Long-term profile attractiveness of patients with Class I and II malocclusion treated with and without extractions: A 35-year follow-up.

INTRODUCTION: The objective of this study was to compare the profile attractiveness in subjects treated with and without extractions after the long-term 35-year follow-up, according to laypeople, dentists, and orthodontists. METHODS: A total of 40 patients with Class I and II malocclusion were divided into 2 groups, according to the treatment protocol: extraction (E) group, extractions of 4 premolars (n = 24), with mean pretreatment (T1), posttreatment (T2), and long-term posttreatment (T3) ages of 13.13, 15.50 and 49.56 years, respectively. The mean treatment time (T2 - T1) was 2.37 years, and the long-term follow-up (T3 - T2) was 34.19. Nonextraction (NE) group (n = 16), with mean ages at T1, T2, and T3 of 13.21, 15.07, and 50.32 years, respectively. The mean (T2 - T1) was 1.86 years, and the (T3 - T2) was 35.25 years. Lateral cephalograms were used to perform profile facial silhouettes, and an online evaluation was performed by 72 laypeople, 63 dentists, and 65 orthodontists, rating the attractiveness from 1 (least attractive) to 10 (most attractive). The intragroup comparison was performed with the repeated measures analysis of variance and Tukey tests. Intergroup comparison was performed with t tests, 1-way analysis of variance, and Tukey tests. RESULTS: The E group had a longer treatment time than that of the NE group. In the pretreatment, posttreatment, and long-term posttreatment stages, the E and NE groups showed similar profile attractiveness. Laypersons and dentists were more critical than orthodontists. CONCLUSIONS: At long-term posttreatment follow-up, profile attractiveness was similar in patients treated with and without extractions.

Incisor irregularity and dental arch dimensions changes in subjects with different severity of anterior crowding: a 37-year follow-up.

BACKGROUND: Occlusal stability is one of the goals of orthodontic treatment, and keeping teeth aligned in the long term is a challenge for the orthodontist. This study aimed to compare the long-term incisors irregularity and dental arches dimensions changes in subjects treated with 4 premolar extractions with different pretreatment Little's irregularity index (LII). The knowledge of long-term outcomes is evidence-based information for the prognosis of future treatments. METHODS: In total, 41 treated subjects were divided into two groups according to mandibular Little irregularity value at pretreatment (mild or severe). The maxillary and mandibular LII, transversal, and longitudinal widths were assessed at pretreatment, posttreatment, and 37-year posttreatment. Chi-square and independent t tests were used for intergroup comparison. RESULTS: The groups presented similar behavior for all stages of maxillary and mandibular arch dimensions changes. Maxillary irregularity was corrected in both groups after treatment, and the alignment was acceptable in the long term. In the mild group, the mandibular incisor irregularity returned to pretreatment values in the long term. The mandibular LII increased in the severe group but did not return to pretreatment values in the long term. CONCLUSIONS: The mild crowding group presented proportionally more relapse of mandibular incisor irregularity than the severe crowding group in the long term. Even so, the correction of mild and severe crowding with the extraction of 4 premolars showed satisfactory results in the long term, even with the presence of maturational changes and relapse.

Occlusal changes in orthodontically treated subjects 40 years after treatment and comparison with untreated control subjects.

INTRODUCTION: The objective of this study was to compare the aging changes of the dental arches in orthodontically treated and untreated subjects after a 4-decade follow-up period. METHODS: This retrospective study analyzed 2 groups. The treated group comprised 29 patients (11 male, 18 female) presenting with Class I or Class II malocclusions orthodontically treated with extractions of 4 first premolars. Dental models taken at pretreatment (12.84 years), posttreatment (14.95 years), and long-term posttreatment (51.37 years) were evaluated. The untreated (control) group consisted of 22 untreated patients with dental models taken at 13.32, 17.82, and 60.95 years of age. The dental models were digitized, and the following variables were evaluated: Little irregularity index, intercanine, interpremolar and intermolar widths, arch length, arch perimeter, overjet, and overbite. Interphase comparison of the treated group was performed with repeated measures analysis of variance and Tukey tests. Intergroup comparisons were performed using t tests (P <0.05). RESULTS: Crowding was corrected with treatment but relapsed significantly in the long term. Intercanine width increased with treatment and decreased in the long term. Interpremolar and intermolar widths, arch perimeter, and length decreased with treatment and continued to decrease long-term posttreatment. Overjet and overbite were corrected with treatment and remained stable in the long term. From posttreatment to long-term posttreatment, a greater crowding increase was observed in the treated group than in the untreated group. The treated group demonstrated a greater decrease in mandibular intercanine and maxillary and mandibular interpremolar widths than the untreated sample. Overbite increased in the treated group and decreased in the untreated group. The multiple regression analysis showed that previous 4-premolar extractions orthodontic treatment is significantly associated with anterior crowding in the long term. CONCLUSIONS: In the long-term, the treated patients showed relapse of crowding and a decrease in arch form. Long-term changes of treated patients were different from untreated subjects. Relapse might have contributed to greater changes in incisor crowding and arch widths observed in the treated patients.

