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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Two and three dimensional cephalometric assessment of dental and skeletal changes following orthodontic treatment with Damon passive self-ligating system

Ehsani, Sayeh 06 1900 (has links)
Objectives: The aim of this study was to evaluate dental and/or skeletal changes following orthodontic treatment with Damon self-ligating (SL) brackets in non-extraction patients. Methods: Frontal and lateral cephalomteric radiographs of 20 patients before and after non-extraction treatment with Damon SL brackets were analyzed in a three-dimensional analysis computer program (3DCeph, UIC, IL., USA). Changes of intermolar and intercanine distances, incisor positions and maxillary basal bone width of Damon treated subjects were compared to corresponding untreated controls (Bolton templates). Comparisons between the two groups were made with Nonparametric (Mann-Whitney U) test. Results and Conclusions: Transverse changes in distances between crowns of upper and lower first molars and canines in Damon group were similar to untreated individuals (P >0.01). However, in Damon group distances between roots of upper molars and lower canines increased 4.59 and 3.49 mm respectively, compared with 0.8 and -0.01 mm in the Control group (P <0.001, P= 0.001). Lingual root torque of upper incisors and proclination of lower incisors were larger in the Damon group (P<0.05). Damon treatment did not result in buccal tipping of molar crowns or maxillary base width increase (P>0.05). Overall, teeth alignment with Damon system was accomplished with a combination of arch width changes and incisor proclination and/or lingual root torque.
2

Two and three dimensional cephalometric assessment of dental and skeletal changes following orthodontic treatment with Damon passive self-ligating system

Ehsani, Sayeh Unknown Date
No description available.
3

Avaliação do posicionamento de caninos superiores permanentes na fase da dentadura mista em relação à largura do arco dentário e ao espaço na região anterior / Evaluation of the maxillary canines position in mixed-dentition and width and anterior space relationship

Suga, Selma Sano 19 March 2008 (has links)
Este estudo avaliou o posicionamento de caninos superiores permanentes em relação à largura do arco dentário superior e ao espaço na região anterior em pacientes na fase da dentadura mista. Foram analisados radiografias panorâmicas e modelos de estudo pré-tratamento de pacientes sem caninos deslocados (n = 68; 34 do gênero masculino; 34 do gênero feminino). A amostra foi dividida em idade e gênero. A largura do arco dentário e o espaço na região anterior entre os incisivos permanentes foram medidos. A posição e a inclinação do canino na radiografia panorâmica foram avaliadas em relação à linha mediana. Os resultados deste estudo mostram que não houve diferenças no posicionamento dos caninos permanentes em relação às variáveis analisadas. A média da angulação do canino superior em relação à linha mediana foi 6,2o e 10o para o gênero feminino e 9,2o e 11o para o masculino, respectivamente para o lado direito e esquerdo. / This study investigated the correlation between maxillary dental arch width, anterior space and the position of canines in patients during the mixed-dentition stage. Pretreatment Panoramic radiographs and dental casts were evaluated of randomly selected patients in the mixed dentition without maxillary canines displaced (n = 68; male, 34; female, 34). This sample was matched according to sex and age. Arch widths between the maxillary canines deciduous and anterior space between permanent incisors were measured and recorded. The position and inclination of canine on panoramic radiography was investigated. The results of this study showed that there are similarities in the position of the permanent canines in all cases and in both gender. The average of the canine\'s angulation to the mid-sagital plane was 6,2o and 10o for female and 9,2o and 11o for male, respectively to the right and left side.
4

Alterações das dimensões dos arcos dentários e das inclinações dos incisivos produzidas pelo Sistema Damon / Arch width and incisor torque changes produced by the Damon System

