Length Measurements Research Articles

Lipopolysaccharide with long O-antigen is crucial for Salmonella Enteritidis to evade complement activity and to facilitate bacterial survival in vivo in the Galleria mellonella infection model.

Bacterial resistance to serum is a key virulence factor for the development of systemic infections. The amount of lipopolysaccharide (LPS) and the O-antigen chain length distribution on the outer membrane, predispose Salmonella to escape complement-mediated killing. In Salmonella enterica serovar Enteritidis (S. Enteritidis) a modal distribution of the LPS O-antigen length can be observed. It is characterized by the presence of distinct fractions: low molecular weight LPS, long LPS and very long LPS. In the present work, we investigated the effect of the O-antigen modal length composition of LPS molecules on the surface of S. Enteritidis cells on its ability to evade host complement responses. Therefore, we examined systematically, by using specific deletion mutants, roles of different O-antigen fractions in complement evasion. We developed a method to analyze the average LPS lengths and investigated the interaction of the bacteria and isolated LPS molecules with complement components. Additionally, we assessed the aspect of LPS O-antigen chain length distribution in S. Enteritidis virulence in vivo in the Galleria mellonella infection model. The obtained results of the measurements of the average LPS length confirmed that the method is suitable for measuring the average LPS length in bacterial cells as well as isolated LPS molecules and allows the comparison between strains. In contrast to earlier studies we have used much more precise methodology to assess the LPS molecules average length and modal distribution, also conducted more subtle analysis of complement system activation by lipopolysaccharides of various molecular mass. Data obtained in the complement activation assays clearly demonstrated that S. Enteritidis bacteria require LPS with long O-antigen to resist the complement system and to survive in the G. mellonella infection model.

Transcription Decisions of Conjoined Independent Clauses Are Equitable Across Dialects but Impact Measurement Outcomes.

Transcription of conjoined independent clauses within language samples varies across professionals. Some transcribe these clauses as two separate utterances, whereas others conjoin them within a single utterance. As an inquiry into equitable practice, we examined rates of conjoined independent clauses produced by children and the impact of separating these clauses within utterances on measures of mean length of utterance (MLU) by a child's English dialect, clinical status, and age. The data were archival and included 246 language samples from children classified by their dialect (African American English or Southern White English) and clinical status (developmental language disorder [DLD] or typically developing [TD]), with those in the TD group further classified by their age (4 years [TD4] or 6 years [TD6]). Rates of conjoined independent clauses and the impact of these clauses on MLU varied by clinical status (DLD < TD) and age (TD4 < TD6), but not by dialect. Correlations between the rate of conjoined clauses, MLU, and language test scores were also similar across the two dialects. Transcription decisions regarding conjoined independent clauses within language samples lead to equitable measurement outcomes across dialects of English. Nevertheless, transcribing conjoined independent clauses as two separate utterances reduces one's ability to detect syntactic differences between children with and without DLD and document syntactic growth as children age. https://doi.org/10.23641/asha.25822675.

Suitability of multifunction devices Myah and Myopia Master for monitoring myopia progression in children and adults.

To assess the feasibility of using multifunction instruments to measure axial length for monitoring myopia progression in children and adults. Axial length was measured in 60 children (aged 6-18 years) and 60 adults (aged 19-50 years) with multifunction instruments (Myah and Myopia Master) and stand-alone biometers (Lenstar LS900 and IOLMaster 700). Repeatability (measurements by the same examiner) and reproducibility (measurements by different examiners) were computed as the within-subject standard deviation (Sw) and 95% limits of agreement (LoA). Inter-instrument agreement was computed as intraclass correlation coefficients. The threshold for detecting myopic progression was taken as 0.1 mm. Measures were repeated only in children following the administration of 1% tropicamide to determine the impact of cycloplegia on axial length. Overall, the IOLMaster 700 had the best repeatability in children (0.014 mm) and adults (0.009 mm). Repeatability Sw values for all devices ranged from 0.005 to 0.021 mm (children) and 0.003 to 0.016 mm (adults). In children, reproducibility fell within 0.1 mm 95% of the time for the Myah, Myopia Master and IOLMaster 700. Agreement among all devices was classified as excellent (ICC 0.999; 95% CI 0.998-0.999), but the 95% LoA among the Myah, Myopia Master and Lenstar LS900 was ≥0.1 mm. Cycloplegia had no statistically significant effect on axial length (all p > 0.13). The Myah and Myopia Master multifunction instruments demonstrated good repeatability and reproducibility, and their accuracy was comparable to stand-alone biometers. Axial length measurements using different instruments can be considered interchangeable but should be compared with some caution. Accurate axial length measurements can be obtained without cycloplegia. The multifunction instruments Myah and Myopia Master are as well suited for monitoring myopia progression in children asthe stand-alone biometers IOLMaster 700 and Lenstar LS900.

