Images were altered to create a symmetrical image with the gingival margin levels of the maxillary canines matching the central incisors and a 1.0-mm central-to-lateral incisal step. Later, the images were altered in order to create six different central incisor vertical positions in 0.5-mm increments. The images were randomly assembled in an album, which was given to 114 judges, 57 orthodontists and 57 laypersons, who were asked to evaluate the attractiveness of the images using the visual analog scale. The data collected were statistically analyzed by means of 1-way analysis of variance with the Tukey post-hoc test and the Student t test. RESULTS: The highest rated smiles showed two notable characteristics: a the central incisor gingival margins matched or were 0.5 mm below the line of the canine gingival margins and; b the central-to-lateral incisal step was 1.0 to 1.5 mm. The worst smiles showed two notable characteristics: a the central incisor gingival margins were 1.0 mm above or 1.5 mm below the canine gingival margins and; b no step between the centrals and laterals or a 2.5-mm step. CONCLUSION: The vertical position of the maxillary central incisors significantly affected the perception of the smile esthetics, whereas slightly extruded central incisors were more esthetically preferred than intruded.

  17. Improving wellbore position accuracy of horizontal wells by using a continuous inclination measurement from a near bit inclination MWD sensor

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    Berger, P. E.; Sele, R. [Baker Hughes INTEQ (United States)

    1998-12-31

    Wellbore position calculations are typically performed by measuring azimuth and inclination at 10 to 30 meter intervals and using interpolation techniques to determine the borehole position between survey stations. The input parameters are measured depth (MD), azimuth and inclination, where the two parameters are measured with an MWD tool. Output parameters are the geometric coordinates; true value depth (TVD), north and east. By improving the accuracy of the inclination measurement reduces the uncertainty of the calculated TVD value, resulting in increased confidence in wellbore position. Significant improvements in quality control can be achieved by using multiple sensors. This paper describes a set of quality control parameters that can be used to verify individual sensor performance and a method for calculating TVD uncertainty in horizontal wells, using a single sensor or a combination of sensors. 6 refs., 5 figs.

  18. Lateral incisor root resorption and active orthodontic treatment in the early mixed dentition.

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    Amlani, M S; Inocencio, F; Hatibovic-Kofman, S

    2007-12-01

    To evaluate the presence of root resorption in the lateral incisor after active orthodontic treatment in the early mixed dentition. Twenty-six children treated at the Children's Clinic of the Schulich School of Medicine and Dentistry at the University of Western Ontario were examined radiographically for lateral incisors root resorption before and after early active treatment to align upper incisors (2 x 4 appliance). In addition, canine inclinations to the midline and to the long axis of the lateral incisor as well as the most medial position of the canine crown were measured as potential risk factors for root resorption. 8% (4) of the lateral incisors exhibited root resorption and the mean crown-to-root ratio of these teeth was significantly higher than that for lateral incisors not exhibiting root resorption. Similarly, mean canine inclinations to the midline and to the long axis of the lateral incisor were also significantly higher for the root resorption group. No association could be found between the most medial position of the canine crown and root resorption in the lateral incisor. This study showed that active orthodontic treatment in the early mixed dentition does not increase the risk for root resorption in the lateral incisors as long as the clinician takes into consideration canine inclinations and their potential effect on root resorption. Limitations inherent to radiographic assessment are acknowledged.

  19. Position and stability of the mandibular incisors after rapid maxillary expansion

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    Darcy Flávio Nouer

    Full Text Available Objective: To make a cephalometric evaluation of the position and stability of the mandibular incisors immediately after rapid maxillaryexpansion and after a containment period of five months. Methods: The sample consisted of 21 schoolchildren, aged between 6 years and 11 months and 11 years, with mixed dentition, posterior reverse articulation (posterior cross bite, and erupted permanent first molars. The children were randomly divided into two groups: Group1 (composed of eleven children, in whom the encapsulated rapid maxilla expander was used, and Group 2 (composed of ten children, inwhom the conventional Hyrax expander was used. Three lateral teleradiographs of each individual were taken: before treatment, after rapid maxillary expansion, and after a containment period of five months. The cephalometric measurements used for analyzing the incisors were: /1.NB, /1-NB, /1-Line I, IMPA and /1-Jr. The data were submitted to the Dalhberg test, to calculate the error of repeatability, and to ANOVA (p<0.05. Results: The result showed significant difference between the adopted mechanics, but showed no difference between the initial measures, those after rapid expansion of the maxilla and final measures for all the distances, except for /1-Jr. Conclusion: Rapid maxillary expansion, using the encapsulated appliance or Hyrax, caused no significant alteration in the distances: /1.NB, /1-NB, /1-Line I, IMPA; before, after rapid maxillary expansion and after containment.

  20. Influence of the vertical position of maxillary central incisors on the perception of smile esthetics among orthodontists and laypersons.

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    Machado, Andre Wilson; McComb, Ryan W; Moon, Won; Gandini, Luiz Gonzaga

    2013-12-01

    The purpose of this study was to determine the perception of smile esthetics among orthodontists and laypeople with respect to different upper central incisor vertical positions in a frontal smile analysis. A frontal close-up smile photo of an adult Caucasian woman was selected. The patient had healthy upper anterior dentition and had no history of orthodontic treatment. Images were altered in order to create six different central incisor vertical positions in 0.5-mm increments. All images were assessed in three different views: full smile, gingival close-up excluding incisal edges, and incisal close-up excluding gingival margins. Images were randomly assembled in an album, which was given to 120 judges: 60 orthodontists and 60 laypersons. Each rater was asked to evaluate the attractiveness of the images using the visual analog scale. The data collected were then statistically analyzed. The highest rated smiles showed two notable characteristics: the central-to-lateral incisal step was 1.5 mm; and the central incisor gingival margins matched the laterals, and both were 0.5 mm below the line of the canine gingival margins. The least attractive smile was the one with no step between the centrals and laterals, and with the central incisor gingival margins 1.0 mm above the canine gingival margins. The results of this study indicate that slightly extruded upper central incisors are more esthetically preferred than intruded. The upper central incisors are the key determinant in evaluating smile esthetics, and thus, the assessment of their ideal vertical positioning is an aspect of paramount importance. © 2013 Wiley Periodicals, Inc.

  1. Positional changes of maxillary central incisors following orthodontic treatment using single-crown implants as fixed reference markers

    DEFF Research Database (Denmark)

    Brahem Ben, Elissa; Holm, Bente; Sonnesen, L

    2017-01-01

    OBJECTIVES: This follow-up study (1) compares tooth displacement of central incisors in patients with and without pre-implant orthodontic treatment and (2) investigates whether sex, age, or orthodontic retention have an effect on tooth displacement after the insertion of single-crown implants...... during baseline examinations after prosthetic rehabilitation and at the final follow-up examination at least 5 years later. A total of 114 dental casts were digitalized and aligned using a software program to measure changes in the positions of the central incisors. RESULTS: After a follow-up period......, and there were no significant correlations with patient age or sex. CONCLUSION: The majority of patients had minor vertical (60%) or horizontal (67%) tooth displacement of the central incisors (0.25-0.75 mm) after a minimum follow-up period of 5 years. This study found no significant differences in tooth...

  2. A CAD-CAM prosthodontic option and gingival zenith position for a rotated maxillary right central incisor: An evaluation

    Directory of Open Access Journals (Sweden)

    Mukesh Singhal

    2012-01-01

    Conclusion: Digital imaging provides an immediate treatment option for the patients. Software also provides an interim aid, for the clinician as well as technician, in the form of two-dimensional photographs. CAD-CAM is entirely a helping instrument against the conservative prosthetic options and gingival zenith position for a rotated central incisor. It helps in patient education and in motivation.

  3. Influence of Preadjusted Bracket Shape and Positioning Reference on Angulation of Upper Central Incisor.

    Science.gov (United States)

    Topolski, Francielle; de O Accorsi, Mauricio A; Trevisi, Hugo J; Cuoghi, Osmar A; Moresca, Ricardo

    2016-10-01

    To verify the influence of different bracket shapes and placement references according to Andrews and MBT systems on the expression of angulation in upper central incisors (UCI). Bracket positioning and mesiodistal dental movement simulations were performed and the angulations produced in the dental crown were evaluated, based on computed tomography scan images of 30 UCI and AutoCAD software analysis. Rectangular (Andrews) and rhomboid (MBT) brackets were placed according to the references recommended by Andrews and MBT systems - long axis of the clinical crown (LACC) and incisal edge (IE) respectively. Data showed that the use of LACC as reference for bracket positioning produced 5° and 4° UCI angulations in Andrews and MBT brackets respectively. The use of IE produced a 1.2° mean angulation in UCI for both brackets. When the LACC was used as reference for bracket positioning, the UCI crown angulation corresponded to the angulation built into the brackets, regardless of shape, while the use of IE resulted in natural crown angulation, regardless of bracket shape. This research contributes to guide the orthodontist in relation to the different treatment techniques based on the use of preadjusted brackets.

  4. [Comparison of clinical effects of Co-Cr alloy cast post-core and everStick fiber post in restoration of labially or lingually inclined maxillary central incisor].

    Science.gov (United States)

    Qian, Yu-Mei; Zhong, Qun; Chen, Shuang

    2017-02-01

    To compare the clinical effect of Co-Cr alloy cast post-core and everStick fiber post in restoration of maxillary central incisor with labial or lingual inclination, and provide theoretical basis for clinical application. Ninety-seven labially or lingually inclined maxillary central incisors were treated in our hospital from March 2012 to March 2014. The patients were randomly divided into group A (n=49) and group B (n=48), and received post -core and crown restoration. Patients in group A underwent Co-Cr alloy cast post and core restoration and patients in group B underwent everStick fiber post and core restoration. After two-year of follow-up, root fracture, post break, crown or post dislodgment and gingival marginal discoloration were recorded and analyzed using SPSS 19.0 software package. Chi-square test showed that the success rate of restoration was significantly different between 2 groups (P<0.05). The incidence of root fracture and gingival marginal discoloration of Co-Cr alloy cast post-core was higher than that of everStick fiber post, but there was no significant difference in the incidence of post break, crown or post dislodgment. EverStick fiber post is better than Co-Cr alloy cast post and core to prevent root fracture and gingival marginal discoloration. Its fracture pattern is repairable and favorable for preserving tooth.

  5. Affect and craving: positive and negative affect are differentially associated with approach and avoidance inclinations.

    Science.gov (United States)

    Schlauch, Robert C; Gwynn-Shapiro, Daniel; Stasiewicz, Paul R; Molnar, Danielle S; Lang, Alan R

    2013-04-01

    Research on reactivity to alcohol and drug cues has either ignored affective state altogether or has focused rather narrowly on the role of negative affect in craving. Moreover, until recently, the relevant analyses of affect and craving have rarely addressed the ambivalence often associated with craving itself. The current study investigated how both negative and positive affect moderate approach and avoidance inclinations associated with cue-elicited craving in a clinical sample diagnosed with substance use disorders. One hundred forty-four patients (age range of 18-65, mean 42.0; n=92 males) were recruited from an inpatient detoxification unit for substance abuse. Participants completed a baseline assessment of both positive and negative affect prior to completing a cue-reactivity paradigm for which they provided self-report ratings of inclinations to approach (use) and avoid (not use) alcohol, cigarettes, and non-psychoactive control substances (food and beverages). Participants with elevated negative affect reported significantly higher approach ratings for cigarette and alcohol cues, whereas those high in positive affect showed significantly higher levels of avoidance inclinations for both alcohol and cigarette cues and also significantly lower approach ratings for alcohol cues, all relative to control cues. Results for negative affect are consistent with previous cue reactivity research, whereas results for positive affect are unique and call attention to its clinical potential for attenuating approach inclinations to substance use cues. Further, positive affect was related to both approach and avoidance inclinations, underscoring the utility of a multidimensional conceptualization of craving in the analysis. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Autotransplantation of a Strange Positioned Impacted Central Incisor in a surgically Prepared Socket: A Miracle Esthetic Concept.

    Science.gov (United States)

    Jaiswara, Chandresh; Srivastava, Vinay K; Dhiman, Neeraj

    2016-01-01

    Esthetics is a prime concern for a young lady. Any anomaly in the anterior tooth may create anxiety and depression. This anxiety and depression may hamper her married life and overall personality. This case report reveals an unerupted right central incisor situated in a strange position, creating space in the maxillary anterior region and giving an unesthetic appearance. Autotransplantation is a method of choice for a strangely positioned impacted central incisor in a new appropriate site. This method offers a new treatment option for some clinical situations if orthodontic approach is not possible. It permits tooth movement to a distant or the opposite side of the same dental arch as well as to the opposite jaw. This procedure also offers potential benefits of reestablishment of normal alveolar process development, esthetics, functions, and arch integrity. This procedure has the potential to become a viable alternative treatment plan for young patients of low socioeconomic status, allowing the reestablish-ment and restoration of a missing tooth and their functions. This article discusses methods of auto-reimplantation of a tooth in a fresh surgically prepared socket, its biological principle, and establishment of functions, esthetics, and phonetics. Jaiswara C, Srivastava VK, Dhiman N. Autotransplantation of a Strange Positioned Impacted Central Incisor in a surgically Prepared Socket: A Miracle Esthetic Concept. Int J Clin Pediatr Dent 2016;9(3):269-272.

  7. Positional changes of maxillary central incisors following orthodontic treatment using single-crown implants as fixed reference markers.

    Science.gov (United States)

    Brahem, E B; Holm, B; Sonnesen, L; Worsaae, N; Gotfredsen, K

    2017-12-01

    This follow-up study (1) compares tooth displacement of central incisors in patients with and without pre-implant orthodontic treatment and (2) investigates whether sex, age, or orthodontic retention have an effect on tooth displacement after the insertion of single-crown implants. Fifty-seven patients - thirty-seven with (test group) and twenty without pre-implant orthodontic treatment (control group) - were rehabilitated with 89 single-crown implants in the upper maxilla. Clinical and radiographic data, clinical photographs, and dental casts were collected during baseline examinations after prosthetic rehabilitation and at the final follow-up examination at least 5 years later. A total of 114 dental casts were digitalized and aligned using a software program to measure changes in the positions of the central incisors. After a follow-up period of at least five years, 87% of the central incisors measured in the test group were displaced >0.25 mm vertically compared with 70% in the control group. Seventy-eight percent of the test group teeth had moved >0.25 mm horizontally compared with 55% in the control group. These differences were not significant, and there were no significant correlations with patient age or sex. The majority of patients had minor vertical (60%) or horizontal (67%) tooth displacement of the central incisors (0.25-0.75 mm) after a minimum follow-up period of 5 years. This study found no significant differences in tooth displacement comparing patients with and without pre-implant orthodontic treatment. No significant effect of sex, age, orthodontic retention, or implant location was observed on tooth displacement. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  8. Position and Eruption of Permanent Maxillary Canines in Cases of Maxillary Lateral Incisor Agenesis in Mixed Dentition.

    Science.gov (United States)

    Lamas, Cátia; Lavall, Asela; Pinho, Teresa

    2018-01-01

    Assess whether the permanent maxillary canine (MC) has a natural tendency to erupt mesially in children with maxillary lateral incisors agenesis (MLIA), compared to children without agenesis. This retrospective, observational, cross-sectional study consisted of children between 5 and 12 years old divided into three groups: the first group with unilateral MLIA, in which an intraindividual analysis was performed, the second group presented bilateral MLIA, and the third group with patients without agenesis. These last two groups were matched for comparison interindividual, being pared by sex and maturation of the MC. The canine position in the horizontal sector showed a clear mesial positioning of the MC on the agenesis side in individuals with unilateral MLIA (group 1) when compared with the counter lateral side; and in individuals with bilateral MLIA (Group 2) compared with control Individuals without agenesis (group 3). Even with the maintenance of this deciduous tooth in the dental arch, the MC keeps its tendency to mesial eruption. There is a greater tendency for mesial angulation of the maxillary canine in patients with MLIA, regardless of the presence or absence of deciduous lateral incisor.

  9. Apical root resorption of incisors after orthodontic treatment of impacted maxillary canines: a radiographic study.

    Science.gov (United States)

    Brusveen, Elin Marie Gravdal; Brudvik, Pongsri; Bøe, Olav Egil; Mavragani, Maria

    2012-04-01

    The purpose of the study was to evaluate impacted maxillary canines as risk factor for orthodontic apical root resorption. The sample comprised 66 patients treated with fixed appliances. Thirty-two patients with a unilateral impacted maxillary canine, which was distanced from the roots of the incisors at a preliminary phase of treatment before bonding, formed the impaction group, and 34 patients without impactions served as the controls. Root shortening was calculated by using pretreatment and posttreatment intraoral radiographs. Inclination of the eruption path of the impacted canine relative to the midline, axis of the lateral incisor, and nasal line, root development, and the medial and vertical positions of the impacted tooth were recorded on orthopantomograms and lateral cephalometric films. The follicle/tooth ratio was evaluated by using periapical radiographs. No significant difference in apical resorption of the maxillary incisors was detected between the impaction and control groups, or between the incisors of the impacted and contralateral sides in the same subject. Likewise, no difference in the severity of root resorption was found between the incisors of impacted side alone and the incisors of the control group. Mesial and vertical inclinations of the impacted canines were negatively related to a lateral incisor's root resorption. No correlations were found between resorption and medial or vertical position of the crown of the canine. The follicle/tooth ratio was significantly related to the mesial inclination of the impacted canine, but not to root resorption. An impacted maxillary canine, after being distanced from the incisor roots, does not seem to be a risk factor for apical root resorption during orthodontic treatment. Copyright © 2012 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  10. Barriers Inhibiting Inquiry-Based Science Teaching and Potential Solutions: Perceptions of Positively Inclined Early Adopters

    Science.gov (United States)

    Fitzgerald, Michael; Danaia, Lena; McKinnon, David H.

    2017-07-01

    In recent years, calls for the adoption of inquiry-based pedagogies in the science classroom have formed a part of the recommendations for large-scale high school science reforms. However, these pedagogies have been problematic to implement at scale. This research explores the perceptions of 34 positively inclined early-adopter teachers in relation to their implementation of inquiry-based pedagogies. The teachers were part of a large-scale Australian high school intervention project based around astronomy. In a series of semi-structured interviews, the teachers identified a number of common barriers that prevented them from implementing inquiry-based approaches. The most important barriers identified include the extreme time restrictions on all scales, the poverty of their common professional development experiences, their lack of good models and definitions for what inquiry-based teaching actually is, and the lack of good resources enabling the capacity for change. Implications for expectations of teachers and their professional learning during educational reform and curriculum change are discussed.

  11. Alveolar bone thickness and lower incisor position in skeletal Class I and Class II malocclusions assessed with cone-beam computed tomography.

    Science.gov (United States)

    Baysal, Asli; Ucar, Faruk Izzet; Buyuk, Suleyman Kutalmis; Ozer, Torun; Uysal, Tancan

    2013-06-01

    To evaluate lower incisor position and bony support between patients with Class II average- and high-angle malocclusions and compare with the patients presenting Class I malocclusions. CBCT records of 79 patients were divided into 2 groups according to sagittal jaw relationships: Class I and II. Each group was further divided into average- and high-angle subgroups. Six angular and 6 linear measurements were performed. Independent samples t-test, Kruskal-Wallis, and Dunn post-hoc tests were performed for statistical comparisons. Labial alveolar bone thickness was significantly higher in Class I group compared to Class II group (p = 0.003). Lingual alveolar bone angle (p = 0.004), lower incisor protrusion (p = 0.007) and proclination (p = 0.046) were greatest in Class II average-angle patients. Spongious bone was thinner (p = 0.016) and root apex was closer to the labial cortex in high-angle subgroups when compared to the Class II average-angle subgroup (p = 0.004). Mandibular anterior bony support and lower incisor position were different between average- and high-angle Class II patients. Clinicians should be aware that the range of lower incisor movement in high-angle Class II patients is limited compared to average- angle Class II patients.

  12. Twin Block appliance with acrylic capping does not have a significant inhibitory effect on lower incisor proclination

    NARCIS (Netherlands)

    van der Plas, Mark Cornelis; Janssen, Krista Ingeborg; Pandis, Nikolaos; Livas, Christos

    Objective: To investigate the effect of acrylic capping, treatment duration, overjet, and lower incisor inclination on the posttreatment tooth position in patients treated with 2 Twin Block (TB) appliance versions. Materials and Methods: Cephalograms of 56 patients with Class II malocclusion (21

  13. The effect of inclined position on stone free rates in patients with lower caliceal stones during SWL session

    Directory of Open Access Journals (Sweden)

    Basri Cakiroglu

    2015-03-01

    Full Text Available Objective: To compare the outcomes of shock wave lithotripsy (SWL combined with inclined position and SWL alone in patients with lower pole calyx stones. Methods: Seven hundred forty patients who underwent SWL treatment for lower pole renal stones with a total diameter of 2 cm or less were prospectively randomized into two groups. They were comparable in terms of age, sex, and stone diameters. Patients with lower calyceal stones (4-20 mm were randomized to SWL (368 patients or SWL with simultaneous inclination (372 patients with 30o head down Trendelenburg position. Shock wave and session numbers were standardized according to stone size. Additional standardized shock waves were given to patients with stone fragments determined by kidney urinary bladder film and ultrasound at weeks 1, 4, 10. Results: The overall stone free rate (SFR was 73% (268/368 in patients with SWL alone and 81% (300/372 in SWL with inclination at the end of 12th week (p = 0.015. No significant adverse events were noted in both treatment groups. Conclusion: Simultaneous inclination of patients during SWL session increase SFR in lower caliceal stones significantly compared to SWL treatment alone.

  14. Optical performance of inclined south-north axis three-positions tracked solar panels

    International Nuclear Information System (INIS)

    Zhong, Hao; Li, Guihua; Tang, Runsheng; Dong, Wenli

    2011-01-01

    In this work, the optical performance of solar panels with a new sun-tracking technique was theoretically investigated based on the proposed mathematical method and monthly horizontal radiation. The mechanism of the investigated sun-tracking is that the attitude angle of solar panels is daily adjusted three times at three fixed positions: eastward, southward, and westward in the morning, noon, and afternoon, respectively, by rotating solar panels about the inclined south-north axis (ISNA-3P sun-tracking). Calculation results showed that, for ISNA-3P tracked solar panels with a yearly fixed tilt-angle of the ISNA, the maximum annual collectible radiation on ISNA-3P tracked solar panels was about 93% of that on a solar panel with 2-axis sun-tracking; whereas for those with the ISNA being yearly adjusted four times at three fixed tilt-angles, it was about 96%. Results also indicated that the attempt to further increase the annual solar gain on ISNA-3P tracked solar panels by seasonally optimizing design of the sun-tracking system for maximizing solar gain in each of four seasons was not efficient, and thus not advisable in practical applications. Optimal parametric designs of such sun-tracking system for maximizing the annual solar gain on solar panels in different cases were also presented. -- Research highlights: → The paper presented a new sun-tracking technique (ISNA-3P) for possible applications in PV generating systems. → Algorithms to estimate daily collectible radiation on the fixed, 2-axis and ISNA-3P tracked solar panels were proposed based on solar geometry and monthly horizontal radiation. → A detailed theoretical study on the optical performance of such tracked solar panels in terms of R 3P-0 and R 3P-2 , the ratios of maximum annual solar gain to that on fixed and 2-axis tracked solar panels; optimal parameters affecting the optical performance of the systems were presented in the different cases. → Results showed that such sun-tracking system

  15. Maxillary incisor retraction: evaluation of different mechanisms

    Directory of Open Access Journals (Sweden)

    Antônio Carlos de Oliveira Ruellas

    2013-04-01

    Full Text Available OBJECTIVE: To mechanically evaluate different systems used for incisors retraction. METHODS: Three different methods for incisors retraction using 0.019 x 0.025-in stainless steel wire were evaluated. The samples were divided into three groups: Group A (retraction arch with 7-mm high vertical hooks; Group G3 (elastic chain attached to the miniimplant and to the 3-mm stainless steel hook soldered to the retraction arch; Group G6 (elastic chain attached to the mini-implant and to the 6-mm stainless steel hook soldered to the retraction arch. A dental mannequin was used for evaluation in order to simulate the desired movements when the device was exposed to a heat source. The analysis of variance (ANOVA and the Tukey test were used (p < 0.05. RESULTS: The results demonstrated that Groups G3 and G6 exhibited less extrusion and less incisor inclination during the retraction phase (p < 0.05. With regard to incisor extrusion, statistically significant differences were observed between Groups A and G3, and between Groups A and G6 (p < 0.05. Regarding incisor inclination, statistically significant differences were observed between the three systems evaluated (p < 0.05. CONCLUSIONS: Arches with 6-mm vertical hooks allow the force to be applied on the center of resistance of the incisors, thus improving mechanical control when compared with the other two systems.

  16. Influence of implant position on clinical crown length and peri-implant soft tissue dimensions at implant-supported single crowns replacing maxillary central incisors

    DEFF Research Database (Denmark)

    Peng, Min; Fei, Wei; Hosseini, Mandana

    2013-01-01

    The aims of the present study were to evaluate the influence of implant position on clinical crown length and marginal soft tissue dimensions at implant-supported single crowns of maxillary central incisors, and to validate the papilla index score (PIS). Twenty-five patients, who had lost one of ...... abutments and did not necessarily result in an increased crown length. The distal implant papilla heightwas obviously shorter, althoughthe mesial papilla height was similar to thatof the healthy dentition.The papilla index score was tested to be a valid index for papilla fill....

  17. Maxillary canine impactions related to impacted central incisors: two case reports.

    Science.gov (United States)

    Bayram, Mehmet; Ozer, Mete; Sener, Ismail

    2007-09-01

    The purpose of this case report is to describe the combined surgical and orthodontic treatment of two cases with an impacted maxillary central incisor and canine in the same quadrant and to discuss the causal relationship between them. The most common causes of canine impactions are usually the result of one or more factors such as a long path of eruption, tooth size-arch length discrepancies, abnormal position of the tooth bud, prolonged retention or early loss of the deciduous canine, trauma, the presence of an alveolar cleft, ankylosis, cystic or neoplastic formation, dilaceration of the root, supernumerary teeth, and odontomas. Although impaction of the maxillary central incisor is almost as prevalent as impacted canines its etiology is different. The principal factors involved in causing the anomaly are supernumerary teeth, odontomas, and trauma. Case #1: A 10.5-year-old girl in the early mixed dentition stage presented with a chief complaint of the appearance of her anterior teeth. She had a Class I skeletal pattern and a history of trauma to the maxillary central incisors at age five with premature exfoliation. Radiographs revealed an impacted upper right central incisor in the region of the nasal floor, delayed eruption of the maxillary permanent central incisor, and the adjacent lateral incisor was inclined toward the edentulous space. Treatment was done in two stages consisting of surgical exposure and traction of the impacted central incisor and fixed orthodontic treatment. Case #2: An 11.5-year-old girl presented for orthodontic treatment with the chief complaint of an unerupted tooth and the appearance of her upper anterior teeth. She was in the late mixed dentition period with a Class III skeletal pattern along with an anterior cross-bite with some maxillary transverse deficiency. The maxillary right canine and central incisor were absent, but the maxillary right deciduous canine was still present. Treatment included arch expansion followed by

  18. Optimal parameters for final position of teeth in space closure in case of a missing upper lateral incisor.

    Science.gov (United States)

    Lombardo, Luca; D'Ercole, Antonio; Latini, Michele Carmelo; Siciliani, Giuseppe

    2014-11-27

    The aim of this study was to provide clinical indications for the correct management of appliances in space closure treatment of patients with agenesis of the upper lateral incisors. Virtual setup for space closure was performed in 30 patients with upper lateral incisor agenesis. Tip, torque and in-out values were measured and compared with those of previous authors. In the upper dentition, the tip values were comparable to those described by Andrews (Am J Orthod 62(3):296-309, 1972), except for at the first premolars, which require a greater tip, and the first molars, a lesser tip. The torque values showed no differences except for at the canines, where it was greater, and the in-out values were between those reported by Andrews and those by Watanabe et al. (The Shikwa Gakuho 96:209-222, 1996) (except for U3 and U4). The following prescriptions are advisable: tip 5°, torque 8° and in-out 2.5 for U1; tip 9°, torque 3° and in-out 3.25 for U3; tip 10°, torque -8° and in-out 3.75 for U4; and tip 5°, torque -8° and in-out 4 for U5. Andrews' prescription is suitable for the lower jaw, except for at L6. It is also advisable to execute selective grinding (1.33±0.5 mm) and extrusion (0.68±0.23 mm) on the upper canine during treatment, and the first premolar requires some intrusion (0.56±0.30 mm).

  19. If Science Teachers Are Positively Inclined Toward Inclusive Education, Why Is It So Difficult?

    Science.gov (United States)

    Spektor-Levy, Ornit; Yifrach, Merav

    2017-08-01

    This paper describes the unique challenges that students with learning disabilities (LD) experience in science studies and addresses the question of the extent to which science teachers are willing and prepared to teach in inclusive classrooms. We employed the theory of planned behavior (TPB), according to which behavioral intentions are a function of individuals' attitudes toward the behavior, their subjective norms, and their perceived control—i.e., their perception of the simplicity and benefits of performing the behavior. The study comprised 215 junior high school science teachers, who answered a TPB-based quantitative questionnaire. Semi-structured interviews were conducted to support and enrich the findings and conclusions. We found that teachers held positive attitudes and were willing to adapt their teaching methods (perceived control), which correlated and contributed to their behavioral intention. In terms of subjective norms, however, they felt a lack of support and ongoing guidance in providing the appropriate pedagogy to meet the needs of students with LD. We therefore recommend that educational policy makers and school management devote attention and resources to providing professional training and appropriate instructional materials and to establishing frameworks for meaningful cooperation between the science teachers and special education staff. This could ensure the efficient cooperation and coordination of all the involved parties and send a positive message of support to the science teachers who are the actual implementers of change.

  20. Lower incisor dentoalveolar compensation and symphysis dimensions among Class I and III malocclusion patients with different facial vertical skeletal patterns.

    Science.gov (United States)

    Molina-Berlanga, Núria; Llopis-Perez, Jaume; Flores-Mir, Carlos; Puigdollers, Andreu

    2013-11-01

    To compare lower incisor dentoalveolar compensation and mandible symphysis morphology among Class I and Class III malocclusion patients with different facial vertical skeletal patterns. Lower incisor extrusion and inclination, as well as buccal (LA) and lingual (LP) cortex depth, and mandibular symphysis height (LH) were measured in 107 lateral cephalometric x-rays of adult patients without prior orthodontic treatment. In addition, malocclusion type (Class I or III) and facial vertical skeletal pattern were considered. Through a principal component analysis (PCA) related variables were reduced. Simple regression equation and multivariate analyses of variance were also used. Incisor mandibular plane angle (P Class I P  =  .03 and Class III P  =  .01) and a positive correlation with LH (Class I P  =  .01 and Class III P  =  .02) in both groups. Within the Class III group, there was a negative correlation between the mandibular plane and LP (P  =  .02). PCA showed that the tendency toward a long face causes the symphysis to elongate and narrow. In Class III, alveolar narrowing is also found in normal faces. Vertical facial pattern is a significant factor in mandibular symphysis alveolar morphology and lower incisor positioning, both for Class I and Class III patients. Short-faced Class III patients have a widened alveolar bone. However, for long-faced and normal-faced Class III, natural compensation elongates the symphysis and influences lower incisor position.

  1. A combined periodontal - prosthetic treatment approach to manage unusual gingival visibility in resting lip position and inversely inclined upper anterior teeth: a case report with discussion.

    Science.gov (United States)

    Biniraj, K R; Janardhanan, Mahija; Sunil, M M; Sagir, Mohammed; Hariprasad, A; Paul, Tony P; Emmatty, Rishi

    2015-03-01

    Excessive gingival visibility during smile is a common esthetic complaint in dentistry, but excessive gingival visibility in resting lip position is relatively uncommon condition. Several exclusive radical to conservative surgical treatment or its combination with orthodontic therapy to treat this condition are within the reach of every patient nowadays. A case report of an excessive gingival visibility because of altered passive eruption along with inversely inclined maxillary anterior teeth is presented here. A relatively simple treatment approach combining periodontal and restorative therapy is used here to achieve the desirable aesthetic results. The gingival exposure resulting from altered passive eruption was completely managed by a gingivectomy, but the inclined appearance of teeth was still an aesthetic complaint. After complete healing of gingivectomy surgery, appropriately designed crowns were given to rectify the inversely inclined appearance. A complete rehabilitation of patient's smile could be achieved, the case was followed up for 3 years and the condition was found satisfactory.

  2. A Combined Periodontal – Prosthetic Treatment Approach to Manage Unusual Gingival Visibility in Resting Lip Position and Inversely Inclined Upper Anterior Teeth: A Case Report with Discussion

    Science.gov (United States)

    Biniraj, K R; Janardhanan, Mahija; Sunil, M M; Sagir, Mohammed; Hariprasad, A; Paul, Tony P; Emmatty, Rishi

    2015-01-01

    Excessive gingival visibility during smile is a common esthetic complaint in dentistry, but excessive gingival visibility in resting lip position is relatively uncommon condition. Several exclusive radical to conservative surgical treatment or its combination with orthodontic therapy to treat this condition are within the reach of every patient nowadays. A case report of an excessive gingival visibility because of altered passive eruption along with inversely inclined maxillary anterior teeth is presented here. A relatively simple treatment approach combining periodontal and restorative therapy is used here to achieve the desirable aesthetic results. The gingival exposure resulting from altered passive eruption was completely managed by a gingivectomy, but the inclined appearance of teeth was still an aesthetic complaint. After complete healing of gingivectomy surgery, appropriately designed crowns were given to rectify the inversely inclined appearance. A complete rehabilitation of patient’s smile could be achieved, the case was followed up for 3 years and the condition was found satisfactory. PMID:25878482

  3. Macrodontic maxillary incisor in alagille syndrome

    Directory of Open Access Journals (Sweden)

    Mauro Cozzani

    2012-01-01

    Full Text Available This case report describes the surgical-orthodontic guided-eruption of a deeply impacted macrodontic maxillary central incisor in a 10-year-old patient with Alagille syndrome (ALGS. In the first stage, orthodontic treatment with fixed appliance on deciduous teeth allowed to create enough space for the eruption of the maxillary right central incisor. The second stage included closed surgical exposure and vertical traction. After impacted tooth erupted in the proper position, accessory periodontal treatment and dental reshaping procedures may be indicated to camouflage macrodontic incisor with the adjacent teeth. This is the first report that presents a patient with ALGS undergoing orthodontic and surgical treatment.

  4. Application of ankle joint adem position combined with foot inclined position in ankle sprain%踝关节正侧位联合足正斜位在足踝扭伤中的应用

    Institute of Scientific and Technical Information of China (English)

    施付强; 胡扬; 刘霞; 汪伟伟

    2015-01-01

    Objective To investigate X-ray examination technique and diagnosis of ankle joint sprain, in order to reduce misdiagnosis rate. Methods There were 8 patients with fractures caused by ankle joint sprain, and they all received ankle joint adem position examination and foot inclined position examination. Examination results were observed. Results Among the 8 patients, there was 1 case with lateral malleolus fracture, whose ankle joint adem position result was worse than foot inclined position, 1 case with lateral malleolus fracture, which was not showed by ankle joint adem position but was clearly showed by foot inclined position, and 1 case with fracture in basilar part of the fifth metatarsal bone, which had ankle joint adem position results better than foot inclined position. Conclusion Application of ankle joint adem position combined with foot inclined position examination can show the fracture line better than single examination by joint adem position or foot inclined position, thereby the coincidence rate of diagnosis can be improved.%目的:探讨踝关节扭伤的X线检查技术及诊断,以降低误诊漏诊率。方法8例足踝扭伤并致骨折的患者,均行踝关节正侧位检查及足正斜位检查,观察检查结果。结果8例患者中,有1例外踝骨折,踝关节正侧位显示不如足正斜位,1例外踝骨折踝关节正侧位未能显示,而足正斜位能清晰显示,1例第五跖骨基底部骨折足正斜位显示不如踝关节正侧位。结论踝关节扭伤患者行踝关节正侧位联合足正斜位检查比单纯踝关节正侧位检查或单纯足正斜位检查能更好的显示骨折线,从而提高诊断符合率。

  5. Molar Incisor Hypomineralisation

    NARCIS (Netherlands)

    Elfrink, M.; Weerheijm, K.L.

    2013-01-01

    Molar Incisor Hypomineralisation (mih) wordt omschreven als een hypomineralisatie (van systemische oorsprong) van één tot vier blijvende eerste molaren, vaak in combinatie met aangedane incisieven. mih-molaren zijn fragieler en cariësgevoeliger dan gewone molaren. Een kenmerk van mih-molaren is een

  6. Molar Incisor Hypomineralisation

    NARCIS (Netherlands)

    Elfrink, M.; Weerheijm, K.L.

    2009-01-01

    Molar Incisor Hypomineralisation (MIH) wordt gedefinieerd als een hypomineralisatie van systemische oorsprong van één tot vier blijvende eerste molaren, vaak in combinatie met aangedane incisieven. MIH-molaren zijn fragieler en cariësgevoeliger dan gewone molaren. Een kenmerk van MIH-molaren is een

  7. Molar Incisor Hypomineralisation

    NARCIS (Netherlands)

    Elfrink, M.; Weerheijm, K.

    2011-01-01

    Molar Incisor Hypomineralisation (mih ) wordt gedefinieerd als een hypomineralisatie van systemische oorsprong van één tot vier blijvende eerste molaren, vaak in combinatie met aangedane incisieven. mih -molaren zijn fragieler en cariësgevoeliger dan gewone molaren. Een kenmerk van mih -molaren is

  8. The effects of impacted premaxillary supernumerary teeth on permanent incisors

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Yun Hoa; Kim, Ji Yeon; Cho, Bong Hae [School of Dentistry, Pusan National University, Yangsan (Korea, Republic of)

    2016-12-15

    The aim of this study was to examine the radiographic features associated with impacted premaxillary supernumerary teeth, to determine the relationship between their characteristics and their effects on permanent incisors, and to investigate the types of orthodontic treatment that patients received after the extraction of impacted supernumerary teeth. The clinical records and radiographs of 193 patients whose impacted premaxillary supernumerary teeth were removed were retrospectively reviewed, and 241 impacted supernumerary teeth were examined. Cone-beam computed tomographic images and panoramic radiographs were examined to determine the number, location, sagittal position, orientation, and morphology of the supernumerary teeth. Their effects on permanent incisors and the orthodontic treatment received by patients after the extraction of the supernumeraries were also investigated. Supernumerary teeth were most frequently observed in the central incisor region, in the palatal position, in the inverted orientation, and were most commonly conical in shape. The most common complication was median diastema, followed by displacement and delayed eruption of the adjacent incisors. Ten (71.4%) of the 14 odontomas showed delayed eruption of the adjacent incisors. Displacement of the incisors was more frequently observed in association with supernumerary teeth with tuberculate or supplemental shapes. Orthodontic traction was most frequently performed after the removal of odontomas. In 32 cases (13.3%), permanent incisors erupted after the orthodontic creation of sufficient space. Median diastema was most common complication. The delayed eruption of incisors was common in supernumerary teeth with a vertical orientation and an odontoma shape.

  9. The effects of impacted premaxillary supernumerary teeth on permanent incisors

    International Nuclear Information System (INIS)

    Jung, Yun Hoa; Kim, Ji Yeon; Cho, Bong Hae

    2016-01-01

    The aim of this study was to examine the radiographic features associated with impacted premaxillary supernumerary teeth, to determine the relationship between their characteristics and their effects on permanent incisors, and to investigate the types of orthodontic treatment that patients received after the extraction of impacted supernumerary teeth. The clinical records and radiographs of 193 patients whose impacted premaxillary supernumerary teeth were removed were retrospectively reviewed, and 241 impacted supernumerary teeth were examined. Cone-beam computed tomographic images and panoramic radiographs were examined to determine the number, location, sagittal position, orientation, and morphology of the supernumerary teeth. Their effects on permanent incisors and the orthodontic treatment received by patients after the extraction of the supernumeraries were also investigated. Supernumerary teeth were most frequently observed in the central incisor region, in the palatal position, in the inverted orientation, and were most commonly conical in shape. The most common complication was median diastema, followed by displacement and delayed eruption of the adjacent incisors. Ten (71.4%) of the 14 odontomas showed delayed eruption of the adjacent incisors. Displacement of the incisors was more frequently observed in association with supernumerary teeth with tuberculate or supplemental shapes. Orthodontic traction was most frequently performed after the removal of odontomas. In 32 cases (13.3%), permanent incisors erupted after the orthodontic creation of sufficient space. Median diastema was most common complication. The delayed eruption of incisors was common in supernumerary teeth with a vertical orientation and an odontoma shape

  10. Extraction of Maxillary Central Incisors: An Orthodontic-Restorative Treatment

    Science.gov (United States)

    Hedayati, Zohreh; Zare, Maryam; Bahramnia, Fateme

    2014-01-01

    Malformed central incisors with poor prognosis could be candidates for extraction especially in crowded dental arches. This case report refers to a 12-year-old boy who suffered from malformed upper central incisors associated with severe attrition. Upper lateral incisors were positioned palatally and canines were rotated and positioned in the high buccal area. The patient had class II malocclusion and space deficiency in both dental arches. Due to incisal wear and malformed short maxillary central incisors and the need for root canal therapy with a major crown build-up, these teeth were extracted. The maxillary lateral incisors were substituted. Thus the maxillary canines were substituted for lateral incisors and the first premolars were substituted for canines. In the lower dental arch the first bicuspids were extracted. Composite resin build-up was performed on the maxillary lateral incisors and canines. This allowed for the crowding and the malocclusion to be corrected. Subsequent gingivectomy improved the patient's gingival margins and smile esthetics one month after orthodontic therapy. PMID:25400954

  11. Chair time saving method for treatment of an impacted maxillary central incisor with 15-month follow-up

    Directory of Open Access Journals (Sweden)

    Saeed Noorollahian

    2018-01-01

    Full Text Available Maxillary permanent incisors have a major role in facial esthetics. Impaction of them has great adverse effect on smile and causes serious concerns in patient and parents. Physical barriers (e.g., overretained primary teeth, supernumerary teeth, and pathologic lesions, space problems, developmental abnormalities, altered eruption sequence, trauma, palatal clefts, and genetics can act as etiologic factors. Currently, the conventional technique to treatment of impacted teeth consists of a combined orthodontic and surgical approach, to guide the impacted teeth in a constant position and surrounded by normal hard and soft tissues. Treatment is challenging because of some limitations such as patient's age, cooperation, anchorage, and mechanotherapy possibilities. Hence, sophisticated treatment planning is crucial. A 9-year-old girl with horizontally impacted maxillary left central incisor treated with surgical exposure and closed orthodontic forced eruption with 2 × 4 partial setup fixed appliances. Force was applied with 0.014 inch nickel–titanium wire as elastic overlay and handmade ligated bracket. To save chair time in each appointment, the overlay was activated by twisting of ligature wire extensions around it. After 16-month treatment, impacted incisor emerged in oral cavity, with accepted alignment and inclination. Handmade ligated bracket with ligature wire extensions is useful for the treatment of impacted teeth. Due to easy activation of overlay in this method, chair time become short in each appointment.

  12. Managing the severely proclined maxillary anteriors by extracting traumatized right maxillary central incisor

    Directory of Open Access Journals (Sweden)

    Mahesh Jain

    2014-01-01

    Full Text Available A 14-year-old girl reported with severely proclined maxillary anterior teeth with fractured and discolored right maxillary central incisor with questionable prognosis. Autotransplantation of premolar to replace central incisor was considered a risky option as patient was 14-year-old with presence of advanced root development of premolar. The immediate placement of the prosthetic implant was also not possible because of patient′s age. Therefore, it was decided to use the space obtained by extracting questionable maxillary right central incisor for orthodontic purpose and also sacrificing the healthy premolar is invariably an excessive biological cost for a modest functional and aesthetic gain. Hence, the treatment plan for this case includes extraction of right maxillary central incisor and left maxillary first premolar, movement of right maxillary lateral incisor mesially, achieving normal axial inclination of maxillary anteriors with normal overjet and overbite. Mandibular arch was treated nonextraction due to congenitally missing central incisors with presence of normally inclined lower anteriors thereby maintaining Angles class I occlusion. Tipping, usually, seen in Begg mechanotherapy was used for our advantage to correct severely proclined maxillary anteriors with simultaneous bite opening mechanics. Case was completed in 19 months and posttreatment records including photographs, radiographs and study models were made. Begg wrap around the retainer was placed in the maxillary arch allowing natural settling of occlusion.

  13. The rat incisor in toxicologic pathology

    NARCIS (Netherlands)

    Kuijpers, M.H.M.; Kooij, A.J. van de; Slootweg, P.J.

    1996-01-01

    Microscopic examination of the incisors of rats and mice may reveal toxicologically significant changes. First, the incisor morphology reflects the nutritional status of the animal: fluctuations of mineral metabolism and vitamin availability are disclosed by the rodent incisors, because the incisors

  14. Treatment of traumatized maxillary central incisors

    Directory of Open Access Journals (Sweden)

    Jun Kuo

    2011-12-01

    Full Text Available Traumatic injury to the upper anterior teeth is not uncommon in young children. Dental ankylosis frequently occurs when teeth are traumatically luxated or replanted after being avulsed. Orthodontic movement of a traumatized tooth is difficult, especially when treating an ankylosed tooth without surgical luxation and distraction osteogenesis. This report describes a case of a patient with class I crowded malocclusion and labially displaced and intruded traumatized maxillary incisors. The protruded traumatized incisors were successfully brought to an acceptable position with acceptable gingival esthetics through the use of simple orthodontic traction combined with first-premolar extraction. An acceptable overbite and overjet were achieved within 14 months after completion of orthodontic treatment.

  15. Six upper incisors: what's next?

    Science.gov (United States)

    Berneburg, Mirjam; Meller, Christian

    2016-01-01

    This case report describes our therapeutic approach taken in a girl with eruption disturbance of the upper anterior teeth. Two supernumerary teeth were involved, which required a combination of orthodontic and surgical treatment. The initial situation in the upper anterior segment was characterized by two supernumerary mesial incisors, ectopic eruption of the distally located lateral incisors, and crowded tooth buds in the canine areas. Key decisions had to be made as to whether any teeth needed to be extracted and, if so, regarding the timing and sites of extraction. Removing teeth too early would have preempted a complete assessment of tooth quality, whereas late extraction would have carried a risk of eruption disturbance. Once the distal lateral incisors had erupted, the supernumerary mesial incisors were extracted and the central incisors (initially located in between) mesialized with a bracket appliance. Following space closure and mesialization of the lateral incisors, a functional appliance was used. Tooth 13 was erupting, while tooth 23 was displaced and subsequently aligned as part of the final bracket treatment. To successfully treat eruption disturbances, a careful diagnostic workup is essential, including informative radiographs, personalized treatment planning, and correct decision-making as to whether teeth need to be extracted and regarding the timing and sites of extraction. Finally, the eruption of the canines should be monitored.

  16. A randomized clinical trial comparing mandibular incisor proclination produced by fixed labial appliances and clear aligners.

    Science.gov (United States)

    Hennessy, Joe; Garvey, Thérèse; Al-Awadhi, Ebrahim A

    2016-09-01

    To compare the mandibular incisor proclination produced by fixed labial appliances and third generation clear aligners. Patients underwent a course of orthodontic treatment using either fixed labial appliances or clear aligners (Invisalign). Mandibular incisor proclination was measured by comparing pretreatment and near-end treatment lateral cephalograms. Eligibility criteria included adult patients with mild mandibular incisor crowding (clear aligner group. Baseline characteristics were similar for both groups: Fixed appliance mean crowding was 2.1 ± 1.3 mm vs clear aligner mean crowding, 2.5 ± 1.3 mm; pretreatment mean mandibular incisor inclination for the fixed appliance group was 90.8 ± 5.4° vs 91.6 ± 6.4° for the clear aligner group. Fixed appliances produced 5.3 ± 4.3° of mandibular incisor proclination. Clear aligners proclined the mandibular incisors by 3.4 ± 3.2°. The difference between the two groups was not statistically significant (P > .05). There was no difference in the amount of mandibular incisor proclination produced by clear aligners and fixed labial appliances in mild crowding cases.

  17. Bilateral Maxillary Central Incisor Impaction associated with Developing Supernumerary Premolars in the Mandibular Arch

    Directory of Open Access Journals (Sweden)

    Mitali Mishra

    2014-01-01

    We report a case of 15-year-old girl with bilaterally impacted supernumeraries in the premaxilla region associated with asymptomatic impacted developing supernumerary premolars in the mandibular arch. The supernumeraries of premaxilla region impeded the eruption of the permanent maxillary central incisors. The impacted supernumerary tooth was surgically removed and brackets bonded to the central incisors to apply orthodontic extrusive force which brought the central incisors down to their proper position in the dental arch.

  18. The radiographic localization of unerupted maxillary incisors and supernumeraries

    International Nuclear Information System (INIS)

    Kim, Jae Duk; Lee, Chang Yul; You, Choong Hyun

    2003-01-01

    To evaluate the use of the vertical tube shift from a panoramic film and a periapical film to localize unerupted maxillary incisors and supernumeraries. The total of 103 displaced maxillary incisors or embedded supernumeraries were examined in this study. The vertical tube shift technique with panoramic and periapical radiography by normal projection taken and compared to localize the position of the embedded maxillary incisors or supernumeraries by a radiologist and 5 general dentists. The gold standard used for the radiographic comparisons was the true position of the embedded tooth as confirmed by horizontal tube shift technique using three periapical radiographs. The general dentist examiners were instructed on the use of the modified acronym 'SLDOBU' by the radiologist as it pertains to panoramic radiographs as the principle of vertical tube shift. All of the embedded maxillary incisors and supernumeraries were successfully located using the vertical tube shift from a panoramic and a maxillary anterior periapical radiograph by the radiologist and 5 general dentists. The use of a panoramic film with a periapical film combination for a vertical tube shift can be useful to localize unerupted maxillary incisors and supernumeraries.

  19. Measurement of defects on the wall by use of the inclination angle of laser slit beam and position tracking algorithm of camera

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Hwan; Yoon, Ji Sup; Jung, Jae Hoo; Hong, Dong Hee; Park, Gee Yong

    2001-01-01

    In this paper, a method of measuring the size of defects on the wall and restructuring the defect image is proposed based on the estimation algorithm of a camera orientation which uses the declination angle of the line slit beam. To reconstruct the image, an algorithm of estimating the horizontally inclined angle of CCD camera is presented. This algorithm adopts a 3-dimensional coordinate transformation of the image plane where both the LASER beam and the original image of the defects exist. The estimation equation is obtained by using the information of the beam projected on the wall and the parameters of this equation are experimentally obtained. With this algorithm, the original image of the defect can be reconstructed into the image which is obtained by a camera normal to the wall. From the result of a series of experiment shows that the measuring accuracy of the defect is within 0.5% error bound of real defect size under 30 degree of the horizontally inclined angle. Also, the accuracy is deteriorates with the error rate of 1% for every 10 degree increase of the horizontally inclined angle. The estimation error increases in the range of 30{approx}50 degree due to the existence of dead zone of defect depth, and defect length can not be measured due to the disappearance of image data above 70 degree. In case of under water condition, the measuring accuracy is also influenced due to the changed field of view of both the camera and the laser slit beam caused by the refraction rate in the water. The proposed algorithm provides the method of reconstructing the image taken at any arbitrary camera orientation into the image which is obtained by a camera normal to the wall and thus it enables the accurate measurement of the defect lengths only by using a single camera and a laser slit beam.

  20. Vehicle with inclinable caterpillars

    International Nuclear Information System (INIS)

    Carra, O.; Delevallee, A.

    1991-01-01

    Vehicle has a body with propulsion assemblies that drive caterpillar tracks. When a propulsion unit inclines about its articulation axis it is aided by an advance movement of the caterpillar track in the opposite direction of rotation [fr

  1. Clinical and radiographic evaluation of maxillary central incisors exposure in patients undergoing maxillary advancement

    Directory of Open Access Journals (Sweden)

    Guilherme dos Santos Trento

    2015-12-01

    Full Text Available Abstract Introduction: Patients with dentofacial deformities may undergo orthodontic or orthodontic-surgical treatment. Both modalities can affect esthetics. Objective: This study aims to evaluate clinical and radiographic changes in exposure of maxillary central incisors occurring after orthognathic surgery for maxillary advancement. Methods: A total of 17 patients who underwent orthognathic surgery for maxillary advancement between September, 2010 and July, 2011 were selected. Exposure of maxillary central incisors was evaluated clinically and by lateral cephalograms. Measurements were taken one week before and three months after surgery. Data were paired in terms of sex, age, nasolabial angle, height and thickness of the upper lip, the amount of maxillary advancement, clinical exposure and inclination of maxillary central incisor by statistical tests (CI 95%. Results: After maxillary advancement, incisor clinical exposure had increased even with relaxed lips and under forced smile. Moreover, there was a mean increase of 23.33% revealed by lateral cephalograms. There was an inverse correlation between upper lip thickness and incisors postsurgical exposure revealed by radiographic images (p = 0.002. Conclusions: Significant changes in the exposure of maxillary central incisors occur after maxillary advancement, under the influence of some factors, especially lip thickness.

  2. Rethinking incisor size and diet in anthropoids: diet, incisor wear and incisor breadth in the African apes.

    Science.gov (United States)

    McCollum, Melanie A

    2007-07-01

    In a seminal study Hylander (1975) concluded that the length of the incisor row in catarrhines considered frugivores is longer relative to body mass than in those classified as folivores. Assuming that large fruits require greater incisal processing than do leaves, stems, berries, and seeds, he argued that the larger incisors of frugivores increased their resistance to wear. The present analysis examines diet, incisor wear, and incisor crown breadth in cranial samples of western lowland gorillas and chimpanzees. Incisor wear rate was assessed on the basis of the extent of incisor crown reduction observed at sequential stages of first molar wear. Incisor metrics were obtained from the unworn teeth of juveniles. Results suggest that incisor wear is greater in the more folivorous western lowland gorillas than in more frugivorous chimpanzees. Moreover, incisor crown dimensions do not differ appreciably among African apes. These findings fail to support the hypothesis that slower wear rates are associated with broader incisor crowns, and raise new questions regarding the significance of incisor row length in anthropoids. (c) 2007 Wiley-Liss, Inc.

  3. Stresses generated by two zygomatic implant placement techniques associated with conventional inclined anterior implants

    Directory of Open Access Journals (Sweden)

    Paulo H.T. Almeida

    2018-06-01

    Full Text Available Purpose: To make a comparative evaluation, by means of the finite element method, of the stress generated on supporting tissues and prosthetic system components, using zygomatic implants with the exteriorized and extramaxillary techniques, and different placement positions, associated either with inclined anterior implants, or those without inclination. Materials and methods: Eight (8 tridimensional models were created to represent the clinical situations being researched, using the dataset of scanned images of an edentulous model. The implants and prosthetic components were photographed on millimeter paper and inserted into Rhinoceros 3D modeling computer software. From the measurements made on the image, the virtual models were made. The application force was distributed on the occlusal surface of the working side of the left maxillary first molar, first and second premolars, and incisal regions of the central incisor, simulating the occlusal load during mastication, in a total of 150 N. Results: The extramaxillary technique presented considerable variation in increased tension on the prosthesis screws and bone tissue. In the exteriorized technique, the highest tension values occurred in the region of the ridge, and the lowest, on the zygomatic process; the absence of cantilever reduced the stress on bone tissue in almost all regions. Conclusion: The exteriorized technique was shown to be more favorable to the distribution of stresses on the micro-unit screws and bone tissue, with the model with zygomatic implant placed in the region of the first molar and inclined anterior implant presenting the best results. Keywords: Zygomatic implants, Atrophic maxilla, Finite element analysis, Cantilever, Inclined implant

  4. Esthetic periodontal surgery for impacted dilacerated maxillary central incisors.

    Science.gov (United States)

    Wei, Yu-Ju; Lin, Yi-Chun; Kaung, Shou-Shin; Yang, Shue-Fen; Lee, Shyh-Yuan; Lai, Yu-Lin

    2012-10-01

    Clinicians do not frequently see impacted dilacerated maxillary incisors in their patients. When they do, there are several diagnostic and management challenges for correcting root dilacerations. An unfavorable esthetic outcome might occur as a result of soft-tissue complications during surgical eruption procedures. We present 2 patients with an impacted and dilacerated maxillary central incisor. Computed tomography scans with 3-dimensional reformation were used to accurately assess the positions of the dilacerated teeth, the degree of dilaceration, and the stage of root formation. The therapy primarily involved 2-stage crown exposure surgery combined with orthodontic traction. An apicoectomy was performed on 1 dilacerated tooth; the other exhibited pulp vitality. This article highlights the periodontal surgical strategies for the esthetic management of inverted crowns. Through periodontal plastic surgery and interdisciplinary cooperation, the impacted dilacerated central incisors were properly aligned, and successful esthetic results were achieved. Copyright © 2012 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  5. Mandibular incisor apicoectomy in a Canadian Beaver.

    Science.gov (United States)

    Steenkamp, Gerhard; Venter, Leon; Crossley, David; Buss, Peter

    2009-01-01

    A 52-month-old Canadian beaver was presented for treatment of lip trauma resulting from overgrowth of the right mandibular incisor tooth following earlier loss of the right maxillary incisor tooth. Extraction of the affected tooth was considered, but rejected due to the length of the embedded portion of rodent mandibular incisor teeth. The lip injury was managed by crown reduction (odontoplasty) of the overgrowing incisor tooth pending a more permanent treatment plan. A 2-cm apicoectomy of the right mandibular incisor tooth was performed to arrest growth of the tooth when the beaver was 82-months-old. The remainder of the tooth continued to erupt and was completely expelled during a 9-month period with one additional odontoplasty being required. The beaver continued to feed normally with just the left maxillary and mandibular incisor teeth until its death at 118-months, with odontoplasty performed twice on the remaining incisor teeth during the 30-months following exfoliation.

  6. Removable orthodontic appliance with nickel-titanium spring to reposition the upper incisors in an autistic patient.

    Science.gov (United States)

    Saito, Kan; Jang, Insan; Kubota, Kazumi; Hoshino, Tomonori; Hotokezaka, Hitoshi; Yoshida, Noriaki; Fujiwara, Taku

    2013-01-01

    A newly designed removable appliance with a shape-memory wire was used for the orthodontic treatment of the anterior teeth in an 11-year-old child who had autism and intellectual disability. The device was designed to reduce the lateral incisor crossbite and the central incisors' labial rotation. The child was treated for 1 year with this removable appliance. Tooth movement was analyzed using cephalograms and surface data were derived from study models. This device proved to be very durable. The lateral incisor crossbite was corrected, and the inclination of the upper central incisors and the interincisal angle were improved. This appliance exerts light and continuous orthodontic force, without requiring any adjustments of the spring wire. The appliance also facilitated orthodontic treatment in a child with intellectual disability in whom treatment with a standard orthodontic device would be unsuitable. ©2012 Special Care Dentistry Association and Wiley Periodicals, Inc.

  7. Orthodontic movement of a maxillary incisor through the midpalatal suture: a case report.

    Science.gov (United States)

    Garib, Daniela Gamba; Janson, Guilherme; dos Santos, Patrícia Bittencourt Dutra; de Oliveira Baldo, Taiana; de Oliveira, Gabriela Ulian; Ishikiriama, Sérgio Kiyoshi

    2012-03-01

    Orthodontic space closure is a treatment alternative when a maxillary central incisor is missing. The objective of this report was to present an unusual treatment in which a right maxillary central incisor was moved through the midpalatal suture to replace the absent contralateral tooth. The biologic aspects and clinical appearance of the recontoured lateral and central incisors were analyzed. The position of the examined teeth and the appearance of the surrounding soft tissues were satisfactory; however, the upper midline frenulum deviated to the left. The incisor was successfully moved with no obvious detrimental effects as observed on the final radiographs. In the radiographic and tomographic examinations, the midline suture seemed to have followed the tooth movement. The patient expressed satisfaction with the results. It was concluded that orthodontic movement of the central incisor to replace a missing contralateral tooth is a valid treatment option, and the achievement of an esthetic result requires an interdisciplinary approach, including restorative dentistry and periodontics.

  8. Mandibular Symmetrical Bilateral Canine-Lateral Incisors Transposition: Its Early Diagnosis and Treatment Considerations

    Directory of Open Access Journals (Sweden)

    Yehoshua Shapira

    2016-01-01

    Full Text Available Bilateral mandibular tooth transposition is a relatively rare dental anomaly caused by distal migration of the mandibular lateral incisors and can be detected in the early mixed dentition by radiographic examination. Early diagnosis and interceptive intervention may reduce the risk of possible transposition between the mandibular canine and lateral incisor. This report illustrates the orthodontic management of bilateral mandibular canine-lateral incisor transposition. Correct positioning of the affected teeth was achieved on the left side while teeth on the right side were aligned in their transposed position. It demonstrates the outcome of good alignment of the teeth in the dental arch.

  9. Mandibular Symmetrical Bilateral Canine-Lateral Incisors Transposition: Its Early Diagnosis and Treatment Considerations.

    Science.gov (United States)

    Shapira, Yehoshua; Finkelstein, Tamar; Kadry, Rana; Schonberger, Shirley; Shpack, Nir

    2016-01-01

    Bilateral mandibular tooth transposition is a relatively rare dental anomaly caused by distal migration of the mandibular lateral incisors and can be detected in the early mixed dentition by radiographic examination. Early diagnosis and interceptive intervention may reduce the risk of possible transposition between the mandibular canine and lateral incisor. This report illustrates the orthodontic management of bilateral mandibular canine-lateral incisor transposition. Correct positioning of the affected teeth was achieved on the left side while teeth on the right side were aligned in their transposed position. It demonstrates the outcome of good alignment of the teeth in the dental arch.

  10. Effect of implant position, angulation, and attachment height on peri-implant bone stress associated with mandibular two-implant overdentures: a finite element analysis.

    Science.gov (United States)

    Hong, Hae Ryong; Pae, Ahran; Kim, Yooseok; Paek, Janghyun; Kim, Hyeong-Seob; Kwon, Kung-Rock

    2012-01-01

    The aim of this study was to analyze and compare the level and distribution of peri-implant bone stresses associated with mandibular two-implant overdentures with different implant positions. Mathematical models of mandibles and overdentures were designed using finite element analysis software. Two intraosseous implants and ball attachment systems were placed in the interforaminal region. The overdenture, which was supported by the two implants, was designed to withstand bilateral and unilateral vertical masticatory loads (total 100 N). In all, eight types of models, which differed according to assigned implant positions, height of attachments, and angulation, were tested: MI (model with implants positioned in the lateral incisor sites), MC (implants in canine sites), MP (implants in premolar sites), MI-Hi (greater height of attachments), MC-M (canine implants placed with mesial inclination), MC-D (canine implants placed with distal inclination), MC-B (canine implants placed with buccal inclination), and MC-L (canine implants placed with lingual inclination). Peri-implant bone stress levels associated with overdentures retained by lateral incisor implants resulted in the lowest stress levels and the highest efficiency in distributing peri-implant stress. MI-Hi showed increased stress levels and decreased efficiency in stress distribution. As the implants were inclined, stress levels increased and the efficiency of stress distribution decreased. Among the inclined models, MC-B showed the lowest stress level and best efficiency in stress distribution. The lowest stress and the best stability of implants in mandibular two-implant overdentures were obtained when implants were inserted in lateral incisor areas with shorter attachments and were placed parallel to the long axes of the teeth.

  11. Cone Beam Computed Tomography-based Evaluation of the Anterior Teeth Position Changes obtained by Passive Self-ligating Brackets.

    Science.gov (United States)

    Rhoden, Fernando K; Maltagliati, Liliana Á; de Castro Ferreira Conti, Ana C; Almeida-Pedrin, Renata R; Filho, Leopoldino C; de Almeida Cardoso, Maurício

    2016-08-01

    The objective of this study was to evaluate the anterior teeth position changes obtained by passive self-ligating brackets using cone beam computed tomography (CBCT). Twenty patients with a mean age of 16.5 years, class I malocclusion, constricted maxillary arch, and teeth crowding above 5 mm were enrolled in this study, and treated by passive orthodontic self-ligating brackets. A sequence of stainless steel thermoset wire was implemented with ending wire of 0.019" × 0.025". The CBCT and dental casts were obtained prior to the installation of orthodontic appliances (T1), and 30 days after rectangular steel wire 0.019" × 0.025" installation (T2). The measurements in CBCT were performed with the Anatomage software, and the dental casts were evaluated with a digital caliper rule with an accuracy of 0.01 mm. The CBCT data demonstrated mean buccal inclination of the upper and lower central incisors ranging from 6.55° to 7.24° respectively. The upper and lower lateral incisors ranged from 4.90° to 8.72° respectively. The lower canines showed an average increase of 3.88° in the buccal inclination and 1.96 mm in the transverse intercuspal distance. The upper canines showed a negative inclination with mean average of -0.36°, and an average increase of 0.82 mm in the transverse distance, with negative correlation with the initial crowding. Treatment with passive self-ligating brackets without obtaining spaces increases buccal inclination of the upper and lower incisors with no correlation with the amount of initial teeth crowding. The intercanine distance tends to a small increase showing different inclinations between the arches. When taking into account the self-ligating brackets, the amount of initial dental crowding is not a limitation factor that could increase the buccal inclination of the anterior teeth.

