Dental Pulp Stem Cells on Implant Surface: An In Vitro Study.

In the field of biology and medicine, one hears often about stem cells and their potential. The dental implant new surfaces, subjected to specific treatments, perform better and allow for quicker healing times and better clinical performance. The purpose of this study is to evaluate from a biological point of view the interaction and cytotoxicity between stem cells derived from dental pulp (DPSCs) and titanium surfaces. Through the creation of complex cells/implant, this study is aimed at analyzing the cytotoxicity of dental implant surfaces (Myth (Maipek Manufacturer Industrial Care, Naples, Italy)) and the adhesion capacity of cells on them and at considering the essential factors for implant healing such as osteoinduction and vasculogenesis. These parameters are pointed out through histology (3D cell culture), immunofluorescence, proliferation assays, scanning electron microscopy, and PCR investigations. The results of the dental implant surface and its interaction with the DPSCs are encouraging, obtaining results increasing the mineralization of the tissues. The knowledge of this type of interaction, highlighting its chemical and biological features, is certainly also an excellent starting point for the development of even more performing surfaces for having better healing in the oral surgical procedures related to dental implant positioning.

Impacted Lower Third Molar Under Inferior Alveolar Canal: Technical Strategy for Minimally Invasive Extraoral Surgical Approach.

ABSTRACT: Ectopic lower third molar is an uncommon condition, and its etiology remains unclear. The main approach used for its surgical removal is the intraoral one, but there are cases in which this may not be the best option. When the lower third molar is located below the lower alveolar canal or when it is close to the lower edge of the jaw, the most recommended approach is the extraoral one. The critical issues related to the extraoral approach are the possibility of damaging anatomical structures such as marginal mandibular branch of the facial nerve (craniofacial nerve VII), facial artery and vein, and submental artery. This complication can occur during incision and dissection of the superficial layers or during osteotomy with rotating instruments.This paper reports a case of extraction of ectopic lower third molar using a minimally invasive extraoral approach combined with piezoelectric surgery in order to prevent intraoperative injury of anatomical structures.

Hereditary gingival fibromatosis associated with the missense mutation of the KCNK4 gene.

Hereditary gingival fibromatosis (HGF) is a rare oral condition that may appear as an isolated entity or as part of a genetic disease or syndrome. Molecular and biochemical mechanisms that trigger this pathologic process are not completely understood. In this article, we present a rare case of hereditary gingival fibromatosis in conjunction with a syndromic phenotype, associated with a rare missense mutation of the KCNK4 gene. This mutation induces a change in the structure of the TRAAK channel belonging to the 2-pore potassium channels. The gain of function promoted by the mutation could represent the pathogenetic basis of gingival fibromatosis.

Oral Health and Molecular Aspects of Malignant Fibrous Histiocytoma Patients: A Systematic Review of the Literature.

Malignant fibrous histiocytoma is one of the most common soft tissue sarcomas in adults. It occurs only occasionally in oral soft tissues, and knowledge about its characteristics is based on a limited number of cases reported in the literature. Malignant fibrous histiocytoma belongs to the group of soft tissue sarcomas and makes up less than 10% of soft tissue sarcomas. For therapeutic purposes, complete exeresis of the lesion (macroscopic and microscopic) is performed because they have frequent recurrences. As for complementary therapy in addition to surgery, neither radiotherapy nor chemotherapy have been shown to reduce the risk of death related to the disease. Often patients complain of a swelling that grows in a short period of time. It is quite common for patients to report trauma in the area, which is not the cause, but rather the event that allows diagnosis. The mass usually does not cause pain unless it compresses an adjacent nerve structure. The aim of this study is to systematically review the scientific literature in order to identify the most recent studies concerning malignant fibrous histiocytomas localized in oral soft tissues and report their main data. The main outcomes of this study concern the immunohistochemical, molecular, and clinical aspects of this pathology. A systematic review of articles in the electronic databases pubmed, Scopus, and Web of Science was performed. After the selection process, 11 studies met the inclusion criteria and were included in the review. The mean age of the patients was 50.8 years old. The lesions affected various parts of the oral cavity, showing predominantly storiform-pleomorphic patterns. All cases except one were treated with surgical resection and radiation therapy. Although some data emerged from this review, they remain limited to a few case reports. Further studies are necessary in order to standardize the approach to patients affected by oral malignant fibrous histiocytoma (MFH).

An unusual case of recurrent gingival hirsutism.

