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1.
Cureus ; 16(6): e62121, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38993465

ABSTRACT

Introduction Orthodontic mechanics involves transferring some of the applied force to the tooth's supporting components via friction, which in turn allows the tooth to move more easily. Aim The purpose of this in vitro experiment was to examine the frictional resistance (FR) of different lingual brackets utilizing Instron universal testing machines and nitinol (NiTi) archwires of varying sizes. Materials and methods Twenty-four sectional anterior die stones were replicated from a study model. They were categorized into eight categories, with the Libral lingual bracket and the JJ lingual bracket having 0.012" and 0.014" inch NiTi archwire, which were further subdivided into six subgroups. Three brackets were bonded to the anterior teeth of the upper and lower segments and replicated on other models with the help of silicon putty. Elastomeric modules were ligated to two diameters of NiTi wire (0.012" and 0.014") in each model. An Instron universal testing machine was used to measure the frictional force. Numerical data and descriptive statistics such as mean and standard deviation have been shown. Results In the overall analysis, it was observed that among JJ Orthodontics samples using 0.012" NiTi archwires, the maxilla exhibited a higher FR (4.205N) compared to the mandible (4.092N). Similarly, in the case of Libral Orthodontics samples with 0.012" NiTi archwires, the maxilla also demonstrated a higher FR (5.10N) than the mandible (4.97N). However, this trend did not hold for samples using 0.014" NiTi archwires. There was a statistically nonsignificant difference (p > 0.05) in the values between all the pairs of groups. Conclusion The present study concludes that Libral lingual brackets produced overall more FR than JJ lingual brackets.

2.
J Pharm Bioallied Sci ; 16(Suppl 1): S835-S837, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38595370

ABSTRACT

Background: This study examines the surface changes of stainless steel miniplates and screws after their retrieval from patients who underwent maxillofacial trauma and orthognathic surgery. The assessment focuses on comparing the alterations in these materials, aiming to contribute to our understanding of their durability and performance in clinical settings. Materials and Methods: A total of 60 stainless steel miniplates and screws were collected from 30 patients who had previously undergone either maxillofacial trauma or orthognathic surgery. The retrieved miniplates and screws were carefully removed from the patients and cleaned to remove any organic debris. Each specimen was then examined for surface changes. Surface changes were evaluated using visual inspection, scanning electron microscopy (SEM), and roughness measurements. Visual inspection provided a qualitative assessment, while SEM allowed for a more detailed examination of the surfaces. Roughness measurements were conducted using a profilometer. Results: Visual inspection revealed varying degrees of surface changes in the retrieved miniplates and screws. These changes included scratches, corrosion, and discoloration. SEM analysis confirmed the presence of surface alterations, with some specimens showing more significant damage, such as pitting and cracks. Roughness measurements indicated an increase in surface roughness for both miniplates and screws, suggesting that the surfaces had become less smooth. Conclusion: This comparative study of stainless steel miniplates and screws retrieved from maxillofacial trauma and orthognathic surgery patients demonstrated that these materials undergo surface changes over time.

3.
Cureus ; 16(3): e55898, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38595882

ABSTRACT

BACKGROUND: Orthodontic treatment is a widely embraced intervention aimed at enhancing dental aesthetics and correcting malocclusions among adolescents. However, concerns persist regarding its potential impact on oral health, particularly on the development of dental caries. This study aimed to systematically investigate the relationship between orthodontic treatment and the incidence of new carious lesions among adolescents. METHODS: A prospective cohort design involving adolescents aged 12-18 years was employed. A total of 82 patients met the inclusion criteria. In addition, an age-matched control group of 82 participants who did not undergo orthodontic treatment was included. The study included both a treatment group undergoing orthodontic treatment (braces or aligners) and an age-matched control group that did not undergo any orthodontic intervention. Demographic characteristics, orthodontic treatment details, and oral hygiene practices were documented at baseline and throughout the study period. Dental examinations at six-month intervals post-treatment were conducted to track the incidence and progression of carious lesions. RESULTS: The demographic characteristics, baseline oral health status, orthodontic treatment details, and oral hygiene practices were comparable between the treatment and control groups. Post-orthodontic treatment assessment revealed a slightly higher incidence of new carious lesions in the treatment group (14.6%) than in the control group (9.8%), although this difference was not statistically significant (p = 0.15). Dental examinations at six-month intervals demonstrated a gradual increase in caries incidence over time in both groups, with no substantial disparities observed. CONCLUSIONS: This study provides a comprehensive examination of the relationship between orthodontic treatment and the incidence of new carious lesions among adolescents. While a trend towards higher caries incidence in the treatment group was observed, the difference was not statistically significant. These findings contribute to the existing body of knowledge and emphasize the need for ongoing research to guide clinical practice.

