v. 17, no. 6
Dental Press Journal of Orthodontics – ISSN 2176-9451
Dental Press J. Orthod.
v. 17, no. 6
November / December
Crossbite: Expansion of authors in scientific articles
In these times of ?scientometrics?, it seems prudent to ponder the number of authors that should together compose a scientific article. Taking it one step further, I?d like to address the cross-reverberation that results from the expansion of authorship without effective author participation, and its impact on the neoformation of the morals and ethics of our young researchers.
Just recently, an article with eight authors was submitted to the Dental Press Journal of Orthodontics (DPJO). The number in itself is elusive and one should not jump to conclusions. It would be prejudicial ? pure and simple ? to do so. It is common for journals such as Nature and Science, to cite two of the most prestigious journals worldwide, to publish articles with dozens and dozens of authors. It would be naive, however, to deny that the need to publish, compelled by competition, has led some scientists to become oblivious to science as the foundation of truth, and even less so to ethics as philosophy. This question seems too important to overlook, too challenging to avoid.
The article in question, submitted to DPJO, presented data on a rather basic laboratory test, and nothing could justify the overwhelming number of authors. In itself, the content of the article precluded its publication, and the excessive number of authors caused atresia in the editor?s confidence regarding the purposes of the study. The article was submitted by a young researcher and it seems logical to believe that he may have been hard pressed to expand the list of author names to include some of his tutors. ?Example is always more effective than theory,? wrote Englishman Samuel Johnson. Not only that, but the young man saw it fit to expand even further the authorship and added the names of some of his class(?mates?).
Could this need for scientific output be a condition somatically imposed by our culture? In seeking to clarify the issue, I reviewed the original articles published in the two most prestigious orthodontic journals worldwide in the year 2012. I perceived that the articles published by Brazilians include on average one author more than articles published by authors from other countries (p < 0.01). The average ? median, to be exact ? Brazilian articles have five authors, whereas other nationalities exhibit a median of four per article.
Why is it that articles published by Brazilian orthodontists have, on average, one extra author? One plausible explanation could be the difficulties involved in writing in the English language. It would make sense, therefore, to include an author with in-depth knowledge of English. This explanation falls apart when we realize that the educational level of Brazilian orthodontists who publish in prestigious scientific journals is too high to regard the English language as a major barrier. Another thesis that might justify this phenomenon has to do with the increasing number of studies from non-English speaking countries published in these journals. Therefore, many researchers in Turkey, Japan, China and some European countries would purportedly encounter difficulties to publish in the language of Shakespeare.
The inclusion of authors who actually did not contribute anything to a given study is a breach of ethics, as well as unfair competition to virtuous professionals. Nevertheless, it would be naive to believe that this practice affects Brazilian researchers exclusively. In reviewing the two leading international journals of orthodontics I found an article with nine authors. It pertained to an in vitro assay to examine bond strength using different etching agents. In my view, nothing justifies such a large number of authors.
This issue permeates orthodontics. Even first-rate journals are not immune to this problem. In 2002, one out of every ten authors of articles published in the British Medical Journal (BMJ), and one out of five authors of the Annals of Internal Medicine comprised authorship credit without proper justification.1 In the latter, it is estimated that 60% of published articles had at least one ?fake? author.
According to the International Committee of Medical Journal Editors (ICMJE), someone should only be considered ?author? if their intellectual contribution is substantial.2 Some journals request and publish information about the contributions of each author. Editors have been strongly encouraged to implement a policy of identifying the person responsible for the integrity of the work, and the role each author plays in the study. Journals such as Nature, BMJ, The Lancet, PLoS and JAMA have followed these guidelines. In dentistry as well as orthodontics, this is a little known practice.
In early 2012, the DPJO launched the policy of identifying each author in the studies submitted to it. Today, the submission system accepts up to four authors. This does not prevent the corresponding author from including more names, but it does require a statement to the editor about the role of each researcher in the study. This new policy has yielded impressive results, and the overblown expansion referred above is showing signs of constriction. In recent years (2010 and 2011), approximately 46% of the articles published in DPJO had five or more authors. Almost ten months after this adjustment only 7% of the corresponding authors justified the inclusion of more than four authors.
