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1.
Eur J Orthod ; 43(2): 234-240, 2021 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-32452521

RESUMO

AIM: The aim of the prospective pilot study was to analyze the biomarkers CD34, Pax7, Myf5, and MyoD for stimulation of satellite cells (SCs), which are responsible for functional adaptation. SUBJECTS AND METHODS: Forty-five Caucasian patients were consecutively recruited from the Maxillo-Facial-Surgery at TU Dresden. Eleven orthognathic Class III patients, 24 Class II patients, and 10 controls with Class I were involved in the study. Tissue samples from masseter muscle were taken from the patients pre-surgically (T1) and 7 months later (T2). Samples from controls were taken during the extraction of third molars in the mandible. Polymerase chain reaction (PCR) for relative quantification of gene expression was calculated with the delta delta cycle threshold (ΔΔCT) method. RESULTS: The results show significant differences for the marker of SC stimulation between the controls, the patient groups, males, and females. The gene expression of CD34 was post-surgically upregulated for Class III (0.35-0.77, standard deviation [SD] = 0.39, P < 0.05) in comparison with controls. For Pax7, there was a significant difference shown between the retrognathic and the prognathic group because of downregulation in Class II patients (1.64-0.76, SD = 0.55, P < 0.05). In Class III patients, there was a significant upregulation for Myf5 (0.56-1.05, SD = 0.52, P < 0.05) after surgery too. CONCLUSIONS: The significant decline of Pax7 in Class II patients indicates a deficiency of stimulated SC post-surgically. The expression of CD34 and Myf5 in Class II stayed unchanged. In contrast, there was an upregulation for all Class III patients, mainly in females, shown post-surgically. This may be one reason for weak functional adaptation and relapse in Class II patients.


Assuntos
Má Oclusão Classe III de Angle , Cirurgia Ortognática , Feminino , Humanos , Masculino , Má Oclusão Classe III de Angle/cirurgia , Músculo Masseter , Projetos Piloto , Estudos Prospectivos
2.
J Craniomaxillofac Surg ; 49(2): 93-97, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33357968

RESUMO

The aim of this prospective study was to compare the expression of the Notch receptor family with the biomarker for stimulation of satellite cells (SC), which are responsible for functional adaptation. Tissue samples from the masseter muscle were taken presurgically and 7 months later. Samples from controls came from the extraction of third molars. The expression of Notch 1 to 4 and the satellite cell markers CD34, Pax7, and MyoD1 were investigated. PCR was used for relative quantification of gene expression, which was calculated with the ΔΔCT method. The study involved 38 white patients - 10 prognathic, 18 retrognathic, and 10 orthognathic controls. The median value for Notch 1 was significantly reduced presurgically for prognathic (0.46, SD 0.45) and retrognathic (0.57, SD 0.35) patients compared with the controls. Postsurgically, Notch 2 was significantly upregulated in the prognathic group (0.55, SD 0.28/1.37, SD 0.85). Similarly, there was upregulation of Notch 3 in the prognathic group (0.33, SD 0.42/0.59, SD 1.37) and downregulation in retrognathic patients (0.59, SD 0.79/0.52, SD 0.97). Upregulations for the satellite cell markers CD34 and Pax7 were also found in prognathic patients. The significant upregulation of Notch 1-3 and CD34 in prognathics, but unchanged MyoD expression, signals high stimulation for SC and maintenance of the regeneration cell pool. A lower expression of Notch and SC in retrognathic patients could be responsible for weak functional adaptation.


Assuntos
Cirurgia Ortognática , Procedimentos Cirúrgicos Ortognáticos , Humanos , Músculo Masseter , Músculo Esquelético , Estudos Prospectivos , Receptores Notch
3.
Int Orthod ; 18(2): 317-329, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32245745

RESUMO

OBJECTIVE: The aim of this study was to determine long-term skeletal and dental changes in tooth-anchored versus Dresden bone-anchored rapid maxillary expansion using CBCT images in adolescents. MATERIALS AND METHODS: In all, 29 adolescent patients (11-17 years of age) needing skeletal expansion were randomly allocated to two different groups treated by either a Dresden bone-anchored expander or a conventional hyrax expander. Patients included did not have previous orthodontic treatment, were non-syndromic and had all teeth present in mouth. CBCT images were taken before expansion and two or more years after expansion. An independent T-test was used to determine the statistical significance between treatment groups and paired T-test was used to compare the results before and after expansion in each group. RESULTS: Neither treatment group showed overall long-term different skeletal and dental changes in the transverse, anterior-posterior and vertical planes (P<0.05). Both treatment groups showed mild asymmetric skeletal expansion, but these were clinically insignificant. CONCLUSIONS: Both expanders had similar skeletal and dental results. The greatest changes were in the transverse plane. Changes in vertical and anterior-posterior were negligible.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Maxila/anatomia & histologia , Procedimentos de Ancoragem Ortodôntica/métodos , Técnica de Expansão Palatina/instrumentação , Adolescente , Criança , Arco Dental/anatomia & histologia , Arco Dental/diagnóstico por imagem , Feminino , Humanos , Masculino , Maxila/diagnóstico por imagem , Procedimentos de Ancoragem Ortodôntica/instrumentação , Desenho de Aparelho Ortodôntico , Dente/diagnóstico por imagem
4.
Int Orthod ; 18(2): 308-316, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32057733