Two-phase orthodontic treatment of two different types of tooth transposition in the same patient.

Orthodontic treatment is thoroughly planned considering the patient's facial and dental characteristics, the main complaint, treatment time and the orthodontist's experience. Transposition is a form of ectopia, in which two adjacent teeth exchange positions in the dental arch. Transposition can be partial or complete. This article reports the treatment of a female patient with two kinds of tooth transposition managed in the mixed and permanent dentitions. A girl, aged eight years and three months, came to routine paediatric consultation with an ectopic permanent mandibular left lateral incisor in the mixed dentition. Radiographic analysis indicated partial transposition of the permanent mandibular left lateral incisor and canine (Md.L2.C), and development of a complete tooth transposition between the permanent maxillary right first pre-molar and canine (Mx.C.P1). The patient was treated in two phases. The first, in the mixed dentition, and the second, in the permanent dentition with a three-year follow-up between them. These challenging treatment approaches are described in detail, including the mechanics used. The key points of this treatment were early diagnosis of the ectopic mandibular lateral incisor, use of light forces and interphase patient follow-up. These determined the best time to start the second treatment phase, enabling achievement of aesthetic and functional outcomes, and the results remained stable one year after the end of orthodontic treatment.

Pretreatment dentoskeletal comparison between individuals treated with extractions in the 1970s and in the new millennium.

OBJECTIVE: This retrospective study aimed to compare the occlusal and dentoskeletal initial features of patients treated with four first premolar extractions in the 1970s and after 2000. MATERIALS AND METHODS: Group 70' was composed by 30 subjects with Class I malocclusion (mean age of 12.8 years, 10 male, 20 female) treated in the 1970s with four first premolar extractions and comprehensive orthodontic treatment. Group NM comprised 30 subjects with Class I malocclusion (mean age of 13.4 years, 13 male, 17 female) treated in the new millennium, similarly to Group 70'. Initial dental models and lateral cephalograms were digitized and measured using OrthoAnalyzerTM 3D software and Dolphin Imaging 11.0 software, respectively. Initial occlusal and dentoskeletal features were analyzed and compared. Intergroup comparison was performed using t tests (p < 0.05). Holm-Bonferroni correction for multiple comparison was applied. RESULTS: Group NM showed significantly greater maxillary and mandibular effective lengths and greater maxillary and mandibular incisor protrusion in comparison with Group 70'. Group NM presented a significantly greater lower anterior facial height. Group NM also showed significantly smaller nasolabial angle and protruded inferior lip. CONCLUSION: Patients with Class I malocclusion treated with four first premolar extractions in the new millennium present a greater degree of dental and labial protrusion, increased lower anterior facial height, and more acute nasolabial angle compared with patients treated similarly in the 1970s. Greater dental and labial protrusion determines first premolar extractions in the new millennium. CLINICAL RELEVANCE: Despite the decrease of tooth extraction frequency, four first premolar extractions may be justified in cases with severe dental and skeletal protrusions.

Comparison of torque expression in esthetic brackets.

