Clinical photography vs digital video clips for the assessment of smile esthetics

Objective: To test the null hypothesis that there is no clinically significant difference between the post–orthodontic treatment images of smiles of subjects captured by clinical photography and the smiles of the same subjects obtained from digital video clips.Materials and Methods:Clinical photographs and digital video captures were obtained from 48 orthodontically treated patients. An updated version of the Smile Mesh^TM program was used to quantify and compare smile characteristics obtained with the two methods. A paired-samples t-test was performed to test for mean differences in Smile Mesh measurements generated from both smile images. The relationship between the various Smile Mesh measurements obtained from both smile images was examined by way of Pearson product-moment correlation.Results:A significant difference was found between 7 of the 14 mean Smile Mesh measurements. The absolute values of all these differences, however, were smaller than 1 mm and therefore were not clinically significant. With the exception of lower lip to maxillary incisor, all measurements showed a moderate to strong relation with each other (P values ranging from .47 to .82; P < .001).Conclusions:The hypothesis cannot be rejected. A significant positive correlation was noted between Smile Mesh measurements obtained from smiles captured by clinical photography and those captured with digital video clips. This supports the conclusion that a standard digital photograph appears to be a valid tool for analysis of the posttreatment smile.     

Stability of maxillary interincisor diastema closure after extraction orthodontic treatment

ObjectivesTo evaluate the stability of maxillary interincisor diastema closure and the relationship between space relapse and interincisor diastema width, overjet, overbite, angulations between adjacent maxillary anterior teeth and presence of intermaxillary osseous cleft after orthodontic treatment with extractions.Materials and MethodsTwenty-four individuals with a maxillary interincisor diastema pretreatment, treated with maxillary first premolar extractions were evaluated. Dental casts and panoramic radiographs taken at pretreatment (T1), posttreatment (T2), and posttreatment follow-up (T3) were assessed. Periapical radiographs at T1 and T2 were also evaluated. Diastema relapse was assumed when T3-T2 interincisor space change was greater than zero. Diastema relapse was considered clinically significant when it was at least 0.50 mm. Data were analyzed using repeated-measures analysis of variance followed by post hoc Tukey tests or Friedman followed by Wilcoxon tests. T-test or Mann-Whitney U-test, Pearson correlation coefficient, and multiple linear regression analyses were also performed.ResultsNo statistically significant relapse of maxillary interincisor diastemas was found. The percentage of clinically significant relapse of the maxillary interincisor diastemas was 27.78%. Specifically, for the interincisor midline diastema, it was 8.33%.ConclusionsMaxillary interincisor diastema closure showed no statistically significant relapse after orthodontic treatment with premolar extractions. Clinically significant stability for maxillary interincisor diastema closure was 72.22% and, specifically, for interincisor midline diastema closure, it was 91.67%.     

Effectiveness of metronidazole gel and mobile telephone short-message service reminders on gingivitis in orthodontic patients:: A double-blind randomized controlled trial

ObjectivesTo compare the effectiveness of metronidazole gel and mobile telephone short-message service (SMS) reminders on gingivitis in patients undergoing fixed orthodontic treatment.Materials and MethodsThe trial was double blinded (patient and investigator), and only the clinical trial unit pharmacist was unblinded. Data were collected from patients undergoing fixed orthodontic treatment for at least 6 months. A total of 66 patients were randomly assigned to either 0.8% metronidazole gel (n = 22), SMS reminder and placebo gel (n = 22), or placebo (control) group only (n = 22). Gingival index (GI), bleeding index (BI), and orthodontic plaque index (OPI) were evaluated on several teeth at baseline (T₀) and after 4 weeks (T₁). Paired-sample t-tests were used to compare mean differences of indexes at T₀ and T₁ in the groups, and independent-sample t-tests were used to determine the effects of interventions compared with the controls.ResultsData from 64 patients were analyzed; there were 2 dropouts. There were statistically significant (P < .05) reductions in GI, BI, and OPI scores from T₀ to T₁ for each intervention. However, there were no significant differences between each intervention and the control group. There were no adverse effects.ConclusionsThe null hypothesis could not be rejected. There is no difference between interventions (application of 0.8% metronidazole gel and SMS reminder for reinforcing oral hygiene) in reducing gingival inflammation in orthodontic patients.     

