Platelet-rich fibrin as an apical barrier for MTA placement in the treatment of teeth with open apices: a pilot study.

OBJECTIVE: The aim of the present pilot study was to assess the effectiveness of the platelet-rich fibrin (PRF) apical barrier for the placement of MTA for the treatment of teeth with periapical lesions and open apices. METHODS: A total of thirty teeth on twenty-eight patients with open apices and periapical periodontitis were enrolled and divided into two groups in the present pilot study. In the PRF group (fourteen teeth in thirteen patients), nonsurgical endodontic treatment was performed using PRF as an apical matrix, after which the apical plug of the MTA was created. For the non-PRF group (fourteen teeth in fourteen patients), nonsurgical endodontic therapy was performed using only the MTA for an apical plug with no further periapical intervention. Clinical findings and periapical digital radiographs were used for evaluating the healing progress after periodic follow-ups of 1, 3, 6, and 9 months. The horizontal dimension of the periapical lesion was gauged, and the changes in the dimensions were recorded each time. The Friedman test, Dunn-Bonferroni post hoc correction, and Mann-Whitney U test were used for statistical analysis, with P < 0.05 serving as the threshold for determining statistical significance. RESULTS: All patients in both groups in the present pilot study had no clinical symptoms after 1 month, with a significant reduction in the periapical lesion after periodic appointments. The lesion width of the PRF group was significantly smaller than that of the non-PRF group in the sixth and ninth month after treatment. CONCLUSIONS: PRF is a promising apical barrier matrix when combined with MTA for the treatment of teeth with open apices and periapical periodontitis. Small number of study subjects and the short time of follow-up period limit the generalizability of these results. TRIAL REGISTRATION: TCTR, TCTR20221109006. Registered 09 November 2022 - Retrospectively registered, https://www.thaiclinicaltrials.org/show/TCTR20221109006 .

The clinical outcomes of vital intact teeth close to large cystic lesions of endodontic origin: A prospective clinical study.

AIM: To evaluate the indication of the endodontic treatment for vital intact teeth with the root apex involved in large radicular cystic lesions of endodontic origin. METHODOLOGY: This prospective cohort study enrolled healthy participants with radicular cysts of endodontic origin and with the root apex of vital intact teeth involved in the bone defect, as determined by cone beam computed tomography (CBCT). Thirty-two sound vital teeth were analysed by thermal (TPT) and electric pulp tests (EPT) before surgery (T0) and 1 week (T1), 2 weeks (T2), 3 months (T3) and 6 months (T4) post-surgery. Student's t-test (p < .05) was used to compare the EPT values at baseline and T4. anova (p < .05) was used to analyse the EPT variations for all maxillary and mandibular teeth. McNemar test (p < .05) was used to compare the results according to variation in EPT values gathering by variation, no variation and no response. RESULTS: At T1, 75 and 65.7% of teeth responded positively whilst 25 and 34.3% did not respond to EPT and TPT, respectively. The variation of the EPT values between T0 and T1 was observed for 50.0% of teeth, whilst no variation was noticed in 25.0% of teeth. At T4, 90.6 and 87.5% of teeth responded positively whilst 9.4 and 12.5% did not respond to EPT and TPT, respectively. At T4, variation of the EPT values between T0 and T4 was observed for 28.1%, whilst no variation was noticed in 62.5% of teeth. There were no statistical differences in EPT results between T0 and T4 (p > .05), but significant differences were observed for EPT values between T1 and T4 (p < .05), and between mandibular and maxillary teeth. The pulp sensibility of maxillary teeth worsened after surgery, before reverting progressively to T0 values, whilst no statistically significant differences were observed for mandibular teeth at the different time points. CONCLUSIONS: These data support the inconsistence of the prophylactic endodontic treatment in healthy vital teeth with apex involvement in large cystic lesions of endodontic origin. Post-surgery follow-up with TPT and EPT is recommended to assess pulp status.

The effect of root canal preparation tapers on planktonic bacteria and biofilm reduction in the apical third: A correlative microtomography and microbiological laboratory study.