Prevention of malnutrition after one anastomosis gastric bypass: value of the common channel limb length.

Hypoalbuminemia and anemia are commonly observed indications for one anastomosis gastric bypass (OAGB) reversal and remain significant concerns following the procedure. Sufficient common channel limb length (CCLL) is crucial to minimize nutritional complications. However, limited literature exists regarding the impact of CCLL on OAGB outcomes. This study aimed to assess the effect of CCLL on weight loss and nutritional status in patients who underwent OAGB. A prospective cohort study was conducted from August 2021 to July 2022, involving 64 patients with a body mass index of 40-50kg/m2. The standardized length of the biliopancreatic limb (BPLL) for all patients in this study was set at 175cm. Additionally, the measurement of the common channel limb length (CCLL) was performed consistently by the same surgeon for all included patients. The mean age and BMI of the patients were 39.91 ± 10.03 years and 43.13 ± 2.43kg/m2, respectively, at the time of surgery. There was a statistically significant negative correlation between CCLL and percent total weight loss (%TWL) at the 12-month mark after OAGB (P = 0.02). Hypoalbuminemia was observed in one patient (1.6%), while anemia was present in 17 patients (26.6%) at the one-year follow-up. Statistical analysis revealed no significant difference in the incidence of anemia and hypoalbuminemia between patients with CCLL < 4m and those with CCLL ≥ 4m. A CCLL of 4m does not appear to completely prevent nutritional complications following OAGB. However, maintaining a CCLL of at least 4m may be associated with a reduced risk of postoperative nutritional deficiencies.

Sensitivity of the Modified Exponentially Weighted Moving Average Sign-Rank Control Chart to Process Changes in Counted Data

Control charts are generally used to detect mean process changes in continuous processes. However, counting procedures that characterize product quality are popular in production processes, such as the number of defects or the proportion of defective products. This research aims to investigate using the Modified Exponentially Weighted Moving Average combined with a nonparametric Sign Rank control chart, namely MEWMA-SR chart is a novel tool. Comparative analyses involving different run length measures are conducted to evaluate the proposed scheme against MEWMA, MEWMA-SR, and classical EWMA charts. The performance of the MEWMA-SR chart is assessed using Monte Carlo simulations based on its run-length profiles. It was found that the proposed combination control chart was effective in detecting changes better than other control charts along with presenting applications with real data. A study further validates the proposed chart’s practical utility through a case study analyzing COVID-19 mortality data.

Automated body length and body condition measurements of whales from drone videos for rapid assessment of population health

AbstractMonitoring body length and body condition of individuals helps determine overall population health and assess adaptation to environmental changes. Aerial photogrammetry from drone‐based videos is a valuable method for obtaining body length and body condition measurements of cetaceans. However, the laborious manual processing of drone‐based videos to select frames to measure animals ultimately delays assessment of population health and hinders conservation actions. Here, we apply deep learning methods to expedite the processing of drone‐based videos to improve efficiency of obtaining important morphological measurements of whales. We develop two user‐friendly models to automatically (1) detect and output frames containing whales from drone‐based videos (“DeteX”) and (2) extract body length and body condition measurements from input frames (“XtraX”). We use drone‐based videos of gray whales to compare manual versus automated measurements (n = 86). Our results show automated methods reduced processing times by one‐ninth, while achieving similar accuracy as manual measurements (mean coefficient of variation &lt;5%). We also demonstrate how these methods are adaptable to other species and identify remaining challenges to help further improve automated measurements in the future. Importantly, these tools greatly speed up obtaining key morphological data while maintaining accuracy, which is critical for effectively monitoring population health.

Exploring anthropometric and functional factors that influence working adult's handgrip strength in north Australia.

