The endodontic cube: a system designed for evaluation of root canal anatomy and canal preparation.

An extensively redesigned muffle system is presented incorporating improved design features, such as rigid external fixation and machined internal indexing to enable a more accurate, clinically relevant, and reproducible evaluation of root canal anatomy before and after preparation. Given the ability to directly observe and quantify changes in the root canal system, the information obtained using this design is comprehensive. In each tooth pretreatment evaluation provides the ideal control, reinforcing the suitability of this technique.

Effect of various sealers with gutta-percha as root-end fillings on healing after replantation.

This study examined histologically the effect of three sealers used with gutta-percha as root-end fillings placed in a replantation model. A total of 14 molar teeth were used in seven monkeys. After extraction, root ends were resected, the canals contaminated with oral bacteria, root-end cavities prepared, and fillings of gutta-percha and sealer placed prior to replantation. After 8 weeks the teeth and surrounding jaw were removed and prepared for histological examination. Six roots filled with gutta-percha plus a fortified zinc oxide-eugenol cement (IRM), 13 with gutta-percha plus zinc oxide-eugenol (EP), and eight with gutta-percha plus Kloropercha, were available for examination. The tissue response to gutta-percha with either zinc oxide material was characterized by little or no inflammation of limited extent. In contrast, more severe inflammation was observed against root ends filled with gutta-percha and Kloropercha. Gutta-percha plus IRM or zinc oxide-eugenol had a much more favourable response than that to amalgam reported previously in a similar experiment.

Effect of various zinc oxide materials as root-end fillings on healing after replantation.

This study examined the effect of various zinc oxide materials as root-end fillings of teeth in a replantation model. A total of 35 molar teeth were used from 19 monkeys. After extraction, root ends were resected, the canals contaminated with oral bacteria, root-end cavities prepared and fillings placed prior to replantation. After 8 weeks the teeth and surrounding jaw were removed and prepared for histological examination. Twelve roots were filled with IRM plus dentine chips, and six with Cavit; the tissue response around root ends filled with these materials as assessed by inflammation was similar to that previous reported to IRM and Super EBA cement and was characterized by little or no inflammation of limited extent. In contrast, more severe inflammation was observed around root ends filled with plain zinc oxide-eugenol or Kalzinol; however, the reaction was neither as severe nor as extensive as that to amalgam root-end fillings. Giant cells were observed most often on the surface