Pressures recorded during periodontal pocket irrigation.

Pressures arising during periodontal pocket irrigation with 5 ml and 20 ml disposable plastic syringes, a peristaltic pump and a Waterpik pulsating irrigator were measured with an in-line transducer and recorder in 11 patients. Three types of needles were used with each device; disposable 15-gauge straight and angled needles and a 15-gauge angled reusable needle. Measurements were made with the needle tips just within, and 3 mm into the pocket. With both the 5 ml and 20 ml syringes and all needles, pressures of 100- to 500-mm mercury were recorded. With the peristaltic pump, pressures of 70- to 340-mm mercury were recorded with all needles. The Waterpik apparatus produced pressures of not more than 60-mm mercury in all cases.

Quantitative assessment of tooth wear, alveolar-crest height and continuing eruption in a Romano-British population.

Although measurements from cement-enamel junction (CEJ) to alveolar crest (AC) have been used in assessing changes in alveolar-crest height as age or chronic inflammatory periodontal disease (CIPD) progresses, there is evidence from ancient populations that the position of AC remains almost constant throughout life and continuing eruption to compensate for attrition may explain why CEJ-AC measurements increase with age. Measurements of occlusal attrition and relationship of CEJ to AC were made on the cheek teeth of 500 Romano-British skulls by direct measurement or by reference to the fixed line of the inferior alveolar canal (IAC) on radiographs. Direct measurements indicated that there were usually no statistical differences between the vertical amounts of tooth substance lost by attrition and the change in the distance CEJ-AC as age progressed. Measurements on radiographs showed that posterior teeth continued to erupt to compensate for attrition and the AC remained static as age progressed. Bone deposition at the AC was seen in the majority of ground sections. Thus tooth wear appears to be compensated by continuing movement of teeth in an occlusal direction. The position of the AC remained almost constant throughout life; AC bone lost by CIPD seemed to be replaced during continuing tooth eruption.