A Randomized Clinical Trial to Compare the Clinical Application of an Innovated Transpalatal Arch (TPA) Fabricated From 3D Reconstructed Model With Conventionally Constructed TPA.

INTRODUCTION

Transpalatal Arch (TPA) has been invented by Dr. Robert Ara Goshgarian, a renowned orthodontist more than 7 decades ago. Throughout the years, various modifications of the design were made for different purposes and to increase its efficacy in achieving the optimum level of anchorage. In 1947, fabrication of Nance Palatal Ach (NPA) pioneered the adjustment of TPA by incorporation of an acrylic button that connects the palatal wire at the highest part of palatal vault. Recent innovations mostly involved adhesions of TPA to mini implants or temporary anchorage devices (TAD) and proven to be time and cost effective to be used in orthodontics. The usage of TPA for space maintenance demonstrated to be more advantagous in term of soft tissue compatibilty and increase in vertical control compared to Nance appliance. The combination of TPA and extraction of deciduos maxillary canines in the late mix dentition has shown to be an acceptable interceptive treatment to prevent maxillary canines palatal impaction. Despite numerous changes and alterations, the versatility of usage has made TPA remained as a useful adjunct in clinical orthodontics until today. However the fabrication of TPA required meticulous clinical steps which started with insertion of elastomeric separators on mesial and distal interproximal surfaces of maxillary permanent first molar teeth. One week later, separators were removed and series of molar bands selection or 'try in' session were carried out to get the correct size that fits the molar teeth. The drawbacks of this action is that, the 'used' molar bands if not properly decontaminated with an enzymatic cleaning and properly sterilized using autoclave, it may constitute a cross-infection hazard. An impression with molar bands in situ were taken and sent to the dental lab for fabrication of TPA followed by re-insertion of separators between the molar teeth. This means that each patient has to bear the discomfort caused by elastomeric separators for at least two weeks time or more. Orthodontists have to spent time for molar bands selection and dental technicians have more workload from pouring of impression until finishing of TPA.

RATIONALE

Patients do not have to undergo twice elastomeric separators placement as reported that among 4 orthodontic treatment procedures carried out,(upper alginate impression, separator placement, band placement and adjustment of arch wire), placement of separator causes a significant bacteraemia. Clinicians could cut down the number of appointments and time could be utilized to see more other cases. Currently there are 7 dental technicians in Paediatric and Orthodontic Department to cater for 10 Orthodontists, 6 Senior Postgraduates and 5 Junior Postgraduates, 1 technician was assigned for Optech management at Balai Ungku Aziz and starting from 2018, all technician will be involved in dental chair maintenance for the whole UM. Heavy workload and other commitments resulted in lack of time to finish all orthodontic cases.

AIM