Canine retraction and anchorage loss using self-ligating and conventional brackets with sliding mechanics: A split-mouth clinical study.

OBJECTIVE: Appliance biocompatibility, orthodontic treatment efficiency and patient convenience are the major issues confronting contemporary orthodontic practice. Very few studies have been published till date regarding the efficiency of self-ligating brackets as against conventional brackets. Hence, the present study was planned to compare the rate of canine retraction between self-ligating and conventional brackets and to determine the amount of anchorage loss during canine retraction. METHODS: The present clinical study was designed as a prospective, observational study comprising of 25 patients requiring first premolar extraction as a part of orthodontic treatment. Self-ligating and conventional brackets were bonded using a split-mouth study design randomly. Retraction of canines was done with 150 grams of force using Dontrix gauge with E-chains. The study was conducted in relation to upper arch only, while the rate of retraction was evaluated every 4 weeks for 3 months. Average rates of retraction in 3 months were calculated. For anchorage loss, an acrylic guide plug was used in mid-treatment cast (T0) and after 3 months of retraction (T3). The statistical analysis was done using Statistical Package for Social Sciences (SPSS) version 17.0 (SPSS Inc., Chicago, IL, USA). Independent t-test was used to compare the means of the two variables studied, while Pearson's correlation coefficient was used to evaluate the correlation between the variables studied in the groups included. P < .05 was considered statistically significant. RESULTS: The correlation coefficient between the average rate of canine retraction with self-ligating brackets vs. conventional brackets over a period of 3 months came out to be 0.6434, while on comparing the data in terms of anchorage loss over a period of 3 months, the respective correlation coefficient value was found to be 0.6659 with the results being statistically highly significant in either case (P < .001). CONCLUSIONS: Self-ligating brackets showed double the amount of displacement compared to conventional brackets in some of the cases. Also, chair side time was significantly reduced with self-ligating brackets as against conventional brackets.

Linear Cephalometric Analysis of Pharynx at the Level of Epiglottis among Snorers and Nonsnorers: A Cross-Sectional Study.

Aim Snoring, which falls within the spectrum of sleep-related breathing disorders, is considered to be one of the common symptoms of airway obstruction. Lateral cephalometric analysis is an effective way of diagnosing airway obstruction by evaluating skeletal and soft tissue abnormalities in patients with sleep-disordered breathing (SDB). The present study was planned to analyze the pharyngeal space among snorers and nonsnorers in the retroglossal region and in the region of hypopharynx at the level of epiglottis. Materials and Methods The present cross-sectional study included a total of 60 individuals who were grouped into snorers and nonsnorers based on their answers for the study questionnaire related to snoring. Digital lateral cephalograms were taken for all maintaining the exposure parameters while Digora software was used for measurements related to the soft tissue parameters. The two significant soft tissue parameters analyzed were the distance of epiglottis from the tip of the soft palate, the retroglossal length, and the distance of posterior pharynx from the tip of the epiglottis, the pharyngeal space. Statistical Analysis The statistical analysis was done using Statistical Package for Social Sciences (SPSS) version 17.0 (SPSS Inc., Chicago, Illinois, United States) while paired t -test was used for intergroup analysis. A p -value of < 0.05 was considered statistically significant. Results The mean retroglossal length was found to be 25.52 mm among the snorers and 23.70 mm among the nonsnorers. In case of pharyngeal space, a mean of 8.54 mm was recorded among the snorers whereas among the nonsnorers, the respective mean value of 10.16 mm was observed. Conclusion In the present study, pharyngeal space was found to be less at the level of the tip of epiglottis among the snorers compared with nonsnorers which can be attributed to be one of the significant reasons behind snoring and obstructive sleep apnea syndrome.

Evaluation of Horizontal Distance between WALA-FA Point in Angle's Class I, Class II, and Class III Malocclusion.

