When Dale Podolsky started his medical residency in plastic and reconstructive surgery at the University of Toronto three years ago, he already had impressive credentials as a mechanical engineer. But he never thought his two disparate skill sets might combine to solve one of the great challenges in plastic surgery: repairing the cleft palates of infants by operating inside their mouths.

Affecting one in every 700 babies, a cleft palate occurs when the roof of the mouth — and often the upper lip — doesn’t fully form during fetal development, causing disfigurement and an inability to eat, speak, or breathe normally. It is the most common of all birth defects, yet even experienced surgeons struggle to repair it in infants, who have small mouths and delicate oral tissue.

Podolsky’s solution? A true-to-life model of a baby’s mouth that surgeons can practise with before they reach the operating room, something so desperately needed that orders are pouring in from all over the world. University hospitals in North America and charities that provide training in developing countries — where few children have the procedure, owing to a lack of skilled plastic surgeons — believe the model could revolutionize surgical instruction.

Christopher Forrest, head of plastic and reconstructive surgery at the Hospital for Sick Children, has spent 22 years training resident surgeons to repair cleft palates and has fixed hundreds himself. Even now, he says, the procedure makes him nervous. Since only one set of hands can operate in the space, he says, “I need to have the highest trust in the trainee. Trainee performance always deviates slightly from that of an experienced surgeon, but the tolerance for deviation is very low” — in other words, one slip can be disastrous.