AIM: To evaluate the influence of different preparation tapers on the reduction in planktonic bacteria and biofilms of Enterococcus faecalis and Candida albicans in the apical third (4 mm) of the mesial roots of mandibular molars, correlating decontamination with canal shape. METHODOLOGY: After microtomography analysis for morphological standardization of the canals, 48 mandibular molar roots, each containing two canals (96 canals), were contaminated with E. faecalis and C. albicans and divided into four groups (n = 11) for canal instrumentation using ProDesign Logic 2 files with different tapers G (.03): # 25.03; G (.04): # 25.04; G (.05): # 25.05; and G (.06): # 25.06 and irrigation with 2.5% sodium hypochlorite. Four roots were examined under a scanning electron microscope (SEM) to qualitatively assess biofilm formation. Eight roots were used as the negative control group (samples were not contaminated). Bacteriological samples were taken exclusively from the apical third of the roots before and after chemical-mechanical preparation and bacterial counts were determined (CFU/mL). The final micro-CT scan was used to quantify the volume variation and unprepared canal area in the apical third. Statistical analysis was performed using the Kruskal-Wallis, Student-Newman-Keuls and Wilcoxon tests for analysis of microbiological data. anova and the Tukey or Games-Howell test were used for analysis of micro-CT data and Spearman's test for correlations (α = 5%). RESULTS: All groups showed a significant reduction in bacteria (p < .05), with no statistically significant difference between groups. There was no significant difference in per cent volume increase between groups. The unprepared area (Δ%) was affected by the file used (p = .026) and was significantly lower for G (.06) compared to G (.03). There was no statistically significant correlation among bacterial reduction, volume and unprepared area (p > .05). CONCLUSION: The different preparation tapers influenced root canal shaping in the apical third but did not improve decontamination in this region.

Treatment outcomes and prognostic factors of the apical barrier technique with premixed calcium silicate-based putty in necrotic permanent teeth with open apices: a retrospective cohort study with up to six years follow-up.

OBJECTIVES: To evaluate treatment outcomes of the apical barrier technique with premixed calcium silicate-based putty for treating necrotic permanent teeth with open apices and to identify prognostic factors. MATERIALS AND METHODS: Permanent teeth with necrotic pulps and open apices treated by the apical barrier technique with premixed calcium silicate-based putty, with a minimum follow-up of 12 months, were included. Treatment outcomes were based on clinical signs, symptoms, and radiographic evaluation. The treatment outcome was dichotomized into success or failure according to strict and loose criteria. The chi-square test (or Fisher's exact test) and multiple logistic regression analysis were used to evaluate possible prognostic factors associated with treatment outcomes. RESULTS: Seventy-four teeth with a follow-up time of 12-72 months (mean, 25.74 ± 14.36 months) were included in the final evaluation. The success rate was 97.30% using the loose criteria and 66.22% using the strict criteria. Multiple logistic regression analysis indicated that the size of pre-operative periapical lesion (≥ 5 mm) (odds ratio [OR]: 18.96; P = 0.0153) and root canal underfilling (OR: 8.341; P = 0.0448) were significant predictors for treatment failure under the strict criteria. CONCLUSION: The apical barrier technique with premixed calcium silicate-based putty is a highly successful procedure for treating necrotic permanent teeth with open apices after an observation period of up to 6 years. Treatment success under the strict criteria is primarily affected by the size of the pre-operative periapical lesion and the apical extent of root-filling. CLINICAL RELEVANCE: Careful case selection and ensuring adequate root filling quality are essential to the successful outcome of the apical barrier technique with premixed calcium silicate-based putty.

In vitro evaluation of the accuracy of electronic apex locators and cone-beam CT in the detection of oblique root fractures.

OBJECTIVES: This study aimed to compare the accuracy of cone-beam CT (CBCT) scanning and 3 different electronic apex locators (EALs) in the detection of simulated oblique root fractures (ORF) in different localizations. METHODS: The study utilised a total of 80 human maxillary incisors, which were categorised into two groups based on the location of the ORF (apical and middle third of the root) formed on the buccal side of the root surface. The measurement of the distance between the incisal edge and the intersection of the ORF with the root canal was conducted using a stereomicroscope. This measurement is referred to as the actual working length (AWL). Additionally, three EALs-Dentaport ZX, EndoRadar Pro, and Propex II-were utilised to determine the electronic working length (EWL). Furthermore, CBCT images were employed to assess the distance, known as the CBCT working length (CWL). The differences were determined by subtracting AWL from EWL and CWL. RESULTS: Based on the accuracy of the devices, there were no significant differences observed among Dentaport ZX, EndoRadar, Propex II, and CBCT measures in both the apical and middle third ORF groups, within the acceptable range of 0.5 and 1 mm. CONCLUSIONS: The accuracy of Dentaport ZX, Propex II, and CBCT was higher in the middle third ORF group compared to the apical third ORF group, with a tolerance of 0.5 mm. However, there were no significant differences seen among the devices.

Exploring etiologic contributions to the occurrence of external apical root resorption.

INTRODUCTION: External apical root resorption (EARR) is often an undesirable sequela of orthodontic treatment. Prior studies have suggested a substantial link between EARR and certain genetic components. Single nucleotide polymorphisms (SNPs) may play a role as predisposing factors. This study aimed to investigate the potential association between EARR and various SNPs. METHODS: The study included 218 orthodontic participants of all malocclusions who had available pretreatment and posttreatment panoramic radiographs. The most severely affected maxillary incisor on the radiograph was assessed for EARR using a 0-4 categorical scale. DNA was taken from the saliva samples of the participants, and the SNPs were analyzed using polymerase chain reaction and TaqMan chemistry. Statistical testing was performed to verify any associations with EARR (P <0.05). RESULTS: From all genes tested, the rs678397 SNP of ACT3N (P = 0.003) and the rs1051771 SNP of TSC2 (P = 0.03) were significantly associated with EARR. No association could be established between other polymorphisms and EARR. In addition, patients with Class III malocclusion and extended treatment times were at increased risk of developing EARR. CONCLUSIONS: Our results support the concept of gene polymorphisms as risk factors in EARR. In particular, a significant association was found between ACT3N and TSC2 and EARR. Clinically, predisposing risk factors for EARR should be assessed for each patient.

Efficacy of electronic apex locators in comparison with intraoral radiographs in working length determination- a systematic review and meta-analysis.

BACKGROUND: Successful endodontic treatment needs accurate determination of working length (WL). Electronic apex locators (EALs) were presented as an alternative to radiographic methods; and since then, they have evolved and gained popularity in the determination of WL. However, there is insufficient evidence on the post-operative pain, adequacy, and accuracy of EALs in determining WL. OBJECTIVE: The systematic review and meta-analysis aims to gather evidence regarding the effectiveness of EALs for WL determination when compared to different imaging techniques along with postoperative pain associated with WL determination, the number of radiographs taken during the procedure, the time taken, and the adverse effects. METHODS: For the review, clinical studies with cross-over and parallel-arm randomized controlled trials (RCTs) were searched in seven electronic databases, followed by cross-referencing of the selected studies and related research synthesis. Risk of bias (RoB) assessment was carried out with Cochrane's RoB tool and a random-effects model was used. The meta-analysis was performed with the RevMan software 5.4.1. RESULTS: Eleven eligible RCTs were incorporated into the review and eight RCTs into the meta-analysis, of which five had high RoB and the remaining six had unclear RoB. Following meta-analysis, no significant difference in postoperative pain was found among the EAL and radiograph groups (SMD 0.00, CI .29 to .28, 354 participants; P value = 0.98). Radiograph group showed better WL accuracy (SMD 0.55, CI .11 to .99, 254 participants; P value = 0.02), while the EAL group had 10% better WL adequacy (RR 1.10, CI 1.03-1.18, 573 participants; P value = 0.006). CONCLUSION: We found very low-certainty evidence to support the efficacy of different types of EAL compared to radiography for the outcomes tested. We were unable to reach any conclusions about the superiority of any type of EAL. Well-planned RCTs need to be conducted by standardizing the outcomes and outcome measurement methods.

Platelet rich fibrin and MTA in the treatment of teeth with open apices.

BACKGROUND: The present study aimed to evaluate the effectiveness of using platelet-rich fibrin (PRF) as the apical matrix for the placement of MTA in nonsurgical endodontic therapy for teeth with periapical lesions and open apices. METHODS: Twelve teeth from eleven patients with periapical periodontitis and open apices were enrolled in the study. Nonsurgical endodontic therapy was performed with the PRF used as an apical barrier and the MTA manipulated as an apical plug for further thermoplasticized gutta percha in the remaining part of the root canal. Clinical signs and periapical digital radiographs were recorded and analyzed to evaluate the curing progress after periodical follow-ups of 1, 3, and 6 months. The horizontal dimension of the periapical lesion was determined, and the changes in the dimensions were recorded each time. The Friedman test was used for statistical analysis, with P < .05 serving as the threshold for determining statistical significance. RESULTS: All patients had no clinical symptoms after the first month of treatment, with a significant reduction in the periapical lesion after periodical appointments. CONCLUSIONS: PRF is an effective barrier when combined with MTA for the treatment of teeth with periapical periodontitis and open apices.

Panoramic evaluation of external root resorption in mandibular molars during orthodontic treatment: a comparison between root-filled and vital teeth treated with fixed appliances or clear aligners.

BACKGROUND: This investigation compared the extent of external apical root resorption (EARR) in root-filled teeth (RFT) and their contralateral vital pulp teeth (VPT) counterparts during orthodontic treatment (OT) with clear aligner (CA) treatment or fixed appliance (FA) treatment. METHODS: Sixty-six patients with similar baseline American Board of Orthodontics (ABO) discrepancy index scores were divided into two groups: 37 patients (21 females, 16 males; mean age 17.45 ± 2.67 years) in the FA group, and 29 patients (18 females, 11 males; mean age 18.33 ± 1.96 years) in the CA group. Digital panoramic radiographs captured pre- and post-OT were used to measure tooth lengths and root surface measurements in mandibular molars. EARR in both RFT and contralateral VPT was evaluated pre- and post-OT. Statistical analysis employed paired t-tests, independent t-tests, and analysis of covariance (ANCOVA) (p < .05). RESULTS: All teeth exhibited varying degrees of EARR following OT. FA treatment resulted in significantly longer treatment duration (p < .05) and greater EARR compared to CA treatment (p < .05). Moreover, statistically significant differences in EARR were observed within both groups between RFT and VPT (p < .05). CONCLUSIONS: Comparison of pre- and post-OT radiographs revealed different degrees of EARR in all teeth. CA treatment resulted in less frequent and less severe EARR compared to FA treatment. RFT demonstrated greater resistance to EARR than VPT in both treatment groups.

The usefulness of ultrasonography as a dynamic measurement system for visualizing root canal working length: an in vivo study.

OBJECTIVE: Although apex locators are generally effective tools for determining root canal working length, they may produce inaccurate results in some cases. The present study aimed to evaluate the efficacy of ultrasonography as an alternative method for measuring root canal length. MATERIALS AND METHODS: Forty-seven anterior teeth with apical lesions were selected for the study. Initially, an electronic apex locator was used to measure the working length. Subsequently, ultrasonography was employed to visualize the root apex and determine the working length. During ultrasound imaging, a K-file No. 15 was inserted into the root canal until its tip was visible on the ultrasound monitor. Measurements obtained from both methods were compared using an independent sample t-test. Correlations were assessed with the Pearson correlation coefficient, and agreement was determined using the Bland‒Altman plot. RESULTS: The mean working canal length was 19.9 mm for the apex locator and 20.6 mm for the ultrasonography-guided method. No significant differences were observed between the data obtained using the apex locator method and the data obtained using the ultrasonography guidance method. Furthermore, a high level of agreement was identified between the two techniques. CONCLUSION: Ultrasonography can be used to visualize the apex effectively and determine canal length, especially when canal length determination is uncertain for various reasons.

