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Purpose: Altering the tooth morphology is a frequent clinical situation and it requires replacing the lost tooth substance by direct/indirect treatment methods. The purpose of this study is to identify the optimal study group size to quantify the extent to which the change in dental morphology influences the amplitude and path of the mandibular movements at the condylar and dental level. Materials and Methods: The study was performed on 10 young participants, without associated joint pathology, with healthy complete dentition. The Zebris JMA System (Zebris Medical GmbH, Germany) condylograph were used. The condylar and occlusal parameters were registered, before and after the composite occlusal modification on the right first mandibular molar was made and data were synthesized as Excel Data. The SPSS2 software was used for statistical analyses, a descriptive analysis of the pair differences was performed, Kolmogorov-Smirnova and Shapiro-Wilk tests were applied to verify the normality, paired sample test for 0,05 level of significance and 80% power was applied to determine the proper sample size. Conclusion: The results show a change in movement parameters at both condylar and dental level: the sagittal motion of the condyle on both sides tends to have a more vertical trajectory, the incisal guidance in protrusion and the guidance in the lateral movement on the modified part are steeper, lateral movement guidance on the other side is shallower, a tendency of retrusion is noted in both condyles. Respecting original dental morphology is essential for functional harmonious integration of the restoration.

Graphical abstract, Introduction Obtaining a certain bone volume is an important goal in implantology or orthopedics. Thus, after tooth extraction, quite a lot of horizontal and vertical alveolar bone is lost in time and can be detrimental to the implant treatment outcome, while the treatment of critical bone defects is a considerable challenge for surgery. Objectives In this study we designed a new in vivo model as an useful experimental tool to assess guided bone regeneration (GBR) using a computer-aided design/manufacturing (CAD-CAM) space-maintaining barrier. Methods The barrier was 3D printed with three progressive heights, surgically placed on rat femur, and GBR results were analyzed at 2, 4, and 8 weeks by X-ray and bone mineral density analysis, histology/morphometry and by immunofluorescence and immunohistochemistry for osteogenesis and angiogenesis evaluation. Results The obtained results show that the proposed experimental model provides a real-time useful information on progressive bone tissue formation, which depends on the volume of isolated space created for GBR and on molecular events that lead to satisfactory vertical and horizontal bone augmentation and osteointegration. Conclusion In conclusion, the proposed customized three-dome space-maintaining barrier is suitable as an experimental tool to assess the potential of using the designed barriers in dentistry and orthopedics to promote the formation of new bone and determine their space- and time-dependent limitations. Meanwhile, guided bone augmentation for dentistry requires subsequent evaluation on an alveolar bone preclinical model followed by clinical implementation.

The prognosis of the prosthetic rehabilitation is linked to the proper transfer of the clinical data to the dental laboratory, in the digital or conventional workflow. The aim of the present study was to compare the dimensional accuracy of analog and digitalized models, focusing on the influence of impression polymeric materials on the final digital model. Methods: The master model with standard reference points and the three groups of test models, obtained by alginic acid polymer impression (group A) and condensation-cured poly(dimethyl siloxane) in two impression techniques (1-step putty/light-body-group 1T, 2-steps putty/ light-body-group 2T), were measured in four standardized points before and after digitization. The differences from the master model and between the pair analog and digital models was calculated and statistically analysed using Mann-Whitney tests (2 groups), and one-way Anova (3 groups) with post-hoc Tukey s Test was applied for pairwise analysis (a;=0.05). Results: All analog and digitalized model tests showed altered dimensions from the master model. A general reduction of the digitalized models, in sagittal and transversal dimensions, was observed, comparing to the reference model. The impression material was a significant factor influencing dimensional accuracy. Conclusions: a statistically significant difference was found between most of the models and the master model. However, through digitalization, some of the errors were compensated. The digital models from alginic acid polymer group (group A) registered the highest trueness, with no statistically significant difference (P]0.05) from the reference model.

Introduction. Peri-implantitis is a non-specific inflammation, induced or maintained in the host tissues. Peri-implantitis usually presents a succession of specific symptoms, such as: bleeding on palpation, mobility of the dental implant, pain, increased depth of the pockets located around dental implants. Purpose. Thus, in this material we wanted to carry out a review of the main notions, both theoretical and practical, which characterize the diseases of surrounding tissues of dental implant called peri-implantitis. Material and method. For this study, we used 31 practitioners from Bucharest who frequently perform implant-prosthetic rehabilitation treatments, based on a questionnaire consisting of 6 questions. Results and discussions. The doctors included in the study showed that they have a thorough training in the field of implant-prosthetic restorations and of course in the diagnosis and treatment of peri-implantitis. Conclusions. In-depth knowledge of the notions related to peri-implantitis leads to an early diagnosis, favoring the rapid application of a treatment that prevents the occurrence of subsequent complications.