Valeria Matos Bezerra 19 December 2012 (has links)
PROPOSIÇÃO: O objetivo deste trabalho foi descrever as alterações das dimensões dos arcos dentários e das inclinações dos incisivos produzidas pelo Sistema Damon, durante a fase de alinhamento e nivelamento. Outro objetivo foi verificar a correlação destas alterações com o padrão de crescimento dos indivíduos. MATERIAL E MÉTODOS: modelos de estudo, telerradiografias convencionais e telerradiografias reconstruídas a partir de tomografias computadorizadas cone-beam de 22 casos tratados com o bráquetes Damon 3MXTM foram avaliados durante a fase de alinhamento e nivelamento. Os modelos de estudo foram obtidos ao início do tratamento (T0), após a primeira troca de fio (T1) e na inserção do fio de aço 0,019 x 0,025 (T2). Foram verificados os comprimentos de arco e as dimensões transversais nas regiões de caninos, primeiros e segundos pré-molares e primeiros molares mensuradas a partir das pontas de cúspides e margens gengivais linguais dos dentes, a cada etapa. Nas telerradiografias foram verificadas as alterações das inclinações dos incisivos inferiores e superiores, bem como o padrão de crescimento dos indivíduos. RESULTADOS: os comprimentos dos arcos e todas as distâncias transversais apresentaram aumentos significantes, com exceção da distância intercervical dos caninos superiores; houve aumento significante das inclinações vestibulares dos incisivos superiores e inferiores; o padrão de crescimento dos pacientes apresentou correlação significante com os aumentos transversais na região de pré-molares inferiores. CONCLUSÕES: o alinhamento e nivelamento de casos tratados sem extrações com o uso do Sistema Damon resultou no aumento significante das dimensões dos arcos dentários e das inclinações dos incisivos para vestibular. / OBJECTIVE: This study aimed to evaluate the dental arch widths and incisor torque changes produced by the Damon System during leveling and alignment. Other objective was to verify the correlation between these changes and the growth pattern. MATHERIAL AND METHODS: study casts and lateral radiographs derived from cone-beam computed tomographies of 22 subjects treated with Damon 3MXTM brackets were evaluated. The study casts were obtained at the start of treatment (T0), the first archwire change (T1), and the placement of the final 0,019 x 0,025-in archwire (T2). Arch depth and widths (intercanine, interpremolar and intermolar) were assessed at each stage. The incisor torques changes and the growth pattern were measured on the cephalometric records at T0 and T2. RESULTS: There was significant increase of the arch depths and lateral expansion of the arches for all measures, except for the intercervical of maxillary canines. The maxillary and mandibular incisors were significantly tipped labially; the growth pattern showed significant correlation with the lateral increases in lower premolars region. CONCLUSIONS: nonextraction cases treated with Damon System show significant increases in arch dimensions and incisors proclination.
5

Alterações das dimensões dos arcos dentários e das inclinações dos incisivos produzidas pelo Sistema Damon / Arch width and incisor torque changes produced by the Damon System

Bezerra, Valeria Matos 19 December 2012 (has links)
PROPOSIÇÃO: O objetivo deste trabalho foi descrever as alterações das dimensões dos arcos dentários e das inclinações dos incisivos produzidas pelo Sistema Damon, durante a fase de alinhamento e nivelamento. Outro objetivo foi verificar a correlação destas alterações com o padrão de crescimento dos indivíduos. MATERIAL E MÉTODOS: modelos de estudo, telerradiografias convencionais e telerradiografias reconstruídas a partir de tomografias computadorizadas cone-beam de 22 casos tratados com o bráquetes Damon 3MXTM foram avaliados durante a fase de alinhamento e nivelamento. Os modelos de estudo foram obtidos ao início do tratamento (T0), após a primeira troca de fio (T1) e na inserção do fio de aço 0,019 x 0,025 (T2). Foram verificados os comprimentos de arco e as dimensões transversais nas regiões de caninos, primeiros e segundos pré-molares e primeiros molares mensuradas a partir das pontas de cúspides e margens gengivais linguais dos dentes, a cada etapa. Nas telerradiografias foram verificadas as alterações das inclinações dos incisivos inferiores e superiores, bem como o padrão de crescimento dos indivíduos. RESULTADOS: os comprimentos dos arcos e todas as distâncias transversais apresentaram aumentos significantes, com exceção da distância intercervical dos caninos superiores; houve aumento significante das inclinações vestibulares dos incisivos superiores e inferiores; o padrão de crescimento dos pacientes apresentou correlação significante com os aumentos transversais na região de pré-molares inferiores. CONCLUSÕES: o alinhamento e nivelamento de casos tratados sem extrações com o uso do Sistema Damon resultou no aumento significante das dimensões dos arcos dentários e das inclinações dos incisivos para vestibular. / OBJECTIVE: This study aimed to evaluate the dental arch widths and incisor torque changes produced by the Damon System during leveling and alignment. Other objective was to verify the correlation between these changes and the growth pattern. MATHERIAL AND METHODS: study casts and lateral radiographs derived from cone-beam computed tomographies of 22 subjects treated with Damon 3MXTM brackets were evaluated. The study casts were obtained at the start of treatment (T0), the first archwire change (T1), and the placement of the final 0,019 x 0,025-in archwire (T2). Arch depth and widths (intercanine, interpremolar and intermolar) were assessed at each stage. The incisor torques changes and the growth pattern were measured on the cephalometric records at T0 and T2. RESULTS: There was significant increase of the arch depths and lateral expansion of the arches for all measures, except for the intercervical of maxillary canines. The maxillary and mandibular incisors were significantly tipped labially; the growth pattern showed significant correlation with the lateral increases in lower premolars region. CONCLUSIONS: nonextraction cases treated with Damon System show significant increases in arch dimensions and incisors proclination.
6

Avaliação do posicionamento de caninos superiores permanentes na fase da dentadura mista em relação à largura do arco dentário e ao espaço na região anterior / Evaluation of the maxillary canines position in mixed-dentition and width and anterior space relationship

Selma Sano Suga 19 March 2008 (has links)
Este estudo avaliou o posicionamento de caninos superiores permanentes em relação à largura do arco dentário superior e ao espaço na região anterior em pacientes na fase da dentadura mista. Foram analisados radiografias panorâmicas e modelos de estudo pré-tratamento de pacientes sem caninos deslocados (n = 68; 34 do gênero masculino; 34 do gênero feminino). A amostra foi dividida em idade e gênero. A largura do arco dentário e o espaço na região anterior entre os incisivos permanentes foram medidos. A posição e a inclinação do canino na radiografia panorâmica foram avaliadas em relação à linha mediana. Os resultados deste estudo mostram que não houve diferenças no posicionamento dos caninos permanentes em relação às variáveis analisadas. A média da angulação do canino superior em relação à linha mediana foi 6,2o e 10o para o gênero feminino e 9,2o e 11o para o masculino, respectivamente para o lado direito e esquerdo. / This study investigated the correlation between maxillary dental arch width, anterior space and the position of canines in patients during the mixed-dentition stage. Pretreatment Panoramic radiographs and dental casts were evaluated of randomly selected patients in the mixed dentition without maxillary canines displaced (n = 68; male, 34; female, 34). This sample was matched according to sex and age. Arch widths between the maxillary canines deciduous and anterior space between permanent incisors were measured and recorded. The position and inclination of canine on panoramic radiography was investigated. The results of this study showed that there are similarities in the position of the permanent canines in all cases and in both gender. The average of the canine\'s angulation to the mid-sagital plane was 6,2o and 10o for female and 9,2o and 11o for male, respectively to the right and left side.
7

Changes in arch dimensions after extraction and non-extraction orthodontic treatment

MacKriel, Earl Ari. January 2008 (has links)
Magister Scientiae Dentium - MSc(Dent) / The aim of this study was to determine whether there are changes in the interdental arch widths and arch lengths of the mandibular and maxillary arches during nonextraction and extraction orthodontic treatment. The records of 78 patients treated by one orthodontist were used for this study. Three treatment groups were selected: a nonextraction group (Group NE), a group treated with extraction of maxillary and mandibular first premolars (Group 44), and a group treated with extraction of maxillary first premolars and mandibular second premolars (Group 45). The arch width measurements were measured in the inter-canine, inter-premolar and inter-molar areas. The arch length was measured as the sum of the left and right distances from mesial anatomic contact points of the first permanent molars to the contact point of the central incisors or to the midpoint between the central incisor contacts, if spaced.Statistical analysis included descriptive statistics of the data, analysis of the correlation matrices, Wilcoxon Signed Rank tests and Kruskal-Wallis tests of the changes which occurred during treatment. The intercanine widths in the mandible and maxilla increased during treatment in all three groups, with the extraction groups showing a greater increase than Group NE (p<0.05). In Group NE the mandibular arch length increased (p>0.05), while the maxillary arch length remained essentially unchanged. Both extraction groups showed decreases in arch length in the dentitions (p<0.05), with greater decreases occurring in the maxilla. The difference in arch length change between the two extraction groups was not significant (p<0.05). The inter-canine arch width increased in all three treatment groups, more so in the two extraction groups. From this it is evident that extraction treatment does not necessarily lead to narrowing of the dental arches in the canine region. The inter-second premolar arch width decreased in both extraction groups. Non-extraction treatment resulted in an increase in the inter-premolar and inter-molar arch widths. / South Africa
8

Changes in arch dimensions after extraction and non-extraction orthodontic treatment.

MacKriel, Earl Ari. January 2008 (has links)
<p>The aim of this study was to determine whether there are changes in the interdental arch widths and arch lengths of the mandibular and maxillary arches during nonextraction and extraction orthodontic treatment. The records of 78 patients treated by one orthodontist were used for this study. Three treatment groups were selected: a nonextraction group (Group NE), a group treated with extraction of maxillary and mandibular first premolars (Group 44), and a group treated with extraction of maxillary first premolars and mandibular second premolars (Group 45). The arch width measurements were measured in the inter-canine, inter-premolar and inter-molar areas. The arch length was measured as the sum of the left and right distances from mesial anatomic contact points of the first permanent molars to the contact point of the central incisors or to the midpoint between the central incisor contacts, if spaced.</p> <p>Statistical analysis included descriptive statistics of the data, analysis of the correlation matrices, Wilcoxon Signed Rank tests and Kruskal-Wallis tests of the changes which occurred during treatment. The intercanine widths in the mandible and maxilla increased during treatment in all three groups, with the extraction groups showing a greater increase than Group NE (p&lt / 0.05). In Group NE the mandibular arch length increased (p&lt / 0.05), while the maxillary arch length remained essentially unchanged. Both extraction groups showed decreases in arch length in the dentitions (p&lt / 0.05), with greater decreases occurring in the maxilla. The difference in arch length change between the two extraction groups was not significant (p&gt / 0.10). The inter-canine arch width increased in all three treatment groups, more so in the two extraction groups. From this it is evident that extraction treatment does not necessarily lead to narrowing of the dental arches in the canine region. The inter-second premolar arch width decreased in both extraction groups. Non-extraction treatment resulted in an increase in the inter-premolar and inter-molar arch widths.</p>
9

Changes in arch dimensions after extraction and non-extraction orthodontic treatment.

MacKriel, Earl Ari. January 2008 (has links)
<p>The aim of this study was to determine whether there are changes in the interdental arch widths and arch lengths of the mandibular and maxillary arches during nonextraction and extraction orthodontic treatment. The records of 78 patients treated by one orthodontist were used for this study. Three treatment groups were selected: a nonextraction group (Group NE), a group treated with extraction of maxillary and mandibular first premolars (Group 44), and a group treated with extraction of maxillary first premolars and mandibular second premolars (Group 45). The arch width measurements were measured in the inter-canine, inter-premolar and inter-molar areas. The arch length was measured as the sum of the left and right distances from mesial anatomic contact points of the first permanent molars to the contact point of the central incisors or to the midpoint between the central incisor contacts, if spaced.</p> <p>Statistical analysis included descriptive statistics of the data, analysis of the correlation matrices, Wilcoxon Signed Rank tests and Kruskal-Wallis tests of the changes which occurred during treatment. The intercanine widths in the mandible and maxilla increased during treatment in all three groups, with the extraction groups showing a greater increase than Group NE (p&lt / 0.05). In Group NE the mandibular arch length increased (p&lt / 0.05), while the maxillary arch length remained essentially unchanged. Both extraction groups showed decreases in arch length in the dentitions (p&lt / 0.05), with greater decreases occurring in the maxilla. The difference in arch length change between the two extraction groups was not significant (p&gt / 0.10). The inter-canine arch width increased in all three treatment groups, more so in the two extraction groups. From this it is evident that extraction treatment does not necessarily lead to narrowing of the dental arches in the canine region. The inter-second premolar arch width decreased in both extraction groups. Non-extraction treatment resulted in an increase in the inter-premolar and inter-molar arch widths.</p>
10

Die sagittale Kompensationskurve - Eine Untersuchung ihrer Veränderung und Abhängigkeit von Zahnbogenlänge, -breite und -symmetrie anhand multipel erstellter Klasse-I-Verzahnungen / The sagittal compensation curve - A study of the variation and function of arch length, width and symmetry using multiple generated class I plaster model

Sitter, Franziska 23 June 2016 (has links)
Einleitung: In der zahnärztlichen Literatur findet man klinische Studien, welche die Modifikation der sagittalen Kompensationskurve (SKK) aufgrund ihrer Entstehung, ihres Verhaltens während des Wachstums oder in Abhängigkeit von anderen Faktoren untersuchen. Zahlreichen Veränderungen und Variationen der SKK während des Zahnwechsels bzw. im Laufe des Lebens unterliegen dem Einfluss von Wachstum, kraniofazialer Morphologie, Kaukraft, Frontzahnmorphologie, Ausprägung der Okklusion und der relativen Lage der Kiefergelenke zur Mandibula sowie von weiteren Faktoren. Ziel: Das Ziel dieser Studie war eine Untersuchung der Variation der SKK in erneut aufgestellten Gipsmodellen von Doktorandin (D) und Studenten (S) in Neutralverzahnung. Im Rahmen der Überlegungen zur Biomechanik erhob sich die Frage, ob und gegebenenfalls wie sich die Ausprägung der SKK bei wiederholter Aufstellung in Neutralverzahnung trotz identischer Anatomie der Zähne verändert. Nach Überlegungen zur Okklusion und Morphologie ist bei der Verwendung von identischen Zähnen und idealer Aufstellung in Neutralverzahnung theoretisch nur eine Variante der Zahnbogenform und somit der SKK möglich. Es sollte untersucht werden, ob die Ausprägung der Kurve mit anderen Elementen wie Länge, Breite und Symmetrie des Zahnbogens korreliert. Es sollten Durchschnittstiefe beider Kieferseiten, die Position der tiefsten Stelle sowie Minimal- und Maximalwerte der SKK ermittelt werden. Modelle der Doktorandin (D) und Studenten (S) sollten verglichen werden. Material und Methoden: Das Ober- und Unterkiefer-Gipsmodell eines ausgesuchten Patientenfalls (Urmodell, Abschlussmodell nach kieferorthopädischer Behandlung, Neutralverzahnung) wurde 65-mal dubliert und die Zähne vom Zahnkranz separiert, so dass ein Puzzle der Okklusion erneut erstellt werden musste. Die Doktorandin stellte 20 Modelle und 45 Studenten jeweils ein Modell in Neutralverzahnung auf. Von den 65 so entstandenen Modellen wurden 58 ausgewertet. Vermessen wurden die Ausprägung der SKK, Zahnbogenbreite, Zahnbogenlänge sowie Symmetrie des Zahnbogens anhand Messschieber, Millimeterfolie sowie einer individuellen Messapparatur. Zur statistischen Auswertung wurden Korrelationsberechnungen, Hypothesentests (T-Test/ Welch-Test) sowie Boxplotdiagramme zur grafischen Darstellung erstellt. Ergebnisse: Es wurde eine negative Korrelation (r= -0,61) der Zahnbogenbreite mit der Zahnbogenlänge ermittelt. Es bestanden keine weiteren Korrelationen der SKK mit den übrigen Messwerten größer als r =0,6 oder kleiner als r= -0,6. Die S-Modelle waren breiter aufgestellt als die D-Modelle. Die SKK der D-Modelle waren in beiden Quadranten deutlich tiefer. Die Gesamtheit aller Modelle wies im 4. Quadranten tiefere Kurven als im 3. Quadranten auf. Durchschnittlich wiesen alle Modelle einen kürzeren dritten Quadranten auf. Aus der Horizontalebene betrachtet, verlief der Zahnbogen im vierten Quadranten steiler. Der tiefste Punkt der SKK ist der mesio-bukkale Höcker des ersten Molaren beidseits. Schlussfolgerung: Es konnte keine signifikante Abhängigkeit der Ausprägung der SKK von übrigen Messgrößen nachgewiesen werden. Betrachtet man die erstellten Modelle einzeln, so entstanden unterschiedlichste Ausprägungen der SKK, Zahnbogenbreiten und –längen bei funktioneller Okklusion. Die Mittelwerte aller vermessenen Modelle (Zahnbogenbreite und –länge) sind fast identisch mit denen des Urmodells ( 1,0mm). Das bestätigt zum Teil die Theorie, dass die Zahnbogenform durch die Zahnform vorgegeben ist. Die Mittelwerte schwanken um die Morphologie des Urmodells. Das Spiel für die Anordnung der Morphologie und Streubreite der Zahnbogenform ist größer als vorerst vermutet. Es müssen weitere Studien auf diesem Gebiet erfolgen, um den Sachverhalt genau zu prüfen. Als ein Ziel der kieferorthopädischen Behandlung wird das Abflachen einer ausgeprägten SKK empfohlen, um eine Neutralverzahnung weitestgehend einzustellen. Der Behandler sollte ausreichende Kenntnis über den idealen Verlauf der SKK besitzen, damit beim Gebrauch von starren Bögen während der terminalen Behandlung mit Straight-Wire-Technik eine Neutralverzahnung im Molarbereich gewährleistet bleibt.

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