Biomedical subjects

R C Sjursen

Publications and source records attributed to R C Sjursen.

3 recordsLinked to original sources

PubMed1999

Assessment, documentation, and treatment of a developing facial asymmetry following early childhood injury.

Prepubertal trauma is often implicated as the cause of asymmetric growth of the mandible. A series of photographs taken before and after early childhood injury to the orofacial complex illustrates the development of a three-dimensional dentofacial deformity in a patient. The diagnosis and combined surgical orthodontic treatment plan to correct the facial asymmetry and malocclusion are discussed.

Adult↗

PubMed1997

On the management of extraction sites.

Extraction sites may be needed to achieve specific orthodontic goals of positioning the dentition within the craniofacial complex. The fundamental reality that determines the final position of the dentition, however, is the control exercised by the clinician in closure of the extraction sites. A specific treatment objective may require the posterior teeth to remain in a constant position anteroposteriorly as well as vertically, while the anterior teeth occupy the entire extraction site. Another treatment objective may require the reverse, or any number of purposeful alternatives of extraction site closure. An appliance system developed over time, which provides this control, is described. The system takes advantage of aspects of continuous arch therapy that provides constant, positive orientation of the anterior and posterior groups of teeth to each other in three-dimensional space across an extraction site, combined with aspects of the segmented arch technique that permit definable and predictable force systems to be applied to these teeth. Consequently, the clinician has the ability to forecast treatment outcomes with confidence.

Bicuspid↗

PubMed1997

Variable modulus orthodontics advanced through an auxiliary archwire attachment.

Reducing the load deflection rates of orthodontic springs is important, for it provides relative constancy of the moment-to-force ratio applied to the teeth with concomitant, forecastable dental movement. Increasing patient comfort and reducing the number of office visits while lowering potential tissue damage are additional features of lower load deflection rate springs. A simple auxiliary attachment, which can be crimped into position on an archwire or onto segments of an archwire, is described. This attachment permits the clinician to incorporate a relatively high rate stiff wire to enhance the anchorage of the reactive teeth in one area of the dental arch, while allowing the use of lesser stiffness (lower load deflection rate spring) to engage teeth targeted for movement. The auxiliary allows the clinician various stiffness through the use of wire of one modulus (stainless steel, for example) in one area of the arch, and wire of a differing modulus (NiTi, for example) in another area of the same arch. The advantages and disadvantages of choosing wires of differing moduli are reviewed. Alternative methods of transforming the spring rate through changes in wire cross-section or length are also reviewed. Practical clinical applications of the auxiliary attachment are shown.

Dental Alloys↗