Abstract
Introduction
Working length determination is a crucial step for success of pulpectomy. Various new modalities have been developed. The newest technology includes EAL. Electronic apex locators require less chair side time, do not produce pain and avoid unnecessary radiation which makes it more superior in paediatric endodontic procedures.
Aim
To evaluate and compare Root ZX mini apex locator and Radiovisiography (RVG) for determining working length in primary molars.
Materials and methods
A sample of 30 primary molar teeth was subjected to working length determination by Root ZX mini and RVG. The data was collected and then tabulated and subjected to statistical analysis.
Results
On comparison among two groups, it was found there was no difference between the efficiency of modalities. A positive correlation was seen among Root ZX mini and RVG (ICC = 0.99).
Conclusion
Root ZX mini and radiovisiography are seen to be precise in determination of working length in primary molars. It can be said that Root ZX mini i. e the electronic apex locators can be used as an adjunct to Radiovisiography and conventional radiography.
Keywords: Apex locators, Pulpectomy, Radiovisiography, Root ZX mini, Working length
1. Introduction
Endodontic treatment of primary teeth provides a mechanism to maintain the teeth in the dentition until their normal exfoliation time.1 However, a radiographic image provides only a two-dimensional image of three dimensional structures, giving limited information about apical foramen and has other disadvantages and constraints such as limited mouth opening of children, poor patient co-operation, increasing appointment time and exposure to ionizing radiations.2
Electronic apex locators do not produce pain, help to reduce the treatment time, and help avoid unnecessary radiation which makes it more superior in pediatric endodontic procedures. Thus, they are recommended for endodontic treatment in children.4
Few in vitro studies conducted using Root ZX mini apex locator showed an accuracy of 96.2%.3,4 But on literature search it was found that there is a scarce literature about in vivo studies. So, we have designed this In Vivo study to compare and evaluate Root ZX mini apex locator and RVG for working length determination in primary teeth.
2. Materials and Methods
Ethical clearance was obtained from institutional review board. Subjects for the study were selected according to the inclusion and exclusion criteria. Consent and assent of the patients and parents were obtained. It is prospective study.
2.1. Inclusion criteria
Children between- 4–8 years whose Frankl’s behavior rating scale was Definitely positive (++), Positive (+) with primary molars indicated for Pulpectomy having minimum two third of root length remaining.5
2.2. Exclusion criteria
Primary molars with developmental anomalies, Primary molars with caries involving furcation, Children with systemic diseases and special health care needs, Primary molars with calcified root canals, Evidence of root fracture, trauma.
3. Methodology
A case history was recorded in a special format prepared for this study. The extent for caries and the root canal anatomy was assessed with pre-operative intra oral radiographs with 5 mm stainless steel wire for assessing any change in angulation during the analysis of subsequent radiovisiographs.
For the selected cases Local anaesthesia was administered using 2% lignocaine with adrenaline (1:80,000). The teeth were then isolated with rubber dam. Deep caries were excavated with a spoon excavator, first removing peripheral caries then proceeding towards the pulp. The remaining caries was removed using no. 330 tungsten carbide bur. A No. 2 straight fissure bur in a slow speed handpiece was used to remove the roof of pulp chamber.6
Removal of the coronal pulp was done with a large excavator or a slowly rotating no. 4 round bur following which the canal was negotiated using K-File and the radicular pulp was removed.10 Each of the selected tooth was then subjected to working length determination by two modalities namely Root ZX mini® apex locator and Radiovisiography.
The electronic working length was determined by using Root ZX mini® apex locator. The ground lead of the locator was placed on each patient’s labial commissure and endodontic file was clasped to the opposite electrode. The K-file was advanced apically until the apex locator signals that the apex has been reached.7 Three measurements were recorded for each root and the mean of it was considered as working length which was recorded in the master chart.
The digital radiograph was obtained using a computed dental radiography system, #1 sensor and X-ray system using paralleling technique. The position and angulation was kept constant throughout the study using Rinn XCP film Holder.8 Working length was determined using K- File, the Electronic ruler which is available in the software was used for the measurement of working length. The calibration of working length on radiovisiograph was done by placement of 5 mm stainless steel wire (0.7 mm) on the sensor vertically. After the radiovisiograph is taken, calibration was done and then the length was measured on the screen by the Kodak software. The correction of any change in angulation if present was done by measuring the change in dimension of the 5 mm wire and then adjusting the working length proportionally.9, 10, 11 The actual working length was calculated by using Ingle’s method and in cases of resorption Weine’s correction was used.12 Two trained examiners recorded the working length independently and the measurements were put in the master chart. After the measurements, pulp debridement was carried out in conjunction with copious irrigation followed by obturation with a biocompatible material. Final restorations were done with stainless steel crown.
