Management of ankylosed teeth using the decoronation technique: integrative literature review and case report.

INTRODUCTION: The decoronation technique has been described in literature since 1984 and, based on the available results, it can lead to considerable benefits for the repair and rehabilitation of ankylosed teeth. Based on these reports, one could expect that this procedure would be well known by the dental community. However, this fact does not seem to be true, and this procedure is not widely used. METHODS: The objective of this paper is to present appropriate literature that discusses decoronation and evaluate the perspectives of the procedure, both in relation to the technique and the long-term benefits for the patient. An integrative literature review at PubMed, ScieELO, and Lilacs databases was performed using the keywords "decoronation", "ridge preservation decoronation", "decoronation ankylosis". In addition, a case report will be presented to demonstrate the technique in a systematic and detailed manner. RESULTS: Considering the inclusion criteria, 27 articles that present consistency regarding decoronation were selected. CONCLUSION: There is scarce availability of scientific works related to the topic, to corroborate and discuss the technique. The present paper reinforces the benefits of this procedure, and revisit decoronation, attempting to provide a possible treatment for ankylosed teeth in growing patients.

Evaluation of enamel thickness of mandibular incisors.

OBJECTIVE: To measure enamel thickness at the proximal surfaces of the mandibular incisors, using micro-computed tomography (micro-CT) scans. MATERIAL AND METHODS: Forty-one single-rooted mandibular incisors were selected and analyzed according to anatomical characteristics, to form three groups: Group 1 - central incisors (n = 18); Group 2 - right lateral incisors (n = 10); and Group 3 - left lateral incisors (n = 13). First, enamel thickness at the proximal contact areas of the mandibular incisors was measured. Second, the mesial and distal surfaces of the lateral incisors were compared. Finally, the relationship between the tooth width and the mean enamel thickness was determined. Each tooth was scanned with a micro-CT scanner, and the image was processed with SCANCO micro-CT onboard analysis software. RESULTS: There were no statistically significant differences in mean enamel thickness between the mesial and distal surfaces for each lateral incisor, or between contralateral lateral incisors. In all surfaces analyzed, the upper zones had statistically significantly thinner enamel (0.52 ± 0.10 mm) when compared to the middle and lower zones (0.60 ± 0.08 mm and 0.59 ± 0.08 mm, respectively). There was no correlation (r =0.07) between enamel thickness of the mandibular incisor and the tooth width. CONCLUSIONS: The enamel thickness of the mandibular incisors is similar on the mesial and distal surfaces, with the thinnest layer located at the upper zone.

The effect of maxillary first and mandibular second premolar extractions on the posterior Bolton ratio.

INTRODUCTION: The anterior and overall Bolton ratios and their application in orthodontics are widely known. However, little has been reported about the posterior Bolton ratio, how it is affected by the extraction of posterior teeth, and its application in orthodontic treatment planning. This study aimed to investigate how extracting maxillary first and mandibular second premolars affects the posterior Bolton ratio. METHODS: The sample included 55 patients with Class I occlusion within 1 standard deviation of ideal anterior and overall Bolton ratios. The digitized models were subjected to virtual extraction of maxillary first premolars and mandibular second premolars and setup of posterior teeth in ideal occlusion. If space closure compromised occlusion, the teeth were moved to achieve ideal cusp-fossa or cusp-marginal ridge occlusion. The ideal setups were measured for residual interproximal spacing. Statistical analysis used R statistical software (version 2018; R Core Team, Vienna, Austria). RESULTS: The ideal nonextraction posterior Bolton ratio was determined from the sample to be 105.77 ± 1.99%. The ideal expected posterior Bolton ratio for maxillary first and mandibular second premolar extraction patients was 106.52 ± 2.52%. This significantly differed from the expected posterior Bolton ratio for the 4 first premolar extractions. Patients finished with an average of 1.28 mm net residual spacing between mandibular first premolars and first molars; 38.2% of patients finished with at least 1.5 mm of residual space, and 9.1% of patients finished with at least 2 mm of residual space. CONCLUSIONS: A patient with ideal anterior, posterior, and overall Bolton ratios treated with maxillary first and mandibular second premolar extractions to ideal occlusion will likely finish with some spacing in the mandibular dentition.

