The mean expansion obtained between cusp tips and between cervical-palatal points was , respectively : for inter-canine width , @ mm and @ mm with the Haas appliance and @ mm and @ mm with the Hyrax appliance ; as for first deciduous molars or first deciduous premolars , the values obtained were @ mm and @ mm in the Haas group , and @ mm and @ mm in the Hyrax group ; with regard to first molars , values were @ mm and @ mm in the Haas group , and @ mm and @ mm in the Hyrax group .