  12. Lower molar and incisor displacement associated with mandibular remodeling.

    Science.gov (United States)

    Baumrind, S; Bravo, L A; Ben-Bassat, Y; Curry, S; Korn, E L

    1997-01-01

    The purpose of this study was to quantify the amount of alveolar modeling at the apices of the mandibular incisor and first molar specifically associated with appositional and resorptive changes on the lower border of the mandible during growth and treatment. Cephalometric data from superimpositions on anterior cranial base, mandibular implants of the Björk type, and anatomical "best fit" of mandibular border structures were integrated using a recently developed strategy, which is described. Data were available at annual intervals between 8.5 and 15.5 years for a previously described sample of approximately 30 children with implants. The average magnitudes of the changes at the root apices of the mandibular first molar and central incisor associated with modeling/remodeling of the mandibular border and symphysis were unexpectedly small. At the molar apex, mean values approximated zero in both anteroposterior and vertical directions. At the incisor apex, mean values approximated zero in the anteroposterior direction and averaged less than 0.15 mm/year in the vertical direction. Standard deviations were roughly equal for the molar and the incisor in both the anteroposterior and vertical directions. Dental displacement associated with surface modeling plays a smaller role in final tooth position in the mandible than in the maxilla. It may also be reasonably inferred that anatomical best-fit superimpositions made in the absence of implants give a more complete picture of hard tissue turnover in the mandible than they do in the maxilla.

  13. Torque Control During Intrusion on Upper Central Incisor in Labial and Lingual bracket System - A 3D Finite Element Study.

    Science.gov (United States)

    Pol, Tejas R; Vandekar, Meghna; Patil, Anuradha; Desai, Sanjana; Shetty, Vikram; Hazarika, Saptarshi

    2018-01-01

    The aim of present study was to investigate the difference of torque control during intrusive force on upper central incisors with normal, under and high torque in lingual and labial orthodontic systems through 3D finite element analysis. Six 3D models of an upper right central incisor with different torque were designed in Solid Works 2006. Software ANSYS Version 16.0 was used to evaluate intrusive force on upper central incisor model . An intrusive force of 0.15 N was applied to the bracket slot in different torque models and the displacements along a path of nodes in the upper central incisor was assessed. On application of Intrusive force on under torqued upper central incisor in Labial system produce labial crown movement but in Lingual system caused lingual movement in the apical and incisal parts. The same intrusive force in normal-torqued central incisor led to a palatal movement in apical and labial displacement of incisal edge in Lingual system and a palatal displacement in apical area and a labial movement in the incisal edge in Labial systemin. In overtorqued upper central incisor, the labial crown displacement in Labial system is more than Lingual system. In labial and lingual system on application of the same forces in upper central incisor with different inclinations showed different responses. The magnitudes of torque Loss during intrusive loads in incisors with normal, under and over-torque were higher in Labial system than Lingual orthodontic appliances. Key words: FEM, lingual orthodontics, intrusion, torque control, labial bracket systems.

  14. Evaporation of inclined water droplets

    Science.gov (United States)

    Kim, Jin Young; Hwang, In Gyu; Weon, Byung Mook

    2017-01-01

    When a drop is placed on a flat substrate tilted at an inclined angle, it can be deformed by gravity and its initial contact angle divides into front and rear contact angles by inclination. Here we study on evaporation dynamics of a pure water droplet on a flat solid substrate by controlling substrate inclination and measuring mass and volume changes of an evaporating droplet with time. We find that complete evaporation time of an inclined droplet becomes longer as gravitational influence by inclination becomes stronger. The gravity itself does not change the evaporation dynamics directly, whereas the gravity-induced droplet deformation increases the difference between front and rear angles, which quickens the onset of depinning and consequently reduces the contact radius. This result makes the evaporation rate of an inclined droplet to be slow. This finding would be important to improve understanding on evaporation dynamics of inclined droplets. PMID:28205642

  15. Bidispersive-inclined convection

    Science.gov (United States)

    Mulone, Giuseppe; Straughan, Brian

    2016-01-01

    A model is presented for thermal convection in an inclined layer of porous material when the medium has a bidispersive structure. Thus, there are the usual macropores which are full of a fluid, but there are also a system of micropores full of the same fluid. The model we employ is a modification of the one proposed by Nield & Kuznetsov (2006 Int. J. Heat Mass Transf. 49, 3068–3074. (doi:10.1016/j.ijheatmasstransfer.2006.02.008)), although we consider a single temperature field only. PMID:27616934

  16. Negative and positive externalities in intergroup conflict: exposure to the opportunity to help the outgroup reduces the inclination to harm it.

    Science.gov (United States)

    Weisel, Ori

    2015-01-01

    Outgroup hate, in the context of intergroup conflict, can be expressed by harming the outgroup, but also by denying it help. Previous work established that this distinction-whether the externality on the outgroup is negative or positive-has an important effect on the likelihood of outgroup hate emerging as a motivation for individual participation in intergroup conflict. The current work uses a within-subject design to examine the behavior of the same individuals in intergroup conflict with negative and positive externalities on the outgroup. Each participant made two choices, one for each type of externality, and the order was counter balanced. The main results are that (1) behavior is fairly consistent across negative and positive externalities, i.e., the tendency to display outgroup hate by harming the outgroup is correlated with the tendency to display outgroup hate by avoiding to help the outgroup; (2) People are reluctant to harm the outgroup after being exposed to the opportunity to help it; (3) Groupness-the degree to which people care about their group and its well-being-is related to outgroup hate only when participants encounter the opportunity to harm the outgroup first (before they encounter the opportunity to help it). In this setting the relationship between groupness and outgroup hate spilled over to the subsequent interaction, where it was possible to help the outgroup. When the opportunity to help the outgroup was encountered first, groupness was not related to outgroup hate.

  17. Negative and positive externalities in intergroup conflict: Exposure to the opportunity to help the outgroup reduces the inclination to harm it

    Directory of Open Access Journals (Sweden)

    Ori eWeisel

    2015-10-01

    Full Text Available Outgroup hate, in the context of intergroup conflict, can be expressed by harming the outgroup, but also by denying it help.Previous work established that this distinction---whether the externality on the outgroup is negative or positive---has an important effect on the likelihood of outgroup hate emerging as a motivation for individual participation in intergroup conflict.The current work uses a within-subject design to examine the behaviour of the same individuals in intergroup conflict with negative and positive externalities on the outgroup.Each participant made two choices, one for each type of externality, and the order was counter balanced.The main results are that(1 behaviour is fairly consistent across negative and positive externalities, i.e., the tendency to display outgroup hate by harming the outgroup is correlated with the tendency to display outgroup hate by avoiding to help the outgroup; (2 People are reluctant to harm the outgroup after being exposed to the opportunity to help it; (3 emph{Groupness}---the degree to which people care about their group and its well-being---is related to outgroup hate only when participants encounter the opportunity to harm the outgroup first (before they encounter the opportunity to help it. In this setting the relationship between groupness and outgroup hate spilled over to the subsequent interaction, where it was possible to help the outgroup. When the opportunity to help the outgroup was encountered first, groupness was not related to outgroup hate.

  18. Biomechanical considerations in mandibular incisor extraction cases.

    Science.gov (United States)

    Rachala, Madhukar Reddy; Aileni, Kaladhar Reddy; Dasari, Arun Kumar; Sinojiya, Jay

    2015-01-01

    Mandibular incisor extraction can be regarded as a valuable treatment option in certain malocclusions to obtain excellence in orthodontic results in terms of function, aesthetics and stability. This treatment alternative is indicated in clinical situations like mild to moderate class III malocclusion, mild anterior mandibular tooth size excess, periodontally compromised teeth, ectopic eruption of mandibular incisor and minimal openbite tendencies. Unlike in premolar extraction cases, space closure in mandibular incisor extraction cases is unique in which the extraction space will be in the middle of the arch. The end result of space closure in these cases should be well aligned, upright, anterior teeth with parallel roots and the goal can be achieved with the bodily tooth movement through proper application of biomechanics. The purpose of this article is to explain the biomechanics of space closure in mandibular incisor extraction cases.

  19. Particle transport in inclined annuli

    Energy Technology Data Exchange (ETDEWEB)

    Kurtzhals, Erik

    1993-12-31

    A new model for the formation and behaviour of deposits in inclined wellbores is formulated. The annular space is divided into two layers, separated by a distinct plane boundary. While the lower layer is taken to consist of closely packed cuttings, the upper layer is presumed to behave as a pure fluid. A force balance for the lower layer decides whether it is stationary or slides in the upwards- or downwards direction. The position of the deposit surface is governed by the fluid shear stress at the deposit surface. The proposed model represents a major improvement compared to an earlier model. The predictions from the SCSB-model are in good qualitative agreement with experimental results obtained by the author, and results published by research groups in the U.S.A., United Kingdom and Germany. The quantitative agreement is variable, presumably because the SCSB-model is a somewhat simplified description of particle behaviour in inclined annuli. However, the model provides a clearer understanding of the physical background for previously published experimental results. In order to couple the theoretical work with experimental observations, an annular flow loop has been constructed. A characteristic feature in the flow loop design is the application of load cells, which permits determination of the annular particle content at steady state as well as under transient conditions. Due to delays in the constructional work, it has only been possible to perform a limited number of investigations in the loop. However, the results produced are in agreement with results published by other research groups. (au)

  20. Particle transport in inclined annuli

    Energy Technology Data Exchange (ETDEWEB)

    Kurtzhals, Erik

    1994-12-31

    A new model for the formation and behaviour of deposits in inclined wellbores is formulated. The annular space is divided into two layers, separated by a distinct plane boundary. While the lower layer is taken to consist of closely packed cuttings, the upper layer is presumed to behave as a pure fluid. A force balance for the lower layer decides whether it is stationary or slides in the upwards- or downwards direction. The position of the deposit surface is governed by the fluid shear stress at the deposit surface. The proposed model represents a major improvement compared to an earlier model. The predictions from the SCSB-model are in good qualitative agreement with experimental results obtained by the author, and results published by research groups in the U.S.A., United Kingdom and Germany. The quantitative agreement is variable, presumably because the SCSB-model is a somewhat simplified description of particle behaviour in inclined annuli. However, the model provides a clearer understanding of the physical background for previously published experimental results. In order to couple the theoretical work with experimental observations, an annular flow loop has been constructed. A characteristic feature in the flow loop design is the application of load cells, which permits determination of the annular particle content at steady state as well as under transient conditions. Due to delays in the constructional work, it has only been possible to perform a limited number of investigations in the loop. However, the results produced are in agreement with results published by other research groups. (au)

  1. Compound odontome with unerupted permanent incisor

    Directory of Open Access Journals (Sweden)

    Mahfujul Haq Khan

    2011-01-01

    Full Text Available Odontomas are mixed odontogenic tumors composed of both epithelial and mesenchymal dental hard tissues. They are usually asymptomatic and are often discovered during routine radiography. A case of odontoma in a 21 year old man is described who presented with delayed eruption of upper central and lateral incisor teeth. The odontome was surgically removed followed by re-implantation of preserved extracted lateral incisor and a porcelain crown. Ibrahim Med. Coll. J. 2011; 5(1: 29-31

  2. Impacted maxillary central incisor: surgical exposure and orthodontic treatment.

    Science.gov (United States)

    Pinho, Teresa; Neves, Manuel; Alves, Célia

    2011-08-01

    This case report describes the treatment of a patient with a horizontally impacted maxillary central incisor, a canine in the same quadrant, and an inclusion tendency. Due to severe crowing in the maxilla and the Class II molar relationship on the impaction side, a 2-stage treatment plan was developed. In the first stage, the right first premolar and deciduous canine were extracted; this allowed enough space for the eruption of the maxillary right permanent canine. The second stage included surgical exposure and traction of the impacted central incisor with a fixed orthodontic appliance. An excisional uncovering technique was needed to expose the impacted incisor. After it erupted, an apically positioned partial-thickness flap was used to add keratinized attached gingiva in the area surrounding the crown, initially located in an area of unattached gingiva. The patient finished treatment with a normal and stable occlusion between the maxillary and mandibular arches and an adequate width of attached gingiva. Copyright © 2011 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  3. Three-dimensional anatomy of equine incisors: tooth length, enamel cover and age related changes

    Science.gov (United States)

    2013-01-01

    Background Equine incisors are subjected to continuous occlusal wear causing multiple, age related changes of the extragingival crown. It is assumed that the occlusal wear is compensated by continued tooth elongation at the apical ends of the teeth. In this study, μCT-datasets offered the opportunity to analyze the three-dimensional appearance of the extra- and intraalveolar parts of the enamel containing dental crown as well as of the enamel-free dental root. Multiple morphometric measurements elucidated age related, morphological changes within the intraalveolar part of the incisors. Results Equine incisors possess a unique enamel cover displaying large indentations on the mesial and distal sides. After eruption tooth elongation at the apical end outbalances occlusal wear for two to four years resulting in increasing incisor length in this period of time. Remarkably, this maximum length is maintained for about ten years, up to a tooth age of 13 to 15 years post eruption. Variances in the total length of individual teeth are related to different Triadan positions (central-, middle- and corner incisors) as well as to the upper and lower arcades. Conclusion Equine incisors are able to fully compensate occlusal wear for a limited period of time. However, after this ability ceases, it is expected that a diminished intraalveolar tooth length will cause massive changes in periodontal biomechanics. The time point of these morphodynamic and biomechanical changes (13 to 15 years post eruption) occurs in coincidence with the onset of a recently described destructive disease of equine incisor (equine odontoclastic tooth resorption and hypercementosis) in aged horses. However, further biomechanical, cell biological and microbiological investigations are needed to elucidate a correlation between age related changes of incisor morphology and this disease. PMID:24321365

  4. Development and homology of the incisor teeth in the rabbit

    International Nuclear Information System (INIS)

    Muylle, S.; Simoens, P.; Lauwers, H.

    1996-01-01

    The morphology and development of the incisors were investigated stercomicroscopically, radiographically and by means of serial histologic sections in fetal, juvenile and adult New Zealand White rabbits. A vestigial and a major incisor develop on both sides of the upper and of the lower jaw, while a diphyodont minor incisor is located caudal to the major incisor on both sides of the upper jaw. The present study describes a unique case of incisor polyodontia in an adult wild rabbit, that exhibited all the characteristics of a typical atavistic dentition. From these observations it was deduced that the vestigial and the major incisors in the rabbit are monophyodont and correspond to the first and second incisors respectively, while the minor diphyodont incisor in the upper jaw is homologous with the third incisor

  5. Deontological and utilitarian inclinations in moral decision making: a process dissociation approach.

    Science.gov (United States)

    Conway, Paul; Gawronski, Bertram

    2013-02-01

    Dual-process theories of moral judgment suggest that responses to moral dilemmas are guided by two moral principles: the principle of deontology states that the morality of an action depends on the intrinsic nature of the action (e.g., harming others is wrong regardless of its consequences); the principle of utilitarianism implies that the morality of an action is determined by its consequences (e.g., harming others is acceptable if it increases the well-being of a greater number of people). Despite the proposed independence of the moral inclinations reflecting these principles, previous work has relied on operationalizations in which stronger inclinations of one kind imply weaker inclinations of the other kind. The current research applied Jacoby's (1991) process dissociation procedure to independently quantify the strength of deontological and utilitarian inclinations within individuals. Study 1 confirmed the usefulness of process dissociation for capturing individual differences in deontological and utilitarian inclinations, revealing positive correlations of both inclinations to moral identity. Moreover, deontological inclinations were uniquely related to empathic concern, perspective-taking, and religiosity, whereas utilitarian inclinations were uniquely related to need for cognition. Study 2 demonstrated that cognitive load selectively reduced utilitarian inclinations, with deontological inclinations being unaffected. In Study 3, a manipulation designed to enhance empathy increased deontological inclinations, with utilitarian inclinations being unaffected. These findings provide evidence for the independent contributions of deontological and utilitarian inclinations to moral judgments, resolving many theoretical ambiguities implied by previous research. (c) 2013 APA, all rights reserved.

  6. Stress field of a dislocating inclined fault

    Energy Technology Data Exchange (ETDEWEB)

    Huang, F.; Wang, T.

    1980-02-01

    Analytical expressions are derived for the stress field caused by a rectangular dislocating fault of an arbitrary dip in a semi-infinite elastic medium for the case of unequal Lame constants. The results of computations for the stress fields on the ground surface of an inclined strike-slip and an inclined dip-slip fault are represented by contour maps. The effects of Poisson Ratio of the medium, the dip angle, upper and lower boundaries of the faults on the stress field at surface have been discussed. As an application, the contour maps for shear stress and hydrostatic stress of near fields of the Tonghai (1970), Haicheng (1975) and Tangshan (1976) earthquakes have been calculated and compared with the spatial distributions of strong aftershocks of these earthquakes. It is found that most of the strong aftershocks are distributed in the regions of tensional stress, where the hydrostatic stress is positive.

  7. Stress field of a dislocating inclined fault

    Energy Technology Data Exchange (ETDEWEB)

    Huang, F.; Wang, T.

    1980-02-01

    In this paper, analytical expressions of the stress field given rise by a rectangular dislocating fault of an arbitrary dip in a semi-infinite elastic medium for the case of unequal Lame constants are derived. The results of computations for the stress fields on the ground surface of an inclined strike-slip and an inclined dip-slip fault are represented by contour maps. The effects of the Poisson Ratio of the medium, the dip angle, upper and lower boundaries of the faults on the stress field at the surface have been discussed. As an application, the contour maps for shear stress and hydrostatic stress of near fields of the Tonghai (1970), Haicheng, (1975) and Tangshan (1976) earthquakes have been calculated and compared with the spatial distributions of strong aftershocks of these earthquakes. It is found that most of the strong aftershocks are distributed in the regions of tensional stress where the hydrostatic stress is positive.

  8. Molar Incisor Hypomineralization, Prevalence, and Etiology

    Directory of Open Access Journals (Sweden)

    Sulaiman Mohammed Allazzam

    2014-01-01

    Full Text Available Aim. To evaluate the prevalence and possible etiological factors associated with molar incisor hypomineralization (MIH among a group of children in Jeddah, Saudi Arabia. Methods. A group of 8-12-year-old children were recruited (n=267  from the Pediatric Dental Clinics at the Faculty of Dentistry, King Abdulaziz University. Children had at least one first permanent molar (FPM, erupted or partially erupted. Demographic information, children’s medical history, and pregnancy-related data were obtained. The crowns of the FPM and permanent incisors were examined for demarcated opacities, posteruptive breakdown (PEB, atypical restorations, and extracted FPMs. Children were considered to have MIH if one or more FPM with or without involvement of incisors met the diagnostic criteria. Results. MIH showed a prevalence of 8.6%. Demarcated opacities were the most common form. Maxillary central incisors were more affected than mandibular (P=0.01. The condition was more prevalent in children with history of illnesses during the first four years of life including tonsillitis (P=0.001, adenoiditis (P=0.001, asthma (P=0.001, fever (P=0.014, and antibiotics intake (P=0.001. Conclusions. The prevalence of MIH is significantly associated with childhood illnesses during the first four years of life including asthma, adenoid infections, tonsillitis, fever, and antibiotics intake.

  9. Deciduous molar hypomineralization and molar incisor hypomineralization

    NARCIS (Netherlands)

    Elfrink, M.E.C.; ten Cate, J.M.; Jaddoe, V.W.V.; Hofman, A.; Moll, H.A.; Veerkamp, J.S.J.

    2012-01-01

    This study was embedded in the Generation R Study, a population-based prospective cohort study from fetal life until young adulthood. This study focused on the relationship between Deciduous Molar Hypomineralization (DMH) and Molar Incisor Hypomineralization (MIH). First permanent molars develop

  10. [Upper lateral incisor with 2 canals].

    Science.gov (United States)

    Fabra Campos, H

    1991-01-01

    Clinical case summary of the patient with an upper lateral incisor with two root canals. The suspicion that there might be an anatomic anomaly in the root that includes a complex root canal system was made when an advanced radicular groove was detected in the lingual surface or an excessively enlarged cingulum.

  11. Incisors as digging tools in molerats (Bathyergidae)

    African Journals Online (AJOL)

    1998-03-26

    Xa and Vb) at which the upper and lower incisors (lines a- ..... JARVIS. JU.M., BENNETT. N.C. 1991. Introducing the Alriean mole-rats (family Bathyergidae). In: The biology of the naked mole-rat: 66 - 96. (Eds) Sherman. R. W ..

  12. Restoration of a fractured central incisor.

    Science.gov (United States)

    Olson, Bradley J

    2012-03-01

    The treatment of a traumatically damaged single central incisor poses significant challenges relative to function and esthetics to the restoring clinician. Providing a good long-term prognosis is paramount when determining whether to maintain or extract a structurally compromised tooth. Successful restoration demands timely and thorough risk assessment along with excellent communication with both the patient and the laboratory fabricating the restoration.

  13. Influence of shovel-shaped incisors on the dental arch crowding in Mongolian females.

    Science.gov (United States)

    Hasegawa, Yuh; Terada, Kazuto; Kageyama, Ikuo; Tsukada, Shin-ichi; Uzuka, Satoshi; Nakahara, Rizako; Nakahara, Sen

    2009-08-01

    The aim of this study was to investigate the influences of shovel-shaped incisors on the dental arch crowding in the samples of modern young female adult Mongolians (belonging to the Khalkha-Mogol grouping) ranged between 18.5 and 25.0 years, with a mean age of 20.7 years. Materials in this study comprised of 33 dental casts. Plaster replicas of the A.S.U. system plaques were used to facilitate standardization in scoring and classify shoveling regarding both upper central and lateral incisors. Dimensions of the dental arch namely, overjet, overbite, arch depth, arch width and irregularity index were measured. The correlation between the shovel shape of the central incisor and the lateral incisor was highly significant. Significantly relations were found between the grades of shoveling and the mesiodistal diameters of upper first molars and lower incisors. Positive correlation was admitted between the shoveling and upper arch depth anterior, and upper arch depth. It may be considered that the grades of shoveling are indirectly related with upper and/or lower anterior crowding. Although crowding is looks like an expression of disharmony between teeth and alveolar arch, it may be caused by multiple etiologic factors interacted directly and/or indirectly.

  14. Comparison of the physiological properties of human periodontal-masseteric reflex evoked by incisor and canine stimulation

    Directory of Open Access Journals (Sweden)

    Hiroko eOhmori

    2012-06-01

    Full Text Available Introduction: The present study was designed to clarify whether the bilateral cooperation in the human periodontal-masseteric reflex (PMR differs between central incisors and canines. Methods: Surface array electrodes were placed on the bilateral masseter muscles to simultaneously record the firing activities of single motor units from both sides in 7 healthy adults. During light clenching, mechanical stimulation was applied to the right maxillary central incisor and canine to evoke the PMR. Unitary activity was plotted with respect to the background activity and firing frequency. The slope of the regression line (sRL and the correlation coefficient (CC between the central incisor and canine and the lateral differences between these values were compared. Results: There were significant differences in the sRL and CC, as well as lateral differences, between the central incisor- and canine-driven PMR. Discussion: These results suggest that the PMR differs depending on both the tooth position and laterality.

  15. Pool Boiling CHF in Inclined Narrow Annuli

    International Nuclear Information System (INIS)

    Kang, Myeong Gie

    2010-01-01

    Pool boiling heat transfer has been studied extensively since it is frequently encountered in various heat transfer equipment. Recently, it has been widely investigated in nuclear power plants for application to the advanced light water reactors designs. Through the review on the published results it can be concluded that knowledge on the combined effects of the surface orientation and a confined space on pool boiling heat transfer is of great practical importance and also of great academic interest. Fujita et al. investigated pool boiling heat transfer, from boiling inception to the critical heat flux (CHF, q' CHF ), in a confined narrow space between heated and unheated parallel rectangular plates. They identified that both the confined space and the surface orientation changed heat transfer much. Kim and Suh changed the surface orientation angles of a downward heating rectangular channel having a narrow gap from the downward-facing position (180 .deg.) to the vertical position (90 .deg.). They observed that the CHF generally decreased as the inclination angle (θ ) increased. Yao and Chang studied pool boiling heat transfer in a confined heat transfer for vertical narrow annuli with closed bottoms. They observed that when the gap size ( s ) of the annulus was decreased the effect of space confinement to boiling heat transfer increased. The CHF was occurred at much lower value for the confined space comparing to the unconfined pool boiling. Pool boiling heat transfer in narrow horizontal annular crevices was studied by Hung and Yao. They concluded that the CHF decreased with decreasing gap size of the annuli and described the importance of the thin film evaporation to explain the lower CHF of narrow crevices. The effect of the inclination angle on the CHF on countercurrent boiling in an inclined uniformly heated tube with closed bottoms was also studied by Liu et al. They concluded that the CHF reduced with the inclination angle decrease. A study was carried out

  16. Efeitos dos fios de nivelamento de níquel-titânio e de aço inoxidável na posição dos incisivos inferiores Effects of nickel-titanium and stainless steel leveling wires on the position of mandibular incisors

    Directory of Open Access Journals (Sweden)

    Ricardo Moresca

    2011-10-01

    Full Text Available OBJETIVO: estudar os efeitos do nivelamento realizado com fios de NiTi termoativado e de aço inoxidável, avaliando-se as possíveis alterações na posição dos incisivos inferiores, em casos com extrações, correlacionando com o tempo de tratamento. MÉTODOS: a amostra foi composta de 36 indivíduos, de ambos os sexos, leucodermas brasileiros, com idade média inicial de 15 anos e 5 meses, portadores de más oclusões de Classes I e II, distribuídos em dois grupos. No Grupo 1 (n=17, o nivelamento foi realizado com a sequência 1, utilizando-se três fios - 0,016" e 0,019"x0,025" de NiTi termoativado, e 0,019"x0,025" de aço inoxidável. No Grupo 2 (n=19, foi testada a sequência 2, na qual foram utilizados apenas fios de aço inoxidável (0,014"; 0,016"; 0,018"; 0,020" e 0,019"x0,025" com torque passivo nos incisivos inferiores. Os dados foram coletados utilizando-se o método cefalométrico computadorizado e comparados pelo teste t de Student com o nível de significância de 5%. RESULTADOS: no Grupo 1, os incisivos inferiores inclinaram-se para lingual, com movimento significativo apenas da coroa (1,6mm. No Grupo 2, os incisivos inferiores permaneceram estáveis. Não houve alteração vertical em nenhum dos grupos. CONCLUSÕES: a sequência 2 proporcionou um melhor controle dos incisivos inferiores, não alterando suas posições iniciais, enquanto a sequência 1 permitiu a expressão do torque da prescrição utilizada, levando a uma inclinação lingual desses dentes. O tempo de tratamento foi menor utilizando-se a sequência 1. As variações biomecânicas estudadas apresentaram vantagens e desvantagens que devem ser conhecidas e ponderadas pelo ortodontista no planejamento do caso.OBJECTIVE: To study the effects of the leveling phase performed with heat activated NiTi and stainless steel archwires evaluating the possible changes in lower incisors position in extraction cases, as well as its correlation with treatment time. METHODS

  17. Radiographic technique and brackets affect measurements of proximal enamel thickness on mandibular incisors

    NARCIS (Netherlands)

    Ang, Amy Giok Phing; Steegmans, Pauline Antoinette Josephine; Kerdijk, Wouter; Livas, Christos; Ren, Yijin

    2017-01-01

    Objective: To investigate the influence of radiographic film and tube positioning, the presence and the size of brackets on in vitro measurements of proximal enamel thickness of mandibular incisors on periapical radiographs aimed to aid planning of interproximal enamel reduction procedures in

  18. Molar incisor hypomineralization: current research evidences

    Directory of Open Access Journals (Sweden)

    Manikandan Ekambaram

    2016-06-01

    Full Text Available Molar-Incisor Hypomineralization (MIH is a condition of systemic origin that involves one to four first permanent molar teeth and often associated with affected incisors. Although several associations to prenatal/perinatal childhood medical conditions have been reported, the etiology of MIH still remains unclear. The degree of enamel hypomineralization in the affected teeth can vary and the clinical problems associated with the teeth include increased susceptibility to caries, rapid wear, and post-eruptive enamel breakdown. Affected teeth are extremely challenging to treat as the enamel is porous, sensitive and treating clinicians might encounter great difficulty in achieving profound anaesthesia. The first part of thispresentation will give an update on prevalence, potential etiological factors, and management strategies of this condition. The second part of the presentation will cover a systematic review results on bonding strategies to hypomineralized enamel.

  19. Assessment of crown angulations, crown inclinations, and tooth size discrepancies in a South Indian population

    Directory of Open Access Journals (Sweden)

    Geeta Maruti Doodamani

    2011-01-01

    Full Text Available Aims and Objective: The aim of this study was to assess crown angulations, crown inclinations, and tooth size discrepancy in a sample population from Davangere, South India. Materials and Methods: One hundred adults (50 male and 50 female of age 18-30 years, with Angle′s class I ideal occlusion and balanced profiles, were selected for the study. Study models were prepared and crown angulations and crown inclinations were measured using a customized protractor device. Bolton′s analysis was used to measure the tooth size discrepancies. Results: Maxillary and mandibular teeth had less crown angulations. Maxillary and mandibular incisors and maxillary molars showed increased crown inclinations, whereas mandibular molars and premolars had less crown inclinations than the original Andrews sample. The mean maxillary and mandibular tooth size ratios, overall and anterior, were similar to Bolton′s ratios. Conclusions: The finding of this study indicates that there are possible racial and ethnic factors contributing to variations in crown angulations and crown inclinations.

  20. [Sequence orthodontic treatment of impacted dilacerated maxillary central incisors].

    Science.gov (United States)

    Zheng, Yi; Pang, Xuannai; Nan, Lan; Mo, Shuixue

    2012-06-01

    To explore an effective orthodontic method for treating impacted dilacerated maxillary central incisors. 12 impacted teeth of 11 cases were chosen. The position of the impacted teeth and the relations with neighbour tissues were assessed by X-ray images, oral examination and plaster model, etc. The impacted teeth were induced to erupt with the closed-eruption technique and fixed orthodontic appliances, root canal therapy, apicoectomy and prosthetic treatment. 12 impacted teeth were moved into arches, and the occlusal relationship was normal. There were no root resorption or conglutination in those impacted teeth. The labial impacted teeth of nine cases had bigger labial crown torsion. The root apexes of four impacted teeth were palpable under mucosa of the labial sulcus and operated by root canal therapy and apicoectomy. One of them received prosthetic treatment. Others (five cases) hadn't accepted root canal therapy, and were observed temporarily. The effects of two palatal impacted teeth was stable. It was a good method to expand indication with sequence orthodontic treatment. The impacted dilacerated maxillary central incisors could be aligned with good esthetical and functional effect.

  1. Inclination Mixing in the Classical Kuiper Belt

    Science.gov (United States)

    Volk, Kathryn; Malhotra, Renu

    2011-07-01

    We investigate the long-term evolution of the inclinations of the known classical and resonant Kuiper Belt objects (KBOs). This is partially motivated by the observed bimodal inclination distribution and by the putative physical differences between the low- and high-inclination populations. We find that some classical KBOs undergo large changes in inclination over gigayear timescales, which means that a current member of the low-inclination population may have been in the high-inclination population in the past, and vice versa. The dynamical mechanisms responsible for the time variability of inclinations are predominantly distant encounters with Neptune and chaotic diffusion near the boundaries of mean motion resonances. We reassess the correlations between inclination and physical properties including inclination time variability. We find that the size-inclination and color-inclination correlations are less statistically significant than previously reported (mostly due to the increased size of the data set since previous works with some contribution from inclination variability). The time variability of inclinations does not change the previous finding that binary classical KBOs have lower inclinations than non-binary objects. Our study of resonant objects in the classical Kuiper Belt region includes objects in the 3:2, 7:4, 2:1, and eight higher-order mean motion resonances. We find that these objects (some of which were previously classified as non-resonant) undergo larger changes in inclination compared to the non-resonant population, indicating that their current inclinations are not generally representative of their original inclinations. They are also less stable on gigayear timescales.

  2. First contact: understanding the relationship between hominoid incisor curvature and diet.

    Science.gov (United States)

    Deane, Andrew

    2009-03-01

    Accurately interpreting fossil primate dietary behaviour is necessary to fully understand a species' ecology and connection to its environment. Traditional methods developed to infer diet from hominoid teeth successfully group taxa into broad dietary categories (i.e., folivore, frugivore) but often fail to represent the range of dietary variability characteristic of living apes. This oversimplification is not only a consequence of poor resolution, but may also reflect the use of similar fallback resources by closely related taxa with dissimilar diets. This study demonstrates that additional dietary specificity can be achieved using a morphometric approach to hominoid incisor curvature. High-resolution polynomial curve fitting (HR-PCF) was used to quantify the incisor curvatures of closely related hominoid taxa that have dissimilar diets but similar morphological adaptations to specific keystone resources (e.g., Gorilla gorilla beringei vs. G. g. gorilla). Given the key role of incisors in food processing, it is reasonable to assume that these teeth will be at least partially influenced by the unique selective pressures imposed by the mechanical loading specific to individual diets. Results from this study identify a strong correlation between hominoid dietary proportions and incisor linear dimensions and curvature, indicating that more pronounced incisor curvature is positively correlated with higher levels of frugivory. Hard-object frugivores have the greatest mesiodistal and cervico-incisal curvature and dedicated folivores have the least curved incisors. Mixed folivore/frugivores are morphological intermediates between dedicated folivores and hard- and soft-object frugivores. Mesiodistal curvature varied only in the degree of curvature; however, cervico-incisal curvature was shown to differ qualitatively between more frugivorous and more folivorous taxa. In addition to identifying a greater range of dietary variability among hominoids, this study also

  3. Cognitive self-affirmation inclination : An individual difference in dealing with self-threats

    NARCIS (Netherlands)

    Pietersma, Suzanne; Dijkstra, Arie

    The current research shows that people differ in their inclination to use positive self-images when their self is threatened (i.e., cognitive self-affirmation inclination, CSAI). Just as self-affirmation manipulations do, the use of positive self-images induces open mindedness towards threatening

  4. Effects of fixed functional therapy on tongue and hyoid positions and posterior airway.

    Science.gov (United States)

    Ozdemir, Fulya; Ulkur, Feyza; Nalbantgil, Didem

    2014-03-01

    To evaluate how therapy with a fixed functional appliance affects airway dimensions, dentoalveolar changes, and tongue and hyoid positions. A retrospective study was carried out on 46 pre- and posttreatment lateral cephalometric radiographs of 23 post-peak Class II patients (12 girls, 11 boys) treated with a Forsus Fatigue Resistant Device (FRD) appliance. The radiographies were taken at the start and at the end of Forsus FRD appliance therapy when a Class I or overcorrected Class I canine and molar relationship was achieved. The process took an average of 5 months 13 days ± 1 month 4 days. Skeletal and dental parameters were measured using Dolphin software, and the sagittal airway area was measured by AutoCAD software. Analyses of the pre- and posttreatment means revealed that there was no statistically significant skeletal correction of the sagittal malocclusion; increase of lower incisor inclination, decrease of upper incisor inclination, decrease of interincisal angle, and rotation of occlusal plane all contributed to the reduction of overjet. The tongue area and intermaxillary space area increased in response to these dentoalveolar changes; however, there was no statistically significant change in the hyoid position or the oropharyngeal area between the two time points. The dentoalveolar changes produced by Forsus FRD appliance did not cause any significant posterior airway changes in young adult patients.

  5. Fused upper central incisors: management of two clinical cases

    OpenAIRE

    Sfasciotti, Gian Luca; Marini, Roberta; Bossù, Maurizio; Ierardo, Gaetano; Annibali, Susanna

    2012-01-01

    This paper reports the management of two clinical cases, in which the upper right central incisor was fused with a supernumerary tooth and the upper left central incisor was macrodontic. A radiographic examination revealed that the fused teeth had two separate roots. Hemisectioning of the fused teeth was performed, the supernumerary portion was extracted and the remaining part was reshaped to remove any sharp margins and to achieve a normal morphology. The macrodontic central incisors were no...

  6. Compound odontoma associated with impacted maxillary incisors

    Directory of Open Access Journals (Sweden)

    S Sreedharan

    2012-01-01

    Full Text Available Odontomas are considered to be the most common odontogenic tumors of the oral cavity. Some authors consider it as malformations rather than true neoplasms. The exact etiology of odontomes is still not known. Most odontomes are asymptomatic and are discovered during routine radiographic investigations. Odontomes generally cause disturbances in the eruption of the teeth, most commonly delayed eruption or deflection. The present report describes the surgical management of a case of compound odontoma in a 10-year-old boy who presented with a complaint of swelling in the maxillary right anterior region and retained deciduous incisors. The related literature is also being reviewed in this article.

  7. Tenebrio beetles use magnetic inclination compass

    Science.gov (United States)

    Vácha, Martin; Drštková, Dana; Půžová, Tereza

    2008-08-01

    Animals that guide directions of their locomotion or their migration routes by the lines of the geomagnetic field use either polarity or inclination compasses to determine the field polarity (the north or south direction). Distinguishing the two compass types is a guideline for estimation of the molecular principle of reception and has been achieved for a number of animal groups, with the exception of insects. A standard diagnostic method to distinguish a compass type is based on reversing the vertical component of the geomagnetic field, which leads to the opposite reactions of animals with two different compass types. In the present study, adults of the mealworm beetle Tenebrio molitor were tested by means of a two-step laboratory test of magnetoreception. Beetles that were initially trained to memorize the magnetic position of the light source preferred, during the subsequent test, this same direction, pursuant geomagnetic cues only. In the following step, the vertical component was reversed between the training and the test. The beetles significantly turned their preferred direction by 180°. Our results brought until then unknown original findings that insects, represented here by the T. molitor species, use—in contrast to another previously researched Arthropod, spiny lobster—the inclination compass.

  8. Hypomineralized Second Primary Molars as Predictor of Molar Incisor Hypomineralization

    Science.gov (United States)

    Negre-Barber, A.; Montiel-Company, J. M.; Boronat-Catalá, M.; Catalá-Pizarro, M.; Almerich-Silla, J. M.

    2016-01-01

    Molar incisor hypomineralization (MIH) is a developmental defect of dental enamel that shares features with hypomineralized second primary molars (HSPM). Prior to permanent tooth eruption, second primary molars could have predictive value for permanent molar and incisor hypomineralization. To assess this possible relationship, a cross-sectional study was conducted in a sample of 414 children aged 8 and 9 years from the INMA cohort in Valencia (Spain). A calibrated examiner (linear-weighted Kappa 0.83) performed the intraoral examinations at the University of Valencia between November 2013 and 2014, applying the diagnostic criteria for MIH and HSPM adopted by the European Academy of Paediatric Dentistry. 100 children (24.2%) presented MIH and 60 (14.5%) presented HSPM. Co-occurrence of the two defects was observed in 11.1% of the children examined. The positive predictive value was 76.7% (63.9–86.6) and the negative predictive value 84.7% (80.6–88.3). The positive likelihood ratio (S/1-E) was 10.3 (5.9–17.9) and the negative likelihood ratio (1-S/E) 0.57 (0.47–0.68). The odds ratio was 18.2 (9.39–35.48). It was concluded that while the presence of HSPM can be considered a predictor of MIH, indicating the need for monitoring and control, the absence of this defect in primary dentition does not rule out the appearance of MIH. PMID:27558479

  9. Brain malformation in single median maxillary central incisor

    DEFF Research Database (Denmark)

    Kjaer, I; Wagner, Aa; Thomsen, L L

    2009-01-01

    Clinical and radiographic examinations and MR scan of a 12-year-old girl with SMMCI (single median maxillary central incisor) showed impaired growth and a midline defect involving the central incisor, cranium and the midline structures in the brain, falx cerebri and pituitary gland. She had a sev...

  10. Orthodontic intervention of an impacted upper left central incisor due ...

    African Journals Online (AJOL)

    A fixed orthodontic appliance was used to facilitate traction and correction of malalignement of the impacted upper left central incisor.Treatment outcome: Successful removal of the odontoma, full exposure of the crown of upper left central incisor and good alignment on the arch were achieved. Crowding on the upper and ...

  11. Molar incisor hypomineralisation: clinical management of the young patient.

    LENUS (Irish Health Repository)

    Daly, Dympna

    2009-04-01

    Molar incisor hypomineralisation (MIH) is a common developmental condition resulting in enamel defects in first permanent molars and permanent incisors. It presents at eruption of these teeth. Early diagnosis is essential since rapid breakdown of tooth structure may occur, giving rise to acute symptoms and complicated treatment. The purpose of this article is to review MIH and illustrate its clinical management in young children.

  12. Prevalence of shovel-shaped incisors in Saudi Arabian dental patients.

    Science.gov (United States)

    Saini, T S; Kharat, D U; Mokeem, S

    1990-10-01

    The prevalence of maxillary incisor shoveling was studied radiographically in 990 Saudi patients. According to the radiomorphologic characteristics, a new classification was developed and shovel teeth were categorized. The findings of this study showed 9% shovel-shaped incisors; among those, 4% were central incisors and 5% were lateral incisors. Frequency of dens invaginatus occurrence with the shovel-shaped incisors was also investigated. Eight percent of shovel-shaped incisors showed presence of dens invaginatus. Prevalence was found to be 4% in central shovel-shaped incisors, whereas that in lateral shovel-shaped incisors was 11%.

  13. Angle Class I malocclusion treated with lower incisor extraction.

    Science.gov (United States)

    Barbosa, Vanessa Leal Tavares

    2013-01-01

    In planning orthodontic cases that include extractions as an alternative to solve the problem of negative space discrepancy, the critical decision is to determine which teeth will be extracted. Several aspects must be considered, such as periodontal health, orthodontic mechanics, functional and esthetic alterations, and treatment stability. Despite controversies, extraction of teeth to solve dental crowding is a therapy that has been used for decades. Premolar extractions are the most common, but there are situations in which atypical extractions facilitate mechanics, preserve periodontal health and favor maintenance of the facial profile, which tends to unfavorably change due to facial changes with age. The extraction of a lower incisor, in selected cases, is an effective approach, and literature describes greater post-treatment stability when compared with premolar extractions. This article reports the clinical case of a patient with Angle Class I malocclusion and upper and lower anterior crowding, a balanced face and harmonious facial profile. The presence of gingival and bone recession limited large orthodontic movements. The molars and premolars were well occluded, and the discrepancy was mainly concentrated in the anterior region of the lower dental arch. The extraction of a lower incisor in the most ectopic position and with compromised periodontium, associated with interproximal stripping in the upper and lower arches, was the alternative of choice for this treatment, which restored function, providing improved periodontal health, maintained facial esthetics and allowed finishing with a stable and balanced occlusion. This case was presented to the Brazilian Board of Orthodontics and Dentofacial Orthopedics (BBO), as part of the requirements for obtaining the BBO Diplomate title.

  14. STRATIFICATION TECHNIQUE IN MAXILLARY ANTERIOR INCISORS RESTORATION

    Directory of Open Access Journals (Sweden)

    Janet Kirilova

    2014-08-01

    Full Text Available Background: Because of their main characteristics: transparency, opalescence and color density, the tooth structures are extremely difficult to restore by means of completely inconspicuous restorations of the natural tooth tissue characteristics. The aim is to show successful aesthetic restoration of III Class dental lesions in upper incisors by means of high quality composites. Materials and method: A female patient visited the clinic being not satisfied with the esthetics of her front teeth. The intraoral examination showed previous restorations and carious lesions in 12, 11, 21, 22. After defining the tooth color a silicone key was made. The treatment was performed under anesthesia, the existing restorations were removed and the carious lesions in teeth 11, 12, 21, 22 were treated with restorations using Vanini edge preparation. The teeth were restored by means of stratification technique. After etching and rinsing, bonding was applied for 20 sec. and then polymerized. After fixing the silicone key enamel shade was applied and then dentine shades UD2, UD3, UD4 of 0.5mm thickness each. The polymerization was done layer by layer. Applied were 10 to 15 layers in total. The composite material was preheated in oven up to 55. Teeth 21 and 22 are restored with Enamel Plus HRi (Micerium. Results and Discussion: Excellent aesthetics is achieved with composite material. They have enamel and dentine shades and allow high quality aesthetics. The polishing is excellent in Enamel Plus HRi (Micerium which is typical for this type of composite. The result of the carious lesion treatment in this patient is real improvement of the dental appearance of her anterior incisors. Conclusion: Materials show excellent aesthetic results due to their characteristics and the stratification technique used.

  15. Vitality preservation of an anomalous maxillary central incisor after endodontic therapy.

    Science.gov (United States)

    Kaufman, A Y; Kaffe, I; Littner, M M

    1984-06-01

    Endodontic treatment of a case of fused immature central incisor with a supernumerary tooth with dens in dente is described. Although a chronic dentoalveolar abscess was diagnosed, vitality test signs were positive. Treatment consisted of pulpotomy with calcium hydroxide paste; after 2 1/2 months a permanent root canal filling was placed in the amputated part. Follow-up 2 years postoperatively indicated that the tooth has maintained its vitality. The periapical area is completely healed, and apical closure is evident.

  16. Fused upper central incisors: management of two clinical cases.

    Science.gov (United States)

    Sfasciotti, Gian Luca; Marini, Roberta; Bossù, Maurizio; Ierardo, Gaetano; Annibali, Susanna

    2011-03-01

    This paper reports the management of two clinical cases, in which the upper right central incisor was fused with a supernumerary tooth and the upper left central incisor was macrodontic. A radiographic examination revealed that the fused teeth had two separate roots. Hemisectioning of the fused teeth was performed, the supernumerary portion was extracted and the remaining part was reshaped to remove any sharp margins and to achieve a normal morphology. The macrodontic central incisors were not treated. At 12-months post-surgery there were no periodontal problems and no hypersensitivity. Orthodontic treatment was performed to appropriately align the maxillary teeth and to correct the malocclusion.

  17. Slipping and Rolling on an Inclined Plane

    Science.gov (United States)

    Aghamohammadi, Cina; Aghamohammadi, Amir

    2011-01-01

    In the first part of the paper, using a direct calculation two-dimensional motion of a particle sliding on an inclined plane is investigated for general values of friction coefficient ([mu]). A parametric equation for the trajectory of the particle is also obtained. In the second part of the paper, the motion of a sphere on the inclined plane is…

  18. Multidisciplinary Restoration of Traumatized and Displaced Maxillary Central Incisor by Bent Wire System-A Novel Approach.

    Science.gov (United States)

    Sasalawad, Shilpa S; Jogani, Vivek; Pai, Suryakanth M; Chour, Rashmi C; Balehosur, Deepti V

    2016-11-01

    Management of traumatic injuries to teeth is a challenge to dental practice, as it occurs when dentists are least prepared for it. The direction and the force of the object or the fall significantly affects the diagnosis, treatment plan and therefore the outcome of the treatment. These traumatic injuries may present with different clinical situations which demand immediate attention and assessment by the clinician. The maxillary central incisor crown fractures are the most common variant of trauma, because of the anterior and protrusive positioning. This case report describes the novel method to produce expansion of the dental arches to correct the post-traumatic displacement of the central incisor along with aesthetic and functional rehabilitation of Ellis Class IV fracture of permanent maxillary central incisor.

  19. Slipping and rolling on an inclined plane

    International Nuclear Information System (INIS)

    Aghamohammadi, Cina; Aghamohammadi, Amir

    2011-01-01

    In the first part of the paper, using a direct calculation two-dimensional motion of a particle sliding on an inclined plane is investigated for general values of friction coefficient (μ). A parametric equation for the trajectory of the particle is also obtained. In the second part of the paper, the motion of a sphere on the inclined plane is studied. It is shown that the evolution equation for the contact point of a sliding sphere is similar to that of a point particle sliding on an inclined plane whose friction coefficient is 7/2 μ. If μ > 2/7 tan θ, for any arbitrary initial velocity and angular velocity, the sphere will roll on the inclined plane after some finite time. In other cases, it will slip on the inclined plane. In the case of rolling, the centre of the sphere moves on a parabola. Finally the velocity and angular velocity of the sphere are exactly computed.

  20. Experimental and theoretical analysis on the effect of inclination on metal powder sintered heat pipe radiator with natural convection cooling

    Science.gov (United States)

    Cong, Li; Qifei, Jian; Wu, Shifeng

    2017-02-01

    An experimental study and theoretical analysis of heat transfer performance of a sintered heat pipe radiator that implemented in a 50 L domestic semiconductor refrigerator have been conducted to examine the effect of inclination angle, combined with a minimum entropy generation analysis. The experiment results suggest that inclination angle has influences on both the evaporator and condenser section, and the performance of the heat pipe radiator is more sensitive to the inclination change in negative inclined than in positive inclined position. When the heat pipe radiator is in negative inclination angle position, large amplitude of variation on the thermal resistance of this heat pipe radiator is observed. As the thermal load is below 58.89 W, the influence of inclination angle on the overall thermal resistance is not that apparent as compared to the other three thermal loads. Thermal resistance of heat pipe radiator decreases by 82.86 % in inclination of 60° at the set of 138.46 W, compared to horizontal position. Based on the analysis results in this paper, in order to achieve a better heat transfer performance of the heat pipe radiator, it is recommended that the heat pipe radiator be mounted in positive inclination angle positions (30°-90°), where the condenser is above the evaporator.

  1. Unusual anatomy of maxillary central incisor with two roots

    Directory of Open Access Journals (Sweden)

    T S Ashwini Shivakumar

    2012-01-01

    Full Text Available Introduction: Knowledge of root canal morphology is essential for successful endodontic therapy. Failure to recognize unusual root canal anatomy may lead to unsuccessful endodontic treatment. Case Report: This case report describes the successful endodontic treatment of the maxillary central incisor with unusual anatomy of two roots and two root canals. A 23-year-old male patient was referred for dental consultation with discoloration of the maxillary right central incisor with periapical lesion, which revealed unusual anatomy of root on radiographic examination, and was confirmed upon exploration. Discussion: As described by Vertucci, the maxillary central incisor presents a single root and single root canal in 100% of the cases. However, few cases of maxillary central incisors with two canals were reported in the literature, most of which were associated with developmental anomalies like fusion, germination or dens invaginatus. Clinician should be aware of the unusual anatomical variations that should be detected by the different diagnostic resources available.

  2. Towards red-edge positions less sensitive to canopy biophysical parameters for leaf chlorophyll estimation using properties optique spectrales des feuilles (PROSPECT) and scattering by arbitrarily inclined leaves (SAILH) simulated data

    NARCIS (Netherlands)

    Cho, M.A.; Skidmore, A.K.; Atzberger, C.

    2008-01-01

    Several methods for extracting the chlorophyll sensitive red-edge position (REP) from hyperspectral data are reported in literature. This study is a continuation of a recent paper published as 'A new technique for extracting the red edge position from hyperspectral data: the linear extrapolation

  3. Prevalence, association, and sexual dimorphism of Carabelli's molar and shovel incisor traits amongst Jordanian population.

    Science.gov (United States)

    Khraisat, A; Taha, Sahar T; Jung, R E; Hattar, S; Smadi, L; Al-Omari, I K; Jarbawi, M

    2007-09-01

    The correlation between dental morphological traits can be used as an indicator to show major ethnic differences. Therefore, this study investigated the prevalence of Carabelli's molar and shovel incisor traits and tested their association and sexual dimorphism in Jordanian population. Three hundred subjects of school children at their 10th grade and of 15.5-year as an average age were involved. Alginate impressions for the maxillary arch were taken, poured, and casts were then trimmed. The selected accurate casts were of 132 male- and 155 female-students. The examined morphologic traits were Carabelli's trait on the maxillary first and second molars and shovel-shaped incisors. The relationship between different traits was investigated by Nonparametric Correlation analysis and Independent Sample t test was used to test sexual dimorphism in trait expression. The prevalence of Carabelli's trait in maxillary first molar and shovel trait in maxillary central incisor was relatively high (65.0 % and 53.0 %, respectively). The prevalence of Carabelli's trait on maxillary second molars was 3.8 %. Nonparametric Correlations revealed a strongest positive correlation between Carabelli's trait on maxillary first molar and shovel trait in males (P = 0.005). Significant sexual dimorphism was only found in the prevalence of Carabelli's trait on maxillary first molar (P = 0.013) and shovel trait (P = 0.038). The Jordanian Population had comparatively high prevalence of Carabelli's molar and shovel incisor traits. There was a positive association between Carabelli's trait on maxillary first molar and shovel trait in males. Sexual dimorphism was evident in Carabelli's trait on maxillary first molar and shovel trait.

  4. Unusual anatomy of maxillary central incisor with two roots

    OpenAIRE

    T S Ashwini Shivakumar; Saleem Makandar; Ajay Kadam

    2012-01-01

    Introduction: Knowledge of root canal morphology is essential for successful endodontic therapy. Failure to recognize unusual root canal anatomy may lead to unsuccessful endodontic treatment. Case Report: This case report describes the successful endodontic treatment of the maxillary central incisor with unusual anatomy of two roots and two root canals. A 23-year-old male patient was referred for dental consultation with discoloration of the maxillary right central incisor with periapical les...

  5. Onset of molar incisor hypomineralization (MIH).

    Science.gov (United States)

    Fagrell, Tobias G; Salmon, Phil; Melin, Lisa; Norén, Jörgen G

    2013-01-01

    The etiological factors and timing of the onset of molar incisor hypomineralization (MIH) are still not clear. The aim of this study was to examine ground radial and sagittal sections from teeth diagnosed with MIH using light microscopy, polarized light microscopy and X-ray micro-computed tomography (XMCT) and to estimate the onset and timing of the MIH and to relate the hypomineralized enamel to the incremental lines. Thirteen extracted permanent first molars diagnosed MIH, were analyzed with light microscopy and XMCT. The hypomineralized areas were mainly located in the mesio-buccal cusps, starting at the enamel-dentin-junction and continuing towards the enamel surface. In a relative gray scale analysis the values decreased from the EDJ towards the enamel surface. The findings indicate that the ameloblasts in the hypomineralized enamel are capable of forming an enamel of normal thickness, but with a substantial reduction of their capacity for maturation of enamel. Chronologically, it is estimated that the timing of the disturbance is at a period during the first 6-7 months of age.

  6. Excavating wide inclines in weak strata

    Energy Technology Data Exchange (ETDEWEB)

    Kuznetsov, N N [Ukrspetsstroiproekt (USSR)

    1990-09-01

    Discusses schemes for excavation of transport inclines in surface mines under conditions of weak, unstable rocks characterized by a high water content. The schemes are aimed at maximum reduction of excavation operations without infringing the safety of personnel. Use of walking draglines (the EhSh-20/90, EhSh-100/100 and EhSh-10/70) is evaluated. Optimum schemes for incline excavation and determining optimum slope inclination are described on the example of the Berezovsk brown coal surface mine in the USSR. Efficiency of optimum schemes is analyzed: range of excavation, safety degree, landslide hazards, water influx rate, accident rate, etc.

  7. Incisor malalignment and the risk of periodontal disease progression.

    Science.gov (United States)

    Alsulaiman, Ahmed A; Kaye, Elizabeth; Jones, Judith; Cabral, Howard; Leone, Cataldo; Will, Leslie; Garcia, Raul

    2018-04-01

    The objective of this study was to investigate the association between incisor crowding, irregularity, and periodontal disease progression in the anterior teeth. Data collected over 35 years from men enrolled in the Veterans Affairs Dental Longitudinal Study included information concerning pocket depth and alveolar bone loss. Plaster casts of the maxillary (n = 400) and mandibular (n = 408) arches were available for baseline measurements. Periodontal disease in the anterior teeth was defined as per arch sum of pathologic pocket depth and sum of teeth with any alveolar bone loss in the anterior sextants. Incisor malalignment status was defined by the anterior tooth size-arch length discrepancy index and Little's Irregularity Index. Adjusted mixed effects linear models computed the beta (β) estimates and 95% confidence intervals (95% CI) of the amounts of change in periodontal disease outcomes by the level of malalignment. In the anterior maxillary arch, crowding and spacing were significantly associated with an increased per-arch sum of pathologic pocket depth (β, 0.70 mm; 95% CI, 0.20-1.21, and β, 0.49 mm; 95% CI, 0.06-0.91, respectively). In the anterior mandibular arch, incisor crowding and irregularity were significantly associated with an increased per-arch sum of pathologic pocket depth (mild crowding: β, 0.47 mm; 95% CI, 0.01-0.93; severe irregularity: β, 0.94 mm; 95% CI, 0.50-1.38), and the sum number of teeth with alveolar bone loss (mild and moderate-to-severe crowding: β, 0.45 teeth; 95% CI, 0.08-0.82; and β, 0.45 teeth; 95% CI, 0.13-0.83, respectively; moderate irregularity: β, 0.34 teeth; 95% CI, 0.06-0.62). Certain incisor malalignment traits (ie, maxillary incisor crowding, maxillary incisor spacing, mandibular incisor mild crowding, mandibular incisor moderate-to-severe crowding, mandibular incisor moderate irregularity, and mandibular incisor severe irregularity) are associated with significant periodontal disease progression

  8. The relationships between the arrangement of teeth, root resorption, and dental maturity in bovine mandibular incisors

    Science.gov (United States)

    An, Jin-kyu; Ono, Takashi

    2017-01-01

    Objective The objective of this study is to investigate the eruption pattern and root resorption of the bovine anterior dentition in relation to growth-related parameters based on dental maturity. Methods A cross-sectional study was conducted on 110 bovine anterior mandibles by using standard radiography, cone-beam computed tomography (CBCT), and actual measurements. We determined the relationships between the stages of dental maturity by using a modification of Demirjian's method and various growth-related parameters, such as the activity of the root-resorbing tissue and mobility of the deciduous teeth. The correlation of growth-related parameters with interdental spacing and distal unusual root resorption (DRR) of the deciduous fourth incisor was assessed. The cause of mesial unusual root resorption (MRR) of the deciduous fourth incisor was determined on the basis of the arrangement of the permanent third incisor. Results An independent t-test and chi-square test indicated significant differences in growth-related parameters associated with dental arch length discrepancy and factors related to the shedding of deciduous teeth between the low and high dental maturity groups. The samples with interdental spacing and DRR showed a larger sum of mesiodistal permanent crown widths and higher dental maturity than did the respective controls. Samples with MRR tended to show a lingually rotated distal tip of the adjacent tooth crown. Conclusions Dental maturity has relevance to the interdental spaces and unusual root resorption of mixed dentition. The position of the adjacent tooth crown on CBCT may be correlated with the occurrence of unusual root resorption of the incisor. PMID:29090124

  9. Families Among High-Inclination Asteroids

    Science.gov (United States)

    Novakovic, B.; Cellino, A.; Knezevic, Z.

    2012-05-01

    We review briefly the most important results of the classification of high-inclination asteroids into families performed by Novakovic et al.(Icarus, 2011,216) and present some new results about a very interesting (5438) Lorre cluster.

  10. Superior glenoid inclination and rotator cuff tears.

    Science.gov (United States)

    Chalmers, Peter N; Beck, Lindsay; Granger, Erin; Henninger, Heath; Tashjian, Robert Z

    2018-03-23

    The objectives of this study were to determine whether glenoid inclination (1) could be measured accurately on magnetic resonance imaging (MRI) using computed tomography (CT) as a gold standard, (2) could be measured reliably on MRI, and (3) whether it differed between patients with rotator cuff tears and age-matched controls without evidence of rotator cuff tears or glenohumeral osteoarthritis. In this comparative retrospective radiographic study, we measured glenoid inclination on T1 coronal MRI corrected into the plane of the scapula. We determined accuracy by comparison with CT and inter-rater reliability. We compared glenoid inclination between patients with full-thickness rotator cuff tears and patients aged >50 years without evidence of a rotator cuff tear or glenohumeral arthritis. An a priori power analysis determined adequate power to detect a 2° difference in glenoid inclination. (1) In a validation cohort of 37 patients with MRI and CT, the intraclass correlation coefficient was 0.877, with a mean difference of 0° (95% confidence interval, -1° to 1°). (2) For MRI inclination, the inter-rater intraclass correlation coefficient was 0.911. (3) Superior glenoid inclination was 2° higher (range, 1°-4°, P rotator cuff tear group of 192 patients than in the control cohort of 107 patients. Glenoid inclination can be accurately and reliably measured on MRI. Although superior glenoid inclination is statistically greater in those with rotator cuff tears than in patients of similar age without rotator cuff tears or glenohumeral arthritis, the difference is likely below clinical significance. Copyright © 2018 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

  11. Entrepreneurial inclinations of women from rural areas

    Directory of Open Access Journals (Sweden)

    Marković-Savić Olivera S.

    2014-01-01

    Full Text Available Entrepreneurial inclinations of women from rural areas are shaped by the lack of business ideas and economic capital, which, in addition to financial resources, includes cultural capital in the form of knowledge and skills. The paper presents a part of a broader study on the social position of women from the rural areas of northern Kosovo and Metohija, conducted in 2013. The research was predominantly focused on entrepreneurial inclinations of rural women, and the findings suggest that private enterprise in the studied population is undeveloped as a result of two dominant reasons. The first reason is the situation which is unfavorable in terms of politics and security, and therefore, not conducive to investment security, together with the specificity in the form of complex administrative business conditions requiring compliance to parallel and mutually incompatible standards (of the Republic of Serbia and of the UNMIK administration. The second important reason for the lack of entrepreneurial initiatives is the lack of ownership of property and the means of production, since banks do not give loans without guarantees in the form of ownership of the mortgage, while other forms of financial incentives are unavailable. The respondents attended programs for acquiring new knowledge and skills only in a small number of cases, while showing the greatest susceptibility to education in traditional skills, such as training in agriculture and handicrafts, which are not the skills in line with the needs of the labor market. As the most important reasons that -prevent them from having their own business, the respondents -mentioned: the lack of ideas and the lack of financial resources. In this regard, they would find incentives in the form of grants most helpful to start their own business. The absence of funds and gender inequality form the basis for the lack of ownership of property and means of production. In addition to the shortage of financial

  12. Agenesis of maxillary lateral incisors and associated dental anomalies.

    Science.gov (United States)

    Garib, Daniela Gamba; Alencar, Bárbara Maria; Lauris, José Roberto Pereira; Baccetti, Tiziano

    2010-06-01

    The objectives of this study were to evaluate the prevalence of dental anomalies in patients with agenesis of maxillary lateral incisors and to compare the findings with the prevalence of these anomalies in the general population. A sample of 126 patients, aged 7 to 35 years, with agenesis of at least 1 maxillary lateral incisor was selected. Panoramic and periapical radiographs and dental casts were used to analyze other associated dental anomalies, including agenesis of other permanent teeth, ectopia of unerupted permanent teeth, microdontia of maxillary lateral incisors, and supernumerary teeth. The occurrence of these anomalies was compared with prevalence data previously reported for the general population. Statistical testing was performed with the chi-square test (P <0.05) and the odds ratio. Patients with maxillary lateral incisor agenesis had a significantly increased prevalence rate of permanent tooth agenesis (18.2%), excluding the third molars. The occurrence of third-molar agenesis in a subgroup aged 14 years or older (n = 76) was 35.5%. The frequencies of maxillary second premolar agenesis (10.3%), mandibular second premolar agenesis (7.9%), microdontia of maxillary lateral incisors (38.8%), and distoangulation of mandibular second premolars (3.9%) were significantly increased in our sample compared with the general population. In a subgroup of patients aged 10 years or older (n = 115), the prevalence of palatally displaced canines was elevated (5.2%). The prevalences of mesioangulation of mandibular second molars and supernumerary teeth were not higher in the sample. Permanent tooth agenesis, maxillary lateral incisor microdontia, palatally displaced canines, and distoangulation of mandibular second premolars are frequently associated with maxillary lateral incisor agenesis, providing additional evidence of a genetic interrelationship in the causes of these dental anomalies. 2010 American Association of Orthodontists. Published by Mosby, Inc. All

  13. Relationship between the shape of the upper central incisors and the facial contour in dental students. Lima. Peru.

    Directory of Open Access Journals (Sweden)

    Miguel Cabello

    2015-06-01

    Full Text Available Determine the relationship between the shape of the face and the shape of the upper right central incisor according to “The law of harmony” proposed by Williams. Materials and methods: This was an observational, analytic and cross-sectional study. A sample of 124 subjects, male and female students between 17 and 28 years old, was selected for the research. Their facial biotype and the shape of their upper right central incisor were determined by means of direct and photographic methods. Height and facial width were clinically evaluated using the direct method, and the proximal contours of the incisors were evaluated using a Vernier digital caliper. Images were downloaded to a computer and analyzed by means of the photographic method using Adobe Photoshop 5.0. Results: The relationship between the shape of the face and the shape of the incisor was positive in 43.5% of the sample (p=0.006 in the direct method. In the photographic method, the relationship between the shape of the face and the shape of the incisor was positive in 41.1% of the sample (p=0.037. The most frequent facial biotype in the direct and photographic methods was the dolichofacial with 61.3% and 71% respectively. The most frequent shape of the tooth with the direct and photographic methods was the ovoid with 55.6% and 51.6% respectively. Conclusion: Results do not confirm “The law of harmony” proposed by Williams, therefore when choosing the most suitable anterior tooth, experience and criteria of the dentist as well as the opinion of the patient should be taken in account in order to achieve a good aesthetic result.

  14. Management of unerupted maxillary deciduous central incisor: a case report.

    Science.gov (United States)

    Shakra, Karam Abu

    2014-01-01

    Failure of eruption of primary teeth can be considered rare, especially in maxillary anterior teeth. The problem can be either mechanical obstruction of eruption or a failure of the eruption mechanism. This case report presents failure of eruption of the maxillary right deciduous central incisor in a 4-year-old girl. The unerupted primary tooth was removed surgically. The histological finding revealed fibroma with reactive giant cells. Periodic follow-up visits were advised to monitor the developing dentition and to ensure enough space for the permanent incisor. How to cite this article: Shakra KA. Management of Unerupted Maxillary Deciduous Central Incisor: A Case Report. Int J Clin Pediatr Dent 2014;7(1):58-60.

  15. Orthodontic management of impacted central incisor: A clinical challenge

    Directory of Open Access Journals (Sweden)

    Amit Kumar Khera

    2017-01-01

    Full Text Available Multiple treatment options are available for patients who have impacted incisor. This paper shows a case in which orthodontic as well as surgical considerations in 10-year-old female child were presented in the management of impacted central incisor. The orthodontic treatment plan included three steps – creation of space, exposure of crown, and forced eruption. A unique and innovative technique for orthodontic traction (0.017 × 0.025 TMA wire with palatal extension was employed to move the maxillary incisor into arch, with minimum injury to neighboring soft tissue. After the successful management of impacted teeth, it is very important to periodically review the periodontal condition and stability.

  16. Locomotor Behavior of Chickens Anticipating Incline Walking

    Directory of Open Access Journals (Sweden)

    Chantal LeBlanc

    2018-01-01

    Full Text Available Keel bone damage (KBD is prevalent in hens raised for egg production, and ramps between different tiers in aviaries have potential to reduce the frequency of falls resulting in KBD. Effective use of ramps requires modulation of locomotion in anticipation of the incline. Inadequate adaptive locomotion may be one explanation why domestic layer hens (Gallus gallus domesticus exhibit high rates of KBD. To improve understanding of the capacity of hens to modulate their locomotion in anticipation of climbing, we measured the effects of incline angle upon the mechanics of the preparatory step before ascending a ramp. Because the energetic challenge of climbing increases with slope, we predicted that as angle of incline increased, birds during foot contact with the ground before starting to climb would increase their peak force and duration of contact and reduce variation in center of pressure (COP under their foot. We tested 20 female domestic chickens on ramp inclines at slopes of +0°, +40°, and +70° when birds were 17, 21, 26, 31, and 36 weeks of age. There were significantly higher vertical peak ground reaction forces in preparation at the steepest slope, and ground contact time increased significantly with each increase in ramp angle. Effects upon variation in COP were not apparent; likewise, effects of limb length, age, body mass were not significant. Our results reveal that domestic chickens are capable of modulating their locomotion in response to incline angle.

  17. Ring formation on an inclined surface

    Science.gov (United States)

    Deegan, Robert; Du, Xiyu

    2015-11-01

    A drop dried on a solid surface will typically leave a narrow band of solute deposited along the contact line. We examined variations of this deposit due to the inclination of the substrate using numerical simulations of a two-dimensional drop, equivalent to a strip-like drop. An asymptotic analysis of the contact line region predicts that the upslope deposit will grow faster at early times, but the growth of this deposit ends sooner because the upper contact line depins first. From our simulations we find that the deposit can be larger at either the upper or lower contact line depending on the initial drop volume and substrate inclination. For larger drops and steeper inclinations, the early lead in deposited mass at the upper contact line is wiped out by the earlier depinning of the upper contact line and subsequent continued growth at the lower contact line. Conversely, for smaller drops and shallower inclinations, the early lead of the upper contact line is insurmountable despite its earlier termination in growth. Our results show that it is difficult to reconstruct a postiorithe inclination of the substrate based solely on the shape of the deposit. The authors thank the James S. McDonnell Foundation for support through a 21st Century Science Initiative in Studying Complex Systems Research Award, and the National Science Foundation for support under Grant No. 0932600.

  18. Multidisciplinary treatment of a fractured maxillary central incisor

    Directory of Open Access Journals (Sweden)

    Praveen Kumar Neela

    2017-01-01

    Full Text Available Subgingivally fractured incisors are still a challenge to treat. Restoration of severely damaged teeth requires careful attention and comprehensive preplanned treatment. Here, a patient who had traumatic injury to the upper left central incisor which led to an oblique fracture involving enamel, dental and extending into the root below the gingival margin was saved from extraction by accelerated forced eruption of a root portion, allowing placement of crown, and eliminating the need for a fixed partial denture. A tooth otherwise would have gone for extraction routinely was thus saved and restored through a multidisciplinary approach by a combined orthodontic, periodontal and endodontic treatment.

  19. How much incisor decompensation is achieved prior to orthognathic surgery?

    Science.gov (United States)

    McNeil, Calum; McIntyre, Grant T; Laverick, Sean

    2014-07-01

    To quantify incisor decompensation in preparation for orthognathic surgery. Pre-treatment and pre-surgery lateral cephalograms for 86 patients who had combined orthodontic and orthognathic treatment were digitised using OPAL 2.1 [http://www.opalimage.co.uk]. To assess intra-observer reproducibility, 25 images were re-digitised one month later. Random and systematic error were assessed using the Dahlberg formula and a two-sample t-test, respectively. Differences in the proportions of cases where the maxillary (1100 +/- 60) or mandibular (900 +/- 60) incisors were fully decomensated were assessed using a Chi-square test (ppre-surgical orthodontics, surgical-orthodontic.

  20. Bilateral fusion of permanent mandibular incisors: A case report

    Directory of Open Access Journals (Sweden)

    Saxena A

    2008-05-01

    Full Text Available This case report showing a classical presentation of bilateral fusion of permanent mandibular incisors in a child patient for dental attention. Fusion defined as the merger of two adjacent tooth germs producing one tooth. These teeth may be fused by enamel, dentin, or both. The fused crown is broader than non fused adjacent teeth and thus resembles gemination. However, tooth counting reveals decreased numbers. Fused teeth are rare in the permanent dentition. The incisors are reported to be fused in primary and permanent dentition, but bilateral fusion is a rare occurrence. Hence the case report of bilateral fusion in an 11-year-old boy is presented.

  1. Three-dimensional volumetric display by inclined-plane scanning

    Science.gov (United States)

    Miyazaki, Daisuke; Eto, Takuma; Nishimura, Yasuhiro; Matsushita, Kenji

    2003-05-01

    A volumetric display system based on three-dimensional (3-D) scanning that uses an inclined two-dimensional (2-D) image is described. In the volumetric display system a 2-D display unit is placed obliquely in an imaging system into which a rotating mirror is inserted. When the mirror is rotated, the inclined 2-D image is moved laterally. A locus of the moving image can be observed by persistence of vision as a result of the high-speed rotation of the mirror. Inclined cross-sectional images of an object are displayed on the display unit in accordance with the position of the image plane to observe a 3-D image of the object by persistence of vision. Three-dimensional images formed by this display system satisfy all the criteria for stereoscopic vision. We constructed the volumetric display systems using a galvanometer mirror and a vector-scan display unit. In addition, we constructed a real-time 3-D measurement system based on a light section method. Measured 3-D images can be reconstructed in the 3-D display system in real time.

  2. Measurement of the buccolingual inclination of teeth: manual technique vs 3-dimensional software.

    Science.gov (United States)

    Nouri, Mahtab; Abdi, Amir Hossein; Farzan, Arash; Mokhtarpour, Faraneh; Baghban, AliReza Akbarzadeh

    2014-10-01

    In this study, we aimed to measure the inclination of teeth on dental casts by a manual technique with the tooth inclination protractor (TIP; MBI, Newport, United Kingdom) and a newly designed 3-dimensional (3D) software program. The correlation of the 2 techniques was evaluated, and the reliability of each technique was assessed separately. This study was conducted on 36 dental casts of normal, well-aligned Class I occlusions; we assessed 432 teeth. All casts had a normal Class I occlusion. After determining the facial axis of the clinical crown and the facial axis points on the dental casts, we measured the inclinations of the incisors and posterior teeth up to the first molars in each dental arch relative to Andrews' occlusal plane and the posterior occlusal plane using the TIP. Moreover, the casts were scanned by a structured-light 3D scanner. The inclination of teeth relative to the occlusal plane was determined using the new software. To assess the reliability, measurements of all teeth from 15 casts were repeated twice by the 2 methods. Intraclass correlation coefficient and Dahlberg's formula were used for calculation of correlation and reliability. Overall, the 2 techniques were not significantly different in the measurements of the inclinations of the teeth in both jaws. The ranges of Dahlberg's formula were 3.1° to 5.8° for the maxilla and 3.3° to 5.9° for the mandible. The overall correlation of the 2 techniques according to the intraclass correlation coefficient was 0.91. For calculation of reliability, the intraclass correlation coefficients for the TIP and the 3D method were 0.73 and 0.82, respectively. The TIP and the 3D software showed a high correlation for measurement of the inclinations of maxillary and mandibular teeth relative to the occlusal plane. Also, the reproducibility of the measurements in each method was high. Copyright © 2014 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

  3. Inclined nanoimprinting lithography for 3D nanopatterning

    International Nuclear Information System (INIS)

    Liu Zhan; Bucknall, David G; Allen, Mark G

    2011-01-01

    We report a non-conventional shear-force-driven nanofabrication approach, inclined nanoimprint lithography (INIL), for producing 3D nanostructures of varying heights on planar substrates in a single imprinting step. Such 3D nanostructures are fabricated by exploiting polymer anisotropic dewetting where the degree of anisotropy can be controlled by the magnitude of the inclination angle. The feature size is reduced from micron scale of the template to a resultant nanoscale pattern. The underlying INIL mechanism is investigated both experimentally and theoretically. The results indicate that the shear force generated at a non-zero inclination angle induced by the INIL apparatus essentially leads to asymmetry in the polymer flow direction ultimately resulting in 3D nanopatterns with different heights. INIL removes the requirements in conventional nanolithography of either utilizing 3D templates or using multiple lithographic steps. This technique enables various 3D nanoscale devices including angle-resolved photonic and plasmonic crystals to be fabricated.

  4. The influence of incline walking on joint mechanics.

    Science.gov (United States)

    Haggerty, Mason; Dickin, D Clark; Popp, Jennifer; Wang, Henry

    2014-04-01

    Walking is a popular form of exercise and is associated with many health benefits; however, frontal-plane knee joint loading brought about by a large internal knee-abduction moment and cyclic loading could lead to cartilage degeneration over time. Therefore, knee joint mechanics during an alternative walking exercise needs to be analyzed. The purpose of this study was to examine the lower-extremity joint mechanics in the frontal and sagittal planes during incline walking. Fifteen healthy males walked on a treadmill at five gradients (0%, 5%, 10%, 15%, and 20%) at 1.34m/s, and lower-extremity joint mechanics in the frontal and sagittal planes were quantified. The peak internal knee-abduction moment significantly decreased from the level walking condition at all gradients except 5%. Also, a negative relationship between the internal knee-abduction moment and the treadmill gradient was found to exist in 10% increments (0-10%, 5-15%, and 10-20%). The decrease in the internal knee-abduction moment during incline walking could have positive effects on knee joint health such as potentially reducing cartilage degeneration of the knee joint, reducing pain, and decreasing the rate of development of medial tibiofemoral osteoarthritis. This would be beneficial for a knee surgery patient, obese persons, and older adults who are using incline walking for rehabilitation and exercise protocols. Findings from the current study can provide guidance for the development of rehabilitation and exercise prescriptions incorporating incline walking. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. A new approach to incisor retention--the lingual spur retainer.

    LENUS (Irish Health Repository)

    McNamara, T G

    1996-08-01

    Late lower incisor crowding and incisor rotations remain a problem in orthodontics. We describe a new fixed retainer which is simple to use, allows physiological tooth movement, but prevents rotational and labio-lingual relapse.

  6. Ectopic eruption of maxillary central incisor through abnormally thickened labial frenum: An unusual presentation

    Directory of Open Access Journals (Sweden)

    Neeraj Gugnani

    2017-01-01

    Full Text Available Ectopic eruption is a deviation from the normal eruption pattern, making the tooth erupt out of its normal position, and possibly causing resorption of adjacent primary teeth. A wide range of etiological factors may be responsible for ectopic eruption of the teeth, so their management depends on the correction of the established etiological factor. The present case report describes an unusual case of ectopically erupted central incisor encased within an abnormally thickened labial frenum, which was treated by orthodontic repositioning of the ectopically erupting tooth after frenectomy.

  7. Immunocytochemical localization of claudin 1 in the maturation ameloblasts of rat incisors

    Directory of Open Access Journals (Sweden)

    Sumio eNishikawa

    2010-11-01

    Full Text Available Claudin 1 is a tight junction transmembrane protein. Its localization in the maturation ameloblasts of rat incisors was examined by immunofluorescence microscopy. Distal junction area of ruffle-ended ameloblasts (RA and the Golgi apparatus of a sub-population of smooth-ended ameloblasts (SA and RAs stained positive with anti-claudin 1 antibodies. Since it has been shown that ameloblasts repeatedly alternate between an SA and an RA morphology during enamel maturation, the presence of claudin 1 in the Golgi cisterns may indicate the presence of tight junction precursors before transportation to the junctional area.

  8. Breakwaters with Vertical and Inclined Concrete Walls

    DEFF Research Database (Denmark)

    Burcharth, Hans Falk

    Following the PIANC PTC II working group on Analyses of Rubble Mound Breakwaters it was, in 1991, decided to form Working Group (WG) n° 28 on "Breakwaters with vertical and inclined concrete walls" The scope of the work was to achieve a better understanding of the overall safety aspects in the de......Following the PIANC PTC II working group on Analyses of Rubble Mound Breakwaters it was, in 1991, decided to form Working Group (WG) n° 28 on "Breakwaters with vertical and inclined concrete walls" The scope of the work was to achieve a better understanding of the overall safety aspects...

  9. The Bearing Capacity of Strip Footings in Cohesionless Soil Subject to Eccentric and Inclined Loads

    DEFF Research Database (Denmark)

    Krabbenhøft, Sven; Damkilde, Lars; Krabbenhøft, Kristian

    2014-01-01

    Lower bound calculations based on the finite element method is used to determine the bearing capacity of a strip foundation subjected to an inclined, eccentric load on cohesionless soil with varying surcharges and with friction angles 25, 30 and 35°. The soil is assumed perfectly plastic following...... the Mohr-Coulomb failure criterion. The results are reported as graphs showing the bearing capacity as a function of the friction angle, the eccentricity, inclination and the surcharge. The results have been compared with the Eurocode 7 and for smaller eccentricities, except in the case of no surcharge......, the lower bound values are the greater, the discrepancy increasing with growing surcharge. Positive load inclinations has a negative effect for smaller eccentricities but may have a beneficial effect on the bearing capacity for greater eccentricities. Negative load inclinations have the opposite effect...

  10. Shovel-shaped incisors in the Black Sea region population of Turkey

    Directory of Open Access Journals (Sweden)

    Emin Murat Canger

    2014-09-01

    Conclusion: The incidence of shovel-shaped incisors was 10.1% in our study group; SSI affected lateral incisors more than central incisors; the number of women reflecting SSI was higher than men; and the majority of individuals had Type II (semi-shovel severity.

  11. Effect of clear aligner therapy on the buccolingual inclination of mandibular canines and the intercanine distance.

    Science.gov (United States)

    Grünheid, Thorsten; Gaalaas, Sara; Hamdan, Hani; Larson, Brent E

    2016-01-01

    To compare the changes in buccolinugal inclination of mandibular canines and intercanine distance in patients treated with clear aligners to those treated with preadjusted edgewise appliances. The buccolingual inclination of mandibular canines and the intercanine distance were measured on pre- and posttreatment cone-beam computed tomograms of 30 patients who had been treated with clear aligners and 30 patients who had been treated with fixed preadjusted edgewise appliances. Differences between the aligner and fixed appliance groups and between pre- and posttreatment measurements were tested for statistical significance. In both groups, most of the mandibular canines had positive buccolingual inclinations (ie, their crowns were positioned lateral to their roots) both before and after treatment. While there was no difference between the groups pretreatment, the posttreatment buccolingual inclination was significantly greater in the aligner group. In the fixed appliance group, the canines became more upright with treatment, while the buccolingual inclination did not change significantly in the clear aligner group. The intercanine distance did not differ between the groups either before or after treatment. However, it increased significantly over the course of treatment in the aligner group, whereas it did not change significantly in the fixed appliance group. Orthodontic treatment with clear aligners tends to increase the mandibular intercanine distance with little change in inclination in contrast to treatment with fixed appliances, which leaves the intercanine distance unchanged but leads to more upright mandibular canines.

  12. Elastic Band Causing Exfoliation of the Upper Permanent Central Incisors

    Directory of Open Access Journals (Sweden)

    Monica Ghislaine Oliveira Alves

    2015-01-01

    Full Text Available Objective. This study reports a case in which elastic band use culminated in the loss of the incisors. Case Report. An 11-year-old white girl was seen complaining of pain, with purulent discharge and severe tooth mobility. The bone destruction detected radiographically in the region, despite its single location and absence in posterior quadrants of the maxilla and/or mandible, was similar to that observed in Langerhans cell disease. To our surprise, an elastic band involving the midportion of the roots of the two upper central incisors was found during biopsy. The debris was removed and a metal wire was placed in permanent maxillary right and left incisors. The patient was followed up, but no improvement in tooth mobility was observed. Bone loss increased, and internal resorption and root exposure occurred, which culminated in the extraction of permanent maxillary right and left incisors. Conclusion. The present case highlights the fact that professionals sometimes are confronted by anamnestic reports never seen before.

  13. Vehicle with inclinable caterpillar propulsion units

    International Nuclear Information System (INIS)

    Clar, G.

    1991-01-01

    This vehicle usable in hostile environment such nuclear industry has four propulsion units with a caterpillar track and two integrated motors: one for advancing the caterpillar track and the other for inclining the propulsion unit when overcoming obstacles. Each propulsion unit is easily replaceable because there are no mechanical parts in the body of the vehicle [fr

  14. Internally cooled V-shape inclined monochromator

    Czech Academy of Sciences Publication Activity Database

    Oberta, Peter; Áč, V.; Hrdý, Jaromír

    2008-01-01

    Roč. 15, - (2008), 8-11 ISSN 0909-0495 R&D Projects: GA AV ČR IAA100100716 Grant - others:VEGA(SK) 1/4134/07 Institutional research plan: CEZ:AV0Z10100522 Keywords : inclined monochromator * heat load * internal cooling Subject RIV: BH - Optics, Masers, Lasers Impact factor: 2.333, year: 2008

  15. Managing molar-incisor hypomineralization: A systematic review.

    Science.gov (United States)

    Elhennawy, Karim; Schwendicke, Falk

    2016-12-01

    We systematically reviewed treatment modalities for MIH-affected molars and incisors. Trials on humans with ≥1 MIH molar/incisor reporting on various treatments were included. Two authors independently searched and extracted records. Sample-size-weighted annual failure rates were estimated where appropriate. The risk of bias was assessed using the Newcastle-Ottawa scale. Electronic databases (PubMed, Embase, Cochrane CENTRAL, Google Scholar) were screened, and hand searches and cross-referencing performed. Fourteen (mainly observational) studies were included. Ten trials (381 participants) investigated MIH-molars, four (139) MIH-incisors. For molars, remineralization, restorative or extraction therapies had been assessed. For restorative approaches, mean (SD) annual failure rates were highest for fissure sealants (12[6]%) and glass-ionomer restorations (12[2]%), and lowest for indirect restorations (1[3]%), preformed metal crowns (1.3 [2.1]%) and composite restorations (4[3]%). Ony study assessed extraction of molars in young patients (median age 8.2 years), the majority of them without malocclusions, but third molars in development. Spontaneous alignment of second molars was more frequent in the maxilla (55%) than the mandible (47%). For incisors, desensitizing agents successfully managed hypersensitivity. Micro-abrasion and composite veneers improved aesthetics. Few, mainly moderate to high-risk-studies investigated treatment of MIH. Remineralization or sealants seem suitable for MIH-molars with limited severity and/or hypersensitivity. For severe cases, restorations with composites or indirect restorations or preformed metal crowns seem suitable. Prior to tooth extraction as last resort factors like the presence of a general malocclusion, patients' age and the status of neighboring teeth should be considered. No recommendations can be given for MIH-incisors. Dentists need to consider the specific condition of each tooth and the needs and expectations of

  16. Executive Function as a Risk Factor for Incisor Trauma.

    Science.gov (United States)

    Nyquist, Jillian M; Phillips, Ceib; Stein, Margot; Koroluk, Lorne D

    2018-05-08

    Executive function is the ability to guide behavior to achieve goals or complete tasks. This study explored the relationship between executive function, as assessed by the Behavior Rating Inventory of Executive Function Parent Form Questionnaire (BRIEF ® ) and incisor trauma. This study included children in the mixed dentition with recent incisor trauma (n=28) and a control group (n=30) without recent incisor trauma. Subjects' parents completed the BRIEF ® , while a clinical examination assessed subjects' occlusal relationships. Parents also completed a custom questionnaire that investigated their child's medical history and daily activities. Fisher Exact and unpaired t-tests compared BRIEF ® scores, occlusal characteristics, medical history, and reported daily activities of the two groups. The trauma group had a greater percentage of participants with a Class II dental relationship (p=0.01). There was no significant difference between groups with respect to mean BRIEF ® t-scores within the Global Executive Composite. There was a statistically significant difference between groups with respect to the percentage of subjects with clinically significant (≥65) BRIEF ® t-scores within the Inhibit (p=0.05) and Emotional Control (p=0.02) subscales and Behavioral Regulation Index (p=0.02). There were no statistically significant differences between groups with respect to age, gender, overbite, overjet, medical history, body mass index, or daily activities. Children in the mixed dentition with a Class II dental relationship are at greater risk for incisor injury, as well as those involved in outdoor activities. Specific executive dysfunctions such as impulsivity and poor emotional control may increase the risk for incisor trauma. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  17. Radiologically determined orthodontically induced external apical root resorption in incisors after non-surgical orthodontic treatment of class II division 1 malocclusion: a systematic review.

    Science.gov (United States)

    Tieu, Long D; Saltaji, Humam; Normando, David; Flores-Mir, Carlos

    2014-07-23

    This study aims to critically evaluate orthodontically induced external apical root resorption (OIEARR) in incisors of patients undergoing non-surgical orthodontic treatment of class II division 1 malocclusion by a systematic review of the published data. An electronic search of two databases was performed; the bibliographies of relevant articles were also reviewed. Studies were included if they examined the amount of OIEARR in incisors produced during non-surgical orthodontic treatment of individuals with class II division I malocclusion in the permanent dentition. Individuals had no previous history of OIEARR, syndromes, pathologies, or general diseases. Study selections, risk of bias assessment, and data extraction were performed in duplicate. Eight studies of moderate methodological quality were finally included. An increased prevalence (65.6% to 98.1%) and mild to moderate severity of OIEARR (root) were reported. No sex difference in root resorption was found. For the maxillary incisors, there was no evidence that either the central or lateral incisor was more susceptible to OIEARR. A weak to moderate positive correlation between treatment duration and root resorption, and anteroposterior apical displacement and root resorption was found. Current limited evidence suggests that non-surgical comprehensive orthodontic treatment to correct class II division 1 malocclusions causes increased prevalence and severity of OIEARR the more the incisor roots are displaced and the longer this movement takes.

  18. Orthodontic treatment of severe anterior open bite and alveolar bone defect complicated by an ankylosed maxillary central incisor: a case report.

    Science.gov (United States)

    Lin, Feiou; Sun, Hao; Yao, Linjie; Chen, Qiushuo; Ni, Zhenyu

    2014-11-21

    Incisor trauma is common in children, and can cause severe complications during adolescent growth and development. This report describes the treatment of a 16-year-old patient with severe anterior open bite due to ankylosis of the maxillary left incisor after dental trauma as an 8-year-old. No examination or active treatment was undertaken until he was 16 years old. Clinical examination revealed that the maxillary left incisor was severely intruded accompanied by a vertical alveolar bone defect. Orthodontic treatment combined with surgical luxation took 3 years and 7 months. During treatment, the intruded incisor was moved to the occlusal level and the alveolar bone defect was restored, achieving normal occlusion. After two years of retention, the maxillary left incisor was retained in a stable normal position with a slightly reduced overbite. This case demonstrates that surgical luxation with orthodontic traction can be an effective approach, especially when the ankylosed tooth has a single root. Long-term monitoring of orthodontic stability and the maintenance of periodontal health are crucial in the post-treatment period.

  19. Radiographic studies on the development of incisors and canine teeth in donkeys

    International Nuclear Information System (INIS)

    Misk, N.A.; Semieka, M.M.A.

    1997-01-01

    The aim of the present work is to study the time of radiographic appearance in donkeys of different stages of development of deciduous incisors, permanent incisors and canine teeth; the radiographic length of deciduous incisors, permanent incisors and canines; the process of root resorption of deciduous incisors; and the appearance of the pulp cavity and ifs relation to denial Infundibulum at different ages. Sixty specimens were used and all were radiographed. Interpretation was stated for each, from 1 day up to 17 years of age

  20. The Dance of Tusks: Rediscovery of Lower Incisors in the Pan-American Proboscidean Cuvieronius hyodon Revises Incisor Evolution in Elephantimorpha

    Science.gov (United States)

    2016-01-01

    The incisors of proboscideans (tusks and tushes) are one of the most important feature in conservation, ecology and evolutionary history of these mammals. Although the absence of upper incisors is rare in proboscideans (occurring only in deinotheres), the independent losses of lower incisors are recognized for most of its lineages (dibelodont condition). The presence of lower incisors in the Pan-American gomphothere Cuvieronius hyodon was reported a few times in literature, but it was neglected in systematic studies. We analyzed several specimens of Cuvieronius hyodon from the Americas and recognized that immature individuals had lower incisors during very early post-natal developmental stages. Subsequently, these are lost and lower incisors alveoli close during later developmental stages, before maturity. Moreover, for the first time in a formal cladistic analysis of non-amebelodontine trilophodont gomphotheres, Rhynchotherium and Cuvieronius were recovered as sister-taxa. Among several non-ambiguous synapomorphies, the presence of lower incisors diagnoses this clade. We recognize that the presence of lower incisors in Cuvieronius and Rhynchotherium is an unique case of taxic atavism among the Elephantimorpha, since these structures are lost at the origin of the ingroup. The rediscovery of the lower incisors in Cuvieronius hyodon, their ontogenetic interpretation and the inclusion of this feature in a revised phylogenetic analysis of trilophodont gomphotheres brought a better understanding for the evolutionary history of these proboscideans. PMID:26756209

  1. The Dance of Tusks: Rediscovery of Lower Incisors in the Pan-American Proboscidean Cuvieronius hyodon Revises Incisor Evolution in Elephantimorpha.

    Directory of Open Access Journals (Sweden)

    Dimila Mothé

    Full Text Available The incisors of proboscideans (tusks and tushes are one of the most important feature in conservation, ecology and evolutionary history of these mammals. Although the absence of upper incisors is rare in proboscideans (occurring only in deinotheres, the independent losses of lower incisors are recognized for most of its lineages (dibelodont condition. The presence of lower incisors in the Pan-American gomphothere Cuvieronius hyodon was reported a few times in literature, but it was neglected in systematic studies. We analyzed several specimens of Cuvieronius hyodon from the Americas and recognized that immature individuals had lower incisors during very early post-natal developmental stages. Subsequently, these are lost and lower incisors alveoli close during later developmental stages, before maturity. Moreover, for the first time in a formal cladistic analysis of non-amebelodontine trilophodont gomphotheres, Rhynchotherium and Cuvieronius were recovered as sister-taxa. Among several non-ambiguous synapomorphies, the presence of lower incisors diagnoses this clade. We recognize that the presence of lower incisors in Cuvieronius and Rhynchotherium is an unique case of taxic atavism among the Elephantimorpha, since these structures are lost at the origin of the ingroup. The rediscovery of the lower incisors in Cuvieronius hyodon, their ontogenetic interpretation and the inclusion of this feature in a revised phylogenetic analysis of trilophodont gomphotheres brought a better understanding for the evolutionary history of these proboscideans.

  2. The Dance of Tusks: Rediscovery of Lower Incisors in the Pan-American Proboscidean Cuvieronius hyodon Revises Incisor Evolution in Elephantimorpha.

    Science.gov (United States)

    Mothé, Dimila; Ferretti, Marco P; Avilla, Leonardo S

    2016-01-01

    The incisors of proboscideans (tusks and tushes) are one of the most important feature in conservation, ecology and evolutionary history of these mammals. Although the absence of upper incisors is rare in proboscideans (occurring only in deinotheres), the independent losses of lower incisors are recognized for most of its lineages (dibelodont condition). The presence of lower incisors in the Pan-American gomphothere Cuvieronius hyodon was reported a few times in literature, but it was neglected in systematic studies. We analyzed several specimens of Cuvieronius hyodon from the Americas and recognized that immature individuals had lower incisors during very early post-natal developmental stages. Subsequently, these are lost and lower incisors alveoli close during later developmental stages, before maturity. Moreover, for the first time in a formal cladistic analysis of non-amebelodontine trilophodont gomphotheres, Rhynchotherium and Cuvieronius were recovered as sister-taxa. Among several non-ambiguous synapomorphies, the presence of lower incisors diagnoses this clade. We recognize that the presence of lower incisors in Cuvieronius and Rhynchotherium is an unique case of taxic atavism among the Elephantimorpha, since these structures are lost at the origin of the ingroup. The rediscovery of the lower incisors in Cuvieronius hyodon, their ontogenetic interpretation and the inclusion of this feature in a revised phylogenetic analysis of trilophodont gomphotheres brought a better understanding for the evolutionary history of these proboscideans.

  3. Active Thrust on an Inclined Retaining Wall with Inclined Cohesionless Backfill due to Surcharge Effect

    OpenAIRE

    Dewaikar, D. M.; Pandey, S. R.; Dixit, Jagabandhu

    2012-01-01

    A method based on the application of Kötter’s equation is proposed for the complete analysis of active thrust on an inclined wall with inclined cohesionless backfill under surcharge effect. Coulomb’s failure mechanism is considered in the analysis. The point of application of active thrust is determined from the condition of moment equilibrium. The coefficient of active pressure and the point of application of the active thrust are computed and presented in nondimensional form. One distinguis...

  4. Joint torques and joint reaction forces during squatting with a forward or backward inclined Smith machine.

    Science.gov (United States)

    Biscarini, Andrea; Botti, Fabio M; Pettorossi, Vito E

    2013-02-01

    We developed a biomechanical model to determine the joint torques and loadings during squatting with a backward/forward-inclined Smith machine. The Smith squat allows a large variety of body positioning (trunk tilt, foot placement, combinations of joint angles) and easy control of weight distribution between forefoot and heel. These distinctive aspects of the exercise can be managed concurrently with the equipment inclination selected to unload specific joint structures while activating specific muscle groups. A backward (forward) equipment inclination decreases (increases) knee torque, and compressive tibiofemoral and patellofemoral forces, while enhances (depresses) hip and lumbosacral torques. For small knee flexion angles, the strain-force on the posterior cruciate ligament increases (decreases) with a backward (forward) equipment inclination, whereas for large knee flexion angles, this behavior is reversed. In the 0 to 60 degree range of knee flexion angles, loads on both cruciate ligaments may be simultaneously suppressed by a 30 degree backward equipment inclination and selecting, for each value of the knee angle, specific pairs of ankle and hip angles. The anterior cruciate ligament is safely maintained unloaded by squatting with backward equipment inclination and uniform/forward foot weight distribution. The conditions for the development of anterior cruciate ligament strain forces are clearly explained.

  5. Atypical presentation of bilateral supplemental maxillary central incisors with unusual talon cusp

    Directory of Open Access Journals (Sweden)

    Sivakumar Nuvvula

    2011-01-01

    Full Text Available Delayed eruption of maxillary permanent central incisors in a child poses a distressing esthetic quandary to parents, by virtue of its location in the dental architecture. Well-aligned anterior teeth add confidence to smile and have enhanced self-esteem, which is critical even in early life. Impaction of the maxillary central incisors compared to third molars or the canines is less reported; bilateral supplemental maxillary central incisors related to impacted permanent maxillary central incisors are rare and one of the supplemental central incisors showing unusual talon is still infrequent. A case of impacted maxillary permanent central incisors related to supplemental maxillary central incisors, with one of them showing an unusual talon cusp, is presented.

  6. Granular flow down a flexible inclined plane

    Directory of Open Access Journals (Sweden)

    Sonar Prasad

    2017-01-01

    Full Text Available Discrete and continuous systems are commonly studied individually, but seldom together. Indeed, granular flows are typically studied through flows over a rigid base. Here, we investigate the behaviour of granular flows over an inclined, flexible base. The flexible base is modeled as a rigid platform mounted on springs and has one degree of freedom. The base vibrations are introduced by the flow. We simulate such flows through a discrete element method and compare with experiments. We find that a flexible base increased the upper limit of the inclination up to which a steady flow is possible by at least 3 degrees. This stabilized zone may have important implications in applications such as conveyor belts and chutes.

  7. Non-dispersive traveling waves in inclined shallow water channels

    International Nuclear Information System (INIS)

    Didenkulova, Ira; Pelinovsky, Efim

    2009-01-01

    Existence of traveling waves propagating without internal reflection in inclined water channels of arbitrary slope is demonstrated. It is shown that traveling non-monochromatic waves exist in both linear and nonlinear shallow water theories in the case of a uniformly inclined channel with a parabolic cross-section. The properties of these waves are studied. It is shown that linear traveling waves should have a sign-variable shape. The amplitude of linear traveling waves in a channel satisfies the same Green's law, which is usually derived from the energy flux conservation for smoothly inhomogeneous media. Amplitudes of nonlinear traveling waves deviate from the linear Green's law, and the behavior of positive and negative amplitudes are different. Negative amplitude grows faster than positive amplitude in shallow water. The phase of nonlinear waves (travel time) is described well by the linear WKB approach. It is shown that nonlinear traveling waves of any amplitude always break near the shoreline if the boundary condition of the full absorption is applied.

  8. Tooth Wear Inclination in Great Ape Molars.

    Science.gov (United States)

    Knight-Sadler, Jordan; Fiorenza, Luca

    2017-01-01

    Primate dietary diversity is reflected in their dental morphology, with differences in size and shape of teeth. In particular, the tooth wear angle can provide insight into a species' ability to break down certain foods. To examine dietary and masticatory information, digitized polygon models of dental casts provide a basis for quantitative analysis of wear associated with tooth attrition. In this study, we analyze and compare the wear patterns of Pongo pygmaeus, Gorilla gorillagorilla and Pan troglodytes schweinfurthii lower molars, focusing on the degree of inclination of specific wear facets. The variation in wear angles appears to be indicative of jaw movements and the specific stresses imposed on food during mastication, reflecting thus the ecology of these species. Orangutans exhibit flatter wear angles, more typical of a diet consisting of hard and brittle foods, while gorillas show a wear pattern with a high degree of inclination, reflecting thus their more leafy diet. Chimpanzees, on the other hand, show intermediate inclinations, a pattern that could be related to their highly variable diet. This method is demonstrated to be a powerful tool for better understanding the relationship between food, mastication and tooth wear processes in living primates, and can be potentially used to reconstruct the diet of fossil species. © 2017 S. Karger AG, Basel.

  9. Management of avulsed permanent maxillary central incisors during endotracheal intubation

    Directory of Open Access Journals (Sweden)

    Ritesh R Kalaskar

    2016-01-01

    Full Text Available Avulsion is serious injury that may encounter during endotracheal intubation and its management often presents a challenge. Replantation of the avulsed tooth can restore esthetic appearance and occlusal function shortly after the injury. The present article describes the management of air-dried maxillary permanent incisors that have been avulsed due to direct laryngoscopy during the induction of general anesthesia for tonsillectomy procedure. The replanted maxillary central incisors had maintained its function and esthetic for 1 year after replantation. Children in a mixed dentition phase are high-risk group children for traumatic dental injury during laryngoscopy; therefore, Anesthetic Departments should have local protocols to refer patients for dental treatment postoperatively in the event of trauma.

  10. Orthodontic management of an impacted maxillary incisor due to odontoma

    Directory of Open Access Journals (Sweden)

    Rahul S Baldawa

    2011-01-01

    Full Text Available Odontomas are a heterogeneous group of jaw bone lesions, classified as odontogenic tumors which usually include well-diversified dental tissues. Odontomas are the most common type of odontogenic tumors and generally they are asymptomatic. Two types of odontomas are described: compound and complex based on either the appearance of well-organized tooth-like structures (compound odontomas or on a mass of disorganized odontogenic tissues (complex odontomas. Compound odontomas have a predilection for the anterior maxilla, whereas complex odontomas have a predilection for the posterior mandible. Odontomas frequently interfere with eruption of teeth leading to their impaction. This is a case report of a 14-year-old girl with an unerupted maxillary right central incisor due to a complex composite odontoma a rare occurrence in anterior maxilla. Surgical excision of the odontoma and orthodontic treatment to get the impacted maxillary right central incisor into alignment is discussed.

  11. Precession of a Spinning Ball Rolling down an Inclined Plane

    Science.gov (United States)

    Cross, Rod

    2015-01-01

    A routine problem in an introductory physics course considers a rectangular block at rest on a plane inclined at angle a to the horizontal. In order for the block not to slide down the incline, the coefficient of sliding friction, µ, must be at least tan a. The situation is similar for the case of a ball rolling down an inclined plane. In order…

  12. On the highly inclined vW leptokurtic asteroid families

    Science.gov (United States)

    Carruba, V.; Domingos, R. C.; Aljbaae, S.; Huaman, M.

    2016-11-01

    vW leptokurtic asteroid families are families for which the distribution of the normal component of the terminal ejection velocity field vW is characterized by a positive value of the γ2 Pearson kurtosis, I.e. they have a distribution with a more concentrated peak and larger tails than the Gaussian one. Currently, eight families are known to have γ2(vW) > 0.25. Among these, three are highly inclined asteroid families, the Hansa, Barcelona, and Gallia families. As observed for the case of the Astrid family, the leptokurtic inclination distribution seems to be caused by the interaction of these families with node secular resonances. In particular, the Hansa and Gallia family are crossed by the s - sV resonance with Vesta, that significantly alters the inclination of some of their members. In this work we use the time evolution of γ2(vW) for simulated families under the gravitational influence of all planets and the three most massive bodies in the main belt to assess the dynamical importance (or lack of) node secular resonances with Ceres, Vesta, and Pallas for the considered families, and to obtain independent constraints on the family ages. While secular resonances with massive bodies in the main belt do not significantly affect the dynamical evolution of the Barcelona family, they significantly increase the γ2(vW) values of the simulated Hansa and Gallia families. Current values of the γ2(vW) for the Gallia family are reached over the estimated family age only if secular resonances with Vesta are accounted for.

  13. Differential expression of syndecan isoforms during mouse incisor amelogenesis.

    Science.gov (United States)

    Muto, Taro; Miyoshi, Keiko; Munesue, Seiichi; Nakada, Hiroshi; Okayama, Minoru; Matsuo, Takashi; Noma, Takafumi

    2007-08-01

    Syndecans are transmembranous heparan sulfate proteoglycans (HSPGs) with covalently attached glycosaminoglycan side-chains located on the cell surface. The mammalian syndecan family is composed of four types of syndecans (syndecan-1 to -4). Syndecans interact with the intracellular cytoskeleton through the cytoplasmic domains of their core proteins and membrane proteins, extracellular enzymes, growth factors, and matrix components, through their heparan-sulfate chains, to regulate developmental processes.Here, as a first step to assess the possible roles of syndecan proteins in amelogenesis, we examined the expression patterns of all syndecan isoforms in continuously growing mouse incisors, in which we can overview major differentiation stages of amelogenesis at a glance. Understanding the expression domain of each syndecan isoform during specific developmental stages seems useful for investigating their physiological roles in amelogenesis. Immunohistochemical analysis of syndecan core proteins in the lower incisors from postnatal day 1 mice revealed spatially and temporally specific expression patterns, with syndecan-1 expressed in undifferentiated epithelial and mesenchymal cells, and syndecan-2, -3, and -4 in more differentiated cells. These findings suggest that each syndecan isoform functions distinctly during the amelogenesis of the incisors of mice.

  14. Multidisciplinary management of impacted central incisors due to supernumerary teeth and an associated dentigerous cyst

    Directory of Open Access Journals (Sweden)

    Ritesh R Kalaskar

    2011-01-01

    Full Text Available Supernumerary teeth are the most common developmental dental anomaly resulting from hyperactivity of dental lamina, dichotomy, environmental factor, or polygenetic process of atavism. Supernumerary teeth present classical oral complication such as impaction of adjacent teeth, crowding, diastema formation, rotation, displacement of teeth, and occlusal interference. A dentigerous cyst associated with anterior supernumerary teeth (mesiodens is rare and accounts for 5% of all dentigerous cysts. The present case reports describe the successful management of the impacted permanent maxillary central incisor positioned high in the vestibule. A combination of surgical and orthodontic techniques was employed to improve treatment outcome with greater hard and soft tissue preservation and to prevent psychological problems. In the surgical phase, supernumerary teeth and dentigerous cyst were removed. Subsequently traction was employed by bonding bracket on the labial surface using closed and open eruption techniques. Successively, fixed orthodontic treatment was started to align permanent maxillary central incisors in an occlusal plane. Thus, combination of surgical and orthodontic method can be the treatment of choice over surgical extraction, implant placement, and surgical repositioning.

  15. Multidisciplinary management of impacted central incisors due to supernumerary teeth and an associated dentigerous cyst.

    Science.gov (United States)

    Kalaskar, Ritesh R; Kalaskar, Ashita R

    2011-01-01

    Supernumerary teeth are the most common developmental dental anomaly resulting from hyperactivity of dental lamina, dichotomy, environmental factor, or polygenetic process of atavism. Supernumerary teeth present classical oral complication such as impaction of adjacent teeth, crowding, diastema formation, rotation, displacement of teeth, and occlusal interference. A dentigerous cyst associated with anterior supernumerary teeth (mesiodens) is rare and accounts for 5% of all dentigerous cysts. The present case reports describe the successful management of the impacted permanent maxillary central incisor positioned high in the vestibule. A combination of surgical and orthodontic techniques was employed to improve treatment outcome with greater hard and soft tissue preservation and to prevent psychological problems. In the surgical phase, supernumerary teeth and dentigerous cyst were removed. Subsequently traction was employed by bonding bracket on the labial surface using closed and open eruption techniques. Successively, fixed orthodontic treatment was started to align permanent maxillary central incisors in an occlusal plane. Thus, combination of surgical and orthodontic method can be the treatment of choice over surgical extraction, implant placement, and surgical repositioning.

  16. Possible relation between pulsar rotation and evolution of magnetic inclination

    Science.gov (United States)

    Tian, Jun

    2018-05-01

    The pulsar timing is observed to be different from predicted by a simple magnetic dipole radiation. We choose eight pulsars whose braking index was reliably determined. Assuming the smaller values of braking index are dominated by the secular evolution of the magnetic inclination, we calculate the increasing rate of the magnetic inclination for each pulsar. We find a possible relation between the rotation frequency of each pulsar and the inferred evolution of the magnetic inclination. Due to the model-dependent fit of the magnetic inclination and other effects, more observational indicators for the change rate of magnetic inclination are needed to test the relation.

  17. PRECISE TULLY-FISHER RELATIONS WITHOUT GALAXY INCLINATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Obreschkow, D.; Meyer, M. [International Centre for Radio Astronomy Research (ICRAR), M468, University of Western Australia, 35 Stirling Hwy, Crawley, WA 6009 (Australia)

    2013-11-10

    Power-law relations between tracers of baryonic mass and rotational velocities of disk galaxies, so-called Tully-Fisher relations (TFRs), offer a wealth of applications in galaxy evolution and cosmology. However, measurements of rotational velocities require galaxy inclinations, which are difficult to measure, thus limiting the range of TFR studies. This work introduces a maximum likelihood estimation (MLE) method for recovering the TFR in galaxy samples with limited or no information on inclinations. The robustness and accuracy of this method is demonstrated using virtual and real galaxy samples. Intriguingly, the MLE reliably recovers the TFR of all test samples, even without using any inclination measurements—that is, assuming a random sin i-distribution for galaxy inclinations. Explicitly, this 'inclination-free MLE' recovers the three TFR parameters (zero-point, slope, scatter) with statistical errors only about 1.5 times larger than the best estimates based on perfectly known galaxy inclinations with zero uncertainty. Thus, given realistic uncertainties, the inclination-free MLE is highly competitive. If inclination measurements have mean errors larger than 10°, it is better not to use any inclinations than to consider the inclination measurements to be exact. The inclination-free MLE opens interesting perspectives for future H I surveys by the Square Kilometer Array and its pathfinders.

  18. Inclined solar chimney for power production

    International Nuclear Information System (INIS)

    Panse, S.V.; Jadhav, A.S.; Gudekar, A.S.; Joshi, J.B.

    2011-01-01

    Highlights: → Solar energy harnessing using inclined face of high mountains as solar chimney. → Solar chimneys with structural stability, ease of construction and lower cost. → Mathematical model developed, using complete (mechanical and thermal) energy balance. → Can harness wind power also, as wind velocities at mountain top add to power output. → Air temperature and velocity increase, as air rises in inclined chimney. - Abstract: The present concept of solar chimney is a tall vertical chimney constructed at the center of a large area, which is the collector. This creates questions about stability and economic viability of the chimney and also demands elaborate engineering techniques for constructing a tall chimney. We suggest geometry of 'Inclined Solar Chimney' (ISC), which is constructed along the face of a high rising mountain, on which maximum solar insolation is incident throughout the year. The chimney and the collector get merged here. This makes the structure stable, cost effective and easy for construction. A mathematical model has been developed considering the total energy balance. It predicts the temperature and velocity and kinetic power of the emerging air draft for some chosen values of other parameters. The model also shows the proportion in which absorbed solar energy is divided into different forms, and hence predicts the dependence of kinetic of emerging air draft upon dimensions of the chimney and properties of materials used. Further, it is shown that external winds enhance the kinetic power of the emerging air. Thus ISC can also harness the wind energy, available at the top of the mountain.

  19. Direct restoration modalities of fractured central maxillary incisors: A multi-levels validated finite elements analysis with in vivo strain measurements.

    Science.gov (United States)

    Davide, Apicella; Raffaella, Aversa; Marco, Tatullo; Michele, Simeone; Syed, Jamaluddin; Massimo, Marrelli; Marco, Ferrari; Antonio, Apicella

    2015-12-01

    To quantify the influence of fracture geometry and restorative materials rigidity on the stress intensity and distribution of restored fractured central maxillary incisors (CMI) with particular investigation of the adhesive interfaces. Ancillary objectives are to present an innovative technology to measure the in vivo strain state of sound maxillary incisors and to present the collected data. A validation experimental biomechanics approach has been associated to finite element analysis. FEA models consisted of CMI, periodontal ligament and the corresponding alveolar bone process. Three models were created representing different orientation of the fracture planes. Three different angulations of the fracture plane in buccal-palatal direction were modeled: the fracture plane perpendicular to the long axis in the buccal-palatal direction (0°); the fracture plane inclined bucco-palatally in apical-coronal direction (-30°); the fracture plane inclined palatal-buccally in apical-coronal direction (+30°). First set of computing runs was performed for in vivo FE-model validation purposes. In the second part, a 50N force was applied on the buccal aspect of the CMI models. Ten patients were selected and subjected to the strain measurement of CMI under controlled loading conditions. The main differences were noticed in the middle and incisal thirds of incisors crowns, due to the presence of the incisal portion restoration. The stress intensity in -30° models is increased in the enamel structure close to the restoration, due to a thinning of the remaining natural tissues. The rigidity of the restoring material slightly reduces such phenomenon. -30° model exhibits the higher interfacial stress in the adhesive layer with respect to +30° and 0° models. The lower stress intensity was noticed in the 0° models, restoration material rigidity did not influenced the interfacial stress state in 0° models. On the contrary, material rigidity influenced the interfacial stress state

  20. Upper Incisor Changes Due to Modifying the Point of Application of Forces during Space Closure in MBT Technique

    Directory of Open Access Journals (Sweden)

    H. Ravanmehr

    2004-06-01

    Full Text Available Statement of Problem: A recent technique (MBT has been introduced for easy and efficient orthodontic treatment by means of straight wire fixed appliances. Although this technique has many advantages, in space closure stage causes up righting problem in upper incisors, which should be adjusted by applying additional torque in anterior region.Purpose: The purpose of this clinical trial was to determine whether there is a significant difference in final incisor inclination (torque of two groups one treated with MBT technique and the other by changing the point of application of the closing force (in anterior region.Materials and Methods: Twelve patients (8 girls, 4 boys with Cl I malocclusion and crowding, whom were candidate for first premolars extraction, were selected.For space closure, 6 anterior teeth (canine to canine in upper and lower jaws ligated and the applied force was from the hooks on canines to hooks on the first molars.After space closure the results compared with the results of a previous study which treatment plan was according to original MBT technique (anterior hooks soldered to arch wire. Forces applied randomly among quadrants by NiTi coil spring (American Orthodontics Co. or active tie backs with elastic modules (Dentaurum Co.Results: The results showed a statistically significant difference between final torques of two techniques (P=0.0001. Also, the rate of space closure with NiTi coils was significantly greater than active tie back (P=0.0001.Conclusion: Anchorage loss in two groups compared and the results indicated significantly lower anchorage loss in NiTi coil spring group (P=0.035.

  1. Ion Feedback Suppression Using Inclined MCP Holes in a Single-MCP+Micromegas+Pads Detector

    International Nuclear Information System (INIS)

    Va'vra, J.; Sumiyoshi, T.

    2005-01-01

    We show that the ion backflow to photocathode can be completely suppressed if one uses inclined MCP holes in a presence of magnetic field. The inclined hole angles are chosen to be aligned with the Lorentz electron angle allowing the electron transmission and amplification, while positive ions, traveling along a different angle, are caught on the MCP hole walls. The detector under investigation is a new gaseous detector structure based on a tandem of two parts, a single MCP (Microchannel) plate, a Micromegas with pad readout. We are aiming to develop a gaseous photon detector with the Bialkali photocathode, however, one could use some ideas in the paper for other types of detectors

  2. Changes in the Relative Balance of Approach and Avoidance Inclinations to Use Alcohol Following Cue Exposure Vary in Low and High Risk Drinkers

    Directory of Open Access Journals (Sweden)

    Ross C. Hollett

    2017-05-01

    Full Text Available According to the ambivalence model of craving, alcohol craving involves the dynamic interplay of separate approach and avoidance inclinations. Cue-elicited increases in approach inclinations are posited to be more likely to result in alcohol consumption and risky drinking behaviors only if unimpeded by restraint inclinations. Current study aims were (1 to test if changes in the net balance between approach and avoidance inclinations following alcohol cue exposure differentiate between low and high risk drinkers, and (2 if this balance is associated with alcohol consumption on a subsequent taste test. In two experiments (N = 60; N = 79, low and high risk social drinkers were exposed to alcohol cues, and pre- and post- approach and avoidance inclinations measured. An ad libitum alcohol consumption paradigm and a non-alcohol exposure condition were also included in Study 2. Cue-elicited craving was characterized by a predominant approach inclination only in the high risk drinkers. Conversely, approach inclinations were adaptively balanced by equally strong avoidance inclinations when cue-elicited craving was induced in low risk drinkers. For these low risk drinkers with the balanced craving profile, neither approach or avoidance inclinations predicted subsequent alcohol consumption levels during the taste test. Conversely, for high risk drinkers, where the approach inclination predominated, each inclination synergistically predicted subsequent drinking levels during the taste test. In conclusion, results support the importance of assessing both approach and avoidance inclinations, and their relative balance following alcohol cue exposure. Specifically, this more comprehensive assessment reveals changes in craving profiles that are not apparent from examining changes in approach inclinations alone, and it is this shift in the net balance that distinguishes high from low risk drinkers.

  3. Surgical Management of Mandibular Central Incisors with Dumbbell Shaped Periapical Lesion: A Case Report

    Directory of Open Access Journals (Sweden)

    Roopadevi Garlapati

    2014-01-01

    Full Text Available Dental traumatic injuries may affect the teeth and alveolar bone directly or indirectly. Pulpal necrosis and chronic and apical periodontitis with cystic changes are the most common sequelae of the dental traumatic injuries, if the teeth are not treated immediately. This case report focuses on the conventional and surgical management of mandibular central incisors. A twenty-four-year-old male patient presented with pain in the mandibular central incisors. Radiographic examination revealed mandibular central incisors with dumbbell shaped periapical lesion. After root canal treatment, parendodontic surgery was performed for mandibular central incisors. After one-year recall examination, the teeth were asymptomatic and periapical lesion had healed.

  4. Distribution and characteristics of molar-incisor hypomineralization

    Directory of Open Access Journals (Sweden)

    Janković Svjetlana

    2014-01-01

    Full Text Available Background/Aim. Developmental disorders of teeth are the problems that are becoming more present in pediatric dentistry, especially on first permanent molars and incisors. Molar Incisor Hypomineralization (MIH is proposed term for this phenomenon. The aim of this study was to establish the MIH prevalence in children living in the Foča municipality (Bosnia and Herzegovina as well as to assess characteristics and expression of hypomineralization within the tested population. Methods. A total of 141 children from the Foča municipality, 8 years of age, were included in this study. Criteria according to Weerhejm have been used for diagnosis of hypomineralization: demarcated opacity (DO, post-eruptive breakdown (PEB, atypical restoration (AR, extracted molars due to MIH (E-MIH and unerupted tooth (UT. Level and the prominence of color changes have been determined for patients with DO, PEB and AR. Results. MIH in this area was present in 12.8% of children. The prevalence of MIH changes expressed in percentages was as follows: DO was at 9.2%, PEB in 3.5%, AR in 5.6%, while E-MIH was 5.6%. A total of 9.9% of the examinees had mild, 5.6% moderate, and 7.8% severe form of MIH. White form of MIH defects was found in 9.9% of the examinees, white-yellow one in 5.6% and yellow-brown color in 3.5% of the examined children. These changes were more often present in the lower jaw (60.3%. In total, 6.4% of children had these changes present only on molars, while 6.4% of them both on molars and incisors simultaneously. Conclusion. A total of 12.8% of the examinees with MIH is not to be disregarded. With timely diagnosis, prevention and therapy complications could be avoided or mitigated.

  5. Bilateral Complete and Incomplete Fusion of Incisors and its Management.

    Science.gov (United States)

    Da Costa, Godwin Clovis; Chalakkal, Paul; De Souza, Neil; Gavhane, Sanket

    2017-01-01

    This case report highlights the management of a case of bilateral complete and incomplete fusion of maxillary incisors in a 10-year-old child. A mock-up was done on the diagnostic cast. Pretreatment esthetic evaluation was done using bis-acryl composite temporaries which were transferred intraorally from the diagnostic cast using a putty index. An incisal overlap veneer preparation was done, following which, an IPS e-max veneer was cemented. A digital mock-up was carried out using the Adobe Photoshop and Corel Draw softwares to aid in laboratorial fabrication of the veneer.

  6. Bilateral complete and incomplete fusion of incisors and its management

    Directory of Open Access Journals (Sweden)

    Godwin Clovis Da Costa

    2017-01-01

    Full Text Available This case report highlights the management of a case of bilateral complete and incomplete fusion of maxillary incisors in a 10-year-old child. A mock-up was done on the diagnostic cast. Pretreatment esthetic evaluation was done using bis-acryl composite temporaries which were transferred intraorally from the diagnostic cast using a putty index. An incisal overlap veneer preparation was done, following which, an IPS e-max veneer was cemented. A digital mock-up was carried out using the Adobe Photoshop and Corel Draw softwares to aid in laboratorial fabrication of the veneer.

  7. Maxillary Central Incisor with Two Roots: A Case Report

    Directory of Open Access Journals (Sweden)

    L. Khojastehpour

    2005-06-01

    Full Text Available A 16 year old female was referred to an oral and maxillofacial radiologist for evaluation of a radiolucent area at mesial radicular aspect of right maxillary central incisor which was detected accidentally during pre-orthodontic treatment check ups. Clinicalexamination showed no particular signs or symptoms except for slightly tenderness to lateral percussion. Second radiograph with altered horizontal angulations showed a mesial supernumerary root which the radiolucency seemed to be associated with that. Inorder to treat the tooth, the composite filling was removed and canals were cleaned,shaped, and obturated by lateral condensation technique.

  8. Neural extrapolation of motion for a ball rolling down an inclined plane.

    Science.gov (United States)

    La Scaleia, Barbara; Lacquaniti, Francesco; Zago, Myrka

    2014-01-01

    It is known that humans tend to misjudge the kinematics of a target rolling down an inclined plane. Because visuomotor responses are often more accurate and less prone to perceptual illusions than cognitive judgments, we asked the question of how rolling motion is extrapolated for manual interception or drawing tasks. In three experiments a ball rolled down an incline with kinematics that differed as a function of the starting position (4 different positions) and slope (30°, 45° or 60°). In Experiment 1, participants had to punch the ball as it fell off the incline. In Experiment 2, the ball rolled down the incline but was stopped at the end; participants were asked to imagine that the ball kept moving and to punch it. In Experiment 3, the ball rolled down the incline and was stopped at the end; participants were asked to draw with the hand in air the trajectory that would be described by the ball if it kept moving. We found that performance was most accurate when motion of the ball was visible until interception and haptic feedback of hand-ball contact was available (Experiment 1). However, even when participants punched an imaginary moving ball (Experiment 2) or drew in air the imaginary trajectory (Experiment 3), they were able to extrapolate to some extent global aspects of the target motion, including its path, speed and arrival time. We argue that the path and kinematics of a ball rolling down an incline can be extrapolated surprisingly well by the brain using both visual information and internal models of target motion.

  9. Neural extrapolation of motion for a ball rolling down an inclined plane.

    Directory of Open Access Journals (Sweden)

    Barbara La Scaleia

    Full Text Available It is known that humans tend to misjudge the kinematics of a target rolling down an inclined plane. Because visuomotor responses are often more accurate and less prone to perceptual illusions than cognitive judgments, we asked the question of how rolling motion is extrapolated for manual interception or drawing tasks. In three experiments a ball rolled down an incline with kinematics that differed as a function of the starting position (4 different positions and slope (30°, 45° or 60°. In Experiment 1, participants had to punch the ball as it fell off the incline. In Experiment 2, the ball rolled down the incline but was stopped at the end; participants were asked to imagine that the ball kept moving and to punch it. In Experiment 3, the ball rolled down the incline and was stopped at the end; participants were asked to draw with the hand in air the trajectory that would be described by the ball if it kept moving. We found that performance was most accurate when motion of the ball was visible until interception and haptic feedback of hand-ball contact was available (Experiment 1. However, even when participants punched an imaginary moving ball (Experiment 2 or drew in air the imaginary trajectory (Experiment 3, they were able to extrapolate to some extent global aspects of the target motion, including its path, speed and arrival time. We argue that the path and kinematics of a ball rolling down an incline can be extrapolated surprisingly well by the brain using both visual information and internal models of target motion.

  10. Identification of families among highly inclined asteroids

    Science.gov (United States)

    Gil-Hutton, R.

    2006-07-01

    A dataset of 3652 high-inclination numbered asteroids was analyzed to search for dynamical families. A fully automated multivariate data analysis technique was applied to identify the groupings. Thirteen dynamical families and twenty-two clumps were found. When taxonomic information is available, the families show cosmochemical consistency and support an interpretation based on a common origin from a single parent body. Four families and three clumps found in this work show a size distribution which is compatible with a formation due to a cratering event on the largest member of the family, and also three families have B- or related taxonomic types members, which represents a 14% of the B-types classified by Bus and Binzel [2002. Icarus 158, 146-177].

  11. On liquid films on an inclined plate

    KAUST Repository

    BENILOV, E. S.

    2010-08-18

    This paper examines two related problems from liquid-film theory. Firstly, a steady-state flow of a liquid film down a pre-wetted plate is considered, in which there is a precursor film in front of the main film. Assuming the former to be thin, a full asymptotic description of the problem is developed and simple analytical estimates for the extent and depth of the precursor film\\'s influence on the main film are provided. Secondly, the so-called drag-out problem is considered, where an inclined plate is withdrawn from a pool of liquid. Using a combination of numerical and asymptotic means, the parameter range where the classical Landau-Levich-Wilson solution is not unique is determined. © 2010 Cambridge University Press.

  12. Impinging Water Droplets on Inclined Glass Surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Armijo, Kenneth Miguel [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Lance, Blake [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Ho, Clifford K. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-09-01

    Multiphase computational models and tests of falling water droplets on inclined glass surfaces were developed to investigate the physics of impingement and potential of these droplets to self-clean glass surfaces for photovoltaic modules and heliostats. A multiphase volume-of-fluid model was developed in ANSYS Fluent to simulate the impinging droplets. The simulations considered different droplet sizes (1 mm and 3 mm), tilt angles (0°, 10°, and 45°), droplet velocities (1 m/s and 3 m/s), and wetting characteristics (wetting=47° contact angle and non-wetting = 93° contact angle). Results showed that the spread factor (maximum droplet diameter during impact divided by the initial droplet diameter) decreased with increasing inclination angle due to the reduced normal force on the surface. The hydrophilic surface yielded greater spread factors than the hydrophobic surface in all cases. With regard to impact forces, the greater surface tilt angles yielded lower normal forces, but higher shear forces. Experiments showed that the experimentally observed spread factor (maximum droplet diameter during impact divided by the initial droplet diameter) was significantly larger than the simulated spread factor. Observed spread factors were on the order of 5 - 6 for droplet velocities of ~3 m/s, whereas the simulated spread factors were on the order of 2. Droplets were observed to be mobile following impact only for the cases with 45° tilt angle, which matched the simulations. An interesting phenomenon that was observed was that shortly after being released from the nozzle, the water droplet oscillated (like a trampoline) due to the "snapback" caused by the surface tension of the water droplet being released from the nozzle. This oscillation impacted the velocity immediately after the release. Future work should evaluate the impact of parameters such as tilt angle and surface wettability on the impact of particle/soiling uptake and removal to investigate ways that

  13. The Gothic arch (needle point) tracing and condylar inclination.

    Science.gov (United States)

    el-Gheriani, A S; Winstanley, R B

    1987-11-01

    The records of 11 patients referred for treatment of TMJ disorders were used to compare condylar inclination found by drawing a tangent and by using a mathematic technique. Needle point tracing angles were also measured for the same patients and were compared with the condylar inclination. It can be concluded that (1) the mathematic technique outlined records a more accurate condylar angulation, and (2) there is a great variation in condylar inclination values between patients and between left and right sides of the same patient, and (3) there is no direct relationship between condylar inclination and the needle point tracing angle.

  14. Psychosocial Determinants of Romantic Inclination Among Indian Youth

    Directory of Open Access Journals (Sweden)

    D. Barani Ganth

    2017-10-01

    Full Text Available The present study was conducted with the aim of understanding the psychosocial determinants of romantic inclination among youth in India. We involved 779 student participants from a large central university in south India in the age range of 18-24 years. The participants filled measures on romantic inclination, personality, attachment style, interpersonal attraction, and social influence on romantic relationship in addition to a questionnaire on demographic information and relationship history. Analysis of the data revealed that males showed higher level of romantic inclination than females. Those who had current/past involvement in a romantic relationship (Lovers showed higher levels of romantic inclination than those who had never involved in a romantic relationship (Non-lovers. Parents’ type of marriage (Love/arranged, close fiends’ involvement in romantic relationship too had a discriminatory role in romantic inclination. Romantic inclination was significantly related to personality factors, attachment style, media and peer influences on romantic relationships and interpersonal attraction. Extraversion, openness to experience, agreeableness, media influence, peer influence, secure attachment and physical attraction emerged as significant predictors of romantic inclination in a regression model. Structural Equations Modeling (SEM indicated that personality, attachment style and interpersonal attraction had a significant influence on romantic inclination mediated by both media and peer influences. Romantic inclination in turn significantly predicted romantic relationship status.

  15. Enhanced photovoltaic performance of an inclined nanowire array solar cell.

    Science.gov (United States)

    Wu, Yao; Yan, Xin; Zhang, Xia; Ren, Xiaomin

    2015-11-30

    An innovative solar cell based on inclined p-i-n nanowire array is designed and analyzed. The results show that the inclined geometry can sufficiently increase the conversion efficiency of solar cells by enhancing the absorption of light in the active region. By tuning the nanowire array density, nanowire diameter, nanowire length, as well as the proportion of intrinsic region of the inclined nanowire solar cell, a remarkable efficiency in excess of 16% can be obtained in GaAs. Similar results have been obtained in InP and Si nanowire solar cells, demonstrating the universality of the performance enhancement of inclined nanowire arrays.

  16. Class II malocclusion with accentuated occlusal plane inclination corrected with miniplate: a case report

    Science.gov (United States)

    Farret, Marcel Marchiori; Farret, Milton M. Benitez

    2016-01-01

    ABSTRACT Introduction: A canted occlusal plane presents an unesthetic element of the smile. The correction of this asymmetry has been typically considered difficult by orthodontists, as it requires complex mechanics and may sometimes even require orthognathic surgery. Objective: This paper outlines the case of a 29-year-old woman with Class II malocclusion, pronounced midline deviation and accentuated occlusal plane inclination caused by mandibular deciduous molar ankylosis. Methods: The patient was treated with a miniplate used to provide anchorage in order to intrude maxillary teeth and extrude mandibular teeth on one side, thus eliminating asymmetry. Class II was corrected on the left side by means of distalization, anchored in the miniplate as well. On the right side, maxillary first premolar was extracted and molar relationship was kept in Class II, while canines were moved to Class I relationship. The patient received implant-prosthetic rehabilitation for maxillary left lateral incisor and mandibular left second premolar. Results: At the end of treatment, Class II was corrected, midlines were matched and the canted occlusal plane was totally corrected, thereby improving smile function and esthetics. PMID:27409658

  17. Class II malocclusion with accentuated occlusal plane inclination corrected with miniplate: a case report

    Directory of Open Access Journals (Sweden)

    Marcel Marchiori Farret

    Full Text Available ABSTRACT Introduction: A canted occlusal plane presents an unesthetic element of the smile. The correction of this asymmetry has been typically considered difficult by orthodontists, as it requires complex mechanics and may sometimes even require orthognathic surgery. Objective: This paper outlines the case of a 29-year-old woman with Class II malocclusion, pronounced midline deviation and accentuated occlusal plane inclination caused by mandibular deciduous molar ankylosis. Methods: The patient was treated with a miniplate used to provide anchorage in order to intrude maxillary teeth and extrude mandibular teeth on one side, thus eliminating asymmetry. Class II was corrected on the left side by means of distalization, anchored in the miniplate as well. On the right side, maxillary first premolar was extracted and molar relationship was kept in Class II, while canines were moved to Class I relationship. The patient received implant-prosthetic rehabilitation for maxillary left lateral incisor and mandibular left second premolar. Results: At the end of treatment, Class II was corrected, midlines were matched and the canted occlusal plane was totally corrected, thereby improving smile function and esthetics.

