Shiva Shanker

Root resorption associated with orthodontic tooth movement: a systematic review.

INTRODUCTION This systematic review evaluated root resorption as an outcome for patients who had orthodontic tooth movement. The results could provide the best available evidence for clinical decisions to minimize the risks and severity of root resorption. METHODS Electronic databases were searched, nonelectronic journals were hand searched, and experts in the field were consulted with no language restrictions. Study selection criteria included randomized clinical trials involving human subjects for orthodontic tooth movement, with fixed appliances, and root resorption recorded during or after treatment. Two authors independently reviewed and extracted data from the selected studies on a standardized form. RESULTS The searches retrieved 921 unique citations. Titles and abstracts identified 144 full articles from which 13 remained after the inclusion criteria were applied. Differences in the methodologic approaches and reporting results made quantitative statistical comparisons impossible. Evidence suggests that comprehensive orthodontic treatment causes increased incidence and severity of root resorption, and heavy forces might be particularly harmful. Orthodontically induced inflammatory root resorption is unaffected by archwire sequencing, bracket prescription, and self-ligation. Previous trauma and tooth morphology are unlikely causative factors. There is some evidence that a 2 to 3 month pause in treatment decreases total root resorption. CONCLUSIONS The results were inconclusive in the clinical management of root resorption, but there is evidence to support the use of light forces, especially with incisor intrusion.

Cephalometric A point changes during and after maxillary protraction and expansion

The purpose of this study was to analyze the treatment and posttreatment maxillary changes achieved with maxillary protraction therapy. The cephalometric records of 25 consecutively treated Chinese children with Class III malocclusions (mean age 8.4 years) were analyzed for cephalometric A point changes, which were then compared with an untreated, age and sex matched Class III control sample. A cephalometric maxillary superimposition technique was used to differentiate between the skeletal and the local contributions to the total A point change. Results showed that 6 months of maxillary protraction therapy produced a mean A point advancement of 2.4 mm compared with 0.2 mm in the control group. Of this advancement, 75% was found to be due to skeletal maxillary advancement and 25% was attributed to local remodeling. Significantly less downward movement of A point was found with treatment compared with the controls, which could be related to the direction of force application. No significant differences were found in the horizontal and the vertical movements of A point between the treatment and the control groups during the 12-month posttreatment period, indicating stability of early maxillary protraction in patients with Class III malocclusions.

Comparison of incisor inclination in patients with Class III malocclusion treated with orthognathic surgery or orthodontic camouflage.

INTRODUCTION Reports comparing Class III patients treated by camouflage and those treated by orthognathic surgery are not numerous. The purpose of this study was to compare the dental and skeletal values of Class III patients treated with these methods against normative data and over the course of treatment. METHODS Thirty-three surgical and 39 camouflage Class III patients were selected from a graduate orthodontic clinic and regional private practices, and lateral cephalograms were digitized. Skeletal and dental values were obtained, and mean and efficacy evaluations referenced to ethnic norms were calculated. RESULTS At pretreatment, the surgery patients had more severe skeletal discrepancies and more compensated incisors. During presurgical orthodontic treatment, most of the surgery groups mandibular incisors were significantly decompensated, although half of the maxillary incisors remained compensated. The surgical move improved 90% of these patients but to only 60% to 65% of the norm. The camouflage group was compensated at pretreatment, and they became more compensated in the end. After treatment, there were no differences between the incisor positions of the 2 groups. CONCLUSIONS There was no statistical difference in incisor inclination and position between the Class III surgical and camouflage groups after treatment; there was a significant difference in the pretreatment and posttreatment incisor inclination and position compared with normative values for both the surgical and the camouflage groups; the maxillary and mandibular incisors were not adequately decompensated in the surgical group, but significant improvement in mandibular incisor position and axial inclination was achieved presurgically. The outcome of the surgical correction was limited by the inadequate presurgical orthodontic incisor decompensation, and orthodontic compensation of incisors occurred postsurgically to achieve an optimal occlusal result.

Dental and skeletal changes associated with Class II surgical-orthodontic treatment

INTRODUCTION Few published reports detail the dental changes produced by orthodontic treatment in conjunction with orthognathic surgery. METHODS Thirty-four Class II subjects who underwent surgical-orthodontic treatment with mandibular advancement and rigid fixation were selected, and their lateral cephalograms were digitized. Mean skeletal and dental values were calculated for pretreatment, presurgical, and final treatment times. Treatment efficacy as a percentage of an ideal goal achieved also was calculated. RESULTS All data showed significant positive changes in the position of the mandible. The mean changes showed that the maxillary incisors were overretracted presurgically and then returned to a normal position postsurgically, whereas the mandibular incisors were proclined and protruded presurgically and remained so at posttreatment. The efficacy data showed that the incisors were not ideally decompensated in many patients. CONCLUSIONS The efficacy data show that presurgical orthodontic treatment often does not fully decompensate the incisors; this then limits the surgical outcome.

Evaluation of objective structured clinical examination for advanced orthodontic education 12 years after introduction

Introduction: Advanced education programs in orthodontics must ensure student competency in clinical skills. An objective structure clinical examination has been used in 1 program for over a decade. The results were analyzed cross‐sectionally and longitudinally to provide insights regarding the achievement of competency, student growth, question difficulty, question discrimination, and question predictive ability. Methods: In this study, we analyzed 218 (82 first‐year, 68 second‐year, and 68 third‐year classes) scores of each station from 85 orthodontic students. The grades originated from 13 stations and were collected anonymously for 12 consecutive years during the first 2 decades of the 2000s. The stations tested knowledge and skills regarding dental relationships, analyzing a cephalometric tracing, performing a diagnostic skill, identifying cephalometric points, bracket placement, placing first‐order and second‐order bends, forming a loop, placing accentuated third‐order bends, identifying problems and planning mixed dentition treatment, identifying problems and planning adolescent dentition treatment, identifying problems and planning nongrowing skeletal treatment, superimposing cephalometric tracings, and interpreting cephalometric superimpositions. Results were evaluated using multivariate analysis of variance, chi‐square tests, and latent growth analysis. Results: The multivariate analysis of variance showed that all stations except 3 (analyzing a cephalometric tracing, forming a loop, and identifying cephalometric points) had significantly lower mean scores for the first‐year student class than the second‐ and third‐year classes (P <0.028); scores between the second‐ and third‐year student classes were not significantly different (P >0.108). The chi‐square analysis of the distribution of the number of noncompetent item responses decreased from the first to the second years (P <0.0003), from the second to the third years (P <0.0042), and from the first to the third years (P <0.00003). The latent growth analysis showed a wide range of difficulty and discrimination between questions. It also showed continuous growth for some areas and the ability of 6 questions to predict competency at greater than the 80% level. Conclusions: Objective structure clinical examinations can provide a method of evaluating student performance and curriculum impact over time, but cross‐sectional and longitudinal analyses of the results may not be complementary. Significant learning appears to occur during all years of a 3‐year program. Valuable questions were both easy and difficult, discriminating and not discriminating, and came from all domains: diagnostic, technical, and evaluation/synthesis. HighlightsThe OSCE can help examine student learning and curriculum changes.Significant learning appears to occur during all years of a 3‐year program.Cross‐sectional and longitudinal analyses may not be complementary.Discriminating and predictive questions can be from different domains of skills.Both difficult and easy questions can be discriminating and predictive.