RESUMO
INTRODUCTION: This study was designed to evaluate the long-term prevalence of gingival recession after orthodontic tooth movements, focusing on the effects of mandibular incisor proclination and expansion of maxillary posterior teeth. METHODS: Records of 205 patients (162 female, 43 male) were obtained from 2 private practice orthodontists. Using pretreatment (age, 14.0 ± 5.9 years) and posttreatment (age, 16.5 ± 6.0 years) lateral cephalograms and dental models, mandibular incisor proclination and maxillary arch widths were measured. Gingival recession was measured based on posttreatment and postretention (age, 32.3 ± 8.5 years) intraoral photographs and models. Associations between tooth movements and gingival recession were evaluated statistically. RESULTS: Only 5.8% of teeth exhibited recession at the end of orthodontic treatment (only 0.6% had recession >1 mm). After retention, 41.7% of the teeth showed recession, but the severity was limited (only 7.0% >1 mm). There was no relationship between mandibular incisor proclination during treatment and posttreatment gingival recession. Incisors that finished treatment angulated (IMPA) at 95° or greater did not show significantly more recession than did those that finished less than 95°. There were weak positive correlations (r = 0.17-0.41) between maxillary arch width increases during treatment and posttreatment recession. CONCLUSIONS: Orthodontic treatment is not a major risk factor for the development of gingival recession. Although greater amounts of maxillary expansion during treatment increase the risks of posttreatment recession, the effects are minimal.
Assuntos
Retração Gengival/etiologia , Técnicas de Movimentação Dentária/efeitos adversos , Adolescente , Adulto , Feminino , Retração Gengival/epidemiologia , Humanos , Masculino , Prevalência , Estudos RetrospectivosAssuntos
Ortodontia , História do Século XX , Humanos , Ortodontia/história , Ortodontia/métodos , Estados UnidosRESUMO
The aim of this study was to assess the impact of various sized buccal corridors (BCs) on smile attractiveness. One female smiling photograph, displaying first molar to first molar (M1-M1), was digitally altered to produce (1) smiles that filled 84, 88, 92, 96, and 100 per cent of the oral aperture; (2) second premolar to second premolar smiles (PM2-PM2) that filled 84, 88, 92, and 96 per cent of the oral aperture; and (3) smiles with asymmetrical BC that filled 88, 90, 94, and 96 per cent of the oral aperture. The 18 smiles produced were evaluated by 82 orthodontists (70 males and 12 females) and 94 laypeople (40 males and 54 females). Paired t-tests were used to evaluate differences within the orthodontist and laypeople groups: independent t-tests were used to compare the two groups. The effect of age and gender on the ratings was evaluated by two-way analysis of variance. Orthodontists and laypeople rated smiles with small BCs as significantly (P < 0.05) more attractive than those with large BCs. Orthodontists rated M1-M1 smiles as more attractive than PM2-PM2 smiles, whereas laypeople preferred PM2-PM2 smiles. Orthodontists rated only two of eight asymmetrical smiles as less attractive than would be expected for symmetrical smiles with similar arch widths; laypeople did not rate any asymmetrical smiles as less attractive than would be expected. Rater age and gender did not significantly influence the impact of BCs on smile attractiveness.
Assuntos
Estética Dentária/psicologia , Lábio/anatomia & histologia , Sorriso , Fatores Etários , Análise de Variância , Atitude do Pessoal de Saúde , Odontólogos/psicologia , Feminino , Humanos , Masculino , Ortodontia , Opinião Pública , Fatores SexuaisRESUMO
INTRODUCTION: The treatment effects and the short-term (0.9 +/- 0.45 years) relapse potential of phase I slow maxillary expansion, with a bonded palatal expander or a quad-helix appliance combined with a mandibular banded Crozat/lip bumper and followed by 12 to 15 months of retention, were examined. METHODS: Pretreatment (8.8 +/- 1.7 years) and posttreatment (11.1 +/- 1.7 years) models of 54 patients were used to evaluate treatment effects. Posttreatment (11.0 +/- 1.3 years) and follow-up (11.9 +/- 1.4 years) models of 23 patients who returned for phase II treatment were used to evaluate relapse over the 11 months, during which no retention was used. The models were digitized, and 15 measures were computed. RESULTS: Significant treatment increases were observed for all measurements in both arches. Treatment gains in arch perimeter (6%-8%) were due more to increases in intermolar width (11%-15%) than to increases in arch depth (5%). Posttreatment relapse was significant (P <.05) for all measures except mandibular intercanine width and maxillary molar arch depth. After accounting for normal growth, net changes (pretreatment to follow-up) indicated significant increases for all measures except maxillary molar arch depth. In addition to maintaining leeway space, the maxilla and the mandible showed net perimeter gains of 2.9 and 1.0 mm, respectively. CONCLUSIONS: Slow maxillary expansion combined with a mandibular banded Crozat/lip bumper during the early mixed dentition produced clinically useful increases in arch dimensions that subsequently underwent mild-to-moderate amounts of relapse after removal of all retention appliances.