  18. A central incisor with 4 independent root canals: a case report

    NARCIS (Netherlands)

    Aznar Portoles, C.; Moinzadeh, A.T.; Shemesh, H.

    2015-01-01

    The maxillary central incisor is the tooth with the least anatomic variations. Despite the fact that several studies have reported a prevalence of 100% for the presence of a single canal, root canal aberrations of maxillary central incisors with up to 3 canals have also been reported. Such cases

  19. Orthodontic Management of Congenitally Missing Maxillary Lateral Incisors: A Case Report

    OpenAIRE

    Paduano, Sergio; Cioffi, Iacopo; Rongo, Roberto; Cupo, Antonello; Bucci, Rosaria; Valletta, Rosa

    2014-01-01

    This case report describes the orthodontic treatment of a woman, aged 15 years, with permanent dentition, brachyfacial typology, with congenitally missing maxillary lateral incisors. Multibracket straightwire fixed appliance was used to open the space for dental implant placement, and treat the impaired occlusion. The missing lateral incisors were substituted with oral implants.

  20. Orthodontic Management of Congenitally Missing Maxillary Lateral Incisors: A Case Report

    Directory of Open Access Journals (Sweden)

    Sergio Paduano

    2014-01-01

    Full Text Available This case report describes the orthodontic treatment of a woman, aged 15 years, with permanent dentition, brachyfacial typology, with congenitally missing maxillary lateral incisors. Multibracket straightwire fixed appliance was used to open the space for dental implant placement, and treat the impaired occlusion. The missing lateral incisors were substituted with oral implants.

  1. Orthodontic intrusion of maxillary incisors: a 3D finite element method study

    Directory of Open Access Journals (Sweden)

    Armando Yukio Saga

    2016-02-01

    Full Text Available Objective: In orthodontic treatment, intrusion movement of maxillary incisors is often necessary. Therefore, the objective of this investigation is to evaluate the initial distribution patterns and magnitude of compressive stress in the periodontal ligament (PDL in a simulation of orthodontic intrusion of maxillary incisors, considering the points of force application. Methods: Anatomic 3D models reconstructed from cone-beam computed tomography scans were used to simulate maxillary incisors intrusion loading. The points of force application selected were: centered between central incisors brackets (LOAD 1; bilaterally between the brackets of central and lateral incisors (LOAD 2; bilaterally distal to the brackets of lateral incisors (LOAD 3; bilaterally 7 mm distal to the center of brackets of lateral incisors (LOAD 4. Results and Conclusions: Stress concentrated at the PDL apex region, irrespective of the point of orthodontic force application. The four load models showed distinct contour plots and compressive stress values over the midsagittal reference line. The contour plots of central and lateral incisors were not similar in the same load model. LOAD 3 resulted in more balanced compressive stress distribution.

  2. The Effect of Terrain Inclination on Performance and the Stability Region of Two-Wheeled Mobile Robots

    Directory of Open Access Journals (Sweden)

    Zareena Kausar

    2012-11-01

    Full Text Available Two-wheeled mobile robots (TWMRs have a capability of avoiding the tip-over problem on inclined terrain by adjusting the centre of mass position of the robot body. The effects of terrain inclination on the robot performance are studied to exploit this capability. Prior to the real-time implementation of position control, an estimation of the stability region of the TWMR is essential for safe operation. A numerical method to estimate the stability region is applied and the effects of inclined surfaces on the performance and stability region of the robot are investigated. The dynamics of a TWMR is modelled on a general uneven terrain and reduced for cases of inclined and horizontal flat terrain. A full state feedback (FSFB controller is designed based on optimal gains with speed tracking on a horizontal flat terrain. The performance and stability regions are simulated for the robot on a horizontal flat and inclined terrain with the same controller. The results endorse a variation in equilibrium points and a reduction in stability region for robot motion on inclined terrain.

  3. Experimental study on characteristics of interfacial parameter distribution for upward bubbly flow in inclined tube

    International Nuclear Information System (INIS)

    Xing Dianchuan; Yan Changqi; Sun Licheng; Liu Jingyu

    2013-01-01

    Experimental study on characteristics of interfacial parameter distribution for air-water bubbly flow in an inclined circular tube was performed by using the double sensor probe method. Parameters including radial distributions of local void fraction, bubble passing frequency, interfacial area concentration and bubble equivalent diameter were measured using the probe. The inner diameter of test section is 50 mm, and the liquid superficial velocity is 0.144 m/s, with the gas superficial velocity ranging from 0 to 0.054 m/is. The results show that bubbles obviously move toward the upper wall and congregate. The local interfacial area concentration, bubble passing frequency and void fraction have similar radial distribution profiles. Different from the vertical condition, for a cross-sectional area of the test section, the peak value near the upper side increases, while decreases or even disappears near the underside. The local parameter increases as the radial positions change from lower to upper location, and the increased slope becomes larger as the inclination angles increase. The equivalent bubble diameter doesn't vary with radial position, superficial gas velocity and inclination angle, and bubble aggregation and breaking up nearly doesn't occur. The mechanism of effects of inclination on local parameter distribution for bubbly flow is explained by analyzing the transverse force governing the bubble motion. (authors)

  4. Orthodontic management of bilateral maxillary canine-first premolar transposition and bilateral agenesis of maxillary lateral incisors: a case report.

    Science.gov (United States)

    Di Palma, Elena; Di Giuseppe, Biagio; Tepedino, Michele; Chimenti, Claudio

    2015-01-01

    Maxillary canine-first premolar transposition (Mx.C.P1) is an uncommon dental positional anomaly that may create many orthodontic problems from both esthetic and functional points of view. In this report we show the orthodontic management of a case of Mx.C.P1 associated with bilateral maxillary lateral incisor agenesis and unilateral mandibular second premolar agenesis The patient was treated with a multibracket appliance and the extraction of the lower premolar. treatment was completed without the need for any prosthetic replacement.

  5. Smile esthetics: Impact of variations in the vertical and horizontal dimensions of the maxillary lateral incisors

    Science.gov (United States)

    Al Taki, Amjad; Hamdan, Ahmad Mohammad; Mustafa, Ziad; Hassan, Mawada; Abu-Alhuda, Sami

    2017-01-01

    Objective: The purpose of this study was to determine the perception of trained dental professionals and laypersons toward the esthetic impact of variations in the vertical position, width, and gingival height of the maxillary lateral incisor. Materials and Methods: The present study analyzed the perspective of smile photographs by dental professionals such as “fifty orthodontics and fifty general dental practitioners (GDPs)” as well as fifty laypersons, consisting of an equal number of male and female participants. Photographs edited to depict alteration of golden proportion, incisal length, and gingival height of lateral incisor. SPSS software was used to analyze the data and determine the significant difference within all the participants, at 0.05% level (95% confidence interval). Results: There was no significant difference in ranking between the genders. Golden proportion of 62%–67% were ranked the highest by orthodontists, whereas GDPs and laypersons preferred 67%. Regarding gingival display, corrected height of −0.5 and −1 mm received highest ranking from all the three groups. In case of lateral incisal length, −0.5 mm was ranked highest by laypersons, in contrast to −1 mm by orthodontists and GDPs. Conclusion: Specific differences were observed in the ranking of smile esthetics by health-care professionals and laypersons. Golden proportion of 62% and 67% were ranked the highest by orthodontists, whereas GDPs and laypersons preferred 67%. Corrected gingival height of −0.5 and −1 mm received highest ranking from all the three groups. In case of lateral incisal length, −0.5 mm was ranked highest by laypersons, in contrast to −1 mm by orthodontists and GDPs. PMID:29279680

  6. Diagnostic performance of increased overjet in Class II division 1 malocclusion and incisor trauma.

    Science.gov (United States)

    Baccetti, Tiziano; Giuntini, Veronica; Vangelisti, Andrea; Darendeliler, M Ali; Franchi, Lorenzo

    2010-01-01

    The objectives of this study were: 1) to evaluate the associations between an increased overjet (IO) and other dentoskeletal characteristics of Class II division 1 malocclusions in the mixed dentition; 2) to assess whether Class II division 1 malocclusions or rather an increased overjet per se is a risk factor for upper incisor trauma (UIT). A sample of 900 mixed dentition subjects, was observed by clinical inspection, analysis of dental casts, and lateral cephalograms. The diagnostic performance of IO (overjet ≥ 7 mm) was evaluated in relation to other Class II dentoskeletal features (Class II molar and canine relationships, and skeletal Class II relationships). Secondly, the diagnostic performance of IO and of the other Class II dentoskeletal components was tested with regard to the prevalence of UIT. Diagnostic performance was assessed by odds ratio and positive likelihood ratio. The diagnostic performance of IO with regard to the other dentoskeletal components of Class II malocclusions was not significant. The only Class II features associated significantly with an increased risk of UIT was IO. When used as an isolated occlusal feature, IO is not a valid diagnostic indicator for Class II division 1 malocclusions. An increased overjet per se, and not Class II malocclusions, appears to be a significant risk factor for UIT. These findings recommend discrimination between clinical conditions showing an isolated IO from comprehensive Class II malocclusions during diagnosis, analysis of treatment outcomes, and evaluation of the risk of upper incisor trauma. Copyright © 2010 Società Italiana di Ortodonzia SIDO. Published by Elsevier Srl. All rights reserved.

  7. 47 CFR 25.280 - Inclined orbit operations.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Inclined orbit operations. 25.280 Section 25.280 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER SERVICES SATELLITE COMMUNICATIONS Technical Operations § 25.280 Inclined orbit operations. (a) Satellite operators may commence...

  8. Removable thermoplastic appliances modified by incisal cuts show altered biomechanical properties during tipping of a maxillary central incisor.

    Science.gov (United States)

    Brockmeyer, Phillipp; Kramer, Katharina; Böhrnsen, Florian; Gruber, Rudolf Matthias; Batschkus, Sarah; Rödig, Tina; Hahn, Wolfram

    2017-08-28

    The present study aimed to evaluate the force delivery of removable thermoplastic appliances (RTAs), modified by different sized incisal cuts, during tipping of a maxillary central incisor in palatal and vestibular direction. Forty-five RTAs from three different materials (Biolon®, Erkodur®, Ideal Clear®) of the same thickness (1 mm) were used. Analysis was performed on a separated maxillary central incisor which was part of a resin model with a complete dentition. In 15 RTAs, of different material, a cut was inserted at the incisal edge of tooth 11. In 15 other appliances, the cut was extended to teeth 12 and 21. Fifteen aligners remained uncut. The experimental tooth was tipped starting from the zero position in 0.05° steps to a maximal deflection of ± 0.42° of the incisal edge in vestibular and palatal direction, after positioning the RTA onto the model. The horizontal (Fx) and the vertical (Fz) force components were decreased by approximately half with increasing cut size. Fz values changed during palatal tipping from a weak intrusive force, for aligners without cut, to an extrusive force with increasing cut size. Compared to both other materials used (Erkodur® and Ideal Clear®), the Biolon® aligners showed significantly higher Fx and Fz values (p < 0.0001, respectively). RTAs modified by different sized incisal cuts show altered biomechanical properties and an inversion of the vertical force component, during tipping of a maxillary central incisor.

  9. Removable thermoplastic appliances modified by incisal cuts show altered biomechanical properties during tipping of a maxillary central incisor

    Directory of Open Access Journals (Sweden)

    Phillipp Brockmeyer

    2017-08-01

    Full Text Available Abstract Background The present study aimed to evaluate the force delivery of removable thermoplastic appliances (RTAs, modified by different sized incisal cuts, during tipping of a maxillary central incisor in palatal and vestibular direction. Methods Forty-five RTAs from three different materials (Biolon®, Erkodur®, Ideal Clear® of the same thickness (1 mm were used. Analysis was performed on a separated maxillary central incisor which was part of a resin model with a complete dentition. In 15 RTAs, of different material, a cut was inserted at the incisal edge of tooth 11. In 15 other appliances, the cut was extended to teeth 12 and 21. Fifteen aligners remained uncut. The experimental tooth was tipped starting from the zero position in 0.05° steps to a maximal deflection of ± 0.42° of the incisal edge in vestibular and palatal direction, after positioning the RTA onto the model. Results The horizontal (Fx and the vertical (Fz force components were decreased by approximately half with increasing cut size. Fz values changed during palatal tipping from a weak intrusive force, for aligners without cut, to an extrusive force with increasing cut size. Compared to both other materials used (Erkodur® and Ideal Clear®, the Biolon® aligners showed significantly higher Fx and Fz values (p < 0.0001, respectively. Conclusions RTAs modified by different sized incisal cuts show altered biomechanical properties and an inversion of the vertical force component, during tipping of a maxillary central incisor.

  10. Conservative restoration of a traumatically involved central incisor.

    Science.gov (United States)

    Bassett, Joyce

    2012-04-01

    The use of a direct composite material known for excellent polishability, polish retention, and wear resistance is described in this case of a fractured central incisor restoration. The method used enabled the clinician to conserve tooth structure and maintain full control of the outcome while creating an esthetically imperceptible, reliable, and durable restoration for a young male patient. Emphasized in this case are the techniques of layering, contouring, and polishing of a nanocomposite used to maximize esthetics and meet patient expectations. To further ensure imperceptibility, the author recommends first facilitating color shade selection for both body and dentin-especially in two-shade or multiple-shade restorations-by placing the composite in its planned area of the restoration and curing it in its proper thickness to allow a preview and recipe map.

  11. UNBIASED INCLINATION DISTRIBUTIONS FOR OBJECTS IN THE KUIPER BELT

    International Nuclear Information System (INIS)

    Gulbis, A. A. S.; Elliot, J. L.; Adams, E. R.; Benecchi, S. D.; Buie, M. W.; Trilling, D. E.; Wasserman, L. H.

    2010-01-01

    Using data from the Deep Ecliptic Survey (DES), we investigate the inclination distributions of objects in the Kuiper Belt. We present a derivation for observational bias removal and use this procedure to generate unbiased inclination distributions for Kuiper Belt objects (KBOs) of different DES dynamical classes, with respect to the Kuiper Belt plane. Consistent with previous results, we find that the inclination distribution for all DES KBOs is well fit by the sum of two Gaussians, or a Gaussian plus a generalized Lorentzian, multiplied by sin i. Approximately 80% of KBOs are in the high-inclination grouping. We find that Classical object inclinations are well fit by sin i multiplied by the sum of two Gaussians, with roughly even distribution between Gaussians of widths 2.0 +0.6 -0.5 0 and 8.1 +2.6 -2.1 0 . Objects in different resonances exhibit different inclination distributions. The inclinations of Scattered objects are best matched by sin i multiplied by a single Gaussian that is centered at 19.1 +3.9 -3.6 0 with a width of 6.9 +4.1 -2.7 0 . Centaur inclinations peak just below 20 0 , with one exceptionally high-inclination object near 80 0 . The currently observed inclination distribution of the Centaurs is not dissimilar to that of the Scattered Extended KBOs and Jupiter-family comets, but is significantly different from the Classical and Resonant KBOs. While the sample sizes of some dynamical classes are still small, these results should begin to serve as a critical diagnostic for models of solar system evolution.

  12. [Molar incisor hypomineralization (MIH)--a literature review].

    Science.gov (United States)

    Gotler, M; Ratson, T

    2010-04-01

    MIH was defined by Weerheijm (2001) as "hypomineralisation of systemic origin of 1-4 permanent first molars, frequently associated with affected incisors". The prevalence of MIH varies between 2.8% and 25%, dependent upon the study. At their sixth congress in 2003, The European Association of pediatric dentistry defined criteria for diagnosis of the phenomena. It included the presence of demarcated opacity, posteruptive enamel breakdown, atypical restoration, extracted molar due to MIH and unerupted teeth. According to the teeth involved and to the time of the crown formation, researches focused on environmental and systemic conditions as possible reasons for MIH.The etiologies were divided into five groups: Exposure to environmental contaminants, pre/peri and neonatal problems, exposure to fluoride, common childhood illnesses and medically compromised children. The clinical implications include highly sensitive teeth, difficulty to achieve adequate anesthesia, behavioral problems and anxiety, rapid progression of caries and the esthetic implications. A six step approach to management was described suggested: risk identification, early diagnosis, remineralization and desensitization, prevention of caries and posteruption breakdown, restorations and extractions and finally maintenance. Restoring an affected molar can vary from adhesive intra coronal restorations (resin composite is the material of choice) to extra coronal restorations (e.g. preformed metal crown). Esthetic solutions to affected incisors may include microabrasion (that shows little improvement) and resin composite or porcelain veneer. The key for a successful treatment is early diagnosis, intense follow up and usage of remineralizating agents as soon as the teeth erupt. There is still need for further research to clarify the etiological factors and improve the durability of restoration in affected teeth.

  13. Movements of a Sphere Moving Over Smooth and Rough Inclines

    Science.gov (United States)

    Jan, Chyan-Deng

    1992-01-01

    The steady movements of a sphere over a rough incline in air, and over smooth and rough inclines in a liquid were studied theoretically and experimentally. The principle of energy conservation was used to analyze the translation velocities, rolling resistances, and drag coefficients of a sphere moving over the inclines. The rolling resistance to the movement of a sphere from the rough incline was presumed to be caused by collisions and frictional slidings. A varnished wooden board was placed on the bottom of an experimental tilting flume to form a smooth incline and a layer of spheres identical to the sphere moving over them was placed on the smooth wooden board to form a rough incline. Spheres used in the experiments were glass spheres, steel spheres, and golf balls. Experiments show that a sphere moving over a rough incline with negligible fluid drag in air can reach a constant translation velocity. This constant velocity was found to be proportional to the bed inclination (between 11 ^circ and 21^circ) and the square root of the sphere's diameter, but seemingly independent of the sphere's specific gravity. Two empirical coefficients in the theoretical expression of the sphere's translation velocity were determined by experiments. The collision and friction parts of the shear stress exerted on the interface between the moving sphere and rough incline were determined. The ratio of collision to friction parts appears to increase with increase in the bed inclination. These two parts seem to be of the same order of magnitude. The rolling resistances and the relations between the drag coefficient and Reynolds number for a sphere moving over smooth and rough inclines in a liquid, such as water or salad oil, were determined by a regression analysis based on experimental data. It was found that the drag coefficient for a sphere over the rough incline is larger than that for a sphere over the smooth incline, and both of which are much larger than that for a sphere in free

  14. Management of impacted incisors following surgery to remove obstacles to eruption: a prospective clinical trial.

    Science.gov (United States)

    Pavoni, Chiara; Franchi, Lorenzo; Laganà, Giuseppina; Baccetti, Tiziano; Cozza, Paola

    2013-01-01

    The purpose of this study was to assess the effectiveness of rapid maxillary expansion (RME) vs simply monitoring the eruption of permanent maxillary incisors following the surgical removal of obstacles to their eruption (supernumerary teeth, odontomas). Following surgical removal of the obstacles to incisor eruption (T1), 62 patients were randomly assigned to either the group to undergo RME (34 subjects; mean age 8 years, 11 months ± 11 months) or the group that was monitored without further treatment (28 subjects; mean age=9 years, 1 month ± 1 year). At T2 (1 year after T1), the prevalence rate of erupted incisors was recorded. Also, the time of eruption of the incisors and the amount of space loss were analyzed. At T2, eruption of impacted incisors occurred in approximately 82 percent of the RME group cases vs approximately 39 percent of the monitored group cases (chi-square=10.43, P<.001). Time of eruption was significantly faster in the RME group, and anterior space loss significantly smaller. Rapid maxillary expansion treatment following surgical removal of the obstacles to the eruption of permanent maxillary incisors appears to be an efficient interceptive approach leading to eruption of the incisors in four out of five cases within seven months.

  15. Enamel-free teeth: Tbx1 deletion affects amelogenesis in rodent incisors.

    Science.gov (United States)

    Catón, Javier; Luder, Hans-Ulrich; Zoupa, Maria; Bradman, Matthew; Bluteau, Gilles; Tucker, Abigail S; Klein, Ophir; Mitsiadis, Thimios A

    2009-04-15

    TBX1 is a principal candidate gene for DiGeorge syndrome, a developmental anomaly that affects the heart, thymus, parathyroid, face, and teeth. A mouse model carrying a deletion in a functional region of the Tbx1 gene has been extensively used to study anomalies related to this syndrome. We have used the Tbx1 null mouse to understand the tooth phenotype reported in patients afflicted by DiGeorge syndrome. Because of the early lethality of the Tbx1-/- mice, we used long-term culture techniques that allow the unharmed growth of incisors until their full maturity. All cultured incisors of Tbx1-/- mice were hypoplastic and lacked enamel, while thorough histological examinations demonstrated the complete absence of ameloblasts. The absence of enamel is preceded by a decrease in proliferation of the ameloblast precursor cells and a reduction in amelogenin gene expression. The cervical loop area of the incisor, which contains the niche for the epithelial stem cells, was either severely reduced or completely missing in mutant incisors. In contrast, ectopic expression of Tbx1 was observed in incisors from mice with upregulated Fibroblast Growth Factor signalling and was closely linked to ectopic enamel formation and deposition in these incisors. These results demonstrate that Tbx1 is essential for the maintenance of ameloblast progenitor cells in rodent incisors and that its deletion results in the absence of enamel formation.

  16. Fluorescence intensity dependence on the propagation plane inclination

    International Nuclear Information System (INIS)

    Fernandez, J.E.; Rubio, Marcelo; Sanchez, H. J.

    1987-01-01

    An experimental confirmation of the fluorescence intensity behaviour with the inclination of the propagation plane (α angle) was carried out. A special angular sample-holder was developed and set up on our X-ray spectrometer. This sample-holder allows different positions of irradiation of the sample modifying the α angle until the maximum angle (α Μ ) is reached in the limit situation. In this work, this maximum angle was 86 deg and the incidence and take off angles were both 45 deg. The sample-holder and the collimation system were carefully lined up. The fluorescent spectra of three National Bureau of Standards (NBS) standard samples were taken for sixteen different α angle positions. The theoretical scheme for both enhanced fluorescent lines and nonenhanced fluorescent lines was confirmed, i.e. the invariance of the primary intensity with the α angle and the decline of the enhanced fluorescence intensities under the same conditions. This experimental confirmation agrees with theoretical prediction: the vanishing of the secondary fluorescence in the extreme case α = π/2. (Author) [es

  17. Eruption of first permanent incisors and live weight gain in grazing yearling Angora goats.

    Science.gov (United States)

    McGregor, B A; Butler, K L

    2013-05-01

    To investigate the effects of the timing and duration of eruption of the first permanent incisors, live weight, sex and other factors on contemporaneous live weight gain in Angora goats. Goats were previously part of a pen study on the effects of energy intake of Angora does during pregnancy and lactation on kid development. The design was 3 levels of nutrition in mid-pregnancy by 2 levels of postnatal nutrition in 17 randomised blocks. Artificial insemination, ultrasound examination and feeding does in pens enabled accurate conduct of the study. After weaning, goats were grazed in sex groups. Live weight change between 14 and 20 months of age was related to deciduous first incisor loss and permanent first incisor development and other attributes assessed before the study. Live weight change was related to the elapsed time for first permanent incisors to commence eruption and to the length of time for first permanent incisors to erupt. This response was affected by sex. Over summer and autumn, entire males with short eruption intervals gained 2-3 kg more than entire males with long eruption intervals. Females that reached first permanent incisor eruption by mid-summer had a live weight gain of 3 kg more than those that reached the same development 3 months later. Live weight change in yearling Angora goats was associated with the process of first permanent incisor eruption. In females, live weight gain was greater when first permanent incisor eruption was earlier. In males, live weight gain was greater when first permanent incisor eruption was faster. © 2013 The Authors. Australian Veterinary Journal © 2013 Australian Veterinary Association.

  18. Inclined asymmetric librations in exterior resonances

    Science.gov (United States)

    Voyatzis, G.; Tsiganis, K.; Antoniadou, K. I.

    2018-04-01

    Librational motion in Celestial Mechanics is generally associated with the existence of stable resonant configurations and signified by the existence of stable periodic solutions and oscillation of critical (resonant) angles. When such an oscillation takes place around a value different than 0 or π , the libration is called asymmetric. In the context of the planar circular restricted three-body problem, asymmetric librations have been identified for the exterior mean motion resonances (MMRs) 1:2, 1:3, etc., as well as for co-orbital motion (1:1). In exterior MMRs the massless body is the outer one. In this paper, we study asymmetric librations in the three-dimensional space. We employ the computational approach of Markellos (Mon Not R Astron Soc 184:273-281, https://doi.org/10.1093/mnras/184.2.273, 1978) and compute families of asymmetric periodic orbits and their stability. Stable asymmetric periodic orbits are surrounded in phase space by domains of initial conditions which correspond to stable evolution and librating resonant angles. Our computations were focused on the spatial circular restricted three-body model of the Sun-Neptune-TNO system (TNO = trans-Neptunian object). We compare our results with numerical integrations of observed TNOs, which reveal that some of them perform 1:2 resonant, inclined asymmetric librations. For the stable 1:2 TNO librators, we find that their libration seems to be related to the vertically stable planar asymmetric orbits of our model, rather than the three-dimensional ones found in the present study.

  19. Natural Circulation Characteristics of a Symmetric Loop under Inclined Conditions

    Directory of Open Access Journals (Sweden)

    Xingtuan Yang

    2014-01-01

    Full Text Available Natural circulation is an important process for primary loops of some marine integrated reactors. The reactor works under inclined conditions when severe accidents happen to the ship. In this paper, to investigate the characteristics of natural circulation, experiments were conducted in a symmetric loop under the inclined angle of 0~45°. A CFD model was also set up to predict the behaviors of the loop beyond the experimental scope. Total circulation flow rate decreases with the increase of inclined angle. Meanwhile one circulation is depressed while the other is enhanced, and accordingly the disparity between the branch circulations arises and increases with the increase of inclined angle. Circulation only takes place in one branch circuit at large inclined angle. Also based on the CFD model, the influences of flow resistance distribution and loop configuration on natural circulation are predicted. The numerical results show that to design the loop with the configuration of big altitude difference and small width, it is favorable to reduce the influence of inclination; however too small loop width will cause severe reduction of circulation ability at large angle inclination.

  20. Upper canine inclination influences the aesthetics of a smile.

    Science.gov (United States)

    Bothung, C; Fischer, K; Schiffer, H; Springer, I; Wolfart, S

    2015-02-01

    This current study investigated which angle of canine inclination (angle between canine tooth axis (CA-line) and the line between the lateral canthus and the ipsilateral labial angle (EM-line)) is perceived to be most attractive in a smile. The second objective was to determine whether laymen and dental experts share the same opinion. A Q-sort assessment was performed with 48 posed smile photographs to obtain two models of neutral facial attractiveness. Two sets of images (1 male model set, 1 female model set), each containing seven images with incrementally altered canine and posterior teeth inclinations, were generated. The images were ranked for attractiveness by three groups (61 laymen, 59 orthodontists, 60 dentists). The images with 0° inclination, that is CA-line (maxillary canine axis) parallel to EM-line (the line formed by the lateral canthus and the ipsilateral corner of the mouth) (male model set: 54·4%; female model set: 38·9%), or -5° (inward) inclination (male model set: 20%; female model set: 29·4%) were perceived to be most attractive within each set. Images showing inward canine inclinations were regarded to be more attractive than those with outward inclinations. Dental experts and laymen were in accordance with the aesthetics. Smiles were perceived to be most attractive when the upper canine tooth axis was parallel to the EM-line. In reconstructive or orthodontic therapy, it is thus important to incline canines more inwardly than outwardly. © 2014 John Wiley & Sons Ltd.

  1. Analysis of the golden proportion and width/height ratios of maxillary anterior dentition in patients with lateral incisor agenesis.

    Science.gov (United States)

    Pini, Núbia Pavesi; de-Marchi, Luciana Manzotti; Gribel, Bruno Frazão; Ubaldini, Adriana Lemos Mori; Pascotto, Renata Corrêa

    2012-12-01

      The purpose of this study was to assess the presence of the golden proportion (GP) in the facial view tooth-to-tooth width proportion of the six maxillary anterior teeth and to evaluate the width/height (W/H) ratios of the incisors of patients with maxillary lateral incisor (LI) agenesis treated either with implants or orthodontically (by moving canines into the position of the laterals, recontouring them, and placing composite restorations over the repositioned teeth).   Forty-eight patients with LI agenesis were divided into four experimental groups: unilateral recontouring group (N = 10), bilateral recontouring group (BRG, N = 18), unilateral implant group (UIG, N = 10), bilateral implant group (N = 10), and a control group (CG, N = 25) of patients without agenesis. GP ratios were determined on patients' dental casts placed over Levin's grids, whereas W/H ratios were measured directly on the casts and a millimeter ruler to determine these distances. Statistical analysis was performed with Shapiro-Wilk, Kruskal-Wallis, Mann-Whitney, Friedman, and Wilcoxon tests (p mean W/H ratios of the laterals ranged between 0.75 and 0.90.   Although the GP may be a useful diagnostic guide, it was not observed in the majority of esthetic outcomes of patients treated with maxillary LI agenesis in this study. The assessment of the golden proportion and width/height ratio of upper anterior teeth in patients with upper lateral incisor agenesis treated with either implants or tooth re-contouring may assist dentists and patients in deciding the best treatment option based on the peculiarities of each case. © 2012 Wiley Periodicals, Inc.

  2. Combined orthodontic-restorative management of maxillary central incisors lost following traumatic injury: a case report.

    Science.gov (United States)

    Fleming, Padhraig S; Seehra, Jadbinder; Dibiase, Andrew T

    2011-01-01

    A history of traumatic dental injury to the maxillary central incisors during preadolescence or adolescence is common and may result in premature loss. Treatment options include prosthetic implant replacement, autotransplantation, and orthodontic space closure with direct composite recontouring. This case report describes the treatment of an adolescent girl who presented with a crowded Class I malocclusion complicated by a history of trauma to the maxillary central incisors. The treatment plan consisted of orthodontic space closure following loss of both maxillary central incisors and mandibular premolars. This case highlights that orthodontic space closure can be a valuable treatment option in selected Class I crowded and Class II uncrowded malocclusions, producing predictable and efficient results.

  3. Easy and effective technique of preventing incisor flaring during Forsus treatment

    Directory of Open Access Journals (Sweden)

    Siddharth Shashidhar Revankar

    2014-01-01

    Full Text Available Lower incisor flaring is often encountered during Forsus treatment. To prevent this, consolidating the entire mandibular arch by ligature wire and cinching back the mandibular archwire has been recommended. However, lower incisor flaring might still occur due to ligature breakage from friction of the push rods and also cinching back the mandibular archwire might not be possible in few cases due to anatomic limitations. The following article describes an innovative technique to prevent any chances of lower incisor flaring during Forsus treatment in cases where cinching the archwire is not possible due to anatomic limitations. This method is simple, inexpensive, less time consuming and comfortable for the patient.

  4. The orbital inclination of Cygnus XR-1 measured polarimetrically

    International Nuclear Information System (INIS)

    Dolan, J.F.; Tapia, S.

    1989-01-01

    The X-ray binary Cyg XR-1/HDE 226868 was observed polarimetrically over one orbit at three different optical wavelengths. The standard theory of Brown, et al. (1978) is used to derive an orbital inclination i = 62 deg (+5 deg, -37 deg), where the error is the 90-percent-confidence interval derived by the method of Simmons, et al. (1980). The value of the orbital inclination is significantly lower than values based on polarimetric observations. The difference is a result of the observational protocols used. A bias toward larger values of the inclination caused by the tidal distortion of the primary is still found in the present result. The inclination derived corresponds to a mass of the compact component of 6.3 solar masses, above the maximum mass of any degenerate configuration consistent with general relativity except a black hole. 37 refs

  5. Improved efficiency of lifting freight on inclined mine shafts

    Energy Technology Data Exchange (ETDEWEB)

    Molchanov, A A

    1980-01-01

    Design and operating principles are described for a self-propelled inclined lifter with hinged-lever mechanism of forced compression of the drive wheels to the rails. Limit values are defined for the main parameters of the traction device.

  6. Brilliance and flux reduction in imperfect inclined crystals

    International Nuclear Information System (INIS)

    Lee, W.K.; Blasdell, R.C.; Fernandez, P.B.; Macrander, A.T.; Mills, D.M.

    1996-01-01

    The inclined crystal geometry has been suggested as a method of reducing the surface absorbed power density of high-heat-load monochromators for third-generation synchrotron radiation sources. Computer simulations have shown that if the crystals are perfectly aligned and have no strains then the diffraction properties of a pair of inclined crystals are very similar to a pair of conventional flat crystals with only subtle effects differentiating the two configurations. However, if the crystals are strained, these subtle differences in the behavior of inclined crystals can result in large beam divergences causing brilliance and flux losses. This manuscript elaborates on these issues and estimates potential brilliance and flux losses from strained inclined crystals at the APS

  7. Flame spread over inclined electrical wires with AC electric fields

    KAUST Repository

    Lim, Seung J.; Park, Sun H.; Park, Jeong; Fujita, Osamu; Keel, Sang I.; Chung, Suk-Ho

    2017-01-01

    Flame spread over polyethylene-insulated electrical wires was studied experimentally with applied alternating current (AC) by varying the inclination angle (θ), applied voltage (VAC), and frequency (fAC). For the baseline case with no electric field

  8. A boy with a cleft lip and palate, tritubercular incisors, and finger anomaly

    NARCIS (Netherlands)

    Hennekam, R. C.; van der Horst, C. M.

    1996-01-01

    A boy is described with a unilateral cleft lip and palate, maxillary tritubercular incisors, and unilateral radial torsion of his ringfinger. Family history was uninformative. We have been unable to find a similar case in the literature

  9. Orthodontic management of excessive incisor display of an adult bilateral cleft lip and palate patient

    Directory of Open Access Journals (Sweden)

    Om Prakash Kharbanda

    2016-01-01

    Full Text Available This report entails successful orthodontic treatment of a case of postsurgical malocclusion, short upper lip, and excessive incisor display in an adult patient with bilateral cleft lip and palate. The patient underwent cleft lip repair at an early age of 2 years followed by palatoplasty at the age of 6 years and alveoloplasty at an age of 26 years. He reported with irregular teeth, inability to close lips, excessive visibility of upper incisors associated with short upper lip and difficulty in speech. He was treated with maxillary arch expansion, arch alignment, and intrusion of the incisors followed by prosthetic replacement of the missing right and left lateral incisors. Subsequently, he underwent nose and lip revision surgery at the age of 32 years. The orthodontic procedures and prosthetic rehabilitation have resulted in a near normal dental occlusion with significant improvement in esthetics and psychosocial benefits to the individual. These benefits were further enhanced by nose and lip revision surgery.

  10. Effects of posttreatment skeletal maturity measured with the cervical vertebral maturation method on incisor alignment relapse.

    Science.gov (United States)

    Fudalej, Piotr; Rothe, Laura E; Bollen, Anne-Marie

    2008-08-01

    Our aim was to test the hypothesis that relapse of incisor alignment is associated with skeletal maturity at the end of treatment, as assessed with the cervical vertebral maturation (CVM) method. This was a case-control study with information from the postretention database at the University of Washington. Mandibular incisor irregularity (II) at least 10 years out of retention (T3) was used to define the subjects (II >6 mm, relapse group) and the controls (II 0.05). Pretreatment II and postretention time were found to be correlated with long-term incisor stability (P = 0.007 and 0.034, respectively). Sex was not related to relapse (P = 0.33). Maturity of craniofacial structures at the end of treatment evaluated with the CVM method is not associated with long-term stability of incisor alignment.

  11. Experimental study of critical heat flux in inclined rectangular gap

    International Nuclear Information System (INIS)

    Kim, S.J.; Kim, Y.H.; Noh, S.W.; Suh, K.Y.; Rempe, J.L.; Cheung, F.B.; Kim, S.B.

    2003-01-01

    In the TMI-2 accident, the lower part of the reactor pressure vessel was overheated and then rather rapidly cooled down, as was later found out in a vessel investigation project. This accounted for the possibility of gap cooling feasibility. For this reason, a great deal of investigations was performed to determine the critical heat flux (CHF) from the standpoint of in-vessel retention (IVR). As part of a joint Korean-U.S. International Nuclear Energy Research Initiative (INERI) project, Tests were conducted to examine the critical heat flux (CHF) on the one-dimensional downward heating rectangular channel having a narrow gap by changing the orientation of the copper test heater assembly in a pool of saturated water under the atmospheric pressure. The test parameters include both the gap sizes of 1, 2, 5 and 10 mm, and the surface orientation angles from the downward-facing position (180deg) to the vertical position (90deg), respectively. It was observed that the CHF generally decreases as the surface inclination angle increases and as the gap size decreases. However, in downward-facing position (180deg), somewhat differing results were detected relative to previous reports. For a certain gap size having a similar dimension with vapor layer thickness, more efficient heat transfer was detected and this may be interpreted by characteristic property such as the vapor layer thickness of water. In consistency with several studies reported in the literature, it was found that there exists a transition angle above that the CHF changes with a rapid slope. (author)

  12. Psychosocial Determinants of Romantic Inclination Among Indian Youth

    OpenAIRE

    D. Barani Ganth; S. Kadhiravan

    2017-01-01

    The present study was conducted with the aim of understanding the psychosocial determinants of romantic inclination among youth in India. We involved 779 student participants from a large central university in south India in the age range of 18-24 years. The participants filled measures on romantic inclination, personality, attachment style, interpersonal attraction, and social influence on romantic relationship in addition to a questionnaire on demographic information and relationship histor...

  13. Surgical exposure dan perawatan ortodontik pada impaksi gigi insisif sentral rahang atas (Surgical exposure and orthodontic treatment on labially impacted maxillary central incisor

    Directory of Open Access Journals (Sweden)

    Bingah Fitri Melati

    2014-06-01

    Full Text Available Background: As a clinician we have to concern for an unerupted teeth especially in mixed dentition. Eruption failure can also be caused by early loss of deciduous teeth. Purpose: To report a case of unerupted maxillary central incisor caused by early loss of deciduous teeth due to trauma and the combination of excisional and orthodontic treatment. Case: A 8-years-old girl in mixed dentition phase came to Universitas Airlangga Dental Hospital with chief complaint of unerupted right maxillary central incisor while the left central incisor and both lateral incisor had erupted already. She had trauma when she was 1 year old and loss mostly her primary maxillary central incisors. An intraoral examination revealed lack of space in #11 region with root retained of #51, bulge was palpated in vestibulum and periapical radiograph showed that a delayed eruption upper central incisor without presence of disturbance. Case management: The exposure of the tooth was under local anesthesia a year after the orthodontic performed to make enough space for traction the tooth. A button was placed at palatal and used elastic strait to traction the tooth. After 3 months, bracket placed at labial to positioning until leveled and aligned with adjacent teeth. Conclusion: A simple excisional and orthodontic treatment were succesfully treated the labially impacted teeth.Latar belakang: Sebagai seorang klinisi kita harus memperhatikan apabila terdapat gigi yang belum erupsi terutama pada fase gigi pergantian. Kegagalan erupsi gigi juga dapat disebabkan karena tanggal premature gigi sulung. Tujuan: Melaporkan kasus impaksi gigi insisif sentral rahang atas yang disebabkan kehilangan premature gigi sulung karena trauma dengan kombinasi eksisi sederhana dan perawatan ortodontik. Kasus: Anak perempuan usia 8 tahun pada fase gigi pergantian datang ke Rumah Sakit Gigi dan Mulut Universitas Airlangga dengan keluhan gigi insisif sentral kanan rahang atasnya (#11 belum erupsi meskipun

  14. Treatment of Two Canals in All Mandibular Incisor Teeth in the Same Patient

    Directory of Open Access Journals (Sweden)

    Vandana B. Kokane

    2014-01-01

    Full Text Available The main reason for unfavourable outcome in endodontic treatment of mandibular incisor is the inability to detect the presence of second canal. Pain even after extirpation of complete pulp tissue from root canal of vital teeth is the main indication of hidden canals. The present case report is also on pain because of another neglected canal in all mandibular incisors in the same patient.

  15. Frequency and severity of molar incisor hypomineralization (mih) in a group of mexican children, 2014

    OpenAIRE

    Murrieta Pruneda, José Francisco; Torres Vargas, Jessica; Sánchez Meza, Julieta del Carmen

    2016-01-01

    The frequency of incisor molar hypomineralization is variable, which may be present in up to 25% of the population. Objective. To establish frequency and severity of MIH in a group of Mexican children. Material and Methods. A cross-sectional study was carried out in a convenience sample composed by 433 children between 8 and 12 years old, of both sexes. The survey looked at the clinical examination of the permanent first molars and incisors considering the criteria set by the European Academy...

  16. A Retrospective Analysis of Pre-surgical Incisor Decompensation Attained in an Orthognathic Surgery Population

    Science.gov (United States)

    2016-07-01

    incisors were more proclined. One of the goals of pre - surgical orthodontic treatment is decompensation of the occlusion and movement of teeth into...purpose of this study is to analyze pre - surgical orthodontic incisor decompensation attained in a group of orthognathic surgery patients treated in...the Tri-Service Orthodontic Residency Program. B. Specific Hypothesis Pre - surgical orthodontic treatment does not achieve full decompensation of

  17. Rotational synkineses of occiput and atlas on lateral inclination

    Energy Technology Data Exchange (ETDEWEB)

    Jirout, J.

    1981-02-01

    An X-ray analysis was performed with regard to the question of synkinetic rotational movements of occiput and atlas on lateral inclination of the head and neck. It was found that the frequent synkinetic rotation of the head from the side of inclination can be taken for a stereotype that is ten times more frequent than the rotation towards the side of inclination. However, it does not represent an essential or indispensable feature of the synkinetic reaction. The associated rotation of the atlas from the side of inclination cannot be looked upon as a normal and constant element of the synkinetic response on lateral inclination, as it does not occur in nearly one-half of cases. Moreover, these studies have shown that the rotational movement between occiput and atlas is possible not only in the final stage of maximum forced rotation of the head, but that it belongs to normal dynamic features of the synkinetic response on lateral inclination of the head and neck.

  18. Rotational synkineses of occiput and atlas on lateral inclination

    International Nuclear Information System (INIS)

    Jirout, J.

    1981-01-01

    An X-ray analysis was performed with regard to the question of synkinetic rotational movements of occiput and atlas on lateral inclination of the head and neck. It was found that the frequent synkinetic rotation of the head from the side of inclination can be taken for a stereotype that is ten times more frequent than the rotation towards the side of inclination. However, it does not represent an essential or indispensable feature of the synkinetic reaction. The associated rotation of the atlas from the side of inclination cannot be looked upon as a normal and constant element of the synkinetic response on lateral inclination, as it does not occur in nearly one-half of cases. Moreover, these studies have shown that the rotational movement between occiput and atlas is possible not only in the final stage of maximum forced rotation of the head, but that it belongs to normal dynamic features of the synkinetic response on lateral inclination of the head and neck. (orig.)

  19. TRANSIT TIMING VARIATIONS FOR INCLINED AND RETROGRADE EXOPLANETARY SYSTEMS

    International Nuclear Information System (INIS)

    Payne, Matthew J.; Ford, Eric B.; Veras, Dimitri

    2010-01-01

    We perform numerical calculations of the expected transit timing variations (TTVs) induced on a hot-Jupiter by an Earth-mass perturber. Motivated by the recent discoveries of retrograde transiting planets, we concentrate on an investigation of the effect of varying relative planetary inclinations, up to and including completely retrograde systems. We find that planets in low-order (e.g., 2:1) mean-motion resonances (MMRs) retain approximately constant TTV amplitudes for 0 deg. 170 deg. Systems in higher order MMRs (e.g., 5:1) increase in TTV amplitude as inclinations increase toward 45 deg., becoming approximately constant for 45 deg. 135 deg. Planets away from resonance slowly decrease in TTV amplitude as inclinations increase from 0 deg. to 180 deg., whereas planets adjacent to resonances can exhibit a huge range of variability in TTV amplitude as a function of both eccentricity and inclination. For highly retrograde systems (135 deg. < i ≤ 180 deg.), TTV signals will be undetectable across almost the entirety of parameter space, with the exceptions occurring when the perturber has high eccentricity or is very close to an MMR. This high inclination decrease in TTV amplitude (on and away from resonance) is important for the analysis of the known retrograde and multi-planet transiting systems, as inclination effects need to be considered if TTVs are to be used to exclude the presence of any putative planetary companions: absence of evidence is not evidence of absence.

  20. Thermo-economic performance of inclined solar water distillation systems

    Directory of Open Access Journals (Sweden)

    Agboola Phillips O.

    2015-01-01

    Full Text Available This study investigates the thermo-economic performance of different configurations of inclined solar water desalination for parameters such as daily production, efficiency, system cost and distilled water production cost. The four different configurations considered for this study are as follows; 1. Inclined solar water distillation with bare absorber plate (IISWD with daily production of 5.46 kg/m2 day and daily efficiency of 48.3%. 2. Inclined solar water distillation with wick on absorber plate (IISWDW with daily production of 6.41kg/m2 day and daily efficiency 50.3%. 3. Inclined solar water distillation with wire mesh on absorber plate (IISWDWM with daily production n of 3.03 kg/m2 day and daily efficiency 32.6%. 4. Inclined solar water distillation with bare absorber plate (ISWD. (Control System with daily production of 3.25 kg/m2 day and daily efficiency of 40.1%. The systems potable water cost price ranges from 0.03 $/L for IISWDW to 0.06$/L for IISWDWM System. All the systems are economically and technically feasible as a solar distillation system for potable water in Northern Cyprus. The price of potable water from water vendors/hawkers ranges from 0.11-0.16 $/L. It is more economically viable to have the rooftop inclined solar water desalination system than procuring potable water from vendors.`

  1. Enamel differentiations in Myoxid incisors and their systematic significance

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    Wighart Koenigswald

    1995-05-01

    Full Text Available Abstract Based on enamel microstructure of lower incisors, extant and fossil myoxids can be arranged into three groups. In the first group, Hunter-Schreger bands retain the plesiomorphic state, a transverse orientation. An oblique orientation is found in the second, and in the third group a longitudinal orientation is achieved. This additional morphological character should enter into phylogenetic and systematic discussions. This modification of the schmelzmuster is so far exclusively found in myoxids. Even if parallel evolution within myoxids cannot be excluded, a reversal of the direction of differentiation is most unlikely. Riassunto Differenziazione dello smalto negli incisivi dei Mioxidi e suo significato sistematico - I Mioxidi esistenti e fossili possono essere riuniti in tre gruppi in base alla microstruttura dello smalto degli incisivi inferiori. Nel primo gruppo, le bande Hunter-Schreger mantengono lo stato plesiomorfico, ovvero un orientamento trasversale. L'orientamento è obliquo nel secondo gruppo e longitudinale nel terzo. Questo ulteriore carattere morfologico dovrebbe essere incluso nelle discussioni di sistematica e filogenesi. Questa modificazione del tipo di smalto è stata finora riscontrata solo nei Mioxidi. Anche se non è possibile escludere una evoluzione parallela tra i Mioxidi, una inversione nella direzione di differenziamento è piu improbabile.

  2. Prevalence of molar incisor hypomineralization (MIH) in Singaporean children.

    Science.gov (United States)

    Ng, Jing Jing; Eu, Oy Chu; Nair, Rahul; Hong, Catherine Hsu Ling

    2015-03-01

    There is a lack of data on molar incisor hypomineralization (MIH) in Asia, but this is not an indication that MIH is rare in the Asian population. Early identification of MIH is important as affected teeth frequently display post-eruptive enamel loss which would result in rapid caries progression. This objective of this study was to assess the prevalence of MIH in Singaporean children. Patients were recruited from 30 schools across Singapore. All children were examined by a single dentist, and the judgement criteria used were based on the 2003 European Academy of Paediatric Dentistry criteria. A total of 1083 children; average age of 7.7 ± 0.3 years were examined. One hundred and thirty-five children (12.5%) had MIH. A significantly higher proportion of children of the Malay ethnicity had MIH, compared to Chinese children (P = 0.02). Post-eruptive enamel breakdown and the presence of atypical restorations were correlated with increasing number of MIH teeth/child (Rho= 0.599, P MIH occurrence and that MIH severity may be influenced by the number of MIH teeth/child and the cumulative enamel opacity colour score. © 2014 BSPD, IAPD and John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. Was molar incisor hypomineralisation (MIH) present in archaeological case series?

    Science.gov (United States)

    Kühnisch, Jan; Lauenstein, Anne; Pitchika, Vinay; McGlynn, George; Staskiewicz, Anja; Hickel, Reinhard; Grupe, Gisela

    2016-12-01

    With respect to the unknown aetiology of molar incisor hypomineralisation (MIH), it is unclear whether this phenomenon was overlooked in the last century as a result of a high number of caries in children or if this developmental disorder was not present until then. Therefore, this study determined the presence of MIH in historical dentitions and teeth. Dental remains from late medieval (n = 191, twelfth-sixteenth century, Regensburg, Germany), post-medieval (n = 33, sixteenth-eighteenth century, Passau, Germany) and modern age archaeological skeletal series (n = 99, nineteenth-twentieth century, Altdorf, Germany) were examined for MIH. In addition, linear enamel hypoplasia (LEH), diffuse opacities, hypoplasia and Turner's teeth were documented. MIH-related demarcated opacities or enamel breakdowns were found in only 15 (0.4 %) of the 3891 examined permanent teeth. Ten cases (3.1 %) from a total of 323 dentitions were classified as having MIH. In contrast, 98 individuals (30.3 %) showed LEH. Other enamel disorders were recorded in 64 individuals (19.8 %). With respect to the low number of affected dentitions and teeth, MIH most likely did not exist or was at least rarely present in the investigated archaeological case series. This study supports the hypothesis that MIH may be linked to contemporary living conditions or other health-related factors.

  4. Molar incisor hypomineralization in HIV-infected children and adolescents.

    Science.gov (United States)

    Andrade, Natália Silva; Pontes, Alessandra Silva; de Sousa Paz, Hélvis Enri; de Moura, Marcoeli Silva; Moura, Lúcia de Fátima Almeida de Deus; Lima, Marina de Deus Mourade

    2017-01-01

    The objective was to determine the prevalence of molar incisor hypomineralization (MIH) among individuals between 7 and 15 years old infected or noninfected with human immunodeficiency virus (HIV). The study was conducted with 33 HIV-infected individuals (study group; SG) and 66 non-HIV-infected schoolchildren (control group; CG), paired by gender and age. Data collection was based on medical records (SG), a questionnaire for caregivers and oral examination for diagnosis of MIH (European Academy of Pediatric Dentistry criteria) and caries (DMFT index and ICDAS). Data were analyzed with Mann-Whitney, chi-square, and Fisher's exact tests and logistic regression. In SG, MIH (45.5%) and caries (87.9%) had higher prevalence. MIH was associated with use of protease inhibitors in SG (OR: 2.14; 95% CI: 1.21 to 3.77) and incubator need in CG (OR: 2.80; 95% CI: 1.71 to 9.10). HIV-infected patients had a higher prevalence of MIH and dental caries in the permanent dentition. © 2016 Special Care Dentistry Association and Wiley Periodicals, Inc.

  5. Crown-root morphology of lower incisors in patients with class III malocclusion.

    Science.gov (United States)

    Wang, Bo; Shen, Guofang; Fang, Bing; Zhang, Li

    2012-07-01

    The purpose of this study was to investigate the crown-root morphology of lower incisors in patients with class III malocclusion using cone-beam computed tomography. Cone-beam computed tomography images were analyzed from 53 adult class I patients (group 1), 37 preadolescent class III patients (group 2), and 66 adult class III patients (group 3) comprising 3 divisions (divisions 1, 2, and 3 corresponded to mild, moderate, and severe class III malocclusions). The size and crown-root angulations of lower incisors in different groups and divisions were statistically appraised with group 1 used as the control group. No significant differences were found for the size of lower incisors among different groups and divisions (P > 0.05). Compared with group 1, the crown-root angulations of lower incisors in groups 2 and 3 were significantly larger (P lower incisors of division 3 rather than divisions 2 and 3 exhibited larger crown-root angulations (P lower incisors in class III patients during orthodontic and orthognathic treatment, especially in severe ones.

  6. Dual odontogenic origins develop at the early stage of rat maxillary incisor development.

    Science.gov (United States)

    Kriangkrai, Rungarun; Iseki, Sachiko; Eto, Kazuhiro; Chareonvit, Suconta

    2006-03-01

    Developmental process of rat maxillary incisor has been studied through histological analysis and investigation of tooth-related gene expression patterns at initial tooth development. The tooth-related genes studied here are fibroblast growth factor-8 (Fgf-8), pituitary homeobox gene-2 (Pitx-2), sonic hedgehog (Shh), muscle segment homeobox-1 (Msx-1), paired box-9 (Pax-9) and bone morphogenetic protein-4 (Bmp-4). The genes are expressed in oral epithelium and/or ectomesenchyme at the stage of epithelial thickening to the early bud stage of tooth development. Both the histological observation and tooth-related gene expression patterns during early stage of maxillary incisor development demonstrate that dual odontogenic origins aligned medio-laterally in the medial nasal process develop, subsequently only single functional maxillary incisor dental placode forms. The cascade of tooth-related gene expression patterns in rat maxillary incisor studied here is quite similar to those of the previous studies in mouse mandibular molar, even though the origins of oral epithelium and ectomesenchyme involved in development of maxillary incisor and mandibular molar are different. Thus, we conclude that maxillary incisor and mandibular molar share a similar signaling control of Fgf-8, Pitx-2, Shh, Msx-1, Pax-9 and Bmp-4 genes at the stage of oral epithelial thickening to the early bud stage of tooth development.

  7. Root development of permanent lateral incisor in cleft lip and palate children: A radiographic study

    Directory of Open Access Journals (Sweden)

    Amarlal Deepti

    2007-01-01

    Full Text Available Objective: The objective of this study was to compare the root development of lateral incisor on the cleft side with the root development of its contralateral tooth in cleft lip and palate children. Setting: Cleft lip and palate wing, Meenakshi Ammal Dental College and Hospital, Chennai, South India. Materials and Methods: A sample of 96 orthopantamograms of patients with unilateral or bilateral cleft lip and/or cleft palate was selected, regardless of sex and race. Main Outcome Measure: Orthopantamograms were analyzed for root development of lateral incisor on the cleft and noncleft side. Associated anomalies like hypodontia, supernumerary teeth, malformed lateral incisors and root development of canine, if present, were recorded. Findings and Conclusions: Root development of permanent lateral incisor was delayed on the cleft side compared to the noncleft side. There was a statistically significant relationship between levels of root development of lateral incisors on the cleft side within the different study groups ( P < 0.05. Incidence of hypodontia increased in proportion to cleft severity. Frequency of missing second premolars, supernumerary teeth and malformed lateral incisors increased in cleft lip and palate patients. Root development of canine showed a slight delay on the cleft side when compared to the canine on the noncleft side.

  8. MAXILLARY INCISORS CHANGES DURING SPACE CLOSURE WITH CONVENTIONAL AND SKELETAL ANCHORAGE METHODS: A SYSTEMATIC REVIEW

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    Yasas Shri Nalaka JAYARATNE

    2017-12-01

    Full Text Available Purpose: The objective of this systematic review was to compare the antero-posterior, vertical and angular changes of maxillary incisors with conventional anchorage control techniques and mini-implant based space closure methods. Materials and Methods: The electronic databases Pubmed, Scopus, ISI Web of knowledge, Cochrane Library and Open Grey were searched for potentially eligible studies using a set of predetermined keywords. Full texts meeting the inclusion criteria as well as their references were manually searched. The primary outcome data (linear, angular, and vertical maxillary incisor changes and secondary outcome data (overbite changes, soft tissue changes, biomechanical factors, root resorption and treatment duration were extracted from the selected articles and entered into spreadsheets based on the type of anchorage used. The methodological quality of each study was assessed. Results: Six studies met the inclusion criteria. The amount of incisor retraction was greater with buccally placed mini-implants than conventional anchorage techniques. The incisor retraction with indirect anchorage from palatal mini-implants was less when compared with buccally placed mini-implants. Incisor intrusion occurred with buccal mini-implants, whereas extrusion was seen with conventional anchorage. Limited data on the biomechanical variables or adverse effects such as root resorption were reported in these studies. Conclusion: More RCT’s that take in to account relevant biomechanical variables and employ three-dimensional quantification of tooth movements are required to provide information on incisor changes during space closure.

  9. Maxillary incisors changes during space closure with conventional and skeletal anchorage methods: a systematic review.

    Science.gov (United States)

    Jayaratne, Yasas Shri Nalaka; Uribe, Flavio; Janakiraman, Nandakumar

    2017-01-01

    The objective of this systematic review was to compare the antero-posterior, vertical and angular changes of maxillary incisors with conventional anchorage control techniques and mini-implant based space closure methods. The electronic databases Pubmed, Scopus, ISI Web of knowledge, Cochrane Library and Open Grey were searched for potentially eligible studies using a set of predetermined keywords. Full texts meeting the inclusion criteria as well as their references were manually searched. The primary outcome data (linear, angular, and vertical maxillary incisor changes) and secondary outcome data (overbite changes, soft tissue changes, biomechanical factors, root resorption and treatment duration) were extracted from the selected articles and entered into spreadsheets based on the type of anchorage used. The methodological quality of each study was assessed. Six studies met the inclusion criteria. The amount of incisor retraction was greater with buccally placed mini-implants than conventional anchorage techniques. The incisor retraction with indirect anchorage from palatal mini-implants was less when compared with buccally placed mini-implants. Incisor intrusion occurred with buccal mini-implants, whereas extrusion was seen with conventional anchorage. Limited data on the biomechanical variables or adverse effects such as root resorption were reported in these studies. More RCT's that take in to account relevant biomechanical variables and employ three-dimensional quantification of tooth movements are required to provide information on incisor changes during space closure.

  10. Eruption time of permanent first molars and incisors among female primary school children of riyadh

    International Nuclear Information System (INIS)

    Chohan, A.N.

    2007-01-01

    To determine the mean eruption time of permanent first molars, central and lateral incisors and to compare the relationship of mean eruption time with body mass index (BMI) in Saudi female primary school children from Riyadh, Saudi Arabia. The mean age of children was 89.3 (SD 9.6) months ranging from 71 months to 109 months. The maxillary right first molar had the lowest mean eruption time of 77.4 (SD 3.9) months and the maxillary right lateral incisor was the last tooth to erupt with eruption time of 98.4 (SD 6.5) months. Furthermore, the mandibular incisors erupted significantly earlier than maxillary incisors. By the age of 100 months, 97% of the girls had all their first permanent molars erupted. There was no significant correlation observed between eruption times with BMI of the studied teeth except the maxillary right lateral incisor. However, an inverse relationship may exist between the eruption times and BMI. The Saudi female primary school children showed later eruption time of permanent first molars, central and lateral incisors when compared with the reported results of other national studies. Key words: Eruption time, permanent teeth, Saudi Arabia, female children. (author)

  11. The Role of Epithelial Stat3 in Amelogenesis during Mouse Incisor Renewal.

    Science.gov (United States)

    Zhang, Bin; Meng, Bo; Viloria, Edward; Naveau, Adrien; Ganss, Bernhard; Jheon, Andrew H

    2018-03-16

    The aim of this study was to evaluate the role of epithelial signal transducer and activator of transcription 3 (STAT3) in mouse incisor amelogenesis. Since Stat3 is expressed in the epithelial component of developing and adult mouse teeth, we generated and analyzed Krt14Cre/+;Stat3fl/fl mutant mice in which Stat3 was inactivated in epithelia including ameloblast progenitors and ameloblasts, the cells responsible for enamel formation. Histological analysis showed little enamel matrix in mutant incisors compared to controls. Delayed incisor enamel mineralization was demonstrated using micro-computed X-ray tomography analysis and was supported by an increase in the pre-expression distance of enamel-enriched proteins such as amelogenin, ameloblastin, and kallikrein-4. Lastly, scanning electron microscopy analysis showed little enamel mineralization in mutant incisors underneath the mesial root of the 1st molar; however, the micro-architecture of enamel mineralization was similar in the erupted portion of control and mutant incisors. Taken together, our findings demonstrate for the first time that the absence of epithelial Stat3 in mice leads to delayed incisor amelogenesis. © 2018 S. Karger AG, Basel.

  12. Ion feedback suppression using inclined MCP holes in a 'single-MCP+micromegas+pads' detector

    International Nuclear Information System (INIS)

    Va'vra, J.; Sumiyoshi, T.

    2005-01-01

    We show that the ion backflow to photocathode can be completely suppressed if one uses inclined MCP holes in the presence of a magnetic field. The inclined hole angles are chosen to be aligned with the Lorentz electron angle allowing the electron transmission and amplification, while positive ions, traveling along a different angle, are caught on the MCP hole walls. The detector under investigation is a new gaseous detector structure based on a tandem of two parts, a single MCP (microchannel plate), a micromegas with pad readout. We are aiming to develop a gaseous photon detector with the Bialkali photocathode, however, one could use some ideas in the paper for other types of detectors

  13. Experimental study on pool boiling critical heat flux in inclined confined spaces

    International Nuclear Information System (INIS)

    Wen Qinglong; Chen Jun; Zhao Hua

    2011-01-01

    CHF experiments in confined spaces are performed for near-saturated demineralized water at atmospheric pressure with gap sizes of 3 mm, 5 mm and 8 mm, and inclination angles of 0°, 5°, 10°, 15°, 20°, and 30°. Analysis of CHF data shows that CHF decreases as the inclination angle changes from 300 to full downward facing position (0°) and increases as the gap size varies from 3 mm to 8 mm. In the present study, certain transition angles are also identified for different gap sizes. For the gap sizes of 3 mm, 5 mm and 8 mm, the transition angles are found to be 10°, 15° and 20°, respectively. (authors)

  14. Lower limb joint work and joint work contribution during downhill and uphill walking at different inclinations.

    Science.gov (United States)

    Alexander, Nathalie; Strutzenberger, Gerda; Ameshofer, Lisa Maria; Schwameder, Hermann

    2017-08-16

    Work performance and individual joint contribution to total work are important information for creating training protocols, but were not assessed so far for sloped walking. Therefore, the purpose of this study was to analyze lower limb joint work and joint contribution of the hip, knee and ankle to total lower limb work during sloped walking in a healthy population. Eighteen male participants (27.0±4.7yrs, 1.80±0.05m, 74.5±8.2kg) walked on an instrumented ramp at inclination angles of 0°, ±6°, ±12° and ±18° at 1.1m/s. Kinematic and kinetic data were captured using a motion-capture system (Vicon) and two force plates (AMTI). Joint power curves, joint work (positive, negative, absolute) and each joint's contribution to total lower limb work were analyzed throughout the stance phase using an ANOVA with repeated measures. With increasing inclination positive joint work increased for the ankle and hip joint and in total during uphill walking. Negative joint work increased for each joint and in total work during downhill walking. Absolute work was increased during both uphill (all joints) and downhill (ankle & knee) walking. Knee joint contribution to total negative and absolute work increased during downhill walking while hip and ankle contributions decreased. This study identified, that, when switching from level to a 6° and from 6° to a 12° inclination the gain of individual joint work is more pronounced compared to switching from 12° to an 18° inclination. The results might be used for training recommendations and specific training intervention with respect to sloped walking. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Evaluation of performance of veterinary in-clinic hematology analyzers.

    Science.gov (United States)

    Rishniw, Mark; Pion, Paul D

    2016-12-01

    A previous study provided information regarding the quality of in-clinic veterinary biochemistry testing. However, no similar studies for in-clinic veterinary hematology testing have been conducted. The objective of this study was to assess the quality of hematology testing in veterinary in-clinic laboratories using results obtained from testing 3 levels of canine EDTA blood samples. Clinicians prepared blood samples to achieve measurand concentrations within, below, and above their RIs and evaluated the samples in triplicate using their in-clinic analyzers. Quality was assessed by comparison of calculated total error with quality requirements, determination of sigma metrics, use of a quality goal index, and agreement between in-clinic and reference laboratory instruments. Suitability for statistical quality control was determined using adaptations from the computerized program, EZRules3. Evaluation of 10 veterinary in-clinic hematology analyzers showed that these instruments often fail to meet quality requirements. At least 60% of analyzers reasonably determined RBC, WBC, HCT, and HGB, when assessed by most quality goal criteria; platelets were less reliably measured, with 80% deemed suitable for low platelet counts, but only 30% for high platelet counts, and automated differential leukocyte counts were generally considered unsuitable for clinical use with fewer than 40% of analyzers meeting the least stringent quality goal requirements. Fewer than 50% of analyzers were able to meet requirements for statistical quality control for any measurand. These findings reflect the current status of in-clinic hematology analyzer performance and provide a basis for future evaluations of the quality of veterinary laboratory testing. © 2016 American Society for Veterinary Clinical Pathology.

  16. Stratified flow model for convective condensation in an inclined tube

    International Nuclear Information System (INIS)

    Lips, Stéphane; Meyer, Josua P.

    2012-01-01

    Highlights: ► Convective condensation in an inclined tube is modelled. ► The heat transfer coefficient is the highest for about 20° below the horizontal. ► Capillary forces have a strong effect on the liquid–vapour interface shape. ► A good agreement between the model and the experimental results was observed. - Abstract: Experimental data are reported for condensation of R134a in an 8.38 mm inner diameter smooth tube in inclined orientations with a mass flux of 200 kg/m 2 s. Under these conditions, the flow is stratified and there is an optimum inclination angle, which leads to the highest heat transfer coefficient. There is a need for a model to better understand and predict the flow behaviour. In this paper, the state of the art of existing models of stratified two-phase flows in inclined tubes is presented, whereafter a new mechanistic model is proposed. The liquid–vapour distribution in the tube is determined by taking into account the gravitational and the capillary forces. The comparison between the experimental data and the model prediction showed a good agreement in terms of heat transfer coefficients and pressure drops. The effect of the interface curvature on the heat transfer coefficient has been quantified and has been found to be significant. The optimum inclination angle is due to a balance between an increase of the void fraction and an increase in the falling liquid film thickness when the tube is inclined downwards. The effect of the mass flux and the vapour quality on the optimum inclination angle has also been studied.

