The hyperdivergent facial profile presents the orthodontist, oral surgeon, and restorative dentist with problems that might not be solvable with any one or all of our specialties. This article will review the literature on the possible predisposing and precipitating factors that might contribute to hyperdivergent facial profiles. We will attempt to correlate facial morphology as it might relate to disk displacement (DD) and degenerative joint disease (DJD). Human and animal studies will be reviewed that support these observations. Our hypothesis is that this hyperdivergent facial profile is often associated with bilateral DD and/or DJD. The effect of DD/DJD in animal and human studies and the effect of cartilage degeneration on hard and soft tissues will be reviewed. The presence of catabolic biological markers of joint degeneration (interleukin-1β, interleukin-6, matrix metalloproteinases, tumor necrosis factor-α, C-reactive protein, synovial fluid proteins) and anabolic markers (tissue inhibitors of metalloproteinases, interleukin-4, interleukin-10, interleukin-13) will be discussed. Epidemiologic studies suggest that in patients presenting with temporomandibular joint pain, there is a strong correlation between the disorder and severe mandibular retrognathia in adult women (odds ratio, 6.3). Human cephalometric studies will demonstrate that bilateral DD/DJD is highly correlated with the hyperdivergent facial profile. Follow-up orthognathic surgery studies suggest that correction might be unstable. This review will present a compelling case that the hyperdivergent facial profile is strongly correlated with bilateral DD and/or DJD. Clinicians should be aware of these findings and convey this information to patients presenting for dental treatments. The hyperdivergent facial profile presents the orthodontist, oral surgeon, and restorative dentist with problems that might not be solvable with any one or all of our specialties. This article will review the literature on the possible predisposing and precipitating factors that might contribute to hyperdivergent facial profiles. We will attempt to correlate facial morphology as it might relate to disk displacement (DD) and degenerative joint disease (DJD). Human and animal studies will be reviewed that support these observations. Our hypothesis is that this hyperdivergent facial profile is often associated with bilateral DD and/or DJD. The effect of DD/DJD in animal and human studies and the effect of cartilage degeneration on hard and soft tissues will be reviewed. The presence of catabolic biological markers of joint degeneration (interleukin-1β, interleukin-6, matrix metalloproteinases, tumor necrosis factor-α, C-reactive protein, synovial fluid proteins) and anabolic markers (tissue inhibitors of metalloproteinases, interleukin-4, interleukin-10, interleukin-13) will be discussed. Epidemiologic studies suggest that in patients presenting with temporomandibular joint pain, there is a strong correlation between the disorder and severe mandibular retrognathia in adult women (odds ratio, 6.3). Human cephalometric studies will demonstrate that bilateral DD/DJD is highly correlated with the hyperdivergent facial profile. Follow-up orthognathic surgery studies suggest that correction might be unstable. This review will present a compelling case that the hyperdivergent facial profile is strongly correlated with bilateral DD and/or DJD. Clinicians should be aware of these findings and convey this information to patients presenting for dental treatments.

For reusing code, macro variables are an indispensable part of the SAS ® system. You can create multi-use programs in which titling, subsetting, and even analysis variables can be controlled by changing the values of macro variables. To create a few macro variables, the %LET statement works extremely well. But if you want to automate the production of macro variables, DATA steps with the CALL SYMPUT statement or PROC SQL provide a better method. If a large number of macro variables need to be created from data set variables, however, even these solutions many require a great deal of typing. Furthermore, if the number of macro variables created for each data set variable and observation is extremely large, the memory demands on the system can be huge. The SAS system however, provides an elegant way to overcome these problems with the CALL SET routine. The macro version of this routine, %SYSCALL SET provides a simple way to convert data set variables into the equivalent macro variables with few lines of code. Furthermore, the routine allows you to convert and process one observation of data set variables at a time, thus saving on system memory usage. The %SYSCALL SET routine is the ideal solution for changing data set variables into macro variables.

Internal derangement has been suggested to be a cause of temporomandibular disorders. This study compared magnetic resonance imaging findings in 82 asymptomatic volunteers and 263 symptomatic patients. Disk displacement was observed in 33% of the asymptomatic volunteers and 84% of the symptomatic patients. The prevalence of trauma, headache, and other joint problems was more common in symptomatic patients. A history of general anesthesia and orthodontic treatment was not increased in the symptomatic population compared with asymptomatic volunteers. This study suggests that disk displacement is more common in symptomatic subjects.

Objective. The purpose of this study was to compare structural variations of the temporomandibular joint anatomy between symptomatic patients with temporomandibular joint dysfunction and asymptomatic controls.Study design, There were 74 symptomatic patients with temporomandibular joint dysfunction, 29 asymptomatic volunteers with normal joints, and 6 asymptomatic volunteers with disk displacement with reduction included in this study. Ail subjects had bilateral high resolution magnetic resonance imaging scans performed in the sagittal (closed and opened) and coronal (closed) positions. All subjects had right and left full profile laminagraphs, one in the centric occlusal position, and one with the incisors edge to edge.Results, Student-Newman-Keuls tests demonstrated no significant angular or linear differences for depth of the articular fossa, angle of the articular eminence, horizontal and vertical overlap of the incisor teeth, and linear condylar translation.Conclusion. This study concludes that there are no significant differences in angular and linear measurements in the articular fossa of asymptomatic volunteers and symptomatic subjects with temporomandibular joint dysfunction.