BACKGROUND: The objective of this work is to test the null hypothesis that there is no difference in the torque expression among different esthetic brackets. MATERIAL AND METHODS: Five ceramic self-ligating brackets (In-Ovation C - GAC, Damon Clear-Ormco, QuicKlear-Forestadent, Click-It -TP Orthodontics, Clarity SL-3M Unitek) and 4 ceramic conventional brackets (Inspire Ice-Ormco, InVu Ceramic-TP Orthodontics, Ceramic Roth-Morelli, Clarity Metal-Reinforced Ceramic Bracket-3M Unitek) were selected. Metallic Damon MX self-ligating bracket (Ormco) was used as control. Third-order moments were measured at 12º, 24º and 36º using an archwire torsion device associated with a Universal Testing Machine (EMIC DL2000), with 0.019x0.025-inch stainless steel wire. Anova followed by Tukey tests were used for intergroup comparisons. RESULTS: In all tested angulations the Damon Clear bracket presented the highest torque expression, followed by Clarity, Clarity SL and Damon Mx brackets, with the worst torque expression shown by the InVu Ceramic bracket. The InVu Ceramic demonstrated the largest while the Damon Clear brackets demonstrated the smallest slot height and clearance. CONCLUSIONS: The null hypothesis was rejected since torque expression was different among the esthetic brackets evaluated. It was also concluded that the slot height is directly related to torque expression. Key words:Torque, orthodontic brackets, orthodontic appliances, incisor, ceramics.

Comparison of WALA ridge and dental arch dimensions changes after orthodontic treatment using a passive self-ligating system or conventional fixed appliance.

OBJECTIVE: To compare changes in WALA ridge and mandibular dental arch dimensions in orthodontic patients treated with a passive self-ligating system and conventional appliances. DESIGN: Original paper. SETTING: Orthodontic department at Inga University Center, Maringá, PR, Brazil. MATERIALS AND METHODS: Pretreatment (T1) and posttreatment (T2) dental casts of 60 patients with Class I malocclusion treated with slight to moderate crowding that were divided into two groups. Group 1: 30 patients treated with a passive self-ligating system, at a mean initial age of 17.68 years and mean treatment time of 2.31 years. Group 2: 30 patients treated with conventional appliances, at a mean initial age of 19.23 years and mean treatment time of 2.56 years. Measurements were taken using a digital caliper directly on pre and posttreatment dental casts to evaluate the transversal dimension behavior of the mandibular dental arch and the WALA ridge width. RESULTS: Self-ligating group presented an increase in WALA ridge width and mandibular transversal dimensions significantly greater than the conventional group, with the exception of intermolar cusp tip distance and intercanine WALA ridge. There was no statistically significant difference between the groups. There was also observed a significantly greater increase of the transversal buccal axis dimensions in the premolar area when compared to the WALA ridge increase in both groups. CONCLUSIONS: Treatment with a passive self-ligating system resulted in a significantly greater increase of the WALA ridge width and mandibular arch dimensions when compared to conventional appliance.

Aging of the normal occlusion.

OBJECTIVES: The aim of this study was to evaluate the qualitative occlusal changes in individuals with normal occlusion during a period of 47 years. MATERIALS AND METHODS: The sample comprised dental models of 20 subjects with normal occlusion (8 males; 12 females) taken at 13.2 years (T1) and 60.9 years of age (T2). The occlusal features were evaluated with the objective grading system (OGS) and with the six keys to normal occlusion (SKNO). The subjects also answered a questionnaire on the aesthetic and occlusal self-perception at T2. Comparisons from T1 to T2 were performed with paired t- and McNemar tests (P less than 0.05). RESULTS: OGS analysis showed a significant improvement in the marginal ridge levelling and tooth buccolingual inclination. There was a significant deterioration of the antero-posterior occlusal relationship from T1 to T2. Subjects without tooth loss showed a dental alignment worsening between time points. The marginal ridges, buccolingual inclination, and interproximal contacts improved. The SKNO analysis showed a significant deterioration of the maxillary second molars buccolingual inclination and an improvement of the maxillary second molar angulation. All patients were satisfied with their smiles, and 60 per cent of the subjects had no complaints. Dental crowding caused dissatisfaction in 35 per cent of the sample. LIMITATIONS: A limitation of this study was the high prevalence of tooth loss in the sample from T1 to T2. Only 30 per cent of the subjects had no tooth loss in T2. CONCLUSIONS: The aging process slightly deteriorates some occlusal features of individuals with normal occlusion. However, most individuals were satisfied with their aesthetics and occlusal comfort at the sixth decade of life.

