Bleaching techniques in primary teeth: a systematic review

OBJECTIVE

Discolouration of primary teeth, often attributed to trauma and pulpal infection, is a prevalent concern that can significantly impact the esthetics and self-esteem of children. To address this issue, bleaching techniques have emerged as a viable treatment option. This systematic review aims to provide a comprehensive summary of the effectiveness of bleaching agents in managing discoloured primary teeth.

METHODS

Two reviewers independently conducted an electronic database search using PubMed, EMBASE, LILACS, CINAHL via EBSCO, Scopus, and Web of Science until September 26,2023. In vitro studies and case reports that assessed the quantifiable success were included. The present review utilized Distiller SR software for data extraction. The protocol of this study was registered in PROSPERO (International Prospective Register of Systematic Reviews) (CRD42022329831). The quality of studies was analysed with Cochrane tool and the JBI checklist.

RESULTS

The search retrieved 1845 references of which 14 studies were included for qualitative analysis. There were 8 in vitro studies and 6 case reports included in this systematic review. There were 299 teeth samples in the in vitro studies and 18 teeth were assessed in the case reports. All the 18 teeth (6 case reports) showed considerable shade improvement within 7-14 days. However, only 3 teeth were followed up for a period of 12-24 months. Substantial shade improvement was also observed in samples in the in vitro studies.

CONCLUSION

This systematic review has comprehensively examined the various bleaching agents and methods for the management of discoloured primary teeth. However, it is crucial to recognize that the available evidence is from case reports and is insufficient to make a clinical recommendation.

Cognitive Function in Early Onset Type 1 Diabetes in Children

OBJECTIVES

To assess cognitive function and factors affecting it in Indian children with early-onset type 1 diabetes (T1D) (less than 6 y).

METHODS

This cross-sectional, single-centre study recruited children diagnosed with T1D before 6 y of age and having a disease duration of at least 2 y, as cases. Controls were age- and sex-matched apparently healthy children or siblings. Children with birth asphyxia, intellectual disability, syndromic children, or pre-existing psychiatric illness were excluded. Enrolled children underwent cognitive assessment using Malin's Intelligence Scale for Indian Children (MISIC), and scores in various subtests were compared between cases and controls.

RESULTS

A total of 60 children were enrolled in each group. When compared to controls, cases had significantly lower scores on most subtests, verbal, performance and overall Intelligence Quotient (IQ- 100.62 ± 3.26 vs. 103.23 ± 1.22). HbA1c >9%, severe hypoglycemia and lesser duration since the last diabetic ketoacidosis (DKA) episode significantly correlated with lower neurocognitive scores.

CONCLUSIONS

Children with early onset T1D showed significant deficits in various cognitive domains and IQ. Poor glycemic control, higher glycemic variability and exposure to severe hypoglycemia are risk factors for poor cognitive outcomes in these children. Further longitudinal studies could potentially aid in a finer understanding of factors affecting cognitive functioning in T1D children in developing countries.

Mechanical Properties and Clinical Success of Intracanal Posts in Primary Maxillary Anterior Teeth: A Systematic Review and Meta-analysis

Background

Intracanal posts are commonly used to restore lost permanent/primary tooth structure and the smile of the patient.

Aim

This systematic review aims to evaluate the clinical success of intracanal posts used in primary maxillary anterior teeth and compare their mechanical properties.

Methods

An extensive literature search was performed using Medline via PubMed, Embase via embase.com, LILACS, CINAHL via EBSCO, Cochrane Oral Health Group Specialized Register, Scopus, and Web of Science until December 2021 and was updated till December 2022. In vivo and in vitro studies in the English language that assessed clinical success and mechanical properties were included. Distiller SR software was used for everything from title screening to data extraction.

Results

A total of 30 studies were analyzed, including 11 in vivo and 19 in vitro studies. Four studies were included in a meta-analysis, and all 30 studies qualified for qualitative analysis. The meta-analysis showed that fiber posts are clinically superior to composite resin posts (CRPs) (p = 0.02). No significant difference was observed between the fracture resistance of CRPs and no posts (p = 0.73). Most of the included studies showed a high risk of bias.

Conclusion

Conclusive evidence about the effectiveness of various intracanal posts cannot be established. This is due to the limited number of clinical trials and included studies of low to moderate quality with a high risk of bias. To validate the use of posts in primary maxillary anterior teeth, further research, including randomized controlled trials (RCTs) of higher quality, is required.

Clinical significance

The use of intracanal posts in primary teeth is a commonly used treatment modality among pediatric dentists. However, the quality of the evidence to support its use is low. This systematic review provides a comprehensive summary of the current literature and highlights the need for further research. Results were interpreted with caution, as the evidence supporting the use of intracanal posts in primary teeth is limited.

How to cite this article

Shanmugam Y, Raghu A, Muthu MS, et al. Mechanical Properties and Clinical Success of Intracanal Posts in Primary Maxillary Anterior Teeth: A Systematic Review and Meta-analysis. Int J Clin Pediatr Dent 2023;16(S-3):S293-S305.

