Prevalence and distribution of dental V.P. Wagner1, T. Arrué2, E. Hilgert2, N. A. Arús3, H. L. D. da Silveira3, anomalies in a paediatric M. D. Martins4, J. A. Rodrigues2 1Academic Unit of Oral and Maxillofacial Pathology, School of Clinical Dentistry - population based on University of Sheffield, UK 2Paediatric Dentistry Division, School of Dentistry, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil panoramic radiographs 3Oral Radiology Division, School of Dentistry, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil 4Oral Pathology Division, School of Dentistry, analysis Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil DOI 10.23804/ejpd.2020.21.04.7 e-mail: [email protected] Abstract considered to be the main aetiological factors. Variations in the dental morphology and structure, for example, typically result from disturbances during embryological development. Aim To evaluate the frequency and distribution of dental Nevertheless, environmental factors that occur during the anomalies (DA) in a paediatric population. prenatal and postnatal development period can also trigger the Material and methods Panoramic digital radiographs of children between 6 and 12 years old performed at a reference centre development of DA, particularly positional abnormalities or for radiographic exams were accessed. Two calibrated examiners disorders in the eruption chronology [Vani et al., 2016; Laganà evaluated the radiographs. The association between variables and et al., 2017]. The identification of DA is important once they outcomes was assessed using non-parametric tests. The significance can cause disturbances such as malocclusion, increased level was set at 5%. susceptibility to caries and aesthetic issues [Mukhopadhyay and Results Five hundred and twelve individuals were included Mitra, 2014]. Therefore, an opportune identification can and 61.3% presented at least one DA. The mean age of patients minimise complications by allowing early treatment planning, with DA (9.35±1.60) was significantly higher compared to patients which is usually associated with less extensive interception and with no anomalies (7.90±1.58). Patients with supernumerary tooth, more favourable prognosis [Kapdan et al., 2012]. Moreover, DA however, were significantly younger. The most frequent DA were can involve isolated events or be part of specific syndromes permanent tooth radicular dilacerations (38.1%), permanent tooth [Bilge et al., 2017; Stevenson et al., 2015]. Therefore, dentists agenesis (29.3%), supernumerary tooth (6.4%) and impacted tooth can contribute to the diagnosis of such syndromes by identifying (6.4%). Anterior teeth and female patients were more affected by these abnormalities. Anomalous teeth are typically asymptomatic, radicular dilacerations. Dental agenesis was more frequent in the and identification by clinicians is frequently made via clinical or third molars followed by the upper lateral incisor. Conclusions DA are quite frequent in the paediatric population radiographic examination [Mukhopadhyay and Mitra, 2014]. and the most common DA observed herein could only be identified Among radiographic examinations, the panoramic radiograph through imaging exams. The most appropriate timing to perform represents an important tool since it provides a general view an investigation for the detection of dental anomalies appears to that allows a more comprehensive diagnosis. be between 9 and 10 years old. Knowledge of DA prevalence, severity (number of affected teeth) and distribution within the dental arch provides essential information for genetic and phylogenetic studies. Previous analyses have demonstrated some discrepancies in the frequency KEYWORDS Disturbances in dental development; Growth and of DA, probably due to inherent variations of each suited development; Radiology. population or to the different diagnostic criteria used by researchers [Altug-Atac and Erdem, 2007; Vani et al., 2016; Laganà et al., 2017; Mukhopadhyay and Mitra, 2014; Kapdan et al., 2012; Bilge et al., 2017]. We believe that it is important to include a representative sample with no significant bias, such Introduction as only orthodontic patients, to provide a more accurate estimate of the prevalence of DA in the target population. Furthermore, Dental anomalies (DA) involve abnormalities in the number, the establishment of rigid criteria is of paramount importance size and shape of teeth, structural defects or even eruption to allow reproducibility and permit to identify the causes of pattern disruptions [Altug-Atac and Erdem, 2007]. The precise eventual inconsistencies with previous studies. Concerning the aetiology of DA is complex and not completely understood. targeted population, studies that focus on paediatric patients