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A novel auxiliary switch dc-dc converter with coupled inductor is presented in this paper. The proposed circuit achieves loss-less switching for both the main and auxiliary switches without increasing the main device current/voltage rating. A tapping in the pole inductor is added for the purpose of commutation. The proposed circuit is capable of operation at elevated switching frequencies of several hundreds of kHz, in a range of line and load variations. The proposed circuit is applicable to all isolated and non-isolated dc-dc converters. The performance and the design equations of the ZVS are identical for all types of dc-dc converters when the throw voltage and the pole current are properly defined. In the sections that follow, operating principle and theoretical analysis of the proposed circuit is outlined through the example of buck converter. Simulation and experimental results of 33 W,400 kHz boost converter are presented. Index Terms--Auxiliary switch converters, coupled inductor, resonant converters, zero current switching (ZCS), zero voltage switching (ZVS).

In this paper, a control strategy for reduced acoustic noise and sensorless operation of a switched reluctance (SR) motor is proposed for heating, ventilation, and air conditioning (HVAC) application, where the magnitude of the dc-bus voltage is controlled as a function of speed and the motor is operated in a single-pulse mode for all speed range. The dc-bus voltage is controlled by incorporating a dc chopper between the three-phase line rectifier and a split dc-link capacitor-type four-switch power converter. Such controller reduces the acoustic noise, provides more accurate position estimation for sensorless operation, and improves the life expectancy of the motor. The algorithm is first simulated through MATLAB/SIMULINK and then tested on a four-phase 8/6-pole 4-kW SR motor. The test results of achieved acoustic noise and improved sensorless operation are presented. Through the proposed method, the acoustic noise is reduced by almost 15 dB compared to the conventional scheme at low-speed regime. The proposed method is intended to drive a fan type of load in HVAC applications, where the dynamic performance requirement is not a stringent criterion. Index Terms--Heating, ventilation, and air conditioning (HVAC) application, low acoustic noise switched reluctance (SR) motor, radial force and vibration, sensorless operation, single-pulse operation.

In this paper, we analyze mutual coupling of switched reluctance (SR) motors with even and odd numbers of phases. We illustrate that SR motors with an even number of phases produce asymmetric mutual flux in different phases. On the other hand, an SR motor with an odd number of phases produces symmetric mutual coupling in all the phases. Then, we explain a practical way of measuring the mutual flux in SR motors and present the test results for an 8/6 pole, four-phase 4 kW motor. We simulated the performance of the SR motor with and without mutual flux, thereby demonstrating the effect of mutual flux on phase current, flux, and average torque. We verified the effect of mutual flux on position estimation by simulation and experiment. We show that appropriate correction for mutual flux may improve the accuracy of estimated position by 3[degrees], which will give better performance of the drive while driven without any shaft sensors. We also show that an SR motor with an odd number of phases is a better choice than one with an even number of phases because of its symmetric mutual coupling, its ability to utilize short flux paths, and the fact that it does not require costly bipolar excitation. Index Terms--Mutual flux, mutual flux measurement, position estimation, SR motor, steady-state performance, symmetric and asymmetric mutual coupling.

This paper proposes a control method that can balance the input currents of the three-phase three-wire boost rectifier under unbalanced input voltage condition. The control objective is to operate the rectifier in the high-power-factor mode under balanced input voltage condition but to give overriding priority to the current balance function in case of unbalance in the input voltage. The control structure has been divided into two major functional blocks. The inner loop current-mode controller implements resistor emulation to achieve high-power-factor operation on each of the two orthogonal axes of the stationary reference frame. The outer control loop performs magnitude scaling and phase-shifting operations on current of one of the axes to make it balanced with the current on the other axis. The coefficients of scaling and shifting functions are determined by two closed-loop proportional-integral (PI) controllers that impose the conditions of input current balance as PI references. The control algorithm is simple and high performing. It does not require input voltage sensing and transformation of the control variables into a rotating reference frame. The simulation results on a MATLAB-SIMULINK platform validate the proposed control strategy. In implementation Texas Instrument's digital signal processor TMS320F240F is used as the digital controller. The control algorithm for high-power-factor operation is tested on a prototype boost rectifier under nominal and unbalanced input voltage conditions. Index Terms--Boost rectifier, current-mode control, high-power-factor rectifiers, input current unbalance, input voltage unbalance, power-factor correction.