Handgrip strength (HGS) is a reliable assessment of hand function. Interpretation of HGS is commonly done using normative data. Normative HGS data HGS considers the influence of age and gender without adjustment for anthropometric measurements or functional factors known to influence HGS. To determine the potential relationship of select anthropometric measurements (height, weight, hand length and width, forearm length and circumference) and functional factors (hand dominance, work and lifestyle category) to HGS. This study included a sample of 119 males and 96 female workers from North Queensland. HGS and six anthropometric measurements were obtained using calibrated instruments and reliable measurement protocols. Age and gender along with three functional factors were documented by self-report. Right and left mean HGS was greater for individuals who performed heavy/very heavy work (58.1±10.1 kg and 54.1±10.9 kg respectively) compared to light (38.5±12.3 kg and 35.5±11.8 kg) or medium work (44.1±10.8 kg and 40.0±12.9 kg). Mean HGS was greater for individuals who performed heavy/very heavy activity (right 48.5±13.6 kg and left 44.5±13.7 kg) compared to light activity (right 36.3±11.2 kg and left 33.9±11.3 kg) within their lifestyle. HGS positively correlated with gender (p = 0.0001), work (p = 0.001) and anthropometric measurements of forearm circumference (p = 0.001), hand length (p = 0.006) and hand width (p = 0.052). Easy to measure anthropometric measurements of forearm circumference, hand length and width are the strongest predictors of HGS in addition to an individual's physical activity at work and in their lifestyle. Consideration of these factors could lead to improved evaluation of HGS scores.

Thermally compensated common-path differential interferometer with reduced long-term zero-drifts

Abstract Laser interferometers have served as the workhorses in the metrology of length for several decades. Their broader application brings further challenges, especially for longer measurement time-frames or outside the laboratory environment with strictly controlled conditions. As a part of our team's activities aiming at characterizing and eliminating the effects of unstable temperature on interferometric length measurements, we report on successfully remodelling a differential interferometer's optical arrangement focused on increasing resilience against temperature changes. The experimental characterization under constant temperature and subsequently under thermal load proved a tenfold decrease in short-term fluctuations and reduced sensitivity to temperature changes by a factor of 100.

Exploratory investigation of virtual lesions in gastrointestinal endoscopy using a novel phase‐shift method for three‐dimensional shape measurement

AbstractAccurate measurement of the size of lesions or distances between any two points during endoscopic examination of the gastrointestinal tract is difficult owing to the fisheye lens used in endoscopy. To overcome this issue, we developed a phase‐shift method to measure three‐dimensional (3D) data on a curved surface, which we present herein. Our system allows the creation of 3D shapes on a curved surface by the phase‐shift method using a stripe pattern projected from a small projecting device to an object. For evaluation, 88 measurement points were inserted in porcine stomach tissue, attached to a half‐pipe jig, with an inner radius of 21 mm. The accuracy and precision of the measurement data for our shape measurement system were compared with the data obtained using an Olympus STM6 measurement microscope. The accuracy of the path length of a simulated protruded lesion was evaluated using a plaster model of the curved stomach and graph paper. The difference in height measures between the measurement microscope and measurement system data was 0.24 mm for the 88 measurement points on the curved surface of the porcine stomach. The error in the path length measurement for a lesion on an underlying curved surface was &lt;1% for a 10‐mm lesion. The software was developed for the automated calculation of the major and minor diameters of each lesion. The accuracy of our measurement system could improve the accuracy of determining the size of lesions, whether protruded or depressed, regardless of the curvature of the underlying surface.

Management, Utilization, and Outcomes of Preterm Labor in an Integrated Health Care System.

Fetal fibronectin (fFN) testing and transvaginal ultrasound (TVUS) are diagnostic tools used to predict impending spontaneous preterm birth (sPTB) among women presenting with preterm labor (PTL). We evaluated the association between fFN testing or TVUS cervical length (CL) measurement in predicting sPTB, respiratory distress syndrome (RDS), neonatal intensive care unit (NICU) admission, and sPTB-related costs. We conducted a retrospective cohort study using data from the Kaiser Permanente Southern California electronic health system (January 1, 2009-December 31, 2020) using diagnostic and procedure codes, along with a natural language processing algorithm to identify pregnancies with PTL evaluations. PTL evaluation was defined as having fFN and/or TVUS assessment. Outcomes were ascertained using diagnostic, procedural, and diagnosis-related group codes. Multivariable logistic regression assessed the association between fFN and/or TVUS results and perinatal outcomes. Compared with those without PTL evaluations, those with positive fFN tests had higher adjusted odds ratio (adj.OR) for sPTB (2.95, 95% confidence interval [CI]: 2.64, 3.29), RDS (2.34, 95% CI: 2.03, 2.69), and NICU admission (2.24, 95% CI: 2.01, 2.50). In contrast, those who tested negative had lower odds for sPTB (adj.OR: 0.75, 95% CI: 0.70, 0.79), RDS (adj.OR: 0.67, 95% CI: 0.61, 0.73), and NICU admission (adj.OR: 0.74, 95% CI: 0.70, 0.79). Among those with positive fFN results, the odds of sPTB was inversely associated with CL. Health care costs for mothers and neonates were lowest for those with fFN testing only. This study demonstrates that positive fFN results were associated with an increased odds of sPTB, RDS, and NICU admission and the association with sPTB was inversely proportional to CL. Additionally, negative fFN results were associated with decreased odds of sPTB, RDS, and NICU admissions. fFN testing may predict these and other sPTB-related adverse outcomes hence its utility should be explored further. Moreover, fFN testing has some cost savings over TVUS. · Patients with positive fFN tests had higher odds of sPTB, RDS, and NICU admission.. · Inverse relationship between sPTB and CL among those with positive fFN tests was observed.. · Health care costs for mothers and neonates were lowest for those with fFN testing only..