Relapse of anterior crowding 3 and 33 years postretention.

INTRODUCTION: The aim of this study was to evaluate the relapse of occlusal characteristics and maxillary and mandibular anterior crowding 3 and 33 years postretention. METHODS: The sample comprised 28 patients, 15 Class I and 13 Class II, treated with 4 premolar extractions, with a mean initial age of 12.72 years (SD, 0.99), a mean final age of 14.74 years (SD, 1.26), and a mean treatment time of 2.02 years (SD, 0.66). The mean short-term postretention age was 20.15 years (SD, 1.34), and the mean long-term postretention age was 49.40 years (SD, 4.54). The mean time of short-term postretention evaluation was 3.70 years (SD, 0.87) and the mean long-term postretention evaluation was 32.95 years (SD, 4.31). The maxillary and mandibular irregularity indexes were assessed on the initial, final, short-term, and long-term postretention stage dental casts. Peer Assessment Rating and the Little indexes were compared among the 4 stages by repeated measures analysis of variance and Tukey tests. RESULTS: Peer Assessment Rating index and maxillary anterior crowding were significantly improved with treatment, had significant relapses in the short term, and a slight and not statistically significant increase from short-term to long-term postretention evaluation. The mandibular irregularity index significantly decreased with treatment, and then significantly and progressively increased in the postretention stages. CONCLUSIONS: The occlusal characteristics and maxillary anterior crowding had significant relapses in the short term and remained stable from the short-term to the long-term postretention stages. Mandibular anterior crowding significantly decreased with treatment, showed a significant relapse in the short term, and continued to significantly increase in the long-term postretention stage.

Treatment of a Class II Malocclusion with Deep Overbite in an Adult Patient Using Intermaxillary Elastics and Spee Curve Controlling with Reverse and Accentuated Archwires.

This paper aimed to describe the orthodontic treatment of an adult patient with the following characteristics: asymmetric Class II malocclusion, left subdivision, mandibular midline shifted to the left, mild mandibular anterior crowding, excessive overbite, 4-mm overjet, and a brachycephalic facial pattern. A 31-year-old male patient, treated with fixed preadjusted appliance with Roth prescription, with leveling and alignment NiTi archwire sequence. To correct the asymmetric Class II malocclusion, midline shift as well the overjet and overbite, intermaxillary elastics and accentuated and reversed stainless steel archwires were used, respectively. The posttreatment results showed a Class I molar relationship, as well the overjet and overbite correction. These results could be achieved due to a correct treatment plan and so to the patient cooperation.

External root resorption with the self-ligating Damon system-a retrospective study.

BACKGROUND: The aim of this study was to compare the degree of external apical root resorption (EARR) in patients treated with self-ligating Damon appliances and with conventional preadjusted appliances. METHODS: The sample comprised 52 patients, divided into two groups. Group 1 consisted of 25 patients treated with self-ligating Damon appliances, with an initial age of 16.04 years, final age of 18.06 years, and treatment time of 2.02 years. Group 2 consisted of 27 patients, treated with conventional preadjusted appliances, with an initial age of 16.77 years, final age of 18.47 years and treatment time of 1.70 years. The groups were matched regarding the initial and final ages, treatment time, type of malocclusion, and treatment protocol without extractions. Root resorption was evaluated on periapical radiographs of the maxillary and mandibular incisors at the end of orthodontic treatment with the scores of Levander and Malmgren. Intergroup comparisons of root resorption were performed with Mann-Whitney tests. RESULTS: No significant difference in the degree of root resorption between the two groups was found. CONCLUSIONS: Similar degrees of resorption can be expected after non-extraction treatment with Damon self-ligating or conventional preadjusted appliances.

Maxillary anterior alignment stability in Class I and Class II malocclusions treated with or without extraction.

