WNT10A coding variants and maxillary lateral incisor agenesis with associated dental anomalies

Congenital maxillary lateral incisor agenesis (MLIA) is one of the most common subtypes of dental agenesis. Because little is known with regard to the aetiology of this anomaly, the aim of the study was to determine the contribution of nucleotide variants in wingless‐type MMTV integration site family, member 10A (WNT10A), msh homeobox 1 (MSX1), and paired box 9 (PAX9) to the risk of MLIA in a Polish population. Coding regions of the selected genes were analysed by direct sequencing in a group of 20 individuals with unilateral and bilateral MLIA, associated or not with other dental anomalies. The frequencies of the identified nucleotide variants were assessed in an additional cohort of patients with isolated dental agenesis (n = 147) and in 178 controls. Mutation screening showed four non‐synonymous substitutions located in the highly conserved coding sequence of WNT10A in five (25%) of the 20 patients. Analysis of genotyping results revealed that three of these variants – p.Arg113Cys, p.Phe228Ile, and the newly identified p.Arg171Leu – may represent aetiological mutations underlying MLIA with associated dental anomalies. No mutations that were potentially aetiologic were identified in MSX1 and PAX9. In conclusion, this is the first report implicating coding variants in the WNT10A gene in the aetiology of MLIA. These results will require further confirmation using larger‐scale studies.     

Single maxillary central incisor in association with mid-line anomalies

A single maxillary central incisor may occur as an isolated dental finding. However, it has also been reported to occur in association with autosomal dominant holoprosencephaly, in association with growth retardation with or without growth hormone deficiency and occasionally in association with other mid-line developmental defects. Holoprosencephaly and pituitary dysfunction are two specific examples of mid-line defects and this report emphasises that other mid-line defects may be associated with a single maxillary central incisor. We recommend that patients with this dental anomaly should be referred for a detailed medical examination.     

Investigation of the maxillary lateral incisor agenesis and associated dental anomalies in an orthodontic patient population

Objectives: The aim of this study was to investigate the prevalence of maxillary lateral incisor (MLI) agenesis and associated dental anomalies as well as skeletal patterns in an orthodontic population, and then to compare it with the prevalence of these anomalies in the general population.Study Design: The material of the present study included the records of the 3872 orthodontic patients. The followings were recorded for each subject with the agenesis of MLI: Age, sex, unilateral or bilateral absence, anterior-posterior skeletal relationship of the maxilla and mandible, and presence of associated dental anomalies. The occurrence of these anomalies was compared with data previously reported for the general populations. Results: Of the 3872 patients examined, 94 were found to have agenesis of the MLI, representing a prevalence of 2.4 per cent, with females being more frequently observed. The most commonly found associated anomalies were ectopic eruption of maxillary canines and reduced or peg- shaped contralateral incisor with the frequencies of 21.3 per cent and 20.2 per cent respectively.Conclusions: Patients with agenesis of MLI showed a significantly higher prevalence of skeletal Class III malocclusion compared with the general population. The prevalence of ectopic eruption, transposition, and transmigration of the maxillary canine and reduced or peg- shaped MLIs were significantly increased. Key words:Hypodontia, missing laterals, associated dental anomalies.     

Changes in maxillary incisor dental pulp blood flow during intrusion by mini-implants

Aim. The aim of this clinical study was to identify changes in pulpal blood flow (PBF) in human central incisors resulting from short- and long-term intrusive orthodontic forces from mini-implants. Materials and methods. A total of 40 sound upper central and lateral incisors in 20 patients scheduled for intrusion for orthodontic reasons were divided into two groups. From each group, 20 teeth were subjected to intrusive force from mini-implants (Group 1 = Light Force: 40 g; Group 2 = Heavy Force: 120 g), whereas the remaining 20 contralateral teeth were not subjected to forces from mini-implants and served as controls. Laser-Doppler flowmetry (LDF) measurements were recorded at baseline and at 3 days and 3 weeks following intrusion. Results. PBF decreased significantly at 3 days (Light Force Group: 7.72 ± 0.50; Heavy Force Group: 7.72 ± 0.52) and then increased towards baseline at 3 weeks (Light Force Group: 10.37 ± 0.58; Heavy Force Group: 10.31 ± 0.45) following intrusion. Conclusions. In other words, despite slight regressive changes in pulpal tissue in the short-term, PBF improved after 3 weeks following intrusion by mini-implants, indicating that the changes observed in PBF is reversible, even following radical incisor intrusion.     

Immediate implant placement in the maxillary central incisor region: a case report

PATIENT: A 67-year-old female with root fracture of the maxillary central incisor underwent implant placement immediately after extraction, with the goal of shortening the treatment period. The superstructure was placed on the implant after a 4-month healing period. Review 5 years after implant loading revealed no clinical problems. DISCUSSION AND CONCLUSION: The treatment time was shortened effectively by the flapless immediate post-extraction placement procedure. Immediate post-extraction implant placement based on proper examination and diagnosis would reduce the patient burden.     

Maxillofacial growth and dental implants in the maxillary anterior region

Single tooth replacement with a dental implant is an increasingly popular solution in patients with loss of an upper anterior tooth. There is a risk, however, of placing the implant prematurely in youths. In a case series the effects of residual maxillary growth on the results of implant treatment in the anterior maxillary region were measured. The results confirm findings from other studies on this subject and indicate that cessation and degree of vertical growth are unpredictable. This may result in infraposition of the implant and lead to periodontal bone loss around the implant region and its neighbouring teeth. Clinicians should be aware of this and inform their patients that these changes may eventually compromise the aesthetic result of the treatment.     

Radiographic assessment of dental anomalies in patients with ectopic maxillary canines

Background.  The aetiology of palatally and labially located ectopic maxillary canines is multifactorial. Accordingly, early prediction of this eruptional disturbance is in most cases not possible.
Aim.  The purpose of this study was to analyse dental deviations in cases with either palatal or labial ectopic canines.
Design.  Panoramic and intra-oral radiographs from 50 patients with palatally located (38 females and 12 males) and 19 patients with labially located ectopic canines (11 females and 8 males), aged 10 years, 2 months–18 years, 1 month, were analysed. Dental deviations registered were crown and root malformations, agenesis, and eruption deviations. Registrations were performed in the maxillary incisor field and in the dentition in general.
Results.  The study documented that palatally as well as labially located ectopic canines can occur in dentitions without other dental deviations. Dental deviations occurred in approximately two-thirds of all cases, more often in females and in cases with palatally located canines. More than half of the females with palatally located canines had deviations in the maxillary incisors and in the dentition in general.
Conclusion.  Dental deviations may be considered a risk factor for maxillary canine ectopia. Early identification of patients at risk and appropriate interceptive treatment may reduce ectopic eruption of maxillary canines.     

Unusual case of internal resorption in cervical region of maxillary left lateral incisor

We treated an unusual case of internal resorption of the maxillary left lateral incisor seen in a 15-year-old female. The patient was referred to our clinic complaining of repeated cold pain and spontaneous pain in the maxillary left lateral incisor region. An intraoral examination revealed that the tooth was a microdont with a large tubercle, with a pink spot observed in the mesiopalatal area, while radiograph revealed an unusual radiolucent lesion in the cervical area of the affected tooth. Our diagnosis was internal resorption and the affected tooth symptoms ceased after a pulpectomy was performed. Over the next 3 years, periodical examinations performed at 3-month intervals did not reveal further resorption.