In this paper the implementation of a simple yet high performance digital current mode controller that achieves high power factor operation for three phase boost rectifier is described. The indicated objective is achieved without input voltage sensing and without transformation of the control variables into rotating reference frame. The controller uses the concept of resistance emulation for shaping of input current like input voltage in digital Implementation. Two decoupled fixed frequency current mode controllers calculate the switching instants for equivalent single phase boost rectifiers. A combined switching strategy is developed in the form of space vectors to simultaneously satisfy the timing requirements of both the current mode controllers in a switching period. Conventional phase locked loop (PLL) is not required as converter switching is self-synchronized with the input voltage. Analytical formula is derived to obtain the steady state stability condition of the converter. A linear, low frequency, small signal model of the three phase boost rectifier is developed and verified by measurement of the voltage control transfer function. In implementation Texas Instruments's DSP TMS320F240F is used as the digital controller. The algorithm is tested on a 10-kW, 700-V dc, three phase boost rectifier. Index Terms--Distal current mode controller, DSP(TMS320F240) based implementation, high power factor operation, input voltage sensorless control, three phase boost rectifier.

This paper proposes a new strategy for harmonic filtering of a three-phase shunt active filter system. The shunt harmonic filter's control objective is defined as: balance the phase angle of the input current with the phase angle of the line frequency component of the load current. This objective is achieved in digital implementation without sensing the input voltages. The controller uses a phase-shifting method on the sensed input current and then applies the resistor-emulator-type input-current-shaping strategy on the phase-shifted current. In implementation, Texas Instrument's digital-signal-processor-based unit TMS320F240 EVM is used as the digital hardware platform. The control algorithm is computationally simple yet the harmonic filtering performance is high. The analysis, simulation, and experimental results of a three-phase shunt active filter prototype on a 25-A nonlinear load are presented. Index Terms--Digital-signal-processor (DSP) TMS320F240-based implementation, harmonic filter, phase-angle balance (PAB) control, shunt active filter (SAF), voltage-sensorless operation.

In this paper, a new variation of current mode control for high power factor operation of boost rectifier is presented. The general features are no input voltage sensing, no use of multiplier, and no inner loop current regulator. It therefore follows the same control structure as that of the linear peak current mode control and the non linear carrier control. However, it implements a different switching law for the modulator that extends the range of continuous conduction mode of operation. The switching principle of the modulator is predictive, as the actual current equals the reference current at the end of each switching period. The no. of reset integrators required in this modulator for generation of the carrier waveform is two. The steady-state stability analysis of the boost rectifier with the proposed predictive switching modulator (PSM) is presented in this paper. A low-frequency small-signal model of the boost rectifier switched by the PSM is developed for evaluation of the control transfer function. Experimental results on a 400-W boost rectifier prototype are presented. Index Terms--Boost converter, boost rectifier, continuous conduction mode, diode bridge rectifier, NLC, PFC, PSM, steady-state stability analysis.

The objective of this paper is to present a simple yet accurate implementation of a resistor-emulator-type line-current-shaping controller for high-power-factor operation of a flyback rectifier. The important feature is that input voltage sensing is not required. In the circuit realization of the controller, no multiplier is used. Current shaping is performed directly on the input filter inductor current. The modulator uses only one reset integrator for the generation of duty ratio. The analysis presented in this paper shows the effect of input filter capacitance on discontinuous conduction mode of operation of the flyback inductor. Design equations for selection of the input filter components are derived. A low-frequency small-signal model of the rectifier is developed and verified by measurement up to 1 kHz. The performance of the controller is first tested by the SABER circuit simulator package. Then, a 100-W 110-V ac input 50-V dc output single-phase flyback rectifier prototype is built for experimental verification. Index Terms--Current-mode control, discontinuous-conduction-mode operation, flyback rectifier, high-power-factor rectifiers, power-factor correction.

Discusses the analysis and performance evaluation of a distribution STATCOM for compensating fluctuations. Hardware set-up; Control implementation; DC bus voltage control.

