This study investigated the distribution and magnitude of stress generated in the enamel of an upper first premolar, after applying normal and excessive occlusal loads in a vertical and horizontal direction, using Finite Element Analysis (FEA). Methodology: A 3D virtual model of an upper first premolar was analyzed. The CT images of the tooth were converted into 3D data using the program MIMICS and Finite Element Analysis (FEA) was used for the stress study. To better understand the distribution of stress generated by occlusal loading, the situation of the enamel in various 3D virtual models was presented. 14 scenarios for the occlusal loading of the virtual models of the upper first premolar were obtained and the areas with the highest concentration of stress were emphasized. Results: In the model with the tooth intact, stress values were higher than the admissible ones in the simulation of the excessive vertical loading, normal horizontal loading and excessive horizontal loading. Stress was found in the buccal cusp area and in the cervical area, mainly on the buccal side of the tooth. In the models with horizontal occlusal tooth wear, stress values were higher than the admissible ones in the simulation of the excessive vertical loading. Stress was found in the cervical area. In the models with oblique occlusal tooth wear, stress values were higher than the admissible ones in the simulation of the normal and excessive horizontal loading. Stress was found mainly in cervical area, on the buccal side of the tooth. Conclusions: The most harmful loads were the heavy vertical ones and the horizontal ones, no matter the magnitude.

The implementation of CAD-CAM systems in dentistry has significantly influenced the evolution of dental implantology and implant-supported prosthetics within the past three decades. Implant-supported prostheses are comfortable and aesthetic. The prosthetic abutment has also faced a rapid design evolution, from the individualization of standard stock abutments offered by various manufacturers to a modern customization process using CAD-CAM technology. This paper presents a comparative study between 20 dental custom CAD-CAM implant abutments and 20 dental implant stock abutments, based on a set of measurements performed on the digital casts obtained from 24 cases of prosthetic rehabilitation on implants. The statistical analysis (Mann–Whitney U test) revealed significant differences between these two types of abutments: the incisal margin line diameter dimensions for custom abutments were significantly improved compared to standard abutments at the cervical level (U = 343.00, z = 3.868, p < 0.0005) and the incisal/occlusal level (U = 352.00, z = 4.112, p < 0.0005), while the inclination angle of the custom abutments relative to the 0-axis was significantly smaller than that of standard abutments (U = 115.50, z = −2.286, p = 0.022). The use of custom abutments leads to an increase in the final size of the abutment, an improvement in the retention of the prosthetic work, and reduces the angulation of the abutment in relation to the implant axis, thus decreasing the risk of unscrewing or fracturing the dental screw.

Background: Developmental defects of enamel (DDE) are frequently encountered in primary and permanent teeth, yet their etiology is not completely known. Enamel hypoplasia is considered a predisposing factor for early caries. The objective of this study was the evaluation of several risk factors potentially causing DDE and the possible association between DDE and dental caries. Methods: This study was performed on a group of 213 rural children from Romania. It combined a thorough dental examination for all children, and a questionnaire filled in by their mothers, regarding the evolution of their pregnancy and the child’s health status in the first years of life. Results: There was no statistically significant association between DDE presence and data regarding the evolution of pregnancy, mothers’ health status or children’s conditions during early childhood. There was a significant association between the use of amoxicillin, ibuprofen, and cephalosporin during the period of formation of permanent teeth, and one environmental factor (water source), and the presence of DDE (Chi Square, p < 0.05). Also, DDEs were associated with the presence of caries (Fisher, p = 0.001). Conclusions: Children who consumed water from private wells and children who received medication during early childhood developed more enamel defects, presenting a higher risk of caries development.

The aim of this study was the evaluation of the long term results in the clinical applicability of two root canal sealers, Sealapex Xpress - Kerr Endodontics (non-eugenol, calcium hydroxide polymeric root canal sealant) and AH Plus Jet - Dentsply Maillefer (epoxy resin-based sealant). 225 teeth of 159 patients included in this study, were endodontic treated and filled with the previously mentioned root canal sealers, in accordance with a standard clinical protocol. The long term results regarding the evaluation of the used two root sealers were realized clinically and radiologically, after annually monitoring conducted during three years. Long-term results of the study showed that, although their different chemical composition, the two root filling material showed good results in the treatment of various types of endodontic disease.

Sucking the thumb is considered an inborn reflex. However, after the age of four (in case of emotional instability and anxiety) this reflex becomes a bad habit. This vicious habit is one of the most important etiological factors which determine the Angle Class II/1 malocclusion. The research relied on the analysis of the photos of schoolchildren aged 6 to 14 who admitted the persistence of this bad habit and also had Angle Class II/1 malocclusions. We analysed the photos of the face and of the exobuccal and endobuccal profiles. We have chosen two cases from the researched group to highlight the clinical aspects of Angle Class II/1 malocclusions. The patients maintained the bad habit of sucking the thumb which, accompanied by other etiological factors, led to a skeletal disequilibrium. Thus, many modifications may appear such as: upper jaw prognathism and lower jaw retrognathism with a sagittal inocclusion as well as changes of the physiognomy specific to Angle Class II/1 malocclusions. In the case of Angle Class II/1 malocclusions, the coexistence of hereditary and functional pathologic factors generally leads to skeletal and neuro-muscular modifications with aesthetic repercussions.