Three-Dimensional Perioral Assessment Following Subnasal Lip Lift.

BACKGROUND: The subnasal lip lift is a surgical technique that elevates the "lip line" (interface between vertical maxillary incisor height and upper lip) to achieve a more youthful aesthetic. OBJECTIVES: The authors sought to offer the first ever definition, to their knowledge, of 3-dimensional (3D) changes to the upper lip due to subnasal lip lift. METHODS: A lip lift procedure was performed (on cadaveric samples) in a sequential manner from 2.5- to 5.0-mm intervals (n = 13). 3D photographs were taken with the VECTRA H1 system (Canfield Scientific, Fairfield, NJ), and 3D analysis was performed including vermillion height and width, philtral height, sagittal lip projection, vermillion surface area, and incisor show. A subset of samples (n = 9) underwent a modification of the technique by undermining the upper lip subcutaneous tissue off the underlying muscular fascia. RESULTS: Vermillion surface area (baseline range, 1.45-5.52 cm2) increased by an average of 20.5% and 43.1% with 2.5-mm and 5.0-mm lip lift, respectively. Anterior projection of the vermillion increased in all cases by an average of 2.13 and 4.07 mm at 2.5 and 5.0 mm, respectively. Philtral height decreased in all cases by an average of 3.37 and 7.23 mm at 2.5 and 5.0 mm, whereas incisal show increased on average of 1.9 and 4.09 mm, respectively. CONCLUSIONS: This study is the first to our knowledge to define the 3D morphometric changes to the upper lip following subnasal lip lift. Quantifying these changes aids the surgeon in preoperative planning and guiding patient expectations.

Efficacy of a novel post-foaming dental gel on gingival inflammation: A randomized controlled clinical trial.

BACKGROUND: A pilot randomized controlled clinical trial was performed to evaluate the efficacy of a post-foaming dental gel containing cetylpridinium chloride (CPC), hydrogen peroxide (H2 O2 ), sodium bicarbonate, and antioxidants on periodontal/oral health. METHODS: Individuals with gingivitis or mild-moderate periodontitis (n=36) were included and randomly assigned to Group 1 and 2 with foaming gel loaded on a mouthpiece with a light source and controlled warming heat built-in unit or on a toothbrush, respectively, in addition to regular twice-daily brushing. Group 3 served as control with twice daily brushing and further assigned split-mouth to Group 3a-un-flossed and Group 3b-flossed. Gingival index (GI) and bleeding on probing (BOP) were evaluated in addition to plaque index (PI), pocket depth, and clinical attachment level at days 14, 28, 42 (treatment), and 60 (maintenance). Subgingival plaque microbial profiles and gingival crevicular fluid (GCF) cytokine levels were determined by DNA-DNA hybridization and multiplexing assays, respectively. Exploratory analyses included esthetic outcomes: changes in tooth color and levels of volatile sulfur compounds in breath. Statistical analyses were conducted using ANOVA with a post hoc analysis of Fisher's LSD. RESULTS: Use of post-foaming gel in both test groups resulted in significant changes in GI and BOP at Day 42 compared to control and un-flossed control (P<0.05). Device-enhanced foaming gel significantly reduced the PI in Group 1 at Day 42 compared to control and un-flossed control (P=0.02; P=0.007, respectively). GCF IL-6 and TNF-α levels were significantly reduced in Group 2 compared to control (PIL-6 =0.01, PTNF-α =0.02). Post-foaming gel resulted in greater reductions in periodontopathogens, whereas health-associated species remained stable. Despite cessation of adjunct treatments, Group 1 and 2 continued having reduced levels of GI, BOP, and PI at Day 60 (P<0.05). CONCLUSIONS: The novel post-foaming dental gel improves oral health by reducing gingival inflammation at the local site in addition to better esthetic outcomes.

Smile design and treatment planning with the help of a comprehensive esthetic evaluation form.

Even if a clinician possesses basic knowledge in esthetic dentistry and clinical skills, many cases presenting in modern dental practices simply cannot be restored to both the clinician's and the patient's expectations without incorporating the perspectives and assistance of several dental disciplines. Besides listening carefully to chief complaints, clinicians must also be able to evaluate the patient's physical, biologic, and esthetic needs. This article demonstrates the use of a smile evaluation form designed at New York University that assists in developing esthetic treatment plans that might incorporate any and all dental specialties in a simple and organized fashion.

Rhenium diboride's monocrystal elastic constants, 308 to 5 K.

The five independent moduli required to construct the complete monocrystal elastic modulus tensor of the hexagonal-symmetry superhard compound ReB(2) were measured from 308 to 5 K using resonant ultrasound spectroscopy on a special-texture polycrystal. This is possible because, confirmed by X-ray diffraction, the specimen measured was composed of grains with hexagonal axes parallel so that its polycrystal elastic response is identical to a monocrystal and because hexagonal-symmetry solids are elastically isotropic in the plane perpendicular to the hexagonal axis. Along the hexagonal (c) axis, C(33) (0) = 1021 GPa, nearly equal to C(11) of diamond, and consistent with the superhard properties. However, in the (softer) isotropic plane, C(11) (0) = 671 GPa, much lower than diamond. The changes of C(ij) with temperature are very small and smooth. The Debye temperature was computed to be 738 K, and using a high-temperature approximation, the Grüneisen parameter is γ = 1.7.

Preparation and properties of metallic, superhard rhenium diboride crystals.

Single crystals of ReB(2) have been prepared from an aluminum flux under inert gas flow. The crystals are typically 1-3 mm in diameter and 500 microm thick, growing along the [002] direction with a distinct hexagonal morphology. Vickers microhardness and nanoindentation testing indicate that the (002) plane possesses the highest hardness with measured values of 40.5 and 36.4 GPa, respectively. The elastic anisotropy was examined and the indentation moduli of the basal plane and an (hk0) plane of unknown indices are 675 and 510 GPa, respectively. Four-probe electrical resistivity measurements demonstrate that ReB(2) is the hardest material known to exhibit metallic behavior. Thermogravimetric analysis indicates that the crystals are stable in air up to 1000 degrees C due to the formation of a protective boron oxide coating.

Synthesis of ultra-incompressible superhard rhenium diboride at ambient pressure.

The quest to create superhard materials rarely strays from the use of high-pressure synthetic methods, which typically require gigapascals of applied pressure. We report that rhenium diboride (ReB2), synthesized in bulk quantities via arc-melting under ambient pressure, rivals materials produced with high-pressure methods. Microindentation measurements on ReB2 indicated an average hardness of 48 gigapascals under an applied load of 0.49 newton, and scratch marks left on a diamond surface confirmed its superhard nature. Its incompressibility along the c axis was equal in magnitude to the linear incompressibility of diamond. In situ high-pressure x-ray diffraction measurements yielded a bulk modulus of 360 gigapascals, and radial diffraction indicated that ReB2 is able to support a remarkably high differential stress. This combination of properties suggests that this material may find applications in cutting when the formation of carbides prevents the use of traditional materials such as diamond.