Comparison of perception of necessity of orthodontic treatment between orthodontists and dentists at dental check-ups with DAI

PurposeThe aims of this study were to examine the gaps in the perception of the necessity of orthodontic treatment between orthodontists and dentists, and identify the items influencing perception using the Dental Aesthetic Index (DAI).Materials and methodsBoth dentists and orthodontists assessed the necessity of orthodontic treatment in the 693 junior and senior high school students, and orthodontists examined the occlusion of the students with DAI. The data were analyzed with Student's t-test, Bonferroni multiple comparison test and decision analysis.ResultsIn the orthodontist’ perception, clearly significant differences were observed in all DAI items between necessary and unnecessary groups. However, maxillary missing teeth, mandibular missing teeth, spacing and diastema did not show a clear difference in the dentists’ perception. In the comparison of perception between orthodontists and dentists, crowding, largest anterior maxillary irregularity and largest mandibular irregularity showed significant differences. Decision analysis demonstrated that crowding was the most important item for both orthodontists and dentists.ConclusionThere were two types of gaps in the perception of the necessity of orthodontic treatment. The first one is an individual difference among the dentists, which is related to the evaluation of missing teeth and space in the dental arches. The other is recognized as gaps in the perception between orthodontists and dentists, which are related to the amounts of crowding. It is important to realize the difference of perception and improve the mutual understanding to prevent overlooking malocclusion.     

Contribution of cone beam computed tomography to the detection of apical root resorption after orthodontic treatment in root-filled and vital teeth

Objective:To investigate whether root-filled teeth are similar to vital pulp teeth in terms of apical root resorption (ARR) after orthodontic treatment.Materials and Methods:An original sample of cone beam computed tomography (CBCT) images of 1256 roots from 30 orthodontic patients were analyzed. The inclusion criteria demanded root-filled teeth and their contralateral vital teeth, while teeth with history of trauma had to be excluded to comply with exclusion criteria. CBCT images of root-filled teeth were compared before and after orthodontic treatment in a split-mouth design study. Tooth measurements were made with multiplanar reconstruction using axial-guided navigation. The statistical difference between the treatment effects was compared using the paired t-test.Results:Twenty posterior root-filled teeth and their contralaterals with vital pulp were selected before orthodontic treatment from six adolescents (two boys and four girls; mean [SD] age 12.8 [1.8] years). No differences were detected between filled and vital root lengths before treatment (P  =  .4364). The mean differences in root length between preorthodontic and postorthodontic treatment in filled- and vital roots were −0.30 mm and −0.16 mm, respectively, without any statistical difference (P  =  .4197) between them.Conclusion:There appears to be no increase in ARR after orthodontic treatment in root-filled teeth with no earlier ARR.     

Quantification of three-dimensional orthodontic force systems of T-loop archwires

Objective:To demonstrate the three-dimensional (3D) orthodontic force systems of three commercial closing T-loop archwires using a new method and to quantify the force systems of the T-loop archwires.Materials and Methods:An orthodontic force tester (OFT) and a custom-made dentoform were developed to measure force systems. The system simulated the clinical environment for an orthodontic patient requiring space closure, which included measurement of three force components along, and three moment components about, three clinically defined axes on two target teeth. The archwires were attached to the dentoform and were activated following a standard clinical procedure. The resulting force system was measured using the OFT.Results:The force systems of the T-loops on the teeth were 3D. Activation in one direction resulted in force and moment components in other directions (side effects). The six force and moment components as well as the moment-to-force ratios in the clinically defined coordinate system were quantified.Conclusions:The commercial archwires do not provide force systems for pure translation. Quantification of the force system is critical for the selection and design of optimal orthodontic appliances.     

