Orthodontic Simulation of Forces and Moments Using Space Generation Mechanics with a Lingual Bracket System

• Author / Creator

  Robertson, Lindsay

• Objectives: Evaluation of the three dimensional (3D) forces and moments exerted by lingual orthodontic brackets in a simulated dental arch with crowded teeth. Statistical and mechanical analysis of the forces and moments between two different treatment mechanics (NiTi coil springs and archwire stops) and two different archwire systems (straight and mushroom) were used to understand which systems may produce the most physiologic forces and moments.

  Methods: Data was collected using an Orthodontic Simulator (OSIM); an in-vitro model of the human mouth to measure 3D forces and moments on each tooth in the dental arch. Lingual braces were positioned on anatomically designed metal teeth on the OSIM. The metal teeth simulations were attached to load cells which measured the 3D forces and moments experienced by all of the teeth in the dental arch simultaneously. Teeth in the anterior dental arch were moved from a crowded position to the desired neutral uncrowded position to simulate space generation for a crowded dentition. Four experimental groups were examined: 1. NiTi coil springs with straight archwires, 2. NiTi coil springs with mushroom archwires, 3. Archwire stops with straight archwires, 4. Archwire stops with mushroom archwires. Statistical analysis was utilized to determine differences in treatment mechanics between the groups.

  Results: Three overall observations were noticed during our analysis: 1. Mushroom archwires had similar mean force and moment values despite which treatment type was used, 2. Coils treatment mechanics had similar mean force and moment values despite which archwire type was used, 3. Both archwire types had greater mean force and moment values when using stops compared to coils.

  Conclusions: There were differences in the mean forces and moments of interest (Fx, Fy, Mx, My, Mz) experienced by the teeth of interest (maxillary first premolars and maxillary lateral incisors) between the two different treatments (coils and stops) and the two different archwires (straight archwires and mushroom archwires) at the maximum crowded position. Many of the forces and moments measured were above the threshold for clinically significant tooth movement.

• Subjects / Keywords

  • Lingual
  • Orthodontics

• Graduation date

  Fall 2019

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/r3-2czc-ts60

• License

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