Interleukin- 1 gene polymorphisms as assessed in a 10-year study of patients with early-onset periodontitis.

Our 10-year study of early-onset periodontitis (EOP) patients includes repeated clinical observations, microbiological characteristics and analysis of genetic polymorphism of IL-1A and IL-1B genes. Twenty patients (age 15-26 years) were divided according to the clinical status in the 4th year into a group with mean number of teeth with bleeding on probing (BP) 9.8 and mean number of teeth with periodontal pocket (PP) 2.23, and a group with mean number of teeth with BP 5.37 and no PP. Significantly higher values of mean BP and PP were found among the groups during the study but a strong progression of disease was found only in 3 patients. The risk IL-1A allele-2 and IL-1B allele-2 genotype and bacterial presence were analyzed by DNA hybridization methods. No significant differences of bacteria composition (Treponema denticola, Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans) were found between the groups. A higher prevalence of composite IL-1 genotype was detected in the group of EOP patients with progressive disease. Early finding of the disease followed by conservative therapy could positively influence the disease progression. EOP treated in early stages may, but need not, develop into the aggressive form in the presence of risk genotype IL-1.

Th1 and Th2 cytokine profile in patients with early onset periodontitis and their healthy siblings.

Early onset periodontitis (EOP) is a chronic inflammatory periodontal disease with a strong genetic link affecting individuals aged 17 to 25. In the familial studies we tested the hypothesis about the role of Th1 and Th2 cytokines in the pathogenesis of EOP disease. The study involved 6 individuals with EOP disease and their 6 siblings with healthy periodontium. Actinobacillus actinomycetemcomitans (A. a), a bacterium typical for EOP, was detected in all people studied. Th1 and Th2 cytokine production was measured after in vitro stimulation. Peripheral blood mononuclear cells (PBMC) were isolated and cultivated for 24 h and 7 days with PWM, A. a. or Escherichia coli. The levels of IL-4, IFN-gamma, IgA, IgG and IgM were measured by ELISA methods. After in vitro stimulation of PBMC, a significantly higher production of IL-4 and significantly lower production of IFN-gamma were found in the group of patients compared with their healthy siblings. The increased level of IL-4 in patients was in good agreement with an increased level of IgM after stimulation of lymphocytes with E. coli. These results support Seymour's hypothesis according to which patients with progressive disease primarily activate Th2 lymphocytes while non-susceptible individuals activate Th1 lymphocytes.

Noncontact Er:YAG laser ablation: clinical evaluation.

OBJECTIVE: The aim of this study is to evaluate the quality of laser ablation in comparison with the classical drilling preparation. METHODS: For the experiment, the Er:YAG laser drilling machine was used. The system had a laser head, water cooler, and power supply with automatic control. Spot size of 300-350 microns was used for the preparation. Repetition rate of 1-4 Hz, and pulse energies of 100-400 mJ with water spray were chosen. Cavity shape in comparison with classical drill, time of preparation, and influence of cavity shape on filling materials retention in accordance with the U.S. Public Health Service System were used. The evaluation criteria for noncontact Er:YAG ablation were done. RESULTS: The cavity shape is irregular, but spot surface has larger area and microretentive appearance. Caries of enamel and dentin were treated with a noncontact preparation. It was possible to remove the old insufficient fillings, except for amalgam or metal alloys. The average number of pulses was 111.22 (SE 67.57). Vibrations of microexplosions during preparation were felt by patients on 14 cavities; however, nobody felt unpleasant pain. The qualities of filling materials in laser cavities were very stable; however, cavo surface margin discoloration of 82-86% of Alfa rating could be a problem. Changes of the color and anatomic form of the tooth were observed in 4-8%. CONCLUSIONS: In comparison with the classical treatment, it could be said that the retention and quality of filling materials is the same or very similar.

Dentin and pulp response to Erbium:YAG laser ablation: a preliminary evaluation of human teeth.

OBJECTIVE: We determined the real effect of Erbium:YAG laser ablation on human teeth in vivo. SUMMARY BACKGROUND DATA: We advocated the idea that overheating of teeth, specially pulp damage can be avoided if correct laser parameters are used. METHODS: We evaluated human premolars scheduled for extraction during orthodontic treatment. Before tooth extraction, an oval cavity preparation was made with a pulsed Er:YAG laser. After extraction, the teeth were decalcified for 6 weeks. Routine staining with haematoxylin and eosin was performed on longitudinal section. One hundred seventy-two sections were prepared and examined in a light microscope. RESULTS: Under Er:YAG laser application, reduction of the dentin layer was observed. Dentinal tubules had a radial course up to the surface. No cracks or structural injury were observed. Inflammatory reaction in the pulp was not found. The vascularity of the pulp was normal. The odontoblasts were of the usual spindle-like or star-like cell shape. The cementum and epithelial attachment were healthy. No changes of structure or indications of inflammation were observed. CONCLUSIONS: The results of this in vivo experiment on human teeth confirm safety of Er:YAG laser ablation of enamel and dentin under the conditions described.

