Maxillary lateral incisor agenesis and microdontia: Minimally invasive symmetric and asymmetric esthetic rehabilitation

Maxillary lateral incisor agenesis is a condition that significantly compromises smile esthetics, which is particularly worrying in young patients. This article shows how the combination of non-invasive treatments and current restorative options may improve clinical outcomes following orthodontic treatment for symmetric and asymmetric maxillary lateral incisor agenesis and microdontia. Teeth were treated with conservative resin restorations in three separate cases: two of congenitally missing maxillary lateral incisors (i.e., unilateral and bilateral) and one of microdontia. After presenting the clinical results, this article summarizes how bleaching, enameloplasty, and bonding with composite resin can enhance esthetics and functions following orthodontic space closure. The cases reveal that carefully planned, methodically executed orthodontic and restorative approaches can achieve predictable, esthetic outcomes that will improve the patient’s self-esteem with a minimally invasive solution.

Analyses of oligodontia phenotypes and genetic etiologies

Oligodontia is the congenital absence of six or more teeth and comprises the more severe forms of tooth agenesis. Many genes have been implicated in the etiology of tooth agenesis, which is highly variable in its clinical presentation. The purpose of this study was to identify associations between genetic mutations and clinical features of oligodontia patients. An online systematic search of papers published from January 1992 to June 2021 identified 381 oligodontia cases meeting the eligibility criteria of causative gene mutation, phenotype description, and radiographic records. Additionally, ten families with oligodontia were recruited and their genetic etiologies were determined by whole-exome sequence analyses. We identified a novel mutation in WNT10A (c.99_105dup) and eight previously reported mutations in WNT10A (c.433 G > A; c.682 T > A; c.318 C > G; c.511.C > T; c.321 C > A), EDAR (c.581 C > T), and LRP6 (c.1003 C > T, c.2747 G > T). Collectively, 20 different causative genes were implicated among those 393 cases with oligodontia. For each causative gene, the mean number of missing teeth per case and the frequency of teeth missing at each position were calculated. Genotype–phenotype correlation analysis indicated that molars agenesis is more likely linked to PAX9 mutations, mandibular first premolar agenesis is least associated with PAX9 mutations. Mandibular incisors and maxillary lateral incisor agenesis are most closely linked to EDA mutations.

Orthodontic Space Closure of a Missing Maxillary Lateral Incisor Followed by Canine Lateralization

Maxillary lateral incisor agenesis is the most prevalent developmental dental anomaly. The management of missing lateral incisor was either closure using canine as substitution or creation of space orthodontically for prosthetic replacement. A careful diagnosis and treatment plan are deemed essential to address the patient’s needs as the spacing is present in the esthetic region. Such problem is very challenging for orthodontists, prosthodontists, and general practitioners. This case report describes the orthodontic management of a 22-year-old adult female patient with missing upper left lateral incisor tooth and upper anterior spacing by closing the space with canine lateralization and reshaping to simulate it with the lateral incisor. However, some modifications in the treatment mechanics are crucial to achieve the optimal esthetic and to improve the occlusion. Space closure with canine lateralization option seems less invasive, treatment can be completed relatively in a short period of time, and its adaptation with the facial changes throughout life without having artificial prosthesis provided other factors favoring for this option.

Prevalence, distribution, and age at clinical detection of missing permanent incisors

Summary Objectives To determine the prevalence and distribution of clinically missing permanent incisors, and the age at which they are detected, in school-aged children. Methods A total of 2573 children aged 4–13 underwent oral health screening on at least one occasion between 2001 and 2017. In order to define a threshold age, after which permanent incisor agenesis could be suspected clinically with reasonable certainty, children who had been seen for at least three consecutive years, with any clinically missing permanent incisor were selected (n = 19). The maximum age of detection among these children was chosen as the threshold age. Based on this, a total of 766 children at or above the threshold age were screened for a cross-sectional epidemiological survey. Chi-squared tests were used to compare the prevalence of clinically missing permanent incisors among boys and girls, comparing unilateral versus bilateral, and right- versus left-sided missing teeth. Results Roughly 2% of the sample presented with at least one clinically missing maxillary lateral incisor. This was bilateral in half of cases. Clinically missing mandibular incisors were found in 0.5% of children. Finally, the threshold age for clinical suspicion of maxillary lateral incisor agenesis was set at 11.5 years. Agenesis was confirmed in all of the children attending a follow-up radiographic visit. Conclusions Approximately 1 in 50 children present with a clinically missing maxillary lateral incisor. The age at suspicion of maxillary lateral incisor agenesis can sometimes be several years after its expected eruption, perhaps due to significant variation in eruption times.