Criteria for early diagnosis of third molar agenesis: a retrospective radiographic study.

OBJECTIVE: To explore the association between chronological, dental and skeletal ages and early diagnosis of third molars agenesis. MATERIAL AND METHODS: This retrospective radiographic study comprised a sample of 282 Portuguese patients (122 males and 160 females) who sought orthodontic treatment between 2007 and 2018. Each participant had panoramic and lateral cephalometric radiographs performed before and after the age of 14 years. The chronological age was categorized into three intervals between 11.0 and 13.11 years of age. The full eruption of the four-second molars was used as a criterion in determining dental age. Skeletal age was verified by the vertebral maturation method. The diagnosis of agenesis of third molars was initially performed by observation of the initial panoramic radiography undertaken before the age of 14 years. Subsequently, the diagnosis of agenesis of third molars was confirmed by visualizing the second panoramic radiography, obtained after the age of 14 years. The association between the accuracy of the diagnosis and the chronological, dental and skeletal ages was evaluated using the chi-square test, at a 5% significance level. RESULTS: No significant association between chronological age and alterations in the diagnosis of third molar agenesis was identified. However, there was a significant association between third molar agenesis and both dental age (p<0.001) and skeletal age (p=0.006). CONCLUSION: The eruption of the four-second molars and the peak of growth could be considered as criteria for early diagnosis of third molar agenesis, whereas chronological age is not a reliable diagnostic indicator.

Criteria for early diagnosis of third molar agenesis: a retrospective radiographic study

ABSTRACT Objective: To explore the association between chronological, dental and skeletal ages and early diagnosis of third molars agenesis. Material and Methods: This retrospective radiographic study comprised a sample of 282 Portuguese patients (122 males and 160 females) who sought orthodontic treatment between 2007 and 2018. Each participant had panoramic and lateral cephalometric radiographs performed before and after the age of 14 years. The chronological age was categorized into three intervals between 11.0 and 13.11 years of age. The full eruption of the four-second molars was used as a criterion in determining dental age. Skeletal age was verified by the vertebral maturation method. The diagnosis of agenesis of third molars was initially performed by observation of the initial panoramic radiography undertaken before the age of 14 years. Subsequently, the diagnosis of agenesis of third molars was confirmed by visualizing the second panoramic radiography, obtained after the age of 14 years. The association between the accuracy of the diagnosis and the chronological, dental and skeletal ages was evaluated using the chi-square test, at a 5% significance level. Results: No significant association between chronological age and alterations in the diagnosis of third molar agenesis was identified. However, there was a significant association between third molar agenesis and both dental age (p<0.001) and skeletal age (p=0.006). Conclusion: The eruption of the four-second molars and the peak of growth could be considered as criteria for early diagnosis of third molar agenesis, whereas chronological age is not a reliable diagnostic indicator.

RESUMO Objetivo: Explorar a associação entre as idades cronológica, dentária e esquelética e o diagnóstico precoce da agenesia dos terceiros molares. Material e Métodos: Este estudo radiográfico retrospectivo compreendeu uma amostra de 282 pacientes portugueses (122 homens e 160 mulheres) que procuraram tratamento ortodôntico entre 2007 e 2018. Cada participante tinha radiografias panorâmicas e cefalométricas laterais realizadas antes e depois dos 14 anos de idade. A idade cronológica foi categorizada em três intervalos entre 11,0 e 13,11 anos de idade. A erupção completa dos quatro segundos molares foi usada como critério para determinar a idade dentária. A idade esquelética foi verificada pelo método de maturação das vértebras cervicais. O diagnóstico de agenesia de terceiros molares foi inicialmente realizado pela observação da radiografia panorâmica inicial, realizada antes dos 14 anos de idade. Posteriormente, o diagnóstico de agenesia de terceiros molares foi confirmado pela visualização da segunda radiografia panorâmica, obtida após os 14 anos de idade. A associação entre a acurácia do diagnóstico e as idades cronológica, dentária e esquelética foi avaliada por meio do teste qui-quadrado, com nível de significância de 5%. Resultados: Não foi identificada associação significativa entre idade cronológica e alterações no diagnóstico de agenesia de terceiros molares. No entanto, houve associação significativa entre agenesia de terceiro molar e idade dentária (p<0,001) e idade óssea (p=0,006). Conclusão: A erupção dos quatro segundos molares e o pico de crescimento podem ser considerados critérios para o diagnóstico precoce da agenesia do terceiro molar, enquanto a idade cronológica não é um indicador diagnóstico confiável.

Perception of Need for Further Refinement in a Clear Aligner Treatment among Orthodontists, Dentists and Laypeople: A Retrospective Study.

Clear aligner treatment often requires further refinement to improve the orthodontic treatment outcome. However, the perceptions of treatment outcomes evaluated by orthodontists and dentists are sparse, and laypeople's perceptions have yet to be explored. Here, we explore the perceptions of orthodontists, dentists, and laypeople concerning the treatment outcomes achieved after completing the first sequence of aligners. This cross-sectional study involved 37 orthodontists, 67 dentists, and 93 laypeople. We administered an online questionnaire containing intra-oral photographs of nine completed cases with pre- and post-first sequences of aligners. As a control, we used a digital prediction system for the treatment outcome. Self-perception was reported using a visual analog scale. Both orthodontists and dentists had similar perceptions about treatment outcomes (p = 0.363) but significantly differed from laypeople (p ≤ 0.0001). Both orthodontists and dentists recommended further treatment; orthodontists were more critical than dentists (p ≤ 0.001). Orthodontists were more critical than dentists in their evaluations of the need for further treatments; however, their perceptions of treatment outcomes were similar. Laypeople were more satisfied with the treatment outcomes, were less concerned with occlusion, and were more focused on the aesthetic results of the treatment.

Different manifestations of Class II Division 2 incisor retroclination: a morphologic study.

INTRODUCTION: The aims of this study were to investigate whether there is a different transverse morphologic pattern of dental arches among patients with different manifestations of Class II Division 2 incisor retroclination and to evaluate to what extent the pattern of smaller-than-average teeth in Class II Division 2 malocclusion is common to all groups studied. This information might clarify whether different Class II Division 2 phenotypes represent a single etiology or multiple etiologies. METHODS: The sample comprised 108 subjects with Class II Division 2 malocclusions, divided into 2 groups according to the type of incisor retroclination: group I included 43 Class II Division 2 subjects with retroclination exclusively of the maxillary central incisors, and group II included 65 Class II Division 2 subjects with retroclination of the 4 maxillary incisors. Maxillary and mandibular intercanine and intermolar widths as well as mesiodistal crown dimensions of the 4 maxillary and mandibular incisors were determined from the patients' initial study models. Mean values of all variables were compared between the 2 groups by sex with analysis of variance. RESULTS: From the comparison between these 2 groups, no statistically significant differences were found for all transverse measurements (P >0.05). For all mesiodistal measurements analyzed, statistically significant differences between the groups were only found for the mean value of both maxillary lateral incisors' mesiodistal dimensions in both sexes (P <0.05). CONCLUSIONS: It is not possible to attribute a characteristic pattern of dental arch-width and incisor mesiodistal dimensions to the different manifestations of incisor retroclination in Class II Division 2 malocclusion.