Daniel Kempler

Human blood pressure and pulse rate response to racemic epinephrine retraction cord

1. The pulse rate of patients after application of racemic epinephrine-impregnated retraction cords depends more on the level of anxiety and stress than on the level of the epinephrine. 2. Blood pressure is elevated by placement of racemic epinephrine-impregnated retraction cords upon an exposed vascular bed or lacerated tissue. 3. Four percent racemic epinephrine-impregnated retraction cords cause less elevation of blood pressure than 8% racemic epinephrine cords. 4. Although the elevations in blood pressure from 8% cord occur within a narrow range, this range may be hazardous to cardiac patients. Therefore, 4% racemic epinephrine cord should be used. 5. A desirable amount of tissue retraction is produced by 4% racemic epinephrine cord. 6. Dry cords do not provide adequate retraction of tissue and are contraindicated for tissue-retraction purposes.

Technical note: Antimicrobial action of glass-ionomer lining cement on S. sanguis and S. mutans

There are a number of glass-ionomer lining cements available to the profession. It is generally agreed that the glass-ionomer cements demonstrate reasonably good biocompatibility. The purpose of this study was to evaluate the antimicrobial activity of six glass-ionomer cements on S. sanguis and S. mutans. Forty-eight plates of TSA-SRBC (10%), each with 3.0-mm-diam. wells, were divided into two groups (1 and 2) of 24 each. Group 1 was inoculated with S. sanguis (10558) and Group 2 with S. mutans (6715-13 w.t.). Each well was filled with 4.0 mg of one of the following liners: Glassic (A), Shofu lining cement (B), GC lining cement (C), Ever Bond (D), Gingiva Seal (E), and Ketac Bond (F); the empty wells served as control. Plates were incubated under microaerophilic conditions at 37 degrees C, and checked daily over seven days for inhibition zones. Average inhibition zones (mm) at 7 days were as follows: Group 1-1A = 10.00, 1B = 7.83, 1C = 18.50, 1D = 13.00, 1E = 8.67, and 1F = 9.33; Group 2-2A = 3.08, 2B = 10.25, 2C = 12.75, 2D = 15.58, 2E = 8.83, and 2F = 3.20. All control wells were 0.0 GC liner and Ever Bond showed significantly greater overall inhibition of microbial growth than did other tested liners (p less than 0.5). A one-way ANOVA and SNK test showed that all tested liners were significantly more toxic toward S. sanguis than toward S. mutans (p less than 0.05).

Laser Evaluation of Handpiece Contamination

Six different models of ultra-high speed handpieces were evaluated in regard to debris accumulation following cutting through tooth structure. A weight-load machine and a laser particle detector were utilized to evaluate the amount of the debris retained. Amounts of debris accumulated after dry and wet cutting were also evaluated. The effect of simple wiping of the handpieces with alcohol gauze was assessed. The results obtained show that the longer the cutting time, the larger the amounts of debris retained on the handpieces. Dry cutting resulted in smaller amounts of debris entrapped than following wet cutting. The cleaning by wiping with alcohol gauze reduced the amounts of the debris, but is insufficient and cannot be utilized as a single procedure for decontaminating handpieces. The external head design is a cardinal factor in retention of debris: larger but smoother surfaces will retain less debris than smaller but more complicated surfaces. External tubings are debris retention foci.

Clinical and Materials Sciences The Effects of Retraction Cords and Electrosurgery upon Blood Pressure and Tissue Regeneration in Rhesus Monkeys