4.
Cureus ; 15(3): e36032, 2023 Mar.
Article in English | MEDLINE | ID: mdl-37056541

ABSTRACT

INTRODUCTION: Filler size affects how the material is coated and finished, while filler stacking affects how strong the material is, how flexible it is, how resistant it is to wear, and how much it shrinks when it polymerizes. The purpose of this research was to compare micro-hybrid, nano-composite, and bulk-fill composites with respect to their compressive strength, diametric tensile strength, and flexural strength. MATERIALS AND METHODS: To organize the samples according to International Organization for Standardization (ISO) 4049 and American Dental Association (ADA) detail number 27, we used a custom-made Teflon mold. A total of 45 samples were used, with 15 samples in each group. The sample was mounted on a state-of-the-art general testing machine to determine its compressive strength and polar rigidity. The 3-point bowing test was used to determine flexural strength. A one-way analysis of variance (ANOVA) was used for quantitative analysis, followed by a post hoc test with a significance level of P < 0.05. RESULTS: The Tetric N Ceram Bulk Fill, the Filtek Z350 XT nanocomposite, and the T-Econom micro-hybrid composite all had different levels of flexural and compressive strength. This difference was statistically significant. Nanocomposites have superior compressive and flexural strengths to their counterparts analyzed in the present study. CONCLUSION: Nano-composite combines the properties of being strong and looking good. It can be used in both front and back restorations that need to be strong enough to withstand the forces of chewing.

5.
Appl Biochem Biotechnol ; 183(3): 1008-1025, 2017 Nov.
Article in English | MEDLINE | ID: mdl-28474218

ABSTRACT

In the present study, press mud, a sugar industry waste, was explored for biobutanol production to strengthen agricultural economy. The fermentative production of biobutanol was investigated via series of steps, viz. characterization, drying, acid hydrolysis, detoxification, and fermentation. Press mud contains an adequate amount of cellulose (22.3%) and hemicellulose (21.67%) on dry basis, and hence, it can be utilized for further acetone-butanol-ethanol (ABE) production. Drying experiments were conducted in the temperature range of 60-120 °C to circumvent microbial spoilage and enhance storability of press mud. Furthermore, acidic pretreatment variables, viz. sulfuric acid concentration, solid to liquid ratio, and time, were optimized using response surface methodology. The corresponding values were found to be 1.5% (v/v), 1:5 g/mL, and 15 min, respectively. In addition, detoxification studies were also conducted using activated charcoal, which removed almost 93-97% phenolics and around 98% furans, which are toxic to microorganisms during fermentation. Finally, the batch fermentation of detoxified press mud slurry (the sample dried at 100 °C and pretreated) using Clostridium acetobutylicum NRRL B-527 resulted in a higher butanol production of 4.43 g/L with a total ABE of 6.69 g/L.


Subject(s)
Biotechnology/methods , Butanols/metabolism , Clostridium acetobutylicum/metabolism , Industrial Waste , Saccharum/chemistry , Fermentation , Green Chemistry Technology , Hydrolysis
6.
Bioresour Technol ; 225: 359-366, 2017 Feb.
Article in English | MEDLINE | ID: mdl-27939964

ABSTRACT

Present investigation explores the use of pineapple peel, a food industry waste, for acetone-butanol-ethanol (ABE) production using Clostridium acetobutylicum B 527. Proximate analysis of pineapple peel shows that it contains 35% cellulose, 19% hemicellulose, and 16% lignin on dry basis. Drying experiments on pineapple peel waste were carried out in the temperature range of 60-120°C and experimental drying data was modeled using moisture diffusion control model to study its effect on ABE production. The production of ABE was further accomplished via acid hydrolysis, detoxification, and fermentation process. Maximum total sugar release obtained by using acid hydrolysis was 97g/L with 95-97% and 10-50% removal of phenolics and acetic acid, respectively during detoxification process. The maximum ABE titer obtained was 5.23g/L with 55.6% substrate consumption when samples dried at 120°C were used as a substrate (after detoxification).


Subject(s)
1-Butanol/metabolism , Ananas/chemistry , Biotechnology/methods , Clostridium acetobutylicum/metabolism , Industrial Waste , Acetone/metabolism , Ananas/metabolism , Cellulose/analysis , Cellulose/metabolism , Desiccation , Ethanol/metabolism , Fermentation , Food Industry , Fruit/chemistry , Hydrolysis , Kinetics , Lignin/analysis , Lignin/chemistry , Models, Theoretical , Monosaccharides/metabolism , Polysaccharides/analysis , Polysaccharides/metabolism
7.
J Clin Diagn Res ; 10(9): ZC20-ZC23, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27790573

ABSTRACT

INTRODUCTION: Two aspects of the smile: the Smile Arc (SA) and Buccal Corridors (BC) have been the interest of the orthodontist in recent years. AIM: The present study was undertaken to evaluate the influence of the smile arc and buccal corridors on facial attractiveness as evaluated by orthodontists, general dentists and laymen. MATERIALS AND METHODS: Two subjects (one male & one female) were selected from the regional population fulfilling the criteria of an ideal smile arc and ideal buccal corridors. Frontal smile view photographs of these subjects were taken and modified by using adobe photoshop 7.0 to create combination of three smile arc variance and three buccal corridors variations respectively which were shown to 25 orthodontists, 25 general dentists & 25 laymen, to rate the facial attractiveness of each image on a rating scale. RESULTS: All the three groups (laypersons, dentists and orthodontists) showed significant difference in ratings, indicating that they had different perceptions on the facial attractiveness. CONCLUSION: Orthodontists were more precise in discerning the smile arc and buccal corridors compared to dentists and laypersons.

