Pulp analysis of teeth submitted to different types of forces: a histological study in rats.

OBJECTIVE: The purpose of this study was to histologically evaluate pulp and dentin under induced tooth movement (ITM) with different types of forces. MATERIAL AND METHODS: The maxillary right first molars of rats were submitted to movement with continuous (CF), continuous interrupted (CIF) and intermittent (IF) forces during 5, 7 and 9 days with nickel-titanium (NiTi) closed-coil springs exerting 50cN force magnitude. The groups were histologically evaluated as for cellularity pattern, presence of dystrophic, hemodynamic alterations in the pulp as well dentin alterations. The main observed alterations were related to hemodynamic pulp characteristics, such as presence of thrombosis, vascular congestion and hemorrhages. The hemodynamic alterations were statistically evaluated by Shapiro-Wilk normality test and analysis of variance by the Kruskall-Wallis test. RESULTS: There was no significant differences observed between groups in the different types of applied forces and duration of ITM (vascular congestion, p=1.000; hemorrhage, p=0.305; thrombosis, p=1.000). CONCLUSIONS: Pulp tissue alterations resulting from ITM were limited to hemodynamic events, without progressing to irreversible degeneration, regardless of the type of force applied.

Validation of a new experimental model of extrusive luxation on maxillary molars of rats: a histological study.

BACKGROUND/AIM: The aim of this study was to test and validate a new model of extrusive luxation trauma on maxillary first molars of rats. MATERIAL AND METHODS: Forty adult male rats (Rattus norvegicus albinus, Wistar; weight = 230-250 g), 45 days old, were divided into eight groups (n = 5): control groups, in which animals were not subjected to any procedure and waited 1 day (GC1D) or 3 days (GC3D) for euthanasia, and experimental groups, in which animals were subjected to forces of 1100cN, 1300cN, or 1500cN and waited 1 or 3 days for euthanasia (GT1100/1D, GT1100/3D, GT1300/1D, GT1300/3D, GT1500/1D, GT1500/3D). In animals of the experimental groups, trauma was produced by an extrusive force in maxillary first right molars. Four-micrometer serial cuts stained with hematoxylin and eosin (HE) were made. Descriptive microscopic analysis of first upper right molar and semi-quantitative analysis (scores 1 to 4) of intensity of acute and chronic inflammation and vascular changes in the periodontal ligament and active and inactive external root resorption were conducted. The distribution of scores in the groups was compared using the Freeman-Halton extension of Fisher's exact test. The significance level was 5%. RESULTS: It was observed that vascular disorders (bleeding) on the periodontal ligament became more evident with increasing extrusive force. CONCLUSIONS: This new method was capable of generating histological changes, proving its secure application in this research area. The 1500cN force produced more damage on the periodontal ligament. CLINICAL RELEVANCE: The validation of a new experimental method can produce more reliable evidence in further research.

Prevalence of Dental Anomalies in Permanent Dentition of Brazilian Individuals with Down Syndrome.

OBJECTIVE: The aim of this study was to evaluate the incidence of dental anomalies in the permanent dentition of individuals with Down Syndrome (DS) to increase the knowledge on the dental issues in this syndrome. METHOD: One hundred and five panoramic X-rays of patients with DS (61 males and 44 females), aged 7 to 42 years were used. The data were statistically analyzed using bivariate analyses test (p <0.05). RESULTS: Dental anomalies were observed in 50.47% of the sample. More than one anomaly was observed in 9.52% of the individuals. The most frequent dental anomalies were hypodontia and microdontia (16.19%), followed by retained tooth (10.47%), taurodontism (9.52%), supernumerary teeth (5.71%), macrodontia (2.85%) and root dilaceration (0.95%). There was no statistically significant difference between genders for any of the anomalies. CONCLUSION: A high prevalence of dental anomalies was observed in individuals with DS. The results of the present study reinforce the importance of good dental care, offering a greater basis for professionals who provide dental service to these patients.

