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Objective. Bonding failure is a problem in orthodontic therapy and has been associated with orthodontic emergencies and delayed treatment time. The aim of this study is to determine the bracket failure rate among patients undergoing orthodontic therapy. Materials and Methods. From the archives of posttreatment records, 200 total cases were selected, out of which 122 cases had detailed treatment records. Cases with incomplete records, large restorations, or enamel aberrations were excluded from the study. Descriptive statistics were applied to obtain sample characteristics, and a chi-square test was applied to compare the bracket failure between different categories. Result. Out of the 122 samples enrolled in the study, female and male patients comprised 71% and 29%, respectively. Class I malocclusions were the most common problem (56%), followed by Class II (41%) and Class III (3%). The bracket failure rate was 3.43%, and 32% of the patients had an incidence of bracket failure. There was no significant difference in bracket failure among genders (p=0.344), malocclusion types (p=0.191), or operators (p=0.188). The maxillary left quadrant was the most common site of bracket failure, followed by the mandibular right quadrant. Conclusion. Bracket failure is relatively uncommon. It is not affected by the gender or age of the patient or by malocclusion type. The maxillary left and mandibular right quadrants are the most common sites of bracket failure.

Background & Objectives: Mesio-distal tooth size-arch length discrepancy is one of the major sources of malocclusion. Accurate prediction of space required for unerupted tooth can help in early interception of developing malocclusion. Various methods has been proposed for prediction of mesio-distal tooth size however accuracy of such methods in population groups other than that on which these methods are based remains questionable. The aims and objectives of this study were to test the reliability of Moyer’s and Tanaka Johnston mixed dentition analysis in Nepalese population, to construct prediction tables for Nepalese population if these methods were found not reliable.Materials & Methods: Study models of 77 subjects (31 males,46 females) fulfilling the inclusion criteria were retrieved from department archive. Tooth dimensions were measured using electronic digital caliper. Moyer’s and Tanaka and Jhonston methods were applied to predict the mesio- distal tooth size of canines and premolars. The predicted values were compared with the actual mesio-distal mesio-distal size. A regression equation based on actual canine and premolar mesio-distal dimensions and sum of mandibular permanent incisors was also developed.Results: Independent t-test showed that there was no significant difference between mesio-distal tooth size in males and females. Paired t-test showed that there was no difference in mesio-distal tooth size between right and left sides of the arch. Tanaka – Johnston analysis overestimated the mesio-distal size in both males and females. Moyer’s method at 75% overestimated the mesio-distal size in male and female and the difference were statistically significant while at 50% it underestimated the tooth size in females.Conclusion: Moyer’s and Tanaka and Jhonston method of mesio-distal size prediction are inaccurate when applied in Nepalese population. A new regression equation to predict the size of tooth has been presented.

Introduction. A proportional relationship between the maxillary and mandibular teeth size is required for achieving good finish with proper overjet and overbite postorthodontic treatment. The aims and objectives of this study were to determine the anterior and overall Bolton’s ratio in Nepalese population, to compare Bolton’s ratio between subjects with normal occlusion, Class I malocclusion, and Class II malocclusion, to compare these results with Bolton’s norm, and to determine the frequency of clinically significant (beyond 2 SD) tooth size discrepancy compared to Bolton’s norm. Materials and Methods. The study models of the subjects with normal occlusion and Angle’s Class I malocclusion and Class II malocclusion and fulfilling the inclusion criteria were retrieved from department archives. An electronic digital caliper was used to measure mesiodistal tooth size of the maxillary and mandibular teeth anterior to the second molars. The study sample of 120 study models consisted of the normal occlusion group (n = 31), Class I malocclusion group (n = 47), and Class II malocclusion group (n = 42). These measurements were then used to obtain Bolton’s ratio in three groups of subjects. Bolton’s ratio of study groups was compared with each other and with Bolton’s original ratio. Results. The differences in tooth size ratio of the study groups were not significant statistically, when the groups were compared on the basis of malocclusion or gender. Statistically significant differences were exclusively observed between the study groups and Bolton’s original sample for the anterior ratio. The frequency of the clinically significant tooth size ratio discrepancy was lower for the overall ratio (9.1%) compared to the anterior ratio (22.5%). Conclusions. Bolton’s analysis on the Nepalese population sample shows that there was no significant difference observed on the anterior and overall tooth size ratios when these were compared based on Angle’s malocclusion classes or gender. The clinically significant anterior tooth size discrepancy was more prevalent than that of the overall ratio.