Genetic and epigenetic defects throughout the morpho- or are highly desired once the early identification of DA in these histo-differentiation stages of dental development have been patients is more likely to have a larger influence on treatment 292 EUROPEAN JOURNAL OF PAEDIATRIC DENTISTRY VOL. 21/4-2020 DENTAL RADIOGRAPHS FOR INFANT, CHILDREN AND ADOLESCENT Dental anomaly Criteria strategies and prognosis. Nevertheless, the literature is not clear Tooth that is far larger than its contralateral concerning the most opportune age to identify DA in children. homolog, “ovelfills” its space in the dental arch or This information may contribute during childcare, suggesting Macrodontia seems bigger because of exaggerated dimensions an ideal timing to identify DA in this population. (conical, shaped or tapered) (Bilge et al., 2017) The aim of the present study was to evaluate the frequency, Size Tooth that is far smaller than its contralateral severity and pattern of DA distribution, through the examination homolog, does not “fill” its space in the dental arch of panoramic digital radiographs, in a paediatric population Microdontia or seems small because of the lack of expected shape that attended a reference centre for radiographic examinations (conical, shaped or tapered) (Bilge et al., 2017) in southern Brazil. No sign of crown calcification on the radiograph considering the chronological age of dental eruption. The absence of teeth was classified in hypodontia Subjects and methods Dental agenesis - agenesis of one to six teeth (excluding the third molars), oligodontia - absence of more than six Study design and sample teeth (excluding the third molars); and anodontia This cross-sectional study was conducted on digital panoramic - complete absence of teeth (Gracco et al., 2017) radiographs performed over a 3-year period (2014–2016) at Number Number Teeth formed in excess of the normal dentition, the Radiology Service of the Federal University of Rio Grande regardless of whether they were impacted or in Supernumerary do Sul Dental School. Information concerning age and gender occlusion. A supernumerary tooth located between tooth was recovered from the service files. The inclusion criteria the central incisors was considered a mesiodens included patients aged 6–12 years at the time of radiograph. (Pedreira et al., 2016) If more than one panoramic radiograph was available for the Union of two dental germs that would normally same child, only the first one was evaluated. Exclusion criteria be separated resulting in a double tooth. The were: incomplete records (panoramic radiograph, clinical notes), Fusion dental count reveals the lack of a tooth when the presence of syndromes that affect tooth development, or a anomalous tooth is counted as one (Neville et al., 2015) history of previous orthodontic treatment. Duplication of a single dental germ, resulting in the Data acquisition partial or total formation of two teeth that, however, All subjects included in the study had panoramic radiographs Gemination do not separate completely. Tooth counting is normal when the anomalous tooth is considered as one taken by an experienced technician using standardised methods (Neville et al., 2015) with the same x-ray device. The radiographs were taken using a CS 8000C (Carestream Health, Inc., Rochester, NY, USA) Union of two adjacent teeth just by the cement Concrescence panoramic radiographic device, with the following parameters: without dentin confluence (Neville et al., 2015) 90 kVp, 15 mA. The image acquisitions were performed with Abnormal angulation or sharp curvature of the dental Root dilaceration Trophy Dicom (Trophy Radiologie S.A., Marne la Vallée, France) root(Neville et al., 2015) Shape Shape software and stored in a digital database. Two calibrated Excessive non-neoplastic cement deposition along examiners manually performed the analysis. The calibration Hypercementosis the root, leading to root thickening (Neville et al., consisted of the study of dental anomalies in 30 panoramic 2015) radiographs previously selected by an experienced professional Elongated crowns and pulp chamber accompanied in imaging. Both primary and permanent dentitions were by a more apical location of the bifurcation area of considered. All analyses were conducted under standardised Taurodontism a multiradicular tooth (Pedreira et al., 2016; Neville lighting conditions, screen brightness and resolution. A third et al., 2015) experienced professional subsequently evaluated cases of Well-defined nodules with enamel-like radiopacity disagreement. The DA evaluated in this study and the criteria Enamel pearl along the root surfaces (Neville et al., 2015) for identification are detailed in Table 1. In addition to DA, Increased