Comparison of conventional preparation with modified access preparation on fracture resistance of primary molars - A finite element analysis

Objective

To investigate the influence of Conventional Straight (CS) line and Modified Straight (MS) line access preparations with various restorative materials on the fracture resistance of primary molars using Finite Element Analysis (FEA).

Methodology

Three FEA models for each of the primary molars were divided into Group I- Intact tooth model; Group II- Model with CS outline and Group III- Model with MS outline. Based on the restorative material used, Group II and III were further subdivided into subgroup 1- GIC restoration, subgroup 2 - composite resin with GIC base and subgroup 3- Stainless Steel Crown (SSC). Each model was subjected to 5 different force loads directed at the occlusal surface. Maximal von Mises (VM) stresses calculated from stress distribution patterns.

Result

The maximum displacement, in all the models of primary molars were seen in GIC restored models in molars with both CS and MS access whereas the minimal displacement was seen in the SSC restored molars of MS group.

Conclusion

In primary maxillary second molar and mandibular first and second molar with intact marginal ridges, the fracture resistance of tooth with MS outline restored with GIC base followed by Composite resin was comparable with the tooth restored with SSC and CS outline.

Clinical outcome

Based on the results of this FEA analysis, composite restorations with MS outline would be appropriate for endodontically treated primary molars that have intact margins.

NK cells are associated with immunometabolic response to a single exercise exertion in heart failure patients

Background

Increased systemic inflammation and metabolic dysfunction are observed in heart failure with reduced ejection fraction (HFrEF). On the other hand, cardiorespiratory exercise testing (CPET) exerts a physical challenge and initiates the activation of the immune system, including acute release of natural killer (NK) cells into the circulation, and several metabolic pathways.

Aim

To characterize the inflammatory and metabolic alterations of HFrEF patients in response to an acute exercise challenge, and after 2 hours of recovery.

Methods

Participants with HFrEF (n=16), age and sex matched controls (CON, n=13) were investigated at baseline, immediately after and 2 hours after CPET. Clinical and physiological parameters, leukocyte profile, plasma cytokines and metabolites were assessed along with inflammatory and metabolic parameters at all three time points. NK cell counts and morphological/activation parameters in different contexts were examined. Further, the time-dependent coordination of NK cell numbers post-exercise with tryptophan metabolism and plasma triglycerides were assessed. NK cells were isolated from blood of healthy donors for ex vivo proof-of-principle experiments, including phenotype polarization and NK cell specific tryptophan metabolism.

Results

Cardiovascular risk profiles as well as leukocyte, cytokine and metabolic parameters at baseline were similar in CON and HFrEF. Immediately after CPET, lactate, and NK T cell blood counts were significantly increased in both groups. In HFrEF but not CON, platelet aggregates with NK cells, CD8+ cytotoxic T cells and “classical” CD14++CD16-monocytes, phosphatidylcholines and triglycerides were increased. After 2h of recovery, almost all altered parameters returned to baseline in CON. In contrast, blood counts and morphological markers of inflammatory effector cell types, including CD8+ T cells and neutrophils remained elevated in HFrEF. NK cells remained elevated after the recovery period and correlated with levels of various triglyceride species in the HFrEF patients. Tryptophan levels in plasma were reduced by acute exercise and the kynurenine to tryptophan ratio was increased and correlated with increase in NK and NK-T cell counts, as well as IL-12 plasma levels. Treatment with IL-12 led to increased synthesis of kynurenine from tryptophan, expression of indoleamine 2,3-dioxygenase and abundance of regulatory CD56bri NK cell phenotypes ex vivo. Secretome of untreated NK cells impaired cellular respiration, increased glycolysis/oxidation ratio in skeletal muscle cells, and increased the release of triglycerides from hepatocarcinoma cells.

Conclusion

CPET induced a complex acute immunometabolic response, whose restitution to baseline levels differed between HFrEF and healthy controls. Exercise-induced changes in NK cell metabolism and phenotype shift might modulate cellular respiration in myocytes and release of triglycerides by hepatocytes in HFrEF and in CON.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): DZHK (German Centre for Cardiovascular Research)

Comparison of viscosities of human breast milk versus infant milk formulae with and without addition of sweetening agents

CONTEXT

Early childhood caries is a major health problem affecting children worldwide. Although incorrect feeding practices hold a prime position in the etiology, there are gaps in the literature pertaining to the physical properties of milk.

AIM

To assess the viscosity of human breast milk (HBM) versus infant milk formulae, with and without the addition of sweetening agents.

MATERIALS AND METHODS

All commercially available infant milk formulae (60 samples) and breast milk from 30 donor mothers were assessed for viscosity using Brookfield DV2T viscometer. The study period was from April 2019 to August 2019. Viscosity of infant milk formulae sweetened with sugar, honey, and brown sugar was further investigated and compared with that of HBM.

STATISTICAL ANALYSIS

Inter-group and intra-group mean viscosity was compared using independent t-test and repeated-measures ANOVA.

RESULTS

Viscosity of HBM ranged from 18.36 centipoise (cP) to 91.30 cP, the mean viscosity being 45.7 cP. Viscosity values varied for each formula group, the least being as low as 5.1 cP and the highest being 89.3 cP. The mean viscosities of each group were in the range of 33 to 49 cP.