Zygomatic Implant Length Measurement Without Excessive Flap Release: A Human Cadaver Study.

One of the most important steps in zygomatic implant surgery is to determine the implant length. This cadaver study aims to identify an alternative technique for determining the length of the implant in zygoma surgery without excessive elevation of the flap. A total of 30 cadavers were included in this study. Measurements were made with a probe by seeing the exit point of the drills from the lateral aspect of the zygomatic bone. Secondly, without excessive flap release, the distance that the depth probe first raises the skin over the lateral border of the zygoma is measured. The average difference between the measurements made without excessive elevation of the flap and with a retractor placed on the zygomaticofrontal notch was found to be 5.41 ± 0.94mm (range: 5-7.5mm). According to the results of this study, the zygomatic implant should be placed at least 5 mm shorter than the length at which the depth probe first raises the skin over the lateral border of the zygomatic bone.

Clinical Study of a Four-Step Program for the Treatment of Plantar Fasciitis with Bone Spurs.

The most common causes of plantar and heel pain are plantar fasciitis and calcaneal spurs, and they often co-exist. Surgery is a recognized treatment for refractory plantar fasciitis. However, few studies have proposed treatment options for patients with metatarsophalangeal fasciitis with bone spurs. Accordingly, this study's purpose was to propose a four-step surgical regimen, and to improve the surgical outcome of plantar fasciitis with osteophytes and to establish a procedure for surgical treatment. Retrospective analysis of 45 patients suffering from plantar fasciitis with bone spurs from 2020 to 2023. All patients underwent a four-step procedure, including plantar fascia release, calcaneal spur grinding, inflammatory tissue removal, and calcaneal burr decompression. The imaging parameters and functional scores were recorded before and after the operation. The objective evaluation included the measurement of calcaneal spur length on radiographs. Clinical evaluation included the American Orthopaedic Foot and Ankle Society (AOFAS), the Visual Analog Scale (VAS), and the Foot and Ankle Outcome Scale (FAOS). Measurement data that conformed to normal distribution were expressed as (x2 ± s), and pre-and postoperative AOFAS, FAOS, and VAS scores were compared using repeated-measures ANOVA, and preoperative and postoperative spur lengths were compared using paired t-tests. The 45 patients were followed up for 3 to 30 months, (17.72 ± 8.53) months, at final follow-up, the patient's AOFAS score improved from preoperative (74.93 ± 5.56) to (94.78 ± 3.98), FAOS score increased from preoperative (76.42 ± 3.37) to (96.16 ± 2.74), the VAS score decreased from (3.18 ± 0.54) to (1.07 ± 1.20) (p < 0.05), the length of spur decreased from (0.72 ± 1.81) cm to (0.23 ± 1.19) cm, and there were significant differences before and after operation (p < 0.05). The four-step surgical regimen is an appropriate and effective surgical procedure to treat plantar fasciitis with bone spurs.

Myopia prevalence and ocular biometry in children and adolescents at different altitudes: a cross-sectional study in Chongqing and Tibet, China

ObjectiveTo investigate the differences in myopia prevalence and ocular biometry in children and adolescents in Chongqing and Tibet, China.DesignCross-sectional study.SettingThe study included children and adolescents aged 6–18 years in Chongqing,...

2D/4D Finger Length Ratio in the Screening of Developmental Dysplasia of the Hip.