3.1. Sample size estimation
The estimated sample size is 30 patients and was calculated using a formula.
Where.
ρ0 = 0, ρ1 = 0.754, Z1-α/2 = 2.58, Z1-β = 1.682
n = sample size
ρ0: Population correlation coefficient.
ρ1: Sample correlation coefficient.
α: Significance level.
1-β: Power.
3.2. Statistical analysis
The data obtained was statistically analyzed using SPSS Software Version 20. Level of significance was set at p = 0.05. Following tests were used dependent t-test, Kolmogorov Simonov test, Karl Pearson’s correlation coefficient and Kappa statistics.
4. Results
It was seen that out of thirty participants sixteen participants were male (53.33%) and fourteen participants were female (46.67%). Participants ranged from ages 4–8 years. The mean age of the participants was seen to be 6.03 years with a standard deviation of 1.35 years.
On comparison of RVG and Root ZX mini methods the results show that there was statistically significant difference in working length determination by RVG and ROOT ZX Mini in canal 1 (0.0023∗), canal 2 (0.0091∗), canal 3 (0.0004∗) where the standard deviation for Root ZX mini was less when compare to RVG(Table 1, Graph 1). However, there was no statistically significant difference seen when average was taken. Master chart showing the values for various canals (Table 2a, Table 2b, Table 2ca, 2b, 2c).
Table 1.
Table showing comparison of RVG and Root ZX mini methods with respect to working length at canal 1, canal 2, canal 3 and their average by dependent t-test.
| Canals | Methods | Mean | Std. Dv. | Mean Diff. | SD Diff. | Paired t | P-value |
|---|---|---|---|---|---|---|---|
| Canal 1 | RVG | 11.50 | 1.15 | ||||
| Root ZX mini | 11.25 | 1.07 | 0.25 | 0.41 | 3.3397 | 0.0023a | |
| Canal 2 | RVG | 11.42 | 1.14 | ||||
| Root ZX mini | 11.23 | 1.01 | 0.18 | 0.36 | 2.7956 | 0.0091a | |
| Canal 3 | RVG | 12.03 | 1.27 | ||||
| Root ZX mini | 11.68 | 1.35 | 0.35 | 0.48 | 4.0261 | 0.0004a | |
| Average | RVG | 11.49 | 1.06 | ||||
| Root ZX mini | 11.52 | 1.09 | −0.03 | 0.15 | −1.0871 | 0.2859 |
∗p < 0.05.
Canal 1: Mesiobuccal in Maxillary and Mandibular Molars, Canal 2 (Distobuccal in Maxillary and Mesiolingual in Mandibular Molars), Canal 3 (Palatal in Maxillary and Distal In Mandibular Molars).
Graph 1.
Graph showing comparison of RVG and Root ZX mini methods with respect to working length at canal1, canal 2, canal 3 and their average by dependent t-test.
Table 2a.
Table showing master chart for working length determination using Root ZX mini and RVG for canal 1.