OBJECTIVES: The occurrence of hairs in the oral cavity is an exceedingly rare event, with unknown etiology. A literature review found only 5 cases, most of which described a single hair localized in various sites of the oral cavity. The aim of the present article is to report a follow-up presentation of a rare case of oral hirsutism detected in a young woman. CASE PRESENTATION: A 25-year-old woman with previously diagnosed polycystic ovary syndrome returned to our attention 6 years after the first intervention, complaining of the presence of oral hairs. Extraoral facial examination revealed the presence of exuberant hair on the chin and neck regions. Intraoral examination showed some brown hair, similar to eyelashes, which were removed and the underlying tissue histologically analyzed. One year later, the patient came back with even more widespread presence of oral hairs distributed on the gingivae of both arches. CONCLUSIONS: The occurrence of hairs in the oral cavity is an extremely rare finding. The etiology is still unknown; however, an investigation of systemic health is always desirable because more complex medical conditions may be present and not recognized.

Early Diagnosis on Oral and Potentially Oral Malignant Lesions: A Systematic Review on the VELscope® Fluorescence Method.

The fluorescence method is an innovative technique used by pathologists for examining body mucosa, and for the abnormalities tissue screening, potentially leading to the earlier discovery of pre-cancer, cancer or other disease processes. The early detection is one of the best mechanisms for enabling treatment success, increasing survival rates and maintaining a high quality of life. The purpose of this review is to evaluate the clinical efficiency of this diagnostic tool applied to the oral cavity (VELscope®). A literature systematic review has been performed. The initial research provided 53 results after applying the inclusion and exclusion criteria, and after a manual screening of the abstracts by the authors, only 25 results were eligible for review. The results and data contained in all the researches, no older than 10 years, were manually evaluated, and provided useful information on this diagnostic method. The VELscope® mean value about sensitivity and specificity resulted of 70.19% and 65.95%, respectively, by results analysis, but despite this some studies disagree about its clinical effectiveness, and this diagnostic method is still much debated in scientific and clinical medical literature. Surely being able to have efficient and effective tools from this point of view could help the clinician in the diagnosis, and also make timelier the pharmacological or surgical therapy, improving the quality of life of the patient, and in some cases guaranteeing a longer survival term.

Molecular Biomarkers Related to Oral Carcinoma: Clinical Trial Outcome Evaluation in a Literature Review.

BACKGROUNDS: The objective of the present research was to systematically revise the international literature about the genetic biomarkers related to oral cancer (OC) evaluating the recent findings in clinical studies. METHODS: A comprehensive review of the current literature was conducted according to the PRISMA guidelines by accessing the NCBI PubMed database. The authors conducted the search of articles in the English language published from 2008 to 2018. The present systematic review included only papers with significant results about correlation between wound healing, genetic alteration, and OC. Prognostic capacity of genetic markers was not evaluated in vivo. RESULTS: The first analysis with filters recorded about 1884 published papers. Beyond reading and consideration of suitability, only 20 and then 8 papers, with case report exclusion, were recorded for the revision. CONCLUSION: All the researches recorded the proteomic and genetic alterations in OC human biopsy cells. The gene modification level in the different studies, compared with samples of healthy tissues, has always been statistically significant, but it is not possible to associate publications with each other because each job is based on the measurement of different biomarkers and gene targets. Further investigations should be required in order to state scientific evidence about a clear advantage of using these biomarkers for diagnostic purpose.

Patient Discomfort During and After Surgically Assisted Rapid Maxillary Expansion Under Local Anaesthesia.

The aim of this study was to evaluate whether surgically assisted rapid maxillary expansion (SARME) could be performed under local anaesthesia and to understand the patient discomfort associated with this protocol. Patient discomfort was compared during and after 2 different types of oral surgical treatments in the same patients. Odontectomies for impacted lower third molar (control) were compared with SARME procedures (test) that were also performed under local anaesthesia. A visual analogic scale was used for each patient to quantify his or her discomfort before and after surgery. A total of 47 patients required 1 of these surgeries and were enrolled in this study. No statistically differences (P >0.05) were observed between the control and test groups. The results of this study suggest that SARME can be safely performed under local anesthesia because the intra- and postoperative discomfort levels were similar to those of other procedures that are typically performed under local anesthesia.

Extraoral surgical approach of ectopic mandibular third molar to the lower border of mandible.

