Hanna Gerber

Total antioxidant status and 8-hydroxy-2'-deoxyguanosine levels in gingival and peripheral blood of periodontitis patients.

Introduction:The aim of this study was to determine 8-OHdG concentration as a biomarker of oxidant-induced DNA damage and to assess total antioxidant status (TAS) in gingival and peripheral blood during periodontal lesion.Materials and Methods:The study included 56 untreated periodontitis patients (26 with aggressive periodontitis, and 30 with chronic periodontitis (CP). The control group consisted of 25 healthy volunteers without pathological changes in the periodontium. Competitive ELISA was used to measure 8-OHdG. A colorimetric method based on the reduction of ABTSo+ radical cation generation was used to measure TAS.Results:Significantly higher 8-OHdG concentrations were detected in the gingival blood in both groups of patients with periodontitis than in the control group. Subjects with CP had significantly decreased TAS levels in the gingival blood compared with the control group. A significantly decreased TAS level in the peripheral blood in both patient groups compared with the control group was found. Significant positive correlation between TAS levels in venous and gingival blood in all the periodontitis patients and in the CP group was observed.Conclusions:The oxidative burst in periodontitis may lead to significant local damage to nucleic acids. The significantly decreased TAS level in the gingival blood of CP patients compared with the healthy subjects suggests the possibility of a significant decrease in local antioxidant system capacity during the course of periodontitis. The decreased TAS level in the peripheral blood in the group of all patients with periodontitis may be one of the pathogenic mechanisms underlying the links between periodontal disease and several systemic diseases for which periodontitis is regarded as a independent risk factor.

Photodynamic therapy in head and neck cancer.

Photodynamic therapy (PDT) is a special type of treatment involving the use of a photosensitizer or a photosensitizing agent along with a special type of light, which, combined together, induces production of a form of oxygen that is used to kill surrounding cells in different areas of the human body. Specification of the head and neck region requires different approaches due to the surrounding of vital structures. PDT can also be used to treat cells invaded with infections such as fungi, bacteria and viruses. The light beam placed in tumor sites activates locally applied drugs and kills the cancer cells. Many studies are taking place in order to invent better photosensitizers, working on a larger scale and to treat deeply placed and larger tumors. It seems that PDT could be used as an alternative surgical treatment in some tumor types; however, all clinicians should be aware that the surgical approach is still the treatment of choice. PDT is a very accurate and effective therapy, especially in early stages of head and neck squamous cell carcinomas (HNSCC), and can greatly affect surgical outcomes in cancerous patients. We present a detailed review about photosensitizers, their use, and therapeutic advantages and disadvantages.

Human papillomavirus and its influence on head and neck cancer predisposition.

Human papillomavirus (HPV) is a virus often infecting humans. It is often present on skin or mucous membranes. These diverse DNA viruses are often linked to many various benign and malignant neoplastic lesions. Over 40 types of HPV are transmitted through sexual contact and infect the anogenital region which might be secondly transmitted to the oral mucous. Over 150 HPV viruses are defined according to the invaded site. Oral papillomas are marked with numbers 6, 7, 11, 16 and 32. Squamous cell papilloma is often found in laryngeal epithelial tumor associated with HPV-6 and HPV-11 and also HPV-16 in oral squamous cell carcinoma (OSCC). In the last 15 years OSCC has become more common in children and young adults. The role of HPV virus causing oral squamous cell carcinomas is more often realized, but peoples lack of knowledge and risky sexual behavior is still the main factor in growing HPV infections.

New nano-hydroxyapatite in bone defect regeneration: A histological study in rats

Many types of bone substitute materials are available on the market. Researchers are refining new bone substitutes to make them comparable to autologous grafting materials in treatment of bone defects. The purpose of the study was to evaluate the osseoconductive potential and bone defect regeneration in rat calvaria bone defects treated with new synthetic nano-hydroxyapatite. The study was performed on 30 rats divided into 5 equal groups. New preproduction of experimental nano-hydroxyapatite material by NanoSynHap (Poznań, Poland) was tested and compared with commercially available materials. Five mm critical size defects were created and filled with the following bone grafting materials: 1) Geistlich Bio-Oss®; 2) nano-hydroxyapatite+β-TCP; 3) nano-hydroxyapatite; 4) nano-hydroxyapatite+collagen membrane. The last group served as controls without any augmentation. Bone samples from calvaria were harvested for histological and micro-ct evaluation after 8 weeks. New bone formation was observed in all groups. Histomorphometric analysis revealed an amount of regenerated bone between 34.2 and 44.4% in treated bone defects, whereas only 13.0% regenerated bone was found in controls. Interestingly, in group 3, no significant particles of the nano-HA material were found. In contrast, residual bone substitute material could be detected in all other test groups. Micro-CT study confirmed the results of the histological examinations. The new nano-hydroxyapatite provides comparable results to other grafts in the field of bone regeneration.

Cell reactions and immune responses to photodynamic therapy in oncology.

Photodynamic therapy (PDT) is a noninvasive, highly selective method for the treatment of diseases characterized by uncontrolled cell proliferation. It was clinically approved more than 30 years ago. PDT involves the selective uptake of a photosensitizer (PS) by neoplastic tissue, which is able to produce reactive oxygen species (ROS) upon irradiation with visible or near-infrared (NIR) light. ROS induce destruction of target cells and damage of tumor-associated vasculature and activate an antitumor immune response, leading to tumor regression. The execution of this process is attained by different mechanisms, including host immune responses and activation of cell death pathways: apoptosis and necrosis.