Effects of rapid maxillary expansion with six months of retention and no further orthodontic treatment / Efeitos da expansão rápida da maxila com 6 meses de contenção e sem posterior tratamento ortodôntico

Previous investigations addressing the long-term effects of rapid or slow expansion on the face and teeth involved the use of a orthodontic fixed appliance following expansion therapy. The present study evaluated changes in dentoskeletal aspects following rapid maxillary expansion (RME) and determine the stability of these changes over three years of follow up. Ten children with bilateral posterior crossbite were evaluated (experimental group). Dental casts and lateral cephalograms were evaluated prior to RME (T0) as well as three months (T1), one year (T2) and three years (T3) after RME. The measures were compared to a control group composed of 21 individuals using ANOVA and the Student's t-test (p > 0.05). Changes on the transverse plane revealed significant expansion of the upper dental arch three months after RME, stable after three years. Expansion at the cusp level was similar to that at the gingival level. No significant changes were found in the angular and linear cephalometric measures among T0, T1, T2 and T3, and in comparison to the control group (p > 0.05). We concluded that early RME produces stable transverse increases in the upper arch after three years without significantly altering sagittal and vertical dentoskeletal relationships, and neither inclined teeth.

A expansão rápida ou lenta da maxila seguida do uso de aparelhos ortodônticos fixos altera a face e os dentes. Este estudo avaliou as mudanças dentoesqueléticas após a expansão rápida da maxila (ERM) e determinou a estabilidade dessas mudanças em três anos de acompanhamento. Dez crianças com mordida cruzada posterior bilateral foram avaliadas (grupo experimental). Modelos de estudo e telerradiografias laterais foram avaliadas antes da ERM (T0), assim como três meses (T1), um ano (T2) e três anos (T3) após a ERM. As medidas foram comparadas às de um grupo controle composto de 21 pacientes por meio do teste ANOVA e teste t Student (p > 0,05). As mudanças no plano transversal revelaram uma expansão significante no arco superior três meses após a ERM, que se manteve estável após três anos. A expansão ao nível das cúspides foi similar à do nível gengival. Mas nenhuma diferença significante foi encontrada estre as medidas cefalométricas angulares e lineares ao longo dos períodos T0, T1, T2, e T3 e nem quando se comparou essas medidas às do grupo controle (p > 0,05). Conclui-se que A ERM precoce produz aumentos transversais estáveis no arco superior sem alterar significantemente as relações sagitais e verticais dentoesqueléticas e nem inclinar dentes.

Hábitos bucais deletérios em pessoas com deficiência / Oral habits in people with disabilities

Pessoas com deficiências apresentam alto índice de más oclusões, o que pode estar relacionado ao crescimento e desenvolvimento anormais, além da alta incidência de hábitos bucais deletérios (HBD). Os dados sobre a distribuição dos HBD nos diferentes tipos de síndrome ou deficiência são escassos, portanto, o objetivo desse trabalho foi avaliar a prevalência dos HBD em pacientes com deficiências. A amostra foi composta por 100 pacientes, sendo 56 do sexo masculino (56%) e 44 do sexo feminino (44%), com idade média de 33,5 anos. Em relação ao tipo de deficiência, 47 pacientes apresentavam Retardo Mental (RM), 35 Paralisia Cerebral (PC) e 18 Síndrome de Down (SD). Constatou-se que 24 pacientes (24%) não apresentavam nenhum HBD, sendo 19 com RM, 3 com SD e 2 com PC. Quanto ao número de HBD, 35 pacientes (35%) foram diagnosticados com 1 HBD, 23 (23%) com 2 HBD e 18 (18%) com 3 ou mais HBD. Na PC, a respiração bucal foi o HBD mais prevalente (54,3%), seguido da interposição lingual (42,9%). A respiração bucal também foi o HBD mais frequente nos pacientes com RM (34%), já nos pacientes com SD, chama atenção o grande número de indivíduos que apresentaram interposição lingual (61,1%) e respiração bucal (50%). O alto índice de HBD comprova a necessidade de maior atenção dos profissionais para o desenvolvimento de procedimentos interceptores e corretivos específicos para os pacientes com deficiência. Além disso, os responsáveis devem ser orientados sobre as consequências dos hábitos mais prevalentes (AU).

People with disabilities have a high rate of malocclusion, which may be related to abnormal growth and development, and the high incidence of oral habits (OH). Data on the distribution of OH in the different types of syndrome or disability are limited, so the aim of this study was to evaluate the prevalence of OH in patients with disabilities. The sample consisted in 100 patients, 56 male (56%) and 44 female (44%), mean age of 33.5 years old. Regarding the type of disability, 47 patients had Mental Retardation (MR), 35 Cerebral Palsy (CP) and 18 Down Syndrome (DS). It was found 24 patients (24%) did not have any HBD, 19 with RM, 3 with SD, and 2 PC. As the number of OH, 35 patients (35%) were diagnosed with 1 OH, 23 (23%) 2 OH, and 18 (18%) had 3 OH or more. In PC, mouth breathing was the most prevalent OH (54.3%), followed by tongue thrusting (42.9%). Mouth breathing was also the most frequent in patients with MR (34%), while in patients with SD, the large number of individuals had tongue thrusting (61.1%) and mouth breathing (50%). The high level of OH proves the need for greater attention of professionals for the development of specific interceptors and corrective procedures for patients with disabilities. In addition, those responsible must be informed about the consequences of the most prevalent habits (AU).

