X2 Endo™ #31 Molar (LR7)

X2 Endo™ · #31 lower right second molar · dual hardness

Every canal curving the same way, which is harder than it sounds

What makes a second molar harder than a first? Access is further back, the crown is smaller, and the roots tend to lean together. Acadental describe the X2 Endo #31 as a two-rooted mandibular second molar with two canals in the mesial root and one in the distal, and note that both the mesiobuccal and mesiolingual canals carry moderate curvature in the distolingual direction. When every canal curves the same way, a straight-line access is not a formality – and with a crown built to resist a bur like enamel, the cavity has to be earned.

This item: 1 × X2 Endo #31, lower right second molar (LR7), radiopaque
Made by Acadental, USA · mfr code 3D_AE601X2_31

› The hardest X2 tooth – postgraduate and hands-on course material rather than a first molar attempt.
› Films that read properly – curvature in the distolingual direction is exactly what a single straight-on radiograph hides, which makes this a good angulation exercise too.
› The see-through version – Endo 3DP #31 adds a calcified ribbon-shaped distal canal, visible from outside, but does not radiograph.

Why does one curve direction matter?
Because a file pre-curved for the mesiobuccal is already right for the mesiolingual – and the operator who has not noticed will fight both. It is a small insight that changes how people work.

Do we need a glide path?
On moderate curvature in every canal, yes. Establish patency and a glide path with small hand files before any engine-driven instrument.

Where should this sit in a course?
Last. Start on #30 for a conventional first molar, then move here once access and three-canal work are solid.

Complete the system

X2 Endo™ #31 · lower right second molar LR7 · two roots, three canals · MB and ML curve distolingually · dual hardness · radiopaque · Acadental · REF ACA3D_AE601X2_31