The surgical removal of impacted lower third molar is an ordinary intervention. The treatment of choice in this pathology is an intraoral or, seldom, extraoral surgical approach. Various surgical procedures have been described to remove ectopic mandibular teeth. The more common technique is an intraoral approach (so named "conservative"), even when the tooth is located in an ectopic area. However, the "intraoral approach" is often related with the difficulty of view, the bleeding of the surgical site, and with the possible lesions of inferior alveolar or lingual nerve. From the other side, a nonconservative surgical approach like "extraoral pathway" may be associated with no aesthetic cutaneous postoperative scar tissue. The aim of those 2 study cases is to highlight the management of infected ectopic third molars located close to the lower border of the mandibular body, underlining the anatomical land markers of the submandibular area. The authors have applied the extraoral pathway using an incision of small size. From our analysis, the treatment of those typical can be managed by using a "mini-skin-incision" (so termed as mini-submandibular approach) respecting the cosmetic expectations of the patients.

Surface biocompatibility of differently textured titanium implants with mesenchymal stem cells.

OBJECTIVE: The major challenge for contemporary dentistry is restoration of missing teeth; currently, dental implantation is the treatment of choice in this circumstance. In the present study, we assessed the interaction between implants and Dental Pulp Stem Cells (DPSCs) in vitro by means of 3D cell culture in order to better simulate physiological conditions. METHODS: Sorted CD34+ DPSCs were seeded onto dental implants having either a rough surface (TriVent) or one coated with a ceramic layer mimicking native bone (TiUnite). We evaluated preservation of DPSC viability during osteogenic differentiation by an MTT assay and compared mineralized matrix deposition with SEM analysis and histological staining; temporal expression of osteogenic markers was evaluated by RT-PCR and ELISA. RESULTS: Both surfaces are equally biocompatible, preserve DPSC viability, stimulate osteogenic differentiation, and increase the production of VEGF. A slight difference was observed between the two surfaces concerning the speed of DPSC differentiation. SIGNIFICANCE: Our study of the two implant surfaces suggests that TriVent, with its roughness, is capable of promoting cell differentiation a bit earlier than the TiUnite surface, although the latter promotes greater cell proliferation.

An unusual case of oral hirsutism in a patient with polycystic ovarian syndrome.

Hirsutism is the presence of terminal hair in women in a male-like pattern, which represents the clinical expression of an underlying excess of androgen (hyperandrogenism). Numerous conditions and serious diseases can result in high levels of circulating androgens, although the most common cause of hirsutism is polycystic ovary syndrome (PCOS). The following classic clinical features characterize PCOS: irregular menstrual periods, infertility, excess hair growth, and obesity. The diagnosis of this disease is related to the discovery of clinical signs that are confirmed by hematochemical examinations. We present a clinical case that is relatively unusual owing to the appearance of black hairs that are similar to nasal hair in the oral mucosa, which is an atypical location. This unusual case was considered to be oral hirsutism, and its presence constituted the essential element in the diagnosis of PCOS. The hypothesis proposed for this unusual condition could be correlated to the high rate of circulating testosterone that may have influenced and led to the development and appearance of the hair follicles in the oral mucosa.

Human mandible bone defect repair by the grafting of dental pulp stem/progenitor cells and collagen sponge biocomplexes.

In this study we used a biocomplex constructed from dental pulp stem/progenitor cells (DPCs) and a collagen sponge scaffold for oro-maxillo-facial (OMF) bone tissue repair in patients requiring extraction of their third molars. The experiments were carried out according to our Internal Ethical Committee Guidelines and written informed consent was obtained from the patients. The patients presented with bilateral bone reabsorption of the alveolar ridge distal to the second molar secondary to impaction of the third molar on the cortical alveolar lamina, producing a defect without walls, of at least 1.5 cm in height. This clinical condition does not permit spontaneous bone repair after extraction of the third molar, and eventually leads to loss also of the adjacent second molar. Maxillary third molars were extracted first for DPC isolation and expansion. The cells were then seeded onto a collagen sponge scaffold and the obtained biocomplex was used to fill in the injury site left by extraction of the mandibular third molars. Three months after autologous DPC grafting, alveolar bone of patients had optimal vertical repair and complete restoration of periodontal tissue back to the second molars, as assessed by clinical probing and X-rays. Histological observations clearly demonstrated the complete regeneration of bone at the injury site. Optimal bone regeneration was evident one year after grafting. This clinical study demonstrates that a DPC/collagen sponge biocomplex can completely restore human mandible bone defects and indicates that this cell population could be used for the repair and/or regeneration of tissues and organs.

Human dental pulp stem cells: from biology to clinical applications.

