Facial Convexity Angle Research Articles

Advancement Genioplasty––Cephalometric Analysis of Osseous and Soft Tissue Changes

Genioplasty is often performed to esthetically improve patient's profiles in the lower facial third. Many factors account for the variability in soft tissue response like dissection technique, magnitude and direction of movement and stability of the genial segment. Optimum treatment planning thus requires an understanding of the soft tissue response to various genial procedures. To determine the stability, ratio of hard and soft tissues and changes in the lower facial profile after advancement genioplasty. Ten patients were evaluated cephalometrically for the soft tissue changes in relation to hard tissues after advancement genioplasty. Pre operative, immediate post operative and 6months post operative lateral cephalogram were taken. Pre operative tracings were superimposed with post operative cephalograms to produce a composite tracing. Changes in the osseous tissues are assessed and related to the net changes in the soft tissues. The ratio of horizontal changes of osseous to soft tissues was found to be 1:0.89. The mean resorption was 0.85mm (10.7%). The vertical changes are minimal and non significant. There are significant changes in the soft tissue profile such as decrease in the soft tissue thickness, facial convexity angle, lower facial submental angle and increase in mentolabial sulcus depth. The standard advancement genioplasty procedure by inferior osteotomy of the chin with broadest musculo-periosteal pedicle with rigid internal fixation was followed. The soft tissue response is almost equal to the bony movement. The stability of the hard tissues is good with minimum amount of resorption so as to achieve more predictable results.

Common Standards in Facial Esthetics: Craniofacial Analysis of Most Attractive Black and White Subjects According to People Magazine During Previous 10 Years

The aim of the present case-control study was to determine--using the 10 most recent annual listings of the most beautiful black and white people--whether any common, measurable esthetic parameter could be extracted from both groups. A total of 80 women (40 white and 40 black), who had been included in the list of People magazine's 100 most beautiful people during the previous 10 years, were selected. Lateral photographs of all 80 subjects were obtained from Internet databases, oriented, and sized. A modified photogrammetric analysis was performed on the lateral view of each subject to obtain the angle and proportion measurements. Differences between the 2 groups were compared with 95% significance using the Student t test for independent samples. Facial similarities in the 2 ethnic groups were observed for the angle of the inferior facial third, labiomental angle, angle of facial convexity, and cervicomental angle. These results point to a similar conformation of the lower part of the face in relation to the neck that was shared by both groups of beautiful women. Additionally, both groups showed similar results for the lower lip projection. Likewise, similar proportional measurements were found for the upper lip proportion, notwithstanding differences in protrusion. Modern society is changing the classic concept of facial beauty because of globalization and the prevalence of multiethnic communities in the developed world. Independently of ethnic origin, beautiful women tend to have similar facial features that are a mixture of both black and white features.

Soft Tissue Profiles of 3-5 Year Old Preschool Children

Identifying the characteristics of soft-tissue profiles in 3-5 year old children. Children that participated in the study were selected from the 6 major districts of Ankara. In the selected schools, 3-5 year old 1513 children with primary dentition were examined and profile photographs were obtained. Facial convexity angle (FCA) and Total facial convexity angle (TFCA) were measured from profile photographs. The mean values for the total facial convexity (145.9 degrees +/- 4.2) and facial convexity (165.3 degrees +/- 4.5) angles were determined. FCA and TFCA were significantly influenced by primary second molar terminal plane relationship. Finding of this study may be used as clinical references for pediatric dental patients and also, the significant relationship between soft tissue profile and primary occlusion is important for orthodontic diagnosis and treatment of pediatric dental patients.

Avaliação dos fatores determinantes da estética do perfil facial

OBJETIVO: avaliar a influência da idade, do sexo, da relação oclusal sagital, do Padrão Facial e de 8 medidas do perfil facial sobre a estética do perfil. MÉTODOS: foram utilizadas tabelas de contingência, o Teste Qui-quadrado e o coeficiente de Cramér para avaliar a possível associação entre a nota dada por 32 avaliadores (14 ortodontistas, 12 leigos e 6 artistas) para a estética do perfil de 100 brasileiros - adultos, leucodermas, portadores de selamento labial passivo - e a idade, o sexo, a relação oclusal sagital, o Padrão Facial e as variáveis da análise facial numérica do perfil. RESULTADOS: não foi observada associação entre a idade, o sexo e a relação oclusal sagital e a estética do perfil facial. A associação foi observada entre a nota recebida para a estética do perfil e o Padrão Facial, o ângulo de convexidade facial e o ângulo do terço inferior da face. CONCLUSÃO: o Padrão Facial, definido na avaliação do perfil pela convexidade do perfil facial, e a projeção anterior do mento foram, entre os fatores avaliados, os determinantes para a estética do perfil facial.