To investigate whether there is a relationship between the 2nd finger and 4th finger length measurement ratios and developmental dysplasia of the Hip (DDH). Cross-sectional observational study. Place and Duration of the Study:Department of Orthopaedics and Traumatology, Meram Faculty of Medicine Hospital, Konya, Turkiye, from January 2020 to May 2023. Infants were screened for DDH with Graff method for the ultrasounds of both hips. Lengths of the 2nd and 4th fingers of both hands were measured and recorded. Patients with additional risk factors for developmental dysplasia of the hip (breech birth, family history, oligohydramnios, swaddling) were excluded. Two hundred and fifty-six babies were screened including 55.1% (n = 141) girls and 44.9% (n = 115) boys. Their mean age was 2.51 ± 0.80 months. The average lengths were 31.73 ± 3.05 mm, for the left 2nd finger and 34.26 ± 3.48 mm for the left 4th finger. In the hip USG measurements, the mean alpha angles were 62.91 ± 3.12° for the right hip and, 63.20 ± 3.55° for the left hip. Eighteen (7%) of babies who underwent hip ultrasound (USG) had unilateral or bilateral DDH. Among these cases, 2.7% (n = 7) had right, 2.3% (n = 6) had left, and 2% (n = 5) had bilateral DDH. There was no statistically significant correlation between the ratios of right 2/4 finger lengths and the right alpha angle (rs = 0.051; p = 0.421). There was a statistically positive and statistically significant correlation between the ratios of left 2/4 finger lengths and the left alpha angle (rs = 0.154; p = 0.013). Only the left-hand finger ratio among the parameters in the model had a statistically significant effect on DDH. Therefore, the left hand 2D/4D finger length may be of value in screening for DDH. Developmental dysplasia of the hip, Second to fourth finger digit ratio, Ring finger, Digit ratios.

Morphology and morphometry of morphotypes in the population of Artemia franciscana (Kellogg, 1906) from salterns of the southeastern coast of India.

We document the morphology, morphometric variations among the morphotypes of the brine shrimp, Artemia franciscana. From the samples collected at four different locations in South India, Tamil Nadu viz. Kelambakkam, Vedaranyam, Tuticorin and Nagarcoil we identified six morphotypes: M1, M3, M4 in males and F1, F2, F3 in females. The Scanning electron micrographs of male morphotypes show distinct variation in the basal width, shape and number of cuticular cones on the second antennae. Similarly, the female morphotypes show various shape and sizes of the ovisac with or without spines. However, the cyst surface topography is smooth without any specific variation/ornamentation in all three female morphotypes. Multivariate analysis of eighteen morphological traits measured in males and fifteen in females to elucidate the intraspecific variations among morphotypes indicate significant dissimilarity between males and females. Furthermore, relative length measurements showed distinct morphometric variation of traits between the morphotypes encountered at different sampling sites.

Vein Pattern Visualisation for Biometric Identification with cGAN on a New Zealand Dataset

Forensic identification using vein patterns in standard colour images presents significant challenges due to their low visibility. Recent efforts have employed various computational techniques, including artificial neural networks and optical vein disclosure, to enhance vein pattern detection. However, these methods still face limitations in reliability when compared to Near-Infrared (NIR) reference images. One of the biggest challenges of the studies is the limited number of available datasets that have synchronised colour and NIR images from body limbs. This paper introduces a new dataset comprising 602 pairs of synchronised NIR and RGB forearm images from a diverse population, ethically approved and collected in Auckland, New Zealand. Using this dataset, we also propose a conditional Generative Adversarial Networks (cGANs) model to translate RGB images into their NIR equivalents. Our evaluations focus on matching accuracy, vein length measurements, and contrast quality, demonstrating that the translated vein patterns closely resemble their NIR counterparts. This advancement offers promising implications for forensic identification techniques.

Canine sexual dimorphism in crown and root dimensions: a cone-beam computed tomographic study.

The primary step in forensic odontological analysis is sex determination. The present study is one of the few studies that evaluated the accuracy of the combination of canine tooth root length and crown measurements for sex determination. The study sample comprised 196 cone-be am computed tomographic scans of individuals aged 20-80 years distributed in five age categories: 20-29, 30-39, 40-49, 50-59, and 60+ years old. Different parameters, such as width, length, and ratio measurements for the crown and root of each maxillary and mandibular canine tooth, were examined and recorded. The findings indicated that maxillary canines had greater sex dimorphism ability (87.3%) than mandibular canines (80.6%). Total tooth length and root length of maxillary canine were the most pronounced variables in the differentiation of sex groups. When the combination of the mandibular and maxillary measurements was considered, the accuracy for sex dimorphism was 85.7%. By using ratio variables, the accuracy was reduced to 68.9%. According to the findings of this study, total tooth length and root length are the most discriminant variables of canine teeth. These variables are more reliable sex indicators than crown measurements.