Introduction. In the growing process of each individual, there are 4 essential stages that must be very well known by the pediatric dentist, when intervening on these changes: the stage named the age immediately after birth; pre-school age; the stage of mixed dentition and the age period after 12 years. Purpose. Starting from the existence of these 4 stages of the growing process of each individual, in this material we tried a brief presentation of some aspects, both theoretical and practical, regarding the therapeutic approach in the dental pathology of the temporary teeth. Material and method. The study was conducted through the collaboration of 35 dentists from all over the country based on a questionnaire consisting of 6 questions. Result and discussion. Following the application of the questionnaire we were able to create an image of the way in which the dental pathology of the permanent teeth is therapeutically approached by the practitioners included in the study. Conclusion. Dental lesions in the temporary dentition should be evaluated and treated with great care, to prevent the medium and long term complications of permanent dentition.

This age period after 12 years is characterized by an increase in all dimensions of all the anatomical structures of the individuals, under the influence of new factors that interfere with the general tonus of the body. Purpose. Thus, in this paper, we approached certain aspects of both theoretical and practical that may occur in the formation and development of dento-maxillary system in the age period of 12 years (after some authors, up to the age of 21 years). Material and method. The study was conducted between May 12 and June 25 2018 with the help of 55 dental practitioners. Results and discussions. The analysis of the answers provided by the participants in the study was performed by means of specific research methods. The results are eloquent and provide an overview of how dental practitioners manage the eruption of the wisdom tooth in the developmental processes of the dento-maxillary system. Conclusions. The eruption of the wisdom tooth is a certain element of growth, which must be taken into account in the future therapeutic approach of the morpho-functional imbalances of the dento-maxillary system.

Obtaining an extremely precise virtual model is decisive for the final success of prosthetic restorations on implants using CAD–CAM technology. Intraoral digital implant impression can be challenging under specific conditions (e.g., narrow spaces, lack of visibility, or subgingival margins) because sometimes the scan body does not reach an optimal supragingival level so that it can be scanned accurately. We propose an easy and quick solution, which uses an extraoral transfer device that requires minimum time and cost investment.

Objectives: The present study aims to identify the current level of clinical and technological performance of dental prosthetic rehabilitation on implants and the possible existence of correlations between different designs and occurring complications in Romanian practice. Material and method: An online questionnaire with 36 questions, grouped into five sections, has been designed using the Google Forms application. In 2019, it was approved by the Romanian Dental and Maxillofacial Prosthetic Society, and the link to the questionnaire was distributed via email to 70 members. The answers with multiple choice option were summarized in an Excel document, coded and statistically processed in the specific software (SPSS v20.0; IBM Corp). Fisher’s exact test, likelihood ratio and linearby- linear association were used, and pairs of two questions were tested considering a standard statistical significance p value=0.05. Results: The results show that screwed rehabilitations (80.5%) on platform switched (70.9%) bone level implant (76.4%) with multiunit (69.1%) abutments for fixed total prosthesis, and custom abutments (43.6%) for removable prosthesis are preferred in Romanian practice. Most common problems of fixed rehabilitation on implants are related to aesthetics (65.5%) and for overdenture to unscrewing (56.4%). Resin-polymerized material in the laboratory, acrylic teeth and milled metallic structure in both arches was the preferred design for fixed restauration in both arches. Multiple statistic significant correlations (p

The aim of the present study was to objectively assess the variability in color reproduction of metal-ceramic (MC) single crowns fabricated by blending different color of opaque and body ceramic in order to point out which shade of the ceramic layers influences mostly the final color of the restorations. Eight nickel-chromium ceramic metal alloy copings were fabricated, on the same cast, following by blending the ceramic for the specific A3 color as follows: one reference ceramic (R) was blended, according to the producer s recommendation, and seven tests crowns have been build-up by considering as variables each one of the two uniform opaque layers, and dentin layer. Color of each manufactured crowns was measured after the three important steps of the technological workflow: the last opaque layer, enamel-dentin correction and final glaze firing using Vita Easyshade spectrophotometer. The best final color match (color difference of deltaE=0.8) was obtained for specimen no. 5, with a lighter opaque firs layer (A1). Fabricated specimens of all groups, except for no.4, with a darker dentin layer (A 3.5), showed deltaE values between 0.8 and 2.8, in the limit of the threshold perception in the oral cavity, and were scored as good. Within the limits of the present study, we can conclude that the dentin-enamel layer mostly influences the final color of the MC crowns.

(1) Background: The success of prosthetic treatment with implant support depends on the combined effort of the team doctor-technician, each of them being responsible for the validation of execution stages. (2) Methods: we composed an online questionnaire with 18 multiple choice questions, using the Google Forms application. It was filled out by an equal number of prosthodontic specialists and dental technicians. Differences and associations were evaluated by Likelihood Ratio test, Linear by Linear association test, Kruskal-Wallis H test, Pearson Chi-Square test and the Fisher’s Exact test. (3) Results: Differences and similarities were found between the statements of prosthodontic specialists and dental technicians. Years of experience are correlated with the number of restorations, impression techniques and types of restoration (p ≤ 0.05). Similar answers for both groups were registered for preferred screw retained type of prosthetic abutment and most frequently reported complications. (4) Conclusions: The different perspectives of the two members of the prosthodontic team regarding the leading role in the treatment plan, type of abutment, impression technique and prosthetic design of implant fixed restorations has been revealed in our study. Similar education curricula and standards for continuing training courses after graduation are necessary for prosthodontic specialists and technicians in Romania.