RESUMO

OBJECTIVE: The main aim of this randomized clinical trial was to determine 3 dimensional skeletal and dental changes six months after the use of bone-anchored versus tooth-anchored rapid maxillary expanders in adolescents. The secondary aim was to determine the symmetrical or asymmetrical expansion pattern between both appliances. MATERIALS AND METHODS: Fifty adolescents with skeletally constricted maxilla (mean age 13-14 years) were randomly assigned into: Dresden B-RME, Hyrax T-RME, or untreated control groups. CBCT scans were taken at initial and expander removal (6 months). Three-dimensional references and treatment landmarks were identified. Orthogonal distances were calculated from those landmarks. The main outcome was to compare skeletal and dental changes in each group and the secondary outcome was to verify if these changes were symmetric or not. Data was analysed using descriptive statistics and repeated measure MANCOVA and MANOVA. RESULTS: Both treatment groups showed significant skeletal and dental expansion compared to controls. T-RME group had greater mean inter-molar crown expansion (5.66mm) than the B-RME group (4.17mm). Both T-RME and B-RME groups showed significant skeletal maxillary expansion compared to controls (mean 1.27mm and 1.31mm respectively, both p<0.01), although no significant difference was found between both appliances. B-RME group showed a lower ratio of dental to skeletal expansion than T-RME group. T-RME showed a symmetrical expansion pattern, whereas the B-RME showed an asymmetrical pattern relative to mid-sagittal plane. The extent of molar crown expansion was 1.84mm greater on the TAD-side compared to the Implant-side. T-RME group showed significant anterior movement of the maxillary first premolar and molar (1.5mm, p<0.05), and vertical dental extrusion (1.8mm). No significant dental vertical or anterior-posterior changes were noted in the B-RME group. CONCLUSIONS: T-RME and B-RME produced similar amounts of skeletal expansion. B-RME group produced a lower component of dental expansion. Due to the Dresden B-RME configuration, asymmetrical expansion was noted.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Maxila/anatomia & histologia , Procedimentos de Ancoragem Ortodôntica/métodos , Técnica de Expansão Palatina/instrumentação , Adolescente , Análise de Variância , Cefalometria , Criança , Arco Dental/anatomia & histologia , Arco Dental/diagnóstico por imagem , Feminino , Humanos , Masculino , Maxila/diagnóstico por imagem , Procedimentos de Ancoragem Ortodôntica/instrumentação , Desenho de Aparelho Ortodôntico , Dente/diagnóstico por imagem
5.
Angle Orthod ; 89(5): 721-726, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30883188

RESUMO

OBJECTIVES: To determine the diagnostic value of resonance frequency analysis (RFA) in predicting palatal implant (PI) loss. MATERIALS AND METHODS: RFA values of 32 patients (study center at Mainz and Dresden) were evaluated in a prospective randomized controlled trial addressing clinical performance of two loading concepts on PI (Orthosystem, Straumann, Basel, Switzerland). Group 1: conventional loading after a 12-week healing period vs group 2: immediate loading within one week after insertion. Stability was assessed by RFA after surgical insertion (T1), one week (T2), and 12 weeks (T3) later. RESULTS: All 32 PI were clinically stable after surgical insertion; 14 PI were loaded conventionally and 18 immediately. One implant in group 1 was lost 6 weeks after insertion. One drop-out was registered in group 2. One false positive and three false negative implant stability quotients (ISQ) were observed. ISQ values of clinically stable PI in group 1 were 67.2 (SD ± 9.5) at T1, 62.3 (SD ± 11.7) at T2, and 68.2 (SD ± 5.5) at T3. Group 2 showed 67.1 (SD ± 11.7) at T1, 65.4 (SD ± 10.4) at T2, and 72.3 (SD ± 5.6) at T3. Differences between groups were not statistically significant for starting time (P = .88) and change from T1 to T2: 0.08 but were significant from T1 to T3: P = .04; (regression analysis). CONCLUSIONS: RFA had no sensitivity for prediction of stability. General decrease after primary stability and increase with secondary stability gives support for specificity. Within the limits of the study, only the diagnostic value of RFA identifying stable palatal implants could be confirmed.