Comparative evaluation of the accuracy of electronic apex locators and cone-beam computed tomography in detection of root canal perforation and working length during endodontic retreatment.

BACKGROUND: To evaluate the accuracy of the electronic apex locators (EALs), and Cone-Beam Computed Tomography (CBCT) scanning, both in working length (WL) determination and in the detection of root canal perforations in retreatment cases. METHODS: Sixty human mandibular premolars were selected. After crown removal partially and canal access, root canals were instrumented and irrigated. The obturation process utilized gutta-percha and sealer with warm vertical compaction. Two groups were distinguished: one without perforation (Group 1) and the other with an apical third perforation (Group 2). Retreatment included filling removal, apical preparation, and irrigation. Actual working lengths (AWL) were determined using a stereomicroscope. CBCT images were used to measure CBCT working length (CWL), with adjustments for optimal views. Propex II and Dentaport ZX were used to measure electronic working length (EWL). Differences between EWL and AWL, as well as CWL, were analyzed to gauge accuracy. Data underwent Two-way ANOVA analysis. Measurements within ± 0.5 and ± 1 mm tolerance ranges were deemed successful for each device, followed by applying the Pearson Chi-square test. RESULTS: The study reveals no significant inter-group variations in device performance (p > .05). Dentaport ZX missed detecting perforation in two Group 2 (apical perforation) cases. For ± 1 mm tolerance, Propex II displayed the highest success in Group 2 (apical perforation). CONCLUSION: This study demonstrates the comparable performance of Propex II, Dentaport ZX, and CBCT in endodontic retreatment, providing insights into diagnostic reliability.

Evaluation of the Accuracy of Electronic Apex Locators in Modern Endodontics: An Umbrella Review.

Background and Objectives: To achieve success in endodontic treatment, it is essential to properly perform the steps of shaping, cleansing and obturation. Determining the working length of the canal is, therefore, a process that must be precise and accurate. Electronic apex locators are a useful tool for the clinician to best perform this step of endodontic treatment. Materials and Methods: The purpose of the following umbrella review is to evaluate, through data in the literature, the degree of accuracy of apex locators. Results: Seven systematic reviews were included in the following umbrella review. Five compare the accuracy of apex locators versus radiographic techniques, two compare different types of electronic apex locators, and two analyze the determination of working length in primary teeth. Conclusions: From the results obtained from the following umbrella review, albeit at low levels of evidence, the methods for determining working length using electronic apex locators and other methods, particularly using radiographic evaluation, are equally valid.

Measurement of the apical anatomy of immature maxillary central incisors using cone-beam computed tomography.

OBJECTIVE: To investigate the CBCT findings of the apical anatomy of immature maxillary central incisors. METHODS: CBCT images of 100 immature maxillary central incisors in Nolla 8 and 100 immature maxillary central incisors in Nolla 9 were collected. The mesiodistal and carniocaudal diameters of the apical foramen of immature maxillary central incisors were measured by software included with CBCT, as well as the mesiodistal, carniocaudal and facioligual diameters of the apical shadow. The apical shadow and apical foramen diameters were compared between Nolla 8 and Nolla 9. Data were analyzed using the MedCalc software package. RESULTS: For immature maxillary central incisors, the mesiodistal and facioligual diameters of the apical foramen were 2.75±0.68 mm and 3.28±0.74 mm in Nolla 8 and 1.50±0.51 mm and 1.92±0.79 mm in Nolla 9. The mesiodistal, facioligual and carniocaudal diameters of the apical shadow were 3.84±0.73 mm, 4.49±0.68 mm and 3.41±1.27 mm in Nolla 8 and 2.76±0.60 mm, 3.41±0.80 mm and 2.06±0.65 mm in Nolla 9, respectively. CONCLUSIONS: The immature maxillary central incisors in Nolla 8 have a larger apical shadow and apical foramen than those in Nolla 9. The apical region of the maxillary central incisors in Nolla 8 was more likely to have a broad, blurred lamina dura. With the development of the apical foramen, the lamina dura in the apical region tended to be clear and sharp. CLINICAL SIGNIFICANCE: To our knowledge, this is the first study to radiologically analyse the in vivo anatomy of the apical foramen and apical shadow of immature maxillary central incisors. The results of this study provide a more detailed understanding of the apical anatomy of the immature maxillary central incisor for the diagnosis and treatment of apical lesions.