  17. Analysis of the inclination method for investigating the pendelloesung interferences of neutron beams and X-rays

    International Nuclear Information System (INIS)

    Belova, N.E.; Somenkov, V.A.; Utemisov, K.; Shilshtein, S.Sh.

    1983-01-01

    Pendelloesung interferences in a wide range of crystal thicknesses and extinction lengths can be measured by the inclination method. The positions of the extrema of intensity coincide well with the calculated ones but the observed contrast of the oscillations is considerably weaker than the theoretical one. A mathematical model is given, taking into account the influence of several factors which characterize the incident radiation as well as the crystal examined. From this follows, that the inclination method is insensitive to many disturbing factors, and therefore it can be used for metrological purposes. (author)

  18. Comparison of interpupillary distance and combined mesiodistal width of maxillary central incisor teeth in two ethnic groups of Northeast India: An in vivo study.

    Science.gov (United States)

    Barman, Jogeswar; Serin, Sangma

    2018-01-01

    Anthropometric measurements of the face can be used as a guide in selecting proper sized anterior teeth. The aim of this study is to evaluate the relationship between the interpupillary distance (IPD) and the combined mesiodistal width of maxillary central incisors (MDW of MCIs) to establish their morphometric criterion and their significance in two ethnic groups of Northeast India. A total of 120 participants consisting of 60 indigenous students each from Assam and Meghalaya in the age group of 18-25 years were selected after taking their written consent. Standardized facial frontal photographs of all the participants were taken using a digital camera in such a manner that maxillary anterior teeth were visible. The photographs were uploaded onto the computer and saved in a file. Anthropometric measurements of IPD and combined MDW of MCIs in centimeters were made using both Adobe Photoshop ® 7.0 software program and manually using a digital vernier caliper on the developed photographs to a same size of 15 cm × 10 cm. Data obtained were tabulated and analyzed using Student "t"-test and Pearson correlation test. The present study reveals a positive correlation with a high degree of statistical significance between IPD and combined mesiodistal width of maxillary central incisors among all the samples irrespective of gender and ethnicity where P < 0.01. IPD can be used as a guide in determining the suitable mesiodistal dimension of the maxillary central incisors.

  19. Delayed orthodontic extrusion of a traumatically intruded immature upper permanent incisor - a case report.

    Science.gov (United States)

    Umesan, Uday Kumar; Chua, Kui Lay; Kok, Ei Chuen

    2014-10-01

    Dental injuries are probably the most common orofacial injuries sustained during sports and play. Intrusion or intrusive luxations occur when the teeth are driven into the alveolus by an axially directed impact. This article describes the clinical case of an 8-year-old patient who suffered complete intrusive luxation of an immature permanent central incisor following an accident. An attempt at spontaneous re-eruption failed to facilitate re-emergence of the tooth beyond 2 mm. The recommended wait-and-see strategy in anticipation of spontaneous re-eruption should cease to be an option when no further elongation can be observed. Orthodontic extrusion or surgical re-positioning is a valid treatment alternative when the former fails. In this case, although the recommended time period for effecting orthodontic extrusion had elapsed, this procedure was undertaken successfully presumably owing to the application of controlled, biologically optimal forces. A review of the extruded tooth a year later revealed no clinical or radiographic signs of loss of vitality. This was confirmed radiographically by the completion of root development, an intact lamina dura and no evident signs of resorption. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  20. Correlation between the distance of maxillary central incisors and incisive papilla in different arch form

    Directory of Open Access Journals (Sweden)

    Nur Ateyya Natasha Mohd Zali

    2018-01-01

    Full Text Available In edentulous treatment, relocation of anterior teeth in the preexisting natural position is the utmost importance. It is necessary to refer to the significant anatomical landmarks, one of them is incisive papilla. To make it more efficient both functionally and biologically, the teeth were arranged in particular geometric manner known as a dental arch. The author has chosen to conducted the research among the Malay race represented by the Malay undergraduate students. The purpose of this study was to evaluate the correlation between the distance of maxillary central incisors and incisive papilla (CI-IP in different arch form and gender. Maxillary impressions of 34 dentate individuals were taken, and the measurements were performed using a digital caliper. The results showed the CI-IP distance was ranging between 7.65 to 9.90 mm, with the average of 8.77 mm. There was no significant difference of the CI-IP distance between male and female regardless of their arch forms (p>0.05. Individuals with ovoid and tapered arch form, however, showed a significant difference of the CI-IP distance between male and female (p0.05. It can be concluded that gender factor was irrelevant towards the CI-IP distance regardless of the individual arch form. However, there was a correlation between the CI-IP distance in different arch forms in both male and female sample.

  1. Model tests and numerical analyses on horizontal impedance functions of inclined single piles embedded in cohesionless soil

    Science.gov (United States)

    Goit, Chandra Shekhar; Saitoh, Masato

    2013-03-01

    Horizontal impedance functions of inclined single piles are measured experimentally for model soil-pile systems with both the effects of local soil nonlinearity and resonant characteristics. Two practical pile inclinations of 5° and 10° in addition to a vertical pile embedded in cohesionless soil and subjected to lateral harmonic pile head loadings for a wide range of frequencies are considered. Results obtained with low-to-high amplitude of lateral loadings on model soil-pile systems encased in a laminar shear box show that the local nonlinearities have a profound impact on the horizontal impedance functions of piles. Horizontal impedance functions of inclined piles are found to be smaller than the vertical pile and the values decrease as the angle of pile inclination increases. Distinct values of horizontal impedance functions are obtained for the `positive' and `negative' cycles of harmonic loadings, leading to asymmetric force-displacement relationships for the inclined piles. Validation of these experimental results is carried out through three-dimensional nonlinear finite element analyses, and the results from the numerical models are in good agreement with the experimental data. Sensitivity analyses conducted on the numerical models suggest that the consideration of local nonlinearity at the vicinity of the soil-pile interface influence the response of the soil-pile systems.

  2. Quantitative analysis of the relationship between maxillary incisors and the incisive canal by cone-beam computed tomography in an adult Japanese population

    Directory of Open Access Journals (Sweden)

    Tomonari Matsumura

    2017-08-01

    Full Text Available Abstract Background In setting goals for orthodontic treatment, determining the morphologies of the alveolar bone and maxillary incisor root is important for avoiding root resorption, dehiscence, and fenestration. This study aimed to analyze the configurational relationships among maxillary incisors, the alveolar border, and the incisive canal by cone-beam computed tomography (CBCT. Methods Cone-beam CT images of 93 orthodontic patients were evaluated for length of the incisive canal (L; angles between the palatal plane and the maxillary alveolar border (θ1, the incisive canal (θ2, and maxillary incisor (θ3; distance from the left maxillary incisor to the incisive canal (D; and cross-sectional areas of the incisive canal (CSAs at three vertical levels. Comparison of variables between male and female patients was performed with the two-sample t test. Correlations between parameters were examined by Pearson’s correlation analysis and Bonferroni correction for multiple comparisons. Results Male patients exhibited significantly greater values of L than female patients. There were significant positive correlations between θ1 and θ2, θ2 and θ3, and θ3 and θ1. While the value of D was the lowest at the oral opening, that of the cross-sectional area of the incisive canal (CSA was the greatest at the incisal root apex. Conclusions This study demonstrated that the incisive canal had large inter-individual variability, and the proximity between the incisive canal and the incisal root could not be precisely predicted by the conventional cephalograms. Therefore, pre-treatment CBCT examination should be recommended when a large amount of maxillary anterior retraction and/or intrusion is planned in orthodontic diagnosis.

  3. Aetiology of molar-incisor hypomineralisation (MIH) in Brazilian children.

    Science.gov (United States)

    Souza, J F; Jeremias, F; Costa-Silva, C M; Santos-Pinto, L; Zuanon, A C C; Cordeiro, R C L

    2013-06-25

    To determine the potential aetiological factors related to molar-incisor hypomineralisation (MIH) in Brazilian children. A total of 1,151 children aged 7-12 years (mean 8.86 ± 1.28), born and living in the urban area of Araraquara, Brazil, were examined by two examiners evaluating the presence of MIH according to criteria suggested by the European Academy of Paediatric Dentistry (2003). Their mothers completed a structured questionnaire about medical history, from pregnancy to the first 3 years of the children's life. Descriptive analyses of data and odds ratios (OR) with 95 % test-based confidence intervals (CI) were estimated. Chi-square test was used to evaluate the differences between groups. The prevalence of MIH in the children was 12.3 %. The interviewing response rate was 90.4 %. The prevalence of miscarriage history (25 vs. 15.4 %; OR = 1.21; 95 % CI 0.30-4.92) and occurrence of anaemia (23 vs. 12.4 %; OR = 2.07; 95 % CI 0.50-8.63) were higher in mothers from MIH group than those from non-MIH group. However, these associations were not statically significant. In the children's medical history, rhinitis, bronchitis (56.5 vs. 52.5 %; OR = 1.17; 95 % CI 0.82-1.68), and high fever (20.4 vs. 18.2 %; OR = 1.14; 0.73-1.76) were more prevalent in MIH group, but there were no significant differences between the groups (p > 0.05). No possible aetiological factor investigated was associated with MIH. Prospective studies are needed to define the aetiological factors involved with MIH.

  4. Molar incisor hypomineralisation: Discernment a group of Iranian Dental Academics

    Directory of Open Access Journals (Sweden)

    Rafat Bagheri

    2014-04-01

    Full Text Available BACKGROUND AND AIM: The objective of the present study was to evaluate the knowledge of a group of Iranian academic dentists regarding incisor hypomineralization (MIH in two dental schools in Iran. METHODS: A survey was undertaken amongst the teaching staff of the dental schools of Shiraz and Tehran Universities of Medical Sciences. The questionnaire consisted of two sections. In the first section respondents were asked to provide socio-demographic information including year and place of receiving, and type of dental qualification. The second section included questions regarding perception and recognition of the MIH defect in their clinical practice, the incidence and severity of the defect (represented by its clinical presentation, their knowledge of its prevalence, possible determinant factors, and their clinical experience with the management strategies for MIH. Data were analyzed using frequency distribution and Pearson's chi-square test for categorical data. The critical level for alpha was set at 0.05. RESULTS: A response rate of 61.3% was achieved. The vast majority of the respondents (85.7% had encountered MIH in their professional work, with 48.8% indicating that yellow-brown opacities were the most prevalent lesion type. A significant difference between specialists was reported in relation to the frequency of observation of MIH (χ2(5 = 15.3; P < 0.001. Resin composite was the most popular material used in treating teeth with MIH (62%. Endodontists (90.0% and pediatric dentists (77.8% used resin composite significantly more than other specialist groups (χ2(5 = 5.8; P < 0.001. Adhesion was the most commonly reported influence on material choice (62.0%. CONCLUSION: MIH is a defect encountered by Iranian dental academic staff with a considerable disparity in knowledge and views regarding its clinical pattern.

  5. Thermal convection of liquid sodium in inclined cylinders

    Science.gov (United States)

    Khalilov, Ruslan; Kolesnichenko, Ilya; Pavlinov, Alexander; Mamykin, Andrey; Shestakov, Alexander; Frick, Peter

    2018-04-01

    The effect of inclination on the low Prandtl number turbulent convection in a cylinder of unit aspect ratio was studied experimentally. The working fluid was sodium (Prandtl number Pr =0.0094 ), the measurements were performed for a fixed Rayleigh number Ra =(1.47 ±0.03 ) ×107 , and the inclination angle varied from β =0∘ (the Rayleigh-Bénard convection, the temperature gradient is vertical) up to β =90∘ (the applied temperature gradient is horizontal) with a step Δ β =10∘ . The effective axial heat flux characterized by the Nusselt number is minimal at β =0∘ and demonstrates a smooth growth with the increase of the cylinder inclination, reaching a maximum at angle β ≈70∘ and decreasing with a further increase of β . The maximal value of the normalized Nusselt number Nu (β )/Nu (0 ) was 1.21. In general, the dependence of Nu (β ) in a cylinder with unit aspect ratio is similar to what was observed in sodium convection in inclined long cylinders but is much weaker. The structure of the flow undergoes a significant transformation with inclination. Under moderate inclination (β ≲30∘ ), the fluctuations are strong and are provided by regular oscillations of large-scale circulation (LSC) and by turbulence. Under large inclination (β >60∘ ), the LSC is regular and the turbulence is weak, while in transient regimes (30∘border of transient and large inclinations. We find the first evidence of strong LSC fluctuations in low Prandtl number convective flow under moderate inclination. The rms azimuthal fluctuations of LSC, about 27∘ at β =0∘ , decrease almost linearly up to β =30∘ , where they are about 9∘. The angular fluctuations in the vicinity of the end faces are much stronger (about 37∘ at β =0∘ ) and weakly decrease up to β =20∘ . The strong anticorrelation of the fluctuations in two halves of the cylinder indicates the torsional character of LSC fluctuations. At β =30∘ , the intensity of the oscillations at the

  6. Determinants of permanent first incisor eruption in grazing Australian Angora goats.

    Science.gov (United States)

    McGregor, B A; Butler, K L

    2011-12-01

    To investigate the effects of live weight, sex and other factors on deciduous (first incisor) loss and permanent first incisor development in Angora goats. Goats were part of a pen study on the effects of energy intake in Angora does during pregnancy and lactation on kid growth and development. The design was three levels of nutrition in mid-pregnancy × two levels of postnatal nutrition in 17 randomised blocks. Conception times were calculated by using artificial insemination, with ultrasound examination 43 days after insemination. Does were fed different amounts of a formulated diet in their pens. After weaning, goats were grazed in sex groups. Deciduous first incisor loss and permanent first incisor development were recorded at 11 time points from 14 to 20 months of age. For each sex, the time for visible eruption and full development of permanent first incisor declined linearly with increased live weight by 5.9 and 5.4 days/kg live weight, respectively. The time to reach similar development stages for first permanent incisors eruption was 3 months longer for the lightest animals compared with the heaviest animals. Date of birth, birth weight, doe age, growth rates, mid-pregnancy and postnatal nutrition, parity, day of weaning and weaning weight had no detectable effect. The results explain much of the substantial range in reported first permanent incisor eruption dates for small ruminants and have application in ageing of goats, marketing of kids for meat, in the selection of animals for breeding flocks and in educational material. © 2011 The Authors. Australian Veterinary Journal © 2011 Australian Veterinary Association.

  7. Chemical and structural composition of Atlantic Canadian moose (Alces alces) incisors with patterns of high breakage

    Energy Technology Data Exchange (ETDEWEB)

    MacKenzie, Cynthia S. Kendall; Clough, Michael J. [Biology Department, Saint Mary' s University, Halifax, Nova Scotia, Canada B3H 3C3 (Canada); Broders, Hugh G., E-mail: hugh.broders@smu.ca [Biology Department, Saint Mary' s University, Halifax, Nova Scotia, Canada B3H 3C3 (Canada); Tubrett, Mike [Inco Innovation Centre, ICP-MS Facility, Memorial University of Newfoundland, P.O. Box 4200, St. John' s, Newfoundland, Canada A1C 5S7 (Canada)

    2011-11-15

    Analysis of mammalian teeth can provide information regarding local environmental conditions. For example, a high incidence of breakage and wear within a population may indicate poor food quality. Individuals consuming a diet causing high mechanical stress on their teeth, and/or lacking the appropriate minerals for proper development, could experience degradation of tooth condition. Previously, we documented a high rate of incisor tooth breakage, with age, in two genetically distinct moose populations in Atlantic Canada. In this study, multi-element ({sup 11}B, {sup 63}Cu, {sup 64}Zn, {sup 75}As, {sup 85}Rb, {sup 88}Sr, {sup 111}Cd, {sup 118}Sn, {sup 137}Ba, {sup 208}Pb, {sup 232}Th, and {sup 238}U) analyses using laser ablation ICP-MS were performed on moose incisors from multiple North American regions. The purpose was to determine whether the elemental composition of moose incisors varies among regions, and whether that variation is related to tooth degradation among Atlantic Canadian populations. A principal components analysis revealed that nearly 50% of the elemental variation in the inner enamel matrix of moose teeth was explained by three groupings of elements. The element groupings revealed differences among geographic regions, but did not explain the variation between incisors that were broken and those that were not. Regression models indicate that the elemental group which includes Cu, Pb, and Zn is related to decreases in incisal integrity. It is likely that other environmental factors contribute to the occurrence of increased incisor breakage in affected populations. The relationship between food resource quantity and quality, as a function of moose density, is hypothesized to explain loss of tooth integrity. - Highlights: {yields} Multi-element analysis of 1300 moose incisors using laser ablation ICP-MS. {yields} Three element groupings explain 50% of tooth composition variation among regions. {yields} Regional differences in tooth composition

  8. Instability timescale for the inclination instability in the solar system

    Science.gov (United States)

    Zderic, Alexander; Madigan, Ann-Marie; Fleisig, Jacob

    2018-04-01

    The gravitational influence of small bodies is often neglected in the study of solar system dynamics. However, this is not always an appropriate assumption. For example, mutual secular torques between low mass particles on eccentric orbits can result in a self-gravity instability (`inclination instability'; Madigan & McCourt 2016). During the instability, inclinations increase exponentially, eccentricities decrease (detachment), and orbits cluster in argument of perihelion. In the solar system, the orbits of the most distant objects show all three of these characteristics (high inclination: Volk & Malhotra (2017), detachment: Delsanti & Jewitt (2006), and argument of perihelion clustering: Trujillo & Sheppard (2014)). The inclination instability is a natural explanation for these phenomena.Unfortunately, full N-body simulations of the solar system are unfeasible (N ≈ O(1012)), and the behavior of the instability depends on N, prohibiting the direct application of lower N simulations. Here we present the instability timescale's functional dependence on N, allowing us to extrapolate our simulation results to that appropriate for the solar system. We show that ~5 MEarth of small icy bodies in the Sedna region is sufficient for the inclination instability to occur in the outer solar system.

  9. The orbital inclination of A0620 - 00 measured polarimetrically

    International Nuclear Information System (INIS)

    Dolan, J.F.; Tapia, S.

    1989-01-01

    The mass of the degenerate primary in A0620 - 00 is inferred from its spectroscopic mass function to be not less than 3.2 solar masses, making it an excellent candidate for a black hole. The exact value of the mass depends on the orbital inclination. The inclination of a binary system can be determined from the shape of its Stokes parameter light curves if the linear polarization of the system varies as a function of orbital phase. A0620 - 00 over one 8-hour binary period was observed with the 4.5-m equivalent MMT. Its polarization in the visible is variable with orbital phase. The standard theory of Brown et al. (1978) was used to derive an orbital inclination of i = 57 deg (+20 deg, -50 deg), where the error is the 90-percent confidence interval. An inclination of i = 57 deg corresponds to a mass of the compact primary of 6.6 solar masses, but the large uncertainty in the measured value of the inclination allows the derived mass of A0620 - 00 to be as low as 3.8 solar masses. If this is taken to be the maximum mass of any degenerate configuration consistent with general relativity except a black hole, then the mass of A0620 - 00 is still not well enough determined to conclude that it must be a black hole. 21 refs

  10. The single-tooth implant treatment of congenitally missing maxillary lateral incisors using angled abutments: A clinical report

    Directory of Open Access Journals (Sweden)

    Suleyman Hakan Tuna

    2009-01-01

    Full Text Available The maxillary lateral incisor is the second most common congenitally absent tooth. There are several treatment options for replacing the missing maxillary lateral incisor, including canine substitution, tooth-supported restoration, or single-tooth implant. Dental implants are an appropriate treatment option for replacing missing maxillary lateral incisor teeth in adolescents when their dental and skeletal development is complete. This case report presents the treatment of a patient with congenitally missing maxillary lateral incisors using dental implants with angled abutments.

  11. Heat transfer coefficient in pool boiling for an electrically heated tube at various inclinations

    International Nuclear Information System (INIS)

    Fahmy, A.S.A.; Mariy, A.H.; Mahmoud, S.I.; Ibrahim, N.A.

    1987-01-01

    An experimental investigation is carried out study the behaviour of heat transfer in pool boiling from a vertical and inclined heated tube at atmospheric pressure. An imperial correlation joining the different parameters affecting the heat transfer coefficient in pool boiling for an electrically heated tube at various inclinations is developed. Two test sections (zircaloy-4 and stainless steel) of 16 n n outer diameter and 120 nm length are investigated. Four levels of heat flux are used for heating the two lest sections (e.g. 381, 518, 721 and 929 k.watt/n 2). The maximum surface temperature achieved is 146.5 degree c for both materials, and the maximum bulk temperature is 95 degree C. It is found that the average heat transfer coefficient is inversely proportional with heated length l, where it reaches a constant value in the horizontal position. The heat transfer coefficient curves at various inclinations with respect to the heated tube length pass around one point which is defined as limit length

  12. On the inclination and habitability of the HD 10180 system

    Energy Technology Data Exchange (ETDEWEB)

    Kane, Stephen R. [Department of Physics and Astronomy, San Francisco State University, 1600 Holloway Avenue, San Francisco, CA 94132 (United States); Gelino, Dawn M., E-mail: skane@sfsu.edu [NASA Exoplanet Science Institute, Caltech, MS 100-22, 770 South Wilson Avenue, Pasadena, CA 91125 (United States)

    2014-09-10

    There are numerous multi-planet systems that have now been detected via a variety of techniques. These systems exhibit a range of both planetary properties and orbital configurations. For those systems without detected planetary transits, a significant unknown factor is the orbital inclination. This produces an uncertainty in the mass of the planets and their related properties, such as atmospheric scale height. Here we investigate the HD 10180 system, which was discovered using the radial velocity technique. We provide a new orbital solution for the system which allows for eccentric orbits for all planets. We show how the inclination of the system affects the mass/radius properties of the planets and how the detection of phase signatures may resolve the inclination ambiguity. We finally evaluate the Habitable Zone properties of the system and show that the g planet spends 100% of an eccentric orbit within the Habitable Zone.

  13. Natural Frequencies and Mode Shapes of Statically Deformed Inclined Risers

    KAUST Repository

    Alfosail, Feras

    2016-10-15

    We investigate numerically the linear vibrations of inclined risers using the Galerkin approach. The riser is modeled as an Euler-Bernoulli beam accounting for the nonlinear mid-plane stretching and self-weight. After solving for the initial deflection of the riser due to self-weight, we use a Galerkin expansion employing 15 axially loaded beam mode shapes to solve the eigenvalue problem of the riser around the static equilibrium configuration. This yields the riser natural frequencies and corresponding exact mode shapes for various values of inclination angles and tension. The obtained results are validated against a boundary-layer analytical solution and are found to be in good agreement. This constitutes a basis to study the nonlinear forced vibrations of inclined risers.

  14. Loading factor and inclination parameter of diagonal type MHD generators

    International Nuclear Information System (INIS)

    Ishikawa, Motoo

    1979-01-01

    Regarding diagonal type MHD generators is studied the relation between the loading factor and inclination parameter which is required for attaining the maximum power density with a given electrical efficiency on the assumption of infinitely segmented electrodes. The average current density on electrodes is calculated against the Hall parameter, loading factor, and inclination parameter. The diagonal type generator is compared with Faraday type generator regarding the average current density. Decreasing the loading factor from inlet to outlet is appropriate to small size generators but increasing to large size generators. The inclination parameter had better decrease in both generators, being smaller for small generators than for large ones. The average current density on electrodes of diagonal type generators varies less with the loading factor than the Faraday type. In large size generators its value can become smaller compared with that of the Faraday type. (author)

  15. Interplay between geometry and temperature for inclined Casimir plates

    International Nuclear Information System (INIS)

    Weber, Alexej; Gies, Holger

    2009-01-01

    We provide further evidence for the nontrivial interplay between geometry and temperature in the Casimir effect. We investigate the temperature dependence of the Casimir force between an inclined semi-infinite plate above an infinite plate in D dimensions using the worldline formalism. Whereas the high-temperature behavior is always found to be linear in T in accordance with dimensional-reduction arguments, different power-law behaviors at small temperatures emerge. Unlike the case of infinite parallel plates, which shows the well-known T D behavior of the force, we find a T D-1 behavior for inclined plates, and a ∼T D-0.3 behavior for the edge effect in the limit where the plates become parallel. The strongest temperature dependence ∼T D-2 occurs for the Casimir torque of inclined plates. Numerical as well as analytical worldline results are presented.

  16. Flow of Dense Granular Suspensions on an Inclined Plane

    Science.gov (United States)

    Bonnoit, C.; Lanuza, J.; Lindner, A.; Clément, E.

    2008-07-01

    We investigate the flow behavior of dense granular suspensions, by the use of an inclined plane. The suspensions are prepared at high packing fractions and consist of spherical non-Brownian particles density matched with the suspending fluid. On the inclined plane, we perform a systematic study of the surface velocity as a function of the layer thickness for various flow rates and tilt angles. We perform measurements on a classical rheometer (parallel-plate rheometer) that is shown to be in good agreement with existing models, up to a volume fraction of 50%. Comparing these results, we show that the flow on an inclined plane can, up to a volume fraction of 50%, indeed be described by a purely viscous model in agreement with the results from classical rheometry.

  17. Dynamic interaction of monowheel inclined vehicle-vibration platform coupled system with quadratic and cubic nonlinearities

    Science.gov (United States)

    Zhou, Shihua; Song, Guiqiu; Sun, Maojun; Ren, Zhaohui; Wen, Bangchun

    2018-01-01

    In order to analyze the nonlinear dynamics and stability of a novel design for the monowheel inclined vehicle-vibration platform coupled system (MIV-VPCS) with intermediate nonlinearity support subjected to a harmonic excitation, a multi-degree of freedom lumped parameter dynamic model taking into account the dynamic interaction of the MIV-VPCS with quadratic and cubic nonlinearities is presented. The dynamical equations of the coupled system are derived by applying the displacement relationship, interaction force relationship at the contact position and Lagrange's equation, which are further discretized into a set of nonlinear ordinary differential equations with coupled terms by Galerkin's truncation. Based on the mathematical model, the coupled multi-body nonlinear dynamics of the vibration system is investigated by numerical method, and the parameters influences of excitation amplitude, mass ratio and inclined angle on the dynamic characteristics are precisely analyzed and discussed by bifurcation diagram, Largest Lyapunov exponent and 3-D frequency spectrum. Depending on different ranges of system parameters, the results show that the different motions and jump discontinuity appear, and the coupled system enters into chaotic behavior through different routes (period-doubling bifurcation, inverse period-doubling bifurcation, saddle-node bifurcation and Hopf bifurcation), which are strongly attributed to the dynamic interaction of the MIV-VPCS. The decreasing excitation amplitude and inclined angle could reduce the higher order bifurcations, and effectively control the complicated nonlinear dynamic behaviors under the perturbation of low rotational speed. The first bifurcation and chaotic motion occur at lower value of inclined angle, and the chaotic behavior lasts for larger intervals with higher rotational speed. The investigation results could provide a better understanding of the nonlinear dynamic behaviors for the dynamic interaction of the MIV-VPCS.

  18. Investigation of Clinical Characteristics and Etiological Factors in Children with Molar Incisor Hypomineralization

    Directory of Open Access Journals (Sweden)

    Maria Rita Giuca

    2018-01-01

    Full Text Available Aim. The purpose of the present study was to evaluate the clinical defects and etiological factors potentially involved in the onset of MIH in a pediatric sample. Methods. 120 children, selected from the university dental clinic, were included: 60 children (25 boys and 35 girls; average age: 9.8 ± 1.8 years with MIH formed the test group and 60 children (27 boys and 33 girls; average age: 10.1 ± 2 years without MIH constituted the control group. Distribution and severity of MIH defects were evaluated, and a questionnaire was used to investigate the etiological variables; chi-square, univariate, and multivariate statistical tests were performed (significance level set at p<0.05. Results. A total of 186 molars and 98 incisors exhibited MIH defects: 55 molars and 75 incisors showed mild defects, 91 molars and 20 incisors had moderate lesions, and 40 molars and 3 incisors showed severe lesions. Univariate and multivariate statistical analysis showed a significant association (p<0.05 between MIH and ear, nose, and throat (ENT disorders and the antibiotics used during pregnancy (0.019. Conclusions. Moderate defects were more frequent in the molars, while mild lesions were more frequent in the incisors. Antibiotics used during pregnancy and ENT may be directly involved in the etiology of MIH in children.

  19. Molar incisor hypomineralization: proportion and severity in primary public school children in Graz, Austria.

    Science.gov (United States)

    Buchgraber, Barbara; Kqiku, Lumnije; Ebeleseder, Kurt A

    2018-03-01

    The aim of this study was to determine the proportion and severity of molar incisor hypomineralization (MIH) in primary school children in Graz (southeast of Austria). In 1111 children aged 6 to 12 years (mean age 9.0 ± 1.2), a wet examination of all teeth was performed by three trained examiners using a dental chair, optimal illumination, a dental mirror, and a dental explorer. All teeth with MIH lesions were registered so that different definitions of MIH were applicable. According to the European Academy of Pediatric Dentistry criteria that were considered valid at the time of the investigation, MIH was diagnosed when at least one first primary molar (FPM) was affected. MIH was present in 78 children (7.0%). In 64 children (5.8%), at least one molar and one incisor were affected (so-called M + IH). Additionally, in 9 children, only incisors were affected. In 7 affected children, teeth other than FPMs and incisors had MIH lesions. Almost an equal number of males (38) and females (40) were affected. The upper and lower molars were equally affected. The upper incisors were more frequently affected than the lower ones. Demarcated enamel opacities were the predominant types of defects. The proportion of MIH was 7.0% in Graz, which is similar to other comparable trials. This study has proven that MIH is an existing dental problem in Graz.

  20. Fluorescence intensity dependence on the propagation plane inclination

    International Nuclear Information System (INIS)

    Fernandez, J.E.; Rubio, Marcelo; Sanchez, H.J.

    1987-01-01

    A Monte Carlo simulation of the primary and secondary X-ray fluorescent emission from an homogeneous and infinite thickness sample, irradiated under different inclination of the propagation plane, is carried out. An agreement with the predictions based on Sherman equations depending on the inclination angle α was found. The invariance of the primary fluorescence with respect to α and the decrease until evanescence of the secondary fluorescence for a α → π/2 are confirmed. A discussion about the physical basis of this dependence is carried out. Similar results are expected for tertiary fluorescence. (Author) [es

  1. Entrepreneurial Inclination Among Business Students: A Malaysian Study

    Directory of Open Access Journals (Sweden)

    Yet-Mee Lim

    2012-10-01

    Full Text Available Entrepreneurship has been the fundamental topics of discussion among the politicians, economists, and academics. Business creation is especially critical in developing countries to stimulate economic growth. The present study attempts to examine entrepreneurial inclination among students who are a potential source of entrepreneurs. The fi ndings of the present research study indicate that majority of our business students are not entrepreneurial-inclined. They do not seem to possess strong entrepreneurial characteristics and entrepreneurial skills, and they are not keen in starting a new business. The roles of higher institutes of education and the government in promoting entrepreneurship are discussed.

  2. Psychopathic Inclination Among Incarcerated Youth of Hazara Division Pakistan

    Directory of Open Access Journals (Sweden)

    Sher Dil

    2016-09-01

    Full Text Available Present study aimed at evaluating the psychopathic inclination among youth and finding the gender differences in psychopathy. An indigenously developed Psychopathy scale (Urdu has been used in this study. Alpha reliability of the scale was .90. The study was conducted on 100 males (50 criminals and 50 non-criminals and 100 females (26 criminals and 74 non-criminals using a convenient sampling technique from three districts of Hazara division: Haripur, Abbottabad, and Mansehra. Results confirmed that there is significant difference in psychopathic inclination of males and females; criminals differed significantly from the non-criminals. The study also paves way for further investigation in the field in Pakistan.

  3. Does Andrews facial analysis predict esthetic sagittal maxillary position?

    Science.gov (United States)

    Resnick, Cory M; Daniels, Kimberly M; Vlahos, Maryann

    2018-04-01

    Cephalometric analyses have limited utility in planning maxillary sagittal position for orthognathic surgery. In Six Elements of Orofacial Harmony, Andrews quantified maxillary position relative to forehead projection and angulation and proposed an ideal relationship. The purpose of this study was to investigate the ability of this technique to predict esthetic sagittal maxillary position. Survey study including a male and female with straight facial profiles, normal maxillary incisor angulations, and Angle's Class I. Maxillary position was modified on lateral photographs to create 5 images for each participant with incisor-goal anterior limit line (GALL) distances of -4, -2, 0, +2, and +4 mm. A series of health care professionals and laypeople were asked to rate each photo in order of attractiveness. A total of 100 complete responses were received. Incisor-GALL distances of +4 mm (41%) and +2 mm (40%) were most commonly considered "most esthetic" for the female volunteer (P < .001). For the male volunteer, there were 2 peak "most esthetic" responses: incisor-GALL distances of 0 mm (37%) and -4 mm (32%) (P < .001). Respondents considered maxillary incisor position 2 to 4 mm anterior to GALL most attractive in a woman and 0 to 4 mm posterior to GALL most esthetic in a man. Using these modified target distances, this analysis may be useful for orthognathic surgery planning. Copyright © 2018 Elsevier Inc. All rights reserved.

  4. Incisor root resorption in class II division 2 patients in relation to orthodontic treatment

    DEFF Research Database (Denmark)

    Faxén Sepanian, Varro; Sonnesen, Liselotte

    2018-01-01

    Background/Objectives: The aims were 1. to analyse differences in the occurrence of orthodontic induced inflammatory root resorption (OIIRR) of the upper and lower incisors in Angle Class II division 2 patients, between patients treated with fixed appliance only (one-phase treatment group......-four subjects treated for Class II division 2 malocclusion were divided into two groups: 46 patients in the one-phase treatment group (28 girls, 18 boys, mean age 14.4) and 28 patients in the two-phase treatment group (18 girls, 10 boys, mean age 12.4) where 336 and 201 incisors were analysed respectively...... group showed significantly more OIIRR for lower central incisors (P = 0.002) compared to the two-phase treatment group. For the both groups combined, boys showed more OIIRR than girls (P = 0.002) and patients with agenesis showed more OIIRR than patients without agenesis (P = 0.019) for the lower...

  5. Dens invaginatus with necrotic pulp in a right maxillary lateral incisor with preserved vitality.

    Science.gov (United States)

    Alessandro, Lanza; Fabrizio, Di Francesco; Gennaro, De Marco; Dario, Di Stasio; Eugenio, Guidetti; Letizia, Perillo; Luigi, Femiano; Felice, Femiano

    2018-01-01

    Dens invaginatus (DI) is a dental malformation occurring in several morphologic types. Consequently, treatment of teeth affected by DI can get complicated because of the complex root canal anatomy. The aim is to describe how to manage a rare report of a DI with necrotic pulp held within the vital pulp of a maxillary lateral incisor. Oral fistula was found on the buccal mucosa of the apex of the vital maxillary lateral incisor with a DI having necrotic pulp. Endodontic treatment of the maxillary lateral incisor and of the tract canal of DI was realized. Clinical disappearance of oral sinus tract was observed after 10 days. On the contrary, the disappearance of radiolucent area occurred after 6 months. A proper and prompt diagnosis is necessary to carry out effective prevention protocols or prevent consequences generating nonrecoverable endo-perio diseases.

  6. Orthodontic Management of a Severely Rotated Maxillary Central Incisor in the Mixed Dentition: A Case Report

    Directory of Open Access Journals (Sweden)

    Arezoo Jahanbin

    2014-06-01

    Full Text Available The aim of this case report was to introduce an appliance for correcting severe rotation of anterior teeth in the mixed dentition period. A 9-year-old Iranian boy with a mixed dentition Class I malocclusion complained of a severely rotated of upper right central incisor. There was a mesiodens between the central incisors. The supernumerary tooth was first extracted and then a Whip appliance which is composed of a removable plate, a cantilever spring and a central bracket on the rotated tooth was utilized. After 8 months, the upper right central incisor was orthodontically brought into proper alignment. Circumferential supracrestal fibrotomy was performed on the overcorrected tooth. One week after surgery, the device was removed and the retention was started. The whip appliance is a removable appliance that can effectively correct severe rotation of anterior teeth especially during the mixed dentition period.

  7. Type II dens evaginatus of maxillary central incisor: An alternative approach

    Directory of Open Access Journals (Sweden)

    Mansour Alrejaie

    2015-01-01

    Full Text Available Dens evaginatus is the developmental anomaly of tooth that exhibits protrusion of a tubercle from occlusal surfaces of premolar, and lingual surfaces of maxillary central incisor and lateral incisors. Dens evaginatus is common in Caucasian population. Saudi Arabia is also well evidenced of such cases. These tubercles have an enamel layer covering dentin core containing a thin extension of pulp. These cusp-like protrusions are susceptible to pulp exposure from wear or fracture because of malocclusion. Type II dens evaginatus involves normal pulp with immature root apex. Materials to enhance the pulpal recession or pulpotomy procedures indicated in such cases require long time and efforts to ensure pulpal recession or root maturity, respectively. Also prolonged treatment has risk of fracture of the cusp and reinfection and requires patient commitment for the follow-up procedures. Present case describes the use of mineral trioxide aggregate (MTA in type II dens evaginatus of maxillary central incisor.

  8. Shovel-shaped incisors and associated invagination in some Asian and African populations.

    Science.gov (United States)

    Kharat, D U; Saini, T S; Mokeem, S

    1990-08-01

    Shovelling of the incisors is considered to be a polygenic inheritable trait. Shovelling differs considerably between groups of racial populations but is relatively stable within each group. Presence or absence of shovelling helps in racial identification and in exploration of ancestry. Periapical radiographs of patients of several nationalities from Asian and African continents were obtained. Shovelling and invaginations associated with the shovel-shaped incisors was studied according to nationality. Results indicated that the incidence of shovelling in Syrians, Jordanians, Palestinians and Filipinos was 5-6 per cent. In Saudi Arabians, Pakistanis and Indians, the incidence of shovelling was 10-12 per cent. Among Yemenis, Sudanese and Egyptians, the incidence of shovelling was 20-25 percent. The occurrence of invaginations in shovel-shaped incisors was 11 per cent.

  9. Fusion of a primary mandibular lateral incisor and canine: A rarity

    Directory of Open Access Journals (Sweden)

    Treville Pereira

    2017-01-01

    Full Text Available Fusion is a developmental anomaly of dental hard tissues characterized by the union of two adjacent teeth. It may be complete with the formation of an abnormally large tooth or incomplete with the union of crowns or roots only. The exact cause is still unknown. This report describes a case of unilateral fusion of the primary lateral incisor and canine in a 6-year-old female patient who accompanied her parents for dental treatment and later had a checkup herself during one of the visits to the dental clinic. Medical history was noncontributory while there was no family history of dental anomalies. An intraoral examination revealed that mandibular right primary lateral incisor was fused to the primary canine. The permanent central incisors were erupting lingually. The intraoral periapical radiograph showed a bifid pulp chamber with a normal-sized root canal. Since the tooth was noncarious, a preventive approach with a periodic follow-up was planned.

  10. Dental anomalies in an orthodontic patient population with maxillary lateral incisor agenesis.

    Science.gov (United States)

    Citak, Mehmet; Cakici, Elif Bahar; Benkli, Yasin Atakan; Cakici, Fatih; Bektas, Bircan; Buyuk, Suleyman Kutalmış

    2016-01-01

    The purpose of this study was to evaluate the prevalence of dental anomalies in a subpopulation of orthodontic patients with agenesis of maxillary lateral incisors (MLI). The material of the present study included the records of the 1964 orthodontic patients. Panoramic radiographs and dental casts were used to analyze other associated eight dental anomalies, including agenesis of other teeth, dens invaginatus, dens evaginatus, peg shaped MLI, taurodontism, pulp stone, root dilaceration and maxillary canine impaction. Out of the 1964 patients examined, 90 were found to have agenesis of MLI, representing a prevalence of 4.6%. The most commonly found associated-anomalies were agenesis of other teeth (23.3%), peg-shaped MLIs (15.6%), taurodontism (42.2%), and dilacerated teeth (18.9%). Permanent tooth agenesis, taurodontism, peg-shaped maxillary lateral incisor, and root dilacerations are frequently associated with maxillary lateral incisor agenesis.

  11. Ras Signaling Regulates Stem Cells and Amelogenesis in the Mouse Incisor.

    Science.gov (United States)

    Zheng, X; Goodwin, A F; Tian, H; Jheon, A H; Klein, O D

    2017-11-01

    The role of Ras signaling during tooth development is poorly understood. Ras proteins-which are activated by many upstream pathways, including receptor tyrosine kinase cascades-signal through multiple effectors, such as the mitogen-activated protein kinase (MAPK) and PI3K pathways. Here, we utilized the mouse incisor as a model to study how the MAPK and PI3K pathways regulate dental epithelial stem cells and amelogenesis. The rodent incisor-which grows continuously throughout the life of the animal due to the presence of epithelial and mesenchymal stem cells-provides a model for the study of ectodermal organ renewal and regeneration. Utilizing models of Ras dysregulation as well as inhibitors of the MAPK and PI3K pathways, we found that MAPK and PI3K regulate dental epithelial stem cell activity, transit-amplifying cell proliferation, and enamel formation in the mouse incisor.

  12. The nose shape as a predictor of maxillary central and lateral incisor width.

    Science.gov (United States)

    Sülün, Tonguç; Ergin, Ugur; Tuncer, Necat

    2005-09-01

    One of the primary aspects of complete denture prosthodontics is determining the correct proportion for the maxillary central incisor width to the lateral incisor width. It has been suggested that the anatomy of the patient's nose is a reliable guide for deciding this ratio. The aim of this study was to test the hypothesis about the relationship between the shape of the nose and the proportion of the central incisor width (CIW) to the lateral incisor width (LIW). The CIW and LIW from a total of 138 subjects (73 males, 65 females) were measured intraorally. The interalar width (IAW) and the width of the root of the nose (WRN) were measured on standard photographs of the subjects. Spearman's rho test was used to analyze the correlation between the proportions of the CIW to the LIW and the IAW to the WRN. The Mann-Whitney Utest was applied to test for any possible gender differences. The IAW, the WRN, and the nose angle (NA) were statistically significantly wider in male subjects than in female subjects. The correlation between IAW/WRN, NA, and CIW/LIW was statistically significant only in female subjects. In the general population, the only statistically significant relationship was between CIW/LIW on the left side and IAW/WRN. Within the results of the IAW, WRN, and NA measurements, we suggest that males have wider, more triangular-shaped noses than females. The proportion of IAW to WRN seems to be a reliable guide for deciding the proportion of the maxillary central incisor width to the lateral incisor.

  13. MEASUREMENTS OF DUST EXTINCTION IN HIGHLY INCLINED SPIRAL GALAXIES

    NARCIS (Netherlands)

    JANSEN, RA; KNAPEN, JH; BECKMAN, JE; PELETIER, RF; HES, R

    1994-01-01

    We study the extinction properties of dust in the well-defined dust lanes of four highly inclined galaxies, using U-, B-, V-, R- and I-band CCD and J- and K'-band near-infrared array images. For three of these galaxies, we could use the symmetry of the underlying light profile to obtain absolute

  14. The effect of circular bridge piers with different inclination angles ...

    Indian Academy of Sciences (India)

    comparing the data obtained from vertical bridge pier and well-known relationships, a relationship ... pier nose, horseshoe vortex, surface vortex wake vortex. ..... After passing several hours and discharging of ..... It is recommended to use this ... Energy. 109–119. [4] Bozkus Z and Yaldiz O 2004 Effects of inclination of bridge.

  15. Reconstruction of Galileo Galilei's Experiment: The Inclined Plane

    Science.gov (United States)

    Straulino, S.

    2008-01-01

    In the "Third Day" of the "Discourses and Mathematical Demonstrations Concerning Two New Sciences" Galileo Galilei describes the famous experiment of the inclined plane and uses it to bring an experimental confirmation to the laws of uniformly accelerated motion. We describe a reconstruction of the experiment and how the results can be used for…

  16. Motion on an Inclined Plane and the Nature of Science

    Science.gov (United States)

    Pendrill, Ann-Marie; Ekström, Peter; Hansson, Lena; Mars, Patrik; Ouattara, Lassana; Ryan, Ulrika

    2014-01-01

    Friction is an important phenomenon in everyday life. All children are familiar with playground slides, which may thus be a good starting point for investigating friction. Motion on an inclined plane is a standard physics example. This paper presents an investigation of friction by a group of 11-year olds. How did they plan their investigations?…

  17. Non-spherical granular flows down inclined chutes

    NARCIS (Netherlands)

    Hidalgo, R.C.; Rubio-Largo, S.M.; Alonso-Marroquin, F.; Weinhart, T.

    2017-01-01

    In this work, we numerically examine the steady-state granular flow of 3D non-spherical particles down an inclined plane. We use a hybrid CPU/GPU implementation of the discrete element method of nonspherical elongated particles. Thus, a systematic study of the system response is performed varying

  18. A layered model for inclined pipe flow of settling slurry

    Czech Academy of Sciences Publication Activity Database

    Matoušek, Václav; Krupička, Jan; Kesely, Mikoláš

    2018-01-01

    Roč. 333, June (2018), s. 317-326 ISSN 0032-5910 R&D Projects: GA ČR GA17-14271S Institutional support: RVO:67985874 Keywords : inclined pipe * settling slurry * pressure drop * flow stratification * laboratory loop Impact factor: 2.942, year: 2016

  19. Students' Entrepreneurial Inclination at a Malaysian Polytechnic: A Preliminary Investigation

    Science.gov (United States)

    Yasin, Ahmad Yasruddin Md; Mahmood, Nik Abdul Aziz Nik; Jaafar, Nik Azyyati Nik

    2011-01-01

    This paper reports preliminary results of an ongoing project to examine students' inclination towards entrepreneurship at a Malaysian polytechnic. The study used a self-administered questionnaire to explore the influence of entrepreneurial intent, perceived behavioral control, self-efficacy, perceived barriers, perceived support factors and…

  20. Rehabilitation of molar-incisor hypomineralization (MIH) complicated with localized tooth surface loss: a case report.

    Science.gov (United States)

    Lam, Walter Y H; Ho, Edward H T; Pow, Edmond H N

    2014-05-01

    Molar-incisor hypomineralization (MIH) is a developmental enamel hypomineralized condition characteristically involving the first permanent molars and sometimes also the incisors. The affected teeth are predisposed to tooth surface loss (TSL) which may not only compromise the esthetics and function but also endanger the pulp and longevity of the teeth. This report describes the management of a patient with MIH complicated with localized TSL and lack of occlusal clearance due to dentoalveolar compensation. The atypical TSL pattern involved all anterior teeth and required the placement of Dahl appliances on both arches.

  1. Modified Quad Helix for Correction of Severely Rotated Incisors in Cleft Cases

    Directory of Open Access Journals (Sweden)

    Aneesha Ashok Shetty

    2014-01-01

    Full Text Available Clefts of the lip, alveolus and/or palate are often associated with several dental anomalies, the most common of which are severely rotated maxillary incisors. Patients with such congenital deformities seek orthodontic treatment as early as possible, for an esthetic as well as psychosocial benefit. Here, a new clinical technique is demonstrated for correction of a severely rotated maxillary central incisor which can be carried out in the mixed dentition phase itself, by modifying a commonly used palatal expansion appliance: the quad helix.

  2. Treatment of Class II subdivision malocclusion with congenitally missing upper lateral incisors: A case report

    Directory of Open Access Journals (Sweden)

    Siddharth Mehta

    2014-01-01

    Full Text Available Orthodontic treatment for patients with unilateral or bilateral congenitally missing lateral incisor poses a challenge mainly with regard to treatment planning. The use of a diagnostic setup is one of the most important aids in the decision-making process. Two alternatives, orthodontic space closure or space opening for prosthetic replacement exist. The present case report shows use of the microimplant for unilateral upper molar distalization and space closure in a Class-II division 1 subdivision malocclusion case with bilateral congenitally missing upper lateral incisors.

  3. Simulating certain aspects of hypogravity: Effects on the mandibular incisors of suspended rats (PULEH model)

    Science.gov (United States)

    Simmons, D. J.; Winter, F.; Morey-Holton, E. R.

    1984-01-01

    The effect of a hypogravity simulating model on the rate of mandibular incisor formation, dentinogenesis and, amelogenesis in laboratory rats was studied. The model is the partial unloading by elevating the hindquarters. In this system, rat hindquarters are elevated 30 to 40 deg from the cage floors to completely unload the hindlimbs, but the animals are free to move about using their forelimbs. This model replicates the fluid sift changes which occur during the weightlessness of spaceflight and produces an osteopenia in the weight bearing skeletons. The histogenesis and/or mineralization rates of the mandibular incisor during the first 19d of PULEH in young growing rats are recorded.

  4. Treating dental crowding with mandibular incisor extraction in an Angle Class I patient

    Directory of Open Access Journals (Sweden)

    Gislana Braga Machado

    2015-06-01

    Full Text Available Mandibular dental crowding often encourages patients to seek orthodontic treatment. The orthodontist should decide between protrusion of incisors or decrease in dental volume so as to achieve proper alignment and leveling. The present study reports the treatment of an Angle Class I malocclusion adolescent female brachyfacial patient with severe mandibular dental crowding, increased curve of Spee and deep overbite. The patient was treated with extraction of a mandibular incisor. This case was presented to the Brazilian Board of Orthodontics and Dentofacial Orthopedics (BBO as a requirement for the title of certified by the BBO.

  5. Maxillary lateral incisors with two canals and two separate curved roots

    Directory of Open Access Journals (Sweden)

    Ajit George Mohan

    2012-01-01

    Full Text Available Variation in the roots and root canal anatomy seems to be the norm rather than an exception. For a successful endodontic treatment, a clinician should have a thorough knowledge of the internal and external dental anatomy and its variations. Maxillary lateral incisors usually exhibit single canal with a single root. In this case, clinical examination and radiographs clearly demonstrates the presence of two root canals with two separate curved roots. This case report emphasizes the need for attention during endodontic management of maxillary lateral incisors.

  6. Differences between dentitions with palatally and labially located maxillary canines observed in incisor width, dental morphology and space conditions

    DEFF Research Database (Denmark)

    Artmann, L; Larsen, H J; Sørensen, H B

    2010-01-01

    To analyze the interrelationship between incisor width, deviations in the dentition and available space in the dental arch in palatally and labially located maxillary ectopic canine cases.......To analyze the interrelationship between incisor width, deviations in the dentition and available space in the dental arch in palatally and labially located maxillary ectopic canine cases....

  7. Molar-incisor-hypomineralisation (MIH). Retrospective clinical study in Greek children. I. Prevalence and defect characteristics.

    Science.gov (United States)

    Lygidakis, N A; Dimou, G; Briseniou, E

    2008-12-01

    This was to evaluate the prevalence and the clinical characteristics of MIH in a group of Greek children. During the years 2003--2005, all MIH cases diagnosed according to the recently set criteria were selected from the new patients clinic of a Community Dental Centre for Children (Athens). Age, gender and teeth involved were recorded. The severity of MIH was determined collectively by dividing the affected teeth in two groups; a) mild defect (demarcated opacities) and b) moderate/severe defect (enamel breakdown and atypical restorations). Evaluation of the distribution of the affected teeth within MIH cases was performed in a separate group of 225 affected children aged 8-12 years with their entire 12 'index' teeth erupted. From the 3,518, 5.5 to 12 year old children that were examined, there were 360 (10.2%) children with MIH, 211 (58.6%) females and 149 (41.4%) males, with 1,926 affected teeth, 1,231 molars and 695 incisors. In the molars group, maxillary molars were more frequently affected (87.8/90.3%) than mandibular (81.7/82.2%). In the central incisor group, maxillary teeth were also more frequently affected (50/55%) than mandibular (24.4/25%), while laterals were the least affected. In all there were 37.9% molars with moderate/severe defects as compared with 4.9% incisors, the remaining 62.1% and 95.1% respectively being mild. The various associations between the affected teeth were evaluated in the sub-group of 225 MIH children with all 'index' teeth erupted (1,286 affected teeth, 776 molars and 510 incisors), with mean number of affected teeth per child being 5.7; separately for molars 3.4 and for incisors 2.2. In these cases 28.4% of the children had only molars affected and 71.6% had both molars and incisors. In descending order the associations of affected teeth more frequently found were: 4 molars/2 incisors (23.5%), 4 molars/4 incisors (16.8%), 4 molars alone (15.1%) and 2 molars alone (9.7%), the remaining being much less. As age increased the

  8. Autotransplantation of a Supernumerary Tooth to Replace a Misaligned Incisor with Abnormal Dimensions and Morphology: 2-Year Follow-Up

    Directory of Open Access Journals (Sweden)

    R. Ebru Tirali

    2013-01-01

    Full Text Available Autotransplantation is a viable treatment option to restore esthetics and function impaired by abnormally shaped teeth when a suitable donors tooth is available. This paper describes the autotransplantation and 2-year follow-up of a supernumerary maxillary incisor as a replacement to a misaligned maxillary incisor with abnormal crown morphology and size. The supernumerary incisor was immediately autotransplanted into the extraction site of the large incisor and was stabilized with a bonded semirigid splint for 2 weeks. Fixed orthodontic therapy was initiated 3 months after autotransplantation. Ideal alignment of the incisors was accomplished after 6 months along with radiographic evidence of apical closure and osseous/periodontal regeneration. In autogenous tooth transplantation, a successful clinical outcome can be achieved if the cases are selected and treated properly.

  9. Molar incisor hypomineralisation (MIH): correlation with dental caries and dental fear.

    Science.gov (United States)

    Kosma, I; Kevrekidou, A; Boka, V; Arapostathis, K; Kotsanos, N

    2016-04-01

    This cross-sectional study was to investigate correlations between molar incisor hypomineralisation (MIH), dental caries and child dental fear. The subjects in the study were representative samples of 8 and 14 year old children from three Greek cities (total N = 2335). Dental examinations were performed by one calibrated examiner in classrooms, after the children had brushed their teeth, using an intraoral mirror and artificial room light supplemented by a penlight. All the children completed the children's fear survey schedule-dental subscale (CFSS-DS) questionnaire. MIH scores were recorded using EAPD criteria and dental caries experience by DMFS/dmfs index. Data were analysed with the Chi-squared (χ (2)), Mann-Whitney and Spearman's rank correlation coefficient tests. The mean DMFS in children with MIH (8-year olds: 1.60 ± 2.01, 14-year olds: 4.60 ± 4.41) was statistically significantly higher than children without MIH (8-year olds: 1.01 ± 1.78, 14-year olds: 3.46 ± 4.28) (p MIH had statistically significantly higher mean DMFS scores than children with mild or no MIH (p MIH status (p = 0.332). Caries experience was associated with the MIH status of the first permanent molars in both age groups (p MIH (26.5 ± 9.6) (p = 0.339), regardless of MIH severity. A positive association between MIH and dental caries was confirmed and a lack of association found between MIH and dental fear in Greek children.

  10. Gender differences in the form of maxillary central incisors analyzed using AutoCAD software.

    Science.gov (United States)

    Brunetto, Juliana; Becker, Mirian Marly; Volpato, Claudia A Maziero

    2011-08-01

    Female teeth are considered more rounded and male teeth more quadrangular. Although lacking in scientific support, this theory helps in selecting the mold of artificial teeth for dentures. Parameters that are more reliable are sought to determine gender differences in tooth form. The purpose of this study was to assess possible differences between genders in terms of tooth form: oval, triangular, or quadrangular. The sample comprised 433 subjects with a mean age of 15 years selected from a population of Brazilian high school students. The maxillary right central incisor (MCI) of each subject was photographed. The images were adjusted to standardize the long axis of the tooth in the vertical position. The AutoCAD computer program was used to analyze graphically the geometric form of the tooth. According to analysis results, form was classified as oval, triangular, or quadrangular. Intraexaminer consistency was analyzed by using linear correlation coefficient and Bland Altman analysis. The relationship between gender and tooth form was analyzed by chi-square and linear regression (α=.05). In women, the form was 57.73% (n=127) oval, 23.54% (n=52) triangular, and 18.64% (n=41) quadrangular; while in men, the form was 54.93% (n=117) oval, 36.15% (n=77) triangular, and 8.92% (n=19) quadrangular (P<.001). The oval form was the most prevalent in both genders. However, the triangular form was more common in men than in women, and the quadrangular form more frequent in women than in men. Copyright © 2011 The Editorial Council of the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.

  11. Magnetic inclination from Brazilian bricks and application to Archeomagnetic dating

    Science.gov (United States)

    Begnini, G. S.; Hartmann, G. A.; Trindade, R. I.

    2013-05-01

    The Earth's magnetic field (EMF) is recorded in archeological baked materials carrying a stable remanent magnetization. This magnetic record can be used for indirectly date the archeological material by comparison with "reference curves" of the EMF. In this work we present magnetic inclination data from two different sites in southeastern Brazil, an ancient and a modern one: (a) a sampling at the ancient sugarcane mill Engenho Central de Piracicaba (ECP, 1881-1974 AD), and (b) a controlled survey at the modern brickyard Olaria Schiavolin (OS). Both of them are located in the city of Piracicaba, São Paulo State, Brazil. Magnetic measurements included stepwise thermal and alternating field demagnetization, anisotropy of magnetic susceptibility (AMS) and low-field magnetic susceptibility vs. temperature. In OS, we collected 40 oriented bricks from 5 sampling points inside the brickyard oven in order to test the stability and reliability of their remanent magnetizations by comparing them with the local field (measured directly with a fluxgate magnetometer). We observed differences of +/- 3° between the local field and the IGRF. When magnetic inclinations are reported relative to the flat planes of the brick (the situation we face for real ancient bricks), the differences due to inclination of the burning plane and magnetic anomalies inside the oven never exceed 6°. These differences are averaged out by using a minimum of 6 bricks (~24 specimens) per sampling point to compute the inclination. In the ancient site ECP we collected 140 non-oriented bricks from 14 different walls; three of them were previously dated using historical records. Inclinations were defined using at least 6 bricks per wall, showing consistent average values within the same walls. When compared to the IGRF and GUFM1 models, the inclinations obtained for the dated walls agreed within the experimental error. We have then applied the same procedure to estimate the age of the remaining walls. Using

  12. Interim Restorative Approach for the Management of Congenitally Missing Permanent Mandibular Incisors: Presentation of Three Cases

    Directory of Open Access Journals (Sweden)

    Prashanth Prakash

    2011-01-01

    Full Text Available Congenital missing of mandibular permanent incisors with retained primary incisors may jeopardize the esthetic appearance and psychological development of children, especially during the years of transition into adolescence. The retained primary teeth are necessary for the maintenance and normal development of alveolar bone, which in turn is essential for future definitive rehabilitation. In such situations, an interim restoration may be provided before any definitive treatment is given to comfort the young patient during this transition period. Interim restorations may include resin-modified additions to the existing teeth as well as more sophisticated restorations such as resin-retained bridge and removable partial dentures. However, this restoration differs for different clinical situations based on various factors such as age and patient compliance, and also consideration has to be given for the growth changes of the child. The aim of this present paper is to discuss the esthetic management of three cases with bilateral agenesis of permanent mandibular incisors and retained primary incisors with composite interim restoration.

  13. Endocrine and anatomical findings in a case of Solitary Median Maxillary Central Incisor Syndrome

    NARCIS (Netherlands)

    Szakszon, Katalin; Felszeghy, Enikő; Csízy, István; Józsa, Tamás; Káposzta, Rita; Balogh, Erzsébet; Oláh, Eva; Balogh, István; Berényi, Ervin; Knegt, Alida C.; Ilyés, István

    2012-01-01

    Solitary Median Maxillary Central Incisor Syndrome (SMMCI) is a rare malformation syndrome consisting of multiple, mainly midline defects. Some authors suggest that it is a mild manifestation of the wide spectrum of holoprosencephaly, others classify it rather as a distinct entity. Authors report a

  14. Prevalence of molar-incisor-hypomineralisation among children participating in the Dutch National Epidemiological Survey

    NARCIS (Netherlands)

    Jasulaityte, L.; Weerheijm, K.L.; Veerkamp, J.S.

    2008-01-01

    Aim: This was to determine the prevalence of Molar-Incisor- Hypomineralisation (MIH) among children participating in the Dutch National Epidemiological Survey of 2003 and to compare the prevalence data with that found in the previous survey of 1999 when MIH was found in 9.7% of 11-year-old Dutch

  15. Investigation of Clinical Characteristics and Etiological Factors in Children with Molar Incisor Hypomineralization

    Science.gov (United States)

    Giuca, Maria Rita; Cappè, Maria; Carli, Elisabetta; Lardani, Lisa

    2018-01-01

    Aim The purpose of the present study was to evaluate the clinical defects and etiological factors potentially involved in the onset of MIH in a pediatric sample. Methods 120 children, selected from the university dental clinic, were included: 60 children (25 boys and 35 girls; average age: 9.8 ± 1.8 years) with MIH formed the test group and 60 children (27 boys and 33 girls; average age: 10.1 ± 2 years) without MIH constituted the control group. Distribution and severity of MIH defects were evaluated, and a questionnaire was used to investigate the etiological variables; chi-square, univariate, and multivariate statistical tests were performed (significance level set at p MIH defects: 55 molars and 75 incisors showed mild defects, 91 molars and 20 incisors had moderate lesions, and 40 molars and 3 incisors showed severe lesions. Univariate and multivariate statistical analysis showed a significant association (p MIH and ear, nose, and throat (ENT) disorders and the antibiotics used during pregnancy (0.019). Conclusions Moderate defects were more frequent in the molars, while mild lesions were more frequent in the incisors. Antibiotics used during pregnancy and ENT may be directly involved in the etiology of MIH in children. PMID:29861729

  16. Excess NF-kB induces ectopic odontogenesis in embryonic incisor epithelium

    Czech Academy of Sciences Publication Activity Database

    Blackburn, J.; Kawasaki, K.; Porntaveetus, T.; Kawasaki, M.; Otsuka-Tanaka, Y.; Miake, Y.; Ota, M. S.; Watanabe, M.; Hishinuma, M.; Nomoto, T.; Oommen, S.; Ghafoor, S.; Harada, F.; Nozawa-Inoue, K.; Maeda, T.; Peterková, Renata; Lesot, H.; Inoue, J.; Akiyama, T.; Schmidt-Ulrich, R.; Liu, B.; Hu, Y.; Page, A.; Ramírez, Á.; Sharpe, P. T.; Ohazama, A.

    2015-01-01

    Roč. 94, č. 1 (2015), s. 121-128 ISSN 0022-0345 R&D Projects: GA ČR GB14-37368G Institutional support: RVO:68378041 Keywords : incisor * tooth development Subject RIV: EA - Cell Biology Impact factor: 4.602, year: 2015

  17. A study of the management of 55 traumatically intruded permanent incisor teeth in children.

    LENUS (Irish Health Repository)

    Stewart, C

    2009-01-01

    These were to examine the main presenting, treatment and outcome factors for intruded permanent incisors in children, the effect of apical development and degree of intrusion on decisions on repositioning, the effect of apical development status on the maintenance of pulp vitality and the time of pulp extirpation and to compare the decisions made to the advice given in existing clinical guidelines.

  18. “Maxillary lateral incisor partial anodontia sequence”: a clinical entity with epigenetic origin

    Science.gov (United States)

    Consolaro, Alberto; Cardoso, Maurício Almeida; Consolaro, Renata Bianco

    2017-01-01

    ABSTRACT The relationship between maxillary lateral incisor anodontia and the palatal displacement of unerupted maxillary canines cannot be considered as a multiple tooth abnormality with defined genetic etiology in order to be regarded as a “syndrome”. Neither were the involved genes identified and located in the human genome, nor was it presumed on which chromosome the responsible gene would be located. The palatal maxillary canine displacement in cases of partial anodontia of the maxillary lateral incisor is potentially associated with environmental changes caused by its absence in its place of formation and eruption, which would characterize an epigenetic etiology. The lack of the maxillary lateral incisor in the canine region means removing one of the reference guides for the eruptive trajectory of the maxillary canine, which would therefore, not erupt and /or impact on the palate. Consequently, and in sequence, it would lead to malocclusion, maxillary atresia, transposition, prolonged retention of the deciduous canine and resorption in the neighboring teeth. Thus, we can say that we are dealing with a set of anomalies and multiple sequential changes known as sequential development anomalies or, simply, sequence. Once the epigenetics and sequential condition is accepted for this clinical picture, it could be called “Maxillary Lateral Incisor Partial Anodontia Sequence.” PMID:29364376

  19. ASSESSMENT OF ROOT RESORPTION DEGREE OF INCISORS AFTER ORTHODONTIC TREATMENT IN ADULTS

    Directory of Open Access Journals (Sweden)

    I. Luchian

    2012-03-01

    Full Text Available The main iatrogenic effects associated with orthodontic treatment refer to: influence of orthodontic rings on the periodontal tissue; gum retractions; the effect of the orthodontic treatment on dental root (root resorption; the effect of the orthodontic treatment on alveolar bone height; mobility and pain associated with orthodontic treatment. AIM of the study: To assess the degree of root resorption of incisors, after orthodontic treatment, on a group of 48 adults with dental-maxillary abnormalities. Materials and method: The study included 48 young adult patients, 35 women and 13 men aged 18 to 30 years, who had received fixed orthodontic treatment. To assess the degree of root resorption (changes at root level and apical contour length, apical radiographies were taken in the maxillary incisors and jaw both at the beginning and end of the orthodontic treatment. Results: Out of the 239 incisors examined at the beginning of orthodontic treatment, 163 showed code 0, meaning 88.1%, and 50 showed a slight squash apex (code 1, respectively 10.9%. Only 1% of all incisors assessed presented mild and severe root resorption. Conclusions: The results of the study show that, generally, an adult orthodontic treatment, applied for functional and aesthetic objectives, may have clinically acceptable iatrogenic effects.