Is there a better interceptive treatment for unerupted palatally displaced canines? A network meta-analysis.

This systematic review aimed to investigate if there is a better interceptive treatment for palatally displaced canines (PDC) in the mixed dentition stage. The PubMed/MEDLINE, CENTRAL, Scopus, and EMBASE databases were searched for randomized clinical trials related to the research topic. The gray literature and reference lists were also assessed. Network meta-analysis was conducted to analyze the effects of different approaches on PDC eruption. The surface under the cumulative ranking area was calculated to rank the treatments. The certainty of the evidence was evaluated using the GRADE approach. Of the 892 eligible studies, 18 were selected for full-text analysis and 9 for meta-analysis, involving 506 participants and 730 PDC, to compare 9 approaches. The proportion of erupted PDC was significantly higher for all interceptive treatments compared with control (no intervention). Furthermore, the proportion of erupted PDC was higher in patients subjected to rapid maxillary expansion (RME) than those who underwent double extraction of primary canine and primary molar (relative risk (RR) = 2.68 ICr95%: 1.12-9.35). A higher proportion of erupted PDC was found for RME (RR = 3.07 ICr95%: 1.31-10.67), RME plus use of transpalatal arch (TA) plus extraction of primary canine(s) (EC) (RR = 1.43 ICr95%: 1.09-1.95), EC plus use of cervical pull headgear (RR = 1.38 ICr95%: 1.11-1.79), and EC plus use of TA (RR = 1.36 ICr95%: 1.00-1.9) than for EC. RME was most likely to be considered as the best interceptive treatment. Overall, the certainty of the evidence was considered low due to imprecision and indirectness. In conclusion, no intervention in the mixed dentition stage is the worst choice for PDC.

Management of ankylosed teeth using the decoronation technique: integrative literature review and case report

ABSTRACT Introduction: The decoronation technique has been described in literature since 1984 and, based on the available results, it can lead to considerable benefits for the repair and rehabilitation of ankylosed teeth. Based on these reports, one could expect that this procedure would be well known by the dental community. However, this fact does not seem to be true, and this procedure is not widely used. Methods: The objective of this paper is to present appropriate literature that discusses decoronation and evaluate the perspectives of the procedure, both in relation to the technique and the long-term benefits for the patient. An integrative literature review at PubMed, ScieELO, and Lilacs databases was performed using the keywords "decoronation", "ridge preservation decoronation", "decoronation ankylosis". In addition, a case report will be presented to demonstrate the technique in a systematic and detailed manner. Results: Considering the inclusion criteria, 27 articles that present consistency regarding decoronation were selected. Conclusion: There is scarce availability of scientific works related to the topic, to corroborate and discuss the technique. The present paper reinforces the benefits of this procedure, and revisit decoronation, attempting to provide a possible treatment for ankylosed teeth in growing patients.

RESUMO Introdução: A técnica de decoronação é descrita na literatura desde 1984 e, com base nos resultados disponíveis, pode trazer benefícios consideráveis para o reparo e reabilitação de dentes anquilosados. Com base nesses relatos, seria esperado que esse procedimento fosse bem conhecido pela comunidade odontológica. No entanto, isto não parece ser verdadeiro e esse procedimento não é amplamente utilizado. Objetivo: O objetivo deste artigo é apresentar literatura adequada que discuta a decoronação e avalie as perspectivas do procedimento, tanto em relação à técnica quanto aos benefícios em longo prazo para o paciente. Métodos: Foi realizada revisão integrativa da literatura nas bases de dados PubMed, SciELO e Lilacs, utilizando as seguintes palavras-chave: "decoronation", "ridge preservation decoronation", "decoronation ankylosis". Além disso, um relato de caso demonstrará a técnica de maneira sistemática e detalhada. Resultados: Considerando os critérios de inclusão, foram selecionados 27 artigos que apresentam consistência quanto à decoronação. Conclusão: Há escassa disponibilidade de trabalhos científicos relacionados ao tema para corroborar e discutir a técnica. Esse artigo reforça os benefícios desse procedimento e revisa a decoronação na tentativa de fornecer um possível tratamento para dentes anquilosados em pacientes em crescimento.

