HomeOral Surgery In intra uterine life the mandible start to develop but clavicle (collar bone) start before it In intra uterine life the mandible start to develop but clavicle (collar bone) start before it. A. True B. False. Facebook Twitter Share:In intra uterine life the mandible start to develop but clavicle (collar bone) start before it Facebook Twitter WhatsApp Pinterest LinkedIn Reddit Tumblr Telegram Email