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Within the field of tissue engineering, natural tissues are reconstructed by combining growth factors, stem cells, and different biomaterials to serve as a scaffold for novel tissue growth. As adequate vascularization and innervation are essential components for the viability of regenerated tissues, there is a high need for easily accessible stem cells that are capable of supporting these functions. Within the human tooth and its surrounding tissues, different stem cell populations can be distinguished, such as dental pulp stem cells, stem cells from human deciduous teeth, stem cells from the apical papilla, dental follicle stem cells, and periodontal ligament stem cells. Given their straightforward and relatively easy isolation from extracted third molars, dental stem cells (DSCs) have become an attractive source of mesenchymal-like stem cells. Over the past decade, there have been numerous studies supporting the angiogenic, neuroprotective, and neurotrophic effects of the DSC secretome. Together with their ability to differentiate into endothelial cells and neural cell types, this makes DSCs suitable candidates for dental tissue engineering and nerve injury repair.

Stroke is the second most common cause of death and is a major cause of permanent disability. Given the current demographic trend of an ageing population and associated increased risk, the prevalence of and socioeconomic burden caused by stroke will continue to rise. Current therapies are unable to sufficiently ameliorate the disease outcome and are not applicable to all patients. Therefore, strategies such as cell-based therapies with mesenchymal stem cell (MSC) or induced pluripotent stem cell (iPSC) pave the way for new treatment options for stroke. These cells showed great preclinical promise despite the fact that the precise mechanism of action and the optimal administration route are unknown. To gain dynamic insights into the underlying repair processes after stem cell engraftment, noninvasive imaging modalities were developed to provide detailed spatial and functional information on the donor cell fate and host microenvironment. This review will focus on MSCs and iPSCs as types of widely used stem cell sources in current (bio)medical research and compare their efficacy and potential to ameliorate the disease outcome in animal stroke models. In addition, novel noninvasive imaging strategies allowing temporospatial in vivo tracking of transplanted cells and coinciding evaluation of neuronal repair following stroke will be discussed. Esther Wolfs, Jessica Ratajczak, Tim Vangansewinkel, Petra Hilkens, and Annelies Bronckaers are funded by Fonds Wetenschappelijk Onderzoek by grants G0A7514N, G089213N, G029112N, 12D8516N, and 1508015N, respectively. Yorg Dillen is funded by Bijzonder On- ¨ derzoeksfonds by grant BOF15DOC04.

The aim of this article is to report the clinical case of a right subcondylar fracture in a 4-year-old boy. The displaced and medial angulated fragmented mandibular condyle in coexistence with an enlarged lateral pterygoid process was compressing the inferior alveolar nerve (IAN) during its course in the area of the infratemporal fossa. This was expressed by exhibiting a rubbing behavior with resulting superficial ulceration at the right lower lip. Hypoesthesia of the lower lip may be a sign of the IAN entrapment after a subcondylar fracture in a child. In contrast to the adults where an open reduction is necessary to relieve the symptoms of hypoesthesia, in pediatric population, a conservative approach seems sufficient.

OBJECTIVES To systematically review the available literature on the influence of dental implant placement and loading protocols on peri-implant innervation. MATERIAL AND METHODS The database MEDLINE, Cochrane, EMBASE, Web of Science, LILACS, OpenGrey and hand searching were used to identify the studies published up to July 2013, with a populations, exposures and outcomes (PEO) search strategy using MeSH keywords, focusing on the question: Is there, and if so, what is the effect of time between tooth extraction and implant placement or implant loading on neural fibre content in the peri-implant hard and soft tissues? RESULTS Of 683 titles retrieved based on the standardized search strategy, only 10 articles fulfilled the inclusion criteria, five evaluating the innervation of peri-implant epithelium, five elucidating the sensory function in peri-implant bone. Three included studies were considered having a methodology of medium quality and the rest were at low quality. All those papers reported a sensory innervation around osseointegrated implants, either in the bone-implant interface or peri-implant epithelium, which expressed a particular innervation pattern. Compared to unloaded implants or extraction sites without implantation, a significant higher density of nerve fibres around loaded dental implants was confirmed. CONCLUSIONS To date, the published literature describes peri-implant innervation with a distinct pattern in hard and soft tissues. Implant loading seems to increase the density of nerve fibres in peri-implant tissues, with insufficient evidence to distinguish between the innervation patterns following immediate and delayed implant placement and loading protocols. Variability in study design and loading protocols across the literature and a high risk of bias in the studies included may contribute to this inconsistency, revealing the need for more uniformity in reporting, randomized controlled trials, longer observation periods and standardization of protocols.