Evaluation of enamel thickness of mandibular incisors

ABSTRACT Objective: To measure enamel thickness at the proximal surfaces of the mandibular incisors, using micro-computed tomography (micro-CT) scans. Material and Methods: Forty-one single-rooted mandibular incisors were selected and analyzed according to anatomical characteristics, to form three groups: Group 1 - central incisors (n = 18); Group 2 - right lateral incisors (n = 10); and Group 3 - left lateral incisors (n = 13). First, enamel thickness at the proximal contact areas of the mandibular incisors was measured. Second, the mesial and distal surfaces of the lateral incisors were compared. Finally, the relationship between the tooth width and the mean enamel thickness was determined. Each tooth was scanned with a micro-CT scanner, and the image was processed with SCANCO micro-CT onboard analysis software. Results: There were no statistically significant differences in mean enamel thickness between the mesial and distal surfaces for each lateral incisor, or between contralateral lateral incisors. In all surfaces analyzed, the upper zones had statistically significantly thinner enamel (0.52 ± 0.10 mm) when compared to the middle and lower zones (0.60 ± 0.08 mm and 0.59 ± 0.08 mm, respectively). There was no correlation (r =0.07) between enamel thickness of the mandibular incisor and the tooth width. Conclusions: The enamel thickness of the mandibular incisors is similar on the mesial and distal surfaces, with the thinnest layer located at the upper zone.

RESUMO Objetivo: Medir a espessura do esmalte nas superfícies proximais dos incisivos inferiores, usando imagens de microtomografia computadorizada (micro-CT). Material e Métodos: Quarenta e um incisivos inferiores com raiz única foram selecionados e analisados de acordo com as características anatômicas, formando três grupos: Grupo 1 - incisivos centrais (n = 18); Grupo 2 - incisivos laterais direitos (n = 10); e Grupo 3 - incisivos laterais esquerdos (n = 13). Primeiro, foi medida a espessura do esmalte nas áreas de contato proximal dos incisivos inferiores. Em segundo lugar, as faces mesial e distal dos incisivos laterais foram comparadas. Por fim, foi determinada a relação entre a largura do dente e a espessura média do esmalte. Cada dente foi escaneado com um scanner micro-CT, e a imagem foi processada com o software de análise SCANCO micro-CT. Resultados: Não houve diferenças estatisticamente significativas na espessura média do esmalte entre as superfícies mesial e distal de cada incisivo lateral, ou entre os incisivos laterais contralaterais. Em todas as superfícies analisadas, as zonas superiores apresentaram esmalte significativamente mais fino (0,52 ± 0,10 mm) quando comparadas às zonas média e inferior (0,60 ± 0,08 mm e 0,59 ± 0,08 mm, respectivamente). Não houve correlação (r = 0,07) entre a espessura do esmalte do incisivo inferior e a largura do dente. Conclusões: A espessura do esmalte dos incisivos inferiores é semelhante nas faces mesial e distal, com a camada mais fina localizada na zona superior.

Apicotomia ­ a última fronteira para o tracionamento do canino impactado anquilosado / Apicotomy ­ the last frontier for ankylosed impacted canine traction

Resumo O objetivo deste artigo é descrever o caso clínico com uma má oclusão Classe I de Angle com ambos os caninos superiores impactados e a biomecânica ortodôntico-cirúrgica para o posicionamento na linha de oclusão. Paciente do sexo masculino, com 16,7 anos de idade. No exame facial apresentou perfil reto tendendo ao côncavo, nariz e pogônio proeminentes. No exame dentário, má oclusão Classe I, overjet normal, overbite exagerado e a retenção prolongada dos caninos superiores decíduos que, segundo radiografia panorâmica e tomografia, estavam altos e retidos por palatino. Tal quadro estava associado à dilaceração do ápice radicular de ambos os caninos. Durante o progresso do tratamento, observou-se a anquilose do canino esquerdo e preconizou-se a apicotomia, que respondeu à movimentação até a linha de oclusão. O tratamento foi finalizado com overbite adequado com estética e manutenção da harmonia facial. A apicotomia foi eficaz como a última alternativa para o nivelamento. Os resultados de estética, função, saúde e estabilidade após a apicotomia foram obtidos e estão mantidos no follow-up de 10 anos. (AU)