In the field of biostatistics, the reliability of a measurement technique plays a key role in its ability to yield data from which useful inferences can be derived. For example, in the area of bioequivalence testing, a low level Of reliability can serve to preclude the ability to identify truly equivalent agents without resorting to studies employing very large sample sizes. The quantification of reliability is a valuable first step in understanding the characteristics of a measurement method. This report includes a general discussion of some. basic techniques for assessing reliability, and presents SAS macros which can be used to invoke these techniques to produce user-friendly tables.

The reproducibility of electromyographic parameters descriptive of deliberate unilateral chewing (activity, timing, curve symmetry) was investigated in normal asymptomatic volunteers. The best time for the initiation of muscle activity was also examined, with the future aim of staging TMJ internal derangements. The results suggest that activity is the most reliable variable, indicating that it may be helpful in describing muscle incoordination. When time was used in conjunction with another variable, overall reproducibility decreased.

Twelve patients (mean age 24 years) presenting with facial asymmetry, thought to represent unilateral mandibular condylar hyperplasia, were included in this study. Two distinct patient groups were noted: (1) with apparent condylar hyperplasia and (2) with unilateral internal derangements. Six patients were found to have normal TMJs bilaterally and six had unilateral internal derangement occurring on the short side. Angular and linear measurements were compared using Student's t test for discrete variables between the two groups and ANOVA for continuous variables; however, they were unable to demonstrate any set of circumstances that would suggest differences between the two groups. The only clear distinction was the presence of degenerative joint disease on the short side. This suggests that standard radiographs would be helpful if other imaging studies were not performed.

Pathologic alteration of the articular disk, including moderate calcification within the meniscus proper, has been reported to occur in many cases of TMJ dysfunction with chronic anterior meniscal displacement. The purpose of this investigation was to measure, by means of direct sagittal computed tomographic scanning technology, the density (x-ray attenuation) of the meniscus. Fifty-two joints, shown to have meniscus displacement with or without reduction (MD/MDR), and 24 symptomatic joints with normal tomograms were evaluated with the use of a GE 8800 CT scanner. Mean attenuation values were extrapolated with the use of a symmetrical (1 to 9 pixels) region-of-interest (ROI) cursor. Density gradients of the masseter muscle, lateral pterygoid fat pad, and lateral pterygoid muscle were also obtained. The results of this study showed that the mean meniscal density values were 116.7 ± 4.2 Hounsfield units (HU) for MD subjects, 111.3 ± 4.6 HU for MDR subjects, and 82.4 ± 2.9 HU for subjects with symptoms. The MD and MDR density group means were significantly different (p < 0.001) from the normal group means. A relative comparison of the meniscus density with that of the lateral pterygoid muscle, its fat pad, and the masseter muscle showed a consistent mean difference when the paired t test was used. Meniscal displacement was found to be associated with an increase in density gradient, which suggests histologic alteration.

AbstractAtom–metal surface overlap integrals are of utmost importance in surface energy calculations. Direct numerical evaluation of these triple integrals can be very time‐consuming. However, we have developed an exact algebraic expression, where formulas for the coefficients are given for both the general case and the special case where the parallel wave vector is zero. Some numerical examples of the overlap for H on Al are given.

A classical model coupling a charged adspecies to a laser-induced surface plasmon is presented. Such coupling can enhance the rate and specify the direction of surface migration. For the particular case of an atomic oxygen ion of charge −1 adsorbed on aluminum which is exposed to CO2 laser radiation of intensity 1 W/cm2, the velocity of migration (61.3 μm/s) is five orders of magnitude greater than the usual thermal velocities observed at room temperature.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTTheory of laser-induced surface chemistry with applications to microelectronics and heterogeneous catalysisJui Teng Lin, William C. Murphy, and Thomas F. GeorgeCite this: Ind. Eng. Chem. Prod. Res. Dev. 1984, 23, 3, 334–344Publication Date (Print):September 1, 1984Publication History Published online1 May 2002Published inissue 1 September 1984https://doi.org/10.1021/i300015a003Request reuse permissionsArticle Views82Altmetric-Citations11LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (3 MB) Get e-Alerts

Electronic charge transfer from bulk to surface states in metals induced by laser radiation is examined. Due to the position of the Fermi energy, it is necessary to also include phonon excitations. Cross sections for this second-order process are presented. Comparison with the surface excitation in semiconductors is made. It is seen that for metals the required laser frequencies are larger and the cross sections substantially less than for semiconductors.

A semiconductor modeled by a finite one-dimensional chain is shown to have either a continuous or discrete number of surface states. The exact number is determined by the choice of phase factors. Laser-induced charge transfer of electrons from the bulk to these surface states is also shown to be a maximum at the band edge.

Laser-induced periodic pattern formation has been observed on a variety of substances. In particular, low-power lasers have been used to deposit a pattern on a metal surface. For a relatively smooth surface grating, this pattern can be explained in terms of a perturbative solution of Maxwell’s equations. However, as the surface grating is enhanced by this initial deposition, the perturbative solution breaks down. An alternate non-perturbative solution of Maxwell’s equations for such rough surfaces is considered here.