Biomedical subjects

Stanley Braun

Publications and source records attributed to Stanley Braun.

6 recordsLinked to original sources

PubMed2004

Extraoral appliances: A twenty-first century update.

With the locations of the centers of resistance of the dentomaxillary complex having recently been defined, and with the newly acquired knowledge of the critical interplay between part-time extraoral and full-time intraoral force systems, the basic designs of all types of extraoral appliances are discussed in depth. Armed with this information, the clinician can improve the efficiency of all extraoral appliances to obtain better dentomaxillary-complex growth control and negate or enhance appliance-induced intraoral force systems.

Biomechanical Phenomena↗

PubMed2004

Pilot study evaluating the effects of a cervical headgear on the C-axis: the growth axis of the dentomaxillary complex.

The C-axis, a growth vector for the dentomaxillary complex, is a means of quantifying complex maxillary growth in the sagittal plane through 3 key cephalometric measurements. This pilot study examined the effect of a cervical headgear, worn 8 to 10 hours per day, on the growth axis. The mean velocity of C-axis length increase in normally growing boys in the age range studied is 1.14 mm per year. In normally growing girls, the C-axis length increase is nonlinear, varying from a mean of 1.67 mm per year at age 9 and to 0.78 mm per year at 13.5 years of age. The cervical headgear reduced the C-axis length increases by 73.7% in boys and 61.1% in girls. The growth axis vector angle theta; was not clinically affected in either sex, but the palatal plane angle alpha became more acute in both sexes, rather than becoming more obtuse as it does in normally growing adolescents. Additional research should be undertaken to determine the effects on the C-axis by other cervical headgears having different lines of action relative to the center of resistance of the dentomaxillary complex, as well as occipital-pull and straight distal-pull headgear.

Adolescent↗

PubMed2004

The G-Axis: a growth vector for the mandible.

On the basis of the G-point, defined as the center of the largest circle that is tangent to the internal inferior, anterior, and lingual surfaces of the mandibular symphysis in the sagittal view, a growth axis and its direction are described for each gender from age six to 19.25 years. Incremental growth along the G-Axis, defined by Sella-G-point, is described by regression formulas with correlation coefficients of 0.673 for female subjects and 0.749 for male subjects. The vector (direction) of the growth axis, defined by the angle alpha ((G-Axis)-(S-N)) does not materially alter in the age range studied. At age six in female subjects the angle alpha is 67.16 degrees +/- 3.03 degrees and at age 19.25 it is 66.87 degrees +/- 3.03 degrees, whereas in male subjects it is 66.12 degrees +/- 4.00 degrees and 67.93 degrees +/- 4.00 degrees, respectively. These changes and gender differences are not clinically significant. The data is based on 444 serial lateral cephalograms of 24 female subjects and 24 male subjects. The G-Axis incremental growth change and its vector offer an improved means of quantifying complex mandibular growth in the sagittal plane by using cephalometric measurements relative to and correlated with other craniofacial structures.

Adolescent↗

PubMed2004

The effect of Frankel II and modified twin block appliances on the 'C'-axis: the growth vector of the dentomaxillary complex.

The recently determined 'C'-axis, the growth vector of the dentomaxillary complex, permits an evaluation of any meaningful growth changes thereto by the Frankel II and modified Twin Block functional appliances. Retardation of the velocity of change (mm/year) in length of the 'C'-axis did not occur. The angular relationship of the 'C'-axis to Sella-Nasion (theta) and to the palatal plane (alpha) were not altered in a clinically significant way. Favorable changes observed in the correction of Class II malocclusions are likely because of dentoalveolar alterations buttressed by favorable mandibular growth.

Adolescent↗

PubMed2002

Condylar displacement related to mandibular symphyseal distraction.

This study was undertaken to determine the true nature of condylar displacements associated with mandibular symphyseal distraction osteogenesis. Earlier investigators have assumed that each mandibular half rotated about a point near the center of each condyle as viewed on a submental radiograph. In a 12-patient sample, 10 with tooth-borne symphyseal distraction and 2 with bone-borne symphyseal distraction, it was found that each condyle was laterally displaced in direct relationship to the amount of symphyseal distraction. The rigidity of the distraction appliances and their attachments and the inability of the soft tissues and muscular attachments to cause the mandible to undergo compound bending require this to be the case. Temporomandibular joints appear to be able to accommodate the lateral displacements because symptoms were not introduced, or, if present before therapy, distraction did not exacerbate them.

Adaptation, Physiological↗

PubMed2002

The Gable bend revisited.

Gable bends are frequently incorporated into a variety of loop configurations to provide appropriate moment-to-force (M/F) ratios in the controlled closure of space between individual teeth or groups of teeth. Appropriate magnitudes and occlusogingival locations of the Gable bends are shown to be vital to maintain the neutral position of the closing loop. Otherwise, the clinician has no meaningful reference point from which to judge the spring's activation to obtain the force aspect in the M/F ratio. A simple means of preserving the neutral position is shown, with the vertical loop as an example that can be applied to many common loop configurations.

Humans↗