Expression of the LFA-1 beta molecule on peripheral blood leukocytes of patients with early-onset periodontitis: effects of dental plaque microbes.

The effect of dental plaque bacteria on LFA-1 beta expression on peripheral blood leukocytes was studied in 20 patients with early-onset periodontitis and in 10 healthy controls. Stimulation of PMN with selected dental plaque bacteria which play a role in the pathogeny of periodontitis significantly increased the expression of LFA-1 beta in the group of patients as compared with the controls.

Evaluation of the surface changes in enamel and dentin due to possibility of thermal overheating induced by Erbium:YAG laser radiation.

This study investigates the thermal danger of Erbium (Er):YAG laser ablation. Classical preparation techniques have many disadvantages caused by unfavorable changes of temperature, pressure, and by mechanical vibrations. The effect of mechanical vibrations and pressure is eliminated by use of laser ablation technique. The purpose of this study was to analyze the side effects resulting from thermal changes of enamel and dentin in extracted human teeth subjected to pulsed Er:YAG laser radiation using both wet and dry ablation methods. The micrographs of the sections were checked and measured afterwards. The effect of the investigated laser irradiation on the origin of cracks was analyzed in the scanning electron microscope. The hard structures of the teeth were observed under transmitted and polarized light. The occurrence of cracks can be directly correlated to overheating during dry enamel ablation, because heat is generated by absorption of the laser beam by enamel and dentin. The addition of water mist during irradiation not only enables rapid ablation of enamel and dentin, but offers thermal protection to the pulp. The heat changes to the pulp caused by an energy level of 200 mJ from the tested laser system may be reduced by adding a fine water spray during the lasing procedure.

[Partial results of an investigation of the state of dentition of the Czechoslovak population with regard to targets of WHO for the year 2000]. / Dílci výsledky výberového setreni stavu chrupu obyvatel CSSR z hlediska cílu SZO do R. 2000.

In 1987 a nation-wide survey of the state of dentition of Czechoslovak population in age groups of 2-65 years and above was made. The paper presents the results in the age category of 5-6 years, 12 years, 18 years, 35-44 and 65 year and more, with regard to criteria defined for WHO targets for the year 2000. Data for the CSSR, SSR and CSSR are presented separately.

[Comparison of Czechoslovak and foreign toothpastes]. / Srovnáni Ceskoslovaenských a zahranicních zubních past.

The authors made a nation-wide investigation focused on the consumption of foreign toothpastes and their evaluation, as compared with locally produced ones. They also assessed the properties of selected foreign toothpastes according to the Czechoslovak norm by laboratory tests. The investigation related that foreign toothpastes are purchased by one quarter of the subjects where enquiries were made. The main reason for selection of a foreign toothpaste was better taste and a better sensation of fragrance. People appreciate also the attractivity packing and adequate information on the properties and composition of the toothpaste. As compared with local toothpastes, the better taste of foreign ones is emphasized. Laboratory tests of the properties of foreign tooth pastes, as compared with local revealed that from the physico-chemical and microbiological aspect local toothpastes compare favourably with foreign ones. However, the organoleptic properties, packing and information are not comparable.

[Czechoslovak toothpaste--present choice, consumption, quality]. / Ceskoslovenské zubní pasty--soucasný stav výberu, spotreby a jakosti.

The authors made a nation-wide survey focused on the choice, appreciation of different properties of toothpastes and the popularity of different brands. They also evaluated the quality of some toothpastes according to Czechoslovak standards. The results revealed that the attitude of the public as regards toothpastes is correct. The great majority of subjects consider fluorine and therapeutic substances an important part of toothpastes. The majority of subjects are satisfied with the supply, one third of the people complain that some types are in short supply. More than half the subjects ask for toothpastes with texts providing information. The majority of toothpastes met the demand defined by the Czechoslovak standards. Some shortcomings were revealed during organoleptic evaluation and in the technology of production. The authors discuss the small consumption of toothpastes which must be increased by the health educational activities of dental surgeons but also by increased attention of manufactures and the network of shops to the technology, distribution and propagation of toothpastes.