The International Committee of Medical Journal Editors (ICMJE) determines that all those who have collaborated in a study but do not meet the criteria for authorship be listed in the acknowledgments section. People who have provided purely technical help, text revision, or department colleagues who have provided generic support should only be included in this section. In my editorials, I relied on the help of my brother, a thoracic surgeon who also boasts considerable skill in crafting eloquent words in a concise fashion. My ?ghost-writer? spent part of his scant free time helping me tackle the difficult task of producing a clearer, purposeful and polished text. In this editorial, for example, he played a primary role mitigating the inherent roughness of the subject. It so happens that some wounds might be exposed. Therefore, surgical treatment in the choice of words could render the predicament less unpleasant, since pain seems inevitable. For this ?textoplasty? ? although not strictly a coauthorship ? failing to thank him would be a gesture of ingratitude.
SELF-LIGATING BRACKETS DO NOT MAKE THE ORTHODONTIC TREATMENT FASTER
Nowadays, a question remains among orthodontists: Would self-ligating brackets be able to increase the efficiency of orthodontic treatment and make it faster? Although it may seem paradoxical to think that the connection of brackets will interfere with the biology of tooth movement, the orthodontic materials industries keep this flame lit. While searching for an answer, Chinese researchers compared the treatment time, the results achieved and anchorage loss in patients treated with self-ligating and conventional brackets.1 The results showed no difference regarding the time and loss of anchorage in patients treated using brackets with different ligating systems.
Occlusal trauma can not be compared to orthodontic movement or Occlusal trauma in orthodontic practice and V-shaped recession
Occlusal trauma. Occlusion. Gingival recession. Gingiva abfraction. Orthodontics.
The mechanisms of tissue changes induced by occlusal trauma are in no way comparable to orthodontic movement. In both events the primary cause is of a physical nature, but the forces delivered to dental tissues exhibit completely different characteristics in terms of intensity, duration, direction, distribution, frequency and form of uptake by periodontal tissues. Consequently, the tissue effects induced by occlusal trauma are different from orthodontic movement. It can be argued that occlusal trauma generates a pathological tissue injury in an attempt to adapt to new excessive functional demands. Orthodontic movement, in turn,performs physiological periodontal bone remodeling to change the position of the teeth in a well-planned manner, eventually restoring normalcy.
An interview with Carlos Flores-Mir
Marcio Rodrigues de Almeida
The action of corticosteroids on orthodontic tooth movement: A literature review
Evaluation of plasticity and radiopacity of elastic separators by means of traction tests and radiography
In order to obtain an adequate orthodontic banding, it is essential a satisfactory interdental separation. Elastic separators have been used routinely for that. However, clinically it has been observed that if the elastic separators are placed subgingivally, they can cause bone resorption and loss of gingival and periodontal fibers. For this reason, the elastic separators should be radiopaque, so they can be localized through a periapical radiograph. The aim of this study was to analyze the plasticity and radiopacity of elastic separators used in orthodontic clinic. Six trademarks of modular and extruded elastic separators were evaluated (Abzil, Dentaurum, GAC, American Orthodontics, GH and Morelli ? blue and green types). Ten sets from each brand were submitted to tensile test, wherein the inner diameter was stretched three times in a universal testing machine. Before and after this test, the elastic separators were evaluated in a trinocular microscope and images were captured by a digital camera in order to measure the deformation of the specimens. For the analysis of radiopacity, periapical radiographs from elastic separators were taken conventionally. The results showed that the extruded elastics separators did not demonstrate plastic deformation, unlike the modular separators, which Morelli blue and Abzil presented higher deformations (10.75% and 8.75%, respectively). Moreover, only the extruded separators from America Orthodontics and GH showed radiopacity, as well as the modular separators from Abzil, Dentaurum and GAC. Based on the plasticity and radiopacity presented by elastic separators, the extruded separators from American Orthodontics and GH and modular separators from GAC and Dentaurum were indicated to clinical proposes.
