Morphological Study Of Border Area Of Pulp-Capping Materials And Er:YAG Laser Prepared Hard Dental Surface.

INTRODUCTION: Vital pulp therapy involves biologically based therapeutic activities aimed at restoring health and preserving the vitality of cariously or traumatically damaged pulp. Adaptation of pulp-capping materials to the prepared tooth surface may be the key to the success of biological tooth treatment. AIM: To investigate the area of adaptation of synthetic tricalcium silicate cement, calcium hydroxide cement and mineral trioxide-aggregate to the dentin surface, prepared with the help of Er:YAG dental laser. MATERIAL AND METHODS: Four extracted human tooth cavities were prepared with the help of Er:YAG dental laser (LiteTouch, Syneron, Israel), establishing microcommunication with the pulp chamber less than 1 mm in diameter. As pulp-capping materials in the cavities we used tricalcium silicate cement (Biodentine, Septodont, France), calcium hydroxide cement (Dycal) and mineral-trioxide aggregate (ProRoot MTA), stirred and administered according to manufacturers' instructions. The first material fills the whole cavity and the other two are spread in a thin layer and sealed with glass ionomer cement. Thus prepared, the samples were left for three days at 37°C in humidified environment. The samples were prepared for scanning electron microscopy (SEM) by standard methodology. The border area surfaces of the materials and the dentin were scanned using electron microscopy. RESULTS: The morphological changes occurring to the Er:YAG laser prepared dentin and the structural characteristics of the studied pulp-capping materials are demonstrated using scanograms. The border areas where good contact of materials and dentinal tubules is established are thoroughly studied. Good adaptation is seen in three-calcium silicate cement, followed by mineral trioxide aggregate and calcium hydroxide cement. CONCLUSION: The dentin surface, prepared with Er:YAG laser demonstrates a very good adaptation of the three tested pulp-capping materials.

Situational analysis of the type and degree of resorption of the interdental septum of teeth with approximal amalgam restorations.

AIM: The aim of the study was to determine radiographically the type and degree of resorption of the interdental septum of teeth with approximal amalgam restorations in various iatrogenic clinical situations. METHODS: Situational analysis of the type and degree of resorption of the interdental septum was performed in 757 approximal amalgam restorations of Class II cavities (according to Black). Intraoral periapical retroalveolar radiographs were used for that purpose. The condition of the septum was investigated in restorations with correct shape, in restorations with a poorly restored anatomical form, unsatisfactory marginal adaptation, as well in restorations with no proximal contact with the adjacent tooth. RESULTS: The horizontal type of interdental septum resorption was the predominant type in all study groups. Restorations with poor anatomical form showed considerably higher incidence of vertical type of resorption in comparison with correctly shaped fillings. Similarly, restorations with unsatisfactory marginal adaptation demonstrated higher incidence of the disproportionate type of resorption than in the accurately formed group. A greater degree of resorption of the interdental septum was observed in restorations with incorrect anatomical form, with unsatisfactory marginal adaptation and with no contact with the adjacent tooth. CONCLUSION: The observed changes can be explained by the presence of significant, long-standing retention of bacterial plaque, as well as by the additional trauma caused while eating and maintaining personal oral hygiene.

Early clinical results from the use of 5% potassium nitrate in polycarboxylate cement for biological treatment of reversible pulpitis.

UNLABELLED: The aim of the present study was to obtain immediate and early clinical results from the use of 5% potassium nitrate (KNO3) in polycarboxylate cement for biological treatment of reversible pulpitis. MATERIAL AND METHODS: The method was applied in 140 teeth, mostly premolars and molars, with a clinical diagnosis of reversible pulpitis and indications for biological treatment of the inflamed dental pulp by means of indirect pulp capping. All teeth had clinically healthy periodontium and no non-carious lesions of the hard dental tissues. The study sample consisted of 127 patients aged between 16 and 40 years. The control group included 92 teeth in 78 patients, which were treated by a calcium hydroxide liner. The follow-up examinations were conducted 24 hours after treatment and on day 3 for the immediate results, and on days 7, 14, 30, and 90 for the early clinical results assessing the functional condition of the teeth, presence of thermal stimulus-induced pain and the measurements from the electric pulp vitality tests. The results were analysed with the analysis of variance and graphic analysis. RESULTS: The immediate and early clinical results of the biological treatment of reversible pulpitis with 5% KNO3 in polycarboxylate cement show that pain as a symptom of the initial inflammatory process in the dental pulp is rapidly and effectively relieved, leaving the treated teeth in good functional condition. The comparison of the measurements from the electric pulp tests of all teeth reveals a statistically significant difference (u = 8.51; P < 0.001) in favour of the group treated with potassium nitrate and polycarboxylate cement. CONCLUSIONS: 1. The immediate and early clinical results of our study suggest that treating reversible pulpitis with 5% KNO3 in polycarboxylate cement has an a very good analgesic action 2. The normal electrical excitability of the treated teeth is restored faster than that in the teeth treated by calcium hydroxide-based materials (P < 0.001).

An in vitro study of the released potassium and chloride ions from polycarboxylate cement containing 5% KCl.

AIM: To find with a laboratory study in vitro the concentrations of released potassium (K+) and chloride (Cl-) ions extracted from polycarboxylate cement containing 5% KCl. MATERIAL AND METHODS: Model calibrated blocks of polycarboxylate cement containing 5% KCl were prepared for the study. Every block contained 6.40 mg potassium ions and 5.80 mg chloride ions. The extraction of the ions was performed in stationary conditions with extragent Aqua redestillata at different time periods: 20 minutes from the mixing of the cement, 24 h, 7 days/168 h/, 14 days/336 h/, 30 days/720 h/ and 90 days/2160 h/ at temperature 36 +/- 0.5 degrees C and pH--7. The concentrations of the released K- and Cl- ions in the extract (in mg/10 cm3), as well as their degree of extraction (in percentage) were measured using emission flame photometry and spectrophotometry. The data are analyzed statistically using descriptive statistics, statistical significance being defined at p<0.05. RESULTS: The concentrations of released potassium and chloride ions increased with time and reached their maximum on the 14th day (336 h). The differences with their respective baseline values are statistically significant (P<0.001). The degree of extraction of the active ions is highest on the 14th day (336 h) - (93.12% for the K-ions and 93.10% for the CL-ions). CONCLUSION: The active supplement of 5% KCL in the polycarboxylate cement increases the rate of extraction of the ions, as the concentrations of the released K- and Cl-ions increase with time and reach maximum values on the 14th day (336 h).