Abstract The aim of this study was to describe an Angle Class I malocclusion with both impacted maxillary canines and orthodontic-surgical biomechanics for positioning in the line of occlusion. Male patient, 16.7 years old. The facial examination showed a straight profile tending to concave, prominent nose, and pogonion. On dental examination, Class I malocclusion, normal overjet, exaggerated overbite, prolonged presence of deciduous canines. Panoramic radiography and tomography revealed a high and palatal position, associated with laceration of the root apex of both canines. During the treatment progress, left canine ankylosis was observed. After the apicotomy, the canine responded to the movement up to the occlusion line and the treatment ended with an appropriate overbite with aesthetics and the maintenance of facial harmony. Apicotomy was effective as an alternative. The results of aesthetics, function, health, and stability after failure of conventional ortho-surgical traction were obtained and are maintained in the 10-year follow-up.(AU)

Dimensional and morphologic characteristics of unilateral impacted maxillary central incisors.

INTRODUCTION: This cross-sectional study aimed to investigate the crown and root characteristics of impacted central incisors compared with spontaneously erupted contralateral incisors and the influence of etiologic and local factors on their dimensions. METHODS: Forty-five patients (22 boys, 23 girls) who underwent orthodontic treatment for unilateral impaction of maxillary central incisors were referred for cone-beam imaging. Dimensions of the impacted and contralateral incisors were assessed using Dolphin 3D software (Dolphin Imaging & Management Solutions, Chatsworth, Calif). Paired t test and linear regression were used to compare the characteristics of the impacted and contralateral teeth. RESULTS: Contralateral and impacted central incisors showed statistically significant differences for root length (95% confidence interval [CI], 2.32-3.46; P <0.001), mesiodistal crown-root angulation (95% CI, 4.09-15.95; P = 0.001), and labiolingual crown-root angulation (95% CI, -18.69 to -4.70; P = 0.002). Etiologic factors did not alter the dimensions of incisors (95% CI, -1.17 to 0.76; P = 0.672). According to the multiple linear regression the independent variables associated with root length of contralateral and impacted incisors were sex (ß = -0.904; 95% CI, -1.62 to - 0.19; P = 0.014) and the presence of impaction (ß = -2.87; 95% CI, -3.67 to -2.07; P <0.001). CONCLUSIONS: Regardless of their etiology, the impacted incisors showed roots that were 2.89 mm shorter than the contralateral incisors and had greater angulation in the mesiodistal and labiolingual directions. Girls showed a reduction of 0.904 mm (7.6%) on the lengths of roots of both impacted and contralateral central incisors. The presence of impaction led to a reduction of 25% in incisor root lengths. Approximately 30% of the impacted teeth showed crown-root angulations >20° resulting in an increased distal and labial angulation of the root apical portion.

Speech performance in adult patients undergoing Invisalign treatment.

OBJECTIVES: To assess speech performance of adult patients undergoing orthodontic treatment with Invisalign. MATERIALS AND METHODS: Twenty-four adult patients with Invisalign (Invisalign group: 6 men, 18 women; average age; 34.88 years) and 20 adult patients with fixed labial appliances (fixed group: 5 men, 15 women; average age; 38.85 years) were evaluated. Speech was recorded immediately before delivery of the first set of clear aligners or bonding of labial appliances (T0), immediately after delivery or bonding (T1), and 2 months after delivery or bonding (T2). Speech was evaluated via a combination of three auditory analyses: (1) objective acoustic analysis through digital sonography, (2) semiobjective assessment by six speech and language pathologists, and (3) subjective assessment patient questionnaire. RESULTS: The objective acoustic analysis showed a statistically significant difference over time from T0 to T1, T1 to T2, and T0 to T2 for Invisalign patients. The semiobjective analysis revealed a significant speech alteration from T0 to T1 and T1 to T2 for both groups, and from T0 to T2 in the Invisalign group. The subjective analysis showed a significant difference between means of Invisalign and fixed group patient perception at both T1 and T2. CONCLUSIONS: Invisalign treatment significantly affected speech, and although patients experience some level of adaptation, speech does not return to normal after 2 months of treatment.