INTRODUCTION: The objective of the study was to measure the horizontal distance between the FA-WALA (Facial Axis Point-William Andrews and Larry Andrews) of posterior teeth in Angle's Class I, Class II, and Class III malocclusions and to assess the depth of the Curve of Spee, to find the correlation between intercanine FA and intercanine WALA and its significance. MATERIAL AND METHODS: Sixty pretreatment mandibular casts of patients with an age range of 18-35 years were included. A sample size of 20 was evaluated in Angle's Class I, Class II, and Class III, respectively. The WALA ridge and FA points were marked in the model and calibrated using the digital Vernier caliper. RESULTS: There was an incremental increase in the horizontal distance from the FA-WALA in the posterior teeth. The mandibular intercanine FA-FA and intercanine WALA-WALA distance were greater in Angle's Class III group when compared to Angle's Class II. The Curve of Spee measurement was increased in Angle's Class II group, while Angle's Class III had a flat curve. CONCLUSION: The horizontal distance between FA-WALA increased incrementally in the posterior teeth in Angle's Class I, Class II, and Class III malocclusions. In Angle's Class II malocclusion, the Curve of Spee measurement was increased and had a narrower mandibular arch.

Frictional Forces Produced by Three Different Ligation Methods in Two Different Types of Brackets in 0.016 Nickel-Titanium Wire: An in vitro Study.

INTRODUCTION: The aim of this in vitro study was to compare the frictional forces produced by three types of ligatures (conventional elastic ligatures, unconventional elastic ligatures, and tooth-colored ligature wire) on ceramic bracket and stainless steel brackets with 0.016 nickeltitanium (NiTi) archwire in the dry state. MATERIALS AND METHODS: Twenty each stainless steel brackets and ceramic brackets (0.022 slot central incisor brackets) were mounted on the acrylic block. This assembly was mounted on the Instron machine with the crossheads moving upward at a speed of 10 mm/min in the upper jaw of the Instron machine, one acrylic block with hook and a straight length of 0.016 NiTi wire was attached to it. This wire was ligated to brackets with three different ligation methods. In each test, the brackets were moved a distance of 4 mm, 8 mm, and 12 mm across the central space, and the load cell readings were recorded on the digital display. The difference between the readings is noted. RESULTS: Stainless steel brackets with 0.016 NiTi archwire ligated with conventional, unconventional, and tooth-colored ligation with the movement of 4 mm, 8 mm, and 12 mm shows that the tooth-colored ligation indicating least frictional force decay. Comparison of frictional forces (in newtons) between ceramic brackets and stainless steel brackets using 0.016 NiTi wire for a movement of 12 mm shows that stainless steel bracket with tooth-colored ligation produced least frictional force compared with ceramic bracket. CONCLUSION: Based on this study results, we can conclude that stainless steel brackets produce less frictional force compared to ceramic brackets. Similarly, tooth-colored ligatures can be preferred to reduce friction during leveling stage.

Linear Cephalometric Analysis of Pharynx at the Level of Epiglottis among Snorers and Nonsnorers: A Cross-Sectional Study.

BACKGROUND AND AIM: Snoring, which falls within the spectrum of sleep-related breathing disorders, is considered to be one of the common symptoms of airway obstruction. Lateral cephalometric analysis is an effective way of diagnosing airway obstruction by evaluating skeletal and soft-tissue abnormalities in patients with sleep-disordered breathing. The present study was planned to analyze the pharyngeal space among snorers and nonsnorers in retroglossal region and in the region of the hypopharynx at the level of epiglottis. MATERIALS AND METHODS: The present cross-sectional study included a total of 60 individuals who were grouped into snorers and nonsnorers based on their answers for the study questionnaire related to snoring. Digital lateral cephalograms were taken for all maintaining the exposure parameters, whereas Digora software was used for measurements related to the soft-tissue parameters. The two significant soft-tissue parameters analyzed were the distance of epiglottis from the tip of the soft palate, the retroglossal length and the distance of posterior pharynx from the tip of the epiglottis, the pharyngeal space. STATISTICAL ANALYSIS USED: The statistical analysis was done using the Statistical Package for the Social Sciences (SPSS) version 17.0 (SPSS Inc., Chicago, IL, USA), whereas paired t-test was used for inter-group analysis. P <0.05 was considered statistically significant. RESULTS: The mean retroglossal length was found to be 25.52 mm among the snorers and 23.70 mm among the nonsnorers. In the case of pharyngeal space, a mean of 8.54 mm was recorded among the snorers, whereas among the nonsnorers, the respective mean value of 10.16 mm was observed. CONCLUSION: In the present study, pharyngeal space was found to be less at the level of the tip of epiglottis among the snorers compared to nonsnorers which can be attributed to be one of the significant reasons behind snoring and obstructive sleep apnea syndrome.