CONCLUSIONS

HBM was found to have a tendency toward higher viscosity than most of the infant milk formulae. Also, varied viscosity values were obtained when commonly used sweetening agents were added to infant milk formulae. Greater viscosity of HBM might increase its adherence to enamel surface leading to prolonged demineralization and potentially altering the caries risk, needs to be investigated further.

Solitary Median Maxillary Central Incisor Syndrome: A Case Report

Aim

This report intends to present a case of solitary median maxillary central incisor syndrome (SMMCI) and its multidisciplinary team approach for diagnosis of other associated anomalies, with special emphasis on their management.

Background

Solitary median maxillary central incisor syndrome is a unique developmental condition characterized by only maxillary central incisor and a series of developmental defects, appearing as a syndrome. The appearance of a single incisor may take place due to the union of two incisor teeth or the absence of tooth germs. The mechanism of the fusion is still uncertain.

Case description

A 9-year-old female child reported with a chief complaint of pain in the right lower back tooth for the past 10 days. The presence of a single maxillary central incisor was an incidental finding. Then a detailed history and multidisciplinary evaluations revealed the diagnosis of SMMCI syndrome.

Conclusion

The effort in diagnosing and managing this syndrome had a strong impact on the child's life of which the parent was highly motivated and got a better understanding of associated problems of overall development.

Clinical significance

In SMMCI syndrome, the patient requires a multidisciplinary health team in order to improve their quality of life. It is of greater importance to diagnose the syndrome and treatment of these median line deformities.

How to cite this article

Balasubramanian S, Haridoss S, Swaminathan K. Solitary Median Maxillary Central Incisor Syndrome: A Case Report. Int J Clin Pediatr Dent 2022;15(4):458-461.

Dental Caries Experience among Children and Adolescents with Cleft Lip and/or Palate: An Umbrella Review

Aim and objective

To assess the systematic reviews and meta-analyses investigating the dental caries experience in children with cleft lip and/or palate (CL/P).

Study design and methodology

A systematic search was carried out from MEDLINE Via PubMed, JBI Database of Systematic Reviews and Implementation Reports, EMBASE, OVID, Cochrane Database of Systematic Review, and Epistemonikos databases. Two independent reviewers carried out the collection and analysis of the study data. Methodological quality was assessed by ROBIS (Risk of bias assessment in systematic review) tool.

Review results

An initial search of electronic databases yielded a total of 25 relevant reviews, of which only three systematic reviews were taken into consideration for qualitative synthesis. The total number of unique primary studies among the three included systematic reviews were 25, of which overlap of the studies was calculated using citation matrix. The corrected covered area (CCA) was estimated to be 0.26. Based on the ROBIS tool, only one systematic review reported with low risk of bias.

Conclusion

Individuals with CL/P report more decayed, missing, or filled teeth/surfaces than those without CL/P in primary, mixed, and permanent dentition. Future studies should focus on the factors which could modify the caries risk of an individual with CL/P.

Clinical significance

This umbrella review offers a more reliable and balanced view regarding the dental caries experience among individuals with cleft lip and/or palate. This paper also highlights the important role of pediatric dentist in multidisciplinary health care team in implementing first dental visit and anticipatory guidance to consider early diagnosis and specific preventive interventions for Early Childhood Caries (ECC) in individuals with CL/P.

How to cite this article

Abirami S, Panchanadikar NT, Muthu MS, et al. Dental Caries Experience among Children and Adolescents with Cleft Lip and/or Palate: An Umbrella Review. Int J Clin Pediatr Dent 2022;15(S-2):S261-S268.

Transportation and Centering Ability of Kedo-S Pediatric and Mtwo Instruments in Primary Teeth: A Cone-beam Computed Tomography Study

Background

Cleaning and debriding the canals and preserving the shape of the canal without deformation is the primary goals of pulpectomy. Transportation is a critical endodontic iatrogenic fault that could cause a catastrophe. This study evaluated the canal centering ability and canal transportation caused by Kedo-S pediatric and Mtwo instruments, using a cone-beam computed tomography (CBCT).

Materials and methods

This in vitro study was performed on distal roots of 50 primary mandibular first molars. The teeth were scanned using CBCT and randomly divided into two groups. The canals were then prepared using either Kedo-S or Mtwo files (n = 25). The instrumented canals were rescanned. The scanned volumes were sectioned at 2, 4, and 6 mm from cementoenamel junction (CEJ). Canal transportation (CT) and instrument centering ability were estimated and compared in both groups.

Results

The mean values for two study groups were compared. T -test was used to determine theP value. The Levene's test was used to test the significance between two groups. The two groups showed similar results in terms of transportation and centering ability (P > 0.05).

Conclusion

Kedo-S pediatric and Mtwo instruments demonstrated similar canal centering ability and CTs.

How to cite this article

Haridoss S, Rakkesh KM, Swaminathan K. Transportation and Centering Ability of Kedo-S Pediatric and Mtwo Instruments in Primary Teeth: A Cone-beam Computed Tomography Study. Int J Clin Pediatr Dent 2022;15(S-1):S30-S34.