Assuntos
Implantação Dentária Endóssea , Implantes Dentários , Osseointegração , Humanos , Palato , Estudos Prospectivos , Análise de Frequência de Ressonância , Falha de Tratamento , Cicatrização
6.
J Craniomaxillofac Surg ; 45(4): 547-551, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28223013

RESUMO

One third of adult patients with orthognathic surgery of a prognathic or retrognathic mandible show relapse. The sagittal split osteotomy of the mandible leads to a displacement of both parts up to 10 mm without any changes of muscle attachment. Changed mandible length needs adaptation of muscle capacity because of changed force to moment ratio. The aim of this Microarray study was to analyze the general genetic response of masseter muscle in patients with retrognathism or prognathism of the mandible six months after surgery in comparison with healthy untreated controls. We found in tissue samples from masseter muscle a reduction of different entities between patients and controls but less in retrognathic than in prognathic patients (274/429). The different entities to controls in prognathia were reduced from 1862 to 1749 but increased in retrognathia from 1070 to 1563. We have to consider that the total amount of different entities to the controls is higher in patients with prognathic mandible (7364) because of their strong genetic controlled development compared with that in patients with retrognathic mandible (4126), which is more environmentally influenced. It can be concluded that function follows form after surgical change with high inheritance. In retrognathic patients the adaptation could be delayed or the capacity of regeneration potential is not sufficient.


Assuntos
Músculo Masseter , Análise em Microsséries , Procedimentos Cirúrgicos Ortognáticos , Prognatismo/genética , Prognatismo/cirurgia , Retrognatismo/genética , Retrognatismo/cirurgia , Humanos , Músculo Masseter/crescimento & desenvolvimento
7.
Artigo em Inglês | MEDLINE | ID: mdl-23453032

RESUMO

OBJECTIVE: The objective of this study was to investigate differences in masseter metabolism by (31)P-Chemical Shift Imaging (CSI) in adult individuals with different vertical facial patterns. The clinical study should be supported by functional findings at the mRNA level after orthognathic surgery. STUDY DESIGN: Twenty-two male volunteers (mean age 24.6) were divided into a deep-bite (NL/ML 11.8 ± 2.3°) and open-bite group (NL/ML 34.1 ± 2.6°). Vertical jaw relationship, gonial angle, and masseter volume were defined and compared with the phosphate values obtained from the (31)P spectra. Student t test and regression analysis were used. RESULTS: Phosphocreatine related strongly to muscle volume (P < .001), gonial angle (P < .001), and ML/NL angle (P < .01). Pi was found to be related to gonial angle (P < .05). Muscle volume was found to be inversely related to ML/NL (P < .01) and to the gonial angle (P < .01). CONCLUSIONS: A difference in masseter muscle metabolism between long- and short-faced subjects was confirmed at rest position.


Assuntos
Espectroscopia de Ressonância Magnética , Músculo Masseter/metabolismo , Mordida Aberta/metabolismo , Sobremordida/metabolismo , Adulto , Cefalometria/métodos , Metabolismo Energético/fisiologia , Humanos , Masculino , Mandíbula/patologia , Músculo Masseter/patologia , Contração Muscular/fisiologia , Mordida Aberta/patologia , Tamanho do Órgão , Sobremordida/patologia , Fosfatos/análise , Fosfocreatina/análise , Isótopos de Fósforo , Descanso/fisiologia , Dimensão Vertical , Adulto Jovem
8.
Br J Oral Maxillofac Surg ; 51(6): 530-5, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23280152

RESUMO

Up to 30% of patients relapse after orthognathic operations, and one reason might be incomplete neuromuscular adaptation of the masticatory muscles. Displacement of the mandible in sagittal or vertical directions, or both, leads to stretching or compression of these muscles. The aim of this study was to analyse stretching factors in 35 patients with retrognathism or prognathism of the mandible (Classes II and III). Tissue samples were taken from both sides of the masseter muscle (anterior and posterior) both before and 6 months after operation. Developmental myosin heavy chains MYH3 and MYH8, the fast and slow MYH 1, 2, and 7, and cyclo-oxygenase (COX) 2, forkhead transcription factor (FOX)O3a, calcineurin, and nuclear factor of activated T cells (NFAT)1c (stretching and regeneration-specific), were analysed by real time polymerase chain reaction (PCR). Correlations of Class II and III with sagittal and vertical cephalometric measurements ANB and ML-NL-angle were examined, and the results showed significant differences in amounts of MYH8 (p<0.05), MYH1 (p<0.05), and FOXO3a (p<0.05) between the 2 groups. Regeneration factor COX2 is more dominant in Class II. Surgically, bite opening (ML/NL angle) correlated with stretching indicators FOXO3a, calcineurin, and NFAT1c only in Class II patients. This means that stretching of the masseter muscle caused by lengthening of the mandible and raising of the bite in Class II patients was more likely to lead to relapse (similar to that in patients with open bite) than in Class III patients. In conclusion, deep bite should be reduced more by incisor intrusion than by skeletal opening. The focus in these patients should be directed towards physiotherapeutic strengthening of the muscles of mastication, and more consideration should be given to change in the vertical dimension.