Prevalence of malocclusion in people with disabilities / Prevalência de más oclusões em pessoas com deficiência

Objetivo: Avaliar a prevalência de má oclusão em pacientes com deficiências. Materiais e Métodos: A amostra foi composta por 98 pacientes com o diagnóstico prévio da deficiência. Os pacientes foram distribuídos em três grupos: deficiência intelectual (DI), paralisia cerebral (PC) e síndrome de Down (SD). Eles foram avaliados de acordo com a classificação de Angle para má oclusão, presença ou ausência de mordida cruzada posterior, mordida cruzada anterior e mordida aberta anterior. A análise estatística dos dados foi realizada utilizando o teste de Kruskal Wallis com nível de significância de 5%. Resultados: A Classe II foi mais frequente nos três grupos (PC 45,45%, DI 40,43% and SD 50,00%); a mordida cruzada anterior e posterior foram mais prevalentes na SD (p < 0,0001). A mordida aberta anterior foi mais prevalente na PC (p < 0,0001). Conclusão: Pacientes com deficiência apresentam altas taxas de má oclusão e compreender esta condição é essencial para estabelecer o tratamento mais adequado.

Objective: To evaluate the prevalence of malocclusion in patients with disabilities. Material and Methods: The sample consisted in 98 patients of who had a previous diagnosis of disability. Patientes were divided into three groups: Intelectual Disabilities (ID), Cerebral Palsy (CP) and Down Syndrome (DS). They were evaluated according to Angle malocclusion classification, presence or absence of posterior crossbite, anterior crossbite and anterior open bite. Statistical analysis of the data was performed using the Kruskal Wallis test at 5% significance level. Results: Class II malocclusion was more frequent in the three groups (CP 45.45%, ID 40.43% and DS 50.00%); the anterior and the posterior crossbite were more prevalent in DS (p < 0.0001). The anterior open bite was more prevalent in CP (p < 0.0001). Conclusion: Patients with disabilities have high rate of malocclusion and understanding this condition is essential to establish appropriate treatment

Effect of alendronate sodium on tooth movement in ovariectomized rats.

OBJECTIVES: The aim of the present study was to evaluate the effect of two different dosages of alendronate on induced orthodontic movement in an experimental model involving rats with osteoporosis following ovariectomy. DESIGN: Female Wistar rats (Rattus norvegicus) eight weeks of age were divided into four groups (n=12/group): ovariectomized (OVX group); ovariectomized and treated with alendronate sodium at 1mg/kg (Group OVX+ALN1); ovariectomized and treated with alendronate sodium at 2mg/kg (Group OVX+ALN2); and sham operated (control). Three months after ovariectomy, the maxillary right first molar was submitted to movement for five and seven days. After the death of the animals, the maxilla were removed and processed for microscopic evaluation. The maxillary left first molar (without movement) was used for comparison purposes in all groups. The samples were processed for the quantification of alveolar bone and tooth movement. RESULTS: Intragroup comparisons showed significant movement after five and seven days (p<0.05) for all groups. Comparison among groups revealed greater tooth movement in the OVX group (p<0.05), on day 7. CONCLUSIONS: Both alendronate sodium doses similarly decreased tooth movement in ovariectomized rats (p>0.05). Movement in ovariectomized+alendronate groups were also smaller than non-ovariectomized rats, however without statistical difference.

Dental development of children and adolescents with cleft lip and palate

Aim: To evaluate the dental development of Brazilian children and adolescents with cleft lip and palate. Methods: The sample consisted of 107 panoramic radiographs of children and adolescents with cleft lip and/or palate (cleft group) and 107 panoramic radiographs of children and adolescents without cleft lip and/or palate (control group), with chronological ages ranging from 6 to 15 years, matched in gender and chronological age within 60 days. Radiographs were digitized and masked and dental age was assessed using the method described by Demirjian et al. (1973). Three trained examiners conducted the assessments. Each examiner evaluated the radiographs three times. Data were statistically analyzed using non-parametric tests and univariate linear regression (p<0.05). Results: The dental age was overestimated in relation to the chronological age in both groups (p<0.0001). Compared to the control group, there was a delay in the dental age in the cleft group of 0.17 years (2.1 months). However, no statistically significant difference in the dental age between the cleft and the control group was found even when considering the different cleft types (p=0.152). Conclusions: There was no statistically significant difference in the dental age between the cleft and the control groups. The evaluation of dental development in individuals with cleft lip and palate should be approached in the same way as in individuals without clefts, with a focus on the individualization of diagnosis and treatment planning.

