The migration of 111Indium‐labelled polymorphonuclear leucocytes into the oral cavity in the rhesus monkey

The rout of migration of ploymorphonuclear leucocytes (PMNL) from blood to the oral cavity was examined in rhesus monkeys. PMNL were isolated from the peripheral bolld of eleven rhesus monkeysby dextran sedimentation, radiolabelled with 111Indium and administered intravenously. Sequential samples of crevicular fluid washing (CFfW), mixed and parotid saliva and mucosal washing were taken after injection of the labelled PMNL and harvested on glass fibre discs. Highest numbers of labelled PMNL weren detrected in CFW. Cell‐associated radioactivity was detedfcted in CFW within 20 min of injection of labelled PMNL and reached a maximal level 1 hour after injection. PMNL were found in CFW from mondeys with clinically normal gingiva but the number of labelled PMNL in CFW increasedm with increasing gingival index. Significant numbers of PMNL migrated into mixed saliva within 30 min, and low numbers of PMNL were detedcted in mucosal washings and in parotid saliva after 30 Min. The results indicate that the migration time of the PMNL from blood to the oral cavity is less than 30 min, irespective of the gingival index, that the gingival crevice is the main route of entry of PMNL to the oral cavity and that the numbers of PMNL migrating to the crevice increase as the gingival index rises.