Assuntos
Mandíbula/cirurgia , Músculo Masseter/patologia , Fusos Musculares/patologia , Procedimentos Cirúrgicos Ortognáticos/métodos , Adaptação Fisiológica/fisiologia , Calcineurina/análise , Miosinas Cardíacas/análise , Ciclo-Oxigenase 2/análise , Proteínas do Citoesqueleto/análise , Feminino , Proteína Forkhead Box O3 , Fatores de Transcrição Forkhead/análise , Humanos , Incisivo/patologia , Masculino , Má Oclusão Classe II de Angle/cirurgia , Má Oclusão Classe III de Angle/cirurgia , Cadeias Pesadas de Miosina/análise , Fatores de Transcrição NFATC/análise , Mordida Aberta/cirurgia , Sobremordida/cirurgia , Prognatismo/cirurgia , Recidiva , Regeneração/fisiologia , Retrognatismo/cirurgia , Técnicas de Movimentação Dentária/métodos , Dimensão Vertical
9.
Am J Orthod Dentofacial Orthop ; 139(4 Suppl): S109-16, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21435528

RESUMO

INTRODUCTION: The aims of this study were to analyze changes in bone density of the midpalatal suture after surgically assisted rapid palatal expansion (SARPE) with the bone-borne Dresden Distractor (DD; ITU, Dresden, Germany) via computed tomography (CT) and to compare of preoperative surgical findings with a control group. METHODS: Sixteen adult patients (mean age 24.5 years) underwent axial CT scans before and 7 months after SARPE. CT image fusion was performed for the midpalatal suture bone. Sixty-six controls (mean age 25.7 years) served for comparing age-related bone density. Bone structure and density were assessed in the coronal plane at the anterior, median, and posterior levels. RESULTS: Highest density was found in the posterior part (1046 Hounsfield units [HU]) before expansion. Seven months after SARPE, bone density was 48% (anterior), 53% (median), and 75% (posterior) compared with preoperative values. The control group showed fairly equal Hounsfield units (889 HU to 900 HU) in all parts. CONCLUSIONS: Seven months after SARPE, the midpalatal suture's density achieves just one half to three quarters of the pretreatment values. To maintain the resistance against forces from the unsplit posterior part, the retention time should be lengthened.


Assuntos
Densidade Óssea , Má Oclusão/cirurgia , Técnica de Expansão Palatina , Palato Duro/fisiopatologia , Palato Duro/cirurgia , Adolescente , Adulto , Estudos de Casos e Controles , Suturas Cranianas/diagnóstico por imagem , Suturas Cranianas/patologia , Análise do Estresse Dentário , Feminino , Humanos , Masculino , Má Oclusão/diagnóstico por imagem , Má Oclusão/patologia , Procedimentos Cirúrgicos Ortognáticos , Osteogênese por Distração , Palato Duro/diagnóstico por imagem , Palato Duro/patologia , Estudos Prospectivos , Reprodutibilidade dos Testes , Prevenção Secundária , Estatísticas não Paramétricas , Tomografia Computadorizada por Raios X , Adulto Jovem
10.
Eur J Orthod ; 33(5): 521-7, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21097534