In vitro corrosion of metallic orthodontic brackets: Influence of artificial saliva with and without fluorides
Many nickel-free and reduced nickel content metallic brackets have been proposed, due to nickel sensitivity presented by some patients in orthodontic clinic. However, few studies have assessed the behavior of these brackets in the oral cavity, composed of many chemical substances, proteins and microorganisms at different temperatures, which often results in corrosion of metallic alloys. Therefore, the aim of this study was to evaluate the ?in vitro? corrosion resistance of nickel-free and reduced nickel content metallic brackets immersed in artificial saliva with and without fluoride by means of scanning electron microscopy. Seventeen brackets for each trademark were analyzed, as follows: nickel-free brackets (Nickel-Free Morelli ? Morelli, Sorocaba, Brazil), reduced nickel content stainless steel brackets with titanium nitride coating (Morelli Golden Line ? Morelli, Sorocaba, Brazil), cobalt-chromium brackets (TP-Orthodontics, La Porte, United States) and titanium brackets (Dentaurum ? Ispringen, Germany). These brackets were immersed in artificial saliva at 37°C for 7, 9 and 11 weeks (respectively groups 1, 2 and 3). In the group 4, the brackets were immersed in artificial saliva and fluoride for 11 weeks. For each group, four brackets were evaluated. The control group was comprised only one no-immersed bracket. The corrosion of the brackets was analyzed qualitatively by scanning electron microscopy (SEM), with increases from 200 to 500 times. Furthermore, the chemical composition of surface residues on the brackets was evaluated by SEM associated with an energy dispersive x-ray analyzer (EDS). Also the amount of ions released in the artificial saliva was measured by atomic absorption spectrophotometry. The results showed that all brackets demonstrated lower corrosion resistance in the fluoride presence. Titanium and nickel-free brackets presented good corrosion resistance. In titanium nitride coating brackets, oxides were verified on surface, probably due to defects resulting from the titanium nitrite coating. The lowest corrosion resistance was observed in cobalt-chromium brackets, probably because the weld between the base and body of these brackets and the heat treatment of this alloy. So, it was verified oxides and cobalt, chromium and silver on surface of cobalt-chromium brackets. On the other hand, there were no clear signals of the release of ions in all evaluated solutions. Thus the presence of fluoride promoted higher corrosion in all brackets. Despite the low corrosion resistance presented by cobalt-chromium brackets, there was no significant release of ions in all solutions of evaluated brackets.
Longitudinal study of mandibular behavior in Class I subjects with vertical and horizontal growth
The pattern of craniofacial growth may determine mandibular rotations during the growth and development of the craniofacial complex, which affects directly the orthodontic planning, treatment and prognosis. The aim of this study was to analyze and compare the mandibular growth longitudinally in Class I patients with horizontal or vertical pattern. It was the lateral cephalograms of 20 patients from the Burlington Growth Centre, University of Toronto, Canada. These patients were divided into two groups (n=10), depending on the initial growth pattern. The craniofacial growth was assessed at ages 9, 12 and 21 years. The lateral cephalograms were properly traced, and cephalometric measurements were performed by Dentofacial Planner Plus 2.1. Differences between groups were evaluated using independent t test (p < 0.05). The results demonstrated more retrognathic position of the mandible in dolichofacial patients; however, the same amount of mandibular growth (Co-Gn) was observed in both groups in the evaluated period. On the other hand, it was verified no changes at SN.GoMe angle in dolichofacial patients, in contrast to the brachyfacial patients, in which it was noted a gradual decrease of this angle, showing a counterclockwise mandibular rotation during craniofacial growth and development.
In vitro force delivery of nickel-titanium superelastic archwires in vertical displacement
Corrective orthodontics. Orthodontic archwires. Tooth movement.
Objective: The purpose of this study was to evaluate the force delivered by different superlastic nickel-titanium wires during vertical displacement, in order to determine whether their stress release meets the criteria for constant and light forces that are usually accredited to these archwires.