Introduction: Mid-day meal programmes (MDM) were introduced in India to improve school attendance, nutritional status and educational outcomes of school children. Numerous primary studies have examined the impact of the MDM programmes on both nutritional and educational outcomes in various settings across the country. However, synthesising the findings from these studies has been challenging. To address this gap, we conducted a systematic review to assess the effects of MDM programmes on the nutritional and academic outcomes of school children in India., Methods: A comprehensive literature search was conducted, and relevant studies published between 1997 and 2022 were included. Two reviewers independently conducted study selection, data extraction and risk of bias assessment. The results were synthesised descriptively., Results: The systematic review included 31 studies. Among them, 16 studies focused on academic outcomes, while 18 studies reported children's nutritional status. Studies on MDM Scheme (MDMS) in children show mixed results on nutritional outcomes. While some studies show marginal improvements in height and weight measurements, others show no significant improvement. Regular MDMS access improves enrollment, attendance and retention rates for children, with lower dropout rates and higher academic achievement. However, its impact on academic performance remains unclear., Conclusion: The MDM programme in India was effective in improving the academic achievement and a few nutritional outcomes of school children, underscoring the importance of sustaining MDM programmes in India., Protocol Registration Number: The review was prospectively registered in PROSPERO (CRD42023391776). Available from: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023391776., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Introduction: Oral cancer is the sixth most prevalent cancer type worldwide. Patients are placed in a crippling predicament due to the functional and psychosocial difficulties brought on by the illness and its treatments. Both surgeons and maxillofacial prosthodontists may encounter challenges with reconstruction and therapy following cancer treatment. Over 20 years, the fibula has remained the mainstay of reconstructions for head and neck cancer. Maxillary and mandibular jaws with fibula reconstructions can use fixed or removable prosthetic rehabilitation solutions. The proposed scoping review aims to ascertain the volume and nature of evidence concerning the difficulties and corrective measures in the prosthetic rehabilitation of fibula-reconstructed head and neck cancer cases. The findings will aid in improving the prosthetic treatment care for the affected population., Materials and Methods: The Joanna Briggs Institute (JBI) scoping review protocol will be followed in developing and reporting the scoping review methodology. Methods to identify the relevant literature will involve the systematic search of databases like PubMed, Scopus, Google Scholar, Cochrane Library, and gray literature sources for pertinent articles on the subject. Only papers published in English literature will be considered for the review, and the data collection period is limited to the past 20 years. The screening process will utilize defined inclusion/exclusion criteria for Title/Abstract and Full-text screening by two independent reviewers in covidence, and a third reviewer will resolve any conflicts. The data extracted will include specific details about the participants, concept, population, study methods, challenges encountered during prosthetic rehabilitation, and their management. Inductive thematic analysis and descriptive statistics will be applied where appropriate. The narrative synthesis of the evidence will be accomplished through data extraction in a tabular format, and the results will be presented as a narrative summary., Competing Interests: There is no conflicts of interest in this project.Sponsorships or competing interests that may be relevant to content are disclosed at the end of this article., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc.)

Background: There exists a high burden of oral diseases. Yet, the utilization of oral health care remains low. Understanding how, when, and why/why not individuals utilize dental healthcare resources is essential for planning health services and developing policies as it reflects the population's oral health needs, helps allocate resources efficiently, and formulate policies that are tailored to address their needs., Objectives: To assess the utilization of dental health services and its associated factors along with barriers and facilitators among adults residing in Ernakulam district, Kerala, using the Anderson healthcare model for healthcare utilization., Methods: A mixed-method study was conducted among adults aged 18 years and above in urban and rural wards of Ernakulam district using the cluster sampling method. Univariate and multivariate analysis were used for the quantitative part, and thematic analysis was used for the qualitative aspect. The total sample size was 544., Results: The dental healthcare utilization was 15.4 ± 2.9 % among the study participants. Age and education were associated with dental healthcare utilization. The level of education, pain, and self-consciousness of oral diseases were independent predictors. Barriers identified were negative attitudes, financial restraints, and difficulty in access, while facilitators were trust in service providers, availability of services, and a positive attitude., Conclusion: Utilization was poor despite the perceived need for oral health care. This was affected by several personal and system-level facilitators and barriers., Competing Interests: There are no conflicts of interest., (© 2024 The Authors.)