evices were used for gingival retraction prior to impression-taking procedures. The effects of these retraction methods upon blood pressure and loss of gingival tissue height were evaluated on three Rhesus monkeys. Chamfer finishing lines were prepared on all of the teeth and penetrating into the gingival sulcus. All the retraction devices were used to produce the desired amount of retraction which would allow an acceptable impression. Contralateral teeth, on which a chamfer was cut but no retraction performed were used as control teeth.The only retraction device which had no effect on blood pressure and caused no tissue loss was the nonepinephrine retraction cord. The 8% r-epinephrine string and the two electrosurgical devices caused elevated blood pressures. With the 8% r-epinephrine retraction cord, no tissue loss was observed and complete healing occurred within nine days. Both electrosurgical devices caused tissue loss. The fully rectified current device caused a slight loss in gingival tissue height...evices were used for gingival retraction prior to impression-taking procedures. The effects of these retraction methods upon blood pressure and loss of gingival tissue height were evaluated on three Rhesus monkeys. Chamfer finishing lines were prepared on all of the teeth and penetrating into the gingival sulcus. All the retraction devices were used to produce the desired amount of retraction which would allow an acceptable impression. Contralateral teeth, on which a chamfer was cut but no retraction performed were used as control teeth. The only retraction device which had no effect on blood pressure and caused no tissue loss was the nonepinephrine retraction cord. The 8% r-epinephrine string and the two electrosurgical devices caused elevated blood pressures. With the 8% r-epinephrine retraction cord, no tissue loss was observed and complete healing occurred within nine days. Both electrosurgical devices caused tissue loss. The fully rectified current device caused a slight loss in gingival tissue height, while the spark gap generator caused a marked amount of tissue height to be lost. The Hyfrecator should not be used for gingival retraction because of the tissue damage that results. It appears that the safest retraction device is the retraction cord, when used properly. Further research is recommended to establish the possible systemic effects of the electrosurgical techniques.

A comparison between xeroradiography and conventional radiography in the diagnosis of endodontic lesions

Detection of periapical bone pathosis is an important part of the diagnostic process in dentistry. Xeroradiographs and E-speed films were taken to evaluate and to compare the diagnostic value for the radiographic interpretation of periapical lesions. Thirty-four patients undergoing endodontic treatment were chosen. Simultaneous exposures of the radiographic film and the xeroradiographic plates were made. The samples were viewed and categorized by the examiners using the following scores: 0 = unacceptably poor, 1 = poor but diagnostic, 2 = adequate for diagnostic information, and 3 = optimal for diagnostic information. A paired sample t test was performed on the result of the evaluation by the two examiners, and both showed that there were no significant difference at p less than 0.05 between xeroradiography and conventional radiography. A two-sample t test was performed on the means of the two examiners evaluation, and there was no significant difference at p less than 0.05 between the means.

Antimicrobial activity of calcium hydroxide liners onStreptococcus sanguis andS. mutans

The antimicrobial activity of 10 calcium hydroxide liners on Streptococcus sanguis and S. mutans was studied. One hundred plates of tryticose soy agar-sheep red blood cells (10%), each with four distinct 3 mm diameter wells, were divided into two groups of 50. One group was inoculated with S. sanguis and the second group with S. mutans. A 4 mg liner was placed in each of three wells; the fourth well was left empty as a control. Plates were incubated at 37 degrees C and observed at 24 hours, 48 hours, and 7 days. All liners inhibited growth of both organisms. The inhibitory zones for S. mutans were larger than inhibitory zones for S. sanguis for all tested liners. Life Fast Set material had significantly less inhibitory effect on S. mutans. VLC Dycal, Life, and Life Fast Set materials had significantly less inhibitory effect on S. sanguis at p = 0.05.

Mesiodistal root fracture: Three case reports

Vertical root fractures present a complex diagnostic problem. Three cases of vertical root fractures are presented. In the first case, there was a mesiodistal vertical fracture with an almost intact tooth structure. In the second case, there was a mesiodistal vertical fracture with an extensive amalgam restoration and improper root canal treatment. The third case showed extensive root caries with proper root canal therapy. All of the cases resulted in periodontal defects with subsequent loss of the tooth. Diagnosis was obtained with the use of clinical, fiberoptic, and disclosing solution examinations. Histologic examination revealed pulpal canals devoid of vital tissue and filled with necrotic material, debris, neutrophils, and bacterial colonies.