Study of Extraoral Force Delivery Systems Using Holographic Techniques

Extraoral traction is still one of the most reliable methods used during active orthodontic period especially in growing patients [1]. It is a practical and cost-effective method for attaining extra anchorage in a variety of treatment situations and it can be used either with orthodontic or orthopaedic purposes [2-3]. It is imperative for the clinician to consider the quality of the force systems, taking into account the degradation of its components, due to loss of elastic memory and material fatigue. Thus it is utterly important to understand the characteristics and mechanical behaviour of the extra oral device elements. This investigation intended to compare extraoral force delivery systems through the study of the mechanical behaviour of the plastic strap component. For this study two methods were chosen, a non-experimental technique, Finite Element Analysis (FEA), and an experimental technique ESPI. Two different manufacturers of extraoral traction systems were selected based on their market price, one of them being significantly more expensive than the other. The assessment of this data may validate the choice criteria between these two market options.