  20. Impaction of Maxillary Central Incisors: Surgical and Orthodontic Treatment--Case Report.

    Science.gov (United States)

    Knop, Luegya Amorim Henriques; Shintcovsk, Ricardo Lima; Gandini, Luiz Gonzaga; Parsekian, Lidia; Pinto, Ary Santos

    2015-01-01

    The aim of this paper is to report two clinical cases, which was performed with surgical exposure and orthodontic traction of a maxillary central incisors. Light forces were used during the orthodontic treatment applied on rigid wires as anchorage. It was noted that teeth presented adequate clinical crown height and gingival contours.

  1. Fracture resistance of reattached incisor fragments with mini fibre-reinforced composite anchors.

    NARCIS (Netherlands)

    Fennis, W.M.M.; Kreulen, C.M.; Wolke, J.G.C.; Fokkinga, W.A.; Machado, C.; Creugers, N.H.J.

    2009-01-01

    OBJECTIVES: Fractured coronal fragments of incisors can be adhered to the remaining tooth with resin composite, but are prone to failure. This study explores whether mini fibre-reinforced composite (FRC) anchors increase fracture resistance of reattached fragments. METHODS: Forty-five extracted

  2. “Maxillary lateral incisor partial anodontia sequence”: a clinical entity with epigenetic origin

    Directory of Open Access Journals (Sweden)

    Alberto Consolaro

    Full Text Available ABSTRACT The relationship between maxillary lateral incisor anodontia and the palatal displacement of unerupted maxillary canines cannot be considered as a multiple tooth abnormality with defined genetic etiology in order to be regarded as a “syndrome”. Neither were the involved genes identified and located in the human genome, nor was it presumed on which chromosome the responsible gene would be located. The palatal maxillary canine displacement in cases of partial anodontia of the maxillary lateral incisor is potentially associated with environmental changes caused by its absence in its place of formation and eruption, which would characterize an epigenetic etiology. The lack of the maxillary lateral incisor in the canine region means removing one of the reference guides for the eruptive trajectory of the maxillary canine, which would therefore, not erupt and /or impact on the palate. Consequently, and in sequence, it would lead to malocclusion, maxillary atresia, transposition, prolonged retention of the deciduous canine and resorption in the neighboring teeth. Thus, we can say that we are dealing with a set of anomalies and multiple sequential changes known as sequential development anomalies or, simply, sequence. Once the epigenetics and sequential condition is accepted for this clinical picture, it could be called “Maxillary Lateral Incisor Partial Anodontia Sequence.”

  3. Acquired incisor malocclusion in an adult rabbit buck. A case report ...

    African Journals Online (AJOL)

    A diagnosis of acquired incisor malocclusion was made based on the history, physical examination of the rabbit and postmortem examination of the skull. To the best of our knowledge, this appears to be the first reported case of this condition in Nigeria. It is suggested that the condition may be more common among rabbits ...

  4. A comparison of mandibular incisor proclination when using clear aligners and fixed labial orthodontic brackets

    OpenAIRE

    Hennessy, Joe

    2015-01-01

    The objective of this ‘2-arm parallel' clinical trial was to compare the mandibular incisor proclination produced by fixed labial appliances and 3rd generation clear aligners. TARA (Trinity’s Access to Research Archive) has a robust takedown policy. Please contact us if you have any concerns:

  5. Incidence of two canals in extracted mandibular incisors teeth of Saudi Arabian samples

    Directory of Open Access Journals (Sweden)

    Khalid S Al-Fouzan

    2012-01-01

    Full Text Available Aim: The purpose of this in vitro study is to provide clinical data on the presence of the second canal in mandibular incisor teeth of Saudi Arabian Samples. Materials and Methods: Eighty extracted human mandibular incisors were collected from Saudi patients. The teeth were accessed by small round bur then placed in 5.25% sodium hypochlorite for 24 hours to dissolve the organic debris. Indian ink was injected inside the root canal systems under negative pressure. The teeth were decalcified in 5% nitric acid for three days then dehydrated in different concentrations of ethyl alcohol. Following the decalcification process, the teeth were cleared in methyl salicylate and evaluated according to Vertucci′s classification. Result: Fifty six of both mandibular central and lateral incisor teeth (70% had type I canal configuration (one main canal and one main apical foramen, while the remaining 30% of the sample (24 teeth had a type III canal configuration (two separate canals and merged into one canal before exiting the tooth through single apical foramen. Conclusion : The incidence of two canals in mandibular incisor teeth is about one third of the examined Saudi Arabian samples with no difference between the centrals and laterals. The clinician should deal with these teeth as if they have two canals unless it is proved otherwise.

  6. Distribution and structure of dental enamel in incisors of Tabby mice

    Czech Academy of Sciences Publication Activity Database

    Risnes, S.; Peterková, Renata; Lesot, H.

    2005-01-01

    Roč. 50, - (2005), s. 181-184 ISSN 0003-9969 R&D Projects: GA MŠk(CZ) OC B23.002; GA ČR GA304/02/0448 Institutional research plan: CEZ:AV0Z5039906 Keywords : enamel * incisor * mouse Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 1.288, year: 2005

  7. Eruption age of permanent mandibular first molars and central incisors in the south Indian population

    Directory of Open Access Journals (Sweden)

    Gupta Rakhi

    2007-01-01

    Full Text Available Objective: The existing eruption schedules for permanent and deciduous dentition are based on studies in the Western population. Since Indians differ from Westerners racially, genetically, and environmentally, these studies fail to provide relevant guidance on the eruption schedule in the Indian population. This study aims at determining the eruption pattern of permanent mandibular molars and central incisors in the south Indian population. Materials and Methods: 10,156 apparently healthy Indian children in the age-group of 6-9 years were examined with mouth mirror and probe under adequate illumination for the status of the eruption of the permanent mandibular first molar and permanent mandibular central incisor. Pearson′s Chi-square test with Yates′ continuity correction was used to calculate the P -value for comparison of proportion between girls and boys. The values obtained in our study were compared with the standard values. The Z-test with continuity correction was used to calculate the P -value. Results: As per our study, the permanent mandibular first molars and central incisors erupted one to two years later compared to the values reported in Westerners. The earlier eruption of the permanent mandibular first molars compared to the permanent mandibular central incisors, as well as the earlier eruption of both the teeth in girls compared to boys, were in accordance with the existing literature. Conclusion: The eruption age reported by us may form a standard reference for eruption age in Indians.

  8. Direct Resin Composite Restoration of Maxillary Central Incisors with Fractured Tooth Fragment Reattachment: Case Report.

    Science.gov (United States)

    Szmidt, Monika; Górski, Maciej; Barczak, Katarzyna; Buczkowska-Radlińska, Jadwiga

    This article presents a clinical protocol to reconstruct two accidentally damaged maxillary central incisors using composite resin material and a fractured tooth component. A patient was referred to the clinic with fracture of the two maxillary central incisors. Clinical examination revealed that both teeth were fractured in the middle third of the crown and that the fractures involved enamel and dentin with no pulp exposure. The patient had also suffered a lower lip laceration. When the lip was evaluated, a fractured fragment of the maxillary right central incisor was found inside the wound. The missing part of the tooth was replaced via adhesive attachment. Due to the damage of the fractured part of the maxillary left central incisor, direct composite restoration of this tooth was performed. With the advent of adhesive dentistry, the process of fragment reattachment has become simplified and more reliable. This procedure provides improved function, is faster to perform, and provides long-lasting effects, indicating that reattachment of a coronal fragment is a realistic alternative to placement of conventional resin composite restorations.

  9. Changes in root lengths of maxillary incisors during orthodontic retention period

    Directory of Open Access Journals (Sweden)

    Ravanmehr H

    2006-01-01

    Full Text Available Background and Aim: External apical root resorption is a common iatrogenic consequence of orthodontic treatment. Much controversy exists in the literature about changes in root lengths at post treatment periods. Although many practitioners believe that resorption becomes stable after active treatment, quantitative data are scarce. The purpose of this study was to determine quantitative changes in root lengths of maxillary incisors during fixed orthodontic post treatment period, and to assess if it is influenced by gender and factors related to active treatment. Materials and Methods: This was a case cross over study, performed on 80 patients (52 females and 28 males aged between 13 and 22 years. At debonding stage and beginning of retention phase of fixed orthodontic treatment, Hawley type retainer was fabricated for maxillary arch. Periapical radiographs of maxillary incisors using standard parallel technique were obtained immediately after debonding, and 3 and 7 months later. Crown and root lengths of maxillary incisors were measured using computer program. Changes in root lengths were calculated considering correction factors. Also associations between some factors and the change in root lengths during post treatment periods were assessed. These included gender, type of treatment plan (non extraction/extraction, technique (standard edgewise/straight-wire edgewise and duration of active treatment (less than 2 years/2 years and more. T-test and 4-way ANOVA were used for statistical analysis with P0.05 as the limit of significance. Results: No significant relation was found between apical root resorption of maxillary central incisors and time elapsed after treatment. Significant relation was observed between apical root resorption of maxillary lateral incisors and the length of post treatment period. No significant relation was found between root length changes of maxillary incisors during post treatment period and gender, type of treatment

  10. Entrepreneurial Inclination Among Business Students: A Malaysian Study

    Directory of Open Access Journals (Sweden)

    Yet-Mee Lim

    2012-11-01

    Full Text Available Normal 0 false false false IN X-NONE AR-SA MicrosoftInternetExplorer4 Entrepreneurship has been the fundamental topics of discussion among the politicians, economists, and academics. Business creation is especially critical in developing countries to stimulate economic growth. The present study attempts to examine entrepreneurial inclination among students who are a potential source of entrepreneurs. The fi ndings of the present research study indicate that majority of our business students are not entrepreneurial-inclined. They do not seem to possess strong entrepreneurial characteristics and entrepreneurial skills, and they are not keen in starting a new business. The roles of higher institutes of education and the government in promoting entrepreneurship are discussed.

  11. Graphs and matroids weighted in a bounded incline algebra.

    Science.gov (United States)

    Lu, Ling-Xia; Zhang, Bei

    2014-01-01

    Firstly, for a graph weighted in a bounded incline algebra (or called a dioid), a longest path problem (LPP, for short) is presented, which can be considered the uniform approach to the famous shortest path problem, the widest path problem, and the most reliable path problem. The solutions for LPP and related algorithms are given. Secondly, for a matroid weighted in a linear matroid, the maximum independent set problem is studied.

  12. Composition sensitivity of the Auger observatory through inclined showers

    International Nuclear Information System (INIS)

    Ave, M.; Watson, A.A.; Hinton, J.A.; Vazquez, R.A.; Zas, E.

    2003-01-01

    We report a calculation of the expected rate of inclined air showers induced by ultra high-energy cosmic rays to be obtained by the Auger Southern Observatory assuming different mass compositions. We describe some features that can be used to distinguish photons at energies as high as 10 20 eV. The discrimination of photons at such energies will help to test some models of the origin of ultrahigh-energy cosmic rays

  13. Sagittal x-ray beam deviation at asymmetric inclined diffractors

    Czech Academy of Sciences Publication Activity Database

    Korytár, D.; Hrdý, Jaromír; Artemiev, Nikolai; Ferrari, C.; Freund, A.

    2001-01-01

    Roč. 8, - (2001), s. 1136-1139 ISSN 0909-0495 R&D Projects: GA MŠk OK 305; GA MPO PZ-CH/22 Institutional research plan: CEZ:AV0Z1010914 Keywords : x-ray optics * Si(111) W/grooved crystals * inclined diffraction * out-of-diffraction-plane beams * sagittal focusing Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.519, year: 2001

  14. Aqua/Aura Updated Inclination Adjust Maneuver Performance Prediction Model

    Science.gov (United States)

    Boone, Spencer

    2017-01-01

    This presentation will discuss the updated Inclination Adjust Maneuver (IAM) performance prediction model that was developed for Aqua and Aura following the 2017 IAM series. This updated model uses statistical regression methods to identify potential long-term trends in maneuver parameters, yielding improved predictions when re-planning past maneuvers. The presentation has been reviewed and approved by Eric Moyer, ESMO Deputy Project Manager.

  15. Two Mechanisms of Sensorimotor Set Adaptation to Inclined Stance

    Directory of Open Access Journals (Sweden)

    Kyoung-Hyun Lee

    2017-10-01

    Full Text Available Orientation of posture relative to the environment depends on the contributions from the somatosensory, vestibular, and visual systems mixed in varying proportions to produce a sensorimotor set. Here, we probed the sensorimotor set composition using a postural adaptation task in which healthy adults stood on an inclined surface for 3 min. Upon returning to a horizontal surface, participants displayed a range of postural orientations – from an aftereffect that consisted of a large forward postural lean to an upright stance with little or no aftereffect. It has been hypothesized that the post-incline postural change depends on each individual’s sensorimotor set: whether the set was dominated by the somatosensory or vestibular system: Somatosensory dominance would cause the lean aftereffect whereas vestibular dominance should steer stance posture toward upright orientation. We investigated the individuals who displayed somatosensory dominance by manipulating their attention to spatial orientation. We introduced a distraction condition in which subjects concurrently performed a difficult arithmetic subtraction task. This manipulation altered the time course of their post-incline aftereffect. When not distracted, participants returned to upright stance within the 3-min period. However, they continued leaning forward when distracted. These results suggest that the mechanism of sensorimotor set adaptation to inclined stance comprises at least two components. The first component reflects the dominant contribution from the somatosensory system. Since the postural lean was observed among these subjects even when they were not distracted, it suggests that the aftereffect is difficult to overcome. The second component includes a covert attentional component which manifests as the dissipation of the aftereffect and the return of posture to upright orientation.

  16. Inclination of undergraduate medical students towards teaching as career

    OpenAIRE

    Apturkar, D. K.; Dandekar, Usha K.; Dandkar, Kundankumar Narayan; Jorwekar, Golul Jayant; Baviskar, Padmakar Kashinath

    2014-01-01

    Introduction: There is acute shortage of teachers in medical field and very few new members are joining this noble profession. The shortage of medical teachers is resulting in decrease of teaching quality, decrease in number of medical seats and the country is losing its education standard worldwide.Aims: To find out the view and inclination of undergraduate medical students towards teaching as career.Objectives: It is an attempt to find possible reasons preventing or stimulating the undergra...

  17. Characterization and improvement of highly inclined optical sheet microscopy

    Science.gov (United States)

    Vignolini, T.; Curcio, V.; Gardini, L.; Capitanio, M.; Pavone, F. S.

    2018-02-01

    Highly Inclined and Laminated Optical sheet (HILO) microscopy is an optical technique that employs a highly inclined laser beam to illuminate the sample with a thin sheet of light that can be scanned through the sample volume1 . HILO is an efficient illumination technique when applied to fluorescence imaging of thick samples owing to the confined illumination volume that allows high contrast imaging while retaining deep scanning capability in a wide-field configuration. The restricted illumination volume is crucial to limit background fluorescence originating from portions of the sample far from the focal plane, especially in applications such as single molecule localization and super-resolution imaging2-4. Despite its widespread use, current literature lacks comprehensive reports of the actual advantages of HILO in these kinds of microscopies. Here, we thoroughly characterize the propagation of a highly inclined beam through fluorescently labeled samples and implement appropriate beam shaping for optimal application to single molecule and super-resolution imaging. We demonstrate that, by reducing the beam size along the refracted axis only, the excitation volume is consequently reduced while maintaining a field of view suitable for single cell imaging. We quantify the enhancement in signal-tobackground ratio with respect to the standard HILO technique and apply our illumination method to dSTORM superresolution imaging of the actin and vimentin cytoskeleton. We define the conditions to achieve localization precisions comparable to state-of-the-art reports, obtain a significant improvement in the image contrast, and enhanced plane selectivity within the sample volume due to the further confinement of the inclined beam.

  18. Inclined fluidized bed system for drying fine coal

    Science.gov (United States)

    Cha, Chang Y.; Merriam, Norman W.; Boysen, John E.

    1992-02-11

    Coal is processed in an inclined fluidized bed dryer operated in a plug-flow manner with zonal temperature and composition control, and an inert fluidizing gas, such as carbon dioxide or combustion gas. Recycled carbon dioxide, which is used for drying, pyrolysis, quenching, and cooling, is produced by partial decarboxylation of the coal. The coal is heated sufficiently to mobilize coal tar by further pyrolysis, which seals micropores upon quenching. Further cooling with carbon dioxide enhances stabilization.

  19. Direct restoration of endodontically treated maxillary central incisors: post or no post at all?

    Science.gov (United States)

    von Stein-Lausnitz, Manja; Bruhnke, M; Rosentritt, M; Sterzenbach, G; Bitter, K; Frankenberger, R; Naumann, M

    2018-04-30

    The aim of this ex-vivo study was to evaluate the impact of cavity size and glass-fiber post (GFP) placement on the load capability of endodontically treated maxillary incisors directly restored with resin composite. Ninety-six extracted human maxillary central incisors were endodontically treated and distributed to four groups (n = 24): access cavity (A), access cavity and uni-proximal class III cavity (U), access cavity and bi-proximal class III cavity (B), and decoronated tooth (D). Specimens were restored with resin composite, and 12 specimen of each group received an adhesively placed glass-fiber post (P). Prior to linear loading, specimens were exposed to thermo-mechanical loading (TCML). Statistical analysis was performed using log-rank test after TCML, Kruskall-Wallis and Mann-Whitney U test to compare load capabilities (F max) . Significantly more failures occurred in group D for specimens without GFP during TCML (p = 0.001). F max (mean (SD) in N was (A) 513 (124), (AP) 554 (201), (U) 438 (171), (UP) 537 (232) (B) 483 (219), (BP) 536 (281), D 143 (181), and DP 500 (331), and differed significantly among groups (p = 0.003). Pair-wise comparison revealed lower F max values for group D compared to all other groups (p central incisors with cavity sizes up to bi-proximal class III may be successfully directly restored with resin composite. Post placement shows no additional effect except for decoronated endodontically treated incisors. Endodontically treated incisors with access cavities to class III cavities can be successfully restored with resin composite. Post placement for decoronated ETT is recommended.

  20. External apical root resorption in maxillary root-filled incisors after orthodontic treatment: a split-mouth design study.

    Science.gov (United States)

    Llamas-Carreras, José María; Amarilla, Almudena; Espinar-Escalona, Eduardo; Castellanos-Cosano, Lizett; Martín-González, Jenifer; Sánchez-Domínguez, Benito; López-Frías, Francisco Javier

    2012-05-01

    The purpose of this study was to compare, in a split mouth design, the external apical root resorption (EARR) associated with orthodontic treatment in root-filled maxillary incisors and their contralateral teeth with vital pulps. The study sample consisted of 38 patients (14 males and 24 females), who had one root-filled incisor before completion of multiband/bracket orthodontic therapy for at least 1 year. For each patient, digital panoramic radiographs taken before and after orthodontic treatment were used to determine the root resortion and the proportion of external root resorption (PRR), defined as the ratio between the root resorption in the endodontically treated incisor and that in its contralateral incisor with a vital pulp. The student's t-test, chi-square test and logistic regression analysis were used to determine statistical significance. There was no statistically significant difference (p > 0.05) between EARR in vital teeth (1.1 ± 1.0 mm) and endodontically treated incisors (1.1 ± 0.8 mm). Twenty-six patients (68.4%) showed greater resorption of the endodontically treated incisor than its homolog vital tooth (p > 0.05). The mean and standard deviation of PPR were 1.0 ± 0.2. Multivariate logistic regression suggested that PRR does not correlate with any of the variables analyzed. There was no significant difference in the amount or severity of external root resorption during orthodontic movement between root-filled incisors and their contralateral teeth with vital pulps.

  1. Test of the Angle Detecting Inclined Sensor (ADIS) Technique for Measuring Space Radiation

    Science.gov (United States)

    Connell, J. J.; Lopate, C.; McLaughlin, K. R.

    2009-12-01

    In February 2008 we exposed an Angle Detecting Inclined Sensor (ADIS) prototype to beams of 150 MeV/u 78Kr and fragments at the National Superconducting Cyclotron Laboratory's (NSCL) Coupled Cyclotron Facility (CCF). ADIS is a highly innovative and uniquely simple detector configuration used to determine the angles of incidence of heavy ions in energetic charged particle instruments. Corrections for angle of incidence are required for good charge and mass separation. An ADIS instrument is under development to fly on the GOES-R series of weather satellites. The prototype tested consisted of three ADIS detectors, two of which were inclined at an angle to the telescope axis, forming the initial detectors in a five-detector telescope stack. By comparing the signals from the ADIS detectors, the angle of incidence may be determined and a pathlength correction applied to charge and mass determinations. Thus, ADIS replaces complex position sensing detectors with a system of simple, reliable and robust Si detectors. Accelerator data were taken at multiple angles to both primary and secondary beams with a spread of energies. This test instrument represents an improvement over the previous ADIS prototype in that it used oval inclined detectors and a much lower-mass support structure, thus reducing the number of events passing through dead material. These data show a charge peak resolution of 0.18 ± 0.01 e at Br (Z = 35), excellent for such a simple instrument. We will present the results of this test. The ADIS instrument development project was partially funded by NASA under the Living With a Star (LWS) Targeted Research and Technology program (grant NAG5-12493).

  2. A Numerical Simulation of Transport Phenomena During the Horizontal Single Belt Casting Process Using an Inclined Feeding System

    Science.gov (United States)

    Xu, Mianguang; Isac, Mihaiela; Guthrie, Roderick I. L.

    2018-06-01

    Horizontal single belt casting (HSBC) has great potential to replace current conventional continuous casting (CCC) processes for sheet metal production, by directly casting 3 to 1 mm sheet for the automobile industry. In the present paper, two-dimensional mathematical models were developed to study transport phenomena, for the case of an inclined wall feeding system for a liquid aluminum wrought alloy (AA6111). Based on the commercial software ANSYS FLUENT 14.5 and user-defined functions, a two-layer turbulence model was used to examine the fluid flow emanating from a slot nozzle set above a water-cooled, high-speed, steel belt. The Volume of Fluid (VOF) method was used to predict the shape of the melt-air interface. A transformed coordinate system ( x', y') was established in order to analyze the fluid flow on the inclined wall of the feeding system. The total pressure gauge gradient ( ∂p total/ ∂x) was used to describe the behavior of the melt film inside the slot nozzle of the head box. The modeling results show that during the melt film falling process, the total gauge pressure varies within the slot nozzle, which can decrease the stability of the falling film. The first impingement between the falling film and the inclined refractory wall of the feeding system gives rise to a local oscillation, and this influences the stability of the melt film moving downwards. At the rear meniscus position between the inclined wall and the moving belt, there is a clear vibration of the air-melt interface, together with a recirculation zone. The weak vibration of the air-melt interface could be induced by the periodic variation of the melt-air interface. Moreover, the formation of tiny air pockets is predicted. Finally, on the inclined wall of the feeding system, a suitable length of the transition area is needed to avoid over-acceleration of the melt film due to the force of gravity.

  3. A Numerical Simulation of Transport Phenomena During the Horizontal Single Belt Casting Process Using an Inclined Feeding System

    Science.gov (United States)

    Xu, Mianguang; Isac, Mihaiela; Guthrie, Roderick I. L.

    2018-03-01

    Horizontal single belt casting (HSBC) has great potential to replace current conventional continuous casting (CCC) processes for sheet metal production, by directly casting 3 to 1 mm sheet for the automobile industry. In the present paper, two-dimensional mathematical models were developed to study transport phenomena, for the case of an inclined wall feeding system for a liquid aluminum wrought alloy (AA6111). Based on the commercial software ANSYS FLUENT 14.5 and user-defined functions, a two-layer turbulence model was used to examine the fluid flow emanating from a slot nozzle set above a water-cooled, high-speed, steel belt. The Volume of Fluid (VOF) method was used to predict the shape of the melt-air interface. A transformed coordinate system (x', y') was established in order to analyze the fluid flow on the inclined wall of the feeding system. The total pressure gauge gradient (∂p total/∂x) was used to describe the behavior of the melt film inside the slot nozzle of the head box. The modeling results show that during the melt film falling process, the total gauge pressure varies within the slot nozzle, which can decrease the stability of the falling film. The first impingement between the falling film and the inclined refractory wall of the feeding system gives rise to a local oscillation, and this influences the stability of the melt film moving downwards. At the rear meniscus position between the inclined wall and the moving belt, there is a clear vibration of the air-melt interface, together with a recirculation zone. The weak vibration of the air-melt interface could be induced by the periodic variation of the melt-air interface. Moreover, the formation of tiny air pockets is predicted. Finally, on the inclined wall of the feeding system, a suitable length of the transition area is needed to avoid over-acceleration of the melt film due to the force of gravity.

  4. The Use of Cone Beam Computed Tomography (CBCT to Determine Supernumerary and Impacted Teeth Position in Pediatric Patients: A Case Report

    Directory of Open Access Journals (Sweden)

    Hossein Nematolahi

    2013-03-01

    Full Text Available A case of a compound odontoma which caused delayed eruption of right maxillary central incisor in a ten year old girl is presented with clinical and radiographic findings. The patient presented with complaint of a hard painless swelling in the right anterior region of the maxilla and absence of right maxillary central incisor. After clinical examination, periapical and occlusal radiographs of the mentioned region were taken. Impacted maxillary right central incisor was seen malformed shape on the intraoral radiographs. After taking a cone beam computed tomography (CBCT a compound odontoma associated with the labial aspect of impacted maxillary right central incisor was diagnosed and then removed by simple local excision under local anesthesia. The removal of the odontoma was followed by forced eruption of the impacted central incisor. After three months the tooth returned to its original position.

  5. A Rare Bilateral Presentation of Multiple Dens Invaginatus, Shovel-Shaped Incisor and Talon Cusp With Mesiodens.

    Science.gov (United States)

    Hegde, S; Jain, M; Shubha, A B

    2014-01-01

    The aim of this paper is to describe a unique and unusual case of concomitant appearance of morphological dental anomalies in the maxillary anterior region, along with its management in a patient with no systemic abnormality. This case report describes the clinical and radiographic features of talon cusp, dens invaginatus, shovel-shaped incisors and a supernumerary tooth occurring in a single patient, which is a rare presentation. All 4 permanent maxillary incisors had dens invaginatus, the permanent maxillary canines showed the presence of talon cusps, the permanent maxillary central incisors were shovel-shaped and an erupted mesiodens was also observed. Treatment included restorative, surgical and orthodontic approaches.

  6. Orthodontic treatment of the patients having germinated tooth in the incisor region of maxilla : 2 cases report

    OpenAIRE

    佐藤, 和朗; 小田島, 晶子; 三條, 晃; 桑島, 幸紀; 山田, 裕之; 三浦, 廣行; サトウ, カズロウ; オダシマ, アキコ; サンジョウ, アキラ; クワジマ, ユキノリ; ヤマダ, ヒロユキ; ミウラ, ヒロユキ; Kazuro, SATOH; Akiko, ODASHIMA; Akira, SANJO

    2010-01-01

    We treated the malocclusion of two boys having a germinated tooth in the incisor region of maxilla. In case 1, the germinated tooth was located at the right lateral incisor, in case 2, at the left central incisor region of maxilla. The X-ray and CT examinations revealed that the germinated tooth was united by enamel and dentin and the dental pulp cavity was joined in both cases. So we carried out treatments to avoid pulpectomy in both cases; the germinated tooth aligned in the upper dental ar...

  7. Relation between agenesis and shape anomaly of maxillary lateral incisors and canine impaction

    Directory of Open Access Journals (Sweden)

    Anísio Bueno de Carvalho

    2012-12-01

    Full Text Available OBJECTIVE: The purpose was to obtain information about the relation between agenesis and shape anomaly of maxillary lateral incisors and canine impaction. METHODS: Seventy-three patients with canine impaction and 73 control patients, without canine impaction, were evaluated. The mesiodistal distances of the maxillary lateral incisors adjacent to the impacted canines and the correspondent mandibular lateral incisors were measured. The adjacent lateral incisors were classified in: 1 - absent, 2 - small, 3 - peg-shaped, 4 - standard. RESULTS: The results showed that among the patients with impacted canines, there were 21 anomalous teeth (small and peg-shaped and among the control patients there were only three small and peg-shaped teeth, with a statistically significant difference (p = 0.001. No patients were found with impacted canines and absent lateral incisors. CONCLUSION: It was concluded that in patients with anomalous lateral incisors (small and peg-shaped there is a probability to present impacted canines and this must be considered.OBJETIVO: o objetivo foi obter informação sobre a relação existente entre a agenesia e/ou anomalia de forma de incisivos laterais superiores e impacção de caninos. MÉTODOS: foram avaliados 73 pacientes com impacção de caninos e 73 pacientes controle, sem impacção de caninos. Foram medidas as distâncias mesiodistais dos incisivos laterais superiores adjacentes aos caninos impactados e os incisivos laterais correspondentes inferiores. Os incisivos laterais adjacentes foram classificados em: 1 - ausentes; 2 - pequenos; 3 - conoides; 4 - normais. RESULTADOS: os resultados mostraram que no grupo de pacientes com caninos impactados foram encontrados 22 dentes anômalos (pequenos e conoides, e no grupo controle apenas três dentes pequenos e conoides, sendo uma diferença estatisticamente significativa (p=0,001. Não foram encontrados pacientes com canino impactado e incisivo lateral ausente. CONCLUS

  8. Self-other resonance, its control and prosocial inclinations: Brain-behavior relationships.

    Science.gov (United States)

    Christov-Moore, Leonardo; Iacoboni, Marco

    2016-04-01

    Humans seem to place a positive reward value on prosocial behavior. Evidence suggests that this prosocial inclination is driven by our reflexive tendency to share in the observed sensations, emotions and behavior of others, or "self-other resonance". In this study, we examine how neural correlates of self-other resonance relate to prosocial decision-making. Subjects performed two tasks while undergoing fMRI: observation of a human hand pierced by a needle, and observation and imitation of emotional facial expressions. Outside the scanner, subjects played the Dictator Game with players of low or high income (represented by neutral-expression headshots). Subjects' offers in the Dictator Game were correlated with activity in neural systems associated with self-other resonance and anticorrelated with activity in systems implicated in the control of pain, affect, and imitation. Functional connectivity between areas involved in self-other resonance and top-down control was negatively correlated with subjects' offers. This study suggests that the interaction between self-other resonance and top-down control processes are an important component of prosocial inclinations towards others, even when biological stimuli associated with self-other resonance are limited. These findings support a view of prosocial decision-making grounded in embodied cognition. © 2016 Wiley Periodicals, Inc.

  9. Shallow magnetic inclinations in the Cretaceous Valle Group, Baja California: remagnetization, compaction, or terrane translation?

    Science.gov (United States)

    Smith, Douglas P.; Busby, Cathy J.

    1993-10-01

    Paleomagnetic data from Albian to Turonian sedimentary rocks on Cedros Island, Mexico (28.2° N, 115.2° W) support the interpretation that Cretaceous rocks of western Baja California have moved farther northward than the 3° of latitude assignable to Neogene oblique rifting in the Gulf of California. Averaged Cretaceous paleomagnetic results from Cedros Island support 20 ± 10° of northward displacement and 14 ± 7° of clockwise rotation with respect to cratonic North America. Positive field stability tests from the Vizcaino terrane substantiate a mid-Cretaceous age for the high-temperature characteristic remanent magnetization in mid-Cretaceous strata. Therefore coincidence of characteristic magnetization directions and the expected Quaternary axial dipole direction is not due to post mid-Cretaceous remagnetization. A slump test performed on internally coherent, intrabasinal slump blocks within a paleontologically dated olistostrome demonstrates a mid-Cretaceous age of magnetization in the Valle Group. The in situ high-temperature natural remanent magnetization directions markedly diverge from the expected Quaternary axial dipole, indicating that the characteristic, high-temperature magnetization was acquired prior to intrabasinal slumping. Early acquisition of the characteristic magnetization is also supported by a regional attitude test involving three localities in coherent mid-Cretaceous Valle Group strata. Paleomagnetic inclinations in mudstone are not different from those in sandstone, indicating that burial compaction did not bias the results toward shallow inclinations in the Vizcaino terrane.

  10. Effect of cup inclination on predicted contact stress-induced volumetric wear in total hip replacement.

    Science.gov (United States)

    Rijavec, B; Košak, R; Daniel, M; Kralj-Iglič, V; Dolinar, D

    2015-01-01

    In order to increase the lifetime of the total hip endoprosthesis, it is necessary to understand mechanisms leading to its failure. In this work, we address volumetric wear of the artificial cup, in particular the effect of its inclination with respect to the vertical. Volumetric wear was calculated by using mathematical models for resultant hip force, contact stress and penetration of the prosthesis head into the cup. Relevance of the dependence of volumetric wear on inclination of the cup (its abduction angle ϑA) was assessed by the results of 95 hips with implanted endoprosthesis. Geometrical parameters obtained from standard antero-posterior radiographs were taken as input data. Volumetric wear decreases with increasing cup abduction angle ϑA. The correlation within the population of 95 hips was statistically significant (P = 0.006). Large cup abduction angle minimises predicted volumetric wear but may increase the risk for dislocation of the artificial head from the cup in the one-legged stance. Cup abduction angle and direction of the resultant hip force may compensate each other to achieve optimal position of the cup with respect to wear and dislocation in the one-legged stance for a particular patient.

  11. Collisionless encounters and the origin of the lunar inclination.

    Science.gov (United States)

    Pahlevan, Kaveh; Morbidelli, Alessandro

    2015-11-26

    The Moon is generally thought to have formed from the debris ejected by the impact of a planet-sized object with the proto-Earth towards the end of planetary accretion. Models of the impact process predict that the lunar material was disaggregated into a circumplanetary disk and that lunar accretion subsequently placed the Moon in a near-equatorial orbit. Forward integration of the lunar orbit from this initial state predicts a modern inclination at least an order of magnitude smaller than the lunar value--a long-standing discrepancy known as the lunar inclination problem. Here we show that the modern lunar orbit provides a sensitive record of gravitational interactions with Earth-crossing planetesimals that were not yet accreted at the time of the Moon-forming event. The currently observed lunar orbit can naturally be reproduced via interaction with a small quantity of mass (corresponding to 0.0075-0.015 Earth masses eventually accreted to the Earth) carried by a few bodies, consistent with the constraints and models of late accretion. Although the encounter process has a stochastic element, the observed value of the lunar inclination is among the most likely outcomes for a wide range of parameters. The excitation of the lunar orbit is most readily reproduced via collisionless encounters of planetesimals with the Earth-Moon system with strong dissipation of tidal energy on the early Earth. This mechanism obviates the need for previously proposed (but idealized) excitation mechanisms, places the Moon-forming event in the context of the formation of Earth, and constrains the pristineness of the dynamical state of the Earth-Moon system.

  12. Flame spread over inclined electrical wires with AC electric fields

    KAUST Repository

    Lim, Seung J.

    2017-07-21

    Flame spread over polyethylene-insulated electrical wires was studied experimentally with applied alternating current (AC) by varying the inclination angle (θ), applied voltage (VAC), and frequency (fAC). For the baseline case with no electric field applied, the flame spread rate and the flame width of downwardly spreading flames (DSFs) decreased from the horizontal case for −20° ≤ θ < 0° and maintained near constant values for −90° ≤ θ < −20°, while the flame spread rate increased appreciably as the inclination angle of upwardly spreading flames (USFs) increased. When an AC electric field was applied, the behavior of flame spread rate in DSFs (USFs) could be classified into two (three) sub-regimes characterized by various functional dependences on VAC, fAC, and θ. In nearly all cases of DSFs, a globular molten polyethylene formed ahead of the spreading flame edge, occasionally dripping onto the ground. In these cases, an effective flame spread rate was defined to represent the burning rate by measuring the mass loss due to dripping. This effective spread rate was independent of AC frequency, while it decreased linearly with voltage and was independent of the inclination angle. In DSFs, when excessively high voltage and frequency were applied, the dripping led to flame extinction during propagation and the extinction frequency correlated well with applied voltage. In USFs, when high voltage and frequency were applied, multiple globular molten PEs formed at several locations, leading to ejections of multiple small flame segments from the main flame, thereby reducing the flame spread rate, which could be attributed to the electrospray phenomenon.

  13. Sensitivity determination of CR-39 from Normal and inclined incidence

    International Nuclear Information System (INIS)

    Abou, A.A.; El-Kheir, A.A.; Daas, A.F.; Awwad, Z.; Reda, A.M.

    2000-01-01

    An experimental study have been carried out on alpha- particle track opening (Major and minor axes) using alpha-particles of different energies incident with different angels in addition to the normal incidence. The sensitivity of CR-39 in present work is determined for each of normal and inclined incidence. The results indicated a difference in the sensitivity according to angle of incidence. The variation of alpha- particle tracks (major and minor axes) are calculated and compared with our measured values. Also, it is found that the sensitivity of CR-39 detector is change due to the storage time at room temperature

  14. Inclined indentation of smooth wedge in rock mass

    Science.gov (United States)

    Chanyshev, AI; Podyminogin, GM; Lukyashko, OA

    2018-03-01

    The article focuses on the inclined rigid wedge indentation into a rigid-plastic half-plane of rocks with the Mohr–Coulomb-Mohr plasticity. The limiting loads on different sides of the wedge are determined versus the internal friction angle, cohesion and wedge angle. It is shown that when the force is applied along the symmetry axis of the wedge, the zone of plasticity is formed only on one wedge side. In order to form the plasticity zone on both sides of the wedge, it is necessary to apply the force asymmetrically relative to the wedge symmetry axis. An engineering solution for the asymmetrical case implementation is suggested.

  15. Inclinations of Egyptian pyramids and finding of the divine essence

    OpenAIRE

    GRIGORIEV STANISLAV ARKADIEVICH

    2015-01-01

    The aim of this research is discovery of astronomical reasons in orientation of slopes of Egyptian pyramids used as tombs for pharaohs of Ancient Egypt. The article contains results of statistical analysis of change in inclination of slopes of the pyramids (3rd 2nd millennia BC) depending on time of their building. The first year of the corresponding pharaoh’s reign has been accepted, as usually it is considered that building of pyramids ones started during either the first or second year of ...

  16. Mollenhauer Aligning Auxiliary for Bodily Alignment of Blocked-out Lateral Incisors in Preadjusted Edgewise Appliance Therapy

    Directory of Open Access Journals (Sweden)

    Sreekrishnan B Nair

    2014-01-01

    Conclusion: Mollenhauer aligning auxiliary can be effectively used for the bodily alignment of lingually placed lateral incisors in preadjusted edgewise appliance therapy as an alternative to torquing with rectangular wires.

  17. Lengths of the maxillary central incisor, the nasal bone, and the anterior cranial base in different skeletal malocclusions

    DEFF Research Database (Denmark)

    Arntsen, Torill; Kjær, Inger; Sonnesen, Liselotte

    2009-01-01

    with neutral occlusion and normal craniofacial morphology (n=39). Two-way ANOVA tests were used to evaluate differences in lengths between groups and gender. Results. Statistically shorter maxillary central incisor length was found in the open bite group (p

  18. Resorption of lateral incisors during canine eruption: two clinical cases with focus on root length and heredity

    DEFF Research Database (Denmark)

    Zargham, Mostafa; Kjær, Inger

    2016-01-01

    Introduction: It is well-known that pressure from orthodontic appliance can provoke root resorption in dentitions with short roots. The purpose of this case report is to demonstrate two clinical cases with focus on root length in dentitions exposed due to pressure from erupting teeth...... resorption on her lateral incisor roots, extremely short roots in the central incisors, and short roots. The intraoral photos demonstrated light crowding in the maxilla. The orthopantomogram of the girl’s mother demonstrated extremely short roots in general. Conclusion: This pilot study indicates that short...... root length in general and abnormal incisor morphology are phenotypic traits that were characteristic for both girls who presented with severe lateral incisor resorption due to erupting canines. Furthermore, short roots were also demonstrated in the mothers. Accordingly, short root length in general...

  19. Revascularization of an impacted, immature dilacerated permanent maxillary central incisor associated with odontoma and a supernumerary tooth

    Directory of Open Access Journals (Sweden)

    Priya Subramaniam

    2013-01-01

    Full Text Available To intentionally replant an impacted immature permanent maxillary central incisor in the mixed dentition period followed by revascularization in order to achieve apical root closure. A 9-year-old boy presented with retained maxillary left primary incisors. Radiographic evaluation revealed the presence of a supernumerary tooth and an odontoma associated with an impacted permanent maxillary left central incisor, having root dilaceration. Treatment included surgical removal of mesiodens and odontoma. The impacted dilacerated permanent central incisor was removed and intentionally replanted, followed by revascularization of pulp. During the follow-up, root end closure with narrowing of canal space was observed, patient has been asymptomatic and the tooth remains vital. Revascularization of the immature reimplanted tooth showed continued root development and thickening of the lateral dentinal walls through deposition of new hard tissue and narrowing of the canal space.

  20. Duration for Apical Barrier Formation in Necrotic Immature Permanent Incisors Treated With Calcium Hydroxide Apexification Using Ultrasonic or Hand Filing

    Directory of Open Access Journals (Sweden)

    Li-Wan Lee

    2010-08-01

    Conclusion: Ultrasonic filing with 0.2% chlorhexidine as an irrigant is effective for disinfection of the root canal and can shorten the duration for apical barrier formation in necrotic permanent incisors treated with calcium hydroxide apexification.

  1. The prevalence of Molar Incisor Hypomineralisation (MIH) in a group of Italian school children.

    Science.gov (United States)

    Calderara, P C; Gerthoux, P M; Mocarelli, P; Lukinmaa, P L; Tramacere, P L; Alaluusua, S

    2005-06-01

    This epidemiological study in a group of Italian children was undertaken in order to increase our knowledge of the prevalence of Molar Incisor Hypomineralisation (MIH) in different European countries. A population of school children aged 7.3 - 8.3 years, living in Lissone, Northern Italy, was examined for the presence and severity of MIH. Of a total of 227 children (113 females), 31 (13.7%) had MIH, the tooth prevalence in the permanent first molars being 5.8%. Fifteen children (6.6%) had demarcated opacities in the incisors with a tooth prevalence of 2.1%. The defects in the molars were mild with the exception of one child who had severe defects. MIH was quite common in this Italian town, and the prevalence figures were near those reported in Scandinavian countries but clearly higher than those from Dresden, Germany.

  2. Prevalence of molar incisor hypomineralization in school children aged 8-12 years in Chennai

    Directory of Open Access Journals (Sweden)

    Savitha Deepthi Yannam

    2016-01-01

    Full Text Available Objective: To investigate the prevalence and severity of molar incisor hypomineralization (MIH. Materials and Methods: A sample of 2,864 students aged 8-12 years were selected from government and private schools in Chennai. MIH was diagnosed clinically based on the diagnostic criteria established by the European Academy of Pediatric Dentistry (EAPD 2003. Results: A total of 277 children (9.7% had MIH. There was statistically significant difference in prevalence related to age but there was no statistical difference in prevalence with respect to gender. Conclusion: Prevalence of MIH was 9.7% in the child population residing in Chennai. Males and females were equally affected. The rate of occurrence and severity of MIH are more in the right mandibular first molar. The severity of MIH is more in molars compared to incisors (P < 0.001 and is more in government schools compared to private schools (P = 0.002.

  3. [A computer aided design approach of all-ceramics abutment for maxilla central incisor].

    Science.gov (United States)

    Sun, Yu-chun; Zhao, Yi-jiao; Wang, Yong; Han, Jing-yun; Lin, Ye; Lü, Pei-jun

    2010-10-01

    To establish the computer aided design (CAD) software platform of individualized abutment for the maxilla central incisor. Three-dimentional data of the incisor was collected by scanning and geometric transformation. Data mainly included the occlusal part of the healing abutment, the location carinae of the bedpiece, the occlusal 1/3 part of the artificial gingiva's inner surface, and so on. The all-ceramic crown designed in advanced was "virtual cutback" to get the original data of the abutment's supragingival part. The abutment's in-gum part was designed to simulate the individual natural tooth root. The functions such as "data offset", "bi-rail sweep surface" and "loft surface" were used in the process of CAD. The CAD route of the individualized all-ceramic abutment was set up. The functions and application methods were decided and the complete CAD process was realized. The software platform was basically set up according to the requests of the dental clinic.

  4. [A case of restoration using IPS empress (staining technique) for upper central incisors].

    Science.gov (United States)

    Hata, Utako

    2007-07-01

    The patient had esthetically unacceptable upper left central incisor crowns. The case was restored using Empress (staining technique) for the upper central incisors on both sides. In making all-ceramic crowns, it is necessary to reproduce the shape and color near to those of the natural tooth. We should not overlook the importance of diagnostic waxing-up, provisional restoration, tooth preparation, gingival retraction and others, to achieve excellent appearance, function and biocompatibility. It is effective to use the staining technique for an anterior tooth crown in order to obtain esthetically satisfactory results by the papilla being present in such cases as the distance from the base of the contact point to the crest of the bone is 5 mm or less.

  5. Molar incisor hypomineralization: Considerations about treatment in a controlled longitudinal case

    Directory of Open Access Journals (Sweden)

    Daniela Cristina de Oliveira

    2015-01-01

    Full Text Available Molar incisor hypomineralization (MIH is a defect in the tooth enamel of systemic origin and may affect one or all four first permanent molars frequently associated with the permanent incisors. This case reports a 7-year-old child with severe MIH in the permanent molars associated with tooth decay and intense pain. In the first stage of treatment, therapy was performed with fluoride varnish and restoration with glass ionomer cement (GIC. After 6 years of clinical and radiographic follow-up, the restorations presented wear and fractures on the margins, indicating their replacement with composite resin. Severe cases of MIH in the early permanent molars can be treated with varnish and GIC to restore the patient′s comfort and strengthen the hypomineralized dental structures. The clinical and radiographic monitoring frequently indicated when the restoration with composite resin should be performed.

  6. Organic and inorganic content of fluorotic rat incisors measured by FTIR spectroscopy

    Science.gov (United States)

    Porto, Isabel Maria; Saiani, Regina Aparecida; Chan, K. L. Andrew; Kazarian, Sergei G.; Gerlach, Raquel Fernanda; Bachmann, Luciano

    2010-09-01

    Details on how fluoride interferes in enamel mineralization are still controversial. Therefore, this study aimed at analyzing the organic contents of fluorosis-affected teeth using Fourier Transformation Infrared spectroscopy. To this end, 10 male Wistar rats were divided into two groups: one received 45 ppm fluoride in distilled water for 60 days; the other received distilled water only. Then, the lower incisors were removed and prepared for analysis by two FTIR techniques namely, transmission and micro-ATR. For the first technique, the enamel was powdered, whereas in the second case one fluorotic incisor was cut longitudinally for micro-ATR. Using transmission and powdered samples, FTIR showed a higher C-H content in the fluorotic enamel compared with control enamel ( p amelogenesis. Further studies along this line may definitely answer some questions regarding protein content in fluorotic enamel as well as their origin.

  7. Complications of untreated molar-incisor hypomineralization in a 12-year-old boy

    Directory of Open Access Journals (Sweden)

    Shubha Arehalli Bhaskar

    2012-11-01

    Full Text Available Complications arising because of untreated molar-incisor hypomineralization (MIH have received little mention in the dental literature. However, this can be an area of concern, with severe consequences in rare cases. Hence, early recognition and prompt management of MIH is essential for long-term oral health of affected individuals. This paper describes an untreated case of severe MIH that resulted in infection of facial spaces.

  8. Canine and incisor microwear in pitheciids and Ateles reflects documented patterns of tooth use.

    Science.gov (United States)

    Delezene, Lucas K; Teaford, Mark F; Ungar, Peter S

    2016-09-01

    Platyrrhine species differ in the extent to and the manner in which they use their incisors and canines during food ingestion. For example, Ateles uses its anterior teeth to process mechanically nondemanding soft fruits, while the sclerocarp-harvesting pitheciids rely extensively on these teeth to acquire and process more demanding foods. Pitheciids themselves vary in anterior tooth use, with the pitheciines (Cacajao, Chiropotes, and Pithecia) noted to use their robust canines in a variety of ways to predate seeds, while Callicebus, which rarely predates seeds, uses its incisors and exceptionally short canines to scrape tough mesocarp from fruits. To investigate the relationship between tooth use and dental wear, microwear textures were investigated for the anterior teeth of these five genera of platyrrhine primates. Using a white light confocal microscope, 12 microwear texture attributes that reflect feature size, anisotropy, density, and complexity were recorded from high-resolution epoxy casts of the incisors and canines of adult wild-collected Brazilian specimens of Ateles, Callicebus, Cacajao, Chiropotes, and Pithecia. Pitheciine canines tend to have deep microwear features and complex, anisotropic microwear textures, while Ateles anterior teeth tend to have very small features, low feature density, and less complex and anisotropic surfaces. Callicebus incisor and canine microwear is generally intermediate in size and complexity between those extremes. These findings align with expectations from reported field observations of tooth use and illustrate the potential for using microwear texture analysis to infer patterns of anterior tooth use in extinct primates. Am J Phys Anthropol 161:6-25, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  9. Treatment of ankylosed maxillary central incisors by segmental osteotomy with autogenous bone graft.

    Science.gov (United States)

    You, Kug-Ho; Min, Yon-Sook; Baik, Hyoung-Seon

    2012-04-01

    This case report describes the treatment of a 16-year-old girl with ankylosed maxillary central incisors that were noticeably infraoccluded and labially displaced. We performed a segmental osteotomy with an autogenous bone graft in a single-stage surgery to align and level the ankylosed teeth. The dento-osseous segment was successfully repositioned with satisfactory periodontal results. Copyright © 2012 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  10. Periodontal and gingival incisor findings in patients with anterior open bite in the mixed dentition.

    Science.gov (United States)

    Bechtold, Till Edward; Briegleb, Henning K

    2010-05-01

    The objective of this study was to investigate any association between anterior open bite and periodontal health of the front teeth during mixed dentition. We investigated the periodontal and gingival status of the teeth with dysfunctional and/or subfunctional loading in the open-bite area in 9- to 12-year-old children. We examined 36 subjects with anterior open bite between the ages of 9 and 12 years who had presented for the first time at the Department of Orthodontics, University of Tübingen. A control group of 36 children of the same age with a physiologic incisor relationship--vertical overbite and sagittal overjet were between 1 and 3 mm--were compared. In addition to overjet, the Silness-Löe plaque index, the modified Löe-Silness gingival index, pocket depth and attachment loss were measured and documented at each of the four surfaces (mesial, distal, oral and vestibular) of the upper and lower incisors. The subjects with anterior open bite exhibited significantly more plaque in the malocclusion area than children with a physiologic incisor relationship; the differences were statistically highly significant. The subjects with anterior open bite demonstrated slightly higher degrees of inflammation and a slight increase in periodontal pocket depths than the control group. Periodontal attachment loss was diagnosed in very few areas in both study groups, while attachment loss was slightly more frequent in those with anterior open bite. We observed a higher risk for caries in the malocclusion area in the late mixed dentition phase, as the subjects with anterior open bite presented significantly more plaque accumulation in the incisor area. However, no pathological periodontal anomalies have been detected so far.

  11. Surgical and Orthodontic Management of Fused Maxillary Central and Lateral Incisors in Early Mixed Dentition Stage

    OpenAIRE

    Ramamurthy, Suresh; Satish, Ramaswamy; Priya, Kalidass

    2014-01-01

    Fusion is one of the developmental dental anomalies in which two adjacent teeth are joined at the crown level forming a single tooth with an enlarged crown. Fusion causes some clinical problems such as unaesthetic appearance, pain, caries, and malocclusion. The management of fusion often needs multidisciplinary approach to give best possible esthetic and functional outcome. This paper reports a case of 9-year-old boy with fused maxillary left central and lateral incisors who was treated with ...

  12. The genetics of shovel shape in maxillary central incisors in man.

    Science.gov (United States)

    Blanco, R; Chakraborty, R

    1976-03-01

    From dental casts of 94 parent-offspring and 127 full-sib pairs, sampled from two Chilean populations, shovelling indices are computed to measure the degree of shovelling of maxillary central incisors quantitatively. Genetic correlations are computed to determine the role of genetic factors in explaining the variation in this trait. Assuming only hereditary factors to be responsible for the transmission of shovel shape, 68% of total variability is ascribed to the additive effect of genes.

  13. Treatment of Class II subdivision malocclusion with congenitally missing upper lateral incisors: A case report

    OpenAIRE

    Siddharth Mehta; Ashima Valiathan; Arun Urala

    2014-01-01

    Orthodontic treatment for patients with unilateral or bilateral congenitally missing lateral incisor poses a challenge mainly with regard to treatment planning. The use of a diagnostic setup is one of the most important aids in the decision-making process. Two alternatives, orthodontic space closure or space opening for prosthetic replacement exist. The present case report shows use of the microimplant for unilateral upper molar distalization and space closure in a Class-II division 1 subdivi...

  14. Crowns to create esthetics for mal-aligned central incisors: a case report.

    Science.gov (United States)

    Savadi, Ravindra C; Savadi, Anupama R; Kumar, Preeti Satheesh

    2011-06-01

    This case report describes the smile design of crowded upper central anteriors in a female patient aged 25 years. The patient wanted the correction to be completed in a short period of time. A smile design schedule was drawn up involving root canal treatment of the central incisors and placing posts in both the teeth. All ceramic crowns were then fabricated to establish a very satisfactory and pleasing esthetics.

  15. Crowns to Create Esthetics for Mal-Aligned Central Incisors: A Case Report

    OpenAIRE

    Savadi, Ravindra C.; Savadi, Anupama R.; Kumar, Preeti Satheesh

    2011-01-01

    This case report describes the smile design of crowded upper central anteriors in a female patient aged 25 years. The patient wanted the correction to be completed in a short period of time. A smile design schedule was drawn up involving root canal treatment of the central incisors and placing posts in both the teeth. All ceramic crowns were then fabricated to establish a very satisfactory and pleasing esthetics.

  16. Resorption of Lateral Incisors during Canine Eruption: Two Clinical Cases with Focus on Root Lengths and Heredity

    Directory of Open Access Journals (Sweden)

    Mostafa Zargham

    2016-01-01

    Full Text Available Introduction: It is well-known that pressure from orthodontic appliance can provoke root resorption in dentitions with short roots. The purpose of this case report is to demonstrate two clinical cases with focus on root length in dentitions exposed due to pressure from erupting teeth. This is a pilot study aimed to improve diagnostics for avoiding the resorption of lateral maxillary incisors by pressure from erupting canines. Case Report: The first reported case is of a girl who was 11 years and 7 months old when radiographs showed severe resorption of the lateral incisors, along with malformed central incisors and short roots. The intraoral photos demonstrated light crowding in the maxilla. The orthopantomogram of the girl’s mother demonstrated several short roots. The second reported case is of a girl who was 9 years and 5 months old when radiographs demonstrated nearly complete resorption on her lateral incisor roots, extremely short roots in the central incisors, and short roots. The intraoral photos demonstrated light crowding in the maxilla. The orthopantomogram of the girl’s mother demonstrated extremely short roots in general. Conclusion: This pilot study indicates that short root length in general and abnormal incisor morphology are phenotypic traits that were characteristic for both girls who presented with severe lateral incisor resorption due to erupting canines. Furthermore, short roots were also demonstrated in the mothers. Accordingly, short root length in general could be a phenotypic trait, which should be diagnosed early for preventing severe resorption of lateral incisors during canine eruption.

  17. Evaluation of root canal morphology of human mandibular incisors in Yazd

    Directory of Open Access Journals (Sweden)

    Tabrizi-zadeh M. Assistant Professor

    2003-06-01

    Full Text Available Statement of Problem: The main objective of endodontic therapy is chemomechanical cleansing of entire pulp cavity and its complete obturation with an inert material. During this procedure, the failure of detection and inadequate cleaning of a canal will result in failed endodontic therapy. Therefore, the dentist must have enough knowledge of root canal morphology to treat a tooth successfully."nAim: The aim of this study was to determine the number and type of root canals of mandibular incisor teeth."nMaterials and Methods: In order to do this in-vitro, descriptive study, 68 non-carious mandibular incisor teethj collected from different clinics in Yazd, were immersed in indian ink, decalcified and cleared."nResults: It was found that 55.9% of the teeth had two separate canals that in 5.5% of them, the canals"nmerged before' apical foramen. In 4.4% of these samples, two separate canals existed along the whole"nroot."nConclusion: Considering high percentage of two canals in lower mandibular incisors, during access preparation, more attempts in detection of the second canal, is emphasized.

  18. Reactive correction of a maxillary incisor in single-tooth crossbite following periodontal therapy.

    Science.gov (United States)

    Huang, Chih-Hao; Brunsvold, Michael A

    2005-05-01

    The reactive correction of a single tooth anterior crossbite following periodontal therapy is described. This case report provides new information regarding correction of a crossbite relationship and con- firms existing reports of tooth movement following periodontal therapy. A 39-year-old woman in good general health presented with a history of recurrent periodontal abscesses of a maxillary incisor. Probing depths of the abscessed tooth ranged from 5 to 12 mm, and class 1 mobility was noted. Radiographs revealed that the tooth had previously been treated endodontically. The patient's periodontal diagnosis was generalized chronic moderate to severe periodontitis. Treatment considerations were complicated by a single-tooth crossbite relationship of the involved incisor and clinical evidence that the periodontal abscess communicated with an apical infection. Treatment of the abscess consisted of cause-related therapy, bone grafting, and occlusal adjustment. Five months after surgical treatment, an edge-to-edge incisal relationship was observed, the first indicator of tooth movement. Further correction to a normal incisal relationship resulted 1 year after modification of the proximal contact. At this time, there was normal probing depth with only slight recession and mobility. Bone fill was radiographically noted. It appears that some cases of maxillary incisor crossbite that are complicated by periodontal disease may be corrected, without orthodontic appliances, following periodontal treatment.

  19. Assessment of age based on the pulp cavity width of the maxillary central incisors

    Directory of Open Access Journals (Sweden)

    Uday Ginjupally

    2014-01-01

    Full Text Available Aims and Objectives: The aim of this study was to estimate the age of the patients belonging to the age group of 15 - 55 years, attending the Department of Oral Medicine and Radiology, St. Joseph Dental College and Hospital, Eluru, based on the radiographic evaluation of the pulp cavity width of the maxillary central incisors. Materials and Methods: The study group comprised of 120 subjects. Intraoral periapical radiographs of the maxillary central incisors were taken for all subjects, using the conventional paralleling angle technique and the pulp cavity width was measured at the cervical and middle third using a digital vernier caliper. The data obtained was subjected to correlation and regression analysis. Results: A negative linear relationship was obtained between the age and pulp cavity width (cervical third, r = -0.459 and middle third, r = -0.704. Cubic regression analysis was done and the regression formulae were obtained. A mean difference of 0.1 years was obtained between the estimated age and real age, indicating the reliability of the derived formula. Conclusion: It can be concluded that the width of the pulp cavity of maxillary central incisors are reliable for estimation of age.

  20. Clinical treatment approach of a child with molar incisor hypomineralization (MIH combined with malocclusion.

    Directory of Open Access Journals (Sweden)

    Rossitza Kabaktchieva

    2012-04-01

    Full Text Available Introduction. Molar incisor hypomineralization (MIH was defined as "hypomineralisation of systemic origin of permanent first molars, frequently associated with affected incisors". MIH includes the presence of demarcated opacity, post eruptive enamel breakdown, atypical restoration. Тhe approach to management suggested: risk identification, early diagnosis, remineralization for prevention of caries and post eruption breakdown, restorations. The clinicians very seldom notice that children with MIH usually have both- hypomineralisation and malocclusions, and they do not discuss combine treatment plan.Aim. To present our interdisciplinary approach to a patient with MIH, combined with malocclusion.Material and methods. We are presenting 9 year old child with contusio and fractura coronae dentis noncomplicata, distal occlusion, overjet, overbite and retrusion. Two consecutive stages were defined: First stage:- Professional oral hygiene and local remineralisation therapy- Vital pulp therapy of tooth 21 - Space gaining for restoration of the lost height of the molars by the means of posterior bite-plane removable appliance- Restoration of the molars with metal inlays- Lingual tipping of the lower incisorsSecond stage:- Class II correction- Growth control Results.First phase: - The tooth 21 was restored with aesthetic composite material;- Occlusion was raised with occlusal restorations (inleys and orthodontic appliance. Second phase:Medialisation of mandible and holding maxillary growth with functional appliance and occipital EOA until class one occlusal relations.Conclusion. Children with MIH should be examined and treated complex in collaboration with orthodontist and if necessary by other specialists too.

  1. Simultaneous Replacement of Maxillary Central Incisors with CEREC Biogeneric Reference Technique: A Case Report

    Directory of Open Access Journals (Sweden)

    Gokhan Akgungor

    2013-06-01

    Full Text Available Biogeneric Reference Technique (BRT of the CEREC 3D v.3.8 software is an effective technique for single anterior ceramic crowns because it provides computer-controlled match of the tooth form to the contralateral tooth. BRT also enables the fabrication of two or more anterior all-ceramic crowns simultaneously. This clinical report demonstrates the clinical application of BRT for designing and milling two central incisors in one appointment using a single optical impression. After completing the virtual design of the first central incisor, it was copied and a mirror image was created. The second central incisor was designed using this replicated image and therefore a computer-controlled symmetry was obtained. The crowns were milled from monolithic feldspathic ceramic blocks and adhesively luted with dual-cured resin cement following dentin conditioning. At the two-year follow-up appointment, the restorations were intact, no adverse effects were noted, and the resultant appearance was highly satisfactory for the patient. A step-by-step protocol is described from design to cementation of these restorations.

  2. Comprehensive therapy of a fusion between a mandibular lateral incisor and supernumerary tooth: case report.

    Science.gov (United States)

    Onçag, Ozant; Candan, Umit; Arikan, Fatih

    2005-08-01

    The term fusion is used to define a developmental anomaly characterised by the union of two adjacent teeth. In the case reported here, clinical and radiographic examinations suggested a unilateral fusion between the mandibular left permanent incisor and a super-numerary tooth. Radiographs showed that the fused teeth had two distinct pulp chambers and canals. A diagnosis of chronic periapical abscess of the supernumerary tooth was made. Before root canal therapy, a periodontal surgical procedure was performed to section the central incisor and its fused supernumerary. Also, odontoplasty was performed on the roots, to establish an anatomy consistent with a normal central incisor. Later, the chronic apical abscess on the supernumerary tooth was instrumented chemo-mechanically, root canal filling was performed and an anterior composite resin restoration was placed. The patient was evaluated for one year after root canal therapy. The tooth was asymptomatic, not exhibiting any pathological root resorption or alveolar resorption, and the anterior composite restoration was intact. Instead of extracting the supernumerary tooth, the application of endodontic, periodontal, and restorative procedures proved to be an alternative treatment.

  3. External apical root resorption in maxillary incisors in orthodontic patients: associated factors and radiographic evaluation.

    Science.gov (United States)

    Nanekrungsan, Kamonporn; Patanaporn, Virush; Janhom, Apirum; Korwanich, Narumanus

    2012-09-01

    This study was performed to evaluate the incidence and degree of external apical root resorption of maxillary incisors after orthodontic treatment and to evaluate particular associated factors related to external apical root resorption. The records and maxillary incisor periapical radiographs of 181 patients were investigated. Crown and root lengths were measured and compared on the pre- and post-treatment periapical radiographs. Crown length was measured from the center of the incisal edge to the midpoint of the cemento-enamel junction (CEJ). Root length was measured from the CEJ midpoint to the root apex. A correction factor for the enlargement difference was used to calculate root resorption. The periapical radiographs of 564 teeth showed that the average root resorption was 1.39±1.27 (8.24±7.22%) and 1.69±1.14 mm (10.16±6.78%) for the maxillary central and lateral incisors, respectively. The results showed that the dilacerated or pointed roots, maxillary premolar extraction cases, and treatment duration were highly significant factors for root resorption (proot resorption (proot resorption among the factors of gender, overbite, tongue-thrusting habit, types of malocclusion, and types of bracket. These results suggested that orthodontic treatment should be carefully performed in pre-treatment extraction patients who have pointed or dilacerated roots and need long treatment duration.

  4. Periostin is an extracellular matrix protein required for eruption of incisors in mice

    International Nuclear Information System (INIS)

    Kii, Isao; Amizuka, Norio; Minqi, Li; Kitajima, Satoshi; Saga, Yumiko; Kudo, Akira

    2006-01-01

    A characteristic tooth of rodents, the incisor continuously grows throughout life by the constant formation of dentin and enamel. Continuous eruption of the incisor is accompanied with formation of shear zone, in which the periodontal ligament is remodeled. Although the shear zone plays a role in the remodeling, its molecular biological aspect is barely understood. Here, we show that periostin is essential for formation of the shear zone. Periostin -/- mice showed an eruption disturbance of incisors. Histological observation revealed that deletion of periostin led to disappearance of the shear zone. Electron microscopy revealed that the disappearance of the shear zone resulted from a failure in digestion of collagen fibers in the periostin -/- mice. Furthermore, immunohistochemical analysis using anti-periostin antibodies demonstrated the restricted localization of periostin protein in the shear zone. Periostin is an extracellular matrix protein, and immunoelectron microscopy showed a close association of periostin with collagen fibrils in vivo. These results suggest that periostin functions in the remodeling of collagen matrix in the shear zone

  5. Orthodontic management of a dilacerated central incisor and partially impacted canine with unilateral extraction - A case report.