Is there a better interceptive treatment for unerupted palatally displaced canines? A network meta-analysis

Abstract This systematic review aimed to investigate if there is a better interceptive treatment for palatally displaced canines (PDC) in the mixed dentition stage. The PubMed/MEDLINE, CENTRAL, Scopus, and EMBASE databases were searched for randomized clinical trials related to the research topic. The gray literature and reference lists were also assessed. Network meta-analysis was conducted to analyze the effects of different approaches on PDC eruption. The surface under the cumulative ranking area was calculated to rank the treatments. The certainty of the evidence was evaluated using the GRADE approach. Of the 892 eligible studies, 18 were selected for full-text analysis and 9 for meta-analysis, involving 506 participants and 730 PDC, to compare 9 approaches. The proportion of erupted PDC was significantly higher for all interceptive treatments compared with control (no intervention). Furthermore, the proportion of erupted PDC was higher in patients subjected to rapid maxillary expansion (RME) than those who underwent double extraction of primary canine and primary molar (relative risk (RR) = 2.68 ICr95%: 1.12-9.35). A higher proportion of erupted PDC was found for RME (RR = 3.07 ICr95%: 1.31-10.67), RME plus use of transpalatal arch (TA) plus extraction of primary canine(s) (EC) (RR = 1.43 ICr95%: 1.09-1.95), EC plus use of cervical pull headgear (RR = 1.38 ICr95%: 1.11-1.79), and EC plus use of TA (RR = 1.36 ICr95%: 1.00-1.9) than for EC. RME was most likely to be considered as the best interceptive treatment. Overall, the certainty of the evidence was considered low due to imprecision and indirectness. In conclusion, no intervention in the mixed dentition stage is the worst choice for PDC.

The effect of adenotonsillectomy and rapid maxillary expansion on the upper airway in pediatric obstructive sleep apnea: a randomized crossover-controlled trial.

STUDY OBJECTIVES: We aimed to determine the effects of adenotonsillectomy (AT) and rapid maxillary expansion (RME) on the apnea-hypopnea index (AHI) and compare volumetric changes in the upper airway (UA) arising from AT and RME. METHODS: Thirty-nine children who presented with maxillary constriction and grade III/IV tonsillar hypertrophy were randomized into two groups. One group underwent AT as the first treatment, and the other group underwent RME. Polysomnography (PSG) and cone-beam computed tomography (CBCT) were conducted before (T0) and 6 months after the first treatment (T1). In a crossover design, individuals with AHI>1 received the second treatment. Six months later, they underwent PSG and CBCT (T2). The influence of age, sex, tonsil and adenoid hypertrophy, initial AHI severity, initial volume of the UA, first treatment, and maxillary expansion amount was evaluated using linear regression analysis. Intra- and inter-group comparisons for AHI and inter-group comparisons of volumetric changes in each region of the UA were performed using a paired t-test and Wilcoxon test. RESULTS: The initial AHI severity and therapeutic sequence in which AT was the first treatment explained for 95.6% of AHI improvement. AT caused significant improvements in the AHI and volumetric increases in the buccopharynx and total UA areas compared to RME. CONCLUSIONS: The initial AHI severity and AT as the first treatment accounted for most of the AHI improvement. Most reductions in AHI were due to AT, which promoted more volumetric increases in UA areas than RME. RME may have a marginal effect on pediatric obstructive sleep apnea.

The effect of 4 first premolar extractions on the posterior Bolton ratio.

