Dental development defects (DDDs) are quantitative and/or qualitative alterations produced during odontogenesis that affect both primary and permanent dentition. The etiology remains unknown, being associated with prenatal, perinatal, and postnatal factors. The aims were to identify the possible etiological factors, as well as the prevalence of DDDs in the primary and permanent dentition in a pediatric population. Two hundred twenty-one children between 2 and 15 years of age, patients of the master’s degree in Pediatric Dentistry of the Complutense University of Madrid, were reviewed. DDDs were observed in 60 children. Next, a cross-sectional, case-control study was carried out (60 children in the control group and 60 children in the case group). The parents or guardians completed a questionnaire aimed at identifying associated etiological factors. The prevalence of DDDs in patients attending our master’s program in both dentitions was 27.15%. Otitis, tonsillitis, high fevers, and medication intake stood out as the most relevant postnatal factors among cases and controls. The permanent maxillary right permanent central incisor and the primary mandibular right second molar were the most affected; there were no differences in relation to gender. One out of three children who presented DDDs in the primary dentition also presented DDDs in the permanent dentition. Prenatal and postnatal etiological factors showed a significant relationship with DDD alterations, considered risk factors for DDDs in both dentitions.

Background/Objectives: Preclinical training in pediatric dentistry is traditionally performed on acrylic primary teeth or natural extracted teeth in phantoms or dental manikins. With technological advancements, virtual simulation has become increasingly common, enhancing the development of cognitive and motor skills in dental students while complementing traditional methods. Specific objectives included assessing whether preclinical theoretical knowledge impacts motor skill scores, comparing the quality of dental preparations on acrylic teeth versus those performed using virtual simulation (Simodont^®) and evaluating students’ perceptions of Simodont^® use. Methods: An observational, descriptive, cross-sectional study was conducted. Students first completed a theoretical knowledge survey on dental preparations, class II caries, and pulpotomies. They then performed dental preparations on both acrylic primary teeth and the Simodont^® simulator, with their work assessed by a pediatric dentistry professor. Finally, students completed a perception survey regarding their experience. Results: The introduction of the Simodont^® was positively received. Theoretical knowledge prior to preclinical exercises did not significantly influence practice scores. Average scores for preparations on acrylic teeth (class II: 2.57; pulpotomy: 3.60) were higher than those achieved using Simodont^® (class II: 1.97; pulpotomy: 2.92). Conclusions: Dental preparation scores were higher on acrylic teeth compared to the virtual simulation. While students reported a positive experience with Simodont^®, they expressed a preference for traditional learning methods involving acrylic teeth on phantoms or dental manikins.

Background: Wolf-Hirschhorn syndrome (WHS) is a rare disease caused by deletion in the distal moiety of the short arm of chromosome 4. The objectives of this study were to report the most representative oral findings of WHS, relate them with other clinical characteristics of the disease, and establish possible phenotype-genotype correlation. Methods: The study was conducted at 6 reference centers distributed throughout Spain during 2018–2019. The study group consisted of 31 patients with WHS who underwent a standardized oral examination. Due to behavioral reasons, imaging studies were performed on only 11 of the children 6 years of age or older. All participants had previously undergone a specific medical examination for WHS, during which anatomical, functional, epilepsy-related, and genetic variables were recorded. Results: The most prevalent oral manifestations were delayed tooth eruption (74.1%), bruxism (64.5%), dental agenesis (63.6%), micrognathia (60.0%), oligodontia (45.5%), and downturned corners of the mouth (32.3%). We detected strong correlation between psychomotor delay and oligodontia (p = 0.008; Cramér’s V coefficient, 0.75). The size of the deletion was correlated in a statistically significant manner with the presence of oligodontia (p = 0.009; point-biserial correlation coefficient, 0.75). Conclusion: Certain oral manifestations prevalent in WHS can form part of the syndrome’s phenotypic variability. A number of the characteristics of WHS, such as psychomotor delay and epilepsy, are correlated with oral findings such as oligodontia and bruxism. Although most genotype-phenotype correlations are currently unknown, most of them seem to be associated with larger deletions, suggesting that some oral-facial candidate genes might be outside the critical WHS region, indicating that WHS is a contiguous gene syndrome.

Background: Dentinogenesis imperfecta type I (DGI-I) is a hereditary alteration of dentin associated with osteogenesis imperfecta (OI). Aim: To describe and study the morphological characteristics of DGI-I with scanning electron microscopy (SEM). Material and methods: Twenty-five teeth from 17 individuals diagnosed with OI and 30 control samples were studied with SEM at the level of the enamel, dentin–enamel junction (DEJ) and four levels of the dentin, studying its relationship with clinical–radiographic alterations. The variables were analysed using Fisher’s exact test, with a confidence level of 95% and asymptotic significance. Results: OI teeth showed alterations in the prismatic structure in 56%, interruption of the union in the enamel and dentin in 64% and alterations in the tubular structure in all of the cases. There is a relationship between the severity of OI and the morphological alteration of the dentin in the superficial (p = 0.019) and pulpar dentin (p 0.004) regions. Conclusions: Morphological alterations of the tooth structure are found in OI samples in the enamel, DEJ and dentin in all teeth regardless of the presence of clinical–radiographic alterations. Dentin structural anomalies and clinical dental alterations were observed more frequently in samples from subjects with a more severe phenotype of OI.

Occlusion is the way in which the dental arches are related to each other and depends on craniofacial growth and development. It is affected in patients with Osteogenesis Imperfecta (OI) who present altered craniofacial development. The malocclusion present in 49 patients diagnosed with different types of OI aged between 4 and 18 was studied. The control group of healthy people was matched for age, sex, and molar class. To study the mixed and permanent dentition, the American Board of Orthodontics (ABO) discrepancy Index was applied. The primary dentition was evaluated with a Temporary Dentition Occlusion Analysis proposed for this study. The OI group obtained higher scores in the Discrepancy Index than the control group, indicating a high difficulty of treatment. The most significant differences were found in types III and IV of the disease. Regarding the variables studied, the greatest differences were found in the presence of lateral open bite in patients with OI, and in the variable “others” (agenesis and ectopic eruption). The analysis of primary dentition did not show significant differences between the OI and control groups. Patients with OI have more severe malocclusions than their healthy peers. Malocclusion is related to the severity of the disease and may progress with age.

Osteogenesis imperfecta (OI) is a hereditary bone fragility disorder that in most patients is caused by mutations affecting collagen type I. Their typical oral and craneofacial characteristics (Dentinogenesis imperfecta type I and class III malocclusion), involve the dentist in the multidisciplinary team that treat these patients. It is usual to perform lateral skull radiographs for the orthodontic diagnosis. In addition, this radiograph is useful to analyse the junctional area between skull base and spine, that could be damaged in OI. Pathology in the craneovertebral junction (CVJ) is a serious complication of OI with a prevalence ranging from rare to 37%. To diagnosis early skull base anomalies in these patients, previously the neurological symptoms have been appear, we make a simple cephalometric analysis of the CVJ. This method has four measurements and one angle. Once we calculate the values of the OI patient, we compare the result with the mean and the standard deviations of an age-appropriate average in healthy controls. If the patient has a result more than 2,5 SDs above the age-appropriate average in healthy controls, we should to refer the patient to his/her pediatrician or neurologist. These doctors have to consider acquiring another diagnostic images to be used to determine cranial base measurements with more reliability. Thereby, dentists who treat these patients, must be aware of the normal radiological anatomy of the cervical spine on the lateral cephalogram. Key words:Osteogenesis imperfecta, craniovertebral junction, cephalometric.