Analysis of mesiodistal angulations of preadjusted brackets.

Manufacturers offer various prescriptions of preadjusted brackets for use in the "straight-wire" orthodontic technique. However, the need to incorporate bends in the rectangular wires during orthodontic finishing has led to concerns regarding the type of prescription chosen and the credibility of information provided by the manufacturer. The aim of this study was to compare the slot angulations of Roth prescription preadjusted metallic brackets for the maxillary left central incisor and maxillary left canine. For each tooth type, 10 brackets of three commercial brands (GAC, Forestadent and Morelli) were selected. Two individual metal matrices for brackets and tooth positioning were made for each group of teeth. Captured images were obtained by standardized ortho-radial photography with a digital camera. Images were exported and analyzed with the Image J software package. One-way ANOVA and Tukey statistical analyses were performed at the 5% significance level. For brackets of the maxillary left central incisor, differences in mean angulation were observed between the Morelli and GAC groups (p < 0.01) and between the Forestadent and GAC groups (p < 0.01). For brackets of the maxillary left canine, differences in mean angulation were found between the Morelli and GAC groups (p < 0.01) and between the Morelli and Forestadent groups (p < 0.05). In conclusion, despite their same prescription name, the different brands exhibited significantly different angulation measurements.

Resorption of roots of different dimension induced by different types of forces.

Root resorption is a variable to be considered in induced tooth movement (ITM). It is related to root morphology and alveolar bone crest, and also to the types of forces exerted by mechanotherapy. This histometric study evaluated the predominance of root resorption among roots of different dimensions, following ITM with different types of forces and at different time intervals. The study was conducted on 54 rats divided into three groups, according to the type of force: continuous (CF), continuous interrupted (CIF) and intermittent (IF), at periods of 5, 7 and 9 days. The percentage of resorption between mesiobuccal roots of larger dimension and intermediate roots of smaller dimension was assessed. The evaluations were performed on the AxioVision software, and the non-parametric analysis of variance for repeated measures in independent groups was further applied, consisting of a scheme of two factors, and complemented by the Dunn test at a significance level of 5%. The intermediate roots presented a higher percentage of resorption, which was gradual at the periods evaluated for the three types of forces, but mainly for CF. Comparing the intermediate roots with the mesiobuccal roots, there was a statistically significant difference (p<0.05) in the CF group at day 7 and day 9, and in the FI group, at day 9. The intragroup analysis evidenced a statistically significant difference (p<0.05) between the 5th and the 9th day for the intermediate root in the CF group. The intergroup analysis did not reveal any statistically significant difference (p>0.05) in individually analyzed roots.

Microscopic evaluation of induced tooth movement after subluxation trauma: an experimental study in rats.

OBJECTIVE: The objective of this study was to assess the histological alterations that occurred in the periodontal area of rat molars submitted to induced tooth movement (ITM) right after an intentional trauma (subluxation). METHODS: Forty adult male Wistar rats (Rattus norvegicus albinus) were selected. The animals were divided into eight groups (n=5), according to the combination of variables: Group 1--control (neither trauma nor ITM); Group 2--ITM; Groups 3, 4, 5 and 6--dentoalveolar trauma groups corresponding, respectively, to 1, 3, 8 and 10 days after trauma; Groups 7 and 8 - the animals' molars were subjected to a 900 cN impact and, one and three days after the trauma event, tooth movement was induced. The rats' maxillary first molars were mesially moved during seven days with a closed coil (50 cN). After the experimental period of each group, the animals were sacrificed by anesthetic overdose and the right maxillas were removed and processed for histological analysis under light microscopy. RESULTS: In the animals of group 3, 4, 5 and 6, the histological alterations were not very significant. Consequently, the effect of induced tooth movement right after a subluxation event (groups 7 and 8) was very similar to those described for Group 2. CONCLUSIONS: There was no difference in the quality of periodontal repair when ITM was applied to teeth that had suffered a subluxation trauma.