Estudo das características cefalométricas em adolescentes brasileiros portadores de Padrão Face Longa

OBJETIVO: definir valores cefalométricos esqueléticos e dentários para adolescentes brasileiros com Padrão Face Longa. MÉTODOS: a amostra foi constituída de telerradiografias em norma lateral de 30 pacientes com Face Longa, sendo 17 do sexo feminino e 13 do masculino; e 30 pacientes face Padrão I, 15 do sexo masculino e 15 do feminino, no estágio de dentadura permanente durante a adolescência. As características do Padrão Face Longa foram definidas clinicamente, pela análise facial. As seguintes grandezas cefalométricas foram avaliadas: (1) Comportamento sagital das bases apicais (SNA, SNB, ANB, NAP, Co-A, Co-Gn); (2) Comportamento vertical das bases apicais (SN.PP, SN.PM, ângulo goníaco, AFAT, AFAI, AFAM, AFP, AFATperp, AFAIperp); (3) Comportamento dentoalveolar (1-PP, 6-PP, 1-PM, 6-PM, 1.PP, IMPA); e (4) Proporção entre as alturas faciais (AFAIPerp/AFATPerp, AFAI/AFAT, AFAM/AFAI). RESULTADOS E CONCLUSÕES: o erro vertical na Face Longa concentra-se no terço inferior. A maxila apresenta uma maior altura dentoalveolar e a mandíbula, com morfologia mais vertical, mostra maior rotação no sentido horário. Essas características morfológicas e espaciais acarretam alterações sagitais e verticais no esqueleto e alterações verticais dentoalveolares. No sentido sagital, os ângulos de convexidade facial estão aumentados. No sentido vertical, as alturas faciais anteriores total e inferior estão aumentadas. O componente dentoalveolar está mais longo.

Facial Anthropometric Analysis of the Javanese Female

Facial Anthropometric Analysis of the Javanese Female

Crescimento facial espontâneo Padrão II: estudo cefalométrico longitudinal

OBJETIVO: o presente estudo cefalométrico longitudinal investigou as alterações espontâneas ocorridas em crianças com má oclusão Classe II, divisão 1, Padrão II. MÉTODOS: foram selecionadas 40 crianças, 20 meninos e 20 meninas, distribuídas na faixa etária compreendida entre 6 e 14 anos de idade. Para avaliar o comportamento das bases apicais, dos incisivos e do tecido mole, as seguintes grandezas cefalométricas foram mensuradas: SN.Ba, SNA, SNB, SND, SN.Pog, ANB, NAP, SN.PP, SN.GoGn, SN.Gn, Ar.Go.Gn, 1.PP, 1.NA, 1.SN, IMPA e ANL. As seguintes grandezas alcançaram significância estatística com o crescimento: SNB, SND,SN.Pog,ANB,NAP,SN.GoGn,SN.Gn,Ar.Go.Gn e IMPA. RESULTADOS: os resultados demonstraram que as principais alterações quantitativas registradas estavam relacionadas com o crescimento mandibular,independentemente do gênero. A mandíbula deslocou-se para frente, com tendência de rotação no sentido anti-horário e com conseqüente redução nos ângulos de convexidade facial. No entanto, as oscilações quantitativas nas grandezas cefalométricas não foram suficientes para mudar a morfologia dentofacial ao longo do período de acompanhamento. CONCLUSÃO: conclui-se, portanto, que a morfologia facial é definida precocemente e é mantida, configurando o determinismo genético na determinação do arcabouço esquelético.

Anteroposterior Position of Mandible and Perceived Need for Orthognathic Surgery

This study investigated the association between the anteroposterior position of the mandible and the perceived need for orthognathic surgery. Profiles of 2 men, 1 black and 1 white, and 2 women, 1 black and 1 white, were photographed and altered to produce photos with a straight profile and 6 simulations of mandibular discrepancies, 3 by retrusion and 3 by protusion from each original face. The 28 faces were evaluated by orthodontists, maxillofacial surgeons, artists, and laypersons. The greatest numbers of indications for surgery were made for male convex profiles and for female concave profiles. Laypersons were more tolerant to profile changes, whereas maxillofacial surgeons indicated surgery and stated that they would seek facial surgery if profiles were their own in a greater number of cases. The angle of facial convexity has a strong effect on the perceived need for orthognathic surgery.