Method: Ten samples of 6 brands of 0.016-in archwires (Ormco, GAC, Morelli, TP, American Orthodontics e Rocky Mountain) were tested in a complete metal model using Dynalock brackets (3M Unitek?). In the canine position, there was a sliding bracket connected to a pole. This set was related to a load cell of 0.5 kg attached to a universal testing machine (Autograph AG-199kNG, Shimadzu). The crosshead speed was 0.5 mm/min and the maximum displacement was 1.0 mm. The model was submerged in temperature-controlled water. The results were analyzed by ANOVA (p < 0.05), using the software SAS System 8.02, Cry, NC, USA.
Results: The TP archwire had the lowest force throughout the test, although the final force was high (277.91 g). The Rocky Mountain archwire had the highest force release (455.41 g).
Conclusion: The different brands of wires tested in this study failed in delivering low and constant forces as expected from superlastic nickel-titanium wires. The forces were extremely heavy for a vertical tooth movement.
Cephalometric effects of the use of 10-hour Force Theory for Class II treatment
Angle Class II malocclusion. Corrective orthodontics. Extraoral traction appliances.
Objective: This study aimed to evaluate the cephalometric effects promoted by the orthodontic treatment of Class II malocclusion patients with the use of the 10-Hour Force Theory, that consists in the use of fixed appliances with 8 hours a day using a cervical headgear appliance and 16 hours a day using Class II elastics, 8 hours on the first mandibular molar and 8 hours in the second mandibular molar.
Methods: Sample comprised 31 patients with mean initial age of 14.90 years, final mean age of 17.25 years and mean treatment time of 2.35 years. The lateral cephalograms in pre-treatment and post-treatment stages were evaluated. Evaluation of cephalometric changes between initial and final treatment phases was performed by paired t test.
Results: The cases treated with the 10-Hour Force Theory presented a slight restriction of anterior displacement of the maxilla, increase in the effective length of the mandible, significant improvement of the maxillomandibular relationship, significant increase in anterior lower face height, distal tipping of the maxillary premolar crowns, extrusion and distal tipping of the roots of maxillary molars, significant proclination and protrusion of mandibular incisors, significant extrusion and mesialization of mandibular molars, besides a significant correction of the molar relationship, overjet and overbite.
Conclusion: The use of the 10-Hour Force Theory in treatment of Class II malocclusion provided satisfactory results.
Stability of bimaxillary surgery on Class III malocclusion treatment
Angle Class III malocclusion. Osteotomy. Le Fort osteotomy.
Objective: To evaluate the stability of bimaxillary surgery in patients with skeletal malocclusion, with the use of rigid internal fixation.
Methods: Lateral cephalograms from 20 patients, 11 males and 9 females, mean age of 26 years and 1 month, were evaluated before surgery, immediately post-operative and at least 6 months after surgery. Nineteen cephalometric measurements were evaluated, and the results were statistically analyzed by means of the Student?s t test and the Kruskal-Wallis test.
Results: The Le Fort I maxillary advancement surgery showed almost no relapse. There was lack of stability of mandibular setback, with relapse of 37.33% on point B, due to counterclockwise rotation of the mandible between post-operative periods, occurred by better intercuspation after surgery and muscle adaptation. The results showed the same tendencies for both genders.
Conclusion: It was concluded that on the bimaxillary surgery treatment of Class III malocclusion, the maxillary surgery was very stable, but the mandibular setback recurred. No statistical differences were found in surgical stability between genders.
Evaluation of the stability of open bite treatment using a removable appliance with palatal crib combined with high-pull chincup
Open bite. Angle Class I malocclusion. Orthodontics.
Objective: The aim of this prospective study was to cephalometrically analyze the stability of dentoalveolar and skeletal changes produced by a removable appliance with palatal crib associated to high-pull chincup in individuals with anterior open bite treated for 12 months, and compare them to individuals with similar malocclusion and age, not submitted to orthodontic treatment, also followed for the same period.
