The Extent of Endotoxin Penetration into Periodontitis-involved Teeth

Abstract

This study was performed to investigate the extent of endotoxin penetration into root surfaces.
At first, the depth after each scaling stroke performed with a hand instrument was measured on the root surface of the extracted teeth using a modified -micrometer . Then the extent of endotoxin penetration was assessed in 57 periodontitis-involved teeth. These teeth had no history of periodontal therapy and had been diagnosed as hopeless, requiring extraction. They were divided into two groups the first group consisted of 30 teeth, the second (27). The root surfaces were distinguished into 3 areas; supragingival exposed root surfaces, subgingival root surfaces and unexposed root surfaces. Each surface was scaled with 2 strokes (the first layer), 3 strokes (the second layer), 4 strokes (the third layer) and finally 4 strokes (the fourth layer). The scaled root debris was collected in each case. The endotoxin content of each layer and the calculus was assayed by pyrodick ® after extraction of the endotoxin by the hot-phenol water method according to Westphal and Jann.
It was found that the depth of the root surface after scaling was about 30μm at the first and second strokes, and about 20μm after the third stroke. The amounts of endotoxin were 452.9ng/g (the first group) and 368.1ng/g (the second group) in the calculus, 882.2ng/g (the first group) and 1185.0 ng/g (the second group) in the first layer of supragingival exposed root surfaces, 625.0ng/g (the first group) and 703.0ng/g (the second group) in the first layer of subgingival exposed root surfaces. They were about 7.4 to 24 times higher than that of other layers in which the amount was 49.6ng/g on average.
These results suggest that two scaling strokes with a sharp hand scaler are enough to eliminate endotoxin in periodontitis-involved root surfaces.