Angular photogrammetric analysis of the soft tissue facial profile of Turkish adults

One of the most important components of orthodontic diagnosis and treatment planning is the evaluation of the patient's soft tissue profile. The aim of this study was to develop angular photogrammetric standards for Class I Anatolian Turkish males and females. A random sample of 100 Turkish individuals (46 males and 54 females; ages 19-25 years) was obtained. The photographic set-up consisted of a tripod that held a 35 mm camera and a primary flash. The camera was used in its manual position and photographic records were taken of the subjects in natural head posture. The photographic records, 35 mm slide format, were digitized and analyzed using the Quick Ceph Image software program for Windows. Twelve measurements were digitally analyzed on each photograph. For statistical evaluation a Student's t-test was performed and the reliability of the method was analyzed. The results were compared with reported norms of facial aesthetics. The nasofrontal (G-N-Prn), nasal (Cm-Sn/N-Prn), vertical nasal (N-Prn/TV), and nasal dorsum (N-Mn-Prn) angles showed statistically insignificant gender differences (P>0.05). The nasolabial angle (Cm-Sn-Ls) demonstrated large variability. Gender differences were present in the mentolabial (Li-Sm-Pg) and cervicomental (G-Pg/C-Me) angles. The mentolabial angle showed a high method error and large variability. Facial (G-Sn-Pg) and total facial (G-Prn-Pg) convexity angles were similar, while Cm-Sn-Ls angle range was larger compared with other angles. The mean values obtained from this sample can be used for comparison with records of subjects with the same characteristics and following the same photogrammetric technique. Angular photogrammetric profile analysis can provide the orthodontist with a way of determining problems associated with various soft tissue segments of the face.

Soft and hard tissue changes after bimaxillary surgery in Turkish female Class III patients

Treatment of severe Class III malocclusion frequently requires a combination of orthodontics and orthognathic surgical procedures. The aims of this retrospective study were to assess the results of bimaxillary surgery on Turkish female subjects presenting with Class III malocclusions and to evaluate the correlation between soft and hard tissue changes. The sample consisted of 44 Turkish female Class III patients (mean age was 28.3+/-3.7 years) treated with bilateral sagittal split osteotomy and Le Fort I advancement with maxillary impaction. Lateral cephalograms were taken immediately before and 2.6+/-0.7 years after bimaxillary surgery. Paired t-test, Pearson correlation test and linear regression analysis procedures were used to assess the degree of correlation in terms of soft to hard tissue changes between the two cephalograms. All subjects presented with a presurgical concave profile. Maxillary advancement and impaction combined with mandibular setback surgery corrected the facial concavity and the improvement of horizontal and vertical positions. The lengths of the upper and lower lips and the horizontal position of the soft tissue pogonion were improved. The decrease in facial convexity angle was correlated with the increases in SNA angle and N-A distance. The significant increase in labiomental fold depth was significantly correlated with the significant decreases in N-ANS and ANS-Gn distances. The protrusion of the upper lip was correlated with the increases in SNA angle and N-A distance and also with the decrease in SNB angle. The retrusion of the lower lip was correlated with the decrease in N-B distance. The decrease in Sn to A distance was correlated with the increases in SNA, ANB and NAPg angles and N-A distance and also with the decrease in ANS-Gn distance. The increase in Pg' to Pg distance was correlated with the increases in SNA, ANB, NAPg angles and N-A distance. The increase in Si to B distance was correlated with the increases in SNA angle and N-A distance and also with the decreases in N-ANS and ANS-Gn distances. The decrease in Ls to U1 distance was correlated with the increases in SNA and ANB angles and with the increase in N-A distance and with the decreases in N-B and N-Pg distances. The decrease in Li to L1 distance was correlated with the increase in N-A distance. The elongation of the upper lip was correlated with the decrease in ANS-Gn distance. The increase in nasolabial angle was correlated with the decrease in ANS-Gn distance. Maxillary and mandibular soft and hard tissue movements showed significant correlations in horizontal and vertical directions 2.6+/-0.7 years after bimaxillary surgery.