Methods: Nineteen children with a mean age of 9.78 years old treated for 12 months with a removable appliance with palatal crib associated with chincup therapy were evaluated after 15 months (post-treatment period) and compared with a control group of 19 subjects with mean age of 9.10 years with the same malocclusion that was followed-up for the same period. Seventy-six lateral cephalograms were evaluated at T1 (after correction) and T2 (follow-up) and cephalometric variables were analyzed by statistical tests.
Results: The results did not show significant skeletal, soft tissue or maxillary dentoalveolar changes. Overall, treatment effects on the experimental group were maintained at T2 evaluation with an increase of 0.56 mm in overbite. Overjet and maxillary incisors/molars position (vertical and sagittal) remained essentially unchanged during the study period. Only mandibular incisors showed significant changes (labial inclination and protrusion) compared to control group.
Conclusions: Thus, it can be concluded that the early open bite treatment with a removable appliance and palatal crib associated with high-pull chincup therapy provided stability of 95%.
Evaluation of occlusal factors in patients with temporomandibular joint disorder
Dental occlusion. Malocclusion. Temporomandibular joint dysfunction syndrome.
Objective: The aim of this study was to determine the prevalence and the relation between the main occlusal factors and the temporomandibular disorder (TMD).
Methods: We analyzed 100 patients (50 diagnosed with TMD and 50 asymptomatic volunteers, control group) through a questionnaire that classified TMD as absent, mild, moderate and severe. Then, an evaluation was made of intraoral occlusal factors: Absence of posterior teeth, wear facets, overjet, overbite, open bite, posterior crossbite, sagittal relationship (Class I, II and III), centric relation discrepancy for maximum intercuspation, anterior guidance and balancing occlusal interference. The c2 examined the association between TMD and considered occlusal variables.
Results: The prevalence of studied occlusal factors was higher in patients with moderate and severe TMD. Statistically significant results were found on: Absence of five or more posterior teeth, overbite and overjet greater than 5 mm, edge-to-edge bite, posterior crossbite, Class II and III, the absence of effective anterior guide and balancing side interferences.
Conclusions: Indeed, it is concluded that there is a relationship between TMD and occlusal factors, however it can not be told to what extent these factors are predisposing, precipitating or perpetuating the disease. Therefore, despite its multifactorial etiology, one can not neglect the occlusal analysis of these patients.
Influence of treatment with and without extractions on the growth pattern of dolichofacial patients
Angle Class II malocclusion. Vertical dimension. Tooth extraction.
- Objective: The objective of this retrospective study was to compare, by means of lateral cephalograms, the facial growth pattern changes due to the treatment with and without extractions of four first premolars in dolichofacial individuals.
- Methods: Groups 1 and 2 were constituted of 23 dolichofacial patients each, with Class II malocclusion, division 1 and initial age average of 12.36 and 12.29 years, respectively. Patients from Group 1 were treated without extractions and Group 2 was treated with extraction of the four first premolars, given that both used occipital headgear. Groups were compatibilized according to age, treatment period, gender and malocclusion severity. The t test was applied for intergroups comparison.
- Results: Most variables (SN.PP, SN.Ocl and FMA) did not present statistically significant difference between groups.
- Conclusion: Although the treatment with extractions tend to reduce the mandibular plane angle (SN.GoGn) and the facial axis (NS.Gn), the analyzed treatment protocols did not affect in a clinically relevant way the facial growth pattern.
Class II malocclusion with deep overbite: A sequential approach
Angle Class II malocclusion. Extraoral traction appliances. Tooth movement.
Objective: The aim of this case report was to evaluate the results of deep overbite correction by the segmented arch technique.
Methods: The first stage of the treatment was performed with this technique to intrude incisors and canines. A maxillary transpalatal bar and a mandibular lingual arch using 0.051-in archwire were employed associated to a facial bow, anchored primarily with occipital pull and, after molar relationship correction, changed to high pull.
Results: Upper incisors presented a great amount of intrusion and some palatal root inclination as programmed in the treatment plan. The skeletal mandibular response was favorable to achieve profile balance. Periapical radiograph showed rounded apex of incisor roots, expected in any orthodontic intrusion movement.
