In the maxillary anterior region, the gingival labial margin position is an important parameter in the achievement of an ideal smile. The relationship between the periodontium and the restoration is critical if gingival health and esthetics are to be achieved. Periodontal therapy is a necessary and useful adjunct when any anterior restoration is undertaken. Anterior surgical crown lengthening m...

Research shows that practitioners tend to underestimate the amount of tooth structure that must be exposed during a crown lengthening procedure. In the anterior portion of the mouth, this can lead to biologic width problems and subsequent cosmetic issues. This paper presents a biologically based, step-by-step approach to periodontal esthetic crown lengthening. Using a series of innovative measu...

Crown or modern sarcopterygians (coelacanths, lungfishes, and tetrapods) differ substantially from stem sarcopterygians, such as Guiyu and Psarolepis, and a lack of transitional fossil taxa limits our understanding of the origin of the crown group. The Onychodontiformes, an enigmatic Devonian predatory fish group, seems to have characteristics of both stem and crown sarcopterygians but is diffi...

In order to present the reasonable crown of hot rolling mills, the bend force and shift position should be pre-computed in a reasonable manner, while maintaining a good profile. How to search the optimal crown trajectory in ratio crown range is the key problem. Crown and flatness allocation strategy is researched based on dynamic programming method which has been improved and optimized by the a...

This study describes sexual dimorphism in dental indexes derived from the permanent dentition. Three dental indices--'crown area,' 'crown module' and 'crown index'--were calculated from the buccolingual (BL) and mesiodistal (MD) measurements of 123 permanent dentitions (58 females and 65 males) belonging to young Nepalese adults (age-range 19-28 years). Sex differences in the dental indexes wer...

Crown rust, caused by the fungal pathogen, Puccinia coronata Corda var. avenae W.P. Fraser Ledingham, reduces kernel quality and grain yield in oat (Avena sativa L.). Partial resistance is considered to be a durable form of rust resistance. This study sought to evaluate the feasibility of simultaneously improving partial resistance to crown rust, grain yield, and seed weight in an oat populatio...

PURPOSE The aim of this study was to evaluate the mesiodistal primary tooth size diameter and posterior sagittal tooth-size ratio in an African American population and compare to existing African American and European American norms. METHODS A sample of 1,124 African American children, 564 males and 560 females, was used to record crown size diameters employing indirect (cast) and direct (int...

The morphologic relationship of the crown structures of the maxillary second deciduous molar (m2) and the first permanent molar (M1) was investigated with odontometric methods. Materials used were 124 male dental casts taken from Chinese living in Kaohsiung (Taiwan). The mesiodistal and buccolingual diameters, cusp sizes, and intercusp distances were measured. The mean crown diameters were larg...

Single crystals formed from hydrogen-bonding supramolecular cations of o-aminoanilinium (HOPD)­crown ethers, (HOPD)([12]crown-4), (HOPD)([15]crown-5), and (HOPD)([18]crown-6), and one-electron-reduced [PMo12O40] Keggin-type clusters were synthesized. The crystal structures and dielectric responses of the three new compounds (HOPD)4([12]crown-4)4[PMo12O40]¢4CH3CN (1), (HOPD)4([15]crown-5)4[PMo12...

Current understanding of aspen fire ecology in western North America includes the paradoxical characterization that aspen-dominated stands, although often regenerated following fire, are “fire-proof”. We tested this idea by predicting potential fire behavior across a gradient of aspen dominance in northern Utah using the Forest Vegetation Simulator and the Fire and Fuels Extension. The wind spe...