Izabela Szarmach

Fractal Analysis of Dental Radiographic Images in the Irregular Regions of Interest

The irregularity or ”roughness” of medical images is quantified by means of fractal dimension D. For medical images diagnostically important information often lies in the texture. In this paper we describe the application of the intensity difference scaling method for assessment of the fractal dimension D in the irregular regions of interest (irregular ROI-s). Near boundary between different tissues or structures the values of fractal dimensions changed significantly. It is difficult to fit entire regular region of interest within the examined organ with simultaneous inclusion of the relevant fragment, and at the same time to avoid the influence of boundaries.

Orthodontic treatment modifies the oxidant–antioxidant balance in saliva of clinically healthy subjects

PURPOSE The aim of our study was to analyse salivary markers of oxidative stress and an antioxidant response in clinically healthy subjects with fixed orthodontic appliances. MATERIAL/METHODS 37 volunteers were included in the study. Unstimulated (UWS) and stimulated (SWS) whole saliva were analysed for oxidative and antioxidant status and nickel levels immediately before the insertion of the appliances, an one week after and twenty four weeks after the insertion of fixed appliances. RESULTS A significant increase in tiobarbituric acid reactive substance (TBARS) and total oxidant status (TOS) one week, and total protein concentration twenty four weeks after the attachment of orthodontic appliances was found in the saliva. The markers of antioxidant status: superoxide dismutase (SOD), catalase (CAT), uric acid (UA), peroxidase (Px), and total antioxidant status (TAS) were not changed in all periods in UWS. In SWS a significant decrease in SOD1 and CAT was found whereas Px was increased one week after treatment and UA twenty four weeks following treatment. TAS was decreased in UWS and SWS twenty four weeks after orthodontic treatment. Oxidative status index (OSI) was elevated both in UWS and SWS one week after orthodontic treatment in comparison to the results obtained before and twenty four weeks. One week after treatment an increased concentration of nickel was also observed. CONCLUSIONS Orthodontic treatment modifies the oxidative-antioxidative balance in the saliva of clinically healthy subjects. Increased nickel concentration in saliva, released from orthodontic appliances, seems to be responsible for changes in the oxidative status of the saliva.

Caspase-3 as an important factor in the early cytotoxic effect of nickel on oral mucosa cells in patients treated orthodontically

INTRODUCTION The effect of fixed orthodontic appliances on biochemical changes in saliva and pathophysiological status of the oral cavity is not clear. Recent data showed that nickel (Ni) released from orthodontic appliances can decrease cellular viability, induce DNA damage and apoptosis in oral mucosa cells. Since the mechanism of these Ni effects is unknown, the aim of our study was to analyze the expression of caspase-3 in epithelial cells of oral mucosa in healthy individuals treated orthodontically. MATERIAL AND METHODS Twenty-eight volunteers participated in the study. Epithelial cells were collected from oral mucosa directly before appliance insertion, one week after the insertion, and 24 four weeks after the insertion of fixed appliances. Cellular identification and measurements were conducted by light microscopy. Caspase-3 expression was evaluated immunochemically. Nickel concentration in saliva was also determined. RESULTS A significantly higher number of oral epithelial cells with caspase-3 immunoreactivity in was found one week, but not 24 weeks, after orthodontic treatment. The enhanced expression of caspase-3 was accompanied by increased nickel concentration in saliva. CONCLUSIONS Our data suggests that nickel released from orthodontic appliances can activate caspase-3 and this mechanism may be partially responsible for the cytotoxic action of nickel in the oral cavity of orthodontically-treated individuals.

Eight-Week Consumption of High-Sucrose Diet Has a Pro-Oxidant Effect and Alters the Function of the Salivary Glands of Rats

A high-sucrose diet (HSD) is widely known for its cariogenic effects and promotion of obesity, insulin resistance, type 2 diabetes, and cancer. However, the impact of the HSD diet on the salivary gland function as well as the level of salivary oxidative stress is still unknown and requires evaluation. Our study is the first to determine both redox balance and oxidative injury in the parotid and submandibular glands of rats fed the HSD diet compared to the control group. We have demonstrated that uric acid concentration and the activity of superoxide dismutase and peroxidase varied significantly in both the submandibular and parotid glands of HSD rats vs. the control group. However, enhanced oxidative damage to proteins, lipids, and DNA (increase in advanced glycation end products, advanced oxidation protein products, 4-hydroxynonenal, and 8-hydroxy-2’-deoxyguanosine) was observed only in the parotid glands of HSD rats. Moreover, the HSD diet also reduced the total protein content and amylase activity in both types of salivary glands and decreased the stimulated salivary flow rate. To sum up, an HSD diet reduces salivary gland function and disturbs the redox balance of the parotid as well as submandibular salivary glands. However, the parotid glands are more vulnerable to both antioxidant disturbances and oxidative damage.

The influence of occlusal discrepancies on the disclosure of pathological tooth wear early stages - personal experience

Streszczenie Ścieranie się zębów jest podstawowym, zależnym od wieku mechanizmem dostosowawczym w układzie stomatognatycznym. Jeśli jednak progresja starcia jest duża prowadząc do znacznej utraty tkanek twardych zębów w krótkim czasie, to proces ten może być uważany za patologiczny. Głównym celem pracy było przedstawienie konsekwencji patologicznego starcia zębów w zależności od zaburzeń w okluzji. Przedstawiono strategię profilaktyki w odniesieniu do patologicznego starcia zębów oraz zasady postępowania w sytuacji, gdy proces patologicznego starcia zębów nie jest zaawansowany i nie doszło do utraty wysokości zwarcia centralnego. Ocena okluzji przed, w trakcie i po zakończeniu postępowania diagnostyczno-rehabilitacyjnego oraz kontrola warunków okluzyjnych podczas każdej wizyty kontrolnej wydaje się być kluczowa w leczeniu patologicznego starcia zębów. Wpływ zaburzeń okluzyjnych na ujawnianie się wczesnych stadiów patologicznego starcia zębów – doświadczenia własne

Reduced systemic bone mineral density associated with a rare case of tooth and nail syndrome

PURPOSE This is the first report of a rare genetic tooth and nail syndrome (TNS) diagnosed in a 14-year-old Caucasian girl with a complete absence of the permanent dentition and, additionally, reduced total and lumbar spine bone mineral density (BMD). This coincidence suggests a new clinical manifestation of the disorder in which genetic factors and/or shared mechanisms may be responsible for the deterioration of the stomatognathic system, anodontia, nail phenotype and osteopenia. Low bone mass appears to be a new component of the syndrome. There is a rationale for bone densitometry scans assuming that patients with TNS may have an increased risk of osteopenia. Reduced BMD and, possibly, impaired bone quality and strength may produce difficulties or even exclude such patients from future treatment with dental implants.