Conclusion: The clinical results present the successful approach to deep overbite malocclusion.
Relation between agenesis and shape anomaly of maxillary lateral incisors and canine impaction
Incisors. Canine. Agenesis.
Objective: The purpose was to obtain information about the relation between agenesis and shape anomaly of maxillary lateral incisors and canine impaction.
Methods: Seventy-three patients with canine impaction and 73 control patients, without canine impaction, were evaluated. The mesiodistal distances of the maxillary lateral incisors adjacent to the impacted canines and the correspondent mandibular lateral incisors were measured. The adjacent lateral incisors were classified in: 1 - absent, 2 - small, 3 - peg-shaped, 4 - standard.
Results: The results showed that among the patients with impacted canines, there were 21 anomalous teeth (small and peg-shaped) and among the control patients there were only three small and peg-shaped teeth, with a statistically significant difference (p = 0.001). No patients were found with impacted canines and absent lateral incisors.
Conclusion: It was concluded that in patients with anomalous lateral incisors (small and peg-shaped) there is a probability to present impacted canines and this must be considered.
Association between anterior open bite and pacifier sucking habit in schoolchildren in a city of southern Brazil
Malocclusion. Prevalence. Open bite.
Objective: The objective of this study was to verify from a school-based epidemiological survey, the prevalence of anterior open bite, analyzing the influence of pacifier habit in the school.
Methods: The first step was a questionnaire for the parents, and later clinical examinations in 237 school children, 3-14 years old, in the city of Santo Expedito do Sul/RS, Brazil.
Results: The population gender distribution was 50.3% boys and 49.4% girls with a mean age of 8.63 years, and 16% had primary dentition, 50.2% mixed dentition and 33.8 % permanent dentition. There was a 22.8% prevalence of anterior open bite, obtaining a significant association between anterior open bite and the pacifier sucking habit on the three dentitions.
Conclusion: The duration and frequency of the habit were strongly associated with anterior open bite malocclusion in the deciduous and mixed dentitions.
Prevalence assessment of root dilaceration in permanent incisors
Incisor. Tooth root. Tooth abnormalities. Dental radiograph. Prevalence.
Introduction: Root dilaceration is a dental anomaly characterized by an abnormal curvature of the dental root, which can cause problems during eruption and complications in the orthodontic and endodontic treatment or extraction.
Objective: The aim of this study was to determine the prevalence of root dilaceration in permanent incisors in an oral radiology clinic in the city of João Pessoa / PB, Brazil.
Methods: The sample consisted of 548 patients who allowed assessments of their dental radiographs, a total of 3,948 examined teeth. Each tooth was examined according to the occurrence of root dilaceration, regarding type (mild, moderate or severe), root third that it was in and direction of the root. The angle formed by the root deviation in relation to the long tooth axis was obtained by means of a diagram printed on transparent acetate, placed over the radiograph.
Results: The results were analyzed with SPSS software (Statistical Package for Social Sciences) version 13.0, performing an exploratory data analysis. The prevalence of root dilaceration in the studied sample was 1.03% (41 cases), with higher incidence in males (65.8%), being the superior lateral incisor the most affected teeth (78%). The most prevalent type of root dilaceration was the mild one (73.1%), occurring more in the apical third (90.2%) and with distal direction of the root (95.1%).
Conclusion: Considering these results, it is emphasized the importance of performing a diagnostic radiographic examination prior to planning a treatment in permanent anterior teeth.
Stability evaluation of occlusal changes obtained with Fränkel?s Function Regulator-2
Angle Class II malocclusion. Orthodontic appliances. Dental models.
Objective: To analyze the stability of occlusal changes promoted by the Frankel?s Functional Regulator 2 (FR-2), in a mean period of 7.16 years post treatment.