| Canal 1 (Mesiobuccal in Maxillary and Mandibular Molars) | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Sr. No. | Age | Tooth No. | Gender | Examiner 1 | Examiner 2 | RVG | Reading 1 | Reading 2 | Reading 3 | Root ZX mini |
| 1 | 4 | 55 | F | 12.0 | 14.0 | 13.5 | 13.0 | 13.0 | 13.0 | 13.0 |
| 2 | 4 | 54 | F | 12.0 | 12.0 | 12.0 | 12.5 | 12.5 | 12.5 | 12.5 |
| 3 | 4 | 54 | F | 12.0 | 12.0 | 12.0 | 11.5 | 11.5 | 11.5 | 11.5 |
| 4 | 4 | 54 | M | 13.0 | 13.0 | 13.0 | 13.0 | 13.0 | 13.0 | 13.0 |
| 5 | 4 | 55 | M | 12.0 | 12.5 | 12.5 | 12.0 | 12.0 | 12.0 | 12.0 |
| 6 | 5 | 55 | M | 11.0 | 11.0 | 11.0 | 10.5 | 10.5 | 10.5 | 10.5 |
| 7 | 5 | 55 | F | 12.0 | 12.5 | 12.5 | 12.5 | 12.5 | 12.5 | 12.5 |
| 8 | 5 | 64 | M | 13.0 | 13.0 | 13.0 | 12.0 | 12.0 | 12.0 | 12.0 |
| 9 | 5 | 64 | M | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 |
| 10 | 5 | 65 | F | 12.0 | 12.5 | 12.5 | 11.5 | 11.5 | 11.5 | 11.5 |
| 11 | 5 | 65 | M | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 |
| 12 | 6 | 65 | F | 12.0 | 12.0 | 12.0 | 11.0 | 11.0 | 11.0 | 11.0 |
| 13 | 6 | 74 | M | 11.0 | 11.5 | 11.5 | 11.5 | 11.5 | 11.5 | 11.5 |
| 14 | 6 | 74 | F | 12.0 | 12.5 | 12.5 | 12.5 | 12.5 | 12.5 | 12.5 |
| 15 | 6 | 74 | F | 11.0 | 11.0 | 11.0 | 10.5 | 10.5 | 10.5 | 10.5 |
| 16 | 6 | 75 | M | 12.0 | 12.0 | 12.0 | 11.5 | 11.5 | 11.5 | 11.5 |
| 17 | 6 | 75 | M | 13.0 | 13.0 | 13.0 | 12.5 | 12.5 | 12.5 | 12.5 |
| 18 | 6 | 75 | F | 12.0 | 12.5 | 12.5 | 12.0 | 12.0 | 12.0 | 12.0 |
| 19 | 7 | 75 | M | 11.0 | 11.0 | 11.0 | 10.5 | 10.5 | 10.5 | 10.5 |
| 20 | 7 | 75 | M | 10.0 | 10.0 | 10.5 | 10.5 | 10.5 | 10.5 | 10.5 |
| 21 | 7 | 84 | F | 10.0 | 10.0 | 10.0 | 10.5 | 10.5 | 10.5 | 10.5 |
| 22 | 7 | 84 | M | 10.0 | 10.5 | 10.5 | 10.0 | 10.0 | 10.0 | 10.0 |
| 23 | 7 | 84 | F | 13.0 | 13.0 | 13.0 | 13.0 | 13.0 | 13.0 | 13.0 |
| 24 | 7 | 84 | M | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 |
| 25 | 7 | 85 | F | 10.0 | 10.5 | 10.5 | 10.5 | 10.5 | 10.5 | 10.5 |
| 26 | 8 | 85 | M | 10.0 | 10.0 | 10.0 | 10.5 | 10.5 | 10.5 | 10.5 |
| 27 | 8 | 85 | M | 9.5 | 9.5 | 9.5 | 9.5 | 9.5 | 9.5 | 9.5 |
| 28 | 8 | 85 | F | 11.0 | 11.0 | 11.0 | 10.5 | 10.5 | 10.5 | 10.5 |
| 29 | 6 | 85 | M | 10.0 | 10.0 | 10.0 | 10.0 | 10.0 | 10.0 | 10.0 |
| 30 | 6 | 85 | F | 9.5 | 9.5 | 9.5 | 9.0 | 9.0 | 9.0 | 9.0 |
Table 2b.
Table showing master chart for working length determination using Root ZX mini and RVG for canal 2.