RESUMO

The purpose of the study was to measure the in vitro shear bond strength (SBS) of metal brackets after multiple bonding and debonding with and without repeated etching. One hundred and twenty extracted premolars were divided into three equal groups. In group 1, the brackets were bonded and debonded three times with repeated enamel etching and in groups 2 and 3 without repeated etching. In group 2, all composite remnants were removed before bonding, while in group 3, the remnants were levelled. Analysis of variance was used to determine significant differences in SBS with Bonferroni adjustment for the multiple testing procedures. The results showed that in group 1, the mean SBS was 11.69 MPa (SD 2.65) at the first, 14.30 MPa (SD 2.69) at the second, and 12.19 MPa (SD 2.26) at the third debonding. In group 2, SBS decreased from 12.57 MPa (SD 2.54) to below 8.0 MPa. In group 3, SBS remained constant from the first (11.93 MPa; SD 2.14) to the second (12.06 MPa; SD 1.65) debonding and only decreased significantly to 9.74 MPa (SD 1.80) at the third debonding. Less composite remained on the teeth after each debonding sequence. This was characterized by a shift from adhesive remnant index (ARI) scores 2 and 3 after the first debonding to ARI scores 1 and 2 after the second debonding to predominantly scores 0 and 1 after the third debonding. After bracket loss and levelling of composite remnants, the SBS is sufficient for application of orthodontic forces. Repeated etching may involve a higher risk of enamel tear-outs during debonding.


Assuntos
Colagem Dentária/métodos , Esmalte Dentário/ultraestrutura , Corrosão Dentária/efeitos adversos , Braquetes Ortodônticos , Resistência ao Cisalhamento , Resinas Compostas/efeitos adversos , Cimentos Dentários/efeitos adversos , Descolagem Dentária/efeitos adversos , Esmalte Dentário/lesões , Corrosão Dentária/métodos , Análise do Estresse Dentário , Humanos , Retratamento
11.
J Craniomaxillofac Surg ; 39(6): 401-6, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20673635

RESUMO

INTRODUCTION: A microarray study showed an increase of developmental myosin heavy chain (MyHC) mRNA in the masseter muscle after surgery. The aim of the study was to determine the expression of the embryonic MYH3 and perinatal MYH8 for use as potential marker for muscle adaptation after orthognathic surgery. MATERIAL AND METHODS: 24 adult patients with a prognathic (11) or retrognathic (13) mandible were involved in the study. 192 biopsies were taken from two parts of the muscles presurgically and 6 months following. The expression of MYH3 and MYH8 were quantified using real-time polymerase chain reaction (RT-PCR). Absolute quantification was done by CT-values. RESULTS: MYH3 was up-regulated in prognathia (8.5, P<0.001) and in retrognathia (2.8, P<0.043). MYH8 was up-regulated in retrognathia only (4.0, P<0.063) and down-regulated in prognathia (-1.6). MYH3 values correlated in retrognathic patients (P<0.005) before and after surgery. CONCLUSION: MYH3 and MYH8 could play a role in functional adaptation after orthognathic surgery and orofacial orthopaedics.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Mandíbula/cirurgia , Músculo Masseter/metabolismo , Cadeias Pesadas de Miosina/biossíntese , Procedimentos Cirúrgicos Ortognáticos , Adaptação Fisiológica/genética , Adulto , Proteínas do Citoesqueleto/biossíntese , Humanos , Má Oclusão Classe II de Angle/cirurgia , Má Oclusão Classe III de Angle/cirurgia , Mandíbula/anormalidades , Músculo Masseter/fisiologia , Cadeias Pesadas de Miosina/genética , Isoformas de Proteínas/genética , Reação em Cadeia da Polimerase em Tempo Real , Estatísticas não Paramétricas
12.
Clin Oral Investig ; 15(4): 495-502, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20383544

RESUMO

This study aims to analyze the clinical performance of two loading concepts on second-generation palatal implants (Orthosystem, Straumann, Basel, Switzerland) in a prospective multicenter randomized controlled clinical trial. At the time of this interim analysis, 41 patients have been randomized on a 1:1 basis to one of two treatment groups. Group 1 underwent conventional loading of palatal implants after a healing period of 12 weeks (gold standard) while group 2 underwent immediate implant loading within 1 week after implant insertion. We report initial results at 6 months after functional loading. The primary outcome parameter was implant success (no implant mobility, no implant loss). The implants in both groups were initially stable at the time of insertion, and all were eligible for randomization. Twenty-two patients (group 1) were subjected to conventional implant loading after 12 weeks while 19 patients (group 2) received immediate functional loading within the first week after insertion. Direct (e.g. distal jet appliances) as well as indirect forms of anchorage (conventional or modified transpalatal arch) were used. The magnitude of orthodontic forces ranged between 1 and 4 N for the immediate loading group and between 1 and 5 N for the conventional loading group. One implant in group 1 was lost during the healing phase. One dropout was registered in group 2. Thirty-nine implants were functionally loaded for over 6 months now. These preliminary data provide first evidence of the fact that immediate loading of palatal implants yields equivalent success rates as conventional loading to 4 N after 6 months.


Assuntos
Implantes Dentários , Carga Imediata em Implante Dentário/métodos , Procedimentos de Ancoragem Ortodôntica/métodos , Palato Duro/cirurgia , Condicionamento Ácido do Dente/métodos , Adolescente , Adulto , Idoso , Criança , Corrosão Dentária/métodos , Planejamento de Prótese Dentária , Feminino , Seguimentos , Humanos , Masculino , Má Oclusão/classificação , Má Oclusão/terapia , Pessoa de Meia-Idade , Procedimentos de Ancoragem Ortodôntica/instrumentação , Desenho de Aparelho Ortodôntico , Aparelhos Ortodônticos , Osseointegração/fisiologia , Estudos Prospectivos , Estresse Mecânico , Propriedades de Superfície , Técnicas de Movimentação Dentária/instrumentação , Técnicas de Movimentação Dentária/métodos , Resultado do Tratamento , Adulto Jovem
13.
J Orofac Orthop ; 71(4): 273-80, 2010 Jul.
Artigo em Inglês, Alemão | MEDLINE | ID: mdl-20676814

RESUMO

AIM: To analyze the spectrum of indications for second-generation palatal implants in relation to two different loading concepts in a prospective, multicenter, randomized controlled trial (RCT). PATIENTS AND METHODS: Forty-one patients were recruited to the study from 2006 to 2009. All implants (Orthosystem, Straumann, Basel, Switzerland; dimensions: 4.1 mm x 4.2 mm) were inserted in the median or paramedian region of the anterior palate, and each patient was randomized to one of two loading groups (immediate loading within the first week after insertion versus conventional loading after a 12-week healing phase). In this interim evaluation, we report preliminary results obtained six months after functional loading. RESULTS: All palatal implants were primarily stable at the time of insertion. One implant loss (12 weeks after surgical insertion) was documented in the cohort subjected to conventional loading, and one patient dropped out of the immediate-loading group. At the time of this investigation, 39 palatal implants are experiencing functional loads. Using both loading concepts, we had various orthodontic objectives, such as intrusion of anterior and/or posterior teeth, and the mesialization and distalization of posterior teeth. Both loading groups presented nearly identical indications, and the distribution of direct vs. indirect anchorage forms was also very similar during the active treatment. CONCLUSION: Comparison of the two treatment concepts revealed no clinical differences in implant stability. Patients undergoing immediate-loading therapy were subject to no limitations regarding indications at 6 months after functional loading compared with the patients who experienced conventional loading.


Assuntos
Implantes Dentários , Arcada Edêntula/cirurgia , Palato/cirurgia , Adolescente , Adulto , Idoso , Criança , Planejamento de Prótese Dentária , Análise de Falha de Equipamento , Feminino , Alemanha , Humanos , Arcada Edêntula/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Radiografia , Resultado do Tratamento , Adulto Jovem
14.
Am J Orthod Dentofacial Orthop ; 137(6): 782-9, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20685533

RESUMO

INTRODUCTION: The purposes of this study were to detect, locate, and examine the changes in transverse nasal width, area, and volume from bone-borne, surgically assisted rapid maxillary expansion (SARME) with the Dresden distractor by using computer tomography (CT). METHODS: Sixteen patients (average age, 28.7 years) underwent axial CT scanning before and 6 months after SARME. They also underwent CT fusion on specific bony structures. The nasal bone width was examined in the coronal plane. The cross-sectional images of the nasal cavity were taken of the area surrounding the apertura piriformis, the choanae, and in between. We calculated cross-sectional areas and nasal volume according to these data. RESULTS: All but 2 patients had an increase in nasal volume of at least 5.1% (SD, 4.6%). The largest value of 35.3% (SD, 45.8%) was measured anteriorly on the nasal floor, decreasing cranially and posteriorly. This correlated with the V-shaped opening of the sutura palatina. There was no significant correlation between increase in nasal volume and transversal expansion. CONCLUSIONS: Because most of the air we breathe passes over the lower nasal floor, SARME is likely to improve nasal breathing.


Assuntos
Má Oclusão/cirurgia , Nariz/anatomia & histologia , Osteogênese por Distração/métodos , Técnica de Expansão Palatina , Palato Duro/cirurgia , Adolescente , Adulto , Feminino , Humanos , Imageamento Tridimensional , Masculino , Osso Nasal/anatomia & histologia , Cavidade Nasal/anatomia & histologia , Nasofaringe/anatomia & histologia , Nariz/diagnóstico por imagem , Tomografia Computadorizada Espiral , Adulto Jovem
15.
Biomed Tech (Berl) ; 55(1): 39-45, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20128744

RESUMO

Rapid palatal expansion is indicated in the orthopedic treatment of transverse maxillary deficiency for correction of severe crossbite. The fixation of the appliance at the tooth crowns leads to more tipping connected with resorptions at the buccal cortical bone, fenestrations and gingival retraction. The aim of the present study was focused on the improvement of bodily movement and optimization of the surgical osteotomy (Glassman's technique) in adult patients with application of the Dresden Distractor (DD). In 18 patients, the new method with a special mechanism of adaptation involving minimized surgical intervention and direct fixation of the hyrax screw by one implant and one bone screw was tested. The implants were loaded directly by activation of the hyrax screw two times per day. CT scans were taken before and 6 months after insertion of the DD. In the horizontal and vertical planes there was a V-shaped opening of the suture in anterior and cranial direction, corroborating previous studies. Dental arch also showed this V-shape, indicating tooth protection. DD is a suitable minimally invasive tooth-independent bone-borne expansion method, protecting teeth and causing skeletal as well as dental effect with tipping reduced by 10 degrees.


Assuntos
Parafusos Ósseos , Procedimentos Cirúrgicos Minimamente Invasivos/instrumentação , Técnica de Expansão Palatina/instrumentação , Adolescente , Adulto , Análise de Falha de Equipamento , Feminino , Humanos , Masculino , Projetos Piloto , Desenho de Prótese , Resultado do Tratamento , Adulto Jovem
16.
J Orofac Orthop ; 70(4): 306-17, 2009 Jul.
Artigo em Inglês, Alemão | MEDLINE | ID: mdl-19649578

RESUMO

OBJECTIVE: Aim of this study was to detect the changes in nasal volume due to bone-borne, surgically-assisted rapid palatal expansion (RPE) with the Dresden Distractor using computed tomography (CT). MATERIALS AND METHODS: 17 patients (mean age 28.8) underwent axial CT scanning before and 6 months after RPE. The nasal bone width was examined in the coronal plane. Cross-sectional images of the nasal cavity were taken of the area surrounding the piriform aperture, choanae and in between. Bony nasal volume was computed by connecting the three cross-sectional areas. RESULTS: All but two patients showed a 4.8% increase in nasal volume (SD 4.6%). The highest value, 33.3% (SD 45.1%), was measured anteriorly at the level of the nasal floor. This correlated with the midpalatal suture's V-shaped opening. There was no significant correlation between an increase in nasal volume and transverse dental arch expansion. CONCLUSION: As most of the air we breathe passes the lower nasal floor, an improvement in nasal breathing is likely.


Assuntos
Má Oclusão/terapia , Nariz/diagnóstico por imagem , Procedimentos Cirúrgicos Bucais/métodos , Osteogênese por Distração/instrumentação , Técnica de Expansão Palatina , Tomografia Computadorizada por Raios X/métodos , Adulto , Terapia Combinada , Feminino , Humanos , Masculino , Má Oclusão/diagnóstico , Tamanho do Órgão , Osteogênese por Distração/métodos , Resultado do Tratamento
17.
Dent Traumatol ; 25(2): 233-7, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19191824

RESUMO

UNLABELLED: The anterior maxilla is the most traumatized region during childhood and tooth loss is frequently involved. Space closure with implants is contraindicated in growing patients and maintenance of space is necessary over a long period. Transplantation of premolars from the mandible with two-third to three-quarter root formation wide open foramen provides the best prognosis for permanent survival. CASE REPORT: This report describes the management of a 10 year old girl with autotransplantation to replace an upper incisor by a lower premolar under consideration of special care for the periodontal ligament during surgical procedure. A 3-D imaging with digital volume tomography (DVT) was used 20 months after transplantation to evaluate the periodontal morphology. DISCUSSION: Autotransplantation of premolars with incomplete root formation to replace maxillary incisor is a treatment alternative after traumatic loss of teeth. There were no signs of pathosis like resorption or ankylosis and a normal periodontal space demonstrated with DVT. There is no need for endodontic treatment before transplantation. In this case of autotransplantation of a premolar, the DVT after 20 months gives evidence of a successful regeneration of the periodontal ligament.


Assuntos
Dente Pré-Molar/transplante , Maxila/cirurgia , Ligamento Periodontal/transplante , Avulsão Dentária/cirurgia , Raiz Dentária/crescimento & desenvolvimento , Dente Pré-Molar/diagnóstico por imagem , Criança , Tomografia Computadorizada de Feixe Cônico , Feminino , Humanos , Imageamento Tridimensional , Incisivo/lesões , Maxila/diagnóstico por imagem , Fechamento de Espaço Ortodôntico/métodos , Contenções Periodontais , Raiz Dentária/transplante , Transplante Autólogo , Resultado do Tratamento
18.
Artigo em Inglês | MEDLINE | ID: mdl-18567511

RESUMO

Patients with prognathism and retrognathism show extensive morphologic changes after orthognathic surgery. The inability of muscles to adapt adequately might be one reason for observed relapses. The aim of this prospective study was to analyze the regulation of functional genes after surgery and changes in myosin heavy chain (MyHC) isoform expression, a potential molecular marker profile for inadequate muscle adaptation. 29 adult patients with prognathic and retrognathic mandibles were involved. A total of 232 muscle biopsies were taken from both masseter muscles presurgically and 6 months later. The mRNA expression of "mechano growth factor" (MGF), myostatin, and 3 MyHC isoforms were quantified by real-time polymerase chain reaction. The MGF mRNA was significantly up-regulated (P < .005), whereas myostatin mRNA showed no significant regulation. There was a shift in MyHC isoform expression. The MyHC-I mRNA was decreased (P < .005), whereas MyHC-IIa mRNA was increased (P < .005). The coherence of increased MGF expression and MyHC isoform shift 6 months after orthognatic surgery indicates an adequate muscle adaptation and higher mastication activity.


Assuntos
Fator de Crescimento Insulin-Like I/biossíntese , Mandíbula/cirurgia , Músculo Masseter/metabolismo , Cadeias Pesadas de Miosina/biossíntese , Miostatina/biossíntese , Procedimentos Cirúrgicos Bucais , Adaptação Fisiológica , Adolescente , Adulto , Feminino , Regulação da Expressão Gênica , Humanos , Masculino , Má Oclusão Classe II de Angle/cirurgia , Má Oclusão Classe III de Angle/cirurgia , Mandíbula/anormalidades , Prognatismo/cirurgia , Estudos Prospectivos , Isoformas de Proteínas , Retrognatismo/cirurgia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Adulto Jovem
19.
Am J Orthod Dentofacial Orthop ; 133(5): 762-70, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18456153

RESUMO

The maxillary canines are important teeth in terms of esthetics and function. This case report describes the orthodontic treatment of a 12-year-old girl whose Class II malocclusion was complicated by an impacted maxillary canine and peg-shaped lateral incisors. Despite dilaceration of the root, the impacted canine was brought into alignment. The peg-shaped lateral incisors were extracted, and the spaces were closed, resulting in favorable esthetics and good occlusion in the long term.


Assuntos
Má Oclusão Classe II de Angle/terapia , Anormalidades Dentárias/complicações , Raiz Dentária/anormalidades , Dente Impactado/terapia , Criança , Dente Canino/anormalidades , Dente Canino/fisiopatologia , Feminino , Humanos , Incisivo/anormalidades , Incisivo/cirurgia , Má Oclusão Classe II de Angle/complicações , Maxila , Extrusão Ortodôntica , Fechamento de Espaço Ortodôntico , Extração Dentária , Dente Impactado/complicações
20.
Orthod Fr ; 79(2): 127-35, 2008 Jun.
Artigo em Francês | MEDLINE | ID: mdl-18505675

RESUMO

Rapid palatal expansion is indicated in the orthopedic treatment of transverse maxillary deficiency for correction of severe crossbite. The fixation of the appliance at the teeth crowns leads to more tipping at the two halves of the maxilla than bodily transverse movement. Additional resorptions at the buccal cortical bone with fenestrations and gingival retraction were observed. The aim of the present study was focused on the improvement of bodily movement and optimization of the surgical osteotomy (Glassman's technique) in adult patients with application of the Dresden Distractor (DD). In 15 patients, the new method involving minimized surgical intervention and direct fixation of the hyrax screw by one implant and one bone screw was tested. The implants were loaded directly by activation of the screw two times per day. CT scans were taken before and six month after insertion of the DD. In the horizontal and the vertical planes there was a V-shaped opening of the suture in anterior, respective cranial direction, corroborating previous studies. Dental arch showed this V-shape as well, indicating tooth protection. If forces are transferred via teeth the progressive increase of skeletal resistance in anterior to posterior direction lead to dental tipping. DD is a suitable minimal invasive tooth-independent bone-borne expansion method, protecting teeth and causing skeletal as well as dental effect with 10 degree less tipping and as a precondition for stable post surgical occlusion.


Assuntos
Má Oclusão/terapia , Procedimentos de Ancoragem Ortodôntica/instrumentação , Desenho de Aparelho Ortodôntico , Osteogênese por Distração/instrumentação , Técnica de Expansão Palatina/instrumentação , Adolescente , Adulto , Parafusos Ósseos , Implantes Dentários , Análise do Estresse Dentário , Humanos , Aparelhos Ortodônticos , Palato Duro/cirurgia , Torque
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