Digital versus Manual Assessment of Arch Dimension Changes Following Four First Premolar Extraction in Bimaxillary Protrusion

Author

Mayank Gupta, Girish Chaudhary, Ajit Kumar Jaiswal, Jasmeet Kaur Ryait, Navpreet singh, Pooja Pandita

Abstract

 Background: Bimaxillary protrusion is commonly managed with extraction of four first premolars to facilitate retraction and retroclination of the anterior teeth. Changes in arch dimensions following extraction treatment are clinically relevant to treatment stability and smile esthetics. 

Methods: A retrospective analysis was performed on pre- and post-treatment diagnostic records of 29 patients with bimaxillary protrusion treated by extraction of four first premolars. Plaster models were scanned and STL files were analyzed digitally using Maestro software. The same models were assessed manually using a divider, scale, brass wire and scale. Maxillary and mandibular inter-canine width, inter-molar width and arch length were evaluated. Descriptive statistics and significance testing were performed with a significance threshold of p<0.05.

Results: Digital measurements showed increases in maxillary and mandibular inter-canine width of 1.460 mm and 1.402 mm, respectively, while inter-molar width decreased by 2.850 mm in the maxilla and 2.170 mm in the mandible. Maxillary and mandibular arch length decreased by 14.738 mm and 11.961 mm, respectively. Manual measurements showed the same overall pattern. The study reported no significant differences between corresponding digital and manual measurements.

Conclusion: Following four first premolar extraction treatment, inter-canine width increased, inter-molar width decreased and arch length decreased in both arches. Digital and manual linear measurements were considered comparably reliable.

Keywords

Bimaxillary protrusion , STL files, Arch widths, Digital, Manual

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References

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