Manifestation of molar-incisor hypomineralisation in twins: clinical case reports

Molar-incisor hypomineralisation is a qualitative defect of dental tissue of systemic origin affecting one or more permanent first molars and sometimes the permanent incisors as well. There are still no conclusive data on the aetiology of this hypomineralisation, however, systemic factors such as respiratory diseases and prenatal and perinatal complications are regarded as possible causes. The objective is to present three clinical cases of twins, one Monozygotic and two Dizygotic Twins with molar-incisor hypomineralisation, showing evidence of its manifestation as well as clinical the characteristics and aetiological factors involved. The clinical findings involving twins suggest that ameloblasts are specifically affected in their developmental phase, which includes a number of factors. Although prenatal and perinatal complications are not decisive in the development of molar-incisor hypomineralization, it is suggested a possible genetic susceptibility to the disease. Prospective observational studies using a population sample containing data on the last three months of gestation to the eruption of permanent teeth are needed to confirm the causeeffect relationships.

Schwartz-Jampel Syndrome: a paediatric dentistry approach

Schwartz-Jampel syndrome (SJS) is a rare recessive disorder characterized mainly by myotonia. As the clinical signs and symptoms are manifested in the oromaxillofacial region, paediatric dentists may be first choice of parents that seek information and assistance to their children. A female patient diagnosed with SJS was brought to our clinic for dental treatment with main complain of difficulty on oral hygiene and mastication due to tooth crowding. The treatment included preventive measures, extraction of a supernumerary tooth and the maxillary primary second molars. Furthermore, the patient was referred to orthodontic treatment for correction of tooth crowding. When dealing with children with confirmed diagnosis of SSJ, paediatric dentists should be understand the need of planning the dental treatment considering the characteristics and possible complications associated with the syndrome in order to reduce the risks to patients, especially when surgical procedures are necessary.

Hipomineralización incisivo Y molar: diagnóstico diferencial

Hypomineralized first molar often in combination with hypomineralized incisors (MIH - molar incisor hypomineralization) is a common finding in everyday practice. In this condition, hypomineralized dental enamel is fragile and soft, and it can break easily leading to an exposed dentin, and causing dental sensitivity and progression of caries lesions. The prevalence of MIH range from 3.6 to 25% in North of Europe that consider this condition a public health problem. No conclusive information was reported about the etiologic factors of MIH, however, systemic causes seem to be of importance. Several aetiological factors are mentioned as the cause of this condition and they are frequently associated with complications during pregnancy and childhood diseases during the first three years of life. MIH is frequently misinterpreted as fluorosis, hypoplasia or amelogénesis imperfect, however, this condition presents defined clinical aspects that can distinct it from the other defects.

Aparelho extrabucal como recurso auxiliar para alinhamento e nivelamento no tratamento orto cirúrgico de má oclusão classe III esquelética

When well indicated, the orthodontic surgical approach is the ideal treatment mean for Skeletal Class III adult patients. To improve facial esthetic results from orthognatic surgery, the leveling and alignment of maxillary dental arch must be achieved with minimal inclination and projection or even retro-inclination of anterior upper teeth. During a pre-surgical phase of 12 months, headgear bilateral force of 150 g/F was applied to the upper molars of a 22 years old male compliant patient with Class III skeletal malocclusion, to provide an upper teeth control of mesial tipping and projection during alignment and leveling. The ideal occlusal parameters required for surgical procedure were achieved without dental extractions permitting a total treatment period of 37 months. The outcomes remained stable over 3 years follow up after the removal of the appliance. The results indicate that, although headgear use depends greatly on patient compliance, when well indicated it is an interesting alternativetopromote dentaldecompensationon pre-surgical period, in order to allow surgical correction of skeletal Class III malocclusion.

Estudo em telerradiografia em norma de 45º no tratamento da classe II com aparelho de Herbst

The aim of this retrospective study was to evaluate mandibular and maxillary changes induced by the use of Herbst applianceand by natural growth through oblique cephalometric radiographs in children with Class II division 1 malocclusion with mandibular retrusion. A sample of 49 individuals with age ranging from 8 to 10 years old (before growth peak) with Class II division 1, were into two groups: Herbst treated group (n=24) and control group (n=25). Both groups were paired for gender and chronological age. Statistical analysis was performed through Student’s t test. The Herbst appliance promoted the Class II correction in a 7 months period by mesialization of lower permanent first molars and distalization of upper permanent first molars. The Herbst appliance had no influence over the mandibular structure or the mandibular length. It was concluded that early treatment with Herbst appliance corrected the Class II malocclusion by means of dentoalveolar changes.