Editor's Summary, Q & A, Reviewer's Critique: Evaluation of anterior open-bite treatment with occlusal adjustment

Introduction The purpose of this study was to evaluate the cephalometric and occlusal changes, the functional occlusion, and the dentinal sensitivity of anterior open-bite treatment with occlusal adjustment. Methods The sample comprised 20 patients who experienced relapse of the anterior open bite (mean, –1.06 mm). Occlusal adjustment was performed until a positive overbite was established. Cephalometric changes were evaluated on lateral cephalograms taken before and after the occlusal adjustment. The functional occlusion analysis consisted of evaluating immediate anterior and canine guidance and the number of teeth in contact before and after the procedure. Dentinal sensitivity was evaluated before, shortly after, and 4.61 months after the occlusal adjustment. Pretreatment and posttreatment cephalometric changes and the number of teeth in contact were compared with dependent t tests. Percentages of anterior and canine guidance before and after the adjustment procedure were compared with the McNemar test. To compare dentinal sensitivity at several stages, the nonparametric Friedman test was used, followed by the Wilcoxon test. Results Significant increases in overbite and mandibular protrusion were seen, as were significant decreases in apical base discrepancy, facial convexity, and growth pattern angles. The percentages of immediate anterior and canine guidance increased significantly, as did the number of teeth with occlusal contacts. Dentinal sensitivity increased immediately after the adjustment but decreased to normal levels after 4.61 months. Conclusions Occlusal adjustment is a viable treatment alternative for some open-bite patients; it establishes positive vertical overbite and improves the functional occlusion with only transient dentinal sensitivity. The purpose of this study was to evaluate the cephalometric and occlusal changes, the functional occlusion, and the dentinal sensitivity of anterior open-bite treatment with occlusal adjustment. The sample comprised 20 patients who experienced relapse of the anterior open bite (mean, –1.06 mm). Occlusal adjustment was performed until a positive overbite was established. Cephalometric changes were evaluated on lateral cephalograms taken before and after the occlusal adjustment. The functional occlusion analysis consisted of evaluating immediate anterior and canine guidance and the number of teeth in contact before and after the procedure. Dentinal sensitivity was evaluated before, shortly after, and 4.61 months after the occlusal adjustment. Pretreatment and posttreatment cephalometric changes and the number of teeth in contact were compared with dependent t tests. Percentages of anterior and canine guidance before and after the adjustment procedure were compared with the McNemar test. To compare dentinal sensitivity at several stages, the nonparametric Friedman test was used, followed by the Wilcoxon test. Significant increases in overbite and mandibular protrusion were seen, as were significant decreases in apical base discrepancy, facial convexity, and growth pattern angles. The percentages of immediate anterior and canine guidance increased significantly, as did the number of teeth with occlusal contacts. Dentinal sensitivity increased immediately after the adjustment but decreased to normal levels after 4.61 months. Occlusal adjustment is a viable treatment alternative for some open-bite patients; it establishes positive vertical overbite and improves the functional occlusion with only transient dentinal sensitivity.

Treatment effects of mini-implants for en-masse retraction of anterior teeth in bialveolar dental protrusion patients: A randomized controlled trial

The purpose of this randomized controlled trial was to quantify the treatment effects of en-masse retraction of anterior teeth with mini-implants as anchor units in bialveolar dental protrusion patients undergoing extraction of all 4 first premolars. A total of 40 patients (mean age, 17.5 years; SD, 3.2 years) were randomly assigned either to group 1 (G1), anterior space closure with mini-implants as anchor units, or group 2 (G2), anterior space closure with conventional methods of anchorage (without mini-implants). Skeletal, dental, and soft-tissue changes were analyzed in both groups on lateral cephalograms taken before retraction and after space closure. Student paired and unpaired t tests were used to analyze the treatment changes in the 2 groups. For the skeletal parameters, a statistically significant decrease in the facial vertical dimensions was seen in G1, but the variables in G2 showed no significant differences (P >0.05). Anchorage loss, in both the horizontal and vertical directions, was noted in G2, whereas G1 showed distalization (anchorage gain) and intrusion of molars. Although the soft-tissue response was variable, facial convexity angle, nasolabial angle, and lower lip protrusion had greater changes in G1. No differences were found in the amount of upper lip retraction between the groups (P >0.05). Mini-implants provided absolute anchorage to allow greater skeletal, dental, and esthetic changes in patients requiring maximum anterior retraction, when compared with other conventional methods of space closure. The treatment changes were favorable. However, no differences in the mean retraction time were noted between the 2 groups.