Enkele minder bekende morfologische eigenschappen en detail-structuren van het Proximale Interphalangeale (PIP-) gewricht van de normale vinger worden besproken, die een rol zouden kunnen spelen bij de pathogenese van reumatoïde artritis. Naast het verloop van de capillairen in het gewrichtskapsel, en het gekruiste, laagsgewijze verloop van de vezelbundels in het proprius collateraal ligament (PCL) van het PIP-gewricht, spreken vooral de intra-articulaire plicae synoviales (synovial folds), en de in het PCL aanwezige gelamelleerde proprioceptieve lichaampjes tot de verbeelding. Ideeën worden geopperd omtrent mogelijke microtraumata van deze structuren. Recente literatuurgegevens suggereren namelijk het pathogenetisch belang van zulke microtraumata, die ook aanleiding kunnen zijn tot chronische gewrichtsontstekingen zoals reumatoïde artritis waarvan de (vroege) symptomen immers vaak de hand betreffen, met name de PIP-gewrichten.

This study offers data on finger joint morphology, revealed by micro-anatomical observations, histological screening, and various high resolution imaging techniques in in-vitro anatomical specimens of small finger joints. Such data may help to understand the use of finger joints while handling PC mice, especially flexing and extending the fingers in e.g. moving a PC mouse scrolling wheel during educational and professional activities. Possible solutions after long standing finger problems are proposed.

Purpose: Left ventricular (LV) twist and untwist rate (UR) are known to be strongly related to LV systolic and diastolic function, respectively. Although these parameters are emerging as important tools to evaluate LV function, yet their assessment and physiological significance in small animals remain challenging. The study was designed to investigate how twist and UR, measured by speckle tracking imaging (STI), relate to LV function and extent of fibrosis in a rat model of chronic myocardial infarction (MI). Methods: 23 Sprague-Dawley rats were subjected to LAD ligation (MI; n=14) or sham surgery (SHAM; n=9). 2D echocardiography at baseline (BL), day 1, day 3 and 2 months post-surgery was used to calculate LV dimensions, volumes (EDV, ESV) and global functional parameters. STI was applied to measure circumferential strain (Scirc), twist and UR. LV fibrosis was estimated from Sirius Red staining at day 1, day 3 and 2 months post-surgery. Results: Progressive cardiac failure evaluated during 2 months was characterized by a gradual increase in EDV and ESV respectively (0.2±0.04 mL to 0.8±0.2mL, and 0.04±0.02mL to 0.5±0.1 from BL to 2 months post-surgery, p

In the PIP joint capsule of the finger, neurofilaments and lamellated corpuscules are observed, comparable with those present in human facet joints. Our study demonstrated these corpuscules in the PIP Proper Collateral Ligament for the first time. Supposedly acting as mechanoreceptors, they may also produce cytokines and substance P, a neuropeptide involved in pain. As the PIP joints of fingers in particular show symptoms of Rheumatoid Arthritis at very early stages, these organs may therefore play a role in the pathogenesis of Rheumatoid Arthritis.

In conclusion, we state that curiosity-driven research after normal synovial folds within the PIP-joint of the finger confirms their actual location. Neurovascular bundles in the normal PIP-joint’s capsule, and neurons in lamellated corpuscles within the Proper Collateral Ligament, may shed new light on the pathogenesis of rheumatoid arthritis in human finger joints.

The bony attachments of the PIP (proximal interphalangeal) joint's collateral ligaments of the finger, are known as the so-called entheses. Enthesitis as a key-mechanism in human arthritis was investigated by various authors (e.g., McGonagle et al., 2003). Therefore we carried out a meticulous morphological reappraisal, based on coronal HR-MRI slices of a normal anatomical specimen of an extended PIP joint (Lippens et al. , 1997). Additional coronal histological sections (Masson Trichrome & Weigert Orcein staining) of a PIP collateral ligament from a normal finger anatomical specimen, observed under low power magnification, reveal crisscrossing of collagen fiber bundles with virtually no elasticity. This contrasts with the simple parallelism of collagen fibers as sketched in the diagrams from literature.