Comparison of Orthodontic Root Resorption of Root-filled and Vital Teeth Using Micro–computed Tomography

ObjectiveTo evaluate the difference in orthodontic root resorption between root-filled and vital teeth.Material and MethodsSixteen individuals who required bilateral premolar tooth extraction due to orthodontic treatment and had a previously root-filled premolar tooth on one side were included in the study. The experimental group consisted of root-filled premolar teeth, and the control group consisted of contralateral vital premolar teeth. A 150-g buccally directed force was applied to these teeth using 0.017 × 0.025-inch TMA cantilever springs. The premolars were extracted 8 weeks after the application of force. Images were obtained using micro–computed tomography. Resorption measurements were obtained using the Image J program.ResultsThe mean values for resorption were 0.08869 mm³ for the root-filled teeth and 0.14077 mm³ for the contralateral teeth, indicating significantly less resorption for the root-filled teeth compared with the contralateral teeth after the application of orthodontic force (P = .003). In both groups, the most resorption was seen on the cervical-buccal and apical-lingual surfaces. The mean resorption value of the cervical region was 0.06305 mm³ in the control group and 0.0291 mm³ in the experimental group, and the difference was statistically significant (P = .002).ConclusionsRoot-filled teeth showed significantly less orthodontic root resorption than vital teeth.     

A novel method for volumetric assessment of tooth wear using three-dimensional reverse-engineering technology: A preliminary report

Objective:To describe a newly developed three-dimensional (3D) digital superimposition method for quantitative evaluation of tooth wear that occurs during orthodontic treatment.Materials and Methods:The sample consisted of dental casts obtained from 56 patients (23 male patients and 33 female patients; mean ± standard deviation age  =  21.8 ± 5.1 years) who received orthodontic treatment with extraction of four premolars. The maxillary and mandibular dental casts taken before (T1) and after (T2) orthodontic treatments were scanned, and 3D images of the canines were constructed. The canines at T1 were superimposed with those at T2 with the best-fit method using the middle third of the labial and lingual surface as the reference area. To measure the volume of the canines, four boundary planes were constructed, and the differences in volume before and after orthodontic treatment were calculated.Results:The mean volume of tooth wear of the 224 canines was 2.0 mm³ after 35.5 months of orthodontic treatment. The volume of canine tooth wear was 2.3 ± 1.5 mm³ in male subjects and 1.9 ± 1.2 mm³ in female subjects. The mean wear of the upper right canines (2.4 ± 2.0 mm³) was significantly greater than that of the lower right canines (1.9 ± 2.6 mm³).Conclusions:Regional registration of teeth in 3D digital models is useful for quantitative evaluation of tooth wear in orthodontic patients. This method may also be used to assess treatment results in restorative dentistry.     

Effects of intraoral aging on surface properties of coated nickel-titanium archwires

Objective:To evaluate the effects of intraoral aging on surface properties of esthetic and conventional nickel-titanium (NiTi) archwires.Materials and Methods:Five NiTi wires were considered for this study (Sentalloy, Sentalloy High Aesthetic, Superelastic Titanium Memory Wire, Esthetic Superelastic Titanium Memory Wire, and EverWhite). For each type of wire, four samples were analyzed as received and after 1 month of clinical use by an atomic force microscope (AFM) and a scanning electronic microscope (SEM). To evaluate sliding resistance, two stainless steel plates with three metallic or three monocrystalline brackets, bonded in passive configuration, were manufactured; four as-received and retrieved samples for every wire were pulled five times at 5 mm/min for 1 minute by means of an Instron 5566, recording the greatest friction value (N). Data were analyzed by one-way analysis of variance and by Student''s t-test.Results:After clinical use, surface roughness increased considerably. The SEM images showed homogeneity for the as-received control wires; however, after clinical use esthetic wires exhibited a heterogeneous surface with craters and bumps. The lowest levels of friction were observed with the as-received Superelastic Titanium Memory Wire on metallic brackets. When tested on ceramic brackets, all the wires exhibited an increase in friction (t-test; P < .05). Furthermore, all the wires, except Sentalloy, showed a statistically significant increase in friction between the as-received and retrieved groups (t-test; P < .05).Conclusion:Clinical use of the orthodontic wires increases their surface roughness and the level of friction.     

