Dros y ddau ddegawd diwethaf, cafwyd gostyngiad cyson mewn pydredd dannedd. Erbyn hyn, mae mwy o oedolion yn cadw eu dannedd a chafwyd gostyngiad cyson yn nifer y bobl sydd â dannedd gosod.
Over the last two decades there has been a steady decrease in tooth decay; more adults are keeping their teeth and there has been a steady fall in the number of people wearing dentures.