(1) Background: Occlusal vertical dimension (OVD) in the optimal maxillo&ndash, mandibular relationship is an important parameter to establish when complex dental rehabilitation has to be done. The optimal method to measure OVD is still a challenge in everyday practice. The aim of the present study was to test the reliability of the correlation between OVD and some anthropometric and cephalometric methods described in the literature. The validity of OVD registration using a facial scanner was also assessed. (2) Materials and Methods: 150 dentate participants, aged 20&ndash, 25 years, were randomly selected using sealed envelopes. Anthropometric measurements between specific standard points were performed: Subnasion&ndash, Prementon (Sn&ndash, PM) and Subnasion&ndash, Gnation (Sn&ndash, Gn) in maximum intercuspation and in the rest mandibular position, right and left pupil to the corresponding chelion. The cephalometric measurements registered were the lower facial angle and the angle between mandibular and Frankfurt planes. The distance Sn&ndash, Gn in maximum intercuspation was compared to all other parameters. Facial scanning, with a mobile phone and installed dedicated application, was performed on ten subjects, randomly selected using the same method among the participants, and the obtained 3D files were analyzed. The digital measurements were compared, for validity, to the clinical measurements. Pearson&rsquo, s correlation coefficient was used, for comparing clinical Sn&ndash, Gn in maximum intercuspation position to the other parameters. (3) Results: A strong agreement between all measured anthropometric parameters of the facial scan and clinical contact measurement method was registered. None of the measured parameters could predict the exact OVD. (4) Conclusions: In the limits of our study, the facial scanning could be used for predictable registration of OVD and the stored digital information could be preserved through life and use for oral rehabilitation. However, if OVD needs to be determined, several measurement methods, including cephalometric measurements, need to be used simultaneously to reach a final decision.

The procedure described provides a novel and accessible virtual facebow transfer based on standardized photographs loaded in the virtual articulator module of a computer-assisted design and computer-assisted manufacturing (CAD-CAM) software program for dental applications. The practical application of the technique in a digital workflow is the correct alignment of the digital maxillary cast to the virtual articulator with respect to the patient's planes and the skin markings of the condylar axis.

Association between tooth morphology, occlusal relations and mandibular condyle/glenoid fossa morphology is still a controversial issue in dentistry. The aim of the present study was to examine the influence of three important articular parameters on the dental morphology and the crown volume, quantifying the variation for each tooth group: incisor, canine, premolar and molar. Materials and methods All maxillary teeth from a set of basic study models were prepared for zirconia single crowns. The models were scanned and then, using a computer aided design software, they were mounted in a virtual articulator and specific mandibular movements were defined. The crown morphology was designed and statically adapted. Ten models were obtained by dynamical adjustment of the basic model for successively modified articular parameters: sagittal condylar inclination (SCI) = 30°, Bennett angle (BA) = 10°, Immediate side shift (ISS) = 0.5 mm — for control and SCI: 40°, 50° and 60° with BA and ISS as control, BA: 15°, 20° and 25° with SCI and ISS as control, ISS: 1.5 mm, 1.0 mm and 0.0 mm with SCI and BA as control — for the nine test models. The following measurements were performed three times on the right side of each model: volume for each tooth group, slope (S) for the central incisor, S and mesio-distal angle (MDA) for canine, S, MDA and vestibulo-oral angle (VOA) for the first premolar and molar. Results When SCI was varied, statistically significant changes as compared to the controls were found for incisor’s and premolar’s S, premolar’s VOA and, for 50° and 60°, MDA and molar’s MDA (for 50°) and VOA (for 60°). When BA was varied, significant changes were found for S (canine) and, in certain models, MDA (premolar, molar). Variations of ISS significantly changed mainly MDA for molars and, in two models, premolars. Conclusions Within the limits of this study, among the articular parameters, SCI mostly influenced the dynamic tooth morphology, but canine and molar morphology was stronger influenced by BA and/or ISS.

The study aims at obtaining an aesthetic preview in complex prosthetic restorations for elderly patients. Ten elderly patients were selected for this study; an extra-and intra-oral set of photographs is performed for each patient and edited with available software. Additionally, a series of standardized photos of the head is made using a new method to collect and process them with special software packages. Processed 2D digital photographs and tridimensional personalized models are obtained and a comparison between the two categories of data is made. Compared to the bi-dimensional planning, the 3D aesthetic preview offers better possibilities and it proves to be a useful instrument in aesthetic diagnosis and treatment, in increasing the patients acceptance of the final results. Tridimensional computerized personalized model allows building up a valuable preview in prosthetic reconstruction for elderly patients.