Dentoalveolar effects of skeletally anchored extrusion arch in anterior open bite patients: A prospective clinical trial.

OBJECTIVE: The purpose of this prospective clinical trial was to explore the dental and soft tissue changes accompanying the use of skeletally anchored nickel-titanium (NiTi) extrusion arch in the correction of anterior open bite (AOB). MATERIAL AND METHODS: Twenty female patients with a mean age of 16.5 ± 1.5 years and a mean dentoalveolar AOB of 2.38±0.7 mm participated in this study. All patients were treated with an maxillary 0.017×0.025-in NiTi extrusion arch, with the aid of miniscrews inserted between the maxillary second premolars and first molars bilaterally, to act as indirect anchorage. Three-dimensional digital models and lateral cephalometric radiographs were taken just before the insertion of the extrusion arch (T0) and after 10 months (T1). Paired-sample t-tests were used in analyzing the data, to evaluate the changes after treatment (T1-T0). A significance level of p < 0.05 was used. RESULTS: AOB was successfully closed in all patients, with a 4.35 ± 0.61 mm increase in the overbite. Maxillary incisors significantly extruded (2.52 ± 1.02 mm) and significantly reclined (5.78 ± 0.77°), with a resultant decrease in the overjet of 1.58 ± 0.5mm. A significant intrusion of maxillary first molars with no change in their inclination was observed. The upper lip showed a significant retraction tendency to the E-plane, and a significant increase in the nasolabial angle was observed. CONCLUSION: The skeletally anchored NiTi extrusion arch was an effective technique in treating AOB, with no adverse effects on the molars.

Dentoalveolar effects of skeletally anchored extrusion arch in anterior open bite patients: A prospective clinical trial

ABSTRACT Objective: The purpose of this prospective clinical trial was to explore the dental and soft tissue changes accompanying the use of skeletally anchored nickel-titanium (NiTi) extrusion arch in the correction of anterior open bite (AOB). Material and Methods: Twenty female patients with a mean age of 16.5 ± 1.5 years and a mean dentoalveolar AOB of 2.38±0.7 mm participated in this study. All patients were treated with an maxillary 0.017×0.025-in NiTi extrusion arch, with the aid of miniscrews inserted between the maxillary second premolars and first molars bilaterally, to act as indirect anchorage. Three-dimensional digital models and lateral cephalometric radiographs were taken just before the insertion of the extrusion arch (T0) and after 10 months (T1). Paired-sample t-tests were used in analyzing the data, to evaluate the changes after treatment (T1-T0). A significance level of p < 0.05 was used. Results: AOB was successfully closed in all patients, with a 4.35 ± 0.61 mm increase in the overbite. Maxillary incisors significantly extruded (2.52 ± 1.02 mm) and significantly reclined (5.78 ± 0.77°), with a resultant decrease in the overjet of 1.58 ± 0.5mm. A significant intrusion of maxillary first molars with no change in their inclination was observed. The upper lip showed a significant retraction tendency to the E-plane, and a significant increase in the nasolabial angle was observed. Conclusion: The skeletally anchored NiTi extrusion arch was an effective technique in treating AOB, with no adverse effects on the molars.

RESUMO Objetivo: O objetivo deste ensaio clínico prospectivo foi avaliar as alterações dentárias e em tecidos moles que acompanham o uso de arco de extrusão de níquel-titânio (NiTi) com ancoragem esquelético na correção da mordida aberta anterior (MAA). Material e Métodos: Participaram deste estudo 20 pacientes do sexo feminino com idade média de 16,5 ± 1,5 anos e MAA dentoalveolar (média de 2,38 ± 0,7 mm). Todos os pacientes foram tratados com arco de extrusão de NiTi 0,017×0,025" superior, com auxílio de mini-implantes inseridos entre os segundos pré-molares e primeiros molares superiores bilateralmente, para atuar como ancoragem indireta. Modelos digitais tridimensionais e radiografias cefalométricas laterais foram realizados imediatamente antes da inserção do arco de extrusão (T0) e após 10 meses (T1). Testes t para amostras pareadas foram utilizados na análise dos dados, para avaliar as alterações após o tratamento (T1-T0). Um nível de significância de p< 0,05 foi usado. Resultados: A MAA foi fechada com sucesso em todos os pacientes, com aumento de 4,35 ± 0,61 mm na sobremordida. Os incisivos superiores foram significativamente extruídos (2,52 ± 1,02 mm) e significativamente reclinados (5,78 ± 0,77°), com uma consequente diminuição na sobressaliência de 1,58 ± 0,5 mm. Foi observada intrusão significativa dos primeiros molares superiores, sem alteração na sua inclinação. O lábio superior apresentou tendência significativa de retração em relação ao plano E, e foi observado aumento significativo do ângulo nasolabial. Conclusão: O arco de extrusão de NiTi esquelético foi uma técnica eficaz no tratamento da MAA, sem efeitos adversos nos molares.

Three-dimensional assessment of external apical root resorption after maxillary posterior teeth intrusion with miniscrews in anterior open bite patients

ABSTRACT Objective: The objective of this study was to assess the external apical root resorption (EARR) of the maxillary posterior teeth after intrusion with miniscrews. Methods: Fifteen patients (13 females and 2 males) with age ranging from 14.5 to 22 years (mean 18.1 ±2.03 years) were selected to participate in this study. All patients presented with anterior open bite of 3 mm or more. An intrusion force of 300 g was applied on each side to intrude the maxillary posterior teeth. Cone beam computed tomography (CBCT) scans were taken pretreatment and post-intrusion and were analyzed to evaluate the EARR. Results: The maxillary posterior teeth were intruded in average 2.79 ± 0.46 mm (p< 0.001) in 5.1 ± 1.3 months, and all examined roots showed statistically significant EARR (p< 0.05) with an average of 0.55 mm, except the distobuccal root of the left first permanent molars and both the palatal and buccal roots of left first premolars, which showed no statistically significant changes. Conclusions: The evaluated teeth presented statistically significant EARR, but clinically, due to the small magnitude, it was not considered significant. Moreover, the CBCT provided a good visualization of all roots in all three planes, and it was effective in detecting minimal degrees of EARR.