Background: The rise of depression, anxiety, and suicide rates has led to increased demand for telemedicine-based mental health screening and remote patient monitoring (RPM) solutions to alleviate the burden on, and enhance the efficiency of, mental health practitioners. Multimodal dialog systems (MDS) that conduct on-demand, structured interviews offer a scalable and cost-effective solution to address this need., Objective: This study evaluates the feasibility of a cloud based MDS agent, Tina, for mental state characterization in participants with depression, anxiety, and suicide risk., Method: Sixty-eight participants were recruited through an online health registry and completed 73 sessions, with 15 (20.6%), 21 (28.8%), and 26 (35.6%) sessions screening positive for depression, anxiety, and suicide risk, respectively using conventional screening instruments. Participants then interacted with Tina as they completed a structured interview designed to elicit calibrated, open-ended responses regarding the participants' feelings and emotional state. Simultaneously, the platform streamed their speech and video recordings in real-time to a HIPAA-compliant cloud server, to compute speech, language, and facial movement-based biomarkers. After their sessions, participants completed user experience surveys. Machine learning models were developed using extracted features and evaluated with the area under the receiver operating characteristic curve (AUC)., Results: For both depression and suicide risk, affected individuals tended to have a higher percent pause time, while those positive for anxiety showed reduced lip movement relative to healthy controls. In terms of single-modality classification models, speech features performed best for depression (AUC = 0.64; 95% CI = 0.51-0.78), facial features for anxiety (AUC = 0.57; 95% CI = 0.43-0.71), and text features for suicide risk (AUC = 0.65; 95% CI = 0.52-0.78). Best overall performance was achieved by decision fusion of all models in identifying suicide risk (AUC = 0.76; 95% CI = 0.65-0.87). Participants reported the experience comfortable and shared their feelings., Conclusion: MDS is a feasible, useful, effective, and interpretable solution for RPM in real-world clinical depression, anxiety, and suicidal populations. Facial information is more informative for anxiety classification, while speech and language are more discriminative of depression and suicidality markers. In general, combining speech, language, and facial information improved model performance on all classification tasks., Competing Interests: JC, DB, and AH were employed full-time by Clarigent Health. VRi, MN, and VRa were full-time employees of Modality.AI. JW-B is a part-time consultant and is sponsored by a grant from Clarigent Health. The above interests do not alter our adherence to Frontiers Media's policies. Clarigent Health and Modality did not influence or restrict the submission of this publication., (Copyright © 2023 Cohen, Richter, Neumann, Black, Haq, Wright-Berryman and Ramanarayanan.)

Upon perceiving sensory errors during movements, the human sensorimotor system updates future movements to compensate for the errors, a phenomenon called sensorimotor adaptation. One component of this adaptation is thought to be driven by sensory prediction errors-discrepancies between predicted and actual sensory feedback. However, the mechanisms by which prediction errors drive adaptation remain unclear. Here, auditory prediction error-based mechanisms involved in speech auditory-motor adaptation were examined via the feedback aware control of tasks in speech (FACTS) model. Consistent with theoretical perspectives in both non-speech and speech motor control, the hierarchical architecture of FACTS relies on both the higher-level task (vocal tract constrictions) as well as lower-level articulatory state representations. Importantly, FACTS also computes sensory prediction errors as a part of its state feedback control mechanism, a well-established framework in the field of motor control. We explored potential adaptation mechanisms and found that adaptive behavior was present only when prediction errors updated the articulatory-to-task state transformation. In contrast, designs in which prediction errors updated forward sensory prediction models alone did not generate adaptation. Thus, FACTS demonstrated that 1) prediction errors can drive adaptation through task-level updates, and 2) adaptation is likely driven by updates to task-level control rather than (only) to forward predictive models. Additionally, simulating adaptation with FACTS generated a number of important hypotheses regarding previously reported phenomena such as identifying the source(s) of incomplete adaptation and driving factor(s) for changes in the second formant frequency during adaptation to the first formant perturbation. The proposed model design paves the way for a hierarchical state feedback control framework to be examined in the context of sensorimotor adaptation in both speech and non-speech effector systems., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Kim et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Introduction: Children's learning abilities suffer when their oral health is compromised. Inadequate oral health can harm children's quality of life, academic performance, and future success and achievements. Oral health problems may result in appetite loss, depression, increased inattentiveness, and distractibility from play and schoolwork, all of which can lower self-esteem and contribute to academic failure. An oral health curriculum, in addition to the standard school curriculum, may instil preventive oral hygiene behaviour in school students, enabling them to retain good oral health for the rest of their lives. Because most children attend school, the school setting is the most effective for promoting behavioural change in children. A 'health-promoting school' actively promotes health by enhancing its ability to serve as a healthy place to live, learn and work, bringing health and education together. Making every school a health-promoting school is one of the joint objectives of the WHO and UNICEF. The primary objective of this proposed study is to assess the effectiveness of an oral health curriculum intervention in reducing dental caries incidence and improving oral hygiene behaviour among high school children in grades 8-10 of the Ernakulam district in Kerala, India. If found to be effective in changing children's behaviour in a positive way, an oral health curriculum may eventually be incorporated into the school health curriculum in the future. Classroom interventions can serve as a cost-effective tool to increase children's oral health awareness., Methods and Analysis: This protocol presents a cluster randomised trial design. It is a parallel-group comparative trial with two arms having a 1:1 distribution-groups A and B with oral health curriculum intervention from a dental professional and a schoolteacher, respectively. High schools (grades 8-10) will be selected as clusters for the trial. The minimum cluster size is 20 students per school. The total sample size is 2000 high school children. Data will be collected at three time points, including baseline, after 1 year (mid-term) and 2 years (final), respectively. The outcome measures are Decayed, Missing and Filled Teeth Index; Oral Hygiene Index-Simplified; and knowledge, attitude and behaviour. Data collection will be done by clinical oral examination and questionnaire involving oral health-related knowledge, attitude and behaviour items., Ethics and Dissemination: Ethical approval was obtained from the Institutional Ethics Committee of Amrita Institute of Medical Sciences and Research Centre (dated 19 July 2022, no: IEC-AIMS-2022-ASD-179)., Trial Registration Number: Clinical Trial Registry of India (CTRI/2022/09/045410)., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

