World Journal of Orthodontics

AIM: Rapid palatal expansion (RPE) is used for treatment of skeletal crossbites. It may be combined with a face mask if the maxilla is to be protracted. Conventional tooth-borne appliances rely on an almost complete dentition to transmit the relatively high forces to the bony structures of the maxilla and midface. In most situations, tooth-borne appliances produce adverse effects such as buccal tipping of the lateral teeth, imposing the risk of recessions and vestibular bone fenestrations...

A 20-year-old woman presented with a labially displaced mandibular right central incisor with severe attrition. Her maxillary dentition was well-aligned, and she had a straight profile. The respective central incisor was extracted. Subsequently, all teeth were aligned and the extraction space was closed with 2D lingual brackets. The result was esthetically pleasing.

This report presents a case of a patient who developed a supernumerary mandibular premolar during the course of orthodontic treatment. Evidence of this tooth comes from consecutive panoramic radiographs. It is not routine practice to screen for developing supernumerary teeth during orthodontic treatment. Therefore, the possibility of supernumerary tooth interference with occlusal development or orthodontic treatment should always be kept in mind. A brief review of literature concerning the late formation of supernumerary teeth is included...

AIM: To examine the muscular response of masseter and anterior temporal muscles to functional orthodontic treatment in skeletal open-bite and deep-bite subjects using electromyography (EMG). METHODS: The study sample consisted of 31 subjects (18 males, 13 females) grouped into skeletal open-bite (mean age 12.6 ± 2.5 years) and deep-bite (mean age 11.6 ± 2.1 years) groups and into prepubertal and pubertal growth stages. All subjects received functional orthognathic treatment...

AIM: To determine the correlation among chronologic age, skeletal maturity, and dental age in reference to both sexes. METHODS: In 380 subjects (147 males and 233 females) between 7 and 17 years of age, skeletal maturity was assessed using the cervical vertebral maturation stages described by Baccetti et al. Dental age was determined using the Demirjian method. The correlation between skeletal maturity and chronologic age on one side and between skeletal maturity and dental age on the other was assessed with Spearman rank correlation coefficients...

AIM: To assess whether the forces created by the magnetic resonance imaging (MRI) field cause a deflection of orthodontic stainless steel archwires or a change of their mechanical properties. METHODS: Sixty stainless steel 0.016-inch archwires were divided into three groups of 20 wires each. The control group was as received from the manufacturer, the MRI 1 group had wires attached to brackets on artificial teeth subjected to MRI (1.5 Tesla), and the MRI 2 group had activated T-loops subjected to MRI (1...

AIM: To compare the initial cephalometric characteristics of complete Class II malocclusions treated with nonextraction or with two maxillary premolar extractions and to verify their degree of influence on the occlusal success rate. METHODS: A sample of 84 records from patients with complete Class II malocclusions was divided into two groups. Group 1 consisted of 31 patients treated with nonextraction at an initial mean age of 12.95 years, while group 2 included 53 patients treated with two maxillary premolar extractions at an initial mean age of 13...

AIM: To determine whether there is sexual dimorphism regarding Bolton ratios within four ethnic groups and to compare them against Bolton standards. METHODS: The sample consisted of 140 dental study casts of untreated normal occlusion subjects, derived from four racial groups: black, white, Afro-Mediterranean, and Japanese. Anterior and overall Bolton ratios were calculated for each cast. The Kolmogorov-Smirnov test, t test, and one-way ANOVA were used. RESULTS: No statistically significant sexual dimorphism in anterior or total tooth-size ratios were found within any group...

AIM: Accelerating the speed of orthodontic tooth movement should contribute to the shortening of the treatment period. This study was designed to determine whether a pulsed electromagnetic field (PEMF) affects orthodontic tooth movement. METHODS: The canines of one side of 10 patients (mean age 23.0 ± 3.3 years) who needed canine retraction were exposed to a PEMF; the canines on the contralateral sides of the same patients were not similarly exposed. After extraction of the maxillary first premolars, both canines were retracted with coil springs...

AIM: To find the cephalometric norms for Palestinian population according to Steiner cephalometric analysis. METHODS: Lateral cephalograms of 76 dental students (51 females and 25 males, mean age 20.4 ± 2.1 years) were collected from their files at the American University in Jenin, Palestine. They were scanned and analyzed following Steiner measurements. Means and standard deviations for all variables were calculated. Differences between the mean of the variables for both sexes were calculated using the independent t test...