RESUMO Objetivo: o objetivo desse estudo foi verificar a existência de reabsorção radicular apical externa (RRAE) em dentes posterossuperiores após intrusão ancorada em mini-implantes. Métodos: quinze pacientes (13 mulheres e 2 homens) com a idade variando entre 14,5 e 22 anos (média de 18,1 ± 2,03 anos) foram selecionados para participar desse estudo. Todos os pacientes possuíam mordida aberta anterior de 3mm ou mais. Uma força de 300 gramas foi aplicada em cada lado para intruir os dentes posterossuperiores. Tomografias computadorizadas de feixe cônico (TCFC), adquiridas antes do tratamento e após a intrusão, foram comparadas para se avaliar a RRAE. Resultados: os dentes posterossuperiores foram intruídos em média 2,70 ± 0,46 mm (p< 0,001) em 5,1 ± 1,3 meses, e todas as raízes examinadas mostraram RRAE estatisticamente significativa (p< 0,05), com média de 0,55 mm, exceto pela raiz distovestibular dos primeiros molares permanentes esquerdos, e pelas raízes palatina e vestibular dos primeiros pré-molares esquerdos, que não apresentaram mudanças estatisticamente significativas. Conclusões: os dentes avaliados apresentaram RRAE estatisticamente significativa, a qual, porém, não foi considerada clinicamente significativa, devido à sua reduzida magnitude. Além disso, a TCFC possibilitou uma boa visualização de todas as raízes nos três planos espaciais, e foi eficaz para detecção de níveis mínimos de RRAE.

Three-dimensional assessment of external apical root resorption after maxillary posterior teeth intrusion with miniscrews in anterior open bite patients.

OBJECTIVE: The objective of this study was to assess the external apical root resorption (EARR) of the maxillary posterior teeth after intrusion with miniscrews. METHODS: Fifteen patients (13 females and 2 males) with age ranging from 14.5 to 22 years (mean 18.1 ±2.03 years) were selected to participate in this study. All patients presented with anterior open bite of 3 mm or more. An intrusion force of 300 g was applied on each side to intrude the maxillary posterior teeth. Cone beam computed tomography (CBCT) scans were taken pretreatment and post-intrusion and were analyzed to evaluate the EARR. RESULTS: The maxillary posterior teeth were intruded in average 2.79 ± 0.46 mm (p< 0.001) in 5.1 ± 1.3 months, and all examined roots showed statistically significant EARR (p< 0.05) with an average of 0.55 mm, except the distobuccal root of the left first permanent molars and both the palatal and buccal roots of left first premolars, which showed no statistically significant changes. CONCLUSIONS: The evaluated teeth presented statistically significant EARR, but clinically, due to the small magnitude, it was not considered significant. Moreover, the CBCT provided a good visualization of all roots in all three planes, and it was effective in detecting minimal degrees of EARR.

Intrusion of Lower Incisors in Deep Overbite Cases with Mini-screws.

OBJECTIVES: To evaluate the dentoskeletal effects of intrusion of the lower incisor teeth by mini-screws. MATERIAL AND METHODS: Ten patients were selected from the outpatient clinic of the Department of Orthodontics, Faculty of Dentistry, Mansoura University with Angle's Class II division I malocclusions. Age ranged from 15 to 18 years (15.4 year mean) with deep overbite (more than 1/3 the crown height of the lower incisors covered) requiring intrusion of the lower incisors. After alignment of the first molars, the second premolars ,and canines without inclusion of the lower four incisors, the cuspids were retracted on 16x22 inch stainless steel wire. For each patient, two mini-screws were inserted for anchorage for the lower incisors segment intrusion between the lateral incisor and the cuspid--one in each side and connected to a utility arch wire. RESULTS: The mean of overbite correction was 4.2 mm (p<. 05, and lower incisors were intruded significantly by a mean of 3.55 mm (p<.05). CONCLUSION: The mandibular incisors were effectively intruded by using mini-screws as orthodontic anchorage with no significant counteractive movements in the molars.

Intrusion of maxillary incisors by mini-screw anchorage of Angle Class II division 2 malocclusion cases.

OBJECTIVES: to evaluate the effects of the upper incisor teeth intrusion by mini-screw on the amount of overbite and on the dental and skeletal parameters of the jaws. MATERIAL AND METHODS: Ten patients were selected from the outpatient clinic of the Department of Orthodontics, Faculty of Dentistry, Mansoura University with Angle's Class II division 2 malocclusions. Ages ranged from 13 to 19 years with deep overbite of 4mm or more requiring intrusion of the maxillary incisors. Alignment of the upper and lower dental arches was done with a pre-adjusted edgewise technique, then a mini-screw as anchorage for the intrusion of the upper incisor segment was inserted for every patient below the anterior nasal spine connected to a utility arch wire. RESULTS: The overbite was corrected from 6 mm to 1.8 mm (p<.001) by upper incisor intrusion and the gummy smile was improved. No extrusion of upper first permanent molars was observed. CONCLUSIONS: The maxillary incisors were effectively intruded by using mini-screws as orthodontic anchorage. Good occlusion and facial esthetics were achieved with no counteractive movements in the molars.