This review was designed to assess the pooled prevalence of early childhood caries (ECC) in India. An electronic data search was done in PubMed/MEDLINE and Scopus databases in October 2020. Epidemiological surveys assessing the prevalence of ECC were included, and data on gender, geographic region, sampling strategy, feeding habits, and dmft values were extracted. The risk of bias was assessed, and a meta-analysis was performed for pooled prevalence and mean dmft values. The selection of articles, data extraction, and validity assessment were done independently by the two reviewers (ID and RV). A third reviewer (CJ) resolved any conflict between these two reviewers. A total of seventy-one studies were included for quantitative analysis. The pooled prevalence of ECC estimated from 71 studies with 69,330 participants is 46.9% (confidence interval [CI] 46.5-47.2). Males had a higher prevalence of ECC (47%, CI: 46.4-47.6,40 studies, 26,840 participants) than females (43.8%, CI: 43.2-44.2,40 studies, 24,389 participants). Region-wise analysis showed the highest number of studies (44) in southern India, with a sample size of 35,988 with a pooled prevalence of 44.6% (CI: 44-45.1). The pooled mean dmft (random effect) is 2.23 (1.97-2.48), with males having a higher proportion of 2.26 compared to 2.23 in females. The pooled prevalence of ECC was 46.9%, and the pooled mean was 2.23. The results from this study state that one in every two children in India is suffering from ECC, reflecting its public health relevance., Competing Interests: None

Introduction: Dental caries in the adult population that require preventive and therapeutic treatment are generally neglected in rural communities. The determination of the effectiveness of the application of 38% silver diamine fluoride (SDF) in arresting caries lesions when combined with atraumatic restorative treatment (ART) is very important, as it serves as a preventive and restorative procedure to regain the function of the permanent dentition. The assessment of optimal SDF application with ART, in comparison with ART alone, in managing cavitated carious lesions in a pragmatic setting, is the need of the hour to recommend optimal dental care, especially in rural settings which have minimal access to comprehensive dental care., Methods and Analysis: The clinical trial will enrol 220 adults (18-65 years) with cavitated carious lesions attending the Amrita School of Dentistry in the Ernakulam district, India. This study is a randomized, controlled trial with a 1:1 allocation ratio in two parallel groups. Study arm 1 will receive 38% SDF application and ART, and study arm 2 will receive ART only. A digital radiograph will be taken immediately after restoration (baseline) as well as at the end of the 6th month for evaluation of caries arrest. The assessment of the survival of the restoration will be done on the 7th day, 30th day, and at the end of the 6th month. The final analysis would include both the tooth and person levels., Ethics and Dissemination: This trial adheres to the principles of the Declaration of Helsinki and the guidelines of the Indian Council of Medical Research (ICMR). This study protocol has been approved by the Institutional Review Board. This trial has been registered prospectively with the Clinical Trial Registry of India (Registration No: CTRI/2021/12/038816).

Background: Transformation of education to virtual mode during COVID-19 pandemic was a major challenge for a clinical specialty like dentistry., Materials and Methods: A sequential explanatory mixed method was adopted with quantitative dominant design. A self-reported questionnaire on attitude and perceptions toward online learning were distributed among dental undergraduate students. The qualitative arm explored perceptions of online teaching among various stakeholders and thematic content analysis was performed., Results: A total of 141 responses were obtained, about 21% of them felt online classes to be highly useful and 78% felt it was moderately useful. About 80% of the students were satisfied with the online education. About 40% of participants felt internet connectivity was a frequent issue. The qualitative data analysis revealed five emergent themes of lecture content and delivery, instructional control, resource management, interaction, and evaluation exploring the perceptions of various stakeholders toward online learning and provided several insights., Conclusion: Though online education cannot be compared to traditional education in a clinical specialty like dentistry, it does have its advantages and a portion of student learning can be conducted through this mode., Competing Interests: There are no conflicts of interest., (Copyright: © 2022 Journal of Education and Health Promotion.)