INTRODUCTION: Overall and anterior Bolton ratios have been well covered in the orthodontic literature; however, little has been reported on posterior Bolton ratios. Considering the frequency of premolar extractions in the specialty, it would be relevant to know how the posterior occlusion is affected by premolar extractions. This study aimed to investigate how the posterior Bolton ratio is affected by the extraction of the 4 first premolars. METHODS: Fifty-five patients with Class I occlusion within 1 standard deviation of ideal anterior and overall Bolton ratios models were selected and digitized. Tooth widths were measured. Virtual extractions of 4 first premolars were performed, and a digital setup of anterior and remaining posterior teeth observing ideal occlusion relationships was executed. When space closure compromised the occlusion, preference was given to the latter. Residual interproximal spacing was digitally measured on the setups. Analysis of variance and linear regression tests were used to identify factors contributing to interproximal spacing. RESULTS: An average of 1.1 mm of net residual spacing between mandibular second premolars and first molars was observed. In 27% of the sample, at least 1.5 mm of residual space was found. In addition, 16% showed at least 2 mm of residual space. The ratio of the maxillary second premolars to the mandibular second premolars and the width of the maxillary second premolars best explain residual space (r = 0.554; r2 = 0.307). A regression equation for predicting residual space is offered. CONCLUSIONS: Ideal anterior, posterior, and overall Bolton ratios treated with extraction of 4 first premolars and ideal occlusion will likely finish with some spacing in the mandible.

Bone changes in the mandibular incisors after orthodontic correction of dental crowding without extraction: A cone-beam computed tomographic evaluation.

PURPOSE: This study aimed to evaluate changes of the alveolar bone and interdental bone septum of the mandibular incisors through cone-beam computed tomography (CBCT) after orthodontic treatment of mandibular dental crowding without dental extraction. MATERIALS AND METHODS: The sample consisted of 64 CBCT images (32 pre-treatment and 32 post-treatment) from 32 adult patients with class I malocclusion and an average age of 23.0±3.9 years. The width and height of the alveolar bone and interdental septum, the distance between the cementoenamel junction (CEJ) and the facial and lingual bone crests, and the inclination of the mandibular incisors were measured. RESULTS: The distance between the CEJ and the marginal bone crest on the facial side increased significantly (P<0.05). An increased distance between the CEJ and the bone crest on the facial and lingual sides showed a correlation with the irregularity index (P<0.05); however, no significant association was observed with increasing mandibular incisor inclination (P>0.05). The change in the distance between the CEJ and the marginal bone crest on the facial side was correlated significantly with bone septum height (P<0.05). CONCLUSION: Bone dehiscence developed during the treatment of crowding without extraction only on the incisors' facial side. Increasing proclination of the mandibular incisor was not correlated with bone dehiscence. The degree of dental crowding assessed through the irregularity index was associated with the risk of developing bone dehiscence. The interdental septum reflected facial marginal bone loss in the mandibular incisors.

Enamel thickness of maxillary canines evaluated with microcomputed tomography scans.

INTRODUCTION: Enameloplasty of maxillary canines is often needed for aesthetic substitution in patients with congenitally missing lateral incisors. The exact enamel thicknesses for the various canine surfaces are unknown because previous studies failed to employ accurate measurement tools to report and compare detailed enamel thicknesses for each surface at various crown heights. METHODS: Thirty-two extracted maxillary canines were collected and scanned in a microcomputed tomography scanner. The scans were imported into a custom-written MATLAB software (version 9.2; MathWorks, Natick, Mass) and the enamel thickness on the mesial, distal, labial, fossa, cingulum, and incisal edge of each tooth was computed, obtaining the mean value from slices at 0.1 mm intervals. The overall mean enamel thickness for each surface was also calculated, and these values were compared using paired t tests. Incisal wear stage and incisal enamel thickness that was measured were compared using Spearman rank correlation coefficient. RESULTS: The mean enamel thickness was significantly thinner at the gingival level when compared with the incisal for all surfaces that were analyzed (1-tailed, P <0.001). The mean enamel coverage at the mesial was significantly thinner than the distal when measured gingival to the widest mesiodistal area. The mean enamel coverage of the cingulum was particularly thin and therefore requires extreme care in reshaping it. Incisal edge enamel thickness was highly negatively correlated with the wear stage of the scoring system that was used (1-tailed, P <0.001). CONCLUSIONS: The enamel coverage of the maxillary canine varies depending on the tooth surface and the incisogingival measurement location.

