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Objective: We aimed to find morphological properties of the hyoid bone, which are predominant among the patients diagnosed with obstructive sleep apnoea (OSA), and compare them with healthy individuals. Methods: A total of 67 cone-beam computed tomography (CBCT) image sequences of patients (44 males, 23 females) diagnosed with OSA and a total of 70 multislice computed tomography (MSCT) data of non-OSA patients (45 males, 25 females) were selected in this study. DICOM images were imported into InVivo 5.1.2 (Anatomage) software. The position of the hyoid bone relative to the C3 and C4 cervical vertebrae, as well as its morphological type (B, V, U, H, D, HK-type) and its total volume was determined. Results: The volumetric values of the hyoid bone of OSA patients (2384.49 ± 682.073 mm3) were significantly (P 3). The difference was independent of gender, and volumetric values showed a strong significant (P 3) and female OSA and non-OSA patients (1763 ± 242.51 2584; 2584.12 ± 840.21 mm3), as well. In the case of B and V-types, the volumetric values showed significant differences (P 3) and non-OSA patients were compared (2823,48 ± 780; 3216 ± 463 mm3). Conclusion: Our results suggest that the volume of the hyoid bone might be a potential biological marker for OSA, especially in the case of B and V hyoid bone types.

Objectives. Functional tooth replacement and bone regeneration are parts of the daily practice in modern dentistry, but well-reproducible and relatively inexpensive experimental models are still missing. We aimed to develop a new small animal model to monitor osseointegration utilizing the combination of multiple evaluation protocols.Material and methods. After cutting the tail between the C4 and C5 vertebrae in Wistar rats, costume made, parallel walled, non-threaded implants were placed into the center of the tail parallel with its longitudinal axis using a surgical guide. Osseointegration of the titanium implants was followed between 4 and 16 weeks after surgery applying axial extraction force, and resonance frequency analysis as functional tests, and histomorphometry and micro-CT as structural evaluations.Results. In functional tests, we observed that both methods are suitable for the detection of the time-dependent increase in osseointegration, but the sensitivity of the pull-out technique (an approximately five times increase with rather low standard error) was much higher than that of the resonance frequency analysis. In structural evaluations, changes in the detected bone implant contact values measured by histomorphometry (yielding 1.5 times increase, with low variations of data) were more reliable than micro-CT based evaluations to screen the developments of contact between bone and implant.Conclusion. Our results provide evidence that the caudal vertebrae osseointegration model is useful for the preclinical evaluation of implant integration into the bone.Clinical relevance. The combination of the biomechanical and structural tests offers a well-reproducible small animal system that can be suitable for studying the integration of various implant materials and surface treatments.

Serum albumin‐coated bone allografts (BoneAlbumin) have successfully supported bone regeneration in various experimental models by activating endogenous progenitors. However, the effect of tissue aging, linked to declining stem cell function, has yet to be explicitly examined within the context of BoneAlbumin's regenerative capacity. Stem cell function was tested with an in vitro attachment assay, which showed that albumin coating increases stem cell attachment on demineralized bone surfaces in an aging cell population. Bone regeneration was investigated in vivo by creating critical size bone defects on the parietal bones of aging female rats. Demineralized bone matrices with and without serum albumin coating were used to fill the defects. Bone regeneration was determined by measuring the density and the size of the remaining bone defect with computed tomography (CT). Microcomputed tomography (MicroCT) and mechanical testing were performed on the parietal bone explants. In vivo CT and ex vivo microCT measurements showed better regeneration with albumin‐coated grafts. Additionally, the albumin‐coated group showed a twofold increase in peak fracture force compared with uncoated allografts. In the present study, serum albumin‐coated demineralized bone matrices successfully supported faster and functionally superior bone regeneration in aging rats. Because stem cell function, a key contributor of bone remodelling, decreases with age and serum albumin is an effective activator of endogenous progenitor cells, this method could be an effective and safe adjuvant in bone regeneration of aging adult and osteo‐compromised populations.

The aim of this study was to compare the microarchitecture of augmented bone following maxillary sinus augmentation (MSA) after healing periods of 3 (test) and 6 (control) months using the combination of advanced platelet-rich fibrin (A-PRF) and a serum albumin-coated bone allograft (SACBA). Twenty-six patients with 30 surgical sites who required two-stage MSA were enrolled and grafted with the combination of A-PRF and SACBAs. The surgical sites were randomly allocated to the test or control group. During implant site preparation, 17 bone core biopsy samples were collected from each study group for histological, histomorphometric and micromorphometric analysis. Resonance frequency analysis was performed at the time of implant placement and 6, 8, 10, and 12 weeks postoperatively. The percentage of newly formed bone was 44.89 ± 9.49% in the test group and 39.75 ± 8.15% in the control group (p = 0.100). The results of the µCT analysis showed no significant differences in morphometric parameters between the study groups. The implant stability quotient was not significantly different between the two groups at 10 and 12 weeks postoperatively. Based on these findings, the total treatment time may be reduced by 3 months with the use of A-PRF and SACBAs for two-stage MSA.