Cephalometric Norms for Kuwaiti Adults: A preliminary study

PurposeTo establish for the first time cephalometric norms for adult Kuwaitis with normal class I occlusion according to ethnic group and gender, and to compare the findings to the previously published norms of the Caucasoid.Materials and methodsEight hundred adult Kuwaiti subjects were screened at two locations. The inclusion criteria were: Kuwaiti adults born to parents, and grandparents of pure Arab or Persian heritage; esthetically pleasing faces; angle class I molar and canine relationships; all permanent teeth present; irregularity index of less than 4 mm; and no history of orthodontic treatment or plastic surgery. Lateral cephalometric radiographs were taken by one investigator then traced and analyzed using twenty-nine angular, and linear measurements. Independent sample t-test was used to assess the inter-ethnic and the inter-gender differences. The results were then statistically compared to the norms of the Caucasoid.ResultsA total of 56 adult subjects were included. Several significant differences were noted between the Kuwaiti Arab and the Kuwaiti Persian ethnic groups. The most noteworthy differences were observed for the angles SNA and SNB and for the mean total lengths of the maxilla and mandible. When compared to the Caucasoid, statistically significant differences were noted in all mean dental and soft tissue measurements between the pooled Kuwaiti population and the Caucasoid.ConclusionThere are some fundamental variations in the craniofacial structure of Arabs, and Persians of the adult Kuwaiti population. These differences should be considered in larger future studies to establish clinical norms for orthodontic patients in Kuwait.     

Impact of pediatric obstructive sleep apnea on the development of Class II hyperdivergent patients receiving orthodontic treatment: A pilot study

Objectives:To conduct a pilot study to determine if the presence of obstructive sleep apnea (OSA) influences the orthodontic treatment outcome of Class II hyperdivergent patients receiving comprehensive orthodontic treatment.Materials and Methods:Patients between the ages of 12 and 14 who received orthodontic treatment at the Hospital of Stomatology, Wuhan University, China, were included in this study. Patients were divided into two groups: the OSA group and the control group, based on the outcome of pretreatment polysomnography findings and lateral cephalometric radiograph examination. Patients in the control group were matched with the OSA group for age, sex, ethnicity, weight, and height. Cephalometric measurements were used to record the skeletal and dental changes from before to after treatment. Data were analyzed using the t-test.Results:Twenty three OSA patients and 23 control patients were included. After comprehensive orthodontic treatment, the mandibular plane angle (SN-GoMe), articular angle (SArGo), sum of Jarabak angles (SUM) and the lower gonial angle (NGoMe) were found to increase significantly in the OSA group but remained unchanged or decreased slightly in the control group (P < .05). In the non-OSA group, the growth pattern became more horizontal. In contrast, in the OSA group the growth pattern became more vertical. Otherwise, similar treatment results were obtained for both groups in terms of sagittal change and occlusion.Conclusions:The presence of OSA in pediatric patients has a deleterious effect on the development of hyperdivergent malocclusions. Early diagnosis and management of pediatric OSA can affect the orthodontic treatment outcome of these patients.     

Impact of early extraction of the deciduous canine on relief of severe crowding:: Does it influence later orthodontic interventions?

ObjectivesTo explore whether there were any differences in orthodontic treatment need, treatment complexity, treatment time, or the number of visits between a group of children receiving early intervention (extraction of upper and lower deciduous canines) and an age- and condition-matched control group without intervention.Materials and MethodsPatient records and study casts in the late mixed or early permanent dentitions of 46 subjects (20 from the extraction group and 26 from the control group) of an earlier prospective longitudinal study were retrieved. Orthodontic treatment need and complexity were assessed by the index of complexity, outcome, and need (ICON). Statistical calculations were performed by t-test for parametric outcome variables (treatment time, number of visits, and orthodontic treatment need) and Fisher exact test for the categorical variable (tooth extractions).ResultsThere were no statistically significant differences between the groups in ICON scores of orthodontic treatment need (extraction group, mean score 59.8; control group, mean score 52.8), number of visits (mean of about 15 visits for both groups), or treatment time (extraction group, mean 21.5 months; control group, mean 20.3 months). The extraction of permanent teeth was more prevalent in the deciduous canine extraction group (59%) as compared with the control group (28%); however, this was not statistically significant (P = .07) but showed a tendency toward worsening the crowding and the future need of orthodontic extractions.ConclusionsEarly removal of deciduous primary canines will reduce neither the need for later orthodontic treatment nor its complexity, nor will it shorten the treatment time.     