The burning of massive amount of fire crackers on the evening(s) of a nation-wide celebrated festival called ‘Diwali’ in India, gives rise to a remarkably high concentration of criteria air pollutants and it is of utmost importance to investigate the impact of such high loads originated during a relatively shorter time span in a mega-city like Delhi where the situation of ambient air quality has already been alarming almost through-out the year. In view of the same, the present study analyzes available concentration data during this festival’s night for five criteria pollutants namely PM10, PM2.5, SO2, NO2, and CO (Particulate Matter, Sulfur Dioxide, Nitrogen Dioxide and Carbon Monoxide respectively) along with NH3 at six key locations of Delhi. Following the analysis, PM10 concentration in Anand Vihar during nighttime of Diwali was reported to be ~8 times higher than the 24 hours values prescribed by National Ambient Air Quality Standards (NAAQS). On the other hand, the same at IGI airport was recorded lowest even though about 3.5 times that of the guiding standard. PM2.5 concentrations were reported as highest and lowest at RK Puram and Civil lines respectively, in both the cases quite exceeding the comparable standard values. Interestingly, remaining criteria pollutants, namely, SO2, NO2 and CO along with NH3 measured in 2015 showed no values in excess of corresponding 24-hrs guidelines, thereby reporting a better scenario compared to previous years. Further, the extensive use of firecrackers during Diwali festival leads to substantial increase in air pollutants necessitating special measures to control.

This paper reports a preliminary study of the evaluation and forecast of transport-related air pollution dispersion in urban areas with the help of Geographic Information System (GIS) platform and a simulative system with graphical interface. The urban population growth, economic development, energy consumption, growing transportation demand and living standards play major role in pollution exposure in atmosphere. A lot of research has already been done to investigate the functional relationship between air quality and air pollution from transport. This study is an effort to develop a more flexible framework of model to find the exposure of the air pollution in the atmosphere. This review article describes the development of framework of different GIS inputs that help to find the exposure of vehicular pollution in megacity.

The air quality of our indoor environments majorly affects our health. Children are the most exposed to indoor air pollutants as they spend most of their time at home and indoors, the quality of air becomes a major concern in their course of development. While in rural areas the major indoor pollutants are the emissions from combustion sources, in urban areas the particulates and polycyclic aromatic hydrocarbons (PAHs) have chronic and long-term effects. The aim of this study is to review the available literature dealing with various effects of child development. The study showed the relationship between prenatal exposure to airborne PAHs and Child IQ. Children were monitored from in utero to 5 years of age, with determination of prenatal PAH exposure through personal air monitoring for the mothers during pregnancy. It was found that high PAHs level were inversely associated with IQ. The other study comprehended lung development with exposure to nitrogen dioxide, acid aerosols, particulate matter and elemental carbon. Lung function tests were performed annually for 8 years among the children and a decrease in Forced Expiratory Volume (FEV) was observed. The results of the study indicated that current ambient levels of air pollution have chronic and adverse effects on lung development in children leading to significant deficits in FEV as these children reach adulthood. In rural India, the risks associated with indoor air pollution are found to be extremely high. The study revealed that most of the rural households were exposed to acute upper and lower infections, the reason being the use of traditional fuels and poorly ventilated cooking areas. The study focuses on creating awareness towards the adverse effects of indoor air pollution specifically on children health, with reference to the existing studies.