Dental pulp stem cells (DPSCs) can be found within the "cell rich zone" of dental pulp. Their embryonic origin, from neural crests, explains their multipotency. Up to now, two groups have studied these cells extensively, albeit with different results. One group claims that these cells produce a "dentin-like tissue", whereas the other research group has demonstrated that these cells are capable of producing bone, both in vitro and in vivo. In addition, it has been reported that these cells can be easily cryopreserved and stored for long periods of time and still retain their multipotency and bone-producing capacity. Moreover, recent attention has been focused on tissue engineering and on the properties of these cells: several scaffolds have been used to promote 3-D tissue formation and studies have demonstrated that DPSCs show good adherence and bone tissue formation on microconcavity surface textures. In addition, adult bone tissue with good vascularization has been obtained in grafts. These results enforce the notion that DPSCs can be used successfully for tissue engineering.

The effect of Delaire cheilorhinoplasty on midfacial growth in patients with unilateral cleft lip and palate.

The aim of this research was to evaluate the effect of the Delaire surgical technique on the midfacial morphology in a group of subjects with a congenital unilateral cleft of lip and palate (UCLP), prior to orthodontic treatment. Thirty-five UCLP (15 left and 20 right) patients (16 males and 19 females, mean age 7.03+/-0.9 years; age range 8.7-5.0 years), treated for the correction of congenital malformation, were retrospectively selected. Analysis of midfacial growth was undertaken on lateral cephalograms, and the data were compared with reference values (Ricketts analysis). A Mann-Whitney ranked sum test was used to detect significant differences between the findings and reference values. P

Comparison between genetic portraits of osteoblasts derived from primary cultures and osteoblasts obtained from human pulpar stem cells.

Harvesting bone for autologous grafting is a daily problem encountered by craniofacial and oral surgeons. Stem cells derived from human dental pulp are able to differentiate in osteoblasts and are a potential source of autologous bone produced in vitro. However, as stem cells are characterized by self-renewing and commitment in several cellular subtypes (ie, pluripotential differentiation), some concerns may arise as regards their potential uncontrolled proliferation. To screen the behavior of osteoblasts derived from human pulpar stem cells (ODHPSCs), we used microarray techniques to identify genes that are differently regulated in ODHPSC in comparison to normal osteoblasts (NOs). Osteoblasts derived from human pulpar stem cells were obtained from human dental pulp, and cells were selected using a cytometer. The cell profile was c-kit+/CD34+/STRO-1+/CD45-. These cells were capable of differentiation of osteoblasts in vitro. By using DNA microarrays containing 19,200 genes, we identified in ODHPSC some genes whose expression was significantly up- and downregulated compared to NO. The differentially expressed genes have different functional activities: (a) cell differentiation, (b) developmental maturation, (c) cell adhesion, and (d) production of cytoskeleton elements. Thus, some molecular differences exist between NO and ODHPSC, although the previously considered histologic parameters show a normal phenotype.

Dental pulp stem cells: a promising tool for bone regeneration.

Human tissues are different in term of regenerative properties. Stem cells are a promising tool for tissue regeneration, thanks to their particular characteristics of proliferation, differentiation and plasticity. Several "loci" or "niches" within the adult human body are colonized by a significant number of stem cells. However, access to these potential collection sites often is a limiting point. The interaction with biomaterials is a further point that needs to be considered for the therapeutic use of stem cells. Dental pulp stem cells (DPSCs) have been demonstrated to answer all of these issues: access to the collection site of these cells is easy and produces very low morbidity; extraction of stem cells from pulp tissue is highly efficiency; they have an extensive differentiation ability; and the demonstrated interactivity with biomaterials makes them ideal for tissue reconstruction. SBP-DPSCs are a multipotent stem cell subpopulation of DPSCs which are able to differentiate into osteoblasts, synthesizing 3D woven bone tissue chips in vitro and that are capable to synergically differentiate into osteoblasts and endotheliocytes. Several studied have been performed on DPSCs and they mainly found that these cells are multipotent stromal cells that can be safety cryopreserved, used with several scaffolds, that can extensively proliferate, have a long lifespan and build in vivo an adult bone with Havers channels and an appropriate vascularization. A definitive proof of their ability to produce dentin has not been yet done. Interestingly, they seem to possess immunoprivileges as they can be grafted into allogenic tissues and seem to exert anti-inflammatory abilities, like many other mesenchymal stem cells. The easy management of dental pulp stem cells make them feasible for use in clinical trials on human patients.

Scaffold's surface geometry significantly affects human stem cell bone tissue engineering.