Use of primary culture of human fibroblasts in gingiva augmentation procedure

Abstract Background: The aim of this study was to assess gingival aesthetic after usage of an own method of primary culture of human fibroblasts derived from the connective tissue of oral cavity keratinized gingiva on collagenous carrier in gingival augmentation procedures. Materials and methods: Procedures were performed on 10 patients (7 females, 3 males) aged 18–35 years. In total, 34 teeth in the anterior part of the maxilla and the mandible underwent treatment. The protocol consisted of (1) preparing the patient for tissue biopsy, (2) biopsy of keratinized tissue, (3) laboratory tissue culture, (4) application of expanded cells into the recipient site, and (5) post-procedure management. Aesthetic index, pocket depth (PD), and plaque (PI1) and after surgery complications were examined. Results: There was post-procedure aesthetic improvement in all 34 cases compared with the pre-procedure condition (grade 1), and furthermore a significant decrease in PD and PI1 were revealed. Conclusion: Use of own method of primary culture of human fibroblasts on a collagenous carrier for gingival augmentation is an aesthetic method of mucogingival complex repair.

Immediate loading of an implant with fine threaded neck – bone resorption and clinical outcome of single tooth restorations in the maxilla

Abstract One of the conditions for ensuring success in implant surgery with an immediate loading (IL) protocol is to achieve maximum primary stability (PS) through the use of dental implants with the appropriate design and surface and a properly prepared osseous bed. The aim of this study was to assess the stability, degree of osseointegration, and success rate after inserting an implant with IL in an osseous bed prepared with burs or an ultrasonic device. Twenty-five patients requiring single tooth replacement (tioLogic; Dentaurum, Ispringen, Germany) in the aesthetic zone were divided randomly into the test (K0) and control (K1) groups. The following factors were investigated: primary (PS-ISQ) and secondary (SS-ISQ) stability- implant stability quotient (ISQ value) by Ostell Mentor, initial width of the alveolar ridge, marginal bone loss (MBL), and buccal bone thickness. The effectiveness of the implant treatment 1 year after the surgery was 100% for group K0 and 93.3% for group K1. A significant correlation was observed between PS and MBL after 1 month. No statistically significant differences were noted between the groups with regard to MBL after 6 months (K0 0.5±0.4 mm vs. K1 0.8±1.3 mm), PS-ISQ (K0 70±4 vs. K1 71±4), and SS-ISQ (K0 70±2 vs. K1 72±3). The average ISQ value of 70±4 is sufficient to allow for IL. A high level of PS results in lower MBL.

Genetic Factors Involved in Mandibular Prognathism

Mandibular prognathism is defined as an abnormal forward projection of the mandible beyond the standard relation to the cranial base and it is usually categorized as both a skeletal Class III pattern and Angle Class III malocclusion. The etiology of mandibular prognathism is still uncertain, with various genetic, epigenetic, and environmental factors possibly involved. However, many reports on its coexistence in both twins and segregation in families suggest the importance of genetic influences. A multifactorial and polygenic background with a threshold for expression or an autosomal dominant mode with incomplete penetrance and variable expressivity are the most probable inheritance patterns. Linkage analyses have, thus far, shown the statistical significance of such loci as 1p22.1, 1p22.3, 1p32.2, 1p36, 3q26.2, 4p16.1, 6q25, 11q22, 12pter-p12.3, 12q13.13, 12q23, 12q24.11, 14q24.3 to 31.2, and 19p13.2. The following appear among candidate genes: MATN1, EPB41, growth hormone receptor, COL2A1, COL1A1, MYO1H, DUSP6, ARHGAP21, ADAMTS1, FGF23, FGFR2, TBX5, ALPL, HSPG2, EVC, EVC2, the HoxC gene cluster, insulin-like growth factor 1, PLXNA2, SSX2IP, TGFB3, LTBP2, MMP13/CLG3, KRT7, and FBN3. On the other hand, MYH1, MYH2, MYH3, MYH7, MYH8, FOXO3, NFATC1, PTGS2, KAT6B, HDAC4, and RUNX2 expression is suspected to be involved in the epigenetic regulations behind the mandibular prognathism phenotype.

Bone markers in craniofacial bone deformations and dysplasias.

Various forms of bony deformations and dysplasias are often present in the facial skeleton. Bone defects can be either localized or general. Quite often they are not only present in the skull but also can be found in other parts of the skeleton. In many cases the presence and levels of specific bone markers should be measured in order to fully describe their activity and presence in the skeleton. Fibrous dysplasia (FD) is the most common one in the facial skeleton; however, other bone deformations regarding bone growth and activity can also be present. Every clinician should be aware of all common, rare and uncommon bony diseases and conditions such as cherubism, Pagets disease, osteogenesis imperfecta and others related to genetic conditions. We present standard (calcium, parathyroid hormone, calcitonin, alkaline phosphatase, vitamin D) and specialized bone markers (pyridinium, deoxypyridinium, hydroxyproline, RANKL/RANK/OPG pathway, growth hormone, insulin-like growth hormone-1) that can be used to evaluate, measure or describe the processes occurring in craniofacial bones.

Protein tyrosine phosphatase receptor R and Z1 expression as independent prognostic indicators in oral squamous cell carcinoma

The actions of tyrosine phosphorylation and dephosphorylation are controlled by tyrosine kinases and phosphatases. Although substantial previous data have revealed the role of several protein tyrosine phosphatases (PTPs) in various cancers, the function of protein tyrosine phosphatase receptor R (PTPRR) and protein tyrosine phosphatase, receptor‐type, Z polypeptide 1 (PTPRZ1) proteins in oral cavity squamous cell carcinoma (SCC) has not been studied to date.