Soft-tissue cephalometric norms for north Indian Mongoloids

IntroductionHarmonious facial esthetics and functional occlusion have long been recognized as the two most important goals of orthodontic treatment. The purpose of this study was: (1) To establish soft tissue cephalometric norms for Mongoloid tribes of north India using Holdaway analysis. (2) To study the sexual dimorphism in soft tissue cephalometric norms of this population. (3) To compare the norms obtained in this study with Holdaway norms.MethodsLateral cephalometric radiographs of 60 north Indian Mongoloid subjects (30 male, 30 female) in the age group of 18–25 years with normal occlusion and well balanced faces were used. The cephalograms were analyzed with Holdaway soft tissue cephalometric analysis. Unpaired t-test was used to compare results obtained for Mongoloid subjects with Holdaway norms and to determine sexual dimorphism.ResultsStatistically significant differences were found for nose prominence, superior sulcus depth, soft tissue subnasale to H-line, basic upper lip thickness, max incisor to upper lip, H-angle, lower lip to H-line and soft tissue chin thickness. In comparison of sexes, statistically significant differences were found for basic upper lip thickness, max incisor to upper lip and H-angle.ConclusionThese results show that the soft tissue facial profile of north Indian Mongoloid subjects and North-Europeans are different. These racial differences must be considered during diagnosis and treatment planning.     

Effectiveness of high irradiance for short-time exposures on polymerization of composite under metal brackets

Objective:To evaluate the effect of different curing modes available in a dental light-curing unit on degree of conversion (DC) of a composite photoactivated under a metal orthodontic bracket.Materials and Methods:The average irradiance and total energy delivered by three curing modes (standard, high, and extra power) of a multiwave LED unit (Valo Cordless, Ultradent Products, South Jordan, Utah) were measured using the longest time available for each mode (20, 4, and 3 seconds, respectively). Brackets (n = 3/group) were bonded to molar epoxy resin replicas using each curing mode. Mesiodistal sections, 0.5 mm thick, were assessed using an infrared spectrometer microscope. Spectra of composite beneath the brackets were sequentially collected using the mapping tool in near-infrared (NIR)-transmittance mode. Composite conversion was mapped between the mesial and distal edges of the bracket base using 400-μm steps for a total of 10 measurements per specimen. Data from irradiance and total energy were analyzed by one-way ANOVA, while data of DC were analyzed with two-way repeated measures ANOVA (α = 0.05).Results:The highest DC values were observed for standard power (mean 56%, P < .05), while no difference was observed between high (50%) and extra power (49%) modes. Regarding the site of measurement, higher DC was observed close to the bracket edges (52%, P < .05).Conclusions:The use of high irradiance for a short time slightly reduced the DC. The small magnitude of reduction suggests that use of a high irradiance protocol is a clinically valid approach when bonding metal brackets.     

Toothbrushing forces in children with fixed orthodontic appliances.

Abstract

The aim of this investigation was to determine whether toothbrushing forces are influenced by wearing fixed orthodontic appliances. Thirty children, (10 males, 20 females) with planned fixed appliance therapy and aged 10-15 years, were recruited to the study. No subject had previously worn an orthodontic appliance. At baseline, each subject brushed their teeth in their usual way, unsupervised. The toothbrush used was a purpose-designed electronic instrument that measured the force applied to the brush and transmitted force data by radio to a remote PC. After toothbrushing, subjects had orthodontic brackets fitted. Toothbrushing was repeated at 2 and 14 weeks after baseline, and brushing forces recorded. There were no significant differences between the measurements made at baseline and those made at 2 and 14 weeks. There were no differences between males and females in the forces used at any time point. It was concluded that toothbrushing forces are unaffected by placing fixed orthodontic appliances in children. The brushing forces recorded were comparable with those previously found by other investigators.     

