TITLE OF THE TOPIC: IN VIVO EVALUATION OF ACCURACY OF WORKING LENGTH DETERMINATION USING A NEW ELECTRONIC APEX LOCATOR ON VITAL UNINFECTED TEETH AND TEETH WITH RADIOGRAPHIC EVIDENCE OF PERIAPICAL LESIONS.
BRIEF RESUME OF INTENDED WORK
6.1. NEED FOR THE STUDY:
Accurate determination of working length during root canal treatment has always been a challenge in clinical endodontics. The cementoenamel junction where the pulp tissue changes into the apical tissue is the most ideal physiologic limit of the working length. It is also referred as the minor diameter or the apical constriction.
The electronic apex locator has attracted great deal of attention. It is one of the breakthrough that brought electronic science into the traditionally radiograph dependant endodontic practice.
Teeth with periapical radiolucency with radiographic indication of periapical lesion is said to shorten the working length by as much as two millimeters to that of normal working length6
The purpose of this study is to measure the accuracy of working length determination using IPEX (NSK,JAPAN) a new electronic apex locator in vital uninfected teeth and teeth with radiographic evidence of 5 to 10 millimeters of periapical lesions.
6.2. REVIEW OF LITERATURE:
An in-vivo study was done to compare the canal length determined by apex locator to the apical constriction in both vital and necrotic canals with the evidence of lesion. It was concluded that there was no statistical differences between the ability of apex locator to determine the apical constriction in vital canals versus necrotic canals1.
An in-vivo study was done to know the accuracy in vital and necrotic canals with an ENDEX apex locator with the radiographic evidence of lesions. It was concluded that all measurements were within a narrow range. There were no significant statistical differences in measurements between vital and necrotic canals2.
An in-vivo study was done in comparison of working length determination using two ROOT ZX and RAYPEX apex locators. It was concluded that no significant difference between electronic apex locators regarding working length determination of minor foramen3.
A study was done to evaluate the accuracy of the apex locator to determine the working length determination with simulated apical root resorption. It was concluded that no significant differences were seen regarding working length determination4.
An Ex-vivo study was done to know the accuracy of three electronic apex locators. It was concluded that the apex locators determined the canal length within 0.5mm from the apical constriction in majority of the cases5.
6.3. OBJECTIVE OF STUDY:
The objective of this study is to measure the accuracy of working length determination using IPEX (NSK, JAPAN) a new electronic apex locator in vital uninfected teeth and teeth with radiographic evidence of 5 to 10 millimeters of periapical lesions.
Forty teeth with single canal of patients which are advised for extraction, will be taken from department of oral and maxillofacial surgery, Rajarajeshwari dental college and hospital, Bangalore.
METHOD OF COLLECTION OF DATA:
Twenty teeth with single canal, matured apices which are vital and uninfected and twenty adult patients with mature apices with lesion of five to ten millimeters in diameter are taken for this study.
Teeth with single canal advised for extraction either vital uninfected teeth or teeth with radiographic evidence of periapical lesions.
Pregnant patients, teeth with calcified canals, teeth with external or internal resorption, retreatment cases, teeth of immature apex and teeth with fracture and mutilated teeth were excluded from this study.
Twenty healthy adult patients where extraction are advised for teeth with single canal which is vital and uninfected and 20 healthy adult patients with single canal with mature apices with lesion of 5 to 10 millimeters in diameter are taken for this study.
Approval by institutional review and ethical board before commencement of study obtained. The teeth have formed complete apices and confirmed by radiographic evaluation before treatment.
After local anesthesia is appropriately administered by an oral surgeon, experimental teeth are isolated with rubber dam.
The cusps are flattened to create a proper reference point with a sterile tapered fissure bur. [Horico diamond,Hopf and Ringler,Germany] Endodontic access is made into the pulp chamber with a sterile round bur.. The pulp is considered vital if bleeding is present upon entering the chambers. The canals will be irrigated with 2.5% sodium hypochlorite. In vital teeth pulp from the pulp space is removed with barbed broach and in non vital teeth, canals will be debrided. Gates glidden 1 and 2[Mani, inc, Tochigi, Japan] are used. Number 10 k file is used to determine the apical patency of the canal. Number 15 k file is used to determine working length. X-rays are taken to know the working length using Ingle`s method, followed by determination using IPEX [NSK, Nakanishi, Japan] apex locator and the data is duly entered.
Tooth collected after extraction by oral surgeon are collected and stored in saline. Tooth is washed and observed under magnification. Number 15 K file is pressed till the emergence of tip is seen and accuracy of apex locator is measured under proper illumination and 20x magnification.
7.3. DOES THE STUDY REQUIRE ANY INVESTIGATION OR INTERVENTIONS TO BE CONDUCTED ON PATIENTS OR OTHER HUMANS OR OTHER ANIMALS?
The procedure is explained and written consent is taken from the patient. Proper and
necessary protection in the form of providing double lead apron for the body and also
lead thyroid collar.
7.4. HAS ETHICAL CLEARANCE BEEN OBTAINED FROM YOUR INSTITUTION IN CASE OF 7.3?
LIST OF REFERENCES: 1. Craig A. Dunlap, Nijole A. Remeikis, Ellen A.Begole and Cindy R.
Rauschenberger. An In Vivo Evaluation of an electronic Apex Locator that uses the
ratio method in vital and Necrotic Canals. JOE 1998;24(1):48-50.