Trying to differentiate a small to midsize Nanotyrannus and Dakotaraptor is pretty difficult.  It appears that Dakotaraptor teeth are not common and sellers are quick to assign Nanotyrannus teeth to them.   So what should one be looking for with the teeth   It's a Dromaeosaurid so it will have similarities to Acheroraptor but there are differences.   1)  Smooth Crown         These teeth do not have the vertical ridges found in Acheroraptor and are larger and beefier   2)  Serration Density The serrations on the mesial (outer) edge are greater than the distal ( inside ) carina  (measured midline over 5 mm) Mestai: 5-6 serration/mm Distal: 4-5 serrations/mm  These are from Adult Teeth -- juvenile teeth may be greater but there is always a difference Caution: Small Nano teeth can be found with mesial densities greater than distal but are not has fine around 2 to 3 /mm   3) Carina Shape/Location Distal: Extends to the base Mesial: Often does not reach the base and is straight.  Ends 1/3 from the base.    Nanotyrannus:  Mesial carina may have a slight sigmoidal twist not extend to the base depending on location in jaw   4) Shape of Crown/Base Teeth are recurved and compressed.   Base is elongate, narrow oval or almond shape in cross-section.  Usually has a greater height to length ratio than Acherorapter or Nanotyrannus.   Should be 1.6 to 1.9   (Crown Height/Length Base)  Nanotyrannus typically has a rectangular base in cross-section    5) Size  Crowns  7/8" (2-2.3 cm) in the holotype.     6) Denticle Shape Rounded tip Nano: Chisel Shape tip   Caution 1 Some of the characteristics overlap between Dakotaraptor and Nanotyrannus so you need to take a look at all of them before you make a call 2 The sample size of Dakotaraptor teeth is very small so we really do not have a good sense of what all tooth positions look like especially with juvenile one.       Mesial carina does not extends to the base (red line) Should be straight no twist       Two examples          Foot claws Only foot claws have been found see photo. The large claw is Digit II killing claw and the other claw is typical of the other three claws in the foot. NO hand claws have been found so we do not know what they look like.