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Introduction: Regeneration of the missing papilla adjacent to single implants in the esthetic zone has always been challenging, despite advances in vertical hard and soft tissue regeneration. Orthodontic tooth extrusion has been shown to effectively gain alveolar bone and gingival tissue. This retrospective study evaluated the effectiveness of orthodontic tooth extrusion on regenerating missing papilla between existing maxillary anterior single implant and its adjacent tooth. Methods: Patients who underwent orthodontic tooth extrusion to regenerate missing papilla adjacent to a single implant in the esthetic zone were included in this study. The gingival phenotype, orthodontic extrusion movement, proximal bone level, dento‐implant papilla level, facial gingival level, mucogingival junction level, and keratinized tissue width, of the extruded tooth were recorded at pre‐orthodontic extrusion (T0), post‐orthodontic extrusion and retention (T1), and latest follow‐up (T2). Results: A total of 17 maxillary single tooth had orthodontic tooth extrusion to regenerate missing papilla adjacent to 14 maxillary anterior single implants in 14 patients. After a mean follow‐up time of 48.4 months, implant success rate was 100% (14/14), with none of the orthodontically extruded teeth being extracted. After a mean extrusion and retention period of 14.3 months, a mean orthodontic extrusion movement of 4.62 ± 0.78 mm was noted with a mean proximal bone level gain of 3.54 ± 0.61 mm (77.0% efficacy), dento‐implant papilla level gain of 3.98 ± 0.81 mm (86.8% efficacy), and facial gingival tissue gain of 4.27 mm ± 0.55 mm (93.4% efficacy). A mean keratinized tissue width gain of 4.17 ± 0.49 mm with minimal mean mucogingival junction level change of 0.10 ± 0.30 mm were observed. The efficacy of orthodontic eruption movement on dento‐implant papilla gain was less in the thin (80.5%) phenotype group when compared with that in the thick (91.5%) phenotype group. Conclusions: Within the confines of this study, orthodontic extrusion is an effective, noninvasive method in regenerating mid‐term stable proximal bone and papilla adjacent to maxillary anterior single implants. Clinical Significance: This retrospective study presents a mid‐term result on orthodontic extrusion as a mean to regenerate dento‐implant papilla defect. The extended retention period following orthodontic extrusion showed stable and efficacious proximal bone and papilla gain. [ABSTRACT FROM AUTHOR]

Experiments were conducted to quantify the temperature and pressure effects on the solubility of titanium in coesite. Powdered amorphous silica, titania (anatase), zirconia, and water were added to silver capsules and run in the coesite stability field (at 32, 35, and 40 kbar) from 700 to 1050 °C using a piston-cylinder apparatus. Crystallization of coesite, rutile, and zircon from silica-, titania-, and zircon-saturated aqueous fluids was confirmed by Raman spectroscopy. Cathodoluminescence images and electron microprobe measurements showed that coesite crystals are relatively homogenous. The Ti concentrations of coesite crystals are significantly higher than concentrations predicted using the Ti-in-quartz calibration (Wark and Watson in Contrib Mineral Petrol 152:743-754, 2006 (See CR51). 10.1007/s00410-006-0132-1; Thomas et al. in Contrib Mineral Petrol 160:743-759, 2010 (See CR48). 10.1007/s00410-010-0505-3). Titanium K-edge X-ray absorption near edge structure (XANES) measurements demonstrate that Ti.sup.4+ substitutes for Si.sup.4+ on fourfold tetrahedral sites in coesite at all conditions studied. A model was calibrated to describe the effects of pressure and temperature on the solubility of titanium in coesite by using a least-squares method to fit Ti concentrations in coesite to the simple expression: RTlnXTiO2coesite=-55.068+0.00195xT(K)-1.234xP(kbar)+RTlnaTiO2rutile, where R is the gas constant 8.3145 x 10.sup.-3 kJ/K, P is pressure in kbar, T is temperature in kelvin, [Formula omitted] is the mole fraction of TiO.sub.2 in coesite, and [Formula omitted] is the activity of TiO.sub.2 in the system referenced to rutile. Ti-in-coesite solubility can be used as a thermobarometer for natural samples when used in combination with another indicator of temperature or pressure, such as another thermobarometer in a cogenetic mineral (e.g. rutile) or other phase equilibria (e.g. graphite = diamond). Applications of the Ti-in-coesite thermobarometer to samples from the western Alps and Papua New Guinea are presented., Author(s): Zach R. Osborne [sup.1] , Jay B. Thomas [sup.1] , William O. Nachlas [sup.1] , Suzanne L. Baldwin [sup.1] , Megan E. Holycross [sup.2] , Frank S. Spear [sup.3] [...]

