All of the following teeth have a similar access cavity outline EXCEPT:

Single-canal anterior teeth (maxillary canine, maxillary lateral incisor) and a single-canal mandibular premolar typically have a relatively rounded-oval access outline. The maxillary first premolar, however, very commonly has two canals (roughly 85% of the time), requiring a more elongated, buccolingually oval/rectangular access outline to locate both canal orifices — making it the outlier among these options.