Gesichtsästhetik Teil 1: Die Bedeutung der Symmetrieebene des Gesichts

When humans observe a face, the eyes, mouth and nose regions are the preferred targets of the centre of gaze, with the outlines of eye position recordings approximating a triangle with vertices located in the centre of the eyes and mouth [31]. We studied the significance of cutaneous asymmetries inside and outside the Yarbus triangle on the basis of the assessment of digitally-manipulated images by 201 independent judges. We show that certain facial variations (such as naevi) are more attractive when asymmetrical than symmetrical (p<?0,001). They appear more attractive when located laterally rather than medially, particularly so when located outside the Yarbus triangle as compared to inside it (p<?0,001). The significance of facial symmetry increases significantly when approaching the Yarbus triangle or the midline, respectively.     

Craniectomy and noggin application in an infant model.

INTRODUCTION: Noggin is an antagonist of bone morphogenetic proteins (BMP)-2, -4 and -7. Little data are available regarding its clinical utility. Two hypotheses were put forward: firstly, that spontaneous regeneration of calvarial defects with noggin protein would result in diminished bone volume when compared with calvarial defects not so treated. Secondly, that centrifugal cranial expansion would remain undisturbed whether noggin was applied or not. MATERIAL AND METHODS: A unilateral defect of the frontal and parietal bones (2x4cm) was generated by excising the right coronal suture in 2-month-old minipigs (n=10) and in group 1 (n=5) no further intervention was undertaken. In the second group (n=5), a collagen type I tissue fleece and noggin protein (1.05mg/ml) were applied. After 4 months the coronal suture regions of frontal sides were examined in each animal by computed tomography and non-decalcified histology. RESULTS: Bony gaps of equivalent size remained in animals of both groups. The differences in bone volumes of the experimental sides of group 1 were not statistically significantly different (p=0.117) when compared with those of group 2. A significant difference in the bone volumes of the experimental versus control (unoperated) sides was found in both group 1 (p=0.043) and group 2 (p=0.043). Internal skull diameters increased by 16.4% in both groups but the physiological centrifugal cranial expansion remained undisturbed. Bone densities of the experimental and control sides of groups 1 and 2 were not statistically significantly different (both p>0.05). CONCLUSIONS: The first hypothesis was contradicted: the quantity and quality of spontaneous bone regenerates was not altered by application of noggin protein. The second hypothesis was confirmed: no disruption of subsequent cranial development was seen. It may be that a single application of noggin protein in this study was insufficient. However, it may well be suggested that the continuous supplementation of noggin, for example by adenoviral noggin gene transfer may significantly reduce the quantity of spontaneous bone regeneration in a similar experiment.     

Ensuring success in alveolar bone grafting: a three-dimensional approach

Alveolar bone grafting is an integral part of correcting dental arch interruption in those with cleft lip and palate. Often included within a combination of treatment modalities, alveolar grafting must be conducted in a technically effective manner and at the appropriate stage of development in order to maximize outcome and avoid morbidity. Although much regarding this procedure remains unclear, continued research and experience has provided several key insights. Bone grafting appears optimal between maxillary growth completion and maxillary canine eruption (usually between 8 and 10 years of age). Coordination of efforts and planning between surgeon and orthodontist is imperative. Correction of the alveolar defect helps not only restores dental arch continuity, but also supports the nasal base, stabilizes the maxilla, and restores volume to the lip. Appreciation of the 3-dimensional nature of the defect helps to reliably correct the defect in an anatomically correct fashion. Optimization of soft tissue, bony, and, periodontal conditions adjacent to the cleft help maximize the likelihood of success. Staging of the procedure is often necessary to maximize outcome and avoid unnecessary procedures. Here, we review several variables of alveolar bone grating based on current literature as well as our own experience.     

Survey of state funds available for rehabilitation of patients with cleft lip/palate

An effort was made to determine the amount of funds budgeted in each of the 50 U.S. states for total rehabilitation of patients with cleft lip and/or cleft palate. Questionnaires were sent following a pilot letter to the directors of each state Department of Health. Total funds per patient ranged from $17,442 for Delaware to a low of $426 for Wisconsin. Dental funds per patient ranged from $4,214 dollars for Wyoming to a low of $192 for New York.     

Reducing bacterial counts in dental unit waterlines: distilled water vs. antimicrobial agents

BACKGROUND: This study evaluated five chemical disinfectants to compare their abilities to improve dental unit waterline quality and assess their effects, if any, on the biofilm layer. METHODS: Sixty new dental units, with a closed-circuit water system, were used to compare microbial levels in DUWLs treated with five antimicrobials: Listerine, Bio 2000, Rembrandt, Dentosept, and sodium fluoride to a control group of sterile distilled water alone over a six-week period. For all units, the waterlines were filled with solution, left overnight, and then flushed for 30 seconds with sterile distilled water the following morning prior to patient treatment. Waterlines were examined for biofilm buildup using scanning electron microscopy and colony-forming-unit counts. RESULTS: The sodium fluoride and the four chemical antimicrobials reduced the microbial count to 200 cfu/ml or less. Only samples taken from dental units receiving the control treatment (distilled water with no added antimicrobial) failed to meet ADA's stated goal. Examination of the SEMs revealed an apparent decrease in the biofilm mass but not elimination, despite repeated treatment with the four antimicrobial materials. CONCLUSIONS: Even in a closed-circuit water system, distilled water alone cannot reduce microbial contamination of dental treatment water from dental unit waterlines to the 200 cfu/ml ADA stated goal. However, water treated with Listerine mouthrinse, Rembrandt mouthrinse, Bio 2000, 0.5 percent sodium fluoride and Dentosept, did meet the microbial reduction goal. The biofilm apparently was reduced in volume, but not entirely eliminated. CLINICAL SIGNIFICANCE: The ADA goal of a maximum of 200 cfu/ml was achieved using any of five chemical antimicrobials and distilled water in a closed-water system. Despite the successful reduction in microbial contamination of the dental treatment water, the biofilm was not completely eliminated. Biofilm elimination and prevention would be needed through some other means.     

Growth of acellular extrinsic fiber cementum (AEFC) and density of inserting fibers in human premolars of adolescents

The present study describes for the first time the changes of both AEFC thickness and the numerical density of collagen fibers inserting into AEFC at specified levels and sites of human premolars at different stages of development. The investigation was based on 45 premolars (25 maxillary, 20 mandibular; 25 first and 20 second), extracted from adolescents and young adults. All teeth were free of disease and presented with roots developed from 30-100% of their final length. They were prefixed in Karnovsky's fixative, decalcified in EDTA and subdivided into about 14 slices each, cut from mesial and distal root surfaces, vertical to and along the root axis. The slices were postfixed in OsO4, embedded in Epon and cut for light-microscopic study. AEFC thickness (4086 measurements) and the density of the collagenous fiber fringe (454 counts) inserting in AEFC were measured at 1, 3, 5 and 7 mm apical to the cementoenamel junction. The data obtained showed: AEFC thickness increased with age and varied between 0 and 57.5 microns. Between 9 and 17 years, cervical AEFC thickness increased in maxillary first premolars from an average of 5 to 30 microns, and in mandibular second premolars from 6 to 20 microns, i.e., AEFC grew at approximately the same rate as later in life. Depending on the differences in tooth development, AEFC on maxillary first premolars became thicker than that on mandibular second premolars. Due to the corono-apically decreasing gradient of AEFC development, its increase in mid-root regions lagged behind that in cervical regions of all teeth in people younger than about 14 yr.(ABSTRACT TRUNCATED AT 250 WORDS)