Methods: Fifty-four pairs of models were evaluated, from 18 patients treated with FR-2. All patients had Class II, division 1 malocclusion, with initial mean age of 10.77 years and were treated with FR-2 for 18 months. The models were evaluated at the beginning of treatment (T1), at the end (T2) and after 7.16 years post treatment (T3). For occlusal evaluation, the treatment priority index (TPI) was applied on the three analyzed phases. The alterations that occurred between phases were verified with one another through paired Student?s t test, with critical value of 0.05.
Results: A statistically significant reduction of TPI was verified, from the initial to the final phase of the treatment, reflecting the efficiency of treatment performed with FR-2, specially due to improvement in molar relation, overjet and overbite. Apart from this, the Class II correction remained stable over time.
Conclusions: In this way, it is concluded that the FR-2 appliance showed to be efficient for the dental correction of Class II malocclusion, with stable occlusal results after 7.16 years post treatment.
Analysis of the cephalometric pattern of Brazilian achondroplastic adult subjects
Achondroplasia. Measures. Cephalometry. Maxillofacial abnormalities.
Objective: The aim of this study was to assess the position of the cranial base, maxilla, and mandible of Brazilian achondroplastic adult subjects through cephalometric measurements of the cranio-dento-facial complex, and to compare the results to normal patterns established in literature.
Methods: Fourteen achondroplastic adult subjects were evaluated based on their radiographic cephalometric measurements, which were obtained using the tracings proposed by Downs, Steinner, Bjork, Ricketts and McNamara. Statistical comparison of the means was performed with Student?s t test.
Results: When compared to normal patterns, the cranial base presented a smaller size in both its anterior and posterior portions, the cranial base angle was acute and there was an anterior projection of the porion; the maxilla was found to be smaller in size in both the anteroposterior and transversal directions, it was inclined anteriorly with anterior vertical excess, and retropositioned in relation to the cranial base and to the mandible; the mandible presented a normal-sized ramus, a decreased body and transverse dimension, a tendency towards vertical growth and clockwise rotation, and it was slightly protruded in relation to the cranial base and maxilla.
Conclusion: Although we observed wide individual variation in some parameters, it was possible to identify significant differences responsible for the phenotypical characteristics of achondroplastic patients.
Comparison between two methods for resin removing after bracket debonding
Orthodontics. Scanning electron microscopy. Brackets debonding. Orthodontic brackets. Tooth enamel.
Objective: The aim of this study was to assess ? using scanning electron microscopy (SEM) ? the effectiveness of two abrasive discs, one made from silicon and one from aluminum oxide, in removing adhesive remnants (AR) after debonding orthodontic brackets.
Methods: Ten randomly selected bovine teeth were used, i.e., 2 in the control group, and the other 8 divided into two groups, which had orthodontic brackets bonded to their surface with Concise Orthodontic Adhesive (3M). The following methods were employed - in one single step - to remove AR after debracketing: Group A, Optimize discs (TDV) and Group B, Onegloss discs (Shofu), used at low speed. After removing the AR with the aforementioned methods, the teeth were prepared to undergo SEM analysis, and photographs were taken of the enamel surface with 50x magnification. Six examiners evaluated the photographs applying the Zachrisson and Årtun enamel surface index (ESI) system (1979).
Results: Group A exhibited minor scratches on the enamel surface as well as some AR in some of the photographs, while Group B showed a smoother surface, little or no AR and some abrasion marks in the photographs. No statistically significant differences were found between the two methods and the control group.
Conclusions: The two abrasive discs were effective in removing the AR after bracket debonding in one single step.
Conservative compensatory Angle Class III malocclusion treatment
Angle?s Class III malocclusion. Corrective orthodontics. Extraoral traction appliances.
Introduction: Angle?s Class III malocclusion is a dental discrepancy in a sagittal view that may appear or not with an important skeletal discrepancy. Facial esthetics may be affected by this skeletal discrepancy and it is one of the most common complaints of patients who seek orthodontic treatment. Class III treatment, in adults, may be done by compensatory tooth movement, in simple cases, or through an association between orthodontics and orthognathic surgery, in more severe cases.