The purpose of our study was to compare micromorphometric data obtained by cone-beam computed-tomography (CBCT) and microcomputed-tomography (micro-CT) of the augmented sinus and to evaluate the long-term stability of the bone gain achieved using BoneAlbumin. Sinus lifts, and after 6-months, healing bone-biopsy and implant placement were carried out. Specimens were analyzed by micro-CT. A total of 16 samples were collected from nine patients (mean age 54.7 &plusmn, 6.5 years). Pre-, postoperative, and 3-year control CBCT-data were registered to determine from where the biopsy samples were harvested. Micromorphometric variables were calculated from the micro-CT- and CBCT-data, and their correlation was determined by Spearman's test. The volume of augmented bone was calculated at the time of implant placement and after 3 years. A positive correlation was found between bone-volume fraction, trabecular-separation, open-, and total-porosity, while a negative correlation was found between trabecular-thickness obtained from CBCT- and micro-CT-data (p &lt, 0.05). Mean volumetric reduction of 39.28% (11.88&ndash, 60.02%) was observed. Correlation of CBCT- and micro-CT-data suggested that micromorphometric analysis of CBCT reconstructions of the augmented sinuses provided reliable information on the microarchitecture of augmented bone. CBCT as a modality might be adequate in the analysis of bone quality in the augmented sinus. At the 3-year, control sinus grafts showed volumetric stability.

In this case report, we present the endodontic treatment and microsurgical intervention of dens invaginatus affecting a lateral incisor using cone-beam-computed tomography (CBCT). A 26-year-old woman visited us with a diagnosis of acute apical periodontitis in the upper right lateral incisor (tooth 12). Endodontic treatment of the tooth was carried out. Intraoral radiography provided limited information on the unusual anatomy of the pulp chamber and root canal system; therefore, preoperative CBCT was performed. At the 3-month recall, a radiograph revealed a 5-mm-diameter lateral transparency, and CBCT was, therefore, repeated to facilitate microsurgery treatment planning. A medical image-processing program was used to demonstrate the changes between the CBCT images obtained before and after root canal preparation. In conclusion, endodontic treatment of dens invaginatus is challenging even for endodontic specialists, because the therapy sometimes requires surgical intervention. The currently available novel three-dimensional imaging modalities may have importance in planning and following up the root canal treatment in such cases, especially when unforeseen complications arise.

A tanszékünkön megjelent 69 éves nőbeteg anamnézisének felvétele és stomato-onkológiai szűrése után panoráma(OP)felvétel készült, amelyen multiplex szklerotikus, cystosus felritkulások láthatók a mandibulán. A tapasztalt elváltozások alap-ján további képalkotó modalitások alkalmazása vált indokolttá, így posteroanterior (PA) és oldalirányú (LAT) koponya-, illetvecone beam CT (CBCT) felvételeket készítettünk. A PA és LAT koponyafelvételeken kóros eltérés a mandibulán kívül egyéb területen nem ábrázolódott. Minthogy a páciens ötéven belül nem jelent meg tüdőszűrő vizsgálaton, ezért nem rendelkezünk PA-mellkasfelvétellel. A páciens képanyaga alapján megerősítettük a fibrosus dysplasia radiológiai diagnózisát.

The key drawback of using demineralized bone matrix (DBM) is its low initial mechanical stability due to the severe depletion of mineral content. In the present study, we investigated the long-term regeneration of DBM in a critical size bone defect model and investigated the remineralization after 6 months. Bone defects were created in the cranium of male Wistar rats which were filled with DBM or left empty as negative control. In vivo bone formation was monitored with computed tomography after 11, 19, and 26 weeks postoperatively. After 6 months, parietal bones were subjected to micro-CT. Mineral content was determined with spectrophotometric analysis. After 11 weeks the DBM-filled bone defects were completely closed, while empty defects were still open. Density of the DBM-treated group increased significantly while the controls remained unchanged. Quantitative analysis by micro-CT confirmed the in vivo results, bone volume/tissue volume was significantly lower in the controls than in the DBM group. The demineralization procedure depleted the key minerals of the bone to a very low level. Six months after implantation Ca, P, Na, Mg, Zn, and Cr contents were completely restored to the normal level, while K, Sr, and Mn were only partially restored. The remineralization process of DBM is largely complete by the 6th month after implantation in terms of bone density, structure, and key mineral levels. Although DBM does not provide sufficient sources for any of these minerals, it induces a faster and more complete regeneration process. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1336-1342, 2016.

