Ambreen Afzal | PubMed Health

PubMed2006

Leveling curve of Spee and its effect on mandibular arch length.

OBJECTIVE: To determine the additional space required for leveling of curve of Spee in the mandibular arch by continuous arch wire mechanics. STUDY DESIGN: Quasi-experimental interventional. SETTING: Orthodontics Department, Karachi Medical and Dental College from September 2002 to September 2004. SUBJECTS AND METHODS: Depth of curve of Spee and arch length were measured on 40 pre-treatment and posttreatment plaster models with the help of sharpened Boley gauge. RESULT: The study showed that clinical practice of allowing 1 mm of arch circumference for leveling each millimeter of curve of Spee overestimates the amount of arch space needed to flatten the curve of Spee (p < 0.001). CONCLUSION: The result suggested that the belief that 1 mm of arch circumference was necessary to level each millimeter of curve of spee present was an overestimation.

Adolescent↗

PubMed2005

Relation between centric slide and Angle's classification.

OBJECTIVE: To compare the difference in sagittal cephalometric analysis in centric occlusion (CO) and in centric relation (CR), among Angle's classes i.e. class I, class II, and class III. DESIGN: Comparative, cross-sectional study. PLACE AND DURATION OF STUDY: Orthodontic Outpatient Department, Karachi Medical and Dental College, Karachi, from July 2003 to December 2004. PATIENTS AND METHODS: Eighty pre-treatment orthodontic patients were divided into 3 groups according to Angle's classification. The first lateral cephalogram was taken in CO. Then leaf gauges were placed in between incisors for deprogramming. The second cephalogram was taken with leaf gauges in place to obtain centric relation. Both the radiographs were traced. Angle ANB was measured for sagittal analysis. ANB angle compares the position of mandible with the maxilla relating it with the cranial base. Angles from both cephalograms were compared with each other. RESULTS: Significant difference (p<0.0001) was found in values of ANB in CO (2.93 degrees -/+3.7) and CR (4.88 degrees -/+3.4) cephalograms. Significant CO-CR discrepancy was found (p<0.05) in Angle's class III patients (3.05 degrees -/+0.55) in comparison to Angle's class I (1.96 degrees -/+0.94) and class II (1.65 degrees -/+0.65). CONCLUSION: CO-CR discrepancy can occur regardless of Angle's classification. Special emphasis should be given to Angle's class III patients for the centric slide.

Adolescent↗