Assuntos
Arco Dental/anatomia & histologia , Má Oclusão/terapia , Mandíbula/anatomia & histologia , Maxila/anatomia & histologia , Técnica de Expansão Palatina/instrumentação , Cefalometria , Criança , Dentição Mista , Feminino , Humanos , Masculino , Modelos Dentários , Recidiva , Reprodutibilidade dos Testes , Fatores de TempoRESUMO
INTRODUCTION: The purpose of this investigation was to determine the long-term differences in soft tissue profile changes between extraction and nonextraction patients who had been treated to the same incisor position and lip line. METHODS: Twenty extraction and 20 matched nonextraction patients, with posttreatment and long-term follow-up (average 15 years) records, were selected from a single private orthodontic practice. Posttreatment and long-term follow-up profile photos of the patients' nose, lip, and chin areas were evaluated by 105 orthodontists and 225 laypeople, who indicated their preferences and the amount of change they perceived among the 40 profiles. The patients had similar dental protrusion, soft tissue profile measurements, and ages at the posttreatment observation. RESULTS: No significant cephalometric differences between the extraction and nonextraction groups were found at long-term follow-up; both groups showed similar long-term changes. Significant (P < .05) differences were found between males and females at long-term follow-up; male lips became relatively more retrusive, and their profiles became flatter. Significant (P < .05) changes in the profiles were also perceived over time, but there was no relationship between the amount of change perceived and profile changes measured cephalometrically. There were also no significant (P < .05) differences in preferences between orthodontists and laypeople, between extraction and nonextraction patients, or between males and females. CONCLUSIONS: If extraction and nonextraction patients are treated to the same incisor position and lip line, the treatment modality does not affect long-term soft tissue profile changes. Furthermore, the amounts of change perceived by either orthodontists or laypeople were not related to the amount of change measured cephalometrically.
Assuntos
Estética Dentária , Face/anatomia & histologia , Má Oclusão/terapia , Ortodontia Corretiva/métodos , Extração Dentária , Dente Pré-Molar/cirurgia , Cefalometria , Feminino , Seguimentos , Humanos , Masculino , Análise por Pareamento , Desenvolvimento Maxilofacial , Ortodontia Corretiva/estatística & dados numéricos , Fatores Sexuais , Resultado do TratamentoRESUMO
INTRODUCTION: The purpose of this study was to evaluate the long-term postretention stability of rapid palatal expansion-lip bumper therapy followed by full fixed appliances. METHODS: The sample included 20 treated patients (11 women and 9 men) who were recalled to obtain postretention records. The subjects were out of retention for a minimum of 4 years and an average of 7.9 years. They had begun treatment in the late mixed dentition at a mean age of 11.1 with considerable incisor crowding but, on average, no tooth size-arch length discrepancies. Pretreatment, posttreatment (mean age, 13.6 years), and postretention (mean age, 24.3 years) models were digitized, and the computed measurements were compared with untreated reference data. RESULTS: The majority of treatment increases in maxillary and mandibular arch dimensions were statistically significant (P < .05) and greater than expected for untreated controls. Although many measurements decreased postretention, net gains were maintained for 21 of the 30 measurements evaluated. The notable exception was arch perimeter, which decreased to less than pretreatment values. Postretention incisor irregularity increased 0.5 +/- 1.2 mm in the maxillary arch and 1.1 +/- 1.5 mm in the mandibular arch. CONCLUSIONS: Based on the good long-term stability observed in this study, we concluded that use of rapid palatal expansion-lip bumper expansion therapy in the late mixed dentition followed by full fixed appliances is an effective form of treatment for patients with up to moderate tooth size-arch length discrepancies.
Assuntos
Aparelhos de Tração Extrabucal , Má Oclusão/terapia , Técnica de Expansão Palatina/instrumentação , Criança , Arco Dental/anatomia & histologia , Feminino , Humanos , Incisivo/fisiopatologia , Lábio , Masculino , Mandíbula , Odontometria , Aparelhos Ortodônticos , Contenções Ortodônticas , Recidiva , Reprodutibilidade dos Testes , Estudos Retrospectivos , Resultado do TratamentoRESUMO
This study evaluates Class I, 4-premolar-extraction patients who were treated with the edgewise appliance by 1 practitioner, according to the philosophy of Tweed, and who had been out of retention a minimum of 5 years. The sample includes 32 patients, who started treatment at an average age of 12.8 years and who were examined a mean of 15 years posttreatment (11.7 years postretention). Cephalometric and model analyses were conducted to evaluate treatment and posttreatment tooth movements. The results showed that irregularity, as measured by the irregularity index, decreased 5.3 mm during treatment and increased 0.7 mm (SD 1.1 mm) during the posttreatment period. Eighty percent of the patients had satisfactory (<3.5 mm) mandibular incisor alignment over 10 years postretention, and none was in the severe category (>6.5 mm). Mandibular intercanine width increased (1.7 mm) during treatment, whereas intermolar width decreased (-2.1 mm). Maxillary molar widths remained unchanged posttreatment, and mandibular intercanine width decreased 1.4 mm from immediately posttreatment to postretention. Arch lengths decreased during treatment because of molar protraction and incisor retraction. Mandibular arch length continued to decrease posttreatment (-1.4 mm) because of mesial molar movement rather than distal incisor movement. Satisfactory long-term results can be achieved for most Class I, 4-premolar-extraction patients for whom evidence-based treatment objectives-including minimal alteration of the mandibular arch form and the retraction and uprighting or maintenance of mandibular incisors in their original position-have been met.