Changes in clinical crown height as a result of transverse expansion of the maxilla in adults

Although selection forests have clear advantages over age-group forests in view of their total growth performance, their net product and their stability, not to mention the sustainability of their beneficial effect, the proportion of this type of forest is insignificantly small in Germany and also in mixed forest in the mountains. It is therefore all the more surprising that scarcely any discernable efforts have been made to increase the proportion of selection forests. For a conversion, an alternative model for the treatment of the stands is adopted, whereby it is no longer the encouragement of the growth to maturity of individual trees in the stand which is aimed for, but rather the transformation of the whole stand to a selection forest using available stand elements and elements created by an early initiation of regeneration. Based on his experience in the forestry district of Kirchzarten in the Black Forest, Germany, the author describes the procedure for a successful conversion. This is to be started as soon as possible, that is to say when the crown height of the trees is about 18 metres and with corresponding usable dimensions, using small group shelter-wood cuts, a so-called initial femel cut. To get the conversion started it is advisable to remove whole groups of predominantly badly situated and overgrown trees. The stand will be additionally structured later through further interventions at short intervals. In the process, here and there really well situated trees will actually be left to stand solitar y, in other places w hol e self-cont aine d groups will b e created and else where valuabl e mixed s tand elements will be selected for permanent preservation, this in order to create a situation in which there are about 35 overstorey trees per hectare. On the basis of his own cost calculations, the author comes to the conclusion that the conversion is, from a financial point of view, superior compared with the age-group forest in that it brings higher proceeds more quickly and more often.

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STUDY ON HYDRAULIC CHARACTERISTICS OF ARTIFICAL REEFS WITH HIGH CROWN HEIGHT

Journal of Japan Society of Civil Engineers Ser B2 (Coastal Engineering) ◽

10.2208/kaigan.76.2_i_757 ◽

2020 ◽

Vol 76 (2) ◽

pp. I_757-I_762

Author(s):

Takahiro IWASA ◽

Ryuji NIKAIDO ◽

Fumiyasu HIRAMA ◽

Masaya TADOKORO ◽

Naoki IIJIMA ◽

...

Keyword(s):

Hydraulic Characteristics ◽

Crown Height

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Technical note: Estimating original crown height in worn mandibular canines using aspects of dentin morphology

American Journal of Physical Anthropology ◽

10.1002/ajpa.24385 ◽

2021 ◽

Author(s):

Gina McFarlane ◽

Bruce Floyd ◽

Caitlin Smith ◽

Patrick Mahoney

Keyword(s):

Technical Note ◽

Crown Height

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Changes of Periodontal Tissues Because of Orthodontic Treatment: A Retrospective Study

Journal of Advanced Oral Research ◽

10.1177/23202068211003416 ◽

2021 ◽

pp. 232020682110034

Author(s):

Hamad Alzoman ◽

Khalid Alamoud ◽

Waad K. Alomran ◽

Abdullazez Almudhi ◽

Naif A. Bindayel

Keyword(s):

Retrospective Study ◽

Orthodontic Treatment ◽

Tooth Movement ◽

Positive Impact ◽

Demographic Data ◽

Gingival Recession ◽

Confounding Factors ◽

Crown Height ◽

Periodontal Tissues ◽

Before And After

Aim: To evaluate the periodontal status before and after orthodontic treatment and to analyze the confounding factors associated with it. Materials and Methods: The present retrospective study analyzed pre- and posttreatment records of a total of 60 patients. Intraoral digital photographs before and after the orthodontic treatment were used to measure the following three periodontal variables: (a) width of the keratinized gingiva, (b) gingival recession, and (c) the status of interdental papilla. The ImageJ 46 software imaging program was used to perform the required measurements. The clinical data were then analyzed in an association with the participants’ demographic data, the type of orthodontic tooth movement, and other confounding factors. The data obtained were manually entered into the statistical package and analyzed using a significance level set at P < .05. Descriptive statistics, paired t-tests, and Pearson’s correlation analysis were used to identify differences among the studied variables. Results: Among the 60 patients, the majority (66.7%) were females. Most cases of the treated malocclusion were Class II, and most patients underwent intrusion and retrusion movements. The width of keratinized gingiva increased for most sites of upper teeth. In contrast, the lower teeth showed a mix of improvement and compromised width of keratinized gingiva. As a measure of gingival recession, the difference of clinical crown height revealed the tendency toward a reduced clinical crown height for most sites. Upper left lateral incisors and canines showed significant values with regard to keratinized gingival width measurements and tooth movements such as extrusion and intrusion movements. Likewise, with regard to the clinical crown height, upper right central incisors showed significant differences when correlated with the interincisal angle, lower incisors to the mandibular plane, and upper incisors to the NA line. The upper lateral incisors also showed significant correlations to certain cephalometric measurements. Conclusions: The orthodontic treatment was found to exert a significantly positive impact on the surrounding periodontium, particularly in the upper canine areas. Likewise, various types of tooth movement were found to positively affect the periodontium.

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Dental functional traits of mammals resolve productivity in terrestrial ecosystems past and present

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2012.0211 ◽

2012 ◽

Vol 279 (1739) ◽

pp. 2793-2799 ◽

Cited By ~ 34

Author(s):

Liping Liu ◽

Kai Puolamäki ◽

Jussi T. Eronen ◽

Majid M. Ataabadi ◽

Elina Hernesniemi ◽

...

Keyword(s):

Net Primary Productivity ◽

Terrestrial Ecosystems ◽

Functional Trait ◽

Geological Time ◽

Crown Height ◽

Short Term ◽

Functional Interpretation ◽

Terrestrial Mammals ◽

Terrestrial Biomes ◽

The Relationship

We have recently shown that rainfall, one of the main climatic determinants of terrestrial net primary productivity (NPP), can be robustly estimated from mean molar tooth crown height (hypsodonty) of mammalian herbivores. Here, we show that another functional trait of herbivore molar surfaces, longitudinal loph count, can be similarly used to extract reasonable estimates of rainfall but also of temperature, the other main climatic determinant of terrestrial NPP. Together, molar height and the number of longitudinal lophs explain 73 per cent of the global variation in terrestrial NPP today and resolve the main terrestrial biomes in bivariate space. We explain the functional interpretation of the relationships between dental function and climate variables in terms of long- and short-term demands. We also show how the spatially and temporally dense fossil record of terrestrial mammals can be used to investigate the relationship between biodiversity and productivity under changing climates in geological time. The placement of the fossil chronofaunas in biome space suggests that they most probably represent multiple palaeobiomes, at least some of which do not correspond directly to any biomes of today's world.

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