OBJECTIVE: To compare the postretention stability of maxillary incisors alignment in subjects with Class I and II malocclusion treated with or without extractions. MATERIALS AND METHODS: The sample comprised 103 subjects with initial maxillary anterior irregularity greater than 3 mm and was divided into four groups: group 1 comprised 19 patients with Class I malocclusion treated with nonextraction (mean initial age = 13.06 years); group 2 comprised 19 patients with Class II malocclusion treated with nonextraction (mean initial age = 12.54 years); group 3 comprised 30 patients with Class I malocclusion treated with extractions (mean initial age = 13.16 years); group 4 comprised 35 patients with Class II malocclusion treated with extractions (mean initial age = 12.99 years). Dental casts were obtained at three different stages: pretreatment (T1), posttreatment (T2), and long-term posttreatment (T3). Maxillary incisor irregularity and arch dimensions were evaluated. Intergroup comparisons were performed by one-way analysis of variance followed by Tukey tests. RESULTS: In the long-term posttreatment period, relapse of maxillary crowding and arch dimensions was similar in all groups. CONCLUSION: Changes in maxillary anterior alignment in Class I and Class II malocclusions treated with nonextractions and with extractions were similar in the long-term posttreatment period.

Class III Malocclusion Surgical-Orthodontic Treatment.

The aim of the present case report is to describe the orthodontic-surgical treatment of a 17-year-and-9-month-old female patient with a Class III malocclusion, poor facial esthetics, and mandibular and chin protrusion. She had significant anteroposterior and transverse discrepancies, a concave profile, and strained lip closure. Intraorally, she had a negative overjet of 5 mm and an overbite of 5 mm. The treatment objectives were to correct the malocclusion, and facial esthetic and also return the correct function. The surgical procedures included a Le Fort I osteotomy for expansion, advancement, impaction, and rotation of the maxilla to correct the occlusal plane inclination. There was 2 mm of impaction of the anterior portion of the maxilla and 5 mm of extrusion in the posterior region. A bilateral sagittal split osteotomy was performed in order to allow counterclockwise rotation of the mandible and anterior projection of the chin, accompanying the maxillary occlusal plane. Rigid internal fixation was used without any intermaxillary fixation. It was concluded that these procedures were very effective in producing a pleasing facial esthetic result, showing stability 7 years posttreatment.

Systematic literature review: influence of low-level laser on orthodontic movement and pain control in humans.

OBJECTIVE: The purpose of this study was to systematically review the literature to check the influence of low-level laser (LLL) on orthodontic movement and pain control in humans, and what dose ranges are effective for pain control and increased speed of orthodontic movement. METHODS: Computerized and manual searches were conducted up to January 4, 2014 for clinical studies that addressed these objectives. The selection criteria required that these studies (1) be prospective controlled clinical trials (CCT) and randomized clinical trials (RCT); (2) only use LLL in both infrared and visible red wavelengths, a laser with emission of constant wave; (3) have all main parameters of dose described, or at least conditions for calculation of the energy, in Joules; and (4) be published in Portuguese, English, or Spanish and be meta-analyses. RESULTS: Seven studies met the eligibility criteria for orthodontic movement/LLL and 11 studies met the inclusion criteria for analgesia/LLL, totaling 18 prospective randomized studies that were selected for detailed analysis. The most common and effective energy input was the interval of 0.2-2.2 J per point/2-8 J per tooth at a frequency of application 1-5 days per month to accelerate the orthodontic movement. For pain control, the recommended energy per points varied from 1-2 J when only one tooth was irradiated to 0.5-2.25 J per point when all teeth in the dental arch were irradiated. CONCLUSIONS: LLL seems to have a demonstrated efficacy, but further studies are warranted to determine the best protocols with regard to energy and frequency.

Nasolabial angle at rest and upon smiling.

PURPOSE: The objectives of this study were 1) to determine the mean and SD of the nasolabial angle (NLA) and the linear measure pronasale (Prn)-A' at rest and upon smiling and 2) to determine the difference between smile and rest in participants with normal occlusion and facial harmony. MATERIALS AND METHODS: The sample consisted of 40 white Brazilian participants (20 of each gender) aged 20 to 30 years and with normal occlusion, a pleasant profile, and facial harmony. The measures NLA and Prn-A' were analyzed in profile photographs at rest and during smile, with a millimeter ruler in front of the profile during use of the Dolphin software. The statistical analysis included dependent t tests to compare the rest and smiling variables. RESULTS: The mean of the NLA at rest was 104.93°; it was 110.67° during smile; and the difference between them was statistically significant, with a mean of 5.74°. The mean of the linear variable Prn-A' at rest was 23.25 mm, whereas during smile it was 24.04 mm, and the difference between them was statistically significant, with a mean of 0.79 mm. CONCLUSIONS: The variability in the NLA and Prn-A' at rest and upon smiling was found to be significant in a normal sample, and it should be considered as a diagnostic tool in the treatment planning for sagittal dentoskeletal deformities.