Microscopic evaluation of induced tooth movement after subluxation trauma: an experimental study in rats

OBJECTIVE: The objective of this study was to assess the histological alterations that occurred in the periodontal area of rat molars submitted to induced tooth movement (ITM) right after an intentional trauma (subluxation). METHODS: Forty adult male Wistar rats (Rattus norvegicus albinus) were selected. The animals were divided into eight groups (n = 5), according to the combination of variables: Group 1 - control (neither trauma nor ITM); Group 2 - ITM; Groups 3, 4, 5 and 6 - dentoalveolar trauma groups corresponding, respectively, to 1, 3, 8 and 10 days after trauma; Groups 7 and 8 - the animals' molars were subjected to a 900 cN impact and, one and three days after the trauma event, tooth movement was induced. The rats' maxillary first molars were mesially moved during seven days with a closed coil (50 cN). After the experimental period of each group, the animals were sacrificed by anesthetic overdose and the right maxillas were removed and processed for histological analysis under light microscopy. RESULTS: In the animals of group 3, 4, 5 and 6, the histological alterations were not very significant. Consequently, the effect of induced tooth movement right after a subluxation event (groups 7 and 8) was very similar to those described for Group 2. CONCLUSION: There was no difference in the quality of periodontal repair when ITM was applied to teeth that had suffered a subluxation trauma. .

OBJETIVO: avaliar as alterações histológicas ocorridas na área periodontal de molares de ratos submetidos à movimentação dentária induzida (MDI), logo após um trauma intencional (subluxação). MÉTODOS: quarenta ratos Wistar machos adultos (Rattus norvegicus albinus) foram selecionados. Os animais foram divididos em oito grupos (n = 5), de acordo com a combinação das variáveis: Grupo 1 - controle (sem trauma e sem MDI); Grupo 2 - MDI; Grupos 3, 4, 5 e 6 - grupos de trauma dentoalveolar correspondendo, respectivamente, para 1, 3, 8 e 10 dias após o trauma; Grupos 7 e 8 - os molares murinos foram submetidos a um impacto de 900cN e, de um e três dias após o evento trauma, o movimento do dente foi induzido. Os primeiros molares superiores dos animais foram movidos mesialmente durante sete dias, com uma mola fechada (50cN). Após período experimental de cada grupo, os animais foram sacrificados por overdose anestésica e as maxilas direitas foram removidas e processadas para análise histológica qualitativa. RESULTADOS: nos animais dos grupos 3, 4, 5 e 6, as alterações histológicas não foram muito significativas. Consequentemente, o efeito do movimento dentário induzido logo após um evento de subluxação (grupos 7 e 8) foi muito semelhante ao descrito para o grupo 2. CONCLUSÃO: não houve diferença na qualidade do reparo periodontal quando a MDI foi aplicada aos dentes que sofreram um trauma de subluxação. .

Induction of ankylosis in the incisor for orthodontic tooth movement in rats.

BACKGROUND/AIM: The present research evaluated the induction of ankylosis and the eruption rate in rat incisors, with the aim of achieving stable anchorage for orthodontic tooth movement (OTM) of the molars. MATERIAL AND METHODS: Fifteen male Wistar rats were used. In the Experimental group, the right superior incisor of each animal was extracted, denuded of the PDL and the dental papilla, and reimplanted. The Control group was the left superior incisors. The eruption rate was measured at 7, 10, 12, 14, and 16 days after replantation. NiTi closed springs with a 50cN release force were installed for additional 9 days, and the eruption rate was determined. Then, the rats were sacrificed, and ankylosis was examined by microscopic analysis. Differences with P < 0.01 were defined as statistically significant. RESULTS: The eruption rates were 0 and 0.39 mm day(-1) in the Experimental group and Control group, respectively. All incisors of the Experimental group showed ankylosis according to histological analysis. CONCLUSIONS: The methodology used to induce ankylosis in this study was effective for anchoring the incisors during the OTM of rat molars, eliminating the undesirable effects consequent to continuous eruption.

Importance of periodontal ligament thickness

This study evaluated whether periodontal ligament (PL) thickness varied with root size and examined the possible influence of this variation on orthodontic mechanics. Measurements were taken of the maxillary left first molar in 54 male Wistar rats. Mean mesial and distal PL thicknesses were compared between the intermediate buccal and mesiobuccal roots using paired Student's t-tests with a 5% significance level. Mean values differed significantly between roots (p < 2.2 × 10-16). PL thickness in rats is directly proportional to root dimensions.

