Bálint Molnár

Simultaneous PKC and cAMP activation induces differentiation of human dental pulp stem cells into functionally active neurons

The plasticity of dental pulp stem cells (DPSCs) has been demonstrated by several studies showing that they appear to self-maintain through several passages, giving rise to a variety of cells. The aim of the present study was to differentiate DPSCs to mature neuronal cells showing functional evidence of voltage gated ion channel activities in vitro. First, DPSC cultures were seeded on poly-l-lysine coated surfaces and pretreated for 48h with a medium containing basic fibroblast growth factor and the demethylating agent 5-azacytidine. Then neural induction was performed by the simultaneous activation of protein kinase C and the cyclic adenosine monophosphate pathway. Finally, maturation of the induced cells was achieved by continuous treatment with neurotrophin-3, dibutyryl cyclic AMP, and other supplementary components. Non-induced DPSCs already expressed vimentin, nestin, N-tubulin, neurogenin-2 and neurofilament-M. The inductive treatment resulted in decreased vimentin, nestin, N-tubulin and increased neurogenin-2, neuron-specific enolase, neurofilament-M and glial fibrillary acidic protein expression. By the end of the maturation period, all investigated genes were expressed at higher levels than in undifferentiated controls except vimentin and nestin. Patch clamp analysis revealed the functional activity of both voltage-dependent sodium and potassium channels in the differentiated cells. Our results demonstrate that although most surviving cells show neuronal morphology and express neuronal markers, there is a functional heterogeneity among the differentiated cells obtained by the in vitro differentiation protocol described herein. Nevertheless, this study clearly indicates that the dental pulp contains a cell population that is capable of neural commitment by our three step neuroinductive protocol.

Treatment of multiple adjacent Miller Class I and II gingival recessions with collagen matrix and the modified coronally advanced tunnel technique

OBJECTIVE To clinically evaluate the treatment of Miller Class I and II multiple adjacent gingival recessions using the modified coronally advanced tunnel technique combined with a newly developed bioresorbable collagen matrix of porcine origin. METHOD AND MATERIALS Eight healthy patients exhibiting at least three multiple Miller Class I and II multiple adjacent gingival recessions (a total of 42 recessions) were consecutively treated by means of the modified coronally advanced tunnel technique and collagen matrix. The following clinical parameters were assessed at baseline and 12 months postoperatively: full mouth plaque score (FMPS), full mouth bleeding score (FMBS), probing depth (PD), recession depth (RD), recession width (RW), keratinized tissue thickness (KTT), and keratinized tissue width (KTW). The primary outcome variable was complete root coverage. RESULTS Neither allergic reactions nor soft tissue irritations or matrix exfoliations occurred. Postoperative pain and discomfort were reported to be low, and patient acceptance was generally high. At 12 months, complete root coverage was obtained in 2 out of the 8 patients and 30 of the 42 recessions (71%). CONCLUSION Within their limits, the present results indicate that treatment of Miller Class I and II multiple adjacent gingival recessions by means of the modified coronally advanced tunnel technique and collagen matrix may result in statistically and clinically significant complete root coverage. Further studies are warranted to evaluate the performance of collagen matrix compared with connective tissue grafts and other soft tissue grafts.

Recession Coverage Using Autogenous Grafts

Recreating natural pink esthetics around single or multiple recession defects require proper surgical planning and a careful choice of the grafting approach. The transplantation of free autogenous soft tissue grafts in combination with state-of-the-art surgical techniques for recession coverage still represents the gold standard in terms of long-term tissue stability. Donor site morbidity has to be considered prior to surgery; graft harvesting procedures should be well planned and executed to minimize postoperative patient complaints.

Analysis of blood supply in the hard palate and maxillary tuberosity—clinical implications for flap design and soft tissue graft harvesting (a human cadaver study)

ObjectivesThe aim of the present study is to provide a detailed macroscopic mapping of the palatal and tuberal blood supply applying anatomical methods and studying specific anastomoses to bridge the gap between basic structural and empirical clinical knowledge.Materials and methodsTen cadavers (three dentate, seven edentulous) have been prepared for this study in the Department of Anatomy, Semmelweis University, Budapest, Hungary, and in the Department of Anatomy of the Medical University of Graz. All cadavers were fixed with Thiel’s solution. For the macroscopic analysis of the blood vessels supplying the palatal mucosa, corrosion casting in four cadavers and latex milk injection in other six cadavers were performed.ResultsWe recorded major- and secondary branches of the greater palatine artery (GPA) and its relation to the palatine spine, different anastomoses with the nasopalatine artery (NPA), and lesser palatal artery (LPA) as well as with contralateral branches of the GPA. Penetrating intraosseous branches at the premolar-canine area were also detected. In edentulous patients, the GPA developed a curvy pathway in the premolar area. The blood supply around the maxillary tuberosity was also presented.ConclusionThe combination of different staining methods has shed light to findings with relevance to palatal blood supply, offering a powerful tool for the design and execution of surgical interventions involving the hard palate.Clinical relevanceThe present study provides clinicians with a good basis to understand the anatomical background of palatal and tuberal blood supply. This might enable clinicians to design optimized incision- and flap designs. As a result, the risk of intraoperative bleeding and postoperative wound healing complications related to impaired blood supply can be minimized.

Volumetric difference evaluation of registered three-dimensional preoperative and postoperative CT volumes

A methodology is presented for registering three-dimensional preoperative and postoperative CT scan volumes and for evaluating their differences in selected areas of interest. The proposed method was applied to CT cone beam data from ten patients in order to assess the volume of augmented bone in the alveolar region. A 3D affine model was used to align the preoperative and postoperative data. The differences between the aligned sets were assessed through subtraction radiography. The volume of the differences was finally evaluated by defining regions of interest in each slice of the subtracted 3D data. Both quantitative and qualitative results were obtained after applying the method to all sets. The effectiveness of the volumetric assessment algorithm was verified by applying the algorithm to an object of known volume.