    Science.gov (United States)

    Felicita, A Sumathi

    2017-10-01

    To align a dilacerated maxillary central incisor and partially impacted canine with unilateral extraction in a young patient with skeletal deep bite. A 14 year old male patient reported to the hospital with skeletal deep bite (basal plane angle-17°), severe horizontal pattern of growth (Go-Gn to Sn -22°), upright maxillary incisors (U1 to NA -26°) and retroclined lower incisors (L1 to NB -11°). The maxillary left central incisor was dilacerated, and the maxillary left canine was partially impacted. Unilateral extraction of the left maxillary premolar and left mandibular central incisor was done. A canine disimpaction spring was used to align the impacted canine. An anterior bite plane was given to open the bite. Superimposition of lateral cephalogram (T1, T2) revealed bite opening, normal overjet and overbite. There was backward rotation of the mandible and increase in lower anterior facial height. There was no evidence of root resorption or loss of vitality in the dilacerated tooth. Clinically the canine was well aligned in the arch. Orthodontic management of a dilacerated incisor can be done without root resorption or loss of vitality. The partially impacted canine was well aligned in the arch. Unilateral extraction can produce good treatment results.

  6. Predicting daylight illuminance on inclined surfaces using sky luminance data

    Energy Technology Data Exchange (ETDEWEB)

    Li, D.H.W.; Lau, C.C.S.; Lam, J.C. [City University of Hong Kong, Kowloon (China). Dept. of Building and Construction

    2005-07-01

    Daylight illuminance, particularly on vertical surfaces, plays a major role in determining and evaluating the daylighting performance of a building. In many parts of the world, however, the basic daylight illuminance data for various vertical planes are not always readily available. The usual method to obtain diffuse illuminance on tilted planes would be based on inclined surface models using data from the horizontal measurements. Alternatively, the diffuse illuminance on a sloping plane can be computed by integrating the luminance distribution of the sky 'seen' by the plane. This paper presents an approach to estimate the vertical outdoor illuminance from sky luminance data and solar geometry. Sky luminance data recorded from January 1999 to December 2001 in Hong Kong and generated by two well-known sky luminance models (Kittler and Perez) were used to compute the outdoor illuminance for the four principal vertical planes (N, E, S and W). The performance of this approach was evaluated against data measured in the same period. Statistical analysis indicated that using sky luminance distributions to predict outdoor illuminance can give reasonably good agreement with measured data for all vertical surfaces. The findings provide an accurate alternative to determine the amount of daylight on vertical as well as other inclined surfaces when sky luminance data are available. (author)

  7. Geosynchronous inclined orbits for high-latitude communications

    Science.gov (United States)

    Fantino, E.; Flores, R. M.; Di Carlo, M.; Di Salvo, A.; Cabot, E.

    2017-11-01

    We present and discuss a solution to the growing demand for satellite telecommunication coverage in the high-latitude geographical regions (beyond 55°N), where the signal from geostationary satellites is limited or unavailable. We focus on the dynamical issues associated to the design, the coverage, the maintenance and the disposal of a set of orbits selected for the purpose. Specifically, we identify a group of highly inclined, moderately eccentric geosynchronous orbits derived from the Tundra orbit (geosynchronous, eccentric and critically inclined). Continuous coverage can be guaranteed by a constellation of three satellites in equally spaced planes and suitably phased. By means of a high-precision model of the terrestrial gravity field and the relevant environmental perturbations, we study the evolution of these orbits. The effects of the different perturbations on the ground track (which is more important for coverage than the orbital elements themselves) are isolated and analyzed. The physical model and the numerical setup are optimized with respect to computing time and accuracy. We show that, in order to maintain the ground track unchanged, the key parameters are the orbital period and the argument of perigee. Furthermore, corrections to the right ascension of the ascending node are needed in order to preserve the relative orientation of the orbital planes. A station-keeping strategy that minimizes propellant consumption is then devised, and comparisons are made between the cost of a solution based on impulsive maneuvers and one with continuous thrust. Finally, the issue of end-of-life disposal is discussed.

  8. Finite element analysis of inclined nozzle-plate junctions

    International Nuclear Information System (INIS)

    Dixit, K.B.; Seth, V.K.; Krishnan, A.; Ramamurthy, T.S.; Dattaguru, B.; Rao, A.K.

    1979-01-01

    Estimation of stress concentration at nozzle to plate or shell junctions is a significant problem in the stress analysis of nuclear reactors. The topic is a subject matter of extensive investigations and earlier considerable success has been reported on analysis for the cases when the nozzle is perpendicular to the plate or is radial to the shell. Analytical methods for the estimation of stress concentrations for the practical situations when the intersecting nozzle is inclined to the plate or is non-radial to the shell is rather scanty. Specific complications arise in dealing with the junction region when the nozzle with circular cross-section meets the non-circular cut-out on the plate or shell. In this paper a finite element analysis is developed for inclined nozzles and results are presented for nozzle-plate junctions. A method of analysis is developed with a view to achieving simultaneously accuracy of results and simplicity in the choice of elements and their connectivity. The circular nozzle is treated by axisymmetric conical shell elements. The nozzle portion in the region around the junction and the flat plate is dealt with by triangular flat shell elements. Special transition elements are developed for joining the flat shell elements with the axisymmetric elements under non-axisymmetric loading. A substructure method of analysis is adopted which achieves considerable economy in handling the structure and also conveniently combines the different types of elements in the structure. (orig.)

  9. Breakdown of air pockets in downwardly inclined sewerage pressure mains.

    Science.gov (United States)

    Lubbers, C L; Clemens, F H L R

    2006-01-01

    In the Netherlands, wastewater is collected in municipal areas and transported to centralised WWTPs by an extensive system of pressure mains. Over the last decades these pressure mains did not receive much attention in terms of monitoring of performance or maintenance. A recent inventory showed that half of the pressure mains show an increased pressure loss for no directly obvious reason. One of the many causes that account for the reduction of the flow capacity is the occurrence of free gas in the pipeline. During dry weather periods with low flow velocities, gas may accumulate at high points in the system. Once the velocity increases during storm weather flow, the air pockets may be broken down and transported to the end of the system. A research study is started focussing on the description of the gas-water phenomena in wastewater pressure mains with respect to transportation of gas. An experimental facility is constructed for the study of multi-phase flow. This paper describes the preliminary results of experiments on breakdown rates of gas pockets as a function of inclination angle and water flow rate. The results show an increasing breakdown rate with increasing inclination angle.

  10. Co-current descending two-phase flows in inclined packed beds : experiments versus simulations

    Energy Technology Data Exchange (ETDEWEB)

    Atta, A.; Nigam, K.D.P.; Roy, S. [Inst. of Technology, New Delhi (India). Dept. of Chemical Engineering; Schubert, M.; Larachi, F. [Laval Univ., Quebec City, PQ (Canada). Dept. of Chemical Engineering

    2010-10-15

    This paper presented a numerical simulation for an inclined packed bed configuration for two-phase co-current downward flow. A two-phase Eulerian computational fluid dynamics (CFD) model was used to predict the hydrodynamic behaviour. Two different modelling strategies were compared, notably a straight tube with an artificially inclined gravity, and an inclined geometry with straight gravity. The effect of inclination angle of a packed bed on its gas-liquid flow segregation and liquid saturation spatial distribution was measured for varying inclinations and fluid velocities. The CFD model was adapted from a trickle-bed vertical configuration and based on the porous media concept. The predicted pressure drops for the inclined gravity were found to be insensitive to inclination. Therefore, simulations to study the parameters that influence the reduced liquid saturation were performed only with the inclined geometry case. Experimental data obtained using electrical capacitance tomography was used to validate the model predictions. The study showed that a trickle bed CFD model for vertically straight reactors can be effectively implemented in inclined reactor geometries. However, additional research is needed to formulate appropriate drag force closures which should be incorporated in the CFD model for improved quantitative estimation of inclined bed hydrodynamics. 22 refs., 10 figs.

  11. Resorption of maxillary incisors after orthodontic treatment--clinical study of risk factors.

    Science.gov (United States)

    Elhaddaoui, Rajae; Benyahia, Hicham; Azeroual, Mohamed-Faouzi; Zaoui, Fatima; Razine, Rachid; Bahije, Loubna

    2016-03-01

    External apical root resorption (EARR) is one of the major problems associated with orthodontic treatment. Such lesions represent an iatrogenic risk that must be detected as early as possible, with regular radiological follow-up and appropriate therapeutic precautions. The causes and mechanisms leading to susceptibility to root resorption following the application of an orthodontic force are often not clear and are generally said to be of multifactorial origin. The aim of this clinical study was to analyze the factors linked to the occurrence of moderate to severe resorption (MSR) of upper incisors during orthodontic treatment in a group of Moroccan patients treated in the Dento-Facial Orthopedic Department of the Dental Consultation and Treatment Center (Centre de consultation et de traitements dentaires [CCTD]) in Rabat. A total of 82 patients (28% males, 72% females) aged between 12 and 27, with various malocclusions, who had been treated with fixed appliances for at least 1 year and for whom panoramic X-rays at the start, during and at the end of treatment were available, were selected randomly. The reduction in maxillary incisor root length was evaluated using resorption scores. The factors studied in relation to the risk of occurrence of MSR were: age, sex, treatment duration, extraction or non-extraction, type of malocclusion (Class I arch-length discrepancy, Class II, Class III), the vertical diagnosis (normal, supraocclusion, open bite), presence of dysfunction, impacted canines and root morphology. Statistical analysis was performed using SPSS software, version 18.0. Statistical tests used were: Kaplan-Meier analysis and the univariate and multivariate Cox models for the study of factors associated with MSR. The threshold of significance adopted was 0.05. The factors that were significantly associated with the occurrence of MSR at the level of the upper incisors were: tooth type, with a greater risk for the lateral incisor (HR=3.2 95% CI [2.3-4.5] Proot

  12. Improvement in greenhouse solar drying using inclined north wall reflection

    Energy Technology Data Exchange (ETDEWEB)

    Sethi, V.P. [Department of Mechanical Engineering, Punjab Agricultural University, Ludhiana 141004, Punjab (India); Arora, Sadhna [Department of Processing and Food Engineering, Punjab Agricultural University, Ludhiana 141004, Punjab (India)

    2009-09-15

    A conventional greenhouse solar dryer of 6 m{sup 2} x 4 m{sup 2} floor area (east-west orientation) was improved for faster drying using inclined north wall reflection (INWR) under natural as well as forced convection mode. To increase the solar radiation availability onto the product (to be dried) during extreme summer months, a temporary inclined wall covered with aluminized reflector sheet (of 50 {mu}m thickness and reflectance 0.93) was raised inside the greenhouse just in front of the vertical transparent north wall. By doing so, product fully received the reflected beam radiation (which otherwise leaves through the north wall) in addition to the direct total solar radiation available on the horizontal surface during different hours of drying. The increment in total solar radiation input enhanced the drying rate of the product by increasing the inside air and crop temperature of the dryer. Inclination angle of the reflective north wall with vertical ({beta}) was optimized for various selective widths of the tray W (1.5, 2, 2.5 and 3 m) and for different realistic heights of existing vertical north wall (h) at 25 N, 30 N and 35 N latitudes (hot climatic zones). Experimental performance of the improved dryer was tested during the month of May 2008 at Ludhiana (30.56 N) climatic conditions, India by drying bitter gourd (Momordica charantia Linn) slices. Results showed that by using INWR under natural convection mode of drying, greenhouse air and crop temperature increased by 1-6.7 C and 1-4 C, respectively, during different drying hours as compared to, when INWR was not used and saved 13.13% of the total drying time. By using INWR under forced convection mode of drying, greenhouse air and crop temperature increased by 1-4.5 C and 1-3 C, respectively, during different drying hours as compared to, when INWR was not used and saved 16.67% of the total drying time. (author)

  13. Experimental investigation of thermal conductivity coefficient and heat exchange between fluidized bed and inclined exchange surface

    Directory of Open Access Journals (Sweden)

    B. Stojanovic

    2009-06-01

    Full Text Available The paper presents experimental research of thermal conductivity coefficients of the siliceous sand bed fluidized by air and an experimental investigation of the particle size influence on the heat transfer coefficient between fluidized bed and inclined exchange surfaces. The measurements were performed for the specific fluidization velocity and sand particle diameters d p=0.3, 0.5, 0.9 mm. The industrial use of fluidized beds has been increasing rapidly in the past 20 years owing to their useful characteristics. One of the outstanding characteristics of a fluidized bed is that it tends to maintain a uniform temperature even with nonuniform heat release. On the basis of experimental research, the influence of the process's operational parameters on the obtained values of the bed's thermal conductivity has been analyzed. The results show direct dependence of thermal conductivity on the intensity of mixing, the degree of fluidization, and the size of particles. In the axial direction, the coefficients that have been treated have values a whole order higher than in the radial direction. Comparison of experimental research results with experimental results of other authors shows good agreement and the same tendency of thermal conductivity change. It is well known in the literature that the value of the heat transfer coefficient is the highest in the horizontal and the smallest in the vertical position of the heat exchange surface. Variation of heat transfer, depending on inclination angle is not examined in detail. The difference between the values of the relative heat transfer coefficient between vertical and horizontal heater position for all particle sizes reduces by approximately 15% with the increase of fluidization rate.

  14. The prevalence of molar incisor hypomineralisation in Northern England and its relationship to socioeconomic status and water fluoridation.

    Science.gov (United States)

    Balmer, Richard; Toumba, Jack; Godson, Jenny; Duggal, Monty

    2012-07-01

    Molar incisor hypomineralisation (MIH) is a condition which has significant implications for patients and service provision. The aim of this survey was to determine the prevalence of MIH in 12-year olds in Northern England and to consider the relationship with socioeconomic status and background water fluoridation. Twelve-year-old children were examined for the presence of MIH. Participating dentists were trained and calibrated in the use of the modified Developmental Defects of Enamel index. Children were examined at school under direct vision with the aid of a dental mirror. A diagnosis of MIH was attributed to a child if they had a demarcated defect in one or more of their first permanent molars. Of 4795 children that were selected, 3233 (67.4%) were examined. Overall prevalence of MIH was 15.9% (14.5-17.1%). There was an association between prevalence of MIH and deprivation quintiles with a positive correlation in the first 4 quintiles (P water fluoridation. © 2011 The Authors. International Journal of Paediatric Dentistry © 2011 BSPD, IAPD and Blackwell Publishing Ltd.

  15. The Effects of Various Running Inclines on Three-Segment Foot Mechanics and Plantar Fascia Strain

    Directory of Open Access Journals (Sweden)

    Sinclair Jonathan

    2014-12-01

    Full Text Available Purpose. There has yet to be a combined analysis of three-dimensional multi-segment foot kinematics and plantar fascia strain in running gait at various degrees of inclination. The aim of the current study was therefore to investigate the above during treadmill running at different inclines (0°, 5°, 10° and 15°. Methods. Twelve male participants ran at 4.0 m · s-1 in the four different inclinations. Three-dimensional kinematics of the foot segments and plantar fascia strain were quantified for each incline and contrasted using one-way repeated measures ANOVA. Results and conclusions. The results showed that plantar fascia strain increased significantly as a function of running incline. Given the projected association between plantar fascia strain and the aetiology of injury, inclined running may be associated with a greater incidence of injury to the plantar fascia.

  16. Strength Calculation of Inclined Sections of Reinforced Concrete Elements under Transverse Bending

    Science.gov (United States)

    Filatov, V. B.

    2017-11-01

    The authors propose a design model to determine the strength of inclined sections of bent reinforced concrete elements without shear reinforcement for the action of transverse force taking into account the aggregate interlock forces in the inclined crack. The calculated dependences to find out the components of forces acting in an inclined section are presented. The calculated dependences are obtained from the consideration of equilibrium conditions of the block over the inclined crack. A comparative analysis of the experimental values of the failure loads of the inclined section and the theoretical values obtained for the proposed dependencies and normative calculation methods is performed. It is shown that the proposed design model makes it possible to take into account the effect the longitudinal reinforcement percentage has on the inclined section strength, the element cross section height without the introduction of empirical coefficients which contributes to an increase in the structural safety of design solutions including the safety of high-strength concrete elements.

  17. The effect of crank position and backrest inclination on shoulder load and mechanical efficiency during handcycling

    NARCIS (Netherlands)

    Arnet, U.; van Drongelen, S.; Schlussel, M.; Lay, V.; van der Woude, L.H.V.; Veeger, H.E.J.

    2014-01-01

    Handbikes come in different models and setups, but only limited knowledge is available on the handbike-user interface. The aim of this study was to identify optimal handbike setups, assuming that in such a setup mechanical efficiency is high, while shoulder load is low. Thirteen subjects with a

  18. The effect of crank position and backrest inclination on shoulder load and mechanical efficiency during handcycling

    NARCIS (Netherlands)

    Arnet, U.; van Drongelen, S.; Schluessel, M.; Lay, V.; van der Woude, L. H. V.; Veeger, H. E. J.

    Handbikes come in different models and setups, but only limited knowledge is available on the handbike-user interface. The aim of this study was to identify optimal handbike setups, assuming that in such a setup mechanical efficiency is high, while shoulder load is low. Thirteen subjects with a

  19. Study Effect of Central Rectangular Perforation on the Natural Convection Heat Transfer in an Inclined Heated Flat Plate

    Directory of Open Access Journals (Sweden)

    Kadhum Audaa Jehhef

    2015-09-01

    Full Text Available Anumerical solutions is presented to investigate the effect of inclination angle (θ , perforation ratio (m and wall temperature of the plate (Tw on the heat transfer in natural convection from isothermal square flat plate up surface heated (with and without concentrated hole. The flat plate with dimensions of (128 mm length × (64 mm width has been used five with square models of the flat plate that gave a rectangular perforation of (m=0.03, 0.06, 0.13, 0.25, 0.5. The values of angle of inclination were (0o, 15o 30o 45o 60o from horizontal position and the values of wall temperature (50oC, 60 oC, 70 oC, 90 oC, 100oC. To investigate the temperature, boundary layer thickness and heat flux distributions; the numerical computation is carried out using a very efficient integral method to solve the governing equation. The results show increase in the temperature gradient with increase in the angle of inclination and the high gradient and high heat transfer coefficients located in the external edges of the plate, for both cases: with and without holed plate. There are two separation regions of heat transfer in the external edge and the internal edges. The boundary layer thickness is small in the external edge and high in the center of the plate and it decreases as the inclination angle of plate increases. Theoretical results are compared with previous result and it is found that the Nusslet numbers in the present study are higher by (22 % than that in the previous studies. And the results show good agreement in range of Raleigh number from 105 to 106.

  20. Convective flows of colloidal suspension in an inclined closed cell

    Energy Technology Data Exchange (ETDEWEB)

    Smorodin, Boris; Ishutov, Sergey [Department of Physics of Phase Transitions, Perm State University, Perm (Russian Federation); Cherepanov, Ivan, E-mail: bsmorodin@yandex.ru [Department of Radio Electronics and Information Security, Perm State University, Perm (Russian Federation)

    2016-12-15

    The nonlinear spatiotemporal evolution of convective flows is numerically investigated in the case of colloidal suspension filling an inclined closed cell heated from below. The bifurcation diagram (the dependency of the Nusselt number on the Rayleigh number) is obtained. The characteristics of the wave and steady patterns are investigated depending on heat intensity. The travelling wave changing travel direction and the non-regular oscillatory flow are found to be stable solutions within a certain interval of the Rayleigh number. Temporal Fourier decomposition is used together with other diagnostic tools to analyse the complex bifurcation and spatiotemporal properties caused by the interplay of the gravity-induced gradient of concentration and convective mixing of the fluid. It is shown that a more complex flow structure exists at a lower heating intensity (Rayleigh number). (paper)

  1. Friction and drag forces on spheres propagating down inclined planes

    Science.gov (United States)

    Tee, Yi Hui; Longmire, Ellen

    2017-11-01

    When a submerged sphere propagates along an inclined wall at terminal velocity, it experiences gravity, drag, lift, and friction forces. In the related equations of motion, the drag, lift and friction coefficients are unknown. Experiments are conducted to determine the friction and drag coefficients of the sphere over a range of Reynolds numbers. Through high speed imaging, translational and rotational velocities of spheres propagating along a glass plate are determined in liquids with several viscosities. The onset of sliding motion is identified by computing the dimensionless rotation rate of the sphere. Using drag and lift coefficients for Re friction coefficients are calculated for several materials. The friction coefficients are then employed to estimate the drag coefficient for 350 frictional force over this Re range. Supported by NSF (CBET-1510154).

  2. Method and apparatus for logging inclined earth boreholes

    International Nuclear Information System (INIS)

    Youmans, A.H.

    1981-01-01

    An improved technique is provided for comparing the velocity of an elongated well logging instrument traversing an inclined earth borehole with the playout velocity of the well logging cable at the earth's surface to control both the cable hoist drum rotation and the rate of movement of the subsurface instrument and thus insure cable playout is in equilibrium with the logging instrument movement. Method and apparatus are described for detecting any reduction in movement of the logging instrument through the borehole and for reducing the velocity of the logging cable playout in response thereto by reducing drum rotation. Further, when the velocity of cable playout slows to a preselected value, a monitoring circuit generates control signals which actuate a means of power attached to or integral with the logging instrument which, upon initiation, apply a force to move the logging instrument upward or downward within the borehole

  3. Simulation of Solar Radiation Incident on Horizontal and Inclined Surfaces

    Directory of Open Access Journals (Sweden)

    MA Basunia

    2012-12-01

    Full Text Available A computer model was developed to simulate the hourly, daily and monthly average of daily solar radiation on horizontal and inclined surfaces. The measured hourly and daily solar radiation was compared with simulated radiation, and favourable agreement was observed for the measured and predicted values on clear days. The measured and simulated monthly averages of total (diffuse and beam daily solar radiation were compared and a reasonable agreement was observed for a number of stations in Japan. The simulation showed that during the rice harvesting season, September to October, there is a daily average of 14.7 MJ/m2 of solar irradiation on a horizontal surface in Matsuyama, Japan. There is a similar amount of solar radiation on a horizontal surface during the major rice harvesting season, November to December, in Bangladesh. This radiation can be effectively utilized for drying rough rice and other farm crops.

  4. Study cast measurements in the assessment of incisor crowding among patients attending dental clinics in Abha city, Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Ibrahim Al-Shahrani

    2016-01-01

    Full Text Available Introduction: Demand for orthodontic treatment is increasing in Saudi Arabia. An observational study was planned to assess the incisor crowding in maxillary and mandibular arch among Saudi males and females reporting to different dental clinics in Abha city, Kingdom of Saudi Arabia (KSA. Materials and Methods: A cross-sectional study was conducted. Five hundred and thirty-two study casts of males and females aged between 16 and 35 years without a previous history of extraction of permanent teeth were included in the study. Labiolingual linear displacement of anatomic contact points of each maxillary and mandibular incisor from the adjacent tooth was measured. Right canine mesial aspect to the left canine mesial aspect was examined for five displacements. Results: There was a high prevalence of incisor crowding observed in the study population. Sixty-four percent (342 out of 532 casts showed bi-maxillary crowding, 14% (75 out of 352 showed mandibular, and 8.1% (43 out of 532 showed maxillary crowding. About 13.6% (72 out of 532 of the study population had well-aligned maxillary and mandibular incisors while 86.4% (460 out of 532 had some degree of incisor crowding. Females had more incisor crowding (48.5%-258 out of 532 than males (37.9%-202 out of 532. Conclusion: High prevalence of incisor crowding in Abha region reported in this study necessitates long-term planning and preventive measures for the adolescent population and treatment of the adult population of the Abha city, KSA.

  5. Molar-incisor hypomineralization (MIH) in a group of school-aged children in Benghazi, Libya.

    Science.gov (United States)

    Fteita, D; Ali, A; Alaluusua, S

    2006-06-01

    Molar-incisor hypomineralization (MIH) is common in many countries and it has significant impact on treatment need. The aim of the present study was to assess developmental enamel defects with an emphasis to MIH in children from four primary schools in Benghazi, Libya. Permanent first molars of a total of 378 (188 females) 7.0-8.9-year-old children were examined for demarcated opacities, diffuse opacities and hypoplasia in their schools using a portable light, a mirror, and a probe. A subgroup of children attending two of the four schools and having all incisors and first molars erupted (N = 154) was examined for enamel defects in these teeth. Eleven children (2.9%) had MIH. The mean value of demarcated opacities in their first molars was 1.5. MIH lesions were found only in 1.1% of the children's first molars (tooth prevalence) and all lesions were mild. Six children (1.6%) had diffuse opacities and 3 (0.8%) had hypoplastic defects in their first molars. Fourteen out of 154 children (9%) who had both incisors and molars examined had some kind of developmental enamel defect: 11 children (7.1%) had demarcated opacities, 3 (1.9%) had diffuse opacities, and none had hypoplasia. MIH was rare in Benghazi, Libya. The prevalence was clearly lower than in comparable studies performed in Italy or in Nordic countries, where, according to the earlier reports, MIH is seen in every fifth or sixth child. Our result may be valuable when so far mostly unknown etiology behind MIH is investigated.

  6. Are Hypomineralized Primary Molars and Canines Associated with Molar-Incisor Hypomineralization?

    Science.gov (United States)

    da Silva Figueiredo Sé, Maria Jose; Ribeiro, Ana Paula Dias; Dos Santos-Pinto, Lourdes Aparecida Martins; de Cassia Loiola Cordeiro, Rita; Cabral, Renata Nunes; Leal, Soraya Coelho

    2017-11-01

    The purpose of this study was to evaluate the prevalence of and relationship between hypomineralized second primary molars (HSPM) and hypomineralized primary canines (HPC) with molar-incisor hypomineralization (MIH) in 1,963 schoolchildren. The European Academy of Paediatric Dentistry (EAPD) criterion was used for scoring HSPM/HPC and MIH. Only children with four permanent first molars and eight incisors were considered in calculating MIH prevalence (n equals 858); for HSPM/HPC prevalence, only children with four primary second molars (n equals 1,590) and four primary canines (n equals 1,442) were considered. To evaluate the relationship between MIH/HSPM, only children meeting both criteria cited were considered (n equals 534), as was true of MIH/HPC (n equals 408) and HSPM/HPC (n equals 360; chi-square test and logistic regression). The prevalence of MIH was 14.69 percent (126 of 858 children). For HSPM and HPC, the prevalence was 6.48 percent (103 of 1,592) and 2.22 percent (32 of 1,442), respectively. A significant relationship was observed between MIH and both HSPM/HPC (PMIH based on HSPM was 6.31 (95 percent confidence interval [CI] equals 2.59 to 15.13) and for HPC was 6.02 (95 percent CI equals 1.08 to 33.05). The results led to the conclusion that both hypomineralized second primary molars and hypomineralized primary canines are associated with molar-incisor hypomineralization, because children with HSPM/HPC are six times more likely to develop MIH.

  7. Root resorption of permanent incisors during three months of active orthodontic treatment.

    Science.gov (United States)

    Batool, Iffat; Abbas, Hasnain; Abbas, Assad; Abbas, Iram

    2010-01-01

    Root resorption is one of the most common and undesirable sequelea of orthodontic treatment. The aim of this study was to evaluate the amount of root resorption in permanent incisors during 3 month active period of fixed orthodontic appliance therapy using periapical radiographs. Periapical radiographs of a total of 138 permanent teeth (n = 138, mandibular n1 = 52, maxillary n2 = 86) were evaluated for root resorption. All patients were treated with 3M MBT multi-bonded, pre-adjusted appliances with 0.022 inch slots. Initial levelling and alignment was achieved with 0.0175 inch co-axial wires. All four incisors (maxillary and mandibular) were measured for any change in root length. The change in root length between T0 (pre-treatment) and T1 (post-treatment) was measured in millimetres and expressed in terms of percentage of original root length. The mean pre treatment (T0) root length for the maxillary teeth (n1 = 62) was 19.27 +/- 2.86 mm and 20.01 +/- 2.57 mm for the mandibular teeth (n2 = 31). The post-treatment (T1) root length for the maxillary teeth was 18.96 +/- 2.85 mm and 19.49 +/- 2.4 mm for the mandibular teeth showing a mean resorption of 0.31 mm and 0.52 mm for the maxillary and mandibular teeth respectively. Root resorption was strongly correlated with active orthodontic appliance therapy with maxillary and mandibular incisors being most susceptible. It was found that root resorption can be detected even in the early levelling and alignment stages of orthodontic treatment.

  8. External apical root resorption in maxillary incisors in orthodontic patients: associated factors and radiographic evaluation

    International Nuclear Information System (INIS)

    Nanekrungsan, Kamonporn; Patanaporn, Virush; Janhom, Apirum; Korwanich, Narumanus

    2012-01-01

    This study was performed to evaluate the incidence and degree of external apical root resorption of maxillary incisors after orthodontic treatment and to evaluate particular associated factors related to external apical root resorption. The records and maxillary incisor periapical radiographs of 181 patients were investigated. Crown and root lengths were measured and compared on the pre- and post-treatment periapical radiographs. Crown length was measured from the center of the incisal edge to the midpoint of the cemento-enamel junction (CEJ). Root length was measured from the CEJ midpoint to the root apex. A correction factor for the enlargement difference was used to calculate root resorption. The periapical radiographs of 564 teeth showed that the average root resorption was 1.39±1.27 (8.24±7.22%) and 1.69±1.14 mm (10.16±6.78%) for the maxillary central and lateral incisors, respectively. The results showed that the dilacerated or pointed roots, maxillary premolar extraction cases, and treatment duration were highly significant factors for root resorption (p<0.001). Allergic condition was a significant factor at p<0.01. Age at the start of treatment, large overjet, and history of facial trauma were also factors significantly associated with root resorption (p<0.05). There was no statistically significant difference in root resorption among the factors of gender, overbite, tongue-thrusting habit, types of malocclusion, and types of bracket. These results suggested that orthodontic treatment should be carefully performed in pre-treatment extraction patients who have pointed or dilacerated roots and need long treatment duration.

  9. Prosthetic replacement vs space closure for maxillary lateral incisor agenesis: A systematic review.

    Science.gov (United States)

    Silveira, Giordani Santos; de Almeida, Natália Valli; Pereira, Daniele Masterson Tavares; Mattos, Cláudia Trindade; Mucha, José Nelson

    2016-08-01

    Defining the best treatment for maxillary lateral incisor agenesis is a challenge. Our aim in this study was to determine, with the evidence available in the literature, the best treatment for maxillary lateral incisor agenesis in the permanent dentition, evaluating the esthetic, occlusal (functional), and periodontal results between prosthetic replacement and orthodontic space closure. Electronic databases (CENTRAL, PubMed, Web of Science, Scopus, and LILACS) were searched in September 2014 and updated in January 2015, with no restriction on language or initial date. A manual search of the reference lists of the potential studies was performed. Risk of bias was assessed by the Newcastle Ottawa Scale. The search identified 2174 articles, of which 1196 were excluded because they were duplicates. Titles and abstracts of 978 articles were accessed, and 957 were excluded. In total, 21 articles were read in full, and 9 case-control studies were included after applying the inclusion and exclusion criteria. Data were extracted from the articles selected, and a table was compiled for comparison and analysis of the results. There were no randomization and blinding, and the risk of bias evaluation found gaps in compatibility and outcome domains in almost all selected studies. Tooth-supported dental prostheses of maxillary lateral incisor agenesis had worse scores in the periodontal indexes than did orthodontic space closure. Space closure is evaluated better esthetically than prosthetic replacements, and the presence or absence of a Class I relationship of the canines showed no relationship with occlusal function or with signs and symptoms of temporomandibular disorders. Copyright © 2016 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

  10. External apical root resorption in maxillary incisors in orthodontic patients: associated factors and radiographic evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Nanekrungsan, Kamonporn [Dept. of Dentistry, Overbrook Hospital, Chiang Rai (Thailand); Patanaporn, Virush; Janhom, Apirum; Korwanich, Narumanus [Dept. of Chiang Mai University, Chiang Mai (Thailand)

    2012-09-15

    This study was performed to evaluate the incidence and degree of external apical root resorption of maxillary incisors after orthodontic treatment and to evaluate particular associated factors related to external apical root resorption. The records and maxillary incisor periapical radiographs of 181 patients were investigated. Crown and root lengths were measured and compared on the pre- and post-treatment periapical radiographs. Crown length was measured from the center of the incisal edge to the midpoint of the cemento-enamel junction (CEJ). Root length was measured from the CEJ midpoint to the root apex. A correction factor for the enlargement difference was used to calculate root resorption. The periapical radiographs of 564 teeth showed that the average root resorption was 1.39{+-}1.27 (8.24{+-}7.22%) and 1.69{+-}1.14 mm (10.16{+-}6.78%) for the maxillary central and lateral incisors, respectively. The results showed that the dilacerated or pointed roots, maxillary premolar extraction cases, and treatment duration were highly significant factors for root resorption (p<0.001). Allergic condition was a significant factor at p<0.01. Age at the start of treatment, large overjet, and history of facial trauma were also factors significantly associated with root resorption (p<0.05). There was no statistically significant difference in root resorption among the factors of gender, overbite, tongue-thrusting habit, types of malocclusion, and types of bracket. These results suggested that orthodontic treatment should be carefully performed in pre-treatment extraction patients who have pointed or dilacerated roots and need long treatment duration.

  11. Initial forces and moments delivered by removable thermoplastic appliances during rotation of an upper central incisor.

    Science.gov (United States)

    Hahn, Wolfram; Engelke, Benjamin; Jung, Klaus; Dathe, Henning; Fialka-Fricke, Julia; Kubein-Meesenburg, Dietmar; Sadat-Khonsari, Reza

    2010-03-01

    To determine the forces and moments delivered to a maxillary central incisor during rotation by three different thermoplastic appliances with identical thickness. Five identical appliances were manufactured from each of three materials (Ideal Clear 1.0 mm, Erkodur 1.0 mm, Biolon 1.0 mm). An upper central incisor fixed in a measuring device was rotated around its central axis in 0.5-degree steps to +/-2.5 degrees, +/-5 degrees, and +/-7.5 degrees (equivalent to an activation of +/-0.17 mm, +/-0.34 mm, and +/-0.51 mm of the incisor edge) in the clockwise and anticlockwise directions with the respective appliance fixed in place. For statistical analysis, the moments Tz (rotation) and forces Fz (intrusion) were tested. Means and standard deviations for Tz and median and 25% and 75% quantiles for Fz were calculated. An analysis of variance (ANOVA) was performed. The minimal moment was determined at a rotation of -0.17 mm (-7.3 Nmm, +/-0.8), and the maximal moment at a deflection of -0.51 mm (-71.8 Nmm. +/-2.5) was recorded. The minimal value for Fz was measured at an activation of -0.17 mm (0.0 N), and the highest intrusive forces were evaluated for a rotation of -0.51 mm (-5.8 N). The particular material sometimes had a significant (P aligners, an intrusive force can also be observed. The direction of rotation, and the materials used all exert an influence on the force delivery properties of the appliance.

  12. Fracture resistance of upper central incisors restored with different posts and cores

    Directory of Open Access Journals (Sweden)

    Maryam Rezaei Dastjerdi

    2015-08-01

    Full Text Available Objectives To determine and compare the fracture resistance of endodontically treated maxillary central incisors restored with different posts and cores. Materials and Methods Forty-eight upper central incisors were randomly divided into four groups: cast post and core (group 1, fiber-reinforced composite (FRC post and composite core (group 2, composite post and core (group 3, and controls (group 4. Mesio-distal and bucco-lingual dimensions at 7 and 14 mm from the apex were compared to ensure standardization among the groups. Twelve teeth were prepared for crown restoration (group 4. Teeth in other groups were endodontically treated, decoronated at 14 mm from the apex, and prepared for posts and cores. Resin-based materials were used for cementation in groups 1 and 2. In group 3, composite was used directly to fill the post space and for core build-up. All samples were restored by standard metal crowns using glass ionomer cement, mounted at 135° vertical angle, subjected to thermomechanical aging, and then fractured using a universal testing machine. Kruskal-Wallis and Mann-Whitney U tests were used to analyze the data. Results Fracture resistance of the groups was as follows: Control (group 4 > cast post and core (group 1 > fiber post and composite core (group 2 > composite post and core (group 3. All samples in groups 2 and 3 fractured in restorable patterns, whereas most (58% in group 1 were non-restorable. Conclusions Within the limitations of this study, FRC posts showed acceptable fracture resistance with favorable fracture patterns for reconstruction of upper central incisors.

  13. A clinical study to evaluate the correlation between maxillary central incisor tooth form and face form in an Indian population.

    Science.gov (United States)

    Koralakunte, Pavankumar R; Budihal, Dhanyakumar H

    2012-09-01

    A study was performed to examine the correlation between maxillary central incisor tooth form and face form in males and females in an Indian population. The selection of prosthetic teeth for edentulous patients is a primary issue in denture esthetics, especially in the case of maxillary central incisors, which are the most prominent teeth in the arch. Two hundred dental students of Indian origin comprising 79 males and 121 females aged 18-28 years studying at Bapuji Dental College and Hospital were randomly selected as the study subjects. A standardized photographic procedure was used to obtain images of the face and the maxillary central incisors. The outline forms of the face and the maxillary right central incisor tooth were determined using a standardized method. The outline forms obtained were used to classify both face form and tooth form on the basis of visual and William's methods. The means were considered after evaluation by five prosthodontists, and the results were tabulated. Statistical analysis was performed using the chi-squared test for association and Z-test for equality of proportions. A correlation greater than 50% was observed between tooth form and face form by the visual method, compared with one of 31.5% by William's method. There was no highly defined correlation between maxillary central incisor tooth form and face form among the male and female Indian subjects studied.

  14. First records of talon cusps on baboon maxillary incisors argue for standardizing terminology and prompt a hypothesis of their formation.

    Science.gov (United States)

    Heaton, Jason L; Pickering, Travis Rayne

    2013-12-01

    Dental characters can provide vital clues for understanding intra- and intertaxonomic morphological variation and its underlying genetic and environmental components. However, the unambiguous identification of particular traits and their comparative study is often confounded by lack of consistent terminology in the relevant literature. This difficulty is exacerbated when the etiologies are not completely understood, as is the case with talon cusps. To date, research on talon cusps has focused on modern humans. In many instances, descriptions of talon cusps appear in clinical case studies focusing on their treatment and removal. What is lacking in those discussions, though, is a comparative framework, in which the occurrence of talon cusps in nonhuman primates, and possibly other mammals, is established and understood. Here, we report on a taloned upper central incisor of a wild baboon (Papio hamadryas ursinus) from South Africa. The anomalous incisor of this individual includes an exaggerated accessory cusp diagnosed as a Type II talon. Microcomputed tomographic and radiographic analyses show that the taloned cusp possesses enamel, dentin, and pulp. In addition, we identified an unclassifiable talon cusp on a central maxillary incisor of a baboon skull housed in the Smithsonian Institution's Natural History Museum collection. Our observations of talon cusps on baboon incisors demonstrate that, with regard to this phenomenon, systematic study of nonhuman primates is much needed, along with a consistent use of terminology in the anatomical and anthropological literature. Finally, we present a hypothesis of the formation of talon cusps on mammalian incisors. Copyright © 2013 Wiley Periodicals, Inc.

  15. A multidisciplinary treatment of congenitally missing maxillary lateral incisors: a 14-year follow-up case report

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    Renato Rodrigues de ALMEIDA

    2014-10-01

    Full Text Available Absence of the maxillary lateral incisor creates an aesthetic problem which can be managed in various ways. The condition requires careful treatment planning and consideration of the options and outcomes following either space closure or prosthetic replacement. Recent developments in restorative dentistry have warranted a re-evaluation of the approach to this clinical situation. Factors relating both to the patient and the teeth, including the presentation of malocclusion and the effect on the occlusion must be considered. The objective of this study was to describe the etiology, prevalence and alternative treatment modalities for dental agenesis and to present a clinical case of agenesis of the maxillary lateral incisors treated by the closure of excessive spaces and canine re-anatomization. A clinical case is presented to illustrate the interdisciplinary approach between orthodontics and restorative dentistry for improved esthetic results. In this report, the treatment of a girl with a Class II malocclusion of molars and canines with missing maxillary lateral incisors and convex facial profile is shown. Treatment was successfully achieved and included the space closure of the areas corresponding to the missing upper lateral incisors, through movement of the canines and the posterior teeth to mesial by fixed appliances as well as the canines transformation in the maxillary lateral incisors. This is a 14-year follow-up case report involving orthodontics and restorative dentistry in which pretreatment, posttreatment, and long-term follow-up records for the patient are presented.

  16. A multidisciplinary treatment of congenitally missing maxillary lateral incisors: a 14-year follow-up case report

    Science.gov (United States)

    de ALMEIDA, Renato Rodrigues; MORANDINI, Ana Carolina Faria; de ALMEIDA-PEDRIN, Renata Rodrigues; de ALMEIDA, Marcio Rodrigues; CASTRO, Renata Cristina Faria Ribeiro; INSABRALDE, Natalia Martins

    2014-01-01

    Absence of the maxillary lateral incisor creates an aesthetic problem which can be managed in various ways. The condition requires careful treatment planning and consideration of the options and outcomes following either space closure or prosthetic replacement. Recent developments in restorative dentistry have warranted a re-evaluation of the approach to this clinical situation. Factors relating both to the patient and the teeth, including the presentation of malocclusion and the effect on the occlusion must be considered. The objective of this study was to describe the etiology, prevalence and alternative treatment modalities for dental agenesis and to present a clinical case of agenesis of the maxillary lateral incisors treated by the closure of excessive spaces and canine re-anatomization. A clinical case is presented to illustrate the interdisciplinary approach between orthodontics and restorative dentistry for improved esthetic results. In this report, the treatment of a girl with a Class II malocclusion of molars and canines with missing maxillary lateral incisors and convex facial profile is shown. Treatment was successfully achieved and included the space closure of the areas corresponding to the missing upper lateral incisors, through movement of the canines and the posterior teeth to mesial by fixed appliances as well as the canines transformation in the maxillary lateral incisors. This is a 14-year follow-up case report involving orthodontics and restorative dentistry in which pretreatment, post-treatment, and long-term follow-up records for the patient are presented. PMID:25466480

  17. Comparative studies between mice molars and incisors are required to draw an overview of enamel structural complexity

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    MICHEL eGOLDBERG

    2014-09-01

    Full Text Available In the field of dentistry, the murine incisor has long been considered as an outstanding model to study amelogenesis. However, it clearly appears that enamel from wild type mouse incisors and molars presents several structural differences. In incisor, exclusively radial enamel is observed. In molars, enamel displays a high level of complexity since the inner part is lamellar whereas the outer enamel shows radial and tangential structures. Recently, the serotonin 2B receptor (5-HT2BR was shown to be involved in ameloblast function and enamel mineralization. The incisors from 5HT2BR knockout (KO mice exhibit mineralization defects mostly in the outer maturation zone and porous matrix network in the inner zone. In the molars, the mutation affects both secretory and maturation stages of amelogenesis since pronounced alterations concern overall enamel structures. Molars from 5HT2BR KO mice display reduction in enamel thickness, alterations of inner enamel architecture including defects in Hunter-Schreger Bands arrangements, and altered maturation of the outer radial enamel. Differences of enamel structure were also observed between incisor and molar from other KO mice depleted for genes encoding enamel extracellular matrix proteins.

  18. Compound odontoma associated with an unerupted rotated and dilacerated maxillary central incisor

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    Vinaya Kumar Kulkarni

    2011-01-01

    Full Text Available Odontomas are benign tumors containing various component tissues of teeth. They usually remain asymptomatic and are diagnosed on routine radiographs. Clinically, they are often associated with delayed eruption or impaction of permanent teeth and retained primary teeth. A case of compound odontoma in association with an unerupted, rotated and dilacerated maxillary permanent right central incisor in a 12-year-old boy is reported. Such combination is rare, making it an interesting case for reporting. We have also discussed the clinical features, diagnosis and treatment of such a condition.

  19. Management of endodontic-periodontic lesion of a maxillary lateral incisor with palatoradicular groove

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    Jayshree Ramakrishna Vishwas

    2014-01-01

    Full Text Available Presence of palatal radicular grooves are considered to be an important contributing factor to the development of localized periodontitis, as it favored the accumulation and proliferation of bacterial plaque deep into the periodontium. Pulp involvement could result due to the introduction of bacterial toxins through channels that existed between the root canal system and the groove. Early diagnosis, elimination of inflammation and correction of anatomic complications are the key to a favorable outcome for managing palatoradicular groove. Present report describes successful management with an interdisciplinary approach of maxillary lateral incisor with combined endodontic periodontic lesion associated with palatoradicular groove.

  20. Autoradiographic investigation of the effects of low-dose colchicine on dentinogenesis in rat incisors

    International Nuclear Information System (INIS)

    Oliveira Nogueira, T. de; Rossetini, S.M.

    1991-01-01

    Twelve wistar rats received 0.5 mg/kg colchicine (CLC) i.v. Three animals were sacrified 5 h, 24 h, 3 days and 7 days after the injection. Ninety minutes before sacrifice all animals received tritiated proline intraperitoneally. Autoradiograms of sections from the maxillary incisor were subjected to quantitative, and statistical analysis. These results revealed an increased secretory activity in the odontoblasts in the more incisal parts of the tooth, indicating a stimulatory effect of CLC on collagen production and secretion after 3 days. (author)

  1. Surgical and orthodontic management of fused maxillary central and lateral incisors in early mixed dentition stage.

    Science.gov (United States)

    Ramamurthy, Suresh; Satish, Ramaswamy; Priya, Kalidass

    2014-01-01

    Fusion is one of the developmental dental anomalies in which two adjacent teeth are joined at the crown level forming a single tooth with an enlarged crown. Fusion causes some clinical problems such as unaesthetic appearance, pain, caries, and malocclusion. The management of fusion often needs multidisciplinary approach to give best possible esthetic and functional outcome. This paper reports a case of 9-year-old boy with fused maxillary left central and lateral incisors who was treated with 2 × 4 fixed orthodontic appliances after surgical separation of fused teeth.

  2. Surgical and Orthodontic Management of Fused Maxillary Central and Lateral Incisors in Early Mixed Dentition Stage

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    Suresh Ramamurthy

    2014-01-01

    Full Text Available Fusion is one of the developmental dental anomalies in which two adjacent teeth are joined at the crown level forming a single tooth with an enlarged crown. Fusion causes some clinical problems such as unaesthetic appearance, pain, caries, and malocclusion. The management of fusion often needs multidisciplinary approach to give best possible esthetic and functional outcome. This paper reports a case of 9-year-old boy with fused maxillary left central and lateral incisors who was treated with 2×4 fixed orthodontic appliances after surgical separation of fused teeth.

  3. Skeletal class III camouflage by mandibular incisor extraction: A case report

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    Janardhanan Kumaresan

    2014-01-01

    Full Text Available Treatment planning in orthodontics plays a key role in determining the successful treatment of any kind of malocclusion. Skeletal class III malocclusions are generally difficult to treat because of the complex nature of the skeletal and dental manifestations they produce. Mild to moderate skeletal class III malocclusions sometimes have an acceptable facial profile where orthodontic camouflage is possible. In this case report, camouflage of a mild skeletal class III is done by the extraction of a single mandibular incisor, which helped in maintaining the profile of the patient and also in the correction of crowding in the mandibular anterior region.

  4. Revascularization for a necrotic immature permanent lateral incisor: a case report and literature review.

    Science.gov (United States)

    Kottoor, Jojo; Velmurugan, Natanasabapathy

    2013-07-01

    Revascularization is a valuable treatment in immature necrotic teeth that allows the continuation of root development. This article describes the successful revascularization treatment of an immature maxillary lateral incisor that was initially diagnosed with apical periodontitis. The tooth was asymptomatic and functional clinically and radiographically during the follow-up period of 5 years. The follow-up showed evidence of progressive thickening of the dentinal walls, development of root length and apical closure. The article also discusses the currently available literature regarding revascularization of immature permanent teeth. © 2012 John Wiley & Sons Ltd, BSPD and IAPD.

  5. Focal plane instrumentation: a very high resolution MWPC system for inclined tracks

    International Nuclear Information System (INIS)

    Bertozzi, W.; Hynes, M.V.; Sargent, C.P.; Creswell, C.; Dunn, P.C.; Hirsch, A.; Leitch, M.; Norum, B.; Rad, F.N.; Sasanuma, T.

    1977-01-01

    A focal plane system has been developed for the MIT energy-loss spectrometer. The arrival time information from adjacent wires of one MWPC (s=2mm), is used to trace particle trajectories with a position resolution of 120μm (2sigma) and an angular resolution of less than 17 mrad (2sigma). The tracks are inclined to the MWPC at about 45 0 . The readout uses 3 delay lines connected to successive sense wires in a cyclical pattern. Coarse wire positions are determined by differences and drift times by sums of signal arrival times at the ends of the delays lines. A Cherenkov counter provides a fiducial signal. Interpolation is independent of drift velocity since the drift is normal to the sense plane. A similar readout with a second chamber provides position information perpendicular to momentum plane. This information is used to correct on-line for focal plane curvatures and other spectrometer aberrations. Final momentum resolution is about 10 -4 . (Auth.)

  6. Numerical simulation and structural optimization of the inclined oil/water separator.

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    Liqiong Chen

    Full Text Available Improving the separation efficiency of the inclined oil/water separator, a new type of gravity separation equipment, is of great importance. In order to obtain a comprehensive understanding of the internal flow field of the separation process of oil and water within this separator, a numerical simulation based on Euler multiphase flow analysis and the realizable k-ε two equation turbulence model was executed using Fluent software. The optimal value ranges of the separator's various structural parameters used in the numerical simulation were selected through orthogonal array experiments. A field experiment on the separator was conducted with optimized structural parameters in order to validate the reliability of the numerical simulation results. The research results indicated that the horizontal position of the dispenser, the hole number, and the diameter had significant effects on the oil/water separation efficiency, and that the longitudinal position of the dispenser and the position of the weir plate had insignificant effects on the oil/water separation efficiency. The optimal structural parameters obtained through the orthogonal array experiments resulted in an oil/water separation efficiency of up to 95%, which was 4.996% greater than that realized by the original structural parameters.

  7. New inclination changing eclipsing binaries in the Magellanic Clouds

    Science.gov (United States)

    Juryšek, J.; Zasche, P.; Wolf, M.; Vraštil, J.; Vokrouhlický, D.; Skarka, M.; Liška, J.; Janík, J.; Zejda, M.; Kurfürst, P.; Paunzen, E.

    2018-01-01

    Context. Multiple stellar systems are unique laboratories for astrophysics. Analysis of their orbital dynamics, if well characterized from their observations, may reveal invaluable information about the physical properties of the participating stars. Unfortunately, there are only a few known and well described multiple systems, this is even more so for systems located outside the Milky Way galaxy. A particularly interesting situation occurs when the inner binary in a compact triple system is eclipsing. This is because the stellar interaction, typically resulting in precession of orbital planes, may be observable as a variation of depth of the eclipses on a long timescale. Aims: We aim to present a novel method to determine compact triples using publicly available photometric data from large surveys. Here we apply it to eclipsing binaries (EBs) in Magellanic Clouds from OGLE III database. Our tool consists of identifying the cases where the orbital plane of EB evolves in accord with expectations from the interaction with a third star. Methods: We analyzed light curves (LCs) of 26121 LMC and 6138 SMC EBs with the goal to identify those for which the orbital inclination varies in time. Archival LCs of the selected systems, when complemented by our own observations with Danish 1.54-m telescope, were thoroughly analyzed using the PHOEBE program. This provided physical parameters of components of each system. Time dependence of the EB's inclination was described using the theory of orbital-plane precession. By observing the parameter-dependence of the precession rate, we were able to constrain the third companion mass and its orbital period around EB. Results: We identified 58 candidates of new compact triples in Magellanic Clouds. This is the largest published sample of such systems so far. Eight of them were analyzed thoroughly and physical parameters of inner binary were determined together with an estimation of basic characteristics of the third star. Prior to our

  8. Loners, Groupies, and Long-term Eccentricity (and Inclination) Behavior: Insights from Secular Theory

    Science.gov (United States)

    Van Laerhoven, Christa L.

    2015-05-01

    Considering the secular dynamics of multi-planet systems provides substantial insight into the interactions between planets in those systems. Secular interactions are those that don't involve knowing where a planet is along its orbit, and they dominate when planets are not involved in mean motion resonances. These interactions exchange angular momentum among the planets, evolving their eccentricities and inclinations. To second order in the planets' eccentricities and inclinations, the eccentricity and inclination perturbations are decoupled. Given the right variable choice, the relevant differential equations are linear and thus the eccentricity and inclination behaviors can be described as a sum of eigenmodes. Since the underlying structure of the secular eigenmodes can be calculated using only the planets' masses and semi-major axes, one can elucidate the eccentricity and inclination behavior of planets in exoplanet systems even without knowing the planets' current eccentricities and inclinations. I have calculated both the eccentricity and inclination secular eigenmodes for the population of known multi-planet systems whose planets have well determined masses and periods. Using this catalog of secular character, I will discuss the prevalence of dynamically grouped planets ('groupies') versus dynamically uncoupled planets ('loners') and how this relates to the exoplanets' long-term eccentricity and inclination behavior. I will also touch on the distribution of the secular eigenfreqiencies.

  9. How do the substrate reaction forces acting on a gecko's limbs respond to inclines?

    Science.gov (United States)

    Wang, Zhouyi; Dai, Zhendong; Li, Wei; Ji, Aihong; Wang, Wenbao

    2015-02-01

    Locomotion is an essential character of animals, and excellent moving ability results from the delicate sensing of the substrate reaction forces (SRF) acting on body and modulating the behavior to adapt the motion requirement. The inclined substrates present in habitats pose a number of functional challenges to locomotion. In order to effectively overcome these challenges, climbing geckos execute complex and accurate movements that involve both the front and hind limbs. Few studies have examined gecko's SRF on steeper inclines of greater than 90°. To reveal how the SRFs acting on the front and hind limbs respond to angle incline changes, we obtained detailed measurements of the three-dimensional SRFs acting on the individual limbs of the tokay gecko while it climbed on an inclined angle of 0-180°. The fore-aft forces acting on the front and hind limbs show opposite trends on inverted inclines of greater than 120°, indicating propulsion mechanism changes in response to inclines. When the incline angles change, the forces exerted in the normal and fore-aft directions by gecko's front and hind limbs are reassigned to take full advantage of limbs' different roles in overcoming resistance and in propelling locomotion. This also ensures that weight acts in the angle range between the forces generated by the front and hind limbs. The change in the distribution of SRF with a change in the incline angle is directly linked to the favorable trade-off between locomotive maneuverability and stability.

  10. Variation of the Friction Coefficient for a Cylinder Rolling down an Inclined Board

    Science.gov (United States)

    Yan, Zixiang; Xia, Heming; Lan, Yueheng; Xiao, Jinghua

    2018-01-01

    A cylinder rolling down an inclined board is a commonly seen and interesting object to study and it is also easy to experiment with and model. Following what has become a popular practice, we use smartphones to measure the angular acceleration of a cylinder rolling down a plane of different inclining angles. The friction force deviates from the…

  11. Inclination and anteversion of Collum femoris in hip dysplasia and coxarthritis

    Energy Technology Data Exchange (ETDEWEB)

    Madsen, J. S.; Svalastoga, E. [Kongelige Veterinaer- og Landbohoejskole, Copenhagen (Denmark)

    1994-07-01

    Femoral neck angles were measured radiographically in 41 dogs examined for hip dysplasia. Steep femoral neck inclination was found to be a phenomenon of hip dysplasia and coxofemoral joint laxity. The altered biomechanics of a steep femoral neck inclination may be a factor in the pathogenesis of hip dysplasia and secondary osteoarthritis.

  12. An analytic solution of the static problem of inclined risers conveying fluid

    KAUST Repository

    Alfosail, Feras; Nayfeh, Ali H.; Younis, Mohammad I.

    2016-01-01

    We use the method of matched asymptotic expansion to develop an analytic solution to the static problem of clamped–clamped inclined risers conveying fluid. The inclined riser is modeled as an Euler–Bernoulli beam taking into account its self

  13. Surgical management of impacted incisors in associate with supernumerary teeth: a combine case report of spontaneous eruption and orthodontic extrusion.

    Science.gov (United States)

    Das, D; Misra, J

    2012-01-01

    Maxillary permanent incisors impaction is not a frequent case in dental practice, but its treatment is challenging because of its importance to facial esthetics. Supernumerary teeth are the main cause of impaction of upper incisors. Supernumerary teeth when present can cause both esthetic and pathologic problems. Early detection of such teeth is most important if complications are to be avoided. In this reported case, the orthopantamogram of a 9-year-old boy revealed two impacted supernumerary teeth in the maxillary anterior region, which was interfering with the eruption of the permanent central incisors. The impacted supernumerary teeth were surgically removed, 11 was repositioned in the arch as it was situated very high in the arch, close to the nasal floor. Twenty-one erupted spontaneously but orthodontic force was applied over 11 to bring it into the occlusion and alignment was achieved with 0.014 mm NiTi wire.

  14. Space Station Freedom assembly and operation at a 51.6 degree inclination orbit

    Science.gov (United States)

    Troutman, Patrick A.; Brewer, Laura M.; Heck, Michael L.; Kumar, Renjith R.

    1993-01-01

    This study examines the implications of assembling and operating Space Station Freedom at a 51.6 degree inclination orbit utilizing an enhanced lift Space Shuttle. Freedom assembly is currently baselined at a 220 nautical mile high, 28.5 degree inclination orbit. Some of the reasons for increasing the orbital inclination are (1) increased ground coverage for Earth observations, (2) greater accessibility from Russian and other international launch sites, and (3) increased number of Assured Crew Return Vehicle (ACRV) landing sites. Previous studies have looked at assembling Freedom at a higher inclination using both medium and heavy lift expendable launch vehicles (such as Shuttle-C and Energia). The study assumes that the shuttle is used exclusively for delivering the station to orbit and that it can gain additional payload capability from design changes such as a lighter external tank that somewhat offsets the performance decrease that occurs when the shuttle is launched to a 51.6 degree inclination orbit.

  15. Experimental study on flow pattern transitions for inclined two-phase flow

    Energy Technology Data Exchange (ETDEWEB)

    Kwak, Nam Yee; Lee, Jae Young [Handong Univ., Pohang (Korea, Republic of); Kim, Man Woong [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2007-07-01

    In this paper, experimental data on flow pattern transition of inclination angles from 0-90 are presented. A test section is constructed 2 mm long and I.D 1inch using transparent material. The test section is supported by aluminum frame that can be placed with any arbitrary inclined angles. The air-water two-phase flow is observed at room temperature and atmospheric condition using both high speed camera and void impedance meter. The signal is sampled with sampling rate 1kHz and is analyzed under fully-developed condition. Based on experimental data, flow pattern maps are made for various inclination angles. As increasing the inclination angels from 0 to 90, the flow pattern transitions on the plane jg-jf are changed, such as stratified flow to plug flow or slug flow or plug flow to bubbly flow. The transition lines between pattern regimes are moved or sometimes disappeared due to its inclined angle.

  16. Efficient light trapping in silicon inclined nanohole arrays for photovoltaic applications

    Science.gov (United States)

    Deng, Can; Tan, Xinyu; Jiang, Lihua; Tu, Yiteng; Ye, Mao; Yi, Yasha

    2018-01-01

    Structural design with high light absorption is the key challenge for thin film solar cells because of its poor absorption. In this paper, the light-trapping performance of silicon inclined nanohole arrays is systematically studied. The finite difference time domain method is used to calculate the optical absorption of different inclination angles in different periods and diameters. The results indicate that the inclined nanoholes with inclination angles between 5° and 45° demonstrate greater light-trapping ability than their counterparts of the vertical nanoholes, and they also show that by choosing the optimal parameters for the inclined nanoholes, a 31.2 mA/cm2 short circuit photocurrent density could be achieved, which is 10.25% higher than the best vertical nanohole system and 105.26% higher than bare silicon with a thickness of 2330 nm. The design principle proposed in this work gives a guideline for choosing reasonable parameters in the application of solar cells.

  17. Numerical Analysis of Aerodynamic Characteristics of the Finned Surfaces with Cross-inclined Fins

    Directory of Open Access Journals (Sweden)

    Lagutin A. E.

    2016-12-01

    Full Text Available This paper presents results of numerical research and analyses air-side hydraulic performance of tube bundles with cross inclined fins. The numerical simulation of the fin-tube heat exchanger was performed using the Comsol Femlab software. The results of modeling show the influence of fin inclination angle and tube pitch on hydraulic characteristics of finned surfaces. A series of numerical tests were carried out for tube bundles with different inclination angles (γ =900, 850, 650, 60, the fin pitch u=4 mm. The results indicate that tube bundles with cross inclined fins can significantly enhance the average integral value of the air flow rate in channel between fins in comparison with conventional straight fins. Aerodynamic processes on both sides of modificated channel between inclined fins were analyzed. The verification procedures for received results of numerical modeling with experimental data were performed.

  18. Augmented corticotomy-assisted surgical orthodontics decompensates lower incisors in Class III malocclusion patients.

    Science.gov (United States)

    Wang, Bo; Shen, Guofang; Fang, Bing; Yu, Hongbo; Wu, Yong; Sun, Liangyan

    2014-03-01

    To quantitatively evaluate lower incisor decompensation and the surrounding periodontal region after augmented corticotomy-assisted surgical orthodontics in patients with Class III malocclusion. This prospective study enrolled patients with severe Class III malocclusion who underwent augmented corticotomy in the lower anterior region before orthodontic surgery. Cone-beam computed tomograms and lateral cephalograms were obtained before treatment (T0), after presurgical orthodontic treatment (T1), and at removal of the orthodontic surgical appliances (T2). Repeated measures analysis of variance was used to compare variables at each time point: root length (RL), anterior vertical alveolar bone level at the labial side (AVBL), posterior vertical alveolar bone level at the lingual side (PVBL), labial alveolar bone thickness at the apex (LA), lingual alveolar bone thickness at the apex (LP), and angle of the incisor to the mandibular plane (L1-MP). In the 8 subjects studied, RL was maintained from T0 to T2 (P > .05), whereas AVBL and PVBL increased from T0 to T1 (P .05). LP decreased from T0 to T1 (P lower anterior region in patients with Class III malocclusion. Copyright © 2014 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  19. Perception of molar-incisor hypomineralisation (MIH) by Iraqi dental academics.

    Science.gov (United States)

    Ghanim, Aghareed; Morgan, Michael; Mariño, Rodrigo; Manton, David; Bailey, Denise

    2011-07-01

    The understanding and detection of molar-incisor hypomineralisation (MIH) is linked to its recognition by clinicians. No study has investigated dental clinicians' level of perception regarding MIH in the Middle East region including Iraq. To determine the perception of Iraqi academic clinicians about MIH prevalence, severity and aetiological factors. A questionnaire, based on previous European and Australian/New Zealand studies was administered to the academic dental staff of Mosul University. A response rate of 77.7% was reported. General dental practitioners represented 30.8% of the total respondents, whilst 65.1% were dentists with post-graduate qualification. The majority of the respondents (81.2%) encountered MIH in their clinical activities and 37.3% of them identified that the prevalence appeared to have increased in recent years. Fewer than half of the respondents observed MIH affected teeth on a monthly basis. The condition was less commonly seen in primary second molars than the first permanent molars. A variation in views was recorded about MIH specific aetiological factor/s. Respondents advocated the need for clinical training regarding MIH-aetiological and therapeutic fields. Molar-incisor hypomineralisation is a condition commonly diagnosed by Iraqi dental academics. No apparent consensus existed between the general and specialist dentists regarding the anticipated prevalence, severity and aetiology of this condition. © 2011 The Authors. International Journal of Paediatric Dentistry © 2011 BSPD, IAPD and Blackwell Publishing Ltd.

  20. Drugs related to the etiology of molar incisor hypomineralization: A systematic review.

    Science.gov (United States)

    Serna, Clara; Vicente, Ascensión; Finke, Christian; Ortiz, Antonio J

    2016-02-01

    Molar incisor hypomineralization (MIH) is an idiopathic syndrome that has been associated with several etiologic factors. The authors' objective was to systematically review studies in which the investigators had studied how the etiology of MIH was related to medication intake. The search covered a period from January 1, 1965, to September 29, 2014. The search revealed 1,042 articles, to which the authors applied eligibility criteria and selected 20 studies for review. The authors considered 9 of the 20 studies to be high quality. The drugs used in these studies were chemotherapeutic drugs, antibiotics, asthma drugs, antiepileptic drugs, antiviral drugs, antifungal drugs, and antiparasitic drugs. Two reviewers independently performed risk-of-bias assessment and data extraction. The investigators of all of the studies had reported enamel defects, but only 2 sets of investigators had used the term "molar incisor hypomineralization." Owing to the different methodologies used by the investigators of the selected studies, the authors could not perform a meta-analysis of the study results. More well-designed prospective studies are needed to clarify the relationship between MIH and medication. It would be convenient to establish a preventive protocol in patients with a potential risk of developing MIH to avoid the complications that are characteristic of this disease. Copyright © 2016 American Dental Association. Published by Elsevier Inc. All rights reserved.

  1. [Autotransplantation of a maxillary incisor and orthodontic care: a case study].

    Science.gov (United States)

    Charpentier, Valentine; Makaremi, Masrour; Brondeau, François de

    2017-12-01

    Severely impacted teeth with atypical root anatomy do not respond well to orthodontic traction after surgical exposure. Consequently, they are often removed, but replacing them with dental prostheses can prove difficult in patients who are still growing. Thus, autotransplantation seems to be the only way to preserve a natural tooth and the alveolar bone. An upper central incisor impacted in the region of the nasal cavities with an open apex was diagnosed in an 8.5-year-old female patient. The tooth displayed a curved root pressed against the maxillary cortical bone preventing orthodontic traction treatment. Through this clinical case involving autotransplantation of a maxillary incisor report and a review of the literature, this article explores the indications and exposes the different stages of this orthodontic-surgical protocol. In this case, autotransplantation enabled restoration of maxillary arch continuity. After two years of orthodontic treatment, the bone reconstruction of the extraction site was very satisfactory. The benefits of this technique and the precautions to be taken are discussed as well as the various protocols. The increasing success rate of this surgical procedure makes it possible to consider it as a protocol for the future. © EDP Sciences, SFODF, 2017.

