Purpose: To observe histologically the response of submerged root segments for both vital and endodontically treated teeth.
N= 3 monkeys ( Cebus apellae )
Materials and methods:
•Each monkey was radiographed, weighted and anesthetized using a tranquilizer.
•Diagonally opposed anterior teeth were treated endodontically ( Group A ) N= 17 teeth
•Isolation, pulp extirpation, cleaning and shaping, irrigation using 95% ethanol, LC of GP and sealed with Cavit.
•The opposite anterior teeth were left vital ( Group B ) N=19 teeth, and the first premolars were the controlled group
•Labial and lingual mucoperiosteal envelope flaps were reflected in the Max. and Mand. arches
•Crowns removed using low speed burr, coronal segments fractured to the labial notch, sharp projections refined.
•Suture was made to secure closure of the labial and lingual submucosal layers using 4-0 black silk suture.
•Block jaw sections of the three monkeys were obtained.
•Experimental observation was divided to 2-weeks, 5-weeks and 25 weeks after surgery.
Most highlighted results:
•Vital segments demonstrated a higher submersion success rate than GP filled segments.
•Vital submerged segments demonstrated coronal bridging.
•Successfully submerged segments ( Vital and GP filled ) showed connective tissue attachment.
•The pulpal tissues of unsuccessfully submerged vital segments demonstrated degenerative changes.
Submerged root segments without any signs and symptoms should not be removed and observed.