Invitro investigation of tooth discoloration induced by CEM cement in three media and different time intervals

</strong> Beauty is considered as one of the most important aspects of dentistry both by the dentist and patient. The use of some dental materials can result in a change of tooth color hence dissatisfaction of the patient. The aim of present study was an invitro investigation of tooth discoloration induced by CEM cement in three media and different time intervals.</span></span>
 
</strong>T the crown of forty extracted maxillary central incisors were sectioned  from the coronal part of the root and one millimeter below CEJ in their buccal surface. Access cavity was prepared and pulp chamber content was emptied. Then, a cavity was mede in the middle third of the interior wall of pulp chamber buccal surface using fissure bur. The teeth were assigned to three experimental groups with blood, 5.25% sodium hypochlorite, normal saline media  and one control group. The experimental group teeth were respectively smeared with fresh human blood, 5.25% sodium hypochlorite and normal saline. Then, their residues were aspirated so that a clear vision could be obtained to the walls stained with the solutions mentioned above. Next, the cavities created in the buccal surface of the pulp chamber were filled with CEM cement in all of the experimental groups and the control group teeth were left empty. After the complete set of CEM cement, the access cavity and the root ending part of the teeth were sealed using resin-modified glass inomers (RMGI). The teeth colors were investigated and recorded before CEM cement placement (T0), immediately after placement (T1) as well as after one day (T2), seven days (T3) and thirty days (T4). The data were finally analyzed using SPSS 17 software and Kruskal-Wallis and repeated measure tests.</span>
 
Results</strong>: the highest and lowest tooth discoloration were respectively pertained to the blood and sodium hypochlorite groups. The highest discoloration were found occurred in experimental and control groups respectively one and seven days after cement placement. The lowest color change was evidenced respectively one day and 30 days after cement placement in the blood group and the other groups (table 1).
 
</strong> blood and sodium hypochlorite contact with CEM cement causes a tooth discoloration and this cement has to be utilized on crown after establishing perfect hemostasis and dryness.</span>
 
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