In this study, we have observed dental pulp stem cells (SBP-DPSCs) performances on different scaffolds, such as PLGA 85:15, hydroxyapatite chips (HA) and titanium. Stem cells were challenged with each engineered surface, either in plane cultures or in a rotating apparatus, for a month. Gingival fibroblasts were used as controls. Results showed that stem cells exerted a different response, depending on the different type of textured surface: in fact, microconcavities significantly affected SBP-DPSC differentiation into osteoblasts, both temporally and quantitatively, with respect to the other textured surfaces. Actually, stem cells challenged with concave surfaces differentiated quicker and showed nuclear polarity, an index of secretion, cellular activity and matrix formation. Moreover, bone-specific proteins were significantly expressed and the obtained bone tissue was of significant thickness. Thus, cells cultured on the concave textured surface had better cell-scaffold interactions and were induced to secrete factors that, due to their autocrine effects, quickly lead to osteodifferentiation, bone tissue formation, and vascularization. The worst cell performance was obtained using convex surfaces, due to the scarce cell proliferation on to the scaffold and the poor matrix secretion. In conclusion, this study stresses that for a suitable and successful bone tissue reconstruction the surface texture is of paramount importance.

Concave pit-containing scaffold surfaces improve stem cell-derived osteoblast performance and lead to significant bone tissue formation.

BACKGROUND: Scaffold surface features are thought to be important regulators of stem cell performance and endurance in tissue engineering applications, but details about these fundamental aspects of stem cell biology remain largely unclear. METHODOLOGY AND FINDINGS: In the present study, smooth clinical-grade lactide-coglyolic acid 85:15 (PLGA) scaffolds were carved as membranes and treated with NMP (N-metil-pyrrolidone) to create controlled subtractive pits or microcavities. Scanning electron and confocal microscopy revealed that the NMP-treated membranes contained: (i) large microcavities of 80-120 microm in diameter and 40-100 microm in depth, which we termed primary; and (ii) smaller microcavities of 10-20 microm in diameter and 3-10 microm in depth located within the primary cavities, which we termed secondary. We asked whether a microcavity-rich scaffold had distinct bone-forming capabilities compared to a smooth one. To do so, mesenchymal stem cells derived from human dental pulp were seeded onto the two types of scaffold and monitored over time for cytoarchitectural characteristics, differentiation status and production of important factors, including bone morphogenetic protein-2 (BMP-2) and vascular endothelial growth factor (VEGF). We found that the microcavity-rich scaffold enhanced cell adhesion: the cells created intimate contact with secondary microcavities and were polarized. These cytological responses were not seen with the smooth-surface scaffold. Moreover, cells on the microcavity-rich scaffold released larger amounts of BMP-2 and VEGF into the culture medium and expressed higher alkaline phosphatase activity. When this type of scaffold was transplanted into rats, superior bone formation was elicited compared to cells seeded on the smooth scaffold. CONCLUSION: In conclusion, surface microcavities appear to support a more vigorous osteogenic response of stem cells and should be used in the design of therapeutic substrates to improve bone repair and bioengineering applications in the future.

In vitro bone production using stem cells derived from human dental pulp.

To harvest bone for autologous grafting is a daily problem encountered by craniofacial and oral surgeons. Stem cells derived from human dental pulp are able to differentiate in osteoblasts and are a potential source of autologous bone produced in vitro. The authors describe their preliminary results in this new field with its potential application in craniomaxillofacial surgery. Dental pulp was gently extracted from 34 human permanent teeth (all third molars) of patients 19 to 37 years of age. After they were digested, the cells were selected using a cytometer for c-kit, STRO-1, CD34, CD45, and then for CD44 and RUNX-2. This study, made on a considerable number of cases, provided evidence that dental pulp is extremely rich in stem cells, which were c-kit+/CD34+/STRO-1+/CD45-, capable of differentiation toward several stromal-derived differentiated cells and mainly osteoblasts. These findings, supported by the large number of cases, are of great interest for tissue regeneration, tissue-based clinical therapies, and transplantation.

First International Meeting on "Stem Cell Applications in the Craniofacial Region".

During the 1st International Meeting on "Stem Cell Applications in the Craniofacial Region" promoted in Naples (Italy), invited researchers presented theirwork and the most innovative methods regarding stem cells (SCs) and their application to the craniofacial region of the human body. In addition, some researchers showed their case-reports on craniofacial reconstruction using either osteo-distraction or reconstruction surgical methods. The aim of this biannual meeting is to stimulate discussion, improve knowledge and promote scientific collaboration among basic and clinical scientists in the main topics of SC use in therapy. A summary of this meeting is given.