Alterações dentoesqueléticas verticais e horizontais induzidas pelo ativador elástico Aberto de Klammt

The aim of this study was to evaluate the vertical and horizontal dentoskeletal changes induced by the Klammt Open Elastic Activator in the treatment of the Class II Division 1 malocclusion. The sample of 34 children was divided into two groups of 17 subjects each (ten girls, seven boys), matched by age and gender and with an initial mean age of 8.5 years. The data was analyzed using a Student's t-test for intragroup and intergroup comparison. The results showed that the appliance promoted dentoalveolar restriction of the maxilar growth within normal anteroposterior and vertical growth of the maxillary apical base; increment in the vertical displacement the mandibular symphysis associated with normal horizontal growth of the mandible; palatal tipping of the upper incisors; restriction of the anterior migration of the upper molars; greater eruption pattern and normal anterior displacement of the lower incisors and molars. It was concluded that Klammt appliance induce changes that are predominantly horizontal dentoalveolar in upper arch and vertical dentoalveolar in lower arch and vertical skeletal changes in the mandible.

Alterações dimensionais em pacientes submetidos à expansão rápida da maxila com aparelho do tipo Haas

The maxillary atresia is a alteration in the transverse dimension that can result in a unilateral or bilateral crossbite. For correction of atresia of the upper dental arch appliances with the intent to expand the arch of orthopedic or orthodontic manner are used, obtaining across-compatibility between the dental arches. The purpose of this study was to evaluate the dimensional changes of the maxillary in patients in the mixed dentition with atresia in the upper dental arch, using occlusal radiographs taken before, after rapid maxillary expansion and after removal of the appliance. Methods: the sample consisted of 35 patients who used the appliance type conventional Haas, in the mixed dentition, according to the standard protocol for installation, activation, containment and removal of the appliances rapid maxillary expansion. Results: the results confirm that the suture opening occurs in greater quantities in the anterior (4.3 mm) than posterior to (3.74 mm), representing a triangular opening of 7 degrees on average with the posterior opening 87% of the quantity of anterior opening. The molars region expanded about 5 mm, and the base bone 3.7 mm, representing a 74% bone expansion of the expansion teeth.

Avaliação das alterações dentárias e esqueléticas induzidas pelo uso do aparelho de Herbst no tratamento da classe II na dentadura mista: Revisão sistemática

Objective: evaluate the immediate dental and skeletal changes induced by the Herbst appliance on early treatment of Angle´s Class II malocclusion. Material and Method: several electronic databases such as Scopus, Pub Med, Medline, Cochrane Library, Lilacs and Scielo were searched. The abstracts that fullfilled the selection criteria were selected and those that did not provide enough information about these criteria were selected but the final decision of including them or not on the research, was taken after the complete reading of the article. The selection criteria were: clinical studies with Class II individuals, both male and female, with initial age of 7 to 10 years, treated with the Herbst appliance that analysed the dental and/or skeletal changes evaluated on lateral cephalometric radiographs; researches where the treatment performed did not involve extractions or surgical interventions; studies that included patients without syndromes or health concerns and articles published in English or Portuguese. Results and Conclusions: five articles were selected. The articles showed that significant changes happened in the mandibular sagittal lenght, on facial convexity angle, on maxillo-mandibular relationship, on retroclination of the upper incisors and on distal movement of the upper molars, on proclination of the lower incisors and on extrusion of the lower molars. The appliance exerted a limited effect on the anterior relocation of the maxillary complex and on facial heights. However, more studies about the performance of the Herbst appliance on early treatment of Class II are needed.

Avaliação das dimensões e relacionamento dos arcos dentários após tratamento com Bionator de Balters

The deficiency of data in the literature took us to evaluate the Bionator of Balters appliance in the alterations of the dimensions and the relationship of the dental archs in children with malocclusion Class II, division 1 of Angle. The experimental group was constituted by 36 pairs cast Caucasians patients, aged between 7 years and 10 months - 11 years and 8 months, being 10 females and 8 males. The Levene´s test showed statistical evidences of likeness among the groups. Statistical analysis was preceded and showed significant alterations (p < 0,005) in the variable indicatives of maxillary first molars' distance, overjet, upper arch total length, upper arch anterior length, right molar relationship, left molar relationship, right canine relationship and left canine relationship. On the other hand, there wasn't significant alteration related to the lower arch and maxillary intercanines distance. The Balters' Bionator appliance had a favorable effect in the improvement of the correction of the malocclusion in Class II (foremost in molars and canines relationship) and transversal increase of the upper arch, mainly in the posterior area of arch.