8.
J Forensic Dent Sci ; 8(3): 139-144, 2016.
Article in English | MEDLINE | ID: mdl-28123267

ABSTRACT

BACKGROUND: The study mentioned was aimed to examine the contribution of the objective measures representing anterior-posterior (AP) and vertical characteristics, dental esthetics, or their combination that are used in daily orthodontic practice in the assessment of the facial esthetics. MATERIALS AND METHODS: A panel of 64 laypersons evaluated the facial esthetics of 32 boys and 32 girls, stratified over four different angle classes, on a visual analog scale. The relationship between the objective parameters and facial esthetics was evaluated by the backward multiple regression analysis. RESULTS: Dental esthetics, expressed by the esthetic component of the index of orthodontic treatment need (AC/IOTN), appeared to be the most vital indicator for facial esthetics. The horizontal sum, a variable for AP characteristics of the patient, could be a better variable when compared with the overjet. CONCLUSION: Addition of this newly defined parameter to the AC/IOTN improved the prognostic value from 25% to 35%.

9.
J Int Oral Health ; 6(5): 27-30, 2014 Sep.
Article in English | MEDLINE | ID: mdl-25395789

ABSTRACT

BACKGROUND: This study aimed to know the prevalence of dental caries among children having malocclusion. MATERIALS AND METHODS: This cross-sectional study included 880 students aged 1215 years, among whom 488 were boys and 392 were girls. A proforma was prepared to record dental caries status and dental esthetic index (DAI) using the WHO Oral Health Assessment Form (1997). Data were analyzed using Student's t-test and ANOVA. The P value of 0.05 or less was considered as statistically significant. RESULTS: It was found that 644 (73.2%) had no abnormality or minor malocclusion, whereas 115 (13.0%), 100 (11.4%) and 21 (2.4%) had definite, severe and very severe or handicapping malocclusion, respectively. Overall mean of decayed teeth (DT) component was found to be 0.95 ± 1.006, missing teeth 0.23 ± 0.670 and filled teeth 0.23 ± 0.559 and decayed, missing, filled tooth (DMFT) was 1.41 ± 1.483. DT and overall DMFT component significantly increased with increasing DAI of malocclusion (P ≤ 0.05). CONCLUSION: The severity of dental caries showed positive relation with DAI and age.

10.
J Clin Diagn Res ; 8(5): ZD30-2, 2014 May.
Article in English | MEDLINE | ID: mdl-24995261

ABSTRACT

Most Class II division 2 malocclusion manifest a severe deep bite, the orthodontic correction of deep overbite can be achieved with several mechanisms one such mechanics is true intrusion of anterior teeth. Deep overbite correction by intrusion of anterior teeth affords a number of advantages which includes simplifying control of the vertical dimension and allowing forward rotation of mandible to aid in Class II correction. It also aid in correction of a high gingival smile line. This case report presents the patient of a 14-year-old boy with Class II division 2 subdivision malocclusion treated with connecticut intrusion arch and also highlights the biomechanical aspect of this appliance. Intrusion of anterior teeth is difficult. An appropriate, effective and clinically manageable biomechanical system is required. The treatment approach shown in this case can treat the deep overbite precisely with incisor intrusion. The article shows the versatility of Connecticut Intrusion Arch and by applying the sound biomechanical principles we can execute the planned mechanics with minimal side effects.

11.
Ultrason Sonochem ; 15(4): 554-563, 2008 Apr.
Article in English | MEDLINE | ID: mdl-17698396

ABSTRACT

Ultrasonic emulsification of oil and water was carried out and the effect of irradiation time, irradiation power and physicochemical properties of oil on the dispersed phase volume and dispersed phase droplet size has been studied. The increase in the irradiation time increases the dispersed phase volume while decreases the dispersed phase droplets size. With an increase in the ultrasonic irradiation power, there is an increase in the fraction of volume of the dispersed phase while the droplet size of the dispersed phase decreases. The fractional volume of the dispersed phase increases for the case of groundnut oil-water system while it is low for paraffin (heavy) oil-water system. The droplet size of soyabean oil dispersed in water is found to be small while that of paraffin (heavy) oil is found to be large. These variations could be explained on the basis of varying physicochemical properties of the system, i.e., viscosity of oil and the interfacial tension. During the ultrasonic emulsification, coalescence phenomenon which is only marginal, has been observed, which can be attributed to the collision of small droplets when the droplet concentration increases beyond a certain number and the acoustic streaming strength increases.


Subject(s)
Emulsions/radiation effects , Ultrasonics , Algorithms , Chemical Phenomena , Chemistry, Physical , Paraffin/chemistry , Paraffin/radiation effects , Particle Size , Peanut Oil , Plant Oils/chemistry , Plant Oils/radiation effects , Soybean Oil/chemistry , Soybean Oil/radiation effects , Surface Tension , Time Factors , Viscosity
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