AIM: To evaluate the amount of initial force and to compare the amount of force decay between the elastomeric chain and tie-back method over a period of time. METHODS: Twenty five-unit elastomeric chains (15 mm) stretched 100%, and twenty elastic modules in tie-back method stretched twice their original diameter were held in place by a series of pins 30-mm apart in acrylic blocks. The blocks were stored in 37 °C distilled water. The force of all samples was measured at baseline, 24 and 48 hours, and once a week thereafter for 4 weeks with a force gauge...

In general, the success of Class II treatment depends as much on the skill of the orthodontist as it does on a favorable facial-growth pattern. Lack of sufficient favorable growth during treatment will make it difficult to correct the skeletal malrelationship or significantly improve the facial profile. The case report presents the treatment of a patient with a Class II, Division 1 malocclusion with severe overjet and a hyperdivergent growth pattern.

AIM: To examine the level of discomfort and pain reported by patients during debonding of orthodontic metallic brackets by comparing two of the most popular methods, since discomfort can negatively influence patients' motivation to undergo orthodontic treatment. METHODS: This split-mouth designed study involved 37 patients. Two methods were used for bracket removal: a lift-off debonding instrument and a ligature-cutting plier. The level of discomfort during debonding was evaluated on a scale of 0 to 4; The Adhesive Remnant Index (ARI) was taken into consideration, as well...

AIM: To measure the arch length of sides containing palatally displaced canines and to compare them with those of contralateral sides with normally positioned canines. METHODS: The study sample consisted of 36 children 10 to 12 years of age with unerupted permanent maxillary canines who presented with palatally displaced canines, unilaterally, with respect to the maxillary lateral incisors. The palatal displacement was evaluated using the horizontal tube shift method with periapical radiographs, after the canine cusp tips were found to overlap their adjacent lateral incisors on panoramic radiographs...

AIM: Orthodontic need assessment is instrumental for dental treatment planning. The objective of this examination was to evaluate the orthodontic treatment need of students in Shiraz, Iran, using the Dental Aesthetic Index (DAI) and to assess the relationship between DAI and sociodemographic variables. METHODS: Using random cluster sampling, 1,818 pupils (965 male and 853 female) 14 to 18 years of age without any history of orthodontic treatment were selected. Information was gathered using a questionnaire, including demographics such as sex, family size, and parents' education...

AIM: To compare friction (F) of conventional and ceramic brackets (0.022-inch slot) using a model that tests the sliding of the archwire through 10 aligned brackets. METHODS: Polycrystalline alumina brackets (PCAs), PCA brackets with a stainless steel slot (PCA-M), and monocrystalline sapphire brackets (MCS) were tested under elastic ligatures using various archwires in dry and wet (saliva) states. Conventional stainless steel brackets were used as controls. RESULTS: In both dry and wet states, PCA and MCS brackets expressed a statistically significant higher F value with respect to stainless steel and PCA-M brackets when combined with the rectangular archwires (P<...

AIM: To determine with a cross-sectional study the prevalence of orthodontic treatment need using the Dental Aesthetic Index (DAI). SUBJECTS AND METHODS: Using a stratified sampling method in private and public schools in Isfahan, Iran, 748 subjects were examined and divided into three age groups: 11 to 14, 14 to 17, and 17 to 20 years (355 females and 393 males, 15.11 ± 2.23 years), including 20 subjects with history of orthodontic treatment. DAI scores were recorded in those without history of orthodontic treatment (n=728, 340 females and 388 males)...

The present article illustrates a treatment option for managing the skeletal Class II malocclusion complicated by a deep bite and short face in an adult and emphasizes the limitations of such an approach and its potential complications. The patient had an inadequate tooth display upon smiling and a deep lower curve of Spee. Treatment consisted of a double jaw surgery with a maxillary three-piece LeFort to expand, downgraft, and advance the maxilla and a bilateral sagittal split osteotomy to advance the mandible...

AIM: To establish soft tissue norms using profile angles and esthetic analysis in the South Indian population. METHODS: A clinically effective method is used for accurately placing the esthetic horizontal line on cephalometric radiograph. A series of two vertical lines provides the determinants for the horizontal positions of the soft tissue chin, soft tissue chin thickness, upper lip position and thickness, lower lip, maxillary incisors, and mandibular incisors in relation to the profile...

AIM: To evaluate the effects of rapid maxillary expansion (RME) and face mask combination therapy on the soft and hard tissue profile and to determine the possible correlations between hard and soft tissue changes. METHODS: Soft and hard tissue parameters were measured in cephalometric radiographs of 33 subjects. The treatment group consisted of 18 Class III patients (11 males and 7 females, mean age 11.7 ± 1.9 years), and the control group contained 15 untreated Class III subjects (10 males and 5 females, mean age 9...