Dimensões do corredor bucal e sua relação com a distância inter pré-molar e intercomissural

The objective of the study was to analyze the size of buccal corridor during the smile of individuals from 10 to 19 years of age and to determine whether there is a relationship among buccal corridor, inter premolar distance, inter commissure width. Standard digital frontal photographs in posed broad smiles and dental casts were taken of a sample of 150 individuals divided into 5 age groups of 30 individuals: 10-11 years old (G1), 12-13 years old (G2), 14-15 years old (G3), 16-17 years old (G4), 18-19 years old (G5). Distances among the cusps of superior first premolars and buccal corridors were measured for subsequent comparisons using the Image Tool 3.0 program. Data was analyzed using Anova. The SNK test and Tamhane test were applied. The mean values of the buccal corridor ranged from 4.00-to 10.69 mm on the right side and from 4.06 to 11.43 mm on the left side. In percentage related with intercomissure width each side of the buccal corridor ranged from 7.46 to 16.47% on the right side and from 7.58% to 17.61% on the left side. Buccal corridors were different between genders and increased with age. Males have bigger buccal corridors than females, but there is no difference between gender when calculated as a percentage related with the inter commissure width. The inter premolar width is significantly correlated with inter commissure widths of female individuals 14-15 years old and 18-19 years old, and with the right linear buccal corridor of males and females aged 14-15 years old.

Modificação de forma e dimensões dos arcos superior e inferior obtidas em modelos de estudo após expansão rápida da maxila com o aparelho hyrax

The aim of an orthodontic treatment is the achievement of a balanced, esthetic and, most of all, stable, intra and inter arches relationship. A common problem observed in occlusion is posterior crossbite and atresic maxilla. This problem may be treated by slow expansion, rapid expansion or surgically assisted expansion. For the present study cast models of 14 children between 7 and 11 years old were evaluated. There were 7 male and 7 female subjects that presented posterior crossbite and needed rapid maxillary expansion. The Hyrax appliance performed the therapy for correction of this transversal alteration, which is a common possibility in the treatment of this malocclusion. It was observed that the distance between the upper first molars and upper cuspids increased significantly; the length of the upper arch decreased and its perimeter increased significantly. At the lower arch there were no dimensional changes.

Descrição do aparelho VABB (Vertically Activated Bite Block) para o tratamento da mordida aberta anterior

Nowadays, the correction of skeletal vertical dysplasia is considered a great challenge in Orthodontics. The skeletal open bite treatment presents limitations related to vertical growth pattern, the extension of open bite and especially the stability, which is very questioned. The treatment of skeletal open bite is mostly realized by the inhibition of vertical alveolar posterior development (relative intrusion) or absolute intrusion of posterior teeth, through vertical forces, generated by the action of masticatory muscles. The purpose of this article is to present a new appliance for the treatment of skeletal open bite, the VABB (Vertically Activated Bite Block) or modified Bite Block, whose action mechanism is to limit the vertical development of the molars, by the action of facial muscles and two bilateral expansion screws that provide a counterclockwise rotation of the mandible. It will also be presented a clinical case and the technical steps for the construction of this appliance.

Ertty System®: distalização segmentar

Introduction: Ertty System® is an intraoral system of biomechanical forces to move teeth anteroposteriorly. The application of forces on this system results in the distalization of the molar and all lateral segment in the side to be distalized, including premolars and canine, resulting in alveolar bone remodeling. This system is indicated to correct uni- or bilateral maxillary dental Class II malocclusion in permanent dentition both in children and adults. It is contraindicated in case of skeletal asymmetries, protrusion of maxillary and mandibular teeth, skeletal Class II and Class II subdivision malocclusions with mandibular midline deviation. This study describes Ertty System® and presents two clinical cases treated using this system. The two female patients presented with Class II malocclusion subdivision and maxillary midline deviation. Results: It was achieved correct alignment and leveling, Class I dental relation and correction of upper midline. Conclusion: The success and stability of results confirmed diagnosis and treatment adequacy.

Otimização do tracionamento de canino impactado pela técnica do arco segmentado: relato de caso clinico

Upper canines impaction are considered the second most frequent and are associated to important esthetics and functional limitations. Among the treatment strategies described in the literature the most commonly used are the extraction of the primary canines and the surgical exposure followed by orthodontic traction, that requires an adequate interdisciplinary approach. The aim of this case report is to draw the attention of the clinician to the possibility of adapting the segmented arch technique to manage a canine impaction clinical case.

Resistência ao cisalhamento de bráquetes fotopolimerizados com arco de plasma, LED e luz halógena utilizando diferentes tempos

This study evaluated in vitro the shear bond strength of brackets bonded with xenon plasma arc light, light-emitting diode (LED) and conventional halogen light using different curing times. Brackets were bonded to the buccal surface of 60 human maxillary premolars allocated to five groups. In groups 1 and 2, the resin was cured with the plasma arc for three and six seconds (s), respectively; in groups 3 and 4, the LED was used for five and ten s, respectively; and in group 5, the halogen light was used for 40 s. The specimens were stored in water for 24 hours and subjected to a shear force until bracket failure. The debonding pattern was classified according to the adhesive remnant index (ARI). The results were assessed by Anova and the SNK post-hoc test. No differences were detected among groups 2, 4 and 5, which showed higher averages than groups 1 and 3, which were not different between themselves. The ARI scores showed no differences among the three types of light sources in all times tested. Plasma arc and LED lights can be used with shorter curing times, within certain limits, than conventional halogen light for bonding orthodontic brackets, without decreasing bond strength.