Blood serum fractions are hotly debated adjuvants in bone replacement therapies. In the present experiment, we coated demineralized bone matrices (DBM) with serum albumin and investigated stem cell attachment in vitro and bone formation in a rat calvaria defect model. In the in vitro experiments, we observed that significantly more cells adhere to the serum albumin coated DBMs at every time point. In vivo bone formation with albumin coated and uncoated DBM was monitored biweekly by computed tomography until 11 weeks postoperatively while empty defects served as controls. By the seventh week, the bone defect in the albumin group was almost completely closed (remaining defect 3.0 ± 2.3%), while uncoated DBM and unfilled control groups still had significant defects (uncoated: 40.2 ± 9.1%, control: 52.4 ± 8.9%). Higher density values were also observed in the albumin coated DBM group. In addition, the serum albumin enhanced group showed significantly higher volume of newly formed bone in the microCT analysis and produced significantly higher breaking force and stiffness compared to the uncoated grafts (peak breaking force: uncoated: 15.7 ± 4 N, albumin 46.1 ± 11 N). In conclusion, this investigation shows that implanting serum albumin coated DBM significantly reduces healing period in nonhealing defects and results in mechanically stronger bone. These results also support the idea that serum albumin coating provides a convenient milieu for stem cell function, and a much improved bone grafting success can be achieved without the use of exogenous stem cells.

Introduction The aim of this study was to compare the paranasal sinus volumes obtained by manual and semiautomatic imaging software programs using both CT and CBCT imaging. Methods 121 computed tomography (CT) and 119 cone beam computed tomography (CBCT) examinations were selected from the databases of the authors’ institutes. The Digital Imaging and Communications in Medicine (DICOM) images were imported into 3-dimensonal imaging software, in which hand mode and semiautomatic tracing methods were used to measure the volumes of both maxillary sinuses and the sphenoid sinus. The determined volumetric means were compared to previously published averages. Results Isometric CBCT-based volume determination results were closer to the real volume conditions, whereas the non-isometric CT-based volume measurements defined coherently lower volumes. By comparing the 2 volume measurement modes, the values gained from hand mode were closer to the literature data. Furthermore, CBCT-based image measurement results corresponded to the known averages. Conclusions Our results suggest that CBCT images provide reliable volumetric information that can be depended on for artificial organ construction, and which may aid the guidance of the operator prior to or during the intervention.

Socket preservation using a combination of porcine xenograft and collagen membrane maintains the vertical and horizontal dimensions of the ridge. The aim of this study was to evaluate the microarchitecture of the grafted area by histological analysis and micro-computed tomography. Patients in the test group (group 1; nine patients) underwent socket preservation, while the sockets in the control group (group 2; eight patients) were allowed to heal without preservation. After a 6-month healing period, bone core biopsy samples were obtained and implants were placed in the augmented sites in the test group (12 biopsy samples) and the non-augmented sockets of the control group (12 biopsy samples). Analysis of the biopsy samples obtained from group 1 revealed that particles of the graft were surrounded by newly formed bone in eight cases and by granulation tissue in four cases. Micromorphometric data showed statistically significant differences in several parameters between the microarchitecture of the native bone and the newly formed bone within the augmented sites, which suggests that the xenograft particles interfere with the bony healing of the alveoli.

Partitioning of polypeptides between protein folding and amyloid formation is of outstanding pathophysiological importance. Using yeast phosphoglycerate kinase as model, here we identify the features of the energy landscape that decide the fate of the protein: folding or amyloidogenesis. Structure formation was initiated from the acid-unfolded state, and monitored by fluorescence from 10 ms to 20 days. Solvent conditions were gradually shifted between folding and amyloidogenesis, and the properties of the energy landscape governing structure formation were reconstructed. A gradual transition of the energy landscape between folding and amyloid formation was observed. In the early steps of both folding and misfolding, the protein searches through a hierarchically structured energy landscape to form a molten globule in a few seconds. Depending on the conditions, this intermediate either folds to the native state in a few minutes, or forms amyloid fibers in several days. As conditions are changed from folding to misfolding, the barrier separating the molten globule and native states increases, although the barrier to the amyloid does not change. In the meantime, the native state also becomes more unstable and the amyloid more stable. We conclude that the lower region of the energy landscape determines the final protein structure.