Dr Andrew Chang and Dr Diane Tay discuss the more common teeth development defects of peg laterals (small/narrow upper 2nd front teeth), dens in dente and dens evaginatus. Common hallmarks of each of the conditions are described, and what to do when seeing teeth like these at the initial examinations. Dens in dente and dens evaginatus can both benefit from early identification and the implications of this and management options for each are discussed.