The details of interdisciplinary esthetic approach, which has become a respectable concept among all disciplines in dentistry, are presented. Systematic method for evaluating dentofacial esthetics in a logical and interdisciplinary manner is provided.

We examine the factors controlling accuracy and precision of monazite microprobe ages, using a JEOL 733 Superprobe equipped with 4 PET crystals, and both 1-atm gas flow Ar X-ray detectors and sealed Xe X-ray detectors. Multiple PET crystals allow for simultaneous determination of Pb concentration on up to 3 detectors, and the effects of different detector gases on spectral form can be addressed. Numerous factors in the X-ray production, detection, and counting sequence affect spectral form, including: choice of accelerating voltage, changes in d-spacing of the diffraction crystal, use of X-ray collimation slits, and type of detector gas. The energy difference between ArK[alpha] X-rays and XeL[alpha] X-rays results in, for 1-atm Ar detectors, escape peaks of second-order LREE L line X-rays that cannot be filtered using differential mode PHA. The second-order LREE energies are passed to the counter and produce, for a 140 mm Rowland circle, several problematic interferences in the Pb region of a monazite wavelength-dispersive (WD) spectrum. WD monazite spectra produced with Xe detectors are free from second-order LREE interferences in the Pb region; escape peaks of the second-order LREE are filterable with differential mode PHA if Xe detectors are employed. Silicon, Ca, Y, Ce, P, Th, U, and Pb (2 spectrometers) are measured as part of the monazite microprobe dating protocol; [+ or -] 2[sigma] variations in elements fixed for ZAF corrections do not affect the age outside of analytical uncertainty. ThM[alpha], UM[beta], and PbM[alpha] are the analyzed lines of the age components. Corrections for interference of ThM[[zeta].sub.1, 2] and YL[[gamma].sub.2,3] on PbM[alpha] are significant, but can be done precisely, and reduce the precision of theM[alpha] analysis by a trivially small amount. ThM[gamma], M3-N4, and M5-P3 interferences on UM[beta] can be corrected, as well, but ThM5 and M4 absorption edges in high-Th samples make estimation of UM[beta] background problematic. Background fits for UM[beta] peaks show that linear vs. exponential fits for UM[beta] do not, in general, produce statistically significant differences in microprobe ages. However, linear vs. exponential background fits for PbM[alpha] peaks do produce significantly different ages, most likely because of (1) low Pb concentrations relative to U; (2) ThM[zeta] interference on backgrounds between ThM[[zeta].sub.1] and PbM[beta]; and (3) SK[alpha] and K[beta] interference in S-bearing monazite. For 6-min analyses (3 min peak, 3 min background) at 25 keV and 200 nA, 1[sigma] Pb precisions are approximately 3-4% at 1700 ppm and 9.5% at 750 ppm; at 15 keV, precision decreases by roughly 25% of the 25 keV value. These precisions are constant for fixed current, analysis time, and concentration, but the statistical precision of distinct populations of monazite grains (domains) is a function of the total number of analyses within the domain. Instrumental errors (current measurement, dead time, pulse shift, d-spacing change) add 1-10% to random errors, but errors caused by pulse shift and d-spacing changes can be accounted for and corrected. Decreasing accelerating voltage from 25 to 15 keV decreases ZAF correction factors by as much as 50% relative, but replicate age analyses of Trebilcock monazite at 15 and 25 keV are statistically indistinguishable. Grain orientation, miscalculated background intensity, uncorrected interferences, and surface effects also introduce systematic errors. Accurate background interpolation and interference correction reduces systematic error to approximately 5-20% in addition to random (counting) error. Microprobe ages (~420 Ma) and[sup.208][Pb.sup.232]Th SIMS ages (~430 Ma) of monazite from Vermont are in agreement to within ~ 10 m.y. The discrepancy between U-Th-total Pb microprobe ages and [sup.208][Pb/.sup.232] Th ages is removed when the high background measurement for PbM[alpha] is shifted to the short-wavelength side of PbM[beta] removing a possible ThM[[zeta].sub.1] interference.