| Canal 2 (Distobuccal in Maxillary and Mesiolingual in Mandibular Molars) | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Sr. No. | Age | Tooth No. | Gender | Examiner 1 | Examiner 2 | RVG | Reading 1 | Reading 2 | Reading 3 | Root ZX mini |
| 1 | 4 | 55 | F | 13.0 | 13.0 | 13.0 | 13.0 | 13.0 | 13.0 | 13.0 |
| 2 | 4 | 54 | F | 12.5 | 12.5 | 12.5 | 12.5 | 12.5 | 12.5 | 12.5 |
| 3 | 4 | 54 | F | 12.0 | 12.0 | 12.0 | 11.5 | 11.5 | 11.5 | 11.5 |
| 4 | 4 | 54 | M | 13.0 | 13.0 | 13.0 | 13.0 | 13.0 | 13.0 | 13.0 |
| 5 | 4 | 55 | M | 13.0 | 13.0 | 13.0 | 12.0 | 12.0 | 12.0 | 12.0 |
| 6 | 5 | 55 | M | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 |
| 7 | 5 | 55 | F | 13.0 | 13.0 | 13.0 | 12.5 | 12.5 | 12.5 | 12.5 |
| 8 | 5 | 64 | M | 13.0 | 13.0 | 13.0 | 12.0 | 12.0 | 12.0 | 12.0 |
| 9 | 5 | 64 | M | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 |
| 10 | 5 | 65 | F | 12.5 | 12.5 | 12.5 | 12.5 | 12.5 | 12.5 | 12.5 |
| 11 | 5 | 65 | M | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 |
| 12 | 6 | 65 | F | 12.0 | 12.0 | 12.0 | 11.0 | 11.0 | 11.0 | 11.0 |
| 13 | 6 | 74 | M | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 |
| 14 | 6 | 74 | F | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 |
| 15 | 6 | 74 | F | 11.5 | 11.5 | 11.5 | 11.5 | 11.5 | 11.5 | 11.5 |
| 16 | 6 | 75 | M | 12.0 | 12.0 | 12.0 | 11.5 | 11.5 | 11.5 | 11.5 |
| 17 | 6 | 75 | M | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 |
| 18 | 6 | 75 | F | 12.5 | 12.5 | 12.5 | 12.0 | 12.0 | 12.0 | 12.0 |
| 19 | 7 | 75 | M | 10.5 | 10.5 | 10.5 | 10.5 | 10.5 | 10.5 | 10.5 |
| 20 | 7 | 75 | M | 10.5 | 10.5 | 10.5 | 10.5 | 10.5 | 10.5 | 10.5 |
| 21 | 7 | 84 | F | 10.0 | 10.0 | 10.0 | 10.5 | 10.5 | 10.5 | 10.5 |
| 22 | 7 | 84 | M | 11.0 | 11.0 | 11.0 | 10.5 | 10.5 | 10.5 | 10.5 |
| 23 | 7 | 84 | F | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 |
| 24 | 7 | 84 | M | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 |
| 25 | 7 | 85 | F | 10.5 | 10.5 | 10.5 | 10.0 | 10.0 | 10.0 | 10.0 |
| 26 | 8 | 85 | M | 10.0 | 10.0 | 10.0 | 10.0 | 10.0 | 10.0 | 10.0 |
| 27 | 8 | 85 | M | 10.0 | 10.0 | 10.0 | 10.0 | 10.0 | 10.0 | 10.0 |
| 28 | 8 | 85 | F | 10.0 | 10.0 | 10.0 | 10.0 | 10.0 | 10.0 | 10.0 |
| 29 | 6 | 85 | M | 10.0 | 10.0 | 10.0 | 10.0 | 10.0 | 10.0 | 10.0 |
| 30 | 6 | 85 | F | 10.0 | 10.5 | 10.5 | 10.0 | 10.0 | 10.0 | 10.0 |
Table 2c.
Table showing master chart for working length determination using Root ZX mini and RVG for Canal 3.
| Canal 3 (Palatal in Maxillary and Distal In Mandibular Molars) | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Sr. No. | Age | Tooth No. | Gender | Examiner 1 | Examiner 2 | RVG | Reading 1 | Reading 2 | Reading 3 | Root ZX mini |
| 1 | 4 | 55 | F | 14.0 | 14.0 | 14.0 | 14.0 | 14.0 | 14.0 | 14.0 |
| 2 | 4 | 54 | F | 13.0 | 13.0 | 13.0 | 13.0 | 13.0 | 13.0 | 13.0 |
| 3 | 4 | 54 | F | 13.0 | 13.0 | 13.0 | 13.0 | 13.0 | 13.0 | 13.0 |
| 4 | 4 | 54 | M | 15.0 | 15.0 | 15.0 | 15.0 | 15.0 | 15.0 | 15.0 |
| 5 | 4 | 55 | M | 13.0 | 13.0 | 13.0 | 13.0 | 13.0 | 13.0 | 13.0 |
| 6 | 5 | 55 | M | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 |
| 7 | 5 | 55 | F | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 |
| 8 | 5 | 64 | M | 14.0 | 14.0 | 14.0 | 14.0 | 14.0 | 14.0 | 14.0 |
| 9 | 5 | 64 | M | 13.0 | 13.0 | 13.0 | 13.0 | 13.0 | 13.0 | 13.0 |
| 10 | 5 | 65 | F | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 |
| 11 | 5 | 65 | M | 11.5 | 11.5 | 11.5 | 11.5 | 11.5 | 11.5 | 11.5 |
| 12 | 6 | 65 | F | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 | 12.0 |
| 13 | 6 | 74 | M | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 |
| 14 | 6 | 74 | F | 12.5 | 12.5 | 12.5 | 12.5 | 12.5 | 12.5 | 12.5 |
| 15 | 6 | 74 | F | 11.5 | 11.5 | 11.5 | 11.5 | 11.5 | 11.5 | 11.5 |