Evaluation of anterior open-bite treatment with occlusal adjustment

<b>Introduction:</b> The purpose of this study was to evaluate the cephalometric and occlusal changes, the functional occlusion, and the dentinal sensitivity of anterior open-bite treatment with occlusal adjustment. <b>Methods:</b> The sample comprised 20 patients who experienced relapse of the anterior open bite (mean, –1.06 mm). Occlusal adjustment was performed until a positive overbite was established. Cephalometric changes were evaluated on lateral cephalograms taken before and after the occlusal adjustment. The functional occlusion analysis consisted of evaluating immediate anterior and canine guidance and the number of teeth in contact before and after the procedure. Dentinal sensitivity was evaluated before, shortly after, and 4.61 months after the occlusal adjustment. Pretreatment and posttreatment cephalometric changes and the number of teeth in contact were compared with dependent <i>t</i> tests. Percentages of anterior and canine guidance before and after the adjustment procedure were compared with the McNemar test. To compare dentinal sensitivity at several stages, the nonparametric Friedman test was used, followed by the Wilcoxon test. <b>Results:</b> Significant increases in overbite and mandibular protrusion were seen, as were significant decreases in apical base discrepancy, facial convexity, and growth pattern angles. The percentages of immediate anterior and canine guidance increased significantly, as did the number of teeth with occlusal contacts. Dentinal sensitivity increased immediately after the adjustment but decreased to normal levels after 4.61 months. <b>Conclusions:</b> Occlusal adjustment is a viable treatment alternative for some open-bite patients; it establishes positive vertical overbite and improves the functional occlusion with only transient dentinal sensitivity.

Five year follow‐up of mandibular distraction osteogenesis on the dentofacial structures of syndromic children

To determine long-term treatment outcomes of mandibular distraction osteogenesis (DO) in syndromic children with severely hypoplastic lower jaws. Descriptive clinical study. Cleft Palate and Craniofacial Centre, Department of Plastic Surgery, Helsinki University Central Hospital. Ten children (mean age 7.6 years) with various syndromes (craniofacial microsomia, Treacher Collins syndrome, Nager syndrome). Ten growing children with severely retrognathic lower jaws were distracted with an extraoral bicortically fixed DO device (mean, 34 days) followed by a consolidation period (mean, 9 weeks). Orthodontic treatment was performed pre- and/or postoperatively with fixed or functional appliances (mean 14 months). The landmarks on standard lateral cephalometric X-rays were digitized and angular and linear measurements were compared using Student's t-test to assess changes in pre-distraction, post-distraction, post-consolidation and 1 year follow-up. Long-term follow-up (2 and 5 years) was interpreted according to mean values. The measurements of SNB, ANB, facial convexity angle, overjet and overbite, and soft tissue facial profile showed significant correction of the mandibular retrognathia and malocclusion. The mandibular divergence decreased and mandibular, corpus, and ramus lengths remained stable during the consolidation period. The regression of mandibular measurements towards pre-distraction values was observed in skeletal and dental parameters and soft tissue profiles during the first postoperative year and continued during the 2- to 5-year follow-up period. The achieved mandibular corpus and ramus lengthening was stable while the mandible displayed considerable posterior rotation but no further growth. Orthodontic treatment could not overcome the regression of mandibular measurements to their original values. The maxilla continued its normal growth during the long-term follow-up. Two patients had tracheostomies, but the tube was removed from both during or immediately after distraction. CONCLUSION - Excellent short-term structural results of mandibular DO are not stable during the growth of syndromic children because of restricted mandibular growth. Thus, a re-evaluation of DO timing in the improvement of facial aesthetics must be considered. However, mandibular DO in children with severe airway problems is recommended.

Soft-tissue cephalometric norms in Yemeni men

The main purpose of this study was to develop soft-tissue cephalometric standards for Yemeni men and compare them with the cephalometric standards of normal North American white people. Fifty Yemeni men (ages, 20-27 years; mean, 23.1 years) with normal occlusion were selected. With double selection by orthodontists and laypersons, a subsample of esthetically pleasing subjects was selected. Lateral cephalometric radiographs of all subjects were analyzed according to the Legan-Burstone and the Holdaway analyses. The Yemeni esthetically pleasing subjects (YPG) and the remaining subjects (YNG) showed significant differences with respect to mandibular prognathism, lower face-throat angle, nasolabial angle, mentolabial sulcus depth, and interlabial gap, when compared with the Legan-Burstone norms for white Americans; the YPG also had significantly less obtuse facial convexity angle than the YNG. Most values of both Yemeni groups were generally within the range of the values reported by Holdaway, except for 3 variables: skeletal profile convexity, basic upper-lip thickness, and H-angle, which were all significantly larger than those of Holdaway; the YPG showed less skeletal profile convexity than the YNG. These results show that the soft-tissue facial profiles of white Yemenis and Americans are different in certain respects; these racial differences must be considered during diagnosis and treatment planning. These results should serve as a useful reference for orthodontists and maxillofacial surgeons who treat Yemeni patients and also contribute to more satisfactory diagnosis and treatment planning for them.

Computer Imaging Software for Profile Photograph Analysis

To describe a novel calibration technique for photographs of different sizes and to test a new method of chin evaluation in relation to established analysis measurements. A photograph analysis and medical record review of 14 patients who underwent combined rhinoplasty and chin correction at an academic center. Patients undergoing concurrent orthognathic surgery, rhytidectomy, or submental liposuction were excluded. Preoperative and postoperative digital photographs were analyzed using computer imaging software with a new method, the soft tissue porion to pogonion distance, and with established measurements, including the cervicomental angle, the mentocervical angle, and the facial convexity angle. The porion to pogonion distance consistently increased after the chin correction procedure (more in the osseous group). All photograph angle measurements changed toward the established normal range postoperatively. Surgery for facial disharmony requires artistic judgment and objective evaluation. Although 3-dimensional video analysis of the face seems promising, its clinical use is limited by cost. For surgeons who use computer imaging software, analysis of profile photographs is the most valuable tool. Even when preoperative and postoperative photographs are of different sizes, relative distance comparisons are possible with a new calibration technique using the constant facial landmarks, the porion and the pupil. The porion-pogonion distance is a simple reproducible measurement that can be used along with established soft tissue measurements as a guide for profile facial analysis.

Análise facial numérica do perfil de brasileiros Padrão I

OBJETIVO: o objetivo do presente estudo foi determinar as medidas do perfil facial de brasileiros portadores de equilíbrio facial, denominados Padrão I. METODOLOGIA: a amostra foi constituída por 50 indivíduos (32 femininos e 18 masculinos), brasileiros, adultos, leucodermas, com idade média de 23 anos. Fotografias padronizadas do perfil foram obtidas. Sobre essas foram executados os traçados por dois avaliadores, que verificaram: 1) ângulo nasolabial; 2) ângulo mentolabial; 3) ângulo interlabial; 4) ângulo de convexidade facial; 5) ângulo de convexidade facial total; 6) ângulo do terço inferior da face; 7) proporção entre a altura facial anterior média e a altura facial anterior inferior e 8) proporção do terço inferior da face. RESULTADOS E CONCLUSÕES: não houve diferença estatística relevante entre as duas medidas realizadas. Os valores de média, desvio-padrão, valores máximos e mínimos obtidos para cada variável estudada foram: 1) ângulo nasolabial: 108,13° ± 9,75° (81° a 127°); 2) ângulo do sulco mentolabial: 132,37° ± 9,82° (110,5° a 152°); 3) ângulo interlabial: 135,35° ± 11,14° (116,5° a 159,5°); 4) ângulo de convexidade facial: 12,32°± 3,93° (4° a 19,5°); 5) ângulo de convexidade facial total: 137,85° ± 4,08° (129,5° a 147,5°); 6) ângulo do terço inferior da face: 103,41° ± 8,12° (88° a 124°); 7) proporção entre os terços médio e inferior da face: 0,93 ± 0,10 (0,80 a 1,21) e 8) proporção do terço inferior da face: 0,45 ± 0,06 (0,30 a 0,67). Propõe-se esse conjunto de medidas como um padrão de referência para avaliação facial numérica de adultos, brasileiros, brancos.

Anquilose intencional dos caninos decíduos como reforço de ancoragem para a tração reversa da maxila: estudo cefalométrico prospectivo

OBJETIVO: o presente trabalho de pesquisa analisou os efeitos da tração reversa da maxila associada à anquilose intencional dos caninos decíduos superiores, mediante o emprego da cefalometria. METODOLOGIA: o protocolo de tratamento incluiu: 1) anquilose intencional dos caninos decíduos superiores; 2) expansão rápida da maxila e 3) tração reversa da maxila, imediatamente após o término da fase ativa da expansão. A amostra foi composta de 18 crianças nos estágios de dentadura decídua e dentadura mista, com idade média inicial de 7 anos e 1 mês. O intervalo médio de tratamento com a tração reversa da maxila foi de 1 ano e 1 mês. As telerradiografias laterais foram obtidas na documentação inicial e após a correção da Classe III. RESULTADOS E CONCLUSÕES: os resultados demonstram que os ângulos representativos da convexidade facial, NAP e ANB, aumentaram de 0º para 6,6º e 3,5º, respectivamente. Isso significa dizer que a face transformou-se de reta ou côncava, peculiar na Classe III, para uma face convexa, característica de normalidade no estágio avaliado. Essa melhora na convexidade facial é atribuída ao avanço da maxila, registrado tanto na região alveolar (ângulo SNA e as distâncias Co-A e NPerp-A) como na região basal (ângulo SN.ENA). A maxila deslocou-se para frente, enquanto a redução do ângulo SNB de 80,56º para 79,61º demonstrou um retroposicionamento mandibular. Além da mudança no sentido sagital, houve rotação da mandíbula no sentido horário, com aumento dos ângulos SN.GoGn e SN.Gn. Somado aos efeitos ortopédicos, houve inclinação vestibular dos incisivos superiores.

Distraction Osteogenesis in Adolescents with Maxillary Arch Deficiency and Dental Crowding: A 3-Year Follow-Up

In this study, the authors evaluated the long-term results after using anterior segmental osteotomy and distraction osteogenesis for the correction of sagittal maxillary deficiency associated with dental crowding. Six young adolescents (four boys and two girls) underwent surgery and distraction at a mean age of 11.2 years (range, 10 to 12 years) and were followed up for 3 years. A tooth-borne distraction device was used for interdental distraction. The evaluation consisted of hard- and soft-tissue profile analysis and dental arch measurements before, immediately after, and 3 years after distraction. The results showed that the facial profile, the occlusion, and the dental crowding could be successfully corrected and that the results were stable after 3 years' follow-up. The mean facial convexity angle was changed from 1 to 8 degrees. The average advancement at point A was 4 mm and the SNA increased by an average of 4 degrees. Lengthening of the dental arch by an average of 4 mm created approximately 8 mm of new space, sufficient to resolve the dental crowding in all patients, thus avoiding an extraction of healthy teeth. The results of this study demonstrated that anterior segmental maxillary osteotomy combined with distraction osteogenesis offers an alternative for the treatment of adolescents suffering from sagittal maxillary deficiency with dental crowding.

Determinants of successful chincup therapy in skeletal class III malocclusion

The purpose of this study was to investigate skeletal characteristics that determine successful chincup therapy in patients with skeletal Class III malocclusions by using longitudinal follow-up data of 40 patients (18 male, 22 female). Lateral cephalometric radiographs were taken before chincup therapy (T0), after chincup therapy (T1), and after fixed orthodontic treatment and retention (T2). From the measurements at T2, the patients were classified into group 1, showing good retention results (n = 21; 9 male, 12 female), or group 2, showing poor results (n = 19; 9 male, 10 female). The differences at each stage and during T0 to T1 and T1 to T2 between the 2 groups were compared by t tests. The major effect of chincup therapy was backward rotation of the mandible in both groups; however, the amount of rotation was greater in group 2. After retention, group 2 showed more forward rotation and forward growth of the mandible than group 1. Cephalometric measurements that showed significant differences in skeletal and dental morphology between the 2 groups at T0 were L1 to occlusal plane ( P < .001), upper gonial angle, AB to occlusal plane angle, AB to mandibular plane angle, ANB, anteroposterior dysplasia indicator, Wits appraisal ( P < .01), articular angle, gonial angle, facial convexity angle, AB to facial plane angle, and L1 to A-Pog ( P < .05). These factors apparently contributed to the difference of long-term results in the 2 groups. It is necessary to evaluate these items in the diagnosis and treatment planning of skeletal Class III malocclusion in growing patients when chincup therapy is being considered.