Computed Tomographic Assessment of Remaining Dentin and Risk of Perforation after Kedo-S and Mtwo Rotary Instrumentation in Root Canals of Primary Teeth: An In Vitro Study

Background

Root canal cleaning is a key step in the endodontic treatment of the primary molars. An innovative generation of endodontic instruments has been devised with the aim of emerging better procedures. The objective of the study is to assess the preparation of time, the risk of lateral perforation, and the removal of dentin from Kedo-S and Mtwo rotary instruments on primary teeth.

Study design

This is an in vitro experimental study comparing the two groups.

Materials and methods

A total of 50 extracted mandibular primary first molars are collected, divided randomly into two groups of 25 teeth each. Group I: Kedo-S Pediatric rotary file, Group II: Mtwo rotary file. Distal canal is standardized for evaluation and teeth are sectioned at the CEJ. The teeth were instrumented according to manufacturer's guideline. Both the groups are scanned before and after instrumentation of the canal using cone-beam computed tomography (CBCT) and values are evaluated.

Results

Compared with Mtwo files, Kedo-S files need less instrumentation time and limited lateral perforation. No statistical differences were reported between the instrumentation of Kedo-S and Mtwo with regard to the amount of dentin removed.

Conclusion

In pediatric endodontics, Kedo-S pediatric rotary file can be considered an effective alternative to traditional rotary files because it requires less instrumentation time and preserves dentin thickness.

How to cite this article

Swaminathan K, Rakkesh KM, Haridoss S. Computed Tomographic Assessment of Remaining Dentin and Risk of Perforation after Kedo-S and Mtwo Rotary Instrumentation in Root Canals of Primary Teeth: An In Vitro Study. Int J Clin Pediatr Dent 2022;15(S-1):S87-S91.

Individualization of exosuit assistance based on measured muscle dynamics during versatile walking

Variability in human walking depends on individual physiology, environment, and walking task. Consequently, in the field of wearable robotics, there is a clear need for customizing assistance to the user and task. Here, we developed a muscle-based assistance (MBA) strategy wherein exosuit assistance was derived from direct measurements of individuals’ muscle dynamics during specific tasks. We recorded individuals’ soleus muscle dynamics using ultrasonographic imaging during multiple walking speeds and inclines. From these prerecorded images, we estimated the force produced by the soleus through inefficient concentric contraction and designed the exosuit assistance profile to be proportional to that estimated force. We evaluated this approach with a bilateral ankle exosuit at each measured walking task. Compared with not wearing a device, the MBA ankle exosuit significantly reduced metabolic demand by an average of 15.9, 9.7, and 8.9% for level walking at 1.25, 1.5, and 1.75 meters second−1, respectively, and 7.8% at 1.25 meters second−1 at 5.71° incline while applying lower assistance levels than in existing literature. In an additional study (n = 2), we showed for multiple walking tasks that the MBA profile outperforms other bioinspired strategies and the average profile from a previous optimization study. Last, we show the feasibility of online assistance generation in a mobile version for overground outdoor walking. This muscle-based approach enables relatively rapid (~10 seconds) generation of individualized low-force assistance profiles that provide metabolic benefit. This approach may help support the adoption of wearable robotics in real-world, dynamic locomotor tasks by enabling comfortable, tailored, and adaptive assistance.

Impact of Pediatric Dentistry Residents Posted in Pediatrics Department: A Retrospective Assessment of 6 Years

Aim

To measure the influence of rotatory pediatrics postings for dental residents on the outpatient census of the pediatric dentistry department. The secondary aims were to assess the change in trend toward the number of preschool children visiting the department before and after the initiation of pediatrics posting and also to find the percentage of children affected with caries among children visiting the pediatricians.

Materials and methods

Retrospectively, the census of the pediatric dentistry department was calculated from 2010 to 2016. The number of preschool children who visited the pediatric dentistry department during this period was determined. From the pediatrics posting records, the dental status of the children, the number screened, the number referred, and the number reported to dentistry following referral were tabulated. Descriptive statistics and Chi-square tests were performed.

Results

After the initiation of pediatrics postings for residents, the outpatient census has increased by 26%. There was a significant increase in the number of preschool children visiting the pediatric dentist. About 57.09% of children screened in the pediatrics department had dental disease.

Conclusion

There is an increase in the patient flow of the pediatric dentistry department with a greater number of preschool children visiting the pediatric dentist after initiation of the pediatrics postings for residents. More than half the children visiting pediatricians had dental disease requiring professional care.

Clinical significance

Pediatrics postings for residents can be used in teaching centers as an opportunity to spread awareness and increase the number of preschool children visiting pediatric dentists, thereby increasing prevention and early intervention of early childhood caries.

How to cite this article

Mohan A, Muthu MS, Ramachandran P, et al. Impact of Pediatric Dentistry Residents Posted in Pediatrics Department: A Retrospective Assessment of 6 Years. Int J Clin Pediatr Dent 2021;14(1):84–87.

Correlation Between Body Mass Index and Dental Caries Among Three- to 12-Year-Old Schoolchildren in India: A Cross-Sectional Study

Introduction: Diet is a deeply ingrained element of a person’s life. Children’s dietary habits are a significant contributor to obesity and dental caries. Dental caries during childhood continues to be a significant public health concern, while childhood obesity is increasingly being cited as a major public health problem. This study aimed to assess the correlation between body mass index (BMI) and dental caries in children aged three to 12 years who attended both government and private schools in Chennai, Tamil Nadu, India.

Materials and methods: We conducted a cross-sectional review of 2200 children aged three to 12 years with clinically recorded dental caries. The World Health Organization diagnostic criteria for BMI percentile was used to evaluate and record dental caries clinically. The Mann-Whitney and the Kruskal-Wallis tests were used for univariate comparisons.

Results: Mean values between the overweight category and underweight category revealed no significant differences.

Conclusion: We found no association between BMI-for-age and dental caries in children in both primary and mixed dentition. This relationship should be investigated further by longitudinal studies.

Do Oral Health Educational Programmes for Expectant Mothers Prevent Early Childhood Caries? - Systematic Review

PURPOSE

To summarise the evidence for the efficacy of oral health educational programmes provided to expectant mothers for preventing Early Childhood Caries (ECC) and to determine the most effective intervention programme.

MATERIALS AND METHODS

The search strategy included clinical trials in the Cochrane Oral Health Group's Trials Register, PubMed, Science Direct, Google Scholar, LILACS and ClinicalKey (up to 26 August 2013) in English. Reference lists of identified randomised controlled trials (RCTs) and review articles were also hand searched. Studies were selected according to predefined inclusion and exclusion criteria.

RESULTS

The search identified 392 studies, only four of which were included. Risk ratios (RR) were calculated. The quality of the evidence was assessed by the GRADE approach. Results showed statistically significant decreases in caries incidence (RR = 0.18, 95% CI [from 0.06 to 0.52]) in one study. Meta-analysis could not be performed.

CONCLUSION

Oral health educational programmes for expectant mothers may have a positive impact in preventing ECC, although the evidence is weak.

Prevalence and pattern of early childhood caries in a rural South Indian population evaluated by ICDAS with suggestions for enhancement of ICDAS software tool

BACKGROUND

Early Childhood Caries (ECC) continues to be the most common public health issue in developing countries.

AIM

The purpose of this study was to assess the prevalence of ECC in 0- to 3-year-old children from rural areas of South India, using the ICDAS.

DESIGN

A cross-sectional study was carried out with 1486 children aged 0-3 years in South India. Two calibrated examiners performed the oral examinations using International Caries Detection and Assessment System (ICDAS) criteria. Data analysis involved the use of the new ICDAS epidemiological software tool.

RESULTS

Prevalence of ECC in studied child population was 40.6%. Among the 604 children with ECC, only non-cavitated teeth were present in 314 children, and only cavitated teeth were present in 84 children. The remaining 206 children had both cavitated and non-cavitated teeth. Interesting lesion behavior was observed in 27 children, who had enamel lesions in mandibular canines only, in an otherwise sound dentition. On examining the teeth surfaces affected (n = 102,274), 50.3% had non-cavitated surfaces and 49.7% had cavitated surfaces.

CONCLUSIONS

The results demonstrate the high prevalence of ECC in this population and the need to consider early diagnosis and specific preventive interventions. The authors of this study have also addressed their views about the use of ICDAS software tool.

Crystal structures of two new carbazole derivatives: 12-(4-nitrophenyl)-7-phenylsulfonyl-7H-benzofuro[2,3-b]carbazole and 2-methyl-4-(4-nitrophenyl)-9-phenylsulfonyl-9H-thieno[2,3-b]carbazole

The title compounds are carbazole derivatives, with a benzo­furan ring system in (I) and a methyl­thio­phene ring in (II) fused with the respective carbazole moiety. In the crystals of both compounds, mol­ecules are linked via C—H⋯O hydrogen bonds, forming sheets lying parallel to (10).

The title compounds, C₃₀H₁₈N₂O₅S, (I), and C₂₇H₁₈N₂O₄S₂, (II), are carbazole derivatives with a phenyl­sulfonyl group and a nitro­phenyl group attached to the carbazole moiety in identical positions in both mol­ecules. A benzo­furan ring system in (I) and a methyl­thio­phene ring in (II) are fused with the respective carbazole moieties on the same sides. The mean plane of the carbazole ring system makes a dihedral angle of 3.17 (7)° with the benzo­furan ring system in (I) and a dihedral angle of 3.39 (11)° with the methyl­thio­phene ring in (II), implying that both fused units are essentially planar. The mean planes of the carbazole ring systems in both the compounds are almost orthogonal to the respective nitro-substituted phenyl rings, making dihedral angles of 75.64 (10) and 77.63 (12)° in compounds (I) and (II), respectively. In (I), the phenyl­sulfonyl ring system is positionally disordered with a refined occupancy ratio of 0.63 (2):0.37 (2). In both compounds, the mol­ecular structures are stabilized by intra­molecular C—H⋯O hydrogen bonds, generating S(6) ring motifs with the sulfone group O atoms. In the crystal of compound (I), mol­ecules are linked by pairs of C—H⋯O hydrogen bonds, which generate R₂²(18) inversion dimers, and inter­connected by C(14) chains running along the c-axis direction, whereas in compound (II), the C—H⋯O hydrogen bonds generate R₄³(37) ring motifs. In the crystals of both compounds, C—H⋯O hydrogen-bonded sheets are formed lying parallel to (10-1). In addition, C—H⋯π and offset π–π inter­actions [inter­centroid distance = 3.7158 (14) Å in (I) and 3.9040 (15) Å in (II)] are also present in the crystals of both compounds.

Sudden cardiac death in South India: Incidence, risk factors and pathology

BACKGROUND

Sudden cardiac death (SCD) is a major cause of mortality secondary to coronary artery disease (CAD) in the industrialized societies. Although South Asians have a high prevalence of CAD, the frequency and underlying pathology of SCD among this population are unknown.

METHODS

Medical records of consecutive patients presenting with unexplained sudden death (USD) in a tertiary care center were reviewed. Patients with trauma, violent deaths, positive toxicology and non-cardiac pathology were excluded to determine sudden cardiac death (SCD). Cardiac pathological findings were analyzed by autopsy. SCD rate was estimated based on census and government vital statistics for the years studied.

RESULTS

During a two year period, 223 patients (mean age 55 + 10 yrs, 78.9% male, body mass index 26 + 4, 60% smokers, 39% known CAD, 46% hypertension, 43% diabetes) presented to hospital with USD. SCD was attributed to myocardial infarction (MI) in 87% of cases; 69% were acute (96% anterior MI); 76% were small/moderate infarct and 9.9% of the cohort had normal hearts. Based on official municipal vital statistics, the SCD rate in those >35 yrs of age was estimated as 39.7/100,000 with male/female ratio of 4.6.

CONCLUSIONS

SCD in this south Indian city occurred predominantly in men of relatively young age and was most frequently associated with small or moderate-sized acute MI. Improved health care access, preventive measures and enhanced emergency management may reduce SCD from acute MI in this locale.

Crystal structures and conformational analyses of three pyranochromene derivatives

The title compounds, C27H20O6, (I) [systematic name: methyl 7-oxo-14-phenyl-1H,7H,14H-pyrano[3,2-c:5,4-c']dichromene-14a(6bH)-carboxyl-ate], C24H22O5, (II) [systematic name: methyl 1-oxo-6-phenyl-2,3,4,12b-tetra-hydro-1H,6H-chromeno[3,4-c]chromene-6a(7H)-carboxyl-ate], and C25H23N3O4, (III) [systematic name: 6-(4-ethyl-phen-yl)-2,4-dimethyl-1,3-dioxo-2,3,4,12b-tetra-hydro-1H,6H-chromeno[4',3':4,5]pyrano[2,3-d]pyrimidine-6a(7H)-carbo-nitrile], are pyran-ochromene derivatives. The central pyran rings (B) of compounds (I) and (III) adopt half-chair conformations, whereas that of compound (II) adopts a sofa conformation. The pyran rings (A) of the chromene ring systems of compounds (II) and (III) adopt half-chair conformations, while that of compound (I) adopts a sofa conformation. The mean plane of the central pyran rings (B) make dihedral angles of 70.02 (6), 61.52 (6) and 69.12 (7)°, respectively, with the mean planes of the chromene moieties (C+A) of compounds (I), (II) and (III). The bicyclic coumarin ring system (C+A+B+E) in compound (I) is almost planar (r.m.s. deviation = 0.042 Å). The carbo-nitrile side chain in compound (III) is very nearly linear, with the C-C N angle being 176.6 (2)°. The cyclo-hexene ring (E), fused with the central pyran ring (B) in compound (II) adopts a sofa conformation. In the mol-ecular structures of compounds (II) and (III), there are C-H⋯O short contacts, which generate S(7) ring motifs. In the crystal structures of the title compounds, mol-ecules are linked by C-H⋯O hydrogen bonds, which generate mol-ecular sheets parallel to the ab plane, with R 4 (3)(28) loops in (I), inversion dimers with R 2 (2)(10) loops in (II) and chains along [010] with R 2 (2)(12) ring motifs in (III). In the crystal structures of (I) and (III), there are also C-H⋯π inter-actions present, leading to the formation of a three-dimensional framework in (II) and to sheets parallel to (101) in (III).

Evaluation of canal transportation and centering ability of K 3 (0.02%) and K 3 (0.04%) with hand K files in primary teeth using spiral computed tomography

BACKGROUND

One of the objectives of root canal preparation is to clean and shape the root canal system while maintaining the original configuration. Therefore, it is important to keep the instruments centered to provide a correct enlargement, without excessive weakening of the root structure.

AIM

The aim of the study was to compare canal transportation and centering ability of K 3 (0.02% taper) and K 3 (0.04% taper) with stainless steel hand K files in primary teeth using a spiral computed tomography (SCT) scan.

MATERIALS AND METHODS

A total of 75 extracted mandibular primary second molars was collected. Canals were divided randomly into three groups of 25 teeth each. Group I: K 3 files (0.02% taper), Group II: K 3 (0.04% taper), and Group III: Stainless steel hand K files. Three regions from apical, mid-root, and coronal levels of the canal were recorded. All the teeth were scanned before and after instrumentation by using SCT.

RESULTS

K 3 (0.02% taper) showed less canal transportation and a better centering ratio than K 3 (0.04% taper) and stainless steel hand K files.

STATISTICAL ANALYSIS

The mean values were compared between different study groups and the P-value was calculated by using Kruskal-Wallis one-way ANOVA. The Mann-Whitney U-test followed by the Bonferroni correction method was employed to identify the significant groups at the 5% level.

CONCLUSION

K 3 (0.02% taper) shaped root canals without significant shaping errors when compared to K 3 (0.04% taper) and stainless steel hand K files in primary teeth.

Modulation of GSH with exogenous agents leads to changes in glyoxalase 1 enzyme activity in VL-17A cells exposed to chronic alcohol plus high glucose

Gluthathione (GSH) is a major cellular antioxidant. The present study utilizing VL-17A cells exposed to chronic alcohol plus high glucose investigated the changes in oxidative stress, toxicity, and glyoxalase 1 activity as a detoxification pathway due to changes in GSH level through GSH supplementation with N-acetyl cysteine (NAC) or ursodeoxycholic acid (UDCA) and its depletion through buthionine sulfoximine (BSO) or diethyl maleate (DEM). Glyoxalase 1 plays an important role in detoxification of methylglyoxal which is formed as a precursor of advanced glycated end products formed due to high glucose mediated oxidative stress. Significant changes in glyoxalase 1 activity utilizing methylglyoxal or glyoxal as substrates occurred with NAC or UDCA or BSO or DEM supplementation in chronic alcohol plus high glucose treated VL-17A cells. NAC or UDCA administration in chronic alcohol plus high glucose treated VL-17A cells increased viability and decreased ROS levels, lipid peroxidation and 3-nitrotyrosine adduct formation. Similarly, GSH depletion with BSO or DEM had an opposite effect on the parameters in chronic alcohol plus high glucose treated VL-17A cells. In conclusion, modulation of GSH with NAC or UDCA or BSO or DEM leads to significant changes in oxidative stress, glyoxalase 1 enzyme activity and toxicity in chronic alcohol plus high glucose treated VL-17A cells.

Relapsing Guillain-Barre syndrome in pregnancy and postpartum

Guillain-Barre syndrome (GBS) rarely complicates pregnancy, but can be associated with high maternal and perinatal morbidity if not properly identified and treated. A high index of suspicion, supportive measures, access to intensive care unit and intravenous immunoglobulin (IVIG) therapy are cornerstones of management in GBS complicating pregnancy. Neurologists and Obstetricians should be aware of the risks of relapsing GBS in the immediate postpartum period. Surgery and anesthesia may be triggers for relapse in association with an overall increase in pro-inflammatory cytokines in the postpartum period. We report a unique case of GBS complicating pregnancy in the third trimester followed by a relapse in the postpartum period. She made a good recovery with supportive measures and a repeat course of IVIG during the relapse.

Single-rooted primary first mandibular molar

Morphological variations like single-rooted molar in primary dentition are scarce. Understanding the root canal anatomy and variations is necessary for successful root canal therapy. The purpose of the present article is to report successful endodontic treatment of primary left mandibular first molar with an abnormal morphology of a single root. This case report highlights the importance of knowledge and its applications in the management of anomalous anatomic variants which play a crucial role in the success of endodontic treatment.

GSH protects against oxidative stress and toxicity in VL-17A cells exposed to high glucose

PURPOSE

The deficiency of glutathione (GSH) has been linked to several diseases. The study investigated the role of GSH as a protective factor against hyperglycemia-mediated injury in VL-17A cells treated with 50 mM glucose.

METHODS

The cell viability and different oxidative stress parameters including glyoxalase I activity were measured.

RESULTS

GSH supplementation with 2 mM N-acetyl cysteine (NAC) or 0.1 mM ursodeoxycholic acid (UDCA) increased the viability, GSH level and the GSH-dependent glyoxalase I activity in 50 mM glucose-treated VL-17A cells. Further, pretreatment of 50 mM glucose-treated VL-17A cells with NAC or UDCA decreased oxidative stress (levels of reactive oxygen species and protein carbonylation), apoptosis (caspase 3 activity and annexin V-propidium iodide positive cells) and glutathionylated protein formation, a measure of oxidative stress. GSH depletion with 0.4 mM buthionine sulfoximine (BSO) or 1 mM diethyl maleate (DEM) potentiated the decrease in viability, glyoxalase I activity and increase in oxidative stress and apoptosis, with decreased GSH levels in 50 mM glucose-treated VL-17A cells.

CONCLUSION

Thus, changes in GSH levels with exogenous agents such as NAC, UDCA, BSO or DEM modulate hyperglycemia-mediated injury in a cell model of VL-17A liver cells.

Pesticides and human diabetes: a link worth exploring?

It is no exaggeration to claim that the 'diabetes epidemic' has become a 'runaway train' causing huge health and economic consequences, especially in the developing nations. Traditionally, the risk factors for diabetes have largely focused on genetics and lifestyle. Great emphasis is placed on lifestyle measures and finding novel pharmacological treatment options to combat diabetes, but there is increasing evidence linking environmental pollutants, especially pesticides, to the development of insulin resistance and Type 2 diabetes. Pesticide use has increased dramatically worldwide and the effects of pesticides on glucose metabolism are too significant for a possible diabetogenic link to be dismissed. The aim of this review article was to assess the links between pesticides and human diabetes with the goal of stimulating further research in this area.

Feasibility studies for production of 89Sr in the Fast Breeder Test Reactor (FBTR)

89Sr, a pure beta emitter with half life of 50.53 d is used as its chloride solution for palliative care of bone metastases. This paper describes the feasibility studies that have been conducted at FBTR, IGCAR for production of this radionuclide using the 89Y(n, p)89Sr reaction. Yttria pellets were irradiated in a special subassembly at the core centre for a total of 73 d in two steps of 35 d and 38 d with a time gap of 38 d. The irradiated yttria target was dissolved in nitric acid and the bulk Y was separated by solvent extraction using the TBP-HNO3 complex. The 89Sr fraction was purified using the cation exchange resin DOWEX 50W×8 (100-200 mesh size) from the other radioactive impurities seen. The eluted 89Sr fraction was assayed using a GM counting system. The 89Sr activity produced in 1 g of yttria pellet was found to be 19 mCi.

Methyl (2Z)-2-bromomethyl-3-(3-chlorophenyl)prop-2-enoate

There are two independent mol­ecules (A and B) in the asymmetric unit of the title compound C₁₁H₁₀BrClO₂, which represents the Z isomer. The methyl­acrylate moieties are essentially planar, within 0.084 (2) and 0.027 (5) Å in mol­ecules A and B, respectively. The benzene ring makes dihedral angles of 13.17 (7) and 27.89 (9)° with the methyl­acrylate moiety in mol­ecules A and B, respectively. The methyl­bromide moiety is almost orthogonal to the benzene ring, making dihedral angles of 81.46 (16)° in mol­ecule A and 79.61 (16)° in mol­ecule B. The methyl­acrylate moiety exhibits an extended trans conformation in both mol­ecules. In the crystal, pairs of C—H⋯O hydrogen bonds result in the formation of quasi-centrosymmetric R₂²(14) AB dimers.

Methyl (2Z)-2-bromomethyl-3-(2,4-dichlorophenyl)prop-2-enoate

In the title compound C₁₁H₉BrCl₂O₂, which represents the Z isomer, the methyl­acrylate moiety is essentially planar within 0.039 (2) Å and has an extended trans configuration. The benzene ring makes a dihedral angle of 28.3 (1)° with the mean plane of the methyl­acrylate moiety. The crystal packing is characterized by C—H⋯O hydrogen bonding and halogen–halogen inter­actions [Cl⋯Cl = 3.486 (3) Å], resulting in the formation of R₂²(11) ring motifs and connecting the mol­ecules into chains propagating along the b axis.

Inhibition of CYP2E1 leads to decreased malondialdehyde-acetaldehyde adduct formation in VL-17A cells under chronic alcohol exposure

AIM

Ethanol metabolism leads to the formation of acetaldehyde and malondialdehyde. Acetaldehyde and malondialdehyde can together form malondialdehyde-acetaldehyde (MAA) adducts. The role of alcohol dehydrogenase (ADH) and cytochrome P4502E1 (CYP2E1) in the formation of MAA-adducts in liver cells has been investigated.

MAIN METHODS

Chronic ethanol treated VL-17A cells over-expressing ADH and CYP2E1 were pretreated with the specific CYP2E1 inhibitor - diallyl sulfide or ADH inhibitor - pyrazole or ADH and CYP2E1 inhibitor - 4-methyl pyrazole. Malondialdehyde, acetaldehyde or MAA-adduct formation was measured along with assays for viability, oxidative stress and apoptosis.

KEY FINDINGS

Inhibition of CYP2E1 with 10 μM diallyl sulfide or ADH with 2mM pyrazole or ADH and CYP2E1 with 5mM 4-methyl pyrazole led to decreased oxidative stress and toxicity in chronic ethanol (100 mM) treated VL-17A cells. In vitro incubation of VL-17A cell lysates with acetaldehyde and malondialdehyde generated through ethanol led to increased acetaldehyde (AA)-, malondialdehyde (MDA)-, and MAA-adduct formation. Specific inhibition of CYP2E1 or ADH and the combined inhibition of ADH and CYP2E1 greatly decreased the formation of the protein aldehyde adducts. Specific inhibition of CYP2E1 led to the greatest decrease in oxidative stress, toxicity and protein aldehyde adduct formation, implicating that CYP2E1 accelerates the formation of protein aldehyde adducts which can be an important mechanism for alcohol mediated liver injury.

SIGNIFICANCE

CYP2E1-mediated metabolism of ethanol leads to increased AA-, MDA-, and MAA-adduct formation in liver cells which may aggravate liver injury.