Objective: This article describes a non-extraction compensatory Class III treatment case, applying the Tweed-Merrifield mechanical principles with headgear (J-Hook) in the mandibular arch. This case was presented at the V Brazilian Association of Orthodontics and Dentofacial Orthopedics (ABOR) Meeting, it was evaluated by members of Brazilian Board of Orthodontics and obtained third place in the general classification.
Ethical and legal considerations on professional liability of the orthodontist
Professional practice. Legal liability. Legal system.
Introduction: After the enactment of Law 8078, of September 11, 1990, the Consumers Defense Code implied important alterations in Brazil?s legal scenario, providing a greater balance in the relationship between consumers and service providers. From this law, dental surgeons came to establish a consumer relationship with their clients.
Objective: Due to the ethical and legal issues against the dental professionals, this work makes general considerations about the nature of the dentist´s obligation in services, specifically in Orthodontics.
Conclusion: The responsibility of the professional shall be restricted to predictable risks and undertaken obligations. When the professional warns the client in a correct, clear and express manner, it will lower the chances of being later charged.
Assessment of the mechanical properties of glass ionomer cements for orthodontic cementation
Glass ionomer cements. Dental material. Cementation. Orthodontics.
Objective: To evaluate the mechanical properties of three glass ionomers cements (GICs) used for band cementation in Orthodontics.
Methods: Two conventional glass ionomers (Ketac Cem Easy mix/3M-ESPE and Meron/Voco) and one resin modified glass ionomer (Multi-cure Glass ionomer/3M-Unitek) were selected. For the compressive strength and diametral tensile strength tests, 12 specimens were made of each material. For the microhardness test 15 specimens were made of each material and for the shear bond strength tests 45 bovine permanent incisors were used mounted in a self-cure acrylic resin. Then, band segments with a welded bracket were cemented on the buccal surface of the crowns. For the mechanical tests of compressive and diametral tensile strength and shear bond strength a universal testing machine was used with a crosshead speed of 1,0 mm/min and for the Vickers microhardness analysis tests a Microdurometer was used with 200 g of load during 15 seconds. The results were submitted to statistical analysis through ANOVA complemented by Tukey?s test at a significance level of 5%.
Results: The results shown that the Multi-Cure Glass Ionomer presented higher diametral tensile strength (p < 0.01) and compressive strength greater than conventional GICs (p = 0.08). Moreover, Ketac Cem showed significant less microhardness (p < 0.01).
Conclusion: The resin-modified glass ionomer cement showed high mechanical properties, compared to the conventional glass ionomer cements, which had few differences between them.
BBO Case Report
Angle Class II, division 2 malocclusion with deep overbite
Angle Class II malocclusion. Corrective orthodontics. Overbite.
Angle Class II, division 2, malocclusion is characterized by a Class II molar relation associated with retroclined or vertical positioning of the upper incisors and in general an overbite. This clinical case was presented to the Brazilian Board of Orthodontics and Facial Orthopedics (BBO) as part of the requirements for becoming a BBO Diplomate .
Botulinum toxin for treating muscular temporomandibular disorders: A systematic review
Botulinum toxins type A. Botulinum toxins. Temporomandibular joint dysfunction syndrome. Temporomandibular joint disorders. Myofascial pain syndromes.
Objective: This study, through a systematic literature review, aims to analyze the effectiveness of Botulinum Toxin as a treatment for masticatory myofascial pain and muscles temporomandibular disorders (TMD).
Methods: Survey in research bases: MEDLINE, Cochrane, EMBASE, Pubmed, Lilacs and BBO, between the years of 1966 and April 2011, with focus in randomized or quasi-randomized controlled clinical trials, blind or double-blind.
Results: After applying the inclusion criteria, 4 articles comprised the final sample: 3 were double-blind randomized controlled clinical trials and 1 was single-blind randomized controlled clinical trial.
Conclusions: According to the literature, there is lack of evidence about the real effectiveness of botulinum toxin in the treatment of masticatory myofascial pain and muscular TMD. Thus, further randomized controlled clinical trials, with representative samples and longer follow-up time, to assess the real effectiveness of the technique are needed.