| 16 | 6 | 75 | M | 12.5 | 12.5 | 12.5 | 12.5 | 12.5 | 12.5 | 12.5 |
| 17 | 6 | 75 | M | 13.0 | 13.0 | 13.0 | 13.0 | 13.0 | 13.0 | 13.0 |
| 18 | 6 | 75 | F | 13.0 | 13.0 | 13.0 | 13.0 | 13.0 | 13.0 | 13.0 |
| 19 | 7 | 75 | M | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 |
| 20 | 7 | 75 | M | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 |
| 21 | 7 | 84 | F | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 |
| 22 | 7 | 84 | M | 11.5 | 11.5 | 11.5 | 11.5 | 11.5 | 11.5 | 11.5 |
| 23 | 7 | 84 | F | 13.0 | 13.0 | 13.0 | 13.0 | 13.0 | 13.0 | 13.0 |
| 24 | 7 | 84 | M | 13.0 | 13.0 | 13.0 | 13.0 | 13.0 | 13.0 | 13.0 |
| 25 | 7 | 85 | F | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 |
| 26 | 8 | 85 | M | 10.5 | 10.5 | 10.5 | 10.5 | 10.5 | 10.5 | 10.5 |
| 27 | 8 | 85 | M | 10.0 | 10.0 | 10.0 | 10.0 | 10.0 | 10.0 | 10.0 |
| 28 | 8 | 85 | F | 10.0 | 10.0 | 10.0 | 10.0 | 10.0 | 10.0 | 10.0 |
| 29 | 6 | 85 | M | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 | 11.0 |
| 30 | 6 | 85 | F | 10.0 | 10.5 | 10.5 | 10.0 | 10.0 | 10.0 | 10.0 |
When the correlation between RVG and Root ZX mini methods with respect to working length at canal1, canal 2, canal 3 and their average by Karl Pearson’s correlation coefficient was done It was seen that good correlation exists between RVG and Root ZX Mini in all the canals and it was found to be statistically significant (p = 0.0001∗) (Table 3).
Table 3.
Table showing correlation between RVG and Root ZX mini methods with respect to working length at canal1, canal 2, canal 3 and their average by Karl Pearson’s correlation and inter examiner agreement with respect to working length at canal1, canal 2, canal 3 and their average by Kappa statistic.
| Canals | Correlation between RVG and Root ZX mini methods with respect to working length by Karl Pearson’s correlation coefficient |
||
|---|---|---|---|
| r-value | t-value | p-value | |
| Canal 1 | 0.9346 | 13.8978 | 0.0001∗ |
| Canal 2 | 0.9507 | 16.2175 | 0.0001∗ |
| Canal 3 | 0.9356 | 14.0221 | 0.0001∗ |
| Average | 0.9900 | 37.0720 | 0.0001∗ |
| Canals |
Inter examiner Agreement by Kappa statistic |
|||||
|---|---|---|---|---|---|---|
| Agreement |
Expected Agreement |
Kappa | Std. Err. | Z-value | p-value | |
| Canal 1 | 92.22% | 71.85% | 0.7237 | 0.1128 | 6.4100 | 0.0001∗ |
| Canal 2 | 93.81% | 66.22% | 0.8167 | 0.1167 | 7.0000 | 0.0001∗ |
| Canal 3 | 93.64% | 73.92% | 0.7560 | 0.1106 | 6.8300 | 0.0001∗ |
| Average | 95.98% | 69.64% | 0.8675 | 0.1129 | 7.6800 | 0.0001∗ |
The inter examiner agreement with respect to working length at canal1, canal 2, canal 3 and their average by Kappa statistic showed a positive correlation (Table 3).
5. Discussion
Primary teeth are said to play a pivotal role in dental development. If premature loss of these teeth occurs it can lead to space closure leading to malocclusion in permanent dentition. There are various procedures that are used to preserve the teeth which include indirect pulp capping, pulpotomy, pulpectomy etc.13
Pulpectomy is a procedure which includes complete removal of coronal as well as radicular pulp. One of the most important steps for pulpectomy treatment to be success is working length determination. Working length determination is done to establish the position of the apical foramen and hence extent of the obturation. Various modalities have been developed over the years for working length determination.14, It is seen from earlier literature that radiographs are 81.6% accurate in determination of working length in permanent teeth.15
5.1. Justification for the study
Various studies have been conducted on use of apex locators and conventional radiography in permanent teeth and showed that the EAL’s were more efficient when compared to radiography.
