The aim of this study was to evaluate the effect of platelet-rich fibrin (PRF), placed in extraction sockets, on bone regeneration and orthodontic tooth movement in adolescents. Fourty extraction sockets from twenty patients requiring extraction of first premolars based on their orthodontic treatment plan participated in this split-mouth clinical trial. Immediately, the teeth adjacent to the defects were pulled together by a NiTi closed-coil spring with constant force. The bone regeneration and the amount of orthodontic tooth movement was evaluated.

Background and Objectives: Odontogenic sinusitis is a frequently underestimated pathology with fewer symptoms in patients with periapical lesions, periodontal disease, or iatrogenic foreign bodies in the maxillary sinus. The aim of our study was to determine the correlation between maxillary sinusitis and periapical lesions using cone-beam computed tomography (CBCT) imaging and histological and immunohistochemical investigations. Materials and Methods: A total of 1450 initial patients diagnosed with maxillary sinusitis in the Ear-Nose-Throat (ENT) Department, University of Medicine and Pharmacy “Grigore T. Popa” Iasi, Romania, were treated with anti-inflammatory drugs. Of these, 629 still had unresolved symptomatology and were later referred to the Dental Medicine departments for further investigations. Only 50 subjects with periapical lesions in the premolar/molar maxillary area were included in the present study. All the periapical lesions were observed on CBCT and classified using the Periapical Status Index (PSI) and the mean maxillary sinus mucosa thicknesses (MSMT). The enrolled patients underwent surgical procedures with the excision of periapical lesions. The excised samples were submitted to the histological and immunohistochemical investigations. Results: The 50 patients presented periapical lesions of their maxillary teeth in 328 dental units. There was a higher prevalence of periapical lesions in men than in women (chi-square test). We observed a significant difference between the mean MSMT of individuals with periapical lesions compared to those without (p < 0.01). Mean MSMT was 1.23 mm for teeth without periapical lesions and 3.95 mm for teeth with periapical lesions. The histopathological study identified 50% cases with periapical granulomas, 10% cases with periapical granulomas with cystic potential, and 40% cases as periapical cysts. Immunohistochemical stainings showed that CD4+ helper and CD8+ cytotoxic T lymphocytes, along with CD20+ B lymphocytes and CD68+ macrophages, were diffusely distributed in all periapical cysts and in some periapical granulomas, but CD79α+ plasma cells characterized especially periapical granulomas. Conclusions: The current study observed a significant correlation between CBCT maxillary mucosa thickness and type of periapical lesion. Chronic inflammatory lympho-histiocytic infiltrate predominates in periapical lesions, supporting the idea that lesion progression is determined by a humoral-type (CD20+ and CD79α+ B lymphocytes) but also by a cellular-type (CD4+ and CD8+ T lymphocyte population) immune mechanism.

In order to have an accurate impression, dimensional modifications must be under control throughout the impression stages, considering they are highly influenced by the variability level during polymerization.The factors with an influence on dimensional stability are:impression material width, tensile modulus, temperature during the imprinting process, storage humidity, the time lapse between imprinting and casting. The study focuses on dimensional modifications of varied elastic impression materials, considering both testing and impression techniques are done in similar conditions in order to assess accurately the behaviour of varied impression materials.Material and methods:The study was based on a laboratory simulation of a clinical situation. There were used two 6-year maxillary molars in the position they have in the oral cavity. A 3 mm wax layer was added during the next stage its width being checked with an Ivoclar mechanical vernier. The surface parallelism was subsequently checked using a parallelograph and there was taken an individual tray made of photopolymer acrylic. The measurements of this study were limited to the linear dimension, being observed the changes occurred in one direction, although contraction is a volumetric modification.The statistic assessment of the measurement data obtained in the case of the same type of addition silicon materials recorded an increase of the volumetric contraction type in dry environment and in longer time intervals.The addition materials were significantly superior in terms of contraction time, as compared to the previous case, granting higher accuracy to the end product. The Silagum Light presented an increased volumetric contraction in moist environment, the contraction being more significant in longer time intervals. The Xantopren L blue material has a reduced deformation gradient in less than 48 h.

Dentists and oral and maxillofacial radiologists have used periapical, occlusal, panoramic, and cephalometric radiographs for many years for diagnosing dental anomalies, especially before orthodontic or surgical treatment. Cone beam computed tomography was developed in recent years especially for the dental and maxillofacial region. Thus it has become the imaging modality of choice for many clinical situations, such as the assessment of dental impaction and structural teeth anomalies or other associated diseases and disorders (e.g., Gardner's syndrome, cleidocranial dysplasia). This article reviews different aspects of dental impaction and its possible effects on adjacent structures such as external root resorption, marginal bone loss, as well as describing structural dental anomalies. It provides a systematic analysis of their characteristic features and imaging findings for general radiologists to achieve a precise diagnosis and an optimal interpretation.

The aim of this study was to evaluate the diagnostic efficacy of the cone beam computed tomography (CBCT) - based mandibular indices and the CBCT mandibular bone density values and to determine whether they correlate with bone mineral density (BMD) of the lumbar spine (L1 - L4) and proximal left femur in patients with osteoporosis and diabetes mellitus, which were taken a treatment with strontium ranelate over a period of 6 months. The study included 20 osteoporosis patients and 40 diabetic patients (16 patients � type 1 diabetes mellitus and 24 patients � type 2 diabetes mellitus). In CBCT images, the radiomorphometric indices were measured in the right and left mandibles. The relationship between the CBCT measurements of the mandible and skeletal BMD was assessed. The present study showed that mandibular bone quality is closely correlated with the skeletal status of the patients with osteoporosis and diabetes mellitus which were in treatment with strontium ranelate for bone improving.