  2. Correction of a Severely Rotated Maxillary Incisor by Elastics in Mixed Dentition Complicated by a Mesiodens.

    Science.gov (United States)

    Sidiq, Mohsin; Yousuf, Asif; Bhat, Manohar; Sharma, Rajesh; Bhargava, Neha; Ganta, Shravani

    2015-01-01

    The aim of this case study was to report a potentially convenient approach instead of a conventional orthodontic procedure for correcting severe rotation of anterior tooth of an 11-year-old Indian boy, with a mixed dentition class I malocclusion. The child reported seeking treatment for severely rotated upper right central incisor with mesiodens and a single tooth crossbite. The supernumerary tooth was first extracted and bondable buttons were placed on the rotated tooth, an appliance composed of a removable plate with Adam's clasp with distal extension and a loop for engagement of elastics was delivered. Circumferential supracrestal fibrotomy was performed on the corrected derotated tooth. Then, Hawley's appliance with a z-spring and posterior bite plane was fabricated and placed for correction of crossbite. Thus, this removable appliance can be a simplified and a cost-effective treatment alternative for derotation of anterior tooth, especially during the mixed dentition period. How to cite this article: Sidiq M, Yousuf A, Bhat M, Sharma R, Bhargava N, Ganta S. Correction of a Severely Rotated Maxillary Incisor by Elastics in Mixed Dentition Complicated by a Mesiodens. Int J Clin Pediatr Dent 2015;8(3):234-238.

  3. Missing upper incisors: a retrospective study of orthodontic space closure versus implant.

    Science.gov (United States)

    Jamilian, Abdolreza; Perillo, Letizia; Rosa, Marco

    2015-02-25

    The aim of this retrospective study was to compare the esthetic, periodontal, and functional outcomes of orthodontic space closure versus implant substitution in patients with missing maxillary incisors 5 years after completion of treatment. The study group consisted of ten patients treated with orthodontic space closure (six males, four females, mean age 19 ± 2.1 years at the completion of treatment) and ten patients treated with implant insertion (five males, five females, mean age 20 ± 1.4 years at the time of implant insertion). Tooth mobility, plaque index, probing depth, infraocclusion, open gingival embrasure (black triangle), and temporomandibular joint function were recorded at the 5.6 years follow-up. Self-perceived dental esthetic appearance was also evaluated through a visual analog scale (VAS) questionnaire. T-test was used to evaluate the data. All patients were equally satisfied with the appearance of their teeth 5.6 ± 0.4 years after the completion of treatment. No statistically significant differences were found in relation to the VAS scores of the subjects (P Orthodontic space closure and implant of missing maxillary incisors produced similar, well-accepted esthetic results. None of the treatments impaired temporomandibular joint function. Nevertheless, infraocclusion was evident in implant patients. Space closure patients also showed better periodontal health in comparison with implant patients.

  4. Routine treatment of bilateral aplasia of upper lateral incisors by orthodontic space closure without mandibular extractions.

    Science.gov (United States)

    Zimmer, Bernd; Seifi-Shirvandeh, Nasrin

    2009-06-01

    This study aimed to gather statistically validated information on the changes in orthodontic variables in patients with bilateral upper lateral incisor aplasia treated with isolated orthodontic space closure. Data were collected from 25 (15 females, 10 males) consecutively treated, unselected adolescents [mean age at the end of treatment 16.4 years, standard deviation (SD) 1.3] after orthodontic space closure using push-and-pull mechanics (PPM). The changes in the relevant parameters were determined by comparing baseline and final lateral headfilms and casts. Following verification of normal distribution by means of a Kolmogorov-Smirnov test, a two-tailed t-test for related data was performed. SNA, ANB, OcP-NL, OcP-ML, upper space balance, overbite, overjet, bilateral molar relationship, and L1-NB changed significantly (P orthodontic space closure for bilateral upper lateral incisor aplasia using PPM can be regarded as a valid alternative to prosthetic solutions. Long-term use of Class III elastics does not lead to significant changes in relevant orthodontic parameters.

  5. Bursting pressure of autofrettaged cylinders with inclined external cracks

    International Nuclear Information System (INIS)

    Seifi, Rahman; Babalhavaeji, Majid

    2012-01-01

    Autofrettaging a pressure vessel improves its pressure capacity. This is reliable if there isn’t any crack or other type of flaws. In this paper, the effects of external surface cracks on bursting pressure of autofrettaged cylinders are studied. It is observed that bursting pressure decreases considerably (up to 30%) due to external cracks in the cylinders without autofrettage. This reduction increases for high levels of the applied autofrettage. External axial cracks have more effects than inclined cracks. Comparing experimental and numerical results show that the numerical methods can acceptably predict the bursting pressure of the autofrettaged cracked cylinders. These predictions are valid when the fracture parameter (J-Integral) is calculated from the modified equation that takes into account the effects of residual stresses. - Highlights: ► Modified J-Integral can be used for study of autofrettaged cracked cylinders. ► External axial cracks reduce considerably the pressure capacity of cylinders. ► External circumferential cracks have not considerable effects on bursting pressure. ► Autofrettage has contrary effects on external crack in compared with internal crack.

  6. Bursting pressure of autofrettaged cylinders with inclined external cracks

    Energy Technology Data Exchange (ETDEWEB)

    Seifi, Rahman, E-mail: rseifi@basu.ac.ir [Mechanical Engineering Department, Faculty of Engineering, Bu-Ali Sina University, Hamedan (Iran, Islamic Republic of); Babalhavaeji, Majid [Mechanical Engineering Department, Faculty of Engineering, Bu-Ali Sina University, Hamedan (Iran, Islamic Republic of)

    2012-01-15

    Autofrettaging a pressure vessel improves its pressure capacity. This is reliable if there isn't any crack or other type of flaws. In this paper, the effects of external surface cracks on bursting pressure of autofrettaged cylinders are studied. It is observed that bursting pressure decreases considerably (up to 30%) due to external cracks in the cylinders without autofrettage. This reduction increases for high levels of the applied autofrettage. External axial cracks have more effects than inclined cracks. Comparing experimental and numerical results show that the numerical methods can acceptably predict the bursting pressure of the autofrettaged cracked cylinders. These predictions are valid when the fracture parameter (J-Integral) is calculated from the modified equation that takes into account the effects of residual stresses. - Highlights: Black-Right-Pointing-Pointer Modified J-Integral can be used for study of autofrettaged cracked cylinders. Black-Right-Pointing-Pointer External axial cracks reduce considerably the pressure capacity of cylinders. Black-Right-Pointing-Pointer External circumferential cracks have not considerable effects on bursting pressure. Black-Right-Pointing-Pointer Autofrettage has contrary effects on external crack in compared with internal crack.

  7. Stability of film boiling on inclined plates and spheres

    Science.gov (United States)

    Aursand, Eskil; Hammer, Morten; Munkejord, Svend Tollak; Müller, Bernhard; Ytrehus, Tor

    2017-11-01

    In film boiling, a continuous sub-millimeter vapor film forms between a liquid and a heated surface, insulating the two from each other. While quite accurate steady state solutions are readily obtained, the intermediate Reynolds numbers can make transient analysis challenging. The present work is a theoretical study of film boiling instabilities. We study the formation of travelling waves that are a combination of Kelvin-Helmholtz and the Rayleigh-Taylor instabilities. In particular, we study how the nature of this process depends on the Reynolds number, the Bond number, and the inclination of the submerged heated plate. In addition we extend the analysis to the case of a submerged heated sphere. Modelling of the transient dynamics of such films is important for answering practical questions such as how instabilities affect the overall heat transfer, and whether they can lead to complete film boiling collapse (Leidenfrost point). This work has been financed under the MAROFF program. We acknowledge the Research Council of Norway (244076/O80) and The Gas Technology Centre NTNU-SINTEF (GTS) for support.

  8. Changing predictions, stable recognition: Children's representations of downward incline motion.

    Science.gov (United States)

    Hast, Michael; Howe, Christine

    2017-11-01

    Various studies to-date have demonstrated children hold ill-conceived expressed beliefs about the physical world such as that one ball will fall faster than another because it is heavier. At the same time, they also demonstrate accurate recognition of dynamic events. How these representations relate is still unresolved. This study examined 5- to 11-year-olds' (N = 130) predictions and recognition of motion down inclines. Predictions were typically in error, matching previous work, but children largely recognized correct events as correct and rejected incorrect ones. The results also demonstrate while predictions change with increasing age, recognition shows signs of stability. The findings provide further support for a hybrid model of object representations and argue in favour of stable core cognition existing alongside developmental changes. Statement of contribution What is already known on this subject? Children's predictions of physical events show limitations in accuracy Their recognition of such events suggests children may use different knowledge sources in their reasoning What the present study adds? Predictions fluctuate more strongly than recognition, suggesting stable core cognition But recognition also shows some fluctuation, arguing for a hybrid model of knowledge representation. © 2017 The British Psychological Society.

  9. Restoration of an intruded maxillary central incisor with a uniquely designed dowel and core restoration: a case report.

    Science.gov (United States)

    Polat, Zelal Seyfioğlu; Tacir, Ibrahim Halil

    2007-01-01

    This article describes the restoration of an intruded root using a custom-made metal dowel and metal-ceramic veneer core restoration. The treatment plan for this patient consisted of restoring the missing esthetics and eliminating psychological trauma by utilizing the root of the intruded maxillary left central incisor to replace both missing central incisor crowns. This treatment will preserve space and bone until the patient is old enough for another prosthodontic restoration to be considered. As the lost fragments were not recovered, we considered this restoration of the intruded root to be the best therapeutic option, considering the effect on the patient's psyche. The patient was satisfied with the final result.

  10. Computed tomographic method for measurement of inclination angles and motion of the sacroiliac joints in German Shepherd Dogs and Greyhounds.

    Science.gov (United States)

    Saunders, Fritha C; Cave, Nick J; Hartman, Karl M; Gee, Erica K; Worth, Andrew J; Bridges, Janis P; Hartman, Angela C

    2013-09-01

    To develop an in vivo CT method to measure inclination angles and motion of the sacroiliac joints in dogs of performance breeds. 10 German Shepherd Dogs and 12 Greyhounds without signs of lumbosacral region pain or neurologic problems. CT of the ilium and sacrum was performed in flexed, neutral, and extended hind limb positions. Lines were drawn on volume-rendered images acquired in the flexed and extended positions to measure motion of the ilia relative to the sacra. Inclination angles of the synovial and ligamentous components of the sacroiliac joints were measured on transverse-plane CT images acquired at cranial and caudal locations. Coefficients of variance of measurements were calculated to determine intraobserver variability. Coefficients of variance of measurements ranged from 0.17% to 2.45%. A significantly higher amount of sacroiliac joint rotational motion was detected for German Shepherd Dogs versus Greyhounds. The cranial synovial joint component had a significantly more sagittal orientation in German Shepherd Dogs versus Greyhounds. No significant differences were detected between breeds for x- or y-axis translational motion or caudal synovial or ligamentous joint component inclination angles. The small amounts of sacroiliac joint motion detected in this study may buffer high-frequency vibrations during movement of dogs. Differences detected between breeds may be associated with the predisposition of German Shepherd Dogs to develop lumbosacral region signs of pain, although the biological importance of this finding was not determined. Future studies are warranted to compare sacroiliac joint variables between German Shepherd Dogs with and without lumbosacral region signs of pain.

  11. Analysis of the relationship between occlusal and clinical parameters and the need for incisor reduction in confined horses - a retrospective study

    Directory of Open Access Journals (Sweden)

    Luiz Fernando Rapp de Oliveira Pimentel

    2014-11-01

    Full Text Available The purpose of this retrospective study was to evaluate the relationship between occlusal and clinical parameters and the need for incisor shortening in horses. It was based on the retrospective analysis of the dental charts of 75 confined horses. Body condition score, shape of incisors, presence of dysmastication, excursion to molar contact (EMC distance before and after cheek teeth occlusal adjustment were evaluated. History of difficult to riding, dysmastication and digestive problems was also considered. The initial measurement of lateral excursion to molar contact (EMC revealed incisor occlusal surface abnormalities in 45 (60% horses and long incisors (EMC>15mm in five (6.6% horses. Considering clinical examination and history data the need for reduction of incisor length was significant when EMC exceeded 15mm (P<0.0001 and when based on dental shape, clinical history of dysmastication and/or digestive problems or body condition score was also significant (P<0.05. In confined horses, the decision to shorten and align the incisor teeth should be based on observation and history of dysmastication and digestive problems, body condition score, incisors shape and EMC distance. The need for incisor reduction should be determined before dental intervention and reassessed following cheek teeth oclusal adjustment

  12. Management of a Two-rooted Maxillary Central Incisor Using Cone-beam Computed Tomography: Importance of Three-dimensional Imaging

    Directory of Open Access Journals (Sweden)

    Saurabh Kumar Gupta

    2015-09-01

    Full Text Available We report a rare case of a two-rooted maxillary central incisor, stressing the importance of three-dimensional imaging in treatment planning and conservative approach of management. Endodontic treatment of this central incisor was carried out with a successful outcome.

  13. A new 2 D bracket positioning gauge

    Directory of Open Access Journals (Sweden)

    Bhuwan Saklecha

    2017-01-01

    Full Text Available Bracket positioning is the basic premise of pre-adjusted system, which allows the teeth to be placed with a straight wire into an occlusal contact with an excellent mesiodistal inclination (tip and excellent faciolingual inclination (torque. Improper bracket placement may lead to poorly placed teeth and necessitate bracket repositioning and archwire adjustments. This can lead to an increased treatment time or poor occlusion. Therefore, a bracket positioning gauge has been designed using both the planes and evaluated for its accuracy in bonding of brackets. It was found that the gauge not only helped in the placement of brackets accurately, but also reduced chairside time.

  14. Turbulent mixed convection in vertical and inclined flat channels with aiding flows

    Energy Technology Data Exchange (ETDEWEB)

    Poskas, P.; Vilemas, J.; Adomaitis, J.E.; Bartkus, G.

    1995-09-01

    This paper presents an experimental study of turbulent mixed convection heat transfer for aiding flows in a vertical ({phi}=90{degrees}), inclined ({phi}=60{degrees},30{degrees}), and horizontal ({phi}=0{degrees}) flat channels with symmetrical heating and a ratio of height h to width b of about 1:10 and with length about 4 m (x/2h about 44). The study covered Re from 4x10{sup 3} to 5x10{sup 4} and Gr{sub q} from 5x10{sup 7}to 3x10{sup 10}. For the upper wall, a region of impaired heat transfer was found for all angular positions (from vertical to horizontal) and for bottom wall the augmentation of heat transfer in comparison to forced convection was revealed in the region of {phi}=0{degrees}-60{degrees}. Different characteristic buoyancy parameters were found for regions of impaired and enhanced heat transfer. General relations are suggested to predict the heat transfer for fully-developed-flow conditions and different angular positions.

  15. Orthodontic Treatment of Maxillary Incisors with Severe Root Resorption Caused by Bilateral Canine Impaction in a Class II Division 1 Patient.

    Science.gov (United States)

    Chang, Na-Young; Park, Jae Hyun; Lee, Mi-Young; Cho, Jin-Woo; Cho, Jin-Hyoung; An, Ki-Yong; Chae, Jong-Moon

    2016-01-01

    This case report shows the successful alignment of bilateral impacted maxillary canines. A 12-year-old male with the chief complaint of the protrusion of his maxillary anterior teeth happened to have bilateral maxillary canine impaction on the labial side of his maxillary incisors. Four maxillary incisors showed severe root resorption because of the impacted canines. The patient was diagnosed as skeletal Class II malocclusion with proclined maxillary incisors. The impacted canine was carefully retracted using sectional buccal arch wires to avoid further root resorption of the maxillary incisors. To distalize the maxillary dentition, two palatal miniscrews were used. After 25 months of treatment, the maxillary canines were well aligned without any additional root resorption of the maxillary incisors.

  16. Evaluation of buccolingual inclination of posterior teeth in different facial patterns using computed tomography

    Directory of Open Access Journals (Sweden)

    Suomo Mitra

    2011-01-01

    Full Text Available Background and Objective: Buccolingual inclination of teeth is an essential factor in establishing good occlusion. The objective of this study was to evaluate the buccolingual inclination of molar teeth in different vertical skeletal patterns by using computed tomography scans. Materials and Methods: Coronal section of the jaws obtained from computed tomograms were used to measure the buccolingual inclination of the long axis of the molars relative to their skeletal base. Forty male adult individuals with class I dental occlusion were selected. They were classified as short (Group 1, average (Group II, and long faced (Group III as per their skeletal patterns measured by GoGn-SN, FH-MP, Y-axis and facial height index in cephalograms. Statistical Analysis: ANOVA and Tukey HSD tests were applied to calculate if there were any significant differences in the mean molar inclination between the groups. Pearson′s coefficients of correlation were calculated between the facial parameters and tooth inclination. Results: The differences in the mean molar inclination between the short, average, and long faced groups is significant for mandibular 1 st and 2 nd molars and maxillary 2 nd molars. Conclusion: Variations in mean molar inclination values are observed between short, average, and long faced groups.

  17. Treating domestic sewage by Integrated Inclined-Plate-Membrane bio-reactor

    Science.gov (United States)

    Song, Li Ming; Wang, Zi; Chen, Lei; Zhong, Min; Dong, Zhan Feng

    2017-12-01

    Membrane fouling shorten the service life of the membrane and increases aeration rate for membrane surface cleaning. Two membrane bio-reactors, one for working and another for comparing, were set up to evaluate the feasibility of alleviating membrane fouling and improving wastewater treatment efficiency by integrating inclined-plate precipitation and membrane separation. The result show that: (1) Inclined-plate in reactor had a good effect on pollutant removal of membrane bioreactor. The main role of inclined-plate is dividing reactor space and accelerating precipitation. (2) Working reactor have better performance in COD, TN and TP removal, which can attribute to that working reactor (integrated inclined-plate-Membrane bioreactor) takes both advantages of membrane separation and biological treatment. When influent COD, TP and TN concentration is 163-248 mg/L, 2.08-2.81 mg/L and 24.38-30.49 mg/L in working reactor, effluent concentration is 27-35 mg/L, 0.53-0.59 mg/L and 11.28-11.56 mg/L, respectively. (3) Membrane fouling was well alleviated in integrated inclined-plate-Membrane bioreactor, and membrane normal service time is significantly longer than that in comparing reactor, which can attribute to accelerating precipitation of inclined-plate. In summary, integrated inclined-plate-Membrane bioreactor is a promising technology to alleviating membrane fouling and improving wastewater treatment efficiency, having good performance and bright future in application.

  18. Revealing strong bias in common measures of galaxy properties using new inclination-independent structures

    Science.gov (United States)

    Devour, Brian M.; Bell, Eric F.

    2017-06-01

    Accurate measurement of galaxy structures is a prerequisite for quantitative investigation of galaxy properties or evolution. Yet, the impact of galaxy inclination and dust on commonly used metrics of galaxy structure is poorly quantified. We use infrared data sets to select inclination-independent samples of disc and flattened elliptical galaxies. These samples show strong variation in Sérsic index, concentration and half-light radii with inclination. We develop novel inclination-independent galaxy structures by collapsing the light distribution in the near-infrared on to the major axis, yielding inclination-independent 'linear' measures of size and concentration. With these new metrics we select a sample of Milky Way analogue galaxies with similar stellar masses, star formation rates, sizes and concentrations. Optical luminosities, light distributions and spectral properties are all found to vary strongly with inclination: When inclining to edge-on, r-band luminosities dim by >1 magnitude, sizes decrease by a factor of 2, 'dust-corrected' estimates of star formation rate drop threefold, metallicities decrease by 0.1 dex and edge-on galaxies are half as likely to be classified as star forming. These systematic effects should be accounted for in analyses of galaxy properties.

  19. The Interaction between Personality, Social Network Position and Involvement in Innovation Process

    NARCIS (Netherlands)

    E. Dolgova (Evgenia); W. van Olffen (Woody); F.A.J. van den Bosch (Frans); H.W. Volberda (Henk)

    2010-01-01

    textabstractAbstract This dissertation proposal investigates how personality and individuals’ social network position affect individuals’ involvement into the innovation process. It posits that people would feel inclined to become involved into the different phases of the innovation process

  20. In vitro fracture resistance of endodontically treated central incisors with varying ferrule heights and configurations.

    Science.gov (United States)

    Tan, Philip L B; Aquilino, Steven A; Gratton, David G; Stanford, Clark M; Tan, Swee Chian; Johnson, William T; Dawson, Deborah

    2005-04-01

    The in vitro effectiveness of a uniform circumferential ferrule has been established in the literature; however, the effect of a nonuniform circumferential ferrule height on fracture resistance is unknown. This in vitro study investigated the resistance to static loading of endodontically treated teeth with uniform and nonuniform ferrule configurations. Fifty extracted intact maxillary human central incisors were randomly assigned to 1 of 5 groups: CRN, no root canal treatment (RCT), restored with a crown; RCT/CRN, no dowel/core, restored with a crown; 2 FRL, 2-mm ferrule, cast dowel/core and crown; 0.5/2 FRL, nonuniform ferrule (2 mm buccal and lingual, 0.5 mm proximal), cast dowel/core and crown; and 0 FRL, no ferrule, cast dowel/core and crown. The teeth were prepared to standardized specifications and stored for 72 hours in 100% humidity prior to testing. Testing was conducted with a universal testing machine with the application of a static load, and the load (N) at failure was recorded. Statistical analysis was performed with a 1-way analysis of variance and the Tukey Honestly Significant Difference test (alpha=.05). The mode of fracture was noted by visual inspection for all specimens. There was strong evidence of group differences in mean fracture strength ( P <.0001). Following adjustment for all pairwise group comparisons, it was found that the lack of a ferrule resulted in a significantly lower mean fracture strength (0 FRL: 264.93 +/- 78.33 N) relative to all other groups. The presence of a nonuniform (0.5 to 2-mm vertical height) ferrule (0.5/2 FRL: 426.64 +/- 88.33 N) resulted in a significant decrease ( P =.0001) in mean fracture strength when compared with the uniform 2-mm vertical ferrule (2 FRL: 587.23 +/- 110.25 N), the group without RCT (CRN: 583.67 +/- 86.09 N), and the RCT-treated tooth with a crown alone (CRN/RCT: 571.04 +/- 154.86 N). The predominant mode of failure was an oblique fracture extending from the lingual margin to the facial

  1. Knowledge and attitude of some nigerian school teachers on the emergency management of avulsed permanent incisor.

    Science.gov (United States)

    Olatosi, O O; Iwuala, S O; Isiekwe, G I; Oredugba, F A; Adenaike, A S; Oluwo, A O

    2013-01-01

    Tooth avulsion has been known to be the most severe of all dental injuries. The immediate action taken at the accident site will determine the prognosis of the tooth. Replantation of an avulsed tooth is the treatment of choice. To assess the knowledge and attitude of primary and secondary (Basic educational) school teachers on the emergency management of avulsed permanent incisors. Twenty public and private basic educational schools were randomly selected from Lagos State. Descriptive cross-sectional study. A 23 item self administered questionnaire was distributed to teachers to determine their knowledge and attitude on the emergency management of avulsed permanent incisors. Data was analysed using SPSS (Statistical Package for Social Sciences), Version 21.0. The responses obtained were tabulated and expressed as frequency distributions and then computed in percentages. Chi-square was used to test the association between knowledge of the schools teachers regarding the emergency management of avulsed permanent incisors and their socio-demographic variables. Multivariate analysis was used to adjust for confounding variables. The level of significance was set at P ≤0.05. A total of 320 teachers answered the questionnaires. Most of the teachers were female (63.1%). Only (30.9%) had received first aid training which included emergency management of dental trauma. Forty- two percent (134) didn't know that an avulsed permanent tooth could be replanted. Twenty teachers (44.4%) would clean an avulsed tooth with toothbrush and toothpaste. A greater proportion of the respondents 130 (40.6%) would transport an avulsed tooth using a clean white handkerchief. The overall knowledge of the school teachers was poor (84%).There was a statistically significant association between the knowledge of the school teachers and the inclusion of emergency management of dental trauma in the first aid training of the teachers P=0.05. Predictors of teachers' level of knowledge of emergency

  2. Comparison of the buccolingual inclination in alveolar bone and tooth using dental CBCT

    International Nuclear Information System (INIS)

    Kim, Sung Eun; Kim, Jin Soo; Kim, Jae Duk

    2008-01-01

    It is important to determine the bucco-lingual inclination of implants on radiographs before the implant surgery. The purpose of this study was to compare the buccolingual inclination in alveolar bone and the tooth with dental cone beam CT and to prepare the standard for the buccolingual inclination of implant. Axial, panoramic, and buccolingually sectioned images of 80 implant cases with stent including straight marker using CB Mercuray TM (Hitachi, Japan) were evaluated. The comparison of the buccolingual inclination of remained alveolar bone with the tooth and the marker on buccolingually sectioned views was performed statistically. The average buccolingual inclination of remained alveolar bone and tooth was 82.8 ± 4.6 .deg. C and 85.8 ± 4.7 .deg. C (p 0.05, r=0.12) at the 2nd premolar area in upper jaw. The average buccolingual inclination of remained alveolar bone and tooth was 81.3 ± 8.3 .deg. C and 87.5 ± 6.3 .deg. C (p>0.05, r=0.85) at the lower 2nd premolar area and 94.3 ± 6.6 .deg. C and 93.3 ± 7.2 .deg. C respectively (p>0.05, r=0.91) at the 1st molar area in lower jaw. The inclinations of markers were very different from those of remained bone at the most of areas except the upper 2nd premolar area (r=0.79). We recommend dental CBCT analysis for determining the buccolingual inclination of dental implant, because of significant difference, in average, between the buccolingual inclination of remained alveolar bone and tooth.

  3. The metabolic cost of walking on an incline in the Peacock (Pavo cristatus)

    OpenAIRE

    Wilkinson, Holly; Thavarajah, Nathan; Codd, Jonathan

    2015-01-01

    Altering speed and moving on a gradient can affect an animal’s posture and gait, which in turn can change the energetic requirements of terrestrial locomotion. Here, the energetic and kinematic effects of locomoting on an incline were investigated in the Indian peacock, Pavo cristatus. The mass-specific metabolic rate of the Indian peacock was elevated on an incline, but this change was not dependent on the angle ascended and the cost of lifting remained similar between the two inclines (+5 a...

  4. Prevalence and aetiology of Molar-Incisor Hypomineralisation among children aged 8-10 years in Tirana, Albania.

    Science.gov (United States)

    Hysi, D; Kuscu, O O; Droboniku, E; Toti, C; Xhemnica, L; Caglar, E

    2016-03-01

    Molar incisor hypomineralisation (MIH) describes the clinical appearance of enamel hypomineralisation of systemic origin affecting one or more permanent first molars (PFMs) that are frequently associated with affected incisors. The aim of this study was to investigate the prevalence and aetiology of MIH in children living in Tirana, Albania. The study was conducted at the Department of Paediatric and Preventive Dentistry, Faculty of Dental Medicine, and Tirana Dental Public Health Service. A total of 1,575 school children aged 8-10 years were examined by 7 calibrated examiners (dentists) (kappa: 0.86). The Weerheijm criteria were used for the diagnosis of demarcated opacities, post-eruption breakdown, atypical restorations, and extracted PFMs due to MIH. Prevalence of MIH was found to be 14% (n=227). In the 227 children with MIH, tooth 36 was the most affected PFM, and tooth 46 the least affected. Tooth 21 was the most affected incisor and tooth 32 the least affected incisor by MIH. MIH(+) children had significanly more childhood diseases in the first 3 years of life (p=0.006). Among the children who used antibiotics, MIH(+) cases were 1.41 (1.06-1.87) times higher than in children who did not usedantibiotics, MIH(-) cases. MIH was found to be common among 8-10 year-old Tirana children.

  5. Characteristics of the Papua New Guinean dentition. I Shovel-shaped incisors and canines associated with lingual tubercles.

    Science.gov (United States)

    Doran, G A

    1977-10-01

    The prevalence of shovel-shaped and lingual tubercles in maxillary incisors and canines in four groups of people in Papua New Guinea is reported. The shovel shape was not common among the people of Highland New Guinea but its presence in Papuans was comparable with that in Mongoloid races.

  6. Orthodontic Space Closure Versus Prosthetic Replacement of Missing Upper Lateral Incisors in Patients With Bilateral Cleft Lip and Palate

    NARCIS (Netherlands)

    Oosterkamp, Barbara C. M.; Dijkstra, Pieter U.; Remmelink, Hendrik J.; van Oort, Robert P.; Sandham, John

    2010-01-01

    Objective To compare dental aesthetics and function of orthodontic space closure versus prosthetic replacement of upper lateral incisors in patients with bilateral cleft lip and palate The predominant mode of prosthetic replacement was resin-bonded bridges Patients and Methods The retrospective

  7. The Safe Zone Range for Cup Anteversion Is Narrower Than for Inclination in THA.

    Science.gov (United States)

    Murphy, William S; Yun, Ho Hyun; Hayden, Brett; Kowal, Jens H; Murphy, Stephen B

    2018-02-01

    Cup malposition is a common cause of impingement, limitation of ROM, acceleration of bearing wear, liner fracture, and instability in THA. Previous studies of the safe zone based on plain radiographs have limitations inherent to measuring angles from two-dimensional projections. The current study uses CT to measure component position in stable and unstable hips to assess the presence of a safe zone for cup position in THA. (1) Does acetabular component orientation, when measured on CT, differ in stable components and those revised for recurrent instability? (2) Do CT data support historic safe zone definitions for component orientation in THA? We identified 34 hips that had undergone revision of the acetabulum for recurrent instability that also had a CT scan of the pelvis between August 2003 and February 2017. We also identified 175 patients with stable hip replacements who also had a CT study for preoperative planning and intraoperative navigation of the contralateral side. For each CT study, one observer analyzed major factors including acetabular orientation, femoral anteversion, combined anteversion (the sum of femoral and anatomic anteversion), pelvic tilt, total offset difference, head diameter, age, sex, and body mass index. These measures were then compared among stable hips, hips with cup revision for anterior instability, and hips with cup revision for posterior instability. We used a clinically relevant measurement of operative anteversion and inclination as opposed to the historic use of radiographic anteversion and inclination. The percentage of unstable hips in the historic Lewinnek safe zone was calculated, and a new safe zone was proposed based on an area with no unstable hips. Anteriorly unstable hips compared with stable hips had higher operative anteversion of the cup (44° ± 12° versus 31° ± 11°, respectively; mean difference, 13°; 95% confidence interval [CI], 5°-21°; p = 0.003), tilt-adjusted operative anteversion of the cup (40°

  8. Spiral computed tomography in the evaluation of relations of the impacted maxillary canines and the adjacent incisor roots

    International Nuclear Information System (INIS)

    Siegel, R.; Stos, W.; Dyras, M.; Urbanik, A.; Wojciechowski, W.; Sztuk, S.

    2009-01-01

    Background: The relations of the crowns of impacted maxillary canines and the roots of adjacent incisors are difficult to evaluate on conventional radiographs due to superimposition of shadows of these structures. The aim of this study was to analyse the relations between the crowns of impacted canines and the roots of adjacent incisors with the use of computed tomography. Material/Methods: The study involved a group of 65 patients suspicious for an impacted maxillary permanent canine. All the patients underwent pantomography. In 44 individuals in the age of 13-31 years (mean age 17.1 ± 4.5) the examination revealed shadows of the impacted crowns superimposed on the roots of incisors. These patients were subjected to CT. On the basis of those CT examinations (including multiplanar and three-dimensional reconstructions) we defined the location of the impacted canines as buccal, palatal and horizontal. Likewise, the relations between the crowns of impacted canines and the roots of lateral or/and central incisors were studied. Results: From among 54 impacted maxillary canines, 41 (75.9%) were located palatally, 10 (18.5%) buccally, and 3 (5.6%) horizontally. In 14 cases (29.5%), the impacted canine remained in various kind of contact with both adjacent incisors. In addition to those aforementioned 14 cases, the impacted maxillary canine remained in contact with adjacent root of the lateral incisor in 34 cases (in total: 48 cases of contact). We found 17 cases (35.4%) of adherence without features of root resorption and 31 cases (64.4%) of resorption. Among the cases of resorption, there were 18 instances of deep resorption (58.1%) and 13 instances of light resorption (41.9%). There were also 18 cases (33.3%) of contact between the impacted canine and the root of the central incisor, including 10 instances (55.6%) of adjacency without root resorption and 8 cases (44.4%) of resorption. Conclusions: Computed tomography allows for a precise localisation of the impacted

  9. A Case Report of Compound Odontoma Associated with an Unerupted Maxillary Central Incisor

    Directory of Open Access Journals (Sweden)

    Eda Arat Maden

    2014-02-01

    Full Text Available Odontomas generally appear as small, solitary or multiple radio-opaque lesions found on routine radiographic examinations. Traditionally, odontomas are the most common type of odontogenic tumor and they are generally asymptomatic. Occasionally, odontomas may cause disturbances in the eruption of teeth, such as impaction, delay eruption or retention of primary teeth. In general, odontomas occur more often in the permanent dentition. This is a case report of a compound composite odontoma in an 8-year-old boy, which has resulted in failure of eruption of the permanent upper right central incisor while the contra-lateral tooth had erupted. [Arch Clin Exp Surg 2014; 3(1.000: 47-51

  10. Radiographic and clinical aspects of endodonty of the central incisor, in maxilla: a case report

    International Nuclear Information System (INIS)

    Panella, J.; Freitas, A. de; Freitas, C. de

    1989-01-01

    The authors in the current report introduce a study of the present features when of agenesis of dental elements on the maxilla-mandibular complex. They relate a case of right upper central incisor's hypodontia, describing its clinical and radiographic appearances. Through a large revision of literature about this field, they found out that a disappearance of this element on the human dentition is rare, associating for this: genetic, familiar, nutrient, hormonal, infections and traumatic agents. Finally, they alert for the fact that an accurate clinical examination, complemented by a exact radiographic survey, will make possible a precocious diagnosis and execution of more efficient therapeutic manipulations that reduce the problems of functional, esthetic and phonetics order. (author)

  11. Genome-wide association study (GWAS) for molar-incisor hypomineralization (MIH).

    Science.gov (United States)

    Kühnisch, Jan; Thiering, Elisabeth; Heitmüller, Daniela; Tiesler, Carla M T; Grallert, Harald; Heinrich-Weltzien, Roswitha; Hickel, Reinhard; Heinrich, Joachim

    2014-01-01

    This genome-wide association study (GWAS) investigated the relationship between molar-incisor hypomineralization (MIH) and possible genetic loci. Clinical and genetic data from the 10-year follow-up of 668 children from the Munich GINI-plus and LISA-plus birth cohort studies were analyzed. The dental examinations included the diagnosis of MIH according to the criteria of the European Academy of Paediatric Dentistry (EAPD). Children with MIH were categorized as those with a minimum of one hypomineralized first permanent molar. A GWAS was implemented following a quality-control step and an additive genetic effect was assumed. A total of 2,013,491 single-nucleotide polymorphisms (SNPs) were available for analysis. Rs13058467, which is located near the SCUBE1 gene on chromosome 22 (p MIH when using a threshold of p value MIH.

  12. Multidisciplinary management of subgingival crown-root fracture of an immature permanent maxillary central incisor

    Directory of Open Access Journals (Sweden)

    Samir Zahedpasha

    2012-01-01

    Full Text Available This case report describes the multidisciplinary management of subgingival horizontal crown-root fracture of an immature permanent maxillary central incisor in a 10-year-old boy. After removal of the fractured fragment, pulpotomy was performed within 48 h from the injury to promote apexogenesis. The tooth was orthodontically extruded until the fracture line was located above the alveolar bone level. Frenectomy, supracrestal fiberotomy, and crown lengthening were performed after adequate stabilization of the extruded tooth for 5 months. Finally, the tooth was restored with composite resin by using the acid etch technique. This report highlights that a multidisciplinary treatment approach with strict cooperation among specialists to manage a complicated crown-root fracture can save and restore a traumatized immature permanent tooth.

  13. Management of recurrent fracture of central incisor with internal resorption using light transmitting (luminex post

    Directory of Open Access Journals (Sweden)

    Hariharan V

    2010-01-01

    Full Text Available The normal root canal anatomy may be altered in various pathological processes and making it very difficult and at times impossible to achieve ideal obturation by normal methods. Internal resorption is one among them. There are several treatment protocols advised for this pathological condition. A crown-root fracture is defined as a fracture involving enamel, dentin and cementum and accounts for 5% of all traumatic injuries to the permanent dentition. In anterior teeth, these fractures are usually caused by direct trauma and often complicated in fully erupted teeth. In cases where the fracture line extends down along the long axis of the root, extraction of the tooth is indicated. The purpose of this report is to present the use of light transmitting post system to reinforce the crown root fractured maxillary central incisor due to trauma and internal resorption.

  14. Diagnosis and management of maxillary incisors affected by incisal wear: an interdisciplinary case report.

    Science.gov (United States)

    Bernardo, Jussara Karina; Maia, Elaine A Vilela; Cardoso, Antônio Carlos; de Araújo Júnior, Edson Medeiros; Monteiro Júnior, Sylvio

    2002-01-01

    In the attempt to restore anterior teeth affected by erosion and bruxism, many clinicians have been frustrated with the constant restorative failures. Frequently, these failures are attributed to the restorative materials employed, especially in cases in which composite resins are used. However, some flaws of the restorations are related to the oversight of occlusal principles. The purpose of this article is to discuss the etiology, signs, and symptoms of incisal wear, with special attention to that caused by bruxism and chemical erosion. Relatively simple management techniques (e.g., occlusal adjustment, adhesive restorations) are proposed, and the diagnosis and management of a representative clinical case is presented. In some cases of bruxism and/or dental erosion, it is possible to acquire space to recuperate the esthetics and function of maxillary incisors affected by incisal wear through a conservative treatment associated with the control of the etiologic factors.

  15. Macrodontia, shovel-shaped incisors, and multituberculism: probable Ekman-Westborg-Julin trait.

    Science.gov (United States)

    Reardon, Gayle Tieszen; Slayton, L Rebecca; Norby, Clinton; Geneser, Teresa

    2012-01-01

    Multiple macrodontia is a rare finding and is defined as a condition in which a tooth is significantly larger than normal. Macrodontia may occur as an isolated finding, part of a group of dental anomalies, or as a component of a syndrome with multiple oral and systemic manifestations. The purpose of this paper was to report a case of macrodontia affecting all permanent teeth and exhibiting shovel-shaped maxillary and mandibular incisors and multituberculate molars and premolars. Some or all of this patient's characteristics have been reported in both males and females, with a ratio of 5:2. No inheritance pattern has been established, as these traits have generally occurred spontaneously. As more individuals are identified and as molecular techniques continue to advance, it is probable that a gene or genes responsible for macrodontia and the associated traits will be identified.

  16. Structure and microstructure of coronary dentin in non-erupted human deciduous incisor teeth

    Directory of Open Access Journals (Sweden)

    Costa Luciane R.R S.

    2002-01-01

    Full Text Available The dentin structure of non-erupted human deciduous mandibular and maxillary central and lateral incisor teeth was studied employing light and scanning electron microscopy. For light microscopy, nitric-acid-demineralized and ground sections were used. The sections were stained by hematoxylin-eosin, picrosirius and azo-carmim methods, and ground specimens were prepared using a carborundum disk mounted in a handpiece. For SEM study, teeth were frozen in liquid nitrogen and fractured at longitudinal and transversal directions. Structurally, demineralization and ground methods revealed tubules with primary and secondary curvatures, canaliculi, giant tubules, interglobular dentin, predentin, and intertubular dentin. Scanning electron microscopy showed three-dimensional aspects of dentinal tubules, canaliculi, peritubular dentin, intertubular dentin, and predentin. This study contributes to knowledge about dentin morphology showing characteristics of teeth not yet submitted to mastication stress.

  17. Zirconia crowns for rehabilitation of decayed primary incisors: an esthetic alternative.

    Science.gov (United States)

    Ashima, G; Sarabjot, K Bhatia; Gauba, K; Mittal, H C

    2014-01-01

    Esthetic management of extensively decayed primary maxillary anterior teeth requiring full coronal coverage restoration is usually challenging to the pediatric dentists especially in very young children. Many esthetic options have been tried over the years each having its own advantages, disadvantages and associated technical, functional or esthetic limitations. Zirconia crowns have provided a treatment alternative to address the esthetic concerns and ease of placement of extra-coronal restorations on primary anterior teeth. The present article presents a case where grossly decayed maxillary primary incisors were restored esthetically and functionally with ready made zirconia crowns (ZIRKIZ, HASS Corp; Korea). After endodontic treatment the decayed teeth were restored with zirconia crowns. Over a 30 months period, the crowns have demonstrated good retention and esthetic results. Dealing with esthetic needs in children with extensive loss of tooth structure, using Zirconia crowns would be practical and successful. The treatment described is simple and effective and represents a promising alternative for rehabilitation of decayed primary teeth.

  18. A Retrospective Study of Association between Peg-shaped Maxillary Lateral Incisors and Dental Anomalies.

    Science.gov (United States)

    Kim, Jae-Hwan; Choi, Nam-Ki; Kim, Seon-Mi

    The purpose of this study was to investigate the prevalence of peg-shaped maxillary lateral incisors and the incidence of associated dental anomalies in children. We investigated the prevalence of peg-laterals and incidence of associated dental anomalies in 3,834 children aged 7-15 who visited the Department of Pediatric Dentistry from January 2010 to December 2015 and underwent panoramic radiographs. The prevalence of peg-laterals was 1.69% in boys, 1.75% in girls, and 1.72% overall. Among children with peg-laterals, the frequencies of associated dental anomalies were as follows: congenitally missing teeth, 31.8%; dens invaginatus, 19.7%; palatally displaced canines, 12.1%; supernumerary teeth, 7.6%; and transposition, 7.6%. As children with peg-laterals have a higher incidence of other dental anomalies, careful consideration is needed when planning diagnosis and treatment.

  19. Retreatment of failed regenerative endodontic of orthodontically treated immature permanent maxillary central incisor: a case report

    Directory of Open Access Journals (Sweden)

    Musaed Fahad Al-Tammami

    2017-02-01

    Full Text Available A revascularization procedure was shown to be the best alternative therapy for immature teeth with necrotic pulp and apical infection. A 12 year old female with a history of trauma to her upper central incisor and a sinus tract was referred for endodontic treatment. She was an active orthodontic patient and had undergone regenerative endodontic treatment for the past 2 years. Clinical examination revealed no response to sensibility, percussion, and palpation tests. The preoperative radiograph showed an open apex and apical rarefaction. The case was diagnosed as previously treated tooth with asymptomatic apical periodontitis. Regenerative endodontic retreatment was performed, and the case was followed for 3 years. Clinical, radiographic, and cone-beam computed tomography follow-up examination revealed an asymptomatic tooth, with evidence of periapical healing and root maturation.

  20. Very Large Inflammatory Odontogenic Cyst with Origin on a Single Long Time Traumatized Lower Incisor

    Science.gov (United States)

    Freitas, Filipe; Andre, Saudade; Moreira, Andre; Carames, Joao

    2015-01-01

    One of the consequences of traumatic injuries is the chance of aseptic pulp necrosis to occur which in time may became infected and give origin to periapical pathosis. Although the apical granulomas and cysts are a common condition, there appearance as an extremely large radiolucent image is a rare finding. Differential diagnosis with other radiographic-like pathologies, such as keratocystic odontogenic tumour or unicystic ameloblastoma, is mandatory. The purpose of this paper is to report a very large radicular cyst caused by a single mandibular incisor traumatized long back, in a 60-year-old male. Medical and clinical histories were obtained, radiographic and cone beam CT examinations performed and an initial incisional biopsy was done. The final decision was to perform a surgical enucleation of a lesion, 51.4 mm in length. The enucleated tissue biopsy analysis was able to render the diagnosis as an inflammatory odontogenic cyst. A 2 year follow-up showed complete bone recovery. PMID:26393219

  1. Biologic restoration of a traumatized maxillary central incisor in a toddler: a case report.

    Science.gov (United States)

    John, Sheen Ann; Anandaraj, S; George, Sageena

    2014-01-01

    Trauma to the anterior teeth is relatively common in young children and teenagers. Traumatized anterior teeth require quick functional and aesthetic repair, and poses a challenge to the dental practitioner owing to the lack of co-operation ceded and the longer time invested. Reattachment of tooth fragment should be the first choice to restoring teeth when a usable fragment is available, since it gives a psychological and aesthetic advantage over the conventional technique. With the vast improvement in adhesive technology, reattachment is definitely a predictable treatment option for very young children. This paper describes the treatment of a 2½ year old female child who sustained crown-root fracture, extending subgingivally, in primary upper central incisor.

  2. Minimally invasive restoration of a maxillary central incisor with a partial veneer.

    Science.gov (United States)

    Horvath, Sebastian; Schulz, Claus-Peter

    2012-01-01

    Minimally invasive treatment modalities allow for the preservation of sound tooth substance. However, by limiting the preparation to the extent of a defect, the transition between restoration and natural tooth may be moved to more visible areas. The materials available for the restoration of a limited defect in the anterior area are either resin composite materials or porcelain. A patient was presented who asked for the replacement of a discolored filling on the maxillary right central incisor. Tooth preparation was limited to the extent of the old filling, and a porcelain partial veneer restoration was fabricated. Despite the horizontal finish line in the middle of the clinical crown, a result could be achieved that was regarded as a success by the patient. This type of restoration proves to be a suitable alternative to direct composite restorations in the anterior area for the reconstruction of a limited defect, eg, due to a dental trauma.

  3. Corono-radicular biological restoration of maxillary central incisors by direct method.

    Science.gov (United States)

    Aggarwal, Sonia; Sahoo, Sujit Ranjan; Pandharkar, Kartik

    2014-11-01

    This case report refers to the esthetic and functional restorations of extensively damaged maxillary central incisors with dental caries in a 32-year-old woman, with the use of posts and crowns made from natural extracted teeth. Proper restoration of such teeth with the use of natural teeth fragments are known as "biological restoration." Biological restorations can be done by using the fragments of the patients own tooth and if that is not available, tooth fragment can be obtained from an extracted tooth. These biological posts and crowns present a low cost option and an alternative technique for the morphofunctional recovery of extensively damaged teeth. There are limitations with the use of natural extracted teeth (homogenous bonding) for restoration such as the difficulty of finding teeth with a similar color and shape as that of the destroyed element, or patient may refuse to accept a tooth fragment from another patient, which prevents execution of the restoration.

  4. Inclination shallowing in the Eocene Linzizong sediments from Tibet: correction, possible causes and implications for reconstructing the India-Asia collision

    NARCIS (Netherlands)

    Huang, W.; Dupont-Nivet, G.; Lippert, P.C.; Hinsbergen, D.J.J. van; Hallot, E.

    2013-01-01

    A systematic bias towards low palaeomagnetic inclination recorded in clastic sediments, that is, inclination shallowing, has been recognized and studied for decades. Identification, understanding and correction of this inclination shallowing are critical for palaeogeographic

  5. Healing process of incisor teeth of diabetic rats replanted after storage in milk.

    Science.gov (United States)

    Ricieri, Camila Benez; Sonoda, Celso Koogi; Aranega, Alessandra Marcondes; Panzarini, Sônia Regina; Poi, Wilson Roberto; Sundefeld, Maria Lúcia Marçal Mazza; Okamoto, Tetuo

    2009-06-01

    Several local factors that influence the healing process of replanted teeth have been investigated. However, it remains unclear how systemic alterations, such as diabetes mellitus, affect the prognosis of these cases. The purpose of this study was to evaluate the healing process of incisors of non-controlled diabetic rats replanted after storage in bovine long shelf-life (UHT) whole milk. Thirty-two rats were randomly assigned to receive an endovenous injection of either citrate buffer solution (group I - control; n = 16) or streptozotocin dissolved in citrate buffer solution to induce diabetes (group II; n = 16). After confirmation of the diabetic status by analysis of the glycemic levels, the maxillary right incisor of each animal was extracted and immersed in milk for 60 min. The root canals of teeth were then instrumented, and were filled with a calcium hydroxide-based dressing and replanted into their sockets. All animals received systemic antibiotic and were killed by anesthetic overdose 10 and 60 days after replantation. The specimens containing the replanted teeth were removed, fixed, decalcified, and embedded in paraffin. Semi-serial 6-microm-thick sections were obtained and stained with hematoxylin and eosin for histologic and histometric analyses. The results showed that the connective tissue adjacent to the root surface was less organized in the diabetic animals than in the control animals in both periods; the root dentin was less severely affected by root resorption in the diabetic rats; there were no significant differences between the control and diabetic groups regarding the occurrence of replacement resorption and inflammatory resorption.

  6. Social and behavioral risk factors for maxillary incisor trauma in an adolescent Arab population.

    Science.gov (United States)

    Artun, Jon; Al-Azemi, Rashed

    2009-12-01

    The majority of dental traumas are due to falls or blows during regular activity, personal interaction and play inside or outside the home, suggesting that behaviors associated with certain social conditions are risk factors. Our purpose was to explore that hypothesis. We examined a population-based sample of 1583 13-14-year-old subjects in a classroom setting. Incisor trauma was scored according to the National Institute of Dental Research index, and overjet was measured to the nearest 0.5 mm. Presence of mesial migration and/or loss of first molars and/or open caries in permanent teeth were recorded and categorized as increased caries experience. Body mass index (BMI) was calculated from standardized measurements of height and weight, as weight in kg height(-1) in m(2). Obesity was scored if BMI exceeded 30. Information on participation in physical activities, family income, and number of siblings was collected through subject and family interview. Univariate logistic regression detected reduced trauma risk among subjects of high income families (P = 0.009) and among subjects attending private schools (P = 0.026). Sports and physical activities were more prevalent in boys than in girls (P = 0.000) and associated with trauma in the sample as a whole (P = 0.001), but not separately in boys and girls. No effect was detected of obesity, number of siblings and increased caries experience. Univariate analyzes also detected increased trauma risk in boys (P = 0.000) and in subjects with increasing intervals of overjet (P = 0.000). Following use of multiple regressions with forward selection, only male gender, increasing overjet, and high family income were included in the final prediction model. Our findings suggest that behaviors associated with high family income and private school attendance reduce the risk of incisor trauma among adolescents in Kuwait, and that the gender difference in sports activities is an unlikely explanation for the gender difference in trauma.

  7. Orthodontic correction of severely rotated maxillary central incisor in a diabetic adult

    Directory of Open Access Journals (Sweden)

    Rajesh Gyawali

    2015-12-01

    Full Text Available Background: Orthodontics has recently seen an increase in the number of adult population seeking treatment. Financial dependency, increasing awareness and availability of service can be the reasons behind this rise. Though, clinical myths regarding duration, effectiveness of treatment, associated systemic conditions still exist, these should be of no concern and with adequate monitoring and procedural modifications, conventional orthodontic treatment is possible.Case description: A 58 year old Type II diabetic male presented to orthodontic clinic with unesthetic gap between upper front teeth. The history revealed extraction of painful mesiodens. On examination, the patient had Class I molar, canine and incisor relationship. 21 was rotated with 5mm of space between central incisors. Fixed orthodontic treatment was planned after physician consultation regarding his diabetic condition. Bondable buccal tubes instead of bands were used in first molars, 0.022” Roth brackets were bonded on other maxillary teeth. The wire gradually progressed from 0.014”NiTi, 0.016”NiTi to 0.018”SS. Lingual button was attached on the labial and lingual surface of 21 to apply couple. After the correction of rotation of 21, remaining space closure with esthetic contouring of 21 was done. Maintenance of adequate oral hygiene was reinforced throughout the treatment period. Fixed lingual retainer was bonded and pericision performed to retain the achieved result.Conclusion: Orthodontic treatment can be carried out in diabetic adults with good glycemic control to achieve esthetic results; however, measures for maintenance of adequate oral hygiene should be undertaken. Interdisciplinary approach involving restorative procedures can enhance the esthetics achieved.JCMS Nepal. 2015;11(3:30-34

  8. Torquing an upper central incisor with aligners--acting forces and biomechanical principles.

    Science.gov (United States)

    Hahn, Wolfram; Zapf, Antonia; Dathe, Henning; Fialka-Fricke, Julia; Fricke-Zech, Susanne; Gruber, Rudolf; Kubein-Meesenburg, Dietmar; Sadat-Khonsari, Reza

    2010-12-01

    The forces delivered by aligners during torquing have still not been investigated. The purpose of this study was to measure the forces delivered to an upper central incisor during torquing with three different materials of the same thickness, and to describe the biomechanical principles of torquing with aligners. Five identical appliances were manufactured from each of three materials, all with a thickness of 1.0 mm (Ideal Clear®, Erkodur®, and Biolon®). An upper central incisor, as part of the measuring device, was torqued in defined steps in the vestibular and palatal directions with the respective appliance in place. For statistical analysis, the resulting forces, Fx (forces acting in the palatal and facial directions) and Fz (intrusive force as a side-effect) at a displacement of ±0.15 and ±0.8 mm from the tooth at the gingival margin were calculated. The mean Fx forces for ±0.15 mm displacement ranged from -1.89 N [standard deviation (SD) 0.48] to 0.11 N (SD 0.1). The mean Fz forces were between -0.97 N (SD 0.57) and -0.07 N (SD 0.22). The highest intrusive forces were measured during palatal displacement of the measuring tooth. An influence of direction of displacement on the levels of force was observed, especially for Fz at the greater displacement of ±0.8 mm. In relation to the intended amount of root movement during torquing, aligners tend to 'lift up' and therefore no effective force couple can be established for further root control. The force delivery properties are also influenced by the material used and the shape of the tooth.

  9. Beam Shear Design According to Eurocode 2 - Limitations for the Concrete Strut Inclinations

    DEFF Research Database (Denmark)

    Hagsten, Lars German; Hestbech, Lars; Fisker, Jakob

    2011-01-01

    and are presented. These beams are all designed to fail in shear and the shear reinforcement is designed for different values of the concrete strut inclinations (cot θ varies from 1.5 to 3.4). These tests indicate a clear connection between the values of the concrete strut inclinations and crack width in the SLS......The beam shear design method adopted in Eurocode 2 is based on a lower bound plastic solution. This method is combined with limitations on the concrete strut inclination, θ. These limitations are introduced to ensure acceptable crack width in the SLS. 7 full scale beams have been tested....... In cases where larger crack widths (w > 0.4 mm) can be accepted, larger values of the concrete strut inclinations can be chosen. This will lead to less shear reinforcements. The results are also compared with analytical analysis based on energy methods. At the SLS the beams are expected to be cracked...

  10. Natural circulation of integrated-type marine reactor at inclined attitude

    International Nuclear Information System (INIS)

    Iyori, Isao; Aya, Izuo; Murata, Hiroyuki; Kobayashi, Michiyuki; Nariai, Hideki

    1987-01-01

    A steady-state single-phase natural circulation test was performed to clarify the effect of inclination by using a model of an integrated-type marine reactor. It was found that several types of flow pattern occur in the natural circulation loop corresponding to the range of inclination angle. Stable flow rates are sustained up to near 90 0 because of the occurrence of a driving force arising from those sections of the facility which were horizontal before the inclination. It was found that the temperature distribution in the steam generator at inclined attitude depends essentially only on the elevation z. The applicability of a one-dimensional analytical model was examined. It was clarified that employment of detailed U-turn flow paths, their correlation, and temperature-distribution function of core is essential for improvement. (orig.)

  11. Experimental research of inclined-micro-fin flat tube on single phase convection heat transfer

    International Nuclear Information System (INIS)

    Fan Guangming; Sun Zhongning; Wang Meng

    2011-01-01

    The experimental research of heat transfer and flow resistance characteristics of single phase water in four inclined-micro-fin flat tubes with different physical dimensions was conducted. At the same time,suitable criteria were selected to evaluate the efficiency of inclined-micro-fin flat tubes within the experimental scope and the optimal working region was determined. The results indicate that inclined-micro-fin flat tubes can greatly enhance the single-phase heat transfer in turbulent flow and the maximum heat transfer coefficient attains to 5.9 times of that in smooth tube. The quantities of heat transfer for inclined-micro-fin flat tubes are three times higher than that of smooth tube with the same of heat exchange area and pump power. (authors)

  12. Solar cell options based on different geographical locations and wall inclination

    Science.gov (United States)

    Ma, Jie

    2018-05-01

    Two major trends in the development of contemporary solar energy science and technology [1]: First, the combination of light and point, the second is the combination of solar energy and construction. A large number of houses at the top of the installation of solar water heaters and other primary solar energy utilization equipment can no longer meet the needs of the majority of users, people pay more attention to the ventilation and heating of housing and solar power supply and other integrated multi-purpose building construction. Under the condition of simplification, this model gives the options of laying suitable solar cells for houses with different geographical positions and different inclination angles according to the actual situation. Based on our model, firstly we calculate the wall radiation according to the model (WRCM) to get the light radiation of the wall of the house, and then according to the power generation model (PGM), we can calculate the output of several types of batteries in the selected range. Finally, through the economic benefits mode l (EBM), we get the economic benefits of each type of battery in different places, and then we can choose the most suitable battery type. At the end of the article, we take Datong, Shanxi Province as an example, and substitute the relevant data from online search into the model. Compared with the actual situation, we verify that the model has good applicability.

  13. Lateral dynamic flight stability of a model hoverfly in normal and inclined stroke-plane hovering

    International Nuclear Information System (INIS)

    Xu, Na; Sun, Mao

    2014-01-01

    Many insects hover with their wings beating in a horizontal plane (‘normal hovering’), while some insects, e.g., hoverflies and dragonflies, hover with inclined stroke-planes. Here, we investigate the lateral dynamic flight stability of a hovering model hoverfly. The aerodynamic derivatives are computed using the method of computational fluid dynamics, and the equations of motion are solved by the techniques of eigenvalue and eigenvector analysis. The following is shown: The flight of the insect is unstable at normal hovering (stroke-plane angle equals 0) and the instability becomes weaker as the stroke-plane angle increases; the flight becomes stable at a relatively large stroke-plane angle (larger than about 24°). As previously shown, the instability at normal hovering is due to a positive roll-moment/side-velocity derivative produced by the ‘changing-LEV-axial-velocity’ effect. When the stroke-plane angle increases, the wings bend toward the back of the body, and the ‘changing-LEV-axial-velocity’ effect decreases; in addition, another effect, called the ‘changing-relative-velocity’ effect (the ‘lateral wind’, which is due to the side motion of the insect, changes the relative velocity of its wings), becomes increasingly stronger. This causes the roll-moment/side-velocity derivative to first decrease and then become negative, resulting in the above change in stability as a function of the stroke-plane angle. (paper)

  14. Phase states of a 2D easy-plane ferromagnet with strong inclined anisotropy

    International Nuclear Information System (INIS)

    Fridman, Yu. A.; Klevets, F. N.; Gorelikov, G. A.; Meleshko, A. G.

    2012-01-01

    We investigate the spin states of a 2D film exhibiting easy-axis anisotropy and a strong single-ion inclined anisotropy whose axis forms a certain angle with the normal to the film surface. Such a system may have an angular ferromagnetic phase, a spatially inhomogeneous state, and a quadrupole phase, whose realization depends substantially on the inclined anisotropy and the orientation of the wavevector in the film plane.

  15. Relativistic and the first sectorial harmonics corrections in the critical inclination

    Science.gov (United States)

    Rahoma, W. A.; Khattab, E. H.; Abd El-Salam, F. A.

    2014-05-01

    The problem of the critical inclination is treated in the Hamiltonian framework taking into consideration post-Newtonian corrections as well as the main correction term of sectorial harmonics for an earth-like planet. The Hamiltonian is expressed in terms of Delaunay canonical variables. A canonical transformation is applied to eliminate short period terms. A modified critical inclination is obtained due to relativistic and the first sectorial harmonics corrections.

  16. Performance evaluation of a continuous flow inclined solar still desalination system

    International Nuclear Information System (INIS)

    El-Agouz, S.A.; El-Samadony, Y.A.F.; Kabeel, A.E.

    2015-01-01

    Highlights: • A mathematical model was presented to analyze the performance of inclined still. • The effect of air speed, water masses, film thickness and velocity was studied. • Productivity for the Model 3 was higher than conventional still by 57.2%. • The performance was strongly affected by water film thickness and velocity. • Model 3 gave the highest performance while Model 1 gave the lowest performance. - Abstract: In the present work, theoretical study of the performance evaluation of a continuous water flow inclined solar still desalination system is performed. Three models are studied for inclined solar still desalination system with and without water close loop. The effects of the water mass, water film thickness, water film velocity and air wind velocity on the performance of the three models are studied. The results show that the inclined solar still with a makeup water is superior in productivity (57.2% improvement) compared with a conventional basin-type solar still. Also, the application of inclined solar still with open water loop is recommended when combined with other still desalination system due to high water temperature output. The inclined solar still with a makeup (Model 3) gives the highest performance while Model 1 gives the lowest performance. Finally, the water film thickness, and velocity as well as wind velocity plays important roles in improving the still productivity and efficiency

  17. Interfacial friction factors for air-water co-current stratified flow in inclined channels

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Ki Yong; No, Hee Cheon [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)

    1997-12-31

    The interfacial shear stress is experimentally investigated for co-current air-water stratified flow in inclined rectangular channels having a length of 1854mm, width of 120 mm and height of 40mm at almost atmospheric pressure. Experiments are carried out in several inclinations from 0 deg up to 10 deg. The local film thickness and the wave height are measured at three locations, i.e., L/H = 8,23, and 40. According to the inclination angle, the experimental data are categorized into two groups; nearly horizontal data group (0 deg {<=} {theta} {<=} 0.7 deg), and inclined channel data group (0.7 deg {<=} {theta} {<=} 10 deg ). Experimental observations for nearly horizontal data group show that the flow is not fully developed due to the water level gradient and the hydraulic jump within the channel. For the inclined channel data group, a dimensionless wave height, {Delta}h/h, is empirically correlated in terms of Re{sub G} and h/H. A modified root-mean-square wave height is proposed to consider the effects of the interfacial and wave propagation velocities. It is found that an equivalent roughness has a linear relationship with the modified root-mean-square wave height and its relationship is independent of the inclination. 10 refs., 6 figs., 1 tab. (Author)

  18. The metabolic cost of walking on an incline in the Peacock (Pavo cristatus).

    Science.gov (United States)

    Wilkinson, Holly; Thavarajah, Nathan; Codd, Jonathan

    2015-01-01

    Altering speed and moving on a gradient can affect an animal's posture and gait, which in turn can change the energetic requirements of terrestrial locomotion. Here, the energetic and kinematic effects of locomoting on an incline were investigated in the Indian peacock, Pavo cristatus. The mass-specific metabolic rate of the Indian peacock was elevated on an incline, but this change was not dependent on the angle ascended and the cost of lifting remained similar between the two inclines (+5 and +7°). Interestingly, the Indian peacock had the highest efficiency when compared to any other previously studied avian biped, despite the presence of a large train. Duty factors were higher for birds moving on an incline, but there was no difference between +5 and +7°. Our results highlight the importance of investigating kinematic responses during energetic studies, as these may enable explanation of what is driving the underlying metabolic differences when moving on inclines. Further investigations are required to elucidate the underlying mechanical processes occurring during incline movement.

  19. Proposal of a novel compact P-band magnetically insulated transmission line oscillator with inclined vanes

    Science.gov (United States)

    Zhang, Xiaoping; Dang, Fangchao; Li, Yangmei; Jin, Zhenxing

    2015-06-01

    In this paper, we present a novel compact P-band magnetically insulated transmission line oscillator (MILO) with specially inclined slow-wave-structure (SWS) vanes to decrease its total dimension and weight. The dispersion characteristics of the inclined SWS are investigated in detail and made comparisons with that of the traditional straight SWS. The results show that the inclined SWS is more advantageous in operating on a steady frequency in a wide voltage range and has a better asymmetric mode segregation and a relatively large band-gap between the TM00 and TM01 modes which are in favor of avoiding the asymmetric and transverse mode competition. Besides, the transverse dimension of the proposed novel inclined SWS with the same operation frequency is decreased by about 50%, and correspondingly the device volume shrinks remarkably to its 0.35 times. In particle-in-cell simulation, the electron bunching spokes are obviously formed in the inclined SWS, and a P-band high-power microwave with a power of 5.8 GW, frequency of 645 MHz, and efficiency of 17.2% is generated by the proposed device, which indicates the feasibility of the compact design with the inclined vanes at the P-band.

  20. Interfacial friction factors for air-water co-current stratified flow in inclined channels

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Ki Yong; No, Hee Cheon [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)

    1998-12-31

    The interfacial shear stress is experimentally investigated for co-current air-water stratified flow in inclined rectangular channels having a length of 1854mm, width of 120 mm and height of 40mm at almost atmospheric pressure. Experiments are carried out in several inclinations from 0 deg up to 10 deg. The local film thickness and the wave height are measured at three locations, i.e., L/H = 8,23, and 40. According to the inclination angle, the experimental data are categorized into two groups; nearly horizontal data group (0 deg {<=} {theta} {<=} 0.7 deg), and inclined channel data group (0.7 deg {<=} {theta} {<=} 10 deg ). Experimental observations for nearly horizontal data group show that the flow is not fully developed due to the water level gradient and the hydraulic jump within the channel. For the inclined channel data group, a dimensionless wave height, {Delta}h/h, is empirically correlated in terms of Re{sub G} and h/H. A modified root-mean-square wave height is proposed to consider the effects of the interfacial and wave propagation velocities. It is found that an equivalent roughness has a linear relationship with the modified root-mean-square wave height and its relationship is independent of the inclination. 10 refs., 6 figs., 1 tab. (Author)