Objective: Current available therapies are unable to adequately promote functional recovery in patients suffering from neurological disorders such as stroke, which are a major cause of death and permanent disability. As an alternative treatment, cell-based therapies are now emerging. Human neural stem cells are the most promising candidates to induce neuronal repair, but due to ethical and practical considerations, alternative sources of progenitor cells with neuronal differentiation potential are needed. The aim of the present study was to differentiate stem cells that were isolated from the human dental pulp (hDPSCs) towards functionally active neuronal cells in vitro. Methods: hDPSCs were subjected to a two-step protocol. First, neurosphere-formation was used to acquire neuronal induction. Secondly, neuronal maturation was induced, based on cAMP and NT-3 signaling. The ultrastructural characteristics of intra-neurospheral hDPSCs and their microenvironment were determined by means of transmission electron microscopy (TEM). Neurogenic maturated hDPSCs (d-hDPSCs) were subjected to immunocytochemical, PCR, ultrastructural and electrophysiological analysis. An Enzyme-Linked Immunosorbent Assay (ELISA) was performed for VEGF, NGF, BDNF and GDNF in order to evaluate the secretome of hDPSCs before and after neurogenic differentiation. Results: Based on the ultrastructural analysis it was shown that within the neurospheres, intercellular communication was promoted. Moreover, hDPSCs grew out of the neurospheres in vitro and established a neurogenic differentiated hDPSC culture (d-hDPSCs) which was characterized by the increased expression of the neuronal markers NeuN, MAP-2 and NCAM compared to the nondifferentiated counterpart. Moreover, the secretion of BDNF, VEGF and NGF differed between dhDPSCs and hDPSCSs. Ultrastructurally, d-hDPSCs acquired neuronal features including multiple intercommunicating cytoplasmic extensions and increased vesicular transport. Finally, patch clamp analysis demonstrated the functional activity of d-hDPSCs by the presence of TTX-sensitive voltagegated sodium and TEA-sensitive potassium channels. A subset of d-hDPSCs was able to fire a single action potential. Conclusions: Although promising results were achieved, establishing a completely functional dhDPSC culture remains a challenge. The results in this study demonstrate that hDPSCs are capable of neuronal commitment with distinct features of neuronal cells.

Starting from analyses, performed to design total knee joint prostheses, we used similar approaches for the proximal interphalangeal (PIP) joint of the finger (Wachowski et al., 2011). By 4-bar linkage analysis of main fiber bundles in the PIP joint´s Proper Collateral Ligament (PCL), we were able to construct the curvatures of the only two articulating surfaces which can perform PIP flexion by rolling relative to each other without any gliding. Such engineering results can be used for prosthesis design although they deviate from normal anatomy. Endorsed by HandShoemouse ® ("Hippus") the Truly Ergonomic Computer Mouse - see http://www.handshoemouse.com/

Management of the ranula is controversial. There are several different options, each with advantages and disadvantages. A retrospective patient file analysis of 35 cases treated in our hospital showed that excision of the ipsilateral sublingual gland with ranula excission (true cyst) or with evacuation of the ranula (pseudocyst) is first choice treatment for oral and plunging ranula.

Superficial and deep fiber bundles within the proper collateral ligament (PCL) of the finger's Proximal Inter Phalangeal (P.I.P.) joint(van Zwieten et al., 2011)are clearly visible in High Resolution MRI frontal and sagittal slices. Because these bundles are fully tautened during PIP flexion, and in view of their intercrossing, we could conceive the PIP joint as a crossed 4-bar linkage system. Introducing into this 4-bar linkage model numerical values, obtained after measurements in sagittal HR-MRI slices, allowed us to construct the curvatures of the only two articulating surfaces which can perform PIP flexion by rolling relative to each other without any gliding. Endorsed by "Hippus Handshoemouse" - Truly Ergonomic Mouse, the only PC-mouse that fits like a glove, www.handshoemouse.com/