Are electronic apex locators accurate in determining working length in primary teeth pulpectomies? A systematic review and meta-analysis of clinical studies.

BACKGROUND: The lack of a well-defined apical constriction in primary teeth raises concerns regarding the accuracy of electronic apex locators (EALs) for measuring working length. OBJECTIVES: To evaluate the accuracy of EALs in determining working length in primary teeth pulpectomies. METHODS: Two reviewers searched ten databases up to September 2021. Clinical studies evaluating the accuracy of the electronic measurement of working length in primary teeth pulpectomies were included. Studies without a comparison group, with samples smaller than ten root canals, and that did not use a multiple frequency EAL were excluded. A meta-analysis was conducted to assess the paired differences in mean lengths between measurements obtained by electronic and comparative methods. In addition, a meta-analysis of proportion was applied according to the level of difference between the measures. The risk of bias and applicability of the studies were assessed using the QUADAS-2 tool. The certainty of evidence was assessed with the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach. RESULTS: Twenty-nine studies were included in the qualitative analysis and twenty-three in the quantitative analysis. The methods of comparison for the electronic measurement were the radiographic method, radiovisiographic, scanning electron microscopy, and direct visualization. The meta-analysis showed that the electronic measurement tends to be shorter than radiographic measurement, while the other methods showed no difference. The proportion analysis showed a higher pooled proportion of difference values between electronic and comparative measurements within -0.5 to +0.5 mm (69.31%). The certainty of the evidence suggested very low confidence in estimating the outcome. DISCUSSION: The results of this review denote a good performance of the EALs in determining working length in primary teeth pulpectomies. However, these results are based on clinical studies with low methodological quality and high heterogeneity, which require careful interpretation for clinical practice. CONCLUSIONS: Although the results suggest acceptable accuracy of EALs in determining working length in primary teeth pulpectomies, the low quality of the included studies and the very low certainty of the evidence require clinicians to interpret these results with caution. More robust evidence is required to support that these devices are accurate for primary teeth. REGISTRATION: CRD42021277414 (PROSPERO).

Radiographic outcomes and prognostic factors in nonvital immature permanent teeth after apexification with modified calcium hydroxide paste: a retrospective study.

OBJECTIVE: To assess the radiographic outcomes and prognostic factors in nonvital immature permanent teeth after apexification with modified calcium hydroxide paste. MATERIALS AND METHODS: Clinical and radiographic data were collected from 115 necrotic immature permanent teeth (71 caused by trauma and 44 caused by dens evaginatus) treated with apexification using a modified calcium hydroxide. Postoperative root morphology and changes in radiographic root area (RRA) on periapical radiographs were determined and statistically evaluated. Regression analysis was performed to identify factors associated with the outcomes of apexification. RESULTS: The average time for a calcified barrier formation was 10.66 ± 6.37 months. The root morphology after apexification with calcium hydroxide + iodoform paste was similar to that previously described after calcium hydroxide apexification. Compared with the trauma cases, the dens evaginatus cases revealed more type I (40.91% vs 16.9%) and less type II morphology (45.45% vs 67.61%). Although the changes in RRA were limited, the dens evaginatus cases showed greater increment of RRA than the trauma cases (4.12% ± 5.58% vs 0.70% ± 5.21%, P < 0.001). A significant association was found between the preoperative stage of root development and postoperative percentage change in RRA (P < 0.001). CONCLUSIONS: Teeth caused by dens evaginatus had better outcomes after apexification than teeth caused by trauma. Early stages of root development were associated with superior radiographic outcomes. CLINICAL RELEVANCE: Apexification provided reliable outcomes in the treatment of immature teeth with pulp necrosis and apical periodontitis, even though the root development is limited. Treatment decision should be made with comprehensive evaluation of prognostic factors.