The Maeda model was used to generate a large set of vocoid-producing vocal tract configurations. The resulting dataset (a) produced a comprehensive range of formant frequencies and (b) displayed discrete tongue body constriction locations (palatal, velar/uvular, and lower pharyngeal). The discrete parameterization of constriction location across the vowel space suggests this is likely a fundamental characteristic of the human vocal tract, and not limited to any specific set of vowel contrasts. These findings suggest that in addition to established articulatory-acoustic constraints, fundamental biomechanical constraints of the vocal tract may also explain such discreteness., (© 2021 Author(s).)

Background: A large number of trials has been conducted using curcumin as the main ingredient in mouth rinses, topical oral gel, subgingival irrigant, locally delivered gel and locally delivered chips to reduce gingival inflammation and probing pocket depth. However, the results of these trials vary and are debatable., Objective: To evaluate the effectiveness of oral curcumin products as compared to the routinely used ones in reducing gingival inflammation and probing pocket depth in adults., Methods: Electronic databases such as Pubmed/Medline and Cochrane Library and hand searching was done for randomised controlled trials (RCTs), which yielded 148 results, of which 27 RCTs compared curcumin products with routinely used ones. Meta-analysis was conducted to check for plaque reduction, gingival inflammation and pocket depth., Results: 963 participants in the 27 RCT studies were considered for a systematic review. We found that for a long-term evaluation of probing pocket depth in nine studies each with 400 participants, there was a statistically significant difference in the reduction when curcumin topical gel was used as compared with the control [SMD -0.87, 95% CI: -1.31 to -0.43]. However, in the evaluation of short-term plaque and gingival scores, we found no statistically significant differences in the reduction when curcumin mouth rinse was used [SMD -0.76, 95% CI: -2.25 to 0.73] and [MD: -0.09, 95% CI: -0.29 to 0.10]., Conclusion: Curcumin topical and local delivery gel, mouth rinses and sub-gingival irrigants were found to be equally effective compared to the routinely used agents for reduction of plaque and gingival inflammation. Curcumin local delivery gel had greater reduction in probing pocket depth., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2021 The Authors.)

Background: Individual studies conducted in Asian countries have reported higher risk of periodontitis among smokeless tobacco (SLT) users in comparison to non-users. Therefore, a systematic review was conducted to summarize the available evidence on this topic., Methods: Prominent electronic databases were searched using pre-decided MeSH terms and keywords. Screening of titles and abstracts, full text reading, quality assessment and data extraction was done by two investigators independently. The Newcastle-Ottawa scale was used for risk of bias assessment of eligible studies. Meta-analysis was performed for four periodontal outcomes (periodontal pocket depth, loss of attachment, clinical attachment level and gingival recession). A sensitivity analysis was also performed., Results: Of the 546 citations, 367 were screened for eligibility. Finally, 89 studies were shortlisted for full text reading, of which, 36 were found eligible for qualitative analysis. Most of the studies were conducted in India (n=22), were of cross-sectional design (n=33), utilized purposive sampling and 24 studies were included for meta-analysis (n=28) and done on hospital-based population (n=26). Only 13 (37.1%) studies achieved a score of more than 50% (5/10 stars) on quality assessment scale. SLT users had higher odds of greater periodontal pocket depth greater than 4 mm (OR=3.64), gingival recession (OR=1.71) and loss of attachment 4-5 mm (OR=2.83) and mean difference of 1.7 mm for Clinical Attachment Level compared to non-users., Conclusion: The studies included in this review suggests that SLT users have poorer periodontal health in comparison to non-users. But most of this evidence comes from cross-sectional studies. Longitudinal studies with rigorous methodology are required to support this elucidation. Registration: This systematic review protocol has been registered in PROSPERO (CRD42019122964).