Features of the biological development of schoolchildren in the Moscow region with different levels of health.

BACKGROUND. The study of the health status of the younger generation, and the dynamics of the schoolchildren physical and biological development remains an urgent scientific problem both in our country and around the world. Changes in the lifestyle of modern children and adolescents require regular revision and updating of regional standards for physical and biological development. AIM. Analysis of the dynamics of puberty in modern schoolchildren depending on their health status, with subsequent updating of schoolchildren biological development standards in the Moscow region. MATERIALS AND METHODS. In the 2020s, an observational single-center cross-sectional sample study of the schoolchildren health status, physical and biological development in the Moscow region aged 12-16 years was carried out. Assessment of physical and biological development was conducted in each age and sex group according to standard methods using certified anthropometric instruments with measurements of body length and weight. RESULTS: The study involved 508 schoolchildren with different levels of health: first health group – 107 (21.1%), second – 208 (58.7%), third – 103 (20.2%). Among the functional abnormalities in the study sample, the leading ones were diseases of the eye and its adnexal apparatus (24%), and in the structure of chronic diseases, diseases of the musculoskeletal system and connective tissue (20%). The level of biological development in schoolchildren assigned to the first and to the second health groups in comparison with schoolchildren from the third health group did not differ significantly (p 0.05), however, there was a tendency towards to a later development of secondary sexual characteristics in schoolchildren with chronic diseases. Significant (p=0.038) differences in the age at menarche in girls were found depending on the level of physical development. The data indicate that when developing standards for biological development, it is necessary to take into account the data of only schoolchildren who have 1 and 2 health groups. CONCLUSIONS: The results of this study clearly demonstrated the prevalence of functional abnormalities and chronic diseases of various nosologies among modern schoolchildren in the Moscow region. The results of the study formed the basis of updated standards for the schoolchildren biological development in the Moscow region.

Measurement method for live chicken shank length based on improved ResNet and fused multi-source information

Phenotypic parameters are crucial reference indicators in poultry breeding. However, the chickens shank length is still manually measured, which is time-consuming and labor-intensive. Additionally, the measurement results are difficult to unify due to the subjective factors of different individuals. To address this issue, this paper proposed a method for live chicken shank length measurement (SLM). It enriches chicken shank feature by fusing visible images and infrared images. The fusion images are then input into a deep regression model based on the improved ResNet. The measurement model used ResNet as its backbone and introduces Squeeze-and-Excitation (SE) blocks and a Spatial Pyramid Pooling (SPP) block, resulting in more precise and stable shank length measurements. The average coefficient of variation, average floating error, average standard deviation and Pearson correlation coefficient for shank length measurements using the fusion images are 0.21 %, 0.49 %, 0.181 mm and 0.996, respectively, compared with using single visible or infrared image, the accuracy and stability are obviously improved. That indicated combining deep learning model and fusion information, the SLM proposed in this paper can achieve a more precise, reliable and standardized measurement of live chicken shank length.

Knowledge, attitude, and practice of endodontists for use of apex locators in clinical practice in India: A survey-based study

ABSTRACT Aim: The present study aimed to evaluate the knowledge, attitude, and practice (KAP) of endodontists in India for working length measurements using Apex locators. Materials and Methods: This study is an online questionnaire-based survey consisting of 24 questions in total, divided into five parts. The first part consisted of questions related to demographic details, the second part inquires about the tools and technology used for working length determination, and the remaining questions evaluate the KAP regarding the use of apex locators to determine working length (five questions each). Participants in the study were either pursuing or completed postgraduation in endodontics. A total of 257 responses were recorded; however, six participants were excluded due to incomplete submission. Thus, 251 responses were analyzed as descriptive analyses. Correlation analysis and Chi-square tests were performed to find any association between demographic variables and years of experience in practice with KAP of using apex locators by endodontists. Results: In this study, it was observed that the knowledge of the majority of endodontic practitioners was fair, with a positive attitude and practice of using apex locators. Knowledge of the study participants was significantly (P ≤ 0.05) associated with the good attitude and practice of the study participants. Furthermore, years of experience in practice have a positive association with the KAP of endodontists. Conclusion: It can be concluded that endodontists have better clinical acceptance, as they show positive attitudes and practices for using apex locators for working length determination.