Vitamin E supplementation reduces stress levels from orthodontic force in Wistar rats (Rattus norvegicus)

BackgroundOrthodontic tooth movement is mediated by the inflammation process. Inflammation induces pain and increases the level of cortisol hormone as it triggers stress. The aim of this research was to observe the effects of vitamin E (VE) supplementation in reducing stress levels from orthodontic force in Wistar rats (Rattus norvegicus).MethodsWistar rats (n = 56) were divided into two groups: group 1 as the control group, and group 2 as the experimental group (VE group). VE supplemented for 14 days prior application of the separator as an orthodontic force. Each group was divided into four subgroups (n = 7), corresponding to the duration in days that force was applied, i.e., 0, 1, 3, and 7 days. Stress were measured by cortisol levels, and inflammation were measured by interleukin-1 beta (IL-1β) levels in blood plasma.ResultsThe VE group had lower cortisol levels than the control group, and significant found on days 3 and 7 (p = 0.026 and p = 0.037). The cortisol level in the VE group decreased faster, beginning on day 1, whilst the control group occurred on day 3. Statistical analysis of IL-1β levels found insignificant differences between the two groups.ConclusionVitamin E helps reduce stress caused by orthodontic force due to tooth movement.     

Tooth sizes in nonsyndromic hypodontia patients

Objective:To evaluate and compare the sizes of teeth in mild and severe hypodontia patients with those of healthy controls.Materials and Methods:Dental casts of 154 patients with two or more congenitally missing teeth were obtained. Patients were divided into two groups according to severity of hypodontia. Group I (mild) consisted of 118 patients with two to five missing teeth. Group II (severe) consisted of 36 patients with six or more missing teeth. In addition, a control group was included, which consisted of 50 patients who had an Angle Class I jaw relationship and no missing teeth. Mesiodistal and labiolingual dimensions of the teeth were measured with a digital caliper on dental casts. The independent-samples t-test was used to evaluate the effect of gender on measurements. Intergroup differences for mesiodistal and labiolingual dimensions were evaluated with analysis of variance and post hoc Tukey tests.Results:Statistically significant differences were found between girls and boys with hypodontia in the mesiodistal dimension of the mandibular first premolar and the labiolingual dimension of the mandibular lateral incisor (P < .01). Mesiodistal and labiolingual width measurements of the teeth of hypodontia patients showed statistically significant differences compared with the control group (P < .05). Most teeth showed significant dimensional reductions in severe hypodontia compared with mild hypodontia (P < .05).Conclusions:The mesiodistal and labiolingual dimensions of teeth in both mild and severe hypodontia groups were smaller than those in control subjects. The reduction in size was more excessive in the severe hypodontia group. The teeth showing the greatest difference in tooth dimensions were the maxillary lateral incisor (in mesiodistal dimension) and the mandibular canine (labiolingual dimension).     

无托槽隐形矫治对非拔牙病例矫治疗效的临床研究

目的：应用美国正畸专科医师委员会OGS（Objective Grading System）客观评分系统,对无托槽隐形矫治器临床矫正效果进行评价。方法：选择60例20～25岁非拔牙矫治的错颌畸形患者,随机分成两组,实验组采用无托槽隐形矫治器,对照组采用自锁托槽矫治器。用ABO测量尺对矫治完成后的石膏牙模型和全景片分别进行测量,测量参数包括：牙齿排列整齐程度、邻牙边缘嵴高度差值、颊舌向倾斜度差值、矢状向咬合关系差值、咬合接触紧密度、覆盖异常程度、邻面接触紧密度及牙根成角。评分结果输入SPSS13．0统计软件包进行分析。结果：除上下后牙颊舌向倾斜角及咬合接触两项有统计学差异外,其余指标均无统计学差异。结论：无托槽隐形矫治器对错殆畸形非拔牙矫治病例临床矫治效果可达到自锁托槽矫治器矫治的效果。