The objectives of this article are to report 2 cases of nonsurgical endodontic treatment for the management of periapical lesions associated with large cortical bone perforations and review the literature on the clinical efficacy of nonsurgical endodontic treatment to draw insights from published case reports. Large, cyst-like periapical lesions in 2 patients were successfully treated with combined modalities of root canal treatment, antimicrobial therapy (calcium hydroxide and triple antibiotic paste [TAP]), and mineral trioxide aggregate (MTA) obturation of the canal space. In both cases, instrumentation was extended 1 mm beyond the apical foramen to facilitate drainage through the root canal, because it was assumed that the periapical lesion could be cystic. After instrumentation, TAP was placed within the canal space to aid in disinfection and healing of the dental, pulpal, and periapical conditions. In both patients, the teeth were asymptomatic and functional at follow-up examinations (case 1, 3 years; case 2, 30 months). Supporting the positive outcomes in the 2 clinical cases, the published literature suggests that the use of biocompatible materials such as MTA, which can promote the deposition of hydroxyapatite, has the potential to contribute to tissue regeneration and the healing of large periapical lesions.

OBJECTIVE: The study aimed to investigate the sinus membrane thickness (SMT) adjacent to healthy endodontically-treated maxillary molars with or without protruded apical foramen into the sinus cavity using cone-beam computed tomography (CBCT).
METHODS: Images of 207 non-smoker patients aged 18-40 were retrospectively analyzed, 140 were endodontically treated, and 136 were without endodontic treatment. Patients with any sinus pathology, teeth that have symptoms, or poor root filling were excluded. Study groups consisted of Group EM-I (endodontically treated and protruded apical foramen), Group EM-C (endodontically treated and contacted apical foramen), and similarly without endodontic treatment; Group M-I and Group M-C. SMT upon the mesial, distal, and palatal roots was measured. One-way ANOVA and Student\'s t-tests were performed.
RESULTS: Group EM-I had the thickest sinus membrane compared to other groups (p = 0.013). SMT values were 2.37-2.60 mm in Group EM-I, and 1.34-1.58 mm in other groups. Thickening (> 2 mm) percentages were 33.45% in Group EM-I and between 4.25 and 8.25% in other groups. No statistical difference was detected between first and second molars and genders (p > 0.05).
CONCLUSIONS: When the apical foramen protruded into the sinus cavity, the conventional root canal treatment caused a minimal (between 2.37 mm and 2.60 mm) sinus membrane thickening with a rate of 33.45% based upon CBCT examinations.

BACKGROUND: Traditionally, radiographs were used to assess the working length of root canals. However, the use of Electronic Apex Locators (EAL) may be a non-invasive alternative. This study aimed to evaluate the accuracy of the electronic apex locator (EAL) compared to radiographic measurements in determining the working length of root canals.
METHODS: The study assessed the performance of EALs in different scenarios, including the presence of blood and pulp tissue, the use of ethylenediaminetetraacetic acid (EDTA), sodium hypochlorite (NaOCl) as an irrigant, and post-instrumentation with normal saline. An electronic apex locator (DTE DPEX-V; Woodpecker, China) was used alongside traditional radiographs to measure the working length in 144 root canal treatments. Bland-Altman analysis was used to compare the measurements between EAL and radiographs using Jamovi software, v2.4.8 (https://www.jamovi.org/).
RESULTS: The findings revealed strong correlations between EAL and radiographic measurements across all testing environments, with Pearson\'s correlation coefficients ranging from 0.944 to 0.998. The Bland-Altman analysis suggests bias; the average difference was negative and close to zero (Pulp: -0.354, EDTA: -0.0972, NaOCl: -0.0382, Saline: -0.0139) when EAL measurements were compared to radiographic measurements.
CONCLUSIONS: The working length measurement of root canals using an electronic apex locator such as DTE DPEX-V is comparable to traditional radiographic measurements. The use of irrigants improves the measurement. The EAL has the potential to be an alternative to the invasive radiograph for root canal length measurement.

The study evaluated the spatial position of the mental foramen (MF) using 300 cone-beam computed tomography. The spatial position was analyzed with the horizontal location and relative location (distance between apical foramen and MF). The horizontal location was assessed through three positions (positions 1, 2, and 3). The relative location was determined with the x, y, and x coordinates of the root apex of mandibular premolars and the MF. Student\'s t-test and chi-square were performed. The most common horizontal location (52%) was position 2, which means between the premolars (p < 0.05). The relative location of the MF to the root apex of the second premolar was closer than the first premolar (p < 0.05). The distance between the root tip of the second premolar and the MF was 5.27 mm, with a minimum value of 1.87 mm. Clinicians should be aware of the possible neural results to the mental nerve of an endodontic infection and the extrusion of irrigation solutions.

BACKGROUND: This ex vivo study evaluated the accuracy of the Electronic Apex Locator (EAL) and Automatic Apical Stop (AAS) functions of the E-Connect S+ and Morita Tri Auto ZX2+ cordless apex locators in determining patency length.
METHODS: Sixty-four human teeth with a single root were randomly allocated into E-connect or Morita groups (n = 32). The canals were accessed and preflared, after which a size 15 K-file was inserted into the canal to the major foramen and recorded as the actual length (AL). Matched measurements were taken using the AAS and EAL functions and visually confirmed with confocal microscopy. The variance between canal length (mm), the persons correlation (ρ) between function and AL, and the accuracy (%) of the canal length relative to the AL (Δmm) between devices and functions were assessed.
RESULTS: Regardless of device or function, all measurements were within 1±Δmm and correlated strongly (ρ > 0.97) with the AL. When considering a more stringent clinically acceptable range of 0.5±Δmm from the AL, all devices and functions demonstrated similar accuracy levels (84%-94%). However, at lower tolerance ranges, the E-connect device with the EAL function exhibited the highest accuracy. On average, all devices and functions stopped short of the AL (mean Δmm>0).
CONCLUSIONS: The E-Connect S+ and Morita Tri Auto ZX2+ apex locators provided reliable accuracy in determining the position of the major foramen. These findings demonstrate a high level of reproducibility in canal length measurements using both cordless endodontic handpieces, regardless of whether the EAL or AAS functions were employed.

UNASSIGNED: Electronic apex locators (EALs) are frequently used as adjuvant to radiographs in working length (WL) determination. The introduction of integrated apex locators (IALs) further simplified the root canal treatment by continuous monitoring of the apex while root canal shaping.
UNASSIGNED: The aim of this study was to evaluate the efficacy of radiographs, EAL, and IAL in determining the WL in the presence of various irrigants.
UNASSIGNED: The present in vivo study was carried out on 30 patients who were divided into 10 in each group, based on the type of irrigant used; 0.9% saline (Group 1), 0.2% chlorhexidine (Group 2), and 2.5% of sodium hypochlorite (NaOCL) (Group 3). In each group, WL is determined using conventional radiographs, Root ZX Mini (EAL), and CanalPro CL2i (IAL).
UNASSIGNED: Kruskal-Wallis test and Friedman\'s two-way ANOVA test were used for statistical analysis.
UNASSIGNED: Mean WL was comparably lower with Root ZX Mini, while the WL by CanalPro CL2i and the radiographic method were comparable. In all methods, the type of solutions used did not influence the WL, with a higher mean WL when NaOCL is used as an irrigant. Nevertheless, the above comparisons were not statistically significant.
UNASSIGNED: the irrigation solutions employed in this study had no impact on the performance of apex locators and radiographs.

暂无摘要。

To investigate the CBCT findings of the apical anatomy of immature maxillary central incisors.
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.
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.
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.
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.

The apex area in the primary teeth changes continuously due to the physiologic resorption, therefore; the apical foramen (AF) may not correspond to the anatomic apex (AA), which gives a big challenge to achieve successful endodontic treatment. The aim of this research was to study the difference distance (DD) between the position of the AA and AF, besides the difference acceptance (DA) in primary teeth, and the effect of the following variables: root canal curvature, resorption degree, and canal size on DD and DA separately.
In this research, 180 root canals from 60 primary teeth were studied. Two lengths of each canal were measured by a K-file from a certain point in the crown; the first length was until the AA and the second was until the AF. Then DD was obtained by calculating the difference between those two lengths. Statistical analysis tests were done. A p value of <.05 was considered significant at a 95% confidence level.
The percentage of canals with 0 mm DD was 34.4%, while it was 1.1% with DD of 6 mm. The percentages of acceptable ( ≤ 2 mm) and unacceptable ( > 2 mm) difference were 84.4% and 15.6%, respectively. There was a significant difference in the DD value between the three groups of curvature degree and the three groups of canal size. There was a significant difference between the DA in the three groups of canal size.
DD has a wide variation value in primary teeth regardless of the degree of root resorption, which has not affected this value or the accepted difference; however, DD and acceptable difference values are somehow affected by the degree of root curvature and canal size. We recommend adding acceptable difference as a criterion when considering pulpectomy treatment in primary teeth.

To determine the efficacy of endodontic microsurgery for teeth with an undeveloped root apex and periapical periodontitis caused by an abnormal central cusp fracture after failed nonsurgical treatment.
Eighty teeth in 78 patients were subjected to endodontic microsurgery. All patients were clinically and radiologically examined 1 year postoperatively. The data were statistically analyzed using SPSS 27.0 software.
Of the 80 teeth in 78 patients, periapical lesions had disappeared in 77 teeth at 1-year postoperative follow-up, with a success rate of approximately 96.3% (77/80). The efficacy of endodontic microsurgery was not affected by sex, age, extent of periapical lesions, and presence of the sinus tract. Between-group differences were not statistically significant (P > 0.05).
Endodontic microsurgery can be an effective alternative treatment option for teeth with an undeveloped root apex and periapical periodontitis caused by an abnormal central cusp fracture after nonsurgical treatment failure.