Tooth loss remains a significant deterrent to oral health and adversely affects the dietary intake and nutritional status of individuals compromising their general health. It is a debilitating and irreversible condition and is considered as the "final marker of disease burden for oral health." The prevalence of tooth mortality and its causes has been studied for many years through point prevalence studies; however, there is a need to generate a national representative data. This study aimed to systematically review the available literature measuring the prevalence of tooth mortality in India. We searched the following databases for studies that had assessed the prevalence of tooth mortality in India: PubMed/Medline, PubMed Central, and Scopus. This yielded 36 studies, of which 16 eligible cross-sectional studies assessing the prevalence among those 18 years and above were included. Meta-analyses using the random-effects model were conducted for tooth mortality outcomes which stratified for different covariates such as age groups, gender, geographic region, population group, type of index, and reason for loss using MetaXL Version 5.3 Software, Netherlands developed by Dr Jan J Barendregt. Pooled prevalence was used to estimate the overall effect, with 95% confidence intervals (CI). A total of 13,662 adults participated in the 16 studies. We found that the overall prevalence of complete tooth mortality (loss of 32 teeth) was 10.7% (95% CI: 10.2%-11.2%, 16 studies, n = 2249) and partial tooth mortality (having one or more teeth) was 58.8% (95% CI: 57.9%-59.6%, 16 studies, n = 7526). Rural area adults showed twice 61% (60.5%, 95% CI: 58.9-62.1, 7 studies) than urban adults. Females had higher partial tooth mortality (48.2%%), whereas males higher complete tooth mortality (20.2%). There was higher methodological heterogeneity of included studies. Nearly 35% of adults have complete or partial tooth mortality. Greater tooth mortality indicates the burden of the prosthetic needs., Competing Interests: There are no conflicts of interest., (Copyright: © 2021 Contemporary Clinical Dentistry.)

Introduction: Silver Diammine Fluoride (SDF) is an emerging caries preventive treatment option that is inexpensive, safe, and easily accessible. The evidence is clear that the use of SDF at concentrations of 38% is effective for arresting caries in primary teeth. However, the determination of an optimal SDF application frequency for a cavitated lesion in pragmatic settings is warranted especially among high dental caries risk groups. Hence, the primary objective of this clinical trial is to compare the effectiveness of annual, bi-annual, and four times a year application of 38% SDF application in arresting active coronal dentinal carious lesions on primary teeth among tribal preschool children aged 2-6 years. Methods and Analysis: This study is designed as a randomized, controlled trial consisting of three parallel arms with an allocation ratio of 1:1:1. The trial will enroll 480 preschool tribal children with a cavitated carious lesion (2-6 years) attending a primary health care Centre in Wayanad district, India. Each arm will receive 38% SDF application on an annual (baseline), bi-annual (baseline and 6 months), and four times a year (baseline, 2nd, 4th, and 8th week), respectively. The analysis will be performed both at the tooth- and person-level. Ethics and Dissemination: This trial will be conducted following the principles of the Declaration of Helsinki and local guidelines (Indian Council of Medical Research). The protocol has been approved by Institutional Review Committee (IRB). This trial has been registered prospectively with the Clinical Trial Registry of India [Registration No: CTRI/2020/03/024265].

A hallmark feature of speech motor control is its ability to learn to anticipate and compensate for persistent feedback alterations, a process referred to as sensorimotor adaptation. Because this process involves adjusting articulation to counter the perceived effects of altering acoustic feedback, there are a number of factors that affect it, including the complex relationship between acoustics and articulation and non-uniformities of speech perception. As a consequence, sensorimotor adaptation is hypothesised to vary as a function of the direction of the applied auditory feedback alteration in vowel formant space. This hypothesis was tested in two experiments where auditory feedback was altered in real time, shifting the frequency values of the first and second formants (F1 and F2) of participants' speech. Shifts were designed on a subject-by-subject basis and sensorimotor adaptation was quantified with respect to the direction of applied shift, normalised for individual speakers. Adaptation was indeed found to depend on the direction of the applied shift in vowel formant space, independent of shift magnitude. These findings have implications for models of sensorimotor adaptation of speech.

Aim: The aim of this review is to discuss the implications of COVID-19 on various aspects of dental care., Background: The COVID-19 pandemic had suspended dental practice globally for over 3 months. While dental practice is being resumed cautiously, standard infection control protocols that were traditionally overlooked are now being strictly implemented. Post-COVID-19, dental care is expected to see a drastic change in the way it is practiced., Review Results: With a view on the natural history and disease dynamics of COVID-19, this review reports various aspects of dental care, viz., patient triaging, engineering and work practice controls, and administrative, financial, and ethical aspects of dental care during and after COVID-19 pandemic. Current evidence-based recommendations with regard to infection-control practices are discussed. A call for universal oral health care with suggestions regarding integration of medical and health care is also proposed., Conclusion: COVID-19 is expected to be a watershed moment in the field of dentistry. While we expect to see positive changes in safe delivery of dental care, an increase in cost of availing care is imminent., Clinical Significance: The practice of dentistry and dental infection control has undergone dimensional changes due to bloodborne infectious diseases such as hepatitis B virus infections and human immunodeficiency virus epidemic. Due to these pandemics, many regulatory organizations have provided safety recommendations and guidelines that impact the dental practice. Currently, we are faced with a highly infective disease with a high mortality rate among people with comorbidities and of predominantly droplet transmission and no concrete safety recommendations and guidelines. This manuscript addresses multiple issues, gaps, and pragmatic solutions in controlling transmission of SARS-CoV-2 in dental settings, during and after the pandemic.

