Thermal response to multiple use of a twist drill.

The objective of the present investigation was to determine whether injurious thermal changes occur in the pulp chamber if a twist drill is used 10 times, and to find whether there is a correlation between temperature rise and distance between a drilled channel and the pulp chamber. Twenty caries-free, human, premolar teeth were randomly distributed to two dentists. With a new 2 mm twist drill, each dentist prepared 10 pinholes (one hole per tooth). Intrapulpal temperature change during the drilling procedure was recorded. The data were statistically analyzed by the Spearman rank order correlation coefficient. The results showed that twist drills should not be used for more than five pinholes (p less than 0.001). The distance between the pin channel and the pulp chamber does not influence heat generation in the pulp chamber.

[Intrapulpal temperature change during the setting reactions of various dental cements]. / Simanlarin sertlesme reaksiyonlari esnasinda pulpada olusturduklari isi degisimleri.

Mixing of certain types of dental materials may produce pulpal injury due to a series of chemical reactions giving way to an exothermic reaction. Three different dental cements; zinc phosphate, polycarboxilate and glass ionomer cements which may increase the intrapulpal temperature were investigated in the present study. The cements were mixed according to the manufacturers' instructions in one group, the liquid and powder ratios were increased by one portion in the other two groups. The intrapulpal temperature changed between 1.32-4.54 degrees C among the three test groups. The intrapulpal temperature rise was markedly influenced when the amount of powder and liquid ratios were changed.

[PH changes of different cements]. / Cesitli simanlarin PH degisimi.

Some properties are required in dental cements used in fixed restorations. One of them is the acidic characteristic of the material since (OH)- ions released during the setting phase may have undesirable effects on the pulp. In this study three different luting cements were tested regarding to their PH values during setting reaction and was found that cements used caused PH changes. Acidity of cements had changed considerably depending upon time and it was determined that PH values of three cements decreased in the period of 24 hours.

[Heat changes in the gingival region of both upper and lower incisor-bicuspid and molar teeth: comparative study of healthy persons and patients who have gingivitis]. / Gingivitisli ve saglikli bireylerde üst ve alt çene keser-küçük azi ve azi disleri diseti sahalarindaki isi degisimleri.

In this research, total of 12 persons, 7 women and 5 men, 21-24 ages were tested. Gingival index, Greene and Vermilion simplified oral hygiene index and sulcus depth measurements were determined for both groups, local heat changes were measured in upper and lower vestibular, lingual and or palatinal keratinized gingival mucosa. According to the results, in the patient group, upper heat levels were found higher than lower levels. But only in the anterior region, the difference was statistically significant (p less than 0.05). Local heat changes were found higher in the patient group than the control group for all areas but the difference was not statistically significant.