Morphological changes of the root apex in anterior teeth with periapical periodontitis: an in-vivo study.

INTRODUCTION: The aim was to analyze the morphological changes of root apex in anterior teeth with periapical periodontitis. METHODS: 32 untreated anterior teeth with periapical periodontitis were enrolled, compared with the healthy contralateral teeth. Two-dimensional measurement of Cone-beam computed tomography was used to determine the location and measure diameter of the apical constriction according to Schell's methods. An open-source software (3D Slicer) was used to reconstruct the teeth. The apical constriction form was analysis according to Schell's topography. The distances of apical constriction to apical foramen and anatomical apex were measured respectively. RESULTS: The difference value between buccolingual and mesiodistal diameter was (0.06 ± 0.09) mm and (0.04 ± 0.04) mm in periapical periodontitis and controls (p < 0.05). The mean distance between apical constriction and anatomical apex was significantly shorter in periapical periodontitis than controls, so was the mean distance of apical constriction to apical foramen. The most common form of apical constriction was flaring (65.6%) in periapical periodontitis. CONCLUSIONS: The anterior teeth with periapical periodontitis had shorter distances of apical constriction to anatomical apex and apical foramen, bigger disparities between the diameters of buccolingual and mesiodistal, and higher proportion of flaring apical constriction.

Age Determination in Children Using Camirere's Indian Specific Formula: A Radiographic Study Using Orthopantomographs.

AIM: Determination of age is a pivotal part of forensic dentistry. Since many dental age determination methods are invasive, Cameriere introduced a radiographic method where age evaluation was carried out using an orthopantomogram (OPG). An adaptation of the same formula was later formulated by Rai et al. for the Indian population. The aim of the study was to assess the age and to dictate the efficiency of the Indian version of Cameriere's formula in the Chennai subpopulation. MATERIALS AND METHODS: This study consisted of radiographs belonging to 50 individuals with an age range of 5-15 years. Radiographs were taken using the OPG and the soft copies obtained were analyzed. The variables such as seven left and right permanent mandibular teeth and the number of teeth with closed apical, and with open apical, ends of roots were examined and measured. The obtained data, after substituting in the formula was statistically analyzed using paired and unpaired t-test and Pearson's correlation coefficient test. RESULTS: On comparing dental age and chronological age, statistically significant results were obtained on both sides of the radiograph. Between genders, both sides of the radiograph showed non-significant results. On correlating the sides, the left side showed greater accuracy in age determination compared to the right side of the OPG. CONCLUSION: Age estimation using Indian-specified formula provides a near good estimate and hence can be a reliable method to measure the chronological age of the participants. CLINICAL SIGNIFICANCE: The Indian version of the Cameriere's formula can be used as a rational tool to assess the age of young children and adolescents.

Radiographic and electronic working length comparison. An in vivo study of three Electronic Apex Locator devices.

The aim of this study is to compare the working length measured with Root ZX (EAL1), Propex II (EAL2) and Endo Analyzer Model 8005 (EAL3) with radiographic measurements during endodontic treatment. Fifty single canal teeth scheduled for endodontic treatment were selected for the study. After endodontic access preparation, pulp chamber was irrigated with 5mL of 5% sodium hypochlorite (NaOCl). The canal was scouted with a size 10 K-file introduced slightly over the apex to verify the canal patency. The working length (WL) was measured using all three EAL devices and radiographically. All measured working lengths were recorded and compared using ANOVA for repeated measures considering the multiple comparison of paired data Least Significant Difference (LSD). The WL mean values for EAL1 were 19.1 ± 1.7 mm; for EAL2 were 19.4 ± 1.7; for EAL3 were 19.4 ± 1.6 and for RG were 19.2 ± 1.7. The Pearson correlation coefficients indicated that the following correlation between electronic devices and radiographic WL: EAL1- 0.986, EAL2- 0.953 and EAL3- 0.931. Considering the mean values compared to radiographic measures, Root ZX gave better results than the other tested EAL devices. Endo Analyzer Model 8005 showed the worst performance.

