A 43 year old female is involved in an motor vehicle collision. She complains of facial and dental pain. Exam reveals a broken lateral incisor. A pink spot is noted on the surface of the tooth. What is the diagnosis? 

A. Ellis Class I Dental Fracture

B. Ellis Class II Dental Fracture

C. Ellis Class III Dental Fracture

D. Dental Subluxation

Answer: C - Ellis Class III Dental Fracture

Anatomy:

• Outer Layer is the Enamel
• Middle Layer is the Dentin
• Inner Layer is the Pulp 

Dental Fracture Ellis Classification:

• Ellis I - Fracture of Enamel (typically painless) - dental follow up +/- file sharp edge to make smooth with emery board. 
• Ellis II - Fracture of Enamel and Dentin(yellowish, very sensitive) - Dental follow up and cover exposed dentin with CaOH paste. 
• Ellis III - Fracture of Enamel, Dentin and Pulp (Reddish/ Bleeding) - Dental follow up within 24h and cover exposed pulp with cement. consider penicillin or clindamycin for pulpitis. 

Refer Here for more info on dental presentations in the Emergency Department.