Effect of needle tip design and position, and irrigant flow rate on apical pressure
10.14815/kjdm.2018.45.4.275
- Author:
Chang Ha LEE
1
;
Seol Ah JO
;
Bum Soon LIM
;
In Bog LEE
Author Information
1. Department of Conservative Dentistry, School of Dentistry, Seoul National University, Seoul, Korea. inboglee@snu.ac.kr
- Publication Type:Original Article
- Keywords:
Apical pressure;
Irrigant flow rate;
Needle tip design and position
- MeSH:
Bicuspid;
Central Venous Pressure;
Constriction;
Dental Pulp Cavity;
Humans;
Needles
- From:
Korean Journal of Dental Materials
2018;45(4):275-286
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
The purpose of this study was to evaluate the effect of needle tip design and position, and irrigant flow rate on apical pressure (AP) during root canal irrigation. Five human mandibular premolars were instrumented up to #35 (0.06 taper) using nickel-titanium rotary instruments. Three different needles according to change of needle tip design (notched, side-vented, and flat) were positioned at the point of 1, 3, and 5 mm from the apical constriction (needle tip position). For each needle tip design and position, APs were measured with varying flow rates of 0.05, 0.1, 0.2, and 0.3 ml/s. When the other conditions were controlled, AP increased with decreasing needle tip position or increasing irrigant flow rate (p < 0.05). The AP of flat needle was the highest, followed by notched, side-vented needle for the same needle tip position and irrigant flow rate. The APs at needle tip position of 1 mm or with more than 0.1 ml/s flow rate were higher than central venous pressure (5.88 mmHg) for all conditions. Flat needle was not recommended for clinical use due to sharp increase of AP with changing needle tip position and irrigant flow rate. For safe and effective root canal irrigation, irrigant should be applied with the needle tip position of 3 mm and flow rate of less than 0.05 ml/s.