Background: To systematically review the effectiveness primary molar pulpotomy based on the clinical and radiographic outcomes using lasers over the conventional therapies., Material and Methods: This systematic review and meta-analysis included Randomized or Quasi-randomized trials comparing LASER with conventional pulpotomy therapies (formocresol, ferric sulphate, MTA or calcium hydroxide) with atleast 6-month follow-up period was included. Risk of bias of included studies was assessed and metanalysis was done using RevMan software., Results: Of the 1383 articles that were searched, only 14 studies were included for qualitative synthesis and 10 for meta- analysis. There was no statistically significant difference in clinical success rate [OR 0.99, 95%CI (0.19,5.22)] or radiographic success rate [OR 0.77, 95%CI (0.31,1.87)] of LASER therapy compared to Formocresol in primary molar pulpotomy for 6 months. No statistically significant difference were found in clinical success rate [OR 1.04, 95%CI (0.35,3.07)] and radiographic success rate [OR 0.71, 95%CI (0.37,1.35)] at 12 month follow-up also. Comparison of LASER with Ferric Sulphate also did not show a statistically significant difference., Conclusions: Meta-analysis showed no statistically significant difference in clinical and radiographic outcomes of LASER pulpotomy with conventional pulpotomy (formocresol and ferric sulphate) at 6 and 12 months follow-up. However, there was considerable risk of bias in the included studies. Key words: Pulp therapy, Laser, formocresol., Competing Interests: Conflicts of interest None declared., (Copyright: © 2020 Medicina Oral S.L.)

Objectives: The health system of Kerala, India has won many accolades in having health indicators comparable to developed countries. But oral health has not received its due importance at the policy level. With the burden of oral diseases on the rise in the state, a critical introspection of the existing system is warranted. The objective of this review was to assess the oral health care system in Kerala to provide policy solutions., Methods: This study adopted a mixed methodological approach that gathered information from the primary and secondary sources, which included health facility surveys, key informant interviews, review of published literature, and websites of governmental and non-governmental bodies. The WHO framework of health system building blocks was adapted for the assessment., Results: A review of epidemiological studies conducted in Kerala suggests that the prevalence of oral diseases is high with the prevalence of dental caries at the age of 12 years ranging from 37-69%. The state has a dentist population ratio of 1:2200 which is well within the prescribed ratio by WHO (1:7500). Only 2% of dentists in Kerala work with government sector catering to 0.6 million of the approximately 33.4 million population. This point to the absence of oral care in first contact levels like primary health centers. Service delivery is chiefly through the private sector and payment for dental care is predominantly through out-of-pocket expenditure., Conclusion: Despite having the best health indicators, the oral health system of Kerala is deficient in many aspects. Reorientation of oral health services is required to combat the burden of diseases., Competing Interests: There are no conflicts of interest., (Copyright: © 2020 Journal of Family Medicine and Primary Care.)

We present a new computational model of speech motor control: the Feedback-Aware Control of Tasks in Speech or FACTS model. FACTS employs a hierarchical state feedback control architecture to control simulated vocal tract and produce intelligible speech. The model includes higher-level control of speech tasks and lower-level control of speech articulators. The task controller is modeled as a dynamical system governing the creation of desired constrictions in the vocal tract, after Task Dynamics. Both the task and articulatory controllers rely on an internal estimate of the current state of the vocal tract to generate motor commands. This estimate is derived, based on efference copy of applied controls, from a forward model that predicts both the next vocal tract state as well as expected auditory and somatosensory feedback. A comparison between predicted feedback and actual feedback is then used to update the internal state prediction. FACTS is able to qualitatively replicate many characteristics of the human speech system: the model is robust to noise in both the sensory and motor pathways, is relatively unaffected by a loss of auditory feedback but is more significantly impacted by the loss of somatosensory feedback, and responds appropriately to externally-imposed alterations of auditory and somatosensory feedback. The model also replicates previously hypothesized trade-offs between reliance on auditory and somatosensory feedback and shows for the first time how this relationship may be mediated by acuity in each sensory domain. These results have important implications for our understanding of the speech motor control system in humans., Competing Interests: The authors have declared that no competing interests exist.