Four distinct generations (11 monazite growth have been identified in samples from the Chesham Pond Nappe, and three (monazite compositional domains 2, 3, and 4) have been correlated with both temperature and mineral assemblage. Domain 1 cores were interpreted previously to be detrital relies or vestiges of an earlier Acadian metamorphism. The four monazite domains have been dated by in situ isotope and chemical methods: the following are chemical ages of each domain (weighted average [+ or -] 2 standard errors of the mean): 400 [+ or -] 10 Ma (domain 1): 381 [+ or -] 8 Ma (domain 2); 372 [+ or -] 6 Ma (domain 3): 352 [+ or -] 14 Ma (domain 4). Heating and cooling rates derived from combining monazite ages, monazite thermometry, and [sup.40][Ar/.sup.39] Ar closure temperatures are approximately 10-15 [degrees]C/m.y. for heating from 470 to 740 [degrees]C. approximately 8 [degrees]C/m.y. for cooling from 740 to 375 [degrees]C, and approximately 1-2 [degrees]C/m.y for cooling from 375 to 150 [degrees]C. Temperature-time paths calculated with monazite ages and monazite thermometry indicate that (1) plutonism at ca. 400 Ma was the likely heat source for the formation of monazite domain 1 and (2) monazite domains 2-4 were produced during a regional low-pressure, high-temperature metamorphism active between 380-350 Ma. The regional metamorphism is ascribed to lithospheric mantle delamination, followed by asthenospheric mantle upwelling, which heated a wide area of the Merrimack basin (southwestern New Hampshire, central Massachusetts, central Connecticut) to temperatures in excess of 725 [degrees]C. Monazite ages in the Chesham Pond Nappe and adjacent structural units to the west constrain the commencement of nappe overthrusting to roughly 355 Ma.

Mineral compositions and reaction textures found in migmatitic gneisses from near Gilsum, New Hampshire, constrain both peak metamorphic pressure (P) and temperature (T) conditions and the PT path. Large K-feldspar porphyroblasts indicate isobaric heating of the samples at P < 4 kb (Spear et al. 1999), and relict cordierite + garnet assemblages record the occurrence of biotite vapor-absent melting; garnet-biotite thermometry yields peak temperatures of 740[degrees]C at 3.5 kbar. During melt crystallization, low-Ti biotite + sillimanite replaced cordierite, and production of muscovite indicates P > 4 kb on the cooling path. Four generations of monazite have been identified, three of which have been linked to specific whole-rock reactions. Monazite (4) (the last generation) was produced with xenotime [+ or -] apatite during melt crystallization and consumption of garnet and cordierite. Monazite (3) grew in a xenotime-absent mineral assemblage as garnet + muscovite reacted to form sillimanite + biotite. Monazite (2) grew in a xenotime-bearing [+ or -] garnet + biotite + chlorite assemblage, as xenotime and chlorite were consumed during garnet production. Monazite (1) has not been linked to a specific reaction; it may be detrital, record an earlier metamorphic event, or represent disequilibrium overgrowths of xenotime. YAG-monazite, YAG-xenotime, and monazite-xenotime thermometry for monazite generations (2)-(4) yield temperatures consistent with major-phase thermometers.