Posterior_Direct_Restorations Salvatore_compressed

FIG 2-16 Maxillary right second premolar. (a and b) The position of the central developmental groove is approximately centered mesiodistally and buccopalatally; its mesiodistal extension is shorter than on the first premolar. (c) The space occupied by the marginal ridges is accordingly greater. (d) The quantity of supplemental ridges and grooves is extremely variable; the anatomy ranges from only slightly to very accentuated depending on individual tooth characteristics.

FIG 2-17 (a to c) Maxillary right first and second (left) premolars.

FIG 2-18 (a and b) Maxillary second premolars.

Maxillary Molars

Compared with the maxillary premolars, the maxillary molars are relatively dissimilar to one another (Fig 2-19). The first molar is very bulky; it is often accompanied by an accessory cusp (cusp of Carabelli), which is located palatal to the mesiopalatal cusp. A distinctive oblique

ridge joins the mesiopalatal and distobuccal cusps. The buccopalatal diameter of the maxillary molars is wider than the mesiodistal diameter. On the maxillary second molars, the smallest cusp (distopalatal) may be missing.

FIG 2-19 Maxillary left first (left) and second molars.

Maxillary first molar

The maxillary first molar has four cusps (five if the cusp of Carabelli is included) (Fig 2-20). The mesiopalatal cusp is the largest. Specific features include: