Role of pressmud compost for reducing toxic metals availability and improving plant growth in polluted soil: Challenges and recommendations.

Pressmud compost is an organic soil amendment and a robust technology that has potential to restore toxic metals (TMs) polluted soil. The application of organic amendments including pressmud compost in soil for toxic metals (TMs) alleviation have gained considerable attention as compared to traditional methods among the scientific community. In this review paper, we summarized the literature aiming to understand the immobilization efficacy of TMs such as cadmium, lead, chromium, copper, nickel, iron, zinc, and manganese, underlying mechanisms, plant growth, essential nutrients and soil health under pot, field and incubation conditions which has not been well investigated up-to-date. The application of pressmud compost at 10 t ha-1 rate has shown highly potential to reduce the bioavailability and bioaccumulation of TMs in the polluted soil. The immobilization mechanism of TMs in soil depends on soil pH, soil type, cation exchange capacity, hydraulic conditions, nutrients dynamics and soil properties. The application of pressmud compost integrated with biochar, compost, rock phosphate, farmyard manure, bagasse ash, molasses immobilized the cadmium, lead, copper, chromium, nickel and zinc in alkaline polluted soil, whereas pressmud compost combined with poultry manure and farmyard manure increased the bioavailability of lead, cadmium, cobalt, chromium, copper, zinc, iron and manganese in acidic soil, it could be due to aging of pressmud compost, application rate, metal type, nature of soil, particle size, application method, plant type and agronomic practices. There is a lack of knowledge on the phyto-management of arsenic, mercury and boron in soil amended with pressmud compost. Future studies must be focused on potential of pressmud compost co-amended with minerals, modified biochars and nano-material for immobilization of TMs in polluted soil-plant through machine learning/artificial intelligence in order to reduce the health risks and improve public health safety in urban and rural areas.

Comparative role of charcoal, biochar, hydrochar and modified biochar on bioavailability of heavy metal(loid)s and machine learning regression analysis in alkaline polluted soil.

Pot experiment was performed aimed to assess the comparative role of charcoal, biochar, hydrochar and thiourea-vegetable modified biochar at 1 and 2 % doses, and <1 mm particle size on the bioavailability of Cd, Pb, As, Ni, Cu and Zn, and enhance NPK, and mustard growth in a slightly alkaline polluted soil. Furthermore, machine learning method was used to examine the systematic evaluation of the impact of feature selection based on Pearson's correlation on the performance of the linear regression model. The results revealed that maximum fresh and dry biomass of mustard was observed by 26.38 and 38.18 % with hydrochar 1 %, whereas lemon biochar at 2 % reduced fresh and dry biomass up to 34.0 and 53.0 % than control. The immobilization of Cd and Pb was observed by 83.70 and 71.15 % with thiourea-vegetable modified biochar at 2 %, As 71.62 % with hydrochar 2 %, Ni 80.84 % with thiourea-vegetable modified biochar 2 %, Cu 66.32 % with and Zn 36.30 % with thiourea-vegetable modified biochar at 2 % than control. However, the maximum mobilization of Cu in soil was observed by 30.3 % with lemon biochar 2 %, similarly for Zn 37.36 % with hydrochar 2 % as compared with other treatments. The phyto-availability of Cd, Pb, As and Cu in the mustard shoot and root biomass was reduced except Ni and Zn in soil than control. It was observed that using the machine learning regression analysis approach, variability in treatments effectiveness is evident across different feature correlation thresholds. This study clearly shows that the beneficial role of studied amendments on mustard growth and reduced bioavailability of heavy metal(loid)s and enhance primary macronutrients in alkaline polluted soil. It is suggested that future studies may be conducted on combined application of studies amendments on plant growth, immobilization of heavy metal(loid)s in multi-metal polluted soil under different field conditions.

Diagnosis and evaluation of Crouzon syndrome.

Crouzon syndrome is an autosomal dominant condition characterized by craniosynostosis with associated dentofacial anomalies. This report describes the different clinical features in two affected individuals of different families with particular reference to characteristic findings of this syndrome.

Effectiveness of electric toothbrush as vibration method on orthodontic tooth movement: a split-mouth study.

OBJECTIVE: To investigate the effects of application of vibratory stimuli, using an electric toothbrush, on the rate of orthodontic tooth movement during maxillary canine retraction. METHODS: A split-mouth study was conducted in 28 subjects (mean age = 20.8 years; ranging from 18 to 24 years) whose bilateral maxillary first premolars were extracted with subsequent canine retraction. On the Vibration side, light force (100 g) was applied to the canine for 90 days, in combination with vibratory stimuli provided by an electric toothbrush; only orthodontic force was applied to the canine on the non-vibration side. Amount of canine movement was measured monthly. Related to electronic toothbrush usage, a diary was provided to each patient for recording discomfort during experimental period, having 100-mm visual analogue scale (VAS). The paired t-test was used to assess the differences in amount of tooth movement between canines of the vibration and non-vibration sides. RESULTS: The amount of tooth movement was similar for canines on the vibration side and on the non-vibration side (mean 0.81 ± 0.10 mm and 0.82 ± 0.11 mm, respectively, p> 0.05). Plaque accumulation was minimal in any subject throughout the study. No subject reported discomfort as a result of using the electric toothbrush. CONCLUSIONS: This study demonstrates that application of vibratory stimuli using an electric toothbrush, in combination with light orthodontic force, do not accelerate orthodontic tooth movement.

Investigation of transmigrated mandibular canines.

INTRODUCTION: Canine transmigration is a rare orthodontic condition and it is relevant to perform the proper diagnose at an early age. OBJECTIVE: The aim of the current study was to find out the frequency of transmigrated mandibular canines (TRC) in orthodontic patients obtained from South Asian population of Pakistan origin. METHODS: Panoramic radiographs of 2,550 untreated orthodontic patients (1,248 males; 1,302 females) were included, to investigate the presence, site, and type of TRC. Any permanent mandibular canine that was found to be crossing the midline in panoramic radiographs was considered as TRC. RESULTS: The frequency of TRC was found to be 0.98%. TRC were only found unilaterally. No significance regarding gender and side was found. Nineteen TRC displayed a type 1 transmigratory pattern, while type 2 and type 5 transmigratory patterns were encountered in three patients. CONCLUSION: Frequency of transmigrated mandibular canines in the studied sample was 0.98%.

Leveling curve of Spee and its effect on mandibular arch length.

OBJECTIVE: To determine the additional space required for leveling of curve of Spee in the mandibular arch by continuous arch wire mechanics. STUDY DESIGN: Quasi-experimental interventional. SETTING: Orthodontics Department, Karachi Medical and Dental College from September 2002 to September 2004. SUBJECTS AND METHODS: Depth of curve of Spee and arch length were measured on 40 pre-treatment and posttreatment plaster models with the help of sharpened Boley gauge. RESULT: The study showed that clinical practice of allowing 1 mm of arch circumference for leveling each millimeter of curve of Spee overestimates the amount of arch space needed to flatten the curve of Spee (p < 0.001). CONCLUSION: The result suggested that the belief that 1 mm of arch circumference was necessary to level each millimeter of curve of spee present was an overestimation.

Comparison of condylar positions in centric relation and centric occlusion in pre-treatment malocclusion cases.

OBJECTIVE: To compare the centric relation-centric occlusion discrepancy in Angle's class II and class III with Angle's class I malocclusion cases in sagittal (antero-posterior) plane as determined by the difference in the overjet. DESIGN: Comparative; cross-sectional study. PLACE AND DURATION OF STUDY: Orthodontic Outpatient Department, Karachi Medical and Dental College, from June 2003-August 2004. PATIENTS AND METHODS: Patients were divided into 3 groups according to the Angle's classification. Leaf gauges were employed for muscle deprogramming. Bimanual manipulation technique was used to guide the mandible in to centric relation. Softened red modeling wax was used to obtain the centric bite registration. The study casts were trimmed in centric relation using bite registration. Overjet was recorded in centric relation and centric occlusion by dial caliper on casts. RESULTS: The overjet values for centric relation-centric occlusion discrepancy were highly significant for Angle's class II (p-value 0.002) and Angle's class III (p-value 0.005) when compared with Angle's class I malocclusion. CONCLUSION: Centric relation-centric occlusion discrepancy can occur in any dental class regardless of age and gender. However, especial emphasis should be given to Angle's class II and III (with functional shift) cases when evaluating any orthodontic patient.

Relation between centric slide and Angle's classification.

OBJECTIVE: To compare the difference in sagittal cephalometric analysis in centric occlusion (CO) and in centric relation (CR), among Angle's classes i.e. class I, class II, and class III. DESIGN: Comparative, cross-sectional study. PLACE AND DURATION OF STUDY: Orthodontic Outpatient Department, Karachi Medical and Dental College, Karachi, from July 2003 to December 2004. PATIENTS AND METHODS: Eighty pre-treatment orthodontic patients were divided into 3 groups according to Angle's classification. The first lateral cephalogram was taken in CO. Then leaf gauges were placed in between incisors for deprogramming. The second cephalogram was taken with leaf gauges in place to obtain centric relation. Both the radiographs were traced. Angle ANB was measured for sagittal analysis. ANB angle compares the position of mandible with the maxilla relating it with the cranial base. Angles from both cephalograms were compared with each other. RESULTS: Significant difference (p<0.0001) was found in values of ANB in CO (2.93 degrees -/+3.7) and CR (4.88 degrees -/+3.4) cephalograms. Significant CO-CR discrepancy was found (p<0.05) in Angle's class III patients (3.05 degrees -/+0.55) in comparison to Angle's class I (1.96 degrees -/+0.94) and class II (1.65 degrees -/+0.65). CONCLUSION: CO-CR discrepancy can occur regardless of Angle's classification. Special emphasis should be given to Angle's class III patients for the centric slide.

Effectiveness of electric toothbrush as vibration method on orthodontic tooth movement: a split-mouth study

Abstract Objective: To investigate the effects of application of vibratory stimuli, using an electric toothbrush, on the rate of orthodontic tooth movement during maxillary canine retraction. Methods: A split-mouth study was conducted in 28 subjects (mean age = 20.8 years; ranging from 18 to 24 years) whose bilateral maxillary first premolars were extracted with subsequent canine retraction. On the Vibration side, light force (100 g) was applied to the canine for 90 days, in combination with vibratory stimuli provided by an electric toothbrush; only orthodontic force was applied to the canine on the non-vibration side. Amount of canine movement was measured monthly. Related to electronic toothbrush usage, a diary was provided to each patient for recording discomfort during experimental period, having 100-mm visual analogue scale (VAS). The paired t-test was used to assess the differences in amount of tooth movement between canines of the vibration and non-vibration sides. Results: The amount of tooth movement was similar for canines on the vibration side and on the non-vibration side (mean 0.81 ± 0.10 mm and 0.82 ± 0.11 mm, respectively, p> 0.05). Plaque accumulation was minimal in any subject throughout the study. No subject reported discomfort as a result of using the electric toothbrush. Conclusions: This study demonstrates that application of vibratory stimuli using an electric toothbrush, in combination with light orthodontic force, do not accelerate orthodontic tooth movement.

Resumo Objetivo: investigar os efeitos da aplicação de estímulo vibratório, usando escova elétrica, sobre a taxa de movimentação dentária ortodôntica durante a retração dos caninos superiores. Métodos: um estudo de boca-dividida foi realizado em 28 pacientes (idade média de 20,8 anos, variando entre 18 e 24 anos) cujos dois primeiros pré-molares superiores foram extraídos, com subsequente retração dos caninos. No lado Com Vibração, uma força leve (100g) foi aplicada no canino durante 90 dias, em combinação com o estímulo vibratório gerado por uma escova de dentes elétrica; enquanto os caninos do lado Sem Vibração foram submetidos apenas à aplicação da força ortodôntica. A quantidade de movimentação dos caninos foi aferida mensalmente. Quanto ao uso da escova de dentes elétrica, diários foram fornecidos aos pacientes para que esses anotassem, em Escalas Visuais Analógicas (EVA) de 100 mm, o desconforto sentido durante o período experimental. O teste t pareado foi utilizado para avaliar as diferenças na quantidade de movimentação dos caninos nos lados Com Vibração e Sem Vibração. Resultados: os valores da movimentação dentária foram semelhantes nos lados Com Vibração e Sem Vibração (médias de 0,81 ± 0,10 mm e 0,82 ± 0,11 mm, respectivamente, p> 0,05). O acúmulo de placa dentária nos pacientes dessa amostra foi mínimo, ao longo de todo o estudo. Nenhum paciente relatou desconforto durante o uso da escova elétrica. Conclusões: o presente estudo demonstrou que a aplicação de estímulo vibratório usando uma escova elétrica, associada a forças ortodônticas leves, não foi capaz de acelerar a movimentação dentária ortodôntica.

Investigation of transmigrated mandibular canines

ABSTRACT Introduction: Canine transmigration is a rare orthodontic condition and it is relevant to perform the proper diagnose at an early age. Objective: The aim of the current study was to find out the frequency of transmigrated mandibular canines (TRC) in orthodontic patients obtained from South Asian population of Pakistan origin. Methods: Panoramic radiographs of 2,550 untreated orthodontic patients (1,248 males; 1,302 females) were included, to investigate the presence, site, and type of TRC. Any permanent mandibular canine that was found to be crossing the midline in panoramic radiographs was considered as TRC. Results: The frequency of TRC was found to be 0.98%. TRC were only found unilaterally. No significance regarding gender and side was found. Nineteen TRC displayed a type 1 transmigratory pattern, while type 2 and type 5 transmigratory patterns were encountered in three patients. Conclusion: Frequency of transmigrated mandibular canines in the studied sample was 0.98%.

RESUMO Introdução: a transmigração de caninos é uma condição ortodôntica rara, e é importante realizar seu adequado diagnóstico ainda em idade precoce. Objetivo: o objetivo do presente estudo foi avaliar a frequência da transmigração de caninos inferiores (TCI) em pacientes ortodônticos de origem paquistanesa. Métodos: com o objetivo de analisar a presença, o local e o tipo de TCI, foram avaliadas 2.550 radiografias panorâmicas pré-tratamento (1.248 homens, 1.302 mulheres) de pacientes ortodônticos. Foram considerados como TCI os caninos inferiores permanentes que, na radiografia, estivessem cruzando a linha média. Resultados: a frequência de TCI foi de 0,98%. Os achados demonstraram a presença de apenas TCI unilaterais, sem diferenças significativas em relação ao sexo e ao lado da arcada. O tipo 1 de transmigração foi encontrado em 19 pacientes e os tipos 2 e 5, em três pacientes. Conclusão: na presente amostra de origem paquistanesa, a frequência da transmigração de caninos inferiores foi de 0,98%.