Longitudinal stability of rapid and slow maxillary expansion.

OBJECTIVE: The aim of this retrospective study was to compare the longitudinal stability of two types of posterior crossbite correction: rapid maxillary expansion (RME) and slow maxillary expansion (SME). METHODS: Study casts of 90 adolescent patients were assessed for interdental width changes at three different periods: pretreatment (T1), post-treatment (T2) and at least, five years post-retention (T3). Three groups of 30 patients were established according to the treatment received to correct posterior crossbite: Group A (RME), group B (SME) and group C (control- Edgewise therapy only). After crossbite correction, all patients received fixed edgewise orthodontic appliances. Paired t-tests and one-way ANOVA were used to identify significant intra and intergroup changes, respectively (P < 0.05). RESULTS: Except for intercanine distance, all widths increased in groups A and B from T1 to T2. In the long-term, the amount of relapse was not different for groups A and B, except for 3-3 widths which showed greater decrease in group A. However, the percentage of clinically relapsed cases of posterior crossbite was similar for rapid and slow maxillary expansion. CONCLUSION: Rapid and slow maxillary expansion showed similar stability in the long-term.

Comparative cephalometric study of Class II malocclusion treatment with Pendulum and Jones jig appliances followed by fixed corrective orthodontics.

OBJECTIVE: The purpose of this study was to cephalometrically compare the skeletal and dentoalveolar effects in the treatment of Class II malocclusion with Pendulum and Jones jig appliances, followed by fixed corrective orthodontics, and to compare such effects to a control group. METHODS: The sample was divided into three groups. Group 1: 18 patients treated with Pendulum, Group 2: 25 patients treated with Jones jig, and Group 3: 19 young subjects with untreated Class II malocclusions and initial mean age of 12.88 years. The chi-square test was applied to assess severity and gender distribution. Groups 1 and 2 were compared to the control group by means of the one-way ANOVA and Tukey tests in order to differentiate treatment changes from those occurred by craniofacial growth. RESULTS: There were no significant changes among the three groups with regard to the components of the maxilla and the mandible, maxillomandibular relationship, cephalometric and tegumental pattern. Buccal tipping of mandibular incisors was significantly greater in the experimental groups and increased mesial angulation of the maxillary second molars was found in the Jones jig group. In the experimental groups, dental relationship, overbite and overjet were corrected. CONCLUSIONS: It can be stated that the distalization achieved its purpose of correcting the Class II.

Influence of treatment including second molars on final and postretention molar angulation.

OBJECTIVE: Evaluate axial mesiodistal inclinations of the mandibular molars in orthodontically treated cases, analyzing whether inclusion of second mandibular molars in treatment mechanics has any influence on final and postretention molars angulations. METHODS: The sample comprised 150 panoramic radiographs of 50 patients. Patients were treated with extraction of four first premolars and divided into 2 groups: Group 1 comprised 25 subjects without inclusion of mandibular second molars during orthodontic treatment, whereas Group 2 comprised 25 subjects with inclusion of mandibular second molars. Panoramic radiographs at three observation times were evaluated: pretreatment, posttreatment and postretention. The statistical analysis included one-way analysis of variance (ANOVA) for intragroup evaluation and independent t-tests for intergroup comparisons. RESULTS: Intragroup analysis demonstrated significant uprighting of mandibular first and second molars during treatment in Group 2, which remained stable during the postretention stage. Intergroup comparison demonstrated that Group 2 presented first and second molars significantly more uprighted in relation to Group 1 in both post-treatment and postretention stages. CONCLUSIONS: It was concluded that inclusion of mandibular second molars in the orthodontic mechanics is relevant not only to correct the angulation of these teeth, but also to aid mandibular first molars uprighting.