Importance of periodontal ligament thickness.

This study evaluated whether periodontal ligament (PL) thickness varied with root size and examined the possible influence of this variation on orthodontic mechanics. Measurements were taken of the maxillary left first molar in 54 male Wistar rats. Mean mesial and distal PL thicknesses were compared between the intermediate buccal and mesiobuccal roots using paired Student's t-tests with a 5% significance level. Mean values differed significantly between roots (p < 2.2 × 10(-16)). PL thickness in rats is directly proportional to root dimensions.

Extrações seriadas: protocolos e implicações clínicas / Serial extractions: protocols and clinical implications

A Ortodontia é uma especialidade da Odontologia que visa, entre seus diversos objetivos, proporcionar uma arcada dentária alinhada, estável e funcional. A discrepância dentoalveolar negativa em indivíduos na fase de dentição mista apresenta alta prevalência e requer a utilização de métodos de tratamento que proporcionem a obtenção de espaço. As extrações seriadas constituem uma solução adequada, mas frequentemente questionada quanto às indicações, contraindicações e sequência apropriada. Assim, o propósito deste artigo é apresentar uma discussão, embasada na literatura pertinente, dos principais fatores envolvidos com esse procedimento e ilustrar esta terapia por meio de um caso clínico.

Histomorphometric evaluation of periodontal compression and tension sides during orthodontic tooth movement in rats

OBJECTIVE: The purpose of this study was to evaluate the thickness of the periodontal ligament of rat molars during orthodontic tooth movement (OTM). METHODS: Thirty Wistar rats were divided into three groups of 10 animals each: GI, GII and GIII and the mice were euthanized at 7, 14 and 21 days, respectively. Experimental subjects were compared to their respective controls by the Mann-Whitney test. Comparison of values between compression and tension sides were performed during the same and different time periods through Analysis of Variance (ANOVA), Kruskal-Wallis test and, subsequently, Tukey's test. RESULTS: Groups GI and GII showed decreased PDL size in the apical regions of the mesiobuccal root and in the cervical region of the distobuccal root. There was also an increased PDL in the cervical regions of the mesiobuccal root, apical region of the distobuccal root and middle region of both roots. CONCLUSION: The reduction and increase in PDL size were seen in the same root, which characterizes tooth inclination. The apical, middle and cervical regions were compared with one another in each time period and at three times: 7, 14 and 21 days. They were also compared in each region, confirming a tipping movement in GI and GII and a gradual decreased intensity between GI to GII, reaching normal dimension in GIII.

Movimentação dentária e aplicabilidade na clínica ortodôntica / Tooth movement and its applicability in Orthodontic Clinics

A Ortodontia apresenta como um de seus pilares de sustentação as reações biológicas provenientes da indução mecânica. Desde seu início, vários estudos foram realizados para esclarecer os eventos biológicos decorrentes da movimentação dentária sob indução mecânica. Entretanto, mesmo sabendo-se que entre os procedimentos mecânicos e os fenômenos biológicos que acontecem no cotidiano ortodôntico não deve ocorrer disparidade, frequentemente observa-se uma preponderância para a busca do tipo de aparelhagem e o emprego de forças controladas, principalmente pelos fios. Esses aspectos deixam transparecer, principalmente para o profissional menos experiente, que somente o controle mecânico rege a movimentação dentária. Um exemplo que enfatiza exclusivamente o procedimento mecânico nos cursos de Ortodontia é o typodont. Convém salientar que essa metodologia de ensino é válida para simular a movimentação dentária no aspecto técnico-mecânico, porém, o conhecimento biológico da movimentação deve ter o mesmo nível de importância e não pode haver dicotomia; caso contrário, o resultado da movimentação ortodôntica pode causar prejuízos nas estruturas radiculares, óssea e periodontais, bem como comprometer as diversas estruturas em longo prazo.

Interceptive approach to treatment of impacted maxillary canines.

Impaction of maxillary canines can be prevented by early intervention in the mixed dentition phase after the correct diagnosis of malocclusion, reducing the complexity of the treatment. This article reports the case of a 10-year-old patient who possessed impacted maxillary canines and, after early extraction of primary canines, had reestablished favorable permanent successors' eruption axis. This 5-year radiographic follow-up study with panoramic radiography shows that this can be used in practice and that an effective control strategy ensures the accuracy in the inclination of the impacted canines. Treatment success is related to early diagnosis and strategic interceptive treatment choice.