Seymour Oliet

Single-visit endodontics: A clinical study

Summary A clinical study was conducted to compare single-visit and two-visit endodontic procedures. Under controlled circumstances including accurate diagnosis, proper case selection, and skilled treatment technique, single-visit treatment postoperative sequelae and healing did not differ significantly when compared with two-visit procedures.

Cutting efficiency of endodontic reamers

Abstract The cutting efficiency of endodontic reamers was evaluated with a testing apparatus developed especially for the study. Bovine bone was used to simulate dentin because of its structural and chemical similarity to dentin. Triangular reamers cut more efficiently than did square reamers, but had a higher failure rate. Instrument failure resulted from deformation or fracture of the blade rather than from wear. Commercially available instruments exhibitd wide variations in quality, sharpness of cutting edges, cross-sectional configuration, and number of flutes.

Evaluation of culturing in endodontic therapy: A preliminary clinical report☆

Abstract 1. 1. A preliminary clinical study of ninety-eight endodontic cases was completed in an effort to evaluate the use of a culturing technique in endodontic therapy. 2. 2. A greater degree of success in healing occurred when teeth were filled with no evidence of microorganisms in the root canals. 3. 3. A proper culturing technique should be used routinely by the dentist in order to obtain the most favorable prognosis possible for his patient.

Treating vertical root fractures

Three case histories are presented describing a different method for treating vertical root fractures. The technique consisted of extraction of all fractured segments, completion of all endodontic procedures extraorally, recementation of segments with cyanoacrylate, banding, and replantation with ligation within 30 min. Although most of these teeth are still comfortable and functional, the long-term prognosis remains poor.

Effect of aging on the mechanical properties of hand-rolled gutta-percha endodontic cones

This study examined the effect of storage, for periods varying up to 24 weeks and at temperatures from -12 degrees C. to 50 degrees C., on the compression, tension, torsion, and bend properties of size 100 hand-rolled gutta-percha cones. All of the properties changed during storage, with the largest changes occurring at the highest temperatures, the smallest changes occurring at the lowest temperatures, and the greatest rate of change occurring during the initial 40- to 60-day storage period. All of the cones tested were subjectively found to be clinically usable. Since ideal characteristics or standards for mechanical properties are nonexistent, assessment of the changes is speculative and arbitrary. The condition of cones at which clinicians decide they are unusuable also varies widely. Continual study of this problem is indicated and important.

Torsional tester for root canal instruments

Abstract We have described equipment developed for measuring the torsional properties of instruments from initial stress to fracture. Special holders were utilized for both ends of the instruments. Torque was accurately applied by the dropping of water to rotate a shaft which was supported so that only the twisting force was used on the instrument. The amount of instrument distortion was indicated by measurement of shaft rotation. Test results showed that the methods of gripping the instruments and measuring torque were satisfactory. Although data are given for all instruments tested, no conclusion can be drawn because of the preliminary nature of the work.

A temperature analysis of thermostatically controlled root canal sterilizers using molten metal, glass beads, or salt.

Abstract 1. A temperature analysis was done on three sterilizers using molten metal, glass beads and salt by means of the apparatus shown in Fig. 1. 2. The order of efficacy of heat conduction appears to be: molten metal, salt, glass beads. 3. Salt exhibits certain practical advantages over molten metal and glass beads for the less experienced operator. 4. A definite gradient of temperature exists between the base and surface of all sterilizers, and between the outer circumference of the well and the center of the well in sterilizers using solid heat-conducting media. 5. Substitution of salt or glass beads into wells designed for molten metal appears to be contraindicated unless an approximate temperature of 425° to 475° F. can be attained. 6. A narrow deep well is preferable to a wide shallow well when solid heat-conducting media are used in a thermostatically controlled sterilizer. 7. Instruments to be sterilized should be inserted as deep as possible near the sides of the well when sold heat-conducting media are used.

Evaluation of methods for sterilizing root canal instruments.

Abstract 1. 1. Molten metal at 425° F. for ten seconds will destroy all forms of organisms which are commonly found in root canals. 2. 2. Glass beads, extrafine, at 425° F. for ten seconds will destroy all forms of organisms which are commonly found in root canals. 3. 3. Hot air, at its present maximum temperature of 394° F., is effective against vegetative forms but not against spore forms within ten seconds. 4. 4. Mechanical cleansing of endodontic instruments prior to their sterilization was found to be as important as the method of sterilization itself. 5. 5. Chemical sterilization was found to be uncertain in its effect upon the various types of microorganisms found in root canals. Some of the chemical solutions were found to be caustic or had an objectionable odor. 6. 6. Clinically, glass bead sterilization has several advantages over molten metal sterilization, namely: there is no dross formation; no antiflux is needed; no blockage of canals occurs; and there is less danger of serious burns through spillage, as the beads do not cling to skin or clothing. The disadvantages of glass bead sterilization are that glass beads require as much time as molten metal to attain initial sterilizing temperature and a close check with a thermometer is required to be certain that the proper sterilizing temperature has been reached when the sterilizer is not thermostatically controlled.

Inhibition of the corrosive effect of sodium hypochlorite on carbon steel endodontic instruments.

Sodium hypochlorite solution was quite corrosive to immersed carbon steel instruments particularly in the presence of crushed-tooth material. There was no apparent effect on stainless steel instruments under identical conditions. Dilution of the 5% sodium hypochlorite solution with 3% hydrogen peroxide solution substantially reduced the corrosivity of the solution.

Correlation of clinical diagnosis and bacteriologic status of symptomatically involved pulps

Abstract 1. 1. A total of 771 pulps were cultured aerobically, samples being taken in separate culture tubes from the coronal and radicular portions of the same pulp. 2. 2. The cultures were correlated with the clinical diagnosis in each case. 3. 3. Cultures of the coronal portion of the pulp were correlated with those of the radicular portion of the pulp. 4. 4. The data have been presented in tabular form.