A laboratory study of the accuracy of three electronic apex locators: influence of embedding media and radiographic assessment of the electronic apical limit.

AIM: To evaluate several factors that might interfere with the use of electronic root canal length measurement devices (ERCLMDs) in a laboratory setting, including two different embedding media (alginate and electroconductive gel), three different types of devices and the radiographic view on the assessment of the electronic readings. METHODOLOGY: Thirty single-rooted extracted human mandibular premolars were selected. After access and canal pre-flaring, a size 10 K-file was inserted in the canal up to the major apical foramen under magnification (×10), and this length was recorded as the actual length (AL) of the canal. Teeth were mounted on a specific endodontic training kit platform (ProTrain). Two different embedding media (electroconductive gel and alginate) and three different ERCLMDs: Apex ID (SybronEndo, Glendora, CA, USA), CanalPro Apex Locator (Coltene-Endo, Cuyahoga Falls, OH, USA) and the Root ZX II (J. Morita, Tokyo, Japan), were tested. Following the measurement at the 0.5 mark of each ERCLMD using alginate, two periapical radiographs (bucco-lingual and proximal views) were taken. The difference between the electronic readings and the AL, as well as the distance from the file tip to the apex of the roots on the radiographs, was calculated. Data were analysed statistically (two-way anova, Tukey's and chi-squared tests) at 5% significance level. RESULTS: The incidence of over-extended readings was significantly greater (P < 0.05) when using the ProTrain electroconductive gel, except for Root ZX II at the 0.5 mark. Root ZX, CanalPro and Apex ID had similar accuracy when the 0.0/APEX mark was used to locate the foramen. For the radiographic method, no difference was found between the devices or radiographic views. CONCLUSION: Compared with alginate, the conductive gel of the ProTrain kit negatively affected most of the electronic readings. The three evaluated ERCLMDs had similar accuracy in locating the apical foramen when using the mark 0.0/APEX and alginate as the embedding media. Although the ProTrain platform allows radiographs to be exposed in both bucco-lingual and proximal views, no difference was found between the views when evaluating the apical limit provided by the 0.5 mark in mandibular premolars embedded in alginate.

Is canal overinstrumentation able to produce apical root dentinal microcracks in extracted teeth?

AIM: To assess the impact of mechanical overinstrumentation of root canals in extracted teeth on the development of dentinal microcracks in the apical portion of the root by means of micro-computed tomographic (micro-CT) analysis. Root canal preparation short of the canal terminus and at the apical foramen (AF) were used as controls. METHODOLOGY: Twenty 2-rooted maxillary premolars with two canals were selected, scanned in a micro-CT device and the root canals prepared sequentially using Reciproc M-Wire R25 instruments to working lengths: 1 mm short of the AF (AF - 1 mm), at the AF (AF), and overinstrumentation (AF + 1 mm). A micro-CT scan of each specimen was performed after each time point. After reconstruction and co-registration procedures, the images were screened from the cementoenamel junction to the apex (n = 55 352) to identify the presence of dentinal microcracks in the apical third of the root. RESULTS: After the analyses of 55 352 slices, dentinal microcracks were visualized in 12.45% of the images (6892 slices), with 5.73% (3174 slices) in the cervical, 3.57% (1976 slices) in the middle and 3.15% (1740 slices) in the apical third. All dentinal microcracks observed at all time points (AF - 1 mm, AF and AF + 1 mm) were already present in the corresponding images before canal instrumentation. Therefore, no new microcracks were detected, regardless of the working length used for canal instrumentation. CONCLUSION: Reciprocating root canal preparation either short, at or beyond the AF (overinstrumentation) did not create dentinal microcracks in the roots of extracted 2-rooted maxillary premolars.