The arch circumference of individual patients varies depending upon the tooth and jaw size, type of malocclusion, stage of growth and treatment, etc. Objective: The arch circumference varies during the different stages of treatment, in extraction and nonextraction cases and between different ethnic groups. Hence necessitating larger preformed archwires to be supplied. This, although helpful, leads to a lot of unnecessary units of the archwire material with concomitant environmental hazards.

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... study was, therefore, undertaken to quantify this wastage vis-a-vis different types of malocclusion, stage of treatment, etc. Materials and methods: Pre and post-treatment models of patients were taken and divided into three groups: Group A-Class I Bimax, Group B-Class I crowding and Group C-Class II division 1 cases treated with 1st premolar extractions. A flexible curve scale was used to measure the arch perimeter circumference of the models and the wires. Results: The preformed upper 016 NiTi was 26 and 15% longer in cases bonded upto 1st molar and 2nd molars respectively. Similarly lower 016 NiTi was 29 and 17% in surplus. During the finishing stages, the NiTi wires used in the upper arch was 31% for upto 1st molar and 24% for upto 2nd molar bonding/binding in excess. The lower wire in the same case was 36 and 23% respectively, in excess.