Scarce literature is present when the same is considered for primary molars. Hence, in this study a comparison was carried out between the same two modalities in primary molars. It was seen that there was no statistically significant difference between Root ZX mini apex locator and Radiovisography when it comes to working length determination in primary molars. It states that EAL can be used and are equally efficient in primary molars even though there is presence of physiologic root resorption.
Various studies found in literature comparing radiography and EAL’s showed similar results when done in permanent teeth. A study was conducted by Orosco et al. where he compared Root ZX with radiography in determining the working length in permanent teeth. It was seen that the conventional radiography an EAL were more efficient that digital radiography.20
In accordance to above stated studies our study showed that, when the measurements of RVG were compared with EAL for the tooth as a whole for primary teeth, the results obtained showed no statistically significant difference. It was seen that RVG and Root ZX mini both had equal efficacy in primary teeth when compared to permanent teeth.
However, Sara et al. found out that Root ZX was most accurate followed by the Radiography and least accurate was tactile sense in permanent teeth. She found that the Root ZX was able to locate the apex in within 0.5 mm in almost 143 out 150 cases (95%), this was seen in case of permanent teeth.20
On the contrary our study showed that when primary molars are considered as a whole both RVG and Root ZX mini showed no statistically significant difference, but when individual canals are compared for the primary teeth there is statistically significant difference seen between EAL and RVG, in which the standard deviation for Root ZX Mini was less as compared to RVG. Hence it can be said that Root ZX mini showed more accuracy as compared to RVG. This was similar to the studies stated above. This is one of study that compares fifth generation apex locator with the Radiovisiography hence this study is different from other studies.
In 1963 Electronic apex locators started gaining popularity due to its ease of use, compact size and decreased exposure to ionizing radiation. In this study Root ZX Mini a fourth generation electronic apex locator has been used. These apex locators are said to be similar to impedance type.16 The main principle of this generation EAL is that it measures the impedance of tooth at two different frequencies. As the file is seen to proceed apically, difference among the impedance values is seen and keeps changing. It is seen that at apex this difference in the impedance value is maximum.17 At each frequency impedance of the model is measured and file position is determined from these two impedances ratio.18 Root ZX mini was seen to be more advantageous because of its compact design, ease of use.19 Hence in this study the comparison was made between Root ZX Mini and RVG.
In the present study, when the working length determination is compared among each canal:
For mesio buccal canal of Maxillary and mandibular molars p = 0.0023, for palatal canal of maxillary and distal canal of mandibular molars p = 0.0091 for distobuccal of maxillary and mesiolingual of mandibular molars p = 0.0004. Hence, a statistically significant (p < 0.05) difference was seen. Karl Pearson’s coefficient test showed a 99% co relation between radiovisiography and Root ZX mini (ICC = 0.9900). The electronic apex locator showed good reliability when compared to RVG. It is also seen that when the actual reading was at the 0 mark instead of the apex mark more accurate results were obtained.
Limitations of the study include incorporation of larger sample size and comparison with newer generation of electronic apex locators.
For future prospects, as the fourth generation of electronic apex locators showed reliable results, further studies can be carried out for its comparison with newer generations of electronic apex locators.
6. Conclusion
-
•
Radiovisiography and EAL showed same results and were comparable.
-
•
There was a positive co-relation seen between Radiovisiography and Root ZX mini.
-
•
As the Root ZX mini and radiovisiography are seen to be precise in determination of working length in primary molars. It can be said that Root ZX mini i. e the electronic apex locators can be used as an adjunct to Radiovisiography.
Contributors
Rucha N. Davalbhakta: Concepts, Design, Definition of intellectual content, Literature search, Clinical studies, Experimental studies, Data acquisition, Data analysis, Statistical analysis, Manuscript preparation, Manuscript editing, Manuscript review, Guarantor. Niraj S. Gokhale: Concepts, Design, Definition of intellectual content, Clinical studies, Experimental studies, Data analysis, Manuscript preparation, Manuscript editing, Manuscript review, Guarantor. Shivayogi M. Hugar: Concepts, Design, Experimental studies, Manuscript editing, Manuscript review. Chandrashekhar M. Badakar: Concepts, Experimental studies. Gowtham A: Experimental studies, Manuscript editing, Manuscript review. Sanjana P. Soneta: Literature search, Clinical studies.
Source(s) of support
Nil.
Declaration of competing interest
Nil.
References
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