Esthetic perception of clear aligner therapy attachments using eye-tracking technology.

INTRODUCTION: The purpose of this research was to assess and compare esthetic perceptions of clear aligner therapy with attachments and esthetic brackets by measuring differences in eye fixations using eye-tracking technology. METHODS: The sample involved 250 adult subjects. The subjects gave verbal consent, then viewed photographs showing 4 variations of orthodontic appliances: clear aligner control with minimal attachments, clear aligner with anterior and posterior attachments, esthetic brackets, and clear aligner with posterior attachments. Images were displayed for 6 seconds each on a computer monitor. Location and time to first fixation, total fixation duration, and total visit count and duration for each type of appliance were measured. Subjects were then asked to complete an online survey. RESULTS: Participants spent the least amount of time looking at the photograph of the control, followed by those of the ceramic brackets, posterior attachments, and anterior and/or posterior attachments. The anterior and/or posterior image had the least number of visits but garnered the longest visit duration (1.32 visits averaging 0.74 seconds per visit). This was followed by the images of the posterior attachments (1.40 visits, 0.70 seconds per visit), ceramic brackets (1.43 visits, 0.65 seconds per visit), and minimal attachments control (1.45 visits, 0.61 seconds per visit). The hierarchy of most preferred appliances across all 250 respondents was as follows: minimal attachments control, ceramic brackets, posterior attachments, and anterior and/or posterior attachments. Overall, 88.4% of subjects would compromise appliance esthetics during treatment for a better outcome (n = 221). CONCLUSIONS: Eye-tracking data show that time to the first fixation was negatively correlated with its survey ranking and that an increase in attachments led to an increase in total fixation duration. There is a general desire for clear aligners without attachments and ceramic brackets over clear aligners with multiple attachments. Survey data suggest that although respondents viewed appliance esthetics as highly important, nearly all would compromise appliance esthetics during treatment if it resulted in a better outcome.

Nonsurgical treatment of skeletal maxillary protrusion with gummy smile using headgear for growth control, mini-implants as anchorage for maxillary incisor intrusion, and premolar extractions for incisor retraction.

INTRODUCTION: An adolescent girl, aged 12 years 11 months, was evaluated for orthodontic treatment. Her chief complaints included a difficulty with keeping her lips passively closed and excessive gingival exposure upon smiling. Her treatment plan included (1) restriction of maxillary growth with cervical headgear, (2) extraction of the maxillary first premolars to reduce the maxillary protrusion and the mandibular second premolars to facilitate Class II dental correction, and (3) management of maxillary incisor intrusion via anchoring with mini-implants. When indicated, even in the absence of large space discrepancies, extractions can be beneficial to the patient. The final results showed an attractive smile, passive lip seal, and a more esthetic and balanced facial profile. Retention records confirmed the stability of the treatment. The 5-year follow-up visit revealed that the treatment results were quite stable.

Long-term stability of maxillary and mandibular arch dimensions when using rapid palatal expansion and edgewise mechanotherapy in growing patients.

OBJECTIVE: The purpose of this study was to assess the long-term stability of rapid palatal expansion (RPE) followed by full fixed edgewise appliances. METHODS: This study included 67 patients treated using Haas-type RPE and non-extraction edgewise appliance therapy at a single orthodontic practice. Serial dental casts were obtained at three different time points: pretreatment (T1), after expansion and fixed appliance therapy (T2), and at long-term recall (T3). The mean duration of the T1-T2 and T2-T3 periods was 4.8 ± 3.5 years and 11.0 ± 5.4 years, respectively. The dental casts were digitized, and the computed measurements were compared with untreated reference data. RESULTS: The majority of treatment-related increases in the maxillary and mandibular arch measurements were statistically significant (p < 0.05) and greater than expected for the untreated controls. Although many measurements decreased postretention (T2-T3), the net gains persisted for all of the measurements evaluated. CONCLUSIONS: The use of RPE therapy followed by full fixed edgewise appliances is an effective method for increasing maxillary and mandibular arch width dimensions in growing patients.

