Background/Objectives: This study investigates the etiology of enamel developmental defects, specifically Molar Incisor Hypomineralization (MIH), and explores correlations between MIH and dental anomalies such as hypodontia to improve interdisciplinary restorative and orthodontic treatments. Additionally, it assesses the influence of stress factors on the development of enamel defects. Methods: Conducted from July to September 2024, this study involved 57 patients aged 6 to 11 from an urban setting, divided into two groups: 32 with MIH and 25 controls, selected based on criteria of mixed dentition without systemic pathology or chronic medication. Clinical evaluations, including intraoral photographs and panoramic radiographs, were performed alongside a detailed questionnaire addressed to the mothers covering prenatal, perinatal, and postnatal factors. Results: The average age of children with MIH was 7.5 years, in contrast to 7.04 years in the control group (p = 0.17). Significant differences were noted in maternal age, with MIH mothers older (35.56 years) than controls (29.36, p = 0.0001). The prevalence of MIH was higher in boys (66.7%) compared to girls (38.1%, p = 0.036). Factors such as prolonged labor, medication during birth, and early postnatal medication were significantly linked to MIH. The study shows a strong correlation with hypodontia, with a significantly higher incidence of tooth number anomalies (p = 0.009) in the study group. Conclusions: Overall, the study emphasizes the association of MIH with various maternal and birth-related factors and with hypodontia, highlighting the need for a comprehensive, multidisciplinary approach to diagnosis and treatment. Further research is recommended to investigate the relationship between stress factors and MIH.

Introduction: The fundamental mechanical properties of 3D printed surgical guides used in orthodontics represent an important indicator for the accuracy of the insertion of skeletal anchorage devices. The tensile strength of devices printed by stereolithography (SLA) and digital light processing (DLP) methods, respectively, is influenced by factors such as finishing process. Aim of the study: This study illustrates a comparison of the tensile strength in two different types of 3D printed devices (SLA, DLP respectively) undergoing or not a standard process of polishing. Material and methods: Twenty-four specimens obtained according to ASTM D638-14 (Standard Test Method for Tensile Properties of Plastics) were used for the evaluation of tensile strength. Four groups of 6 samples from each category were created: SLA polished, SLA unpolished, DLP polished and DLP unpolished. After removing the support, finishing was performed to obtain smooth surfaces, according to the manufacturer’s recommendation. Type V specimen was used to perform tensile tests in accordance with the standard procedures ASTM D638-14 which recommends at least five specimens to be tested for each sample. One-way analysis of variance (ANOVA) and t-test showed statistically significant results at p < 0.05. SPSSv17 software was used for statistical analysis of the numerical variables, and also descriptive statistics were performed. Results: The measurements included: tensile strength (maximum load), tensile stress at maximum load and tensile strain at maximum load. The maximum load (tensile strength) of the polished specimens was lower, both for the SLA and DLP, with no statistical significance results. Conclusions: The conclusions indicated differences between maximum load and tensile stress at maximum load between polished and unpolished specimens, in both SLA and DLP groups. Althought the polishing process reduces the tensile strenght, the data analysis did not present statistically significant results.

Background/Objectives: Molar–incisor hypomineralization (MIH) is a prevalent dental condition characterized by hypomineralized enamel affecting the first permanent molars and incisors. It leads to visible enamel opacities, with varying severity. Children with MIH often experience dental hypersensitivity, which can result in increased dental fear and anxiety, complicating dental treatment. Salivary cortisol, a well-established biomarker of stress, has been used to assess stress levels in various pediatric conditions but has not been extensively studied in MIH. This study aimed to assess salivary cortisol levels as a stress biomarker in children with MIH and compare them to those in children without MIH. Methods: Sixty children aged 5–9 years were divided into two groups: 31 with MIH and 29 healthy controls. Salivary cortisol levels were measured using ELISA, and statistical analysis was performed using IBM SPSS software, version 23 The Mann–Whitney test was used for group comparison, and the Kruskal–Wallis test evaluated the correlation between MIH severity and cortisol levels. Results: Children with MIH showed significantly higher mean cortisol levels (2.63 ng/mL) compared to controls (0.96 ng/mL), with a p-value of 0.0001. A progressive increase in cortisol levels was observed with the severity of MIH, with the highest levels recorded in grade 3 (4.38 ng/mL), in contrast to grade 0 (0.95 ng/mL), with a p-value of 0.001. Conclusions: Salivary cortisol levels are significantly higher in children with MIH, suggesting that MIH-related stress may contribute to dental anxiety and hypersensitivity. These findings highlight the importance of stress management in pediatric dental care.

Introduction. It is well known that previously has been demonstrated a correlation between respiratory function and the harmonious craniofacial development and head posture respectively. Aim of the study. The purpose of this study was to investigate the correlation between rapid maxillary expansion (RME) and the change in natural head position (NHP) resulting from the consequent change in airway resistance and to elucidate how RME influences NHP in terms of cephalometric angles in children with nasal obstruction. Material and methods. The study included 12 girls and 8 boys who had a history of mouth breathing, as confirmed by the parents and ORL specialist and due to this fact, they underwent RME as part of orthodontic treatment. Dental casts, clinical photographs and lateral skull radiographs exposed in natural head position were obtained at the first visit (T1) and 8-10 months (T2) later for all subjects. In order to evaluate the patient’s lateral skull radiographs, I used AudaxCeph software, within which I created a new type of analysis. Student T test and Pearson correlation test were used to statistically analyze the results. Results. Our findings demonstrate that no significant changes in any of the variables are observed in patients treated with rapid maxillary expansion, however a positive correlation was observed in the variables measured before and after the treatment, respectively between the anomaly and the measured values. Positivity can also be detected when examining the correlation between the patient’s gender and the measured values. Conclusions. Based on the obtained results, we cannot state that there is a correlation between rapid maxillary expansion and cervical posture.