Three-dimensional evaluation of craniofacial characteristics related to mandibular asymmetries in skeletal Class I patients.

INTRODUCTION: Our objective was to analyze the characteristics that affect skeletal Class I adults with mandibular asymmetries using cone-beam computerized tomography. METHODS: The sample included cone-beam computerized tomography images of 120 subjects. Asymmetry was determined by the deviation of gnathion from the midsagittal plane and classified as relative symmetry, moderate asymmetry, or severe asymmetry. Maxillary and mandibular measurements were made, and the differences between the contralateral side and the deviated side were evaluated, as well as the differences between the categories of asymmetry. RESULTS: For patients with moderate asymmetry, there were significant differences between the contralateral and deviated sides for some measuments in the transverse and vertical planes. For those with severe asymmetry, statistically significant differences were found between the sides for all measurements, except for the measuments that evaluated the position of the mandibular condyle in the transverse and sagittal directions. Furthermore, a strong correlation was found in patients with severe asymmetry, between the deviation of the mandibular dental midline and the lateral displacement of gnathion. CONCLUSIONS: Patients with relative symmetry had a bilateral balance, whereas those with moderate and severe asymmetries showed several skeletal imbalances. A great deviation of the mandibular dental midline may indicate severe skeletal asymmetry in Class I adults.

Orthodontic treatment of a patient with maxillary lateral incisors with dens invaginatus: 6-year follow-up.

INTRODUCTION: Dens invaginatus is an anomaly of dental development in which calcified tissues, such as enamel and dentin, are invaginated into the pulp cavity. This morphologic alteration is more frequent in maxillary permanent lateral incisors and makes them more susceptible to carious lesions and pulp alterations. METHODS: This case report describes a patient with maxillary lateral incisors affected by dens invaginatus. The maxillary right lateral incisor had already undergone endodontic treatment, and the maxillary left one had a periapical lesion. Additionally, the patient had a Class II Division 1 malocclusion, with anterior open bite, posterior crossbite, and an impacted mandibular left second molar. RESULTS: The orthodontic treatment involved extraction of the maxillary lateral incisors and 2 mandibular premolars, resulting in proper overjet and overbite with good arch coordination and occlusal stability. CONCLUSIONS: Treatment results were stable, as evaluated in a 6-year posttreatment follow-up.

Cephalometric evaluation of adult anterior open bite non-extraction treatment with Invisalign.

OBJECTIVE: The purpose of this study was to evaluate, by means of cephalometric appraisal, the vertical effects of non-extraction treatment of adult anterior open bite with clear aligners (Invisalign system, Align Technology, Santa Clara, CA, USA). METHODS: Lateral cephalograms of 30 adult patients with anterior open bite treated using Invisalign (22 females, 8 males; mean age at start of treatment: 28 years and 10 months; mean anterior open bite at start of treatment: 1.8 mm) were analyzed. Pre- and post-treatment cephalograms were traced to compare the following vertical measurements: SN to maxillary occlusal plane (SN-MxOP), SN to mandibular occlusal plane (SN-MnOP), mandibular plane to mandibular occlusal plane (MP-MnOP), SN to mandibular plane (SN-MP), SN to palatal plane (SN-PP), SN to gonion-gnathion plane (SN-GoGn), upper 1 tip to palatal plane (U1-PP), lower 1 tip to mandibular plane (L1-MP), mesiobuccal cusp of upper 6 to palatal plane (U6-PP), mesiobuccal cusp of lower 6 to mandibular plane (L6-MP), lower anterior facial height (LAFH), and overbite (OB). Paired t-tests and descriptive statistics were utilized to analyze the data and assess any significant changes resulting from treatment. RESULTS: Statistically significant differences were found in overall treatment changes for SN-MxOP, SN-MnOP, MP-MnOP, SN-MP, SN-GoGn, L1-MP, L6-MP, LAFH, and OB. CONCLUSIONS: The Invisalign system is a viable therapeutic modality for non-extraction treatment of adult anterior mild open bites. Bite closure was mainly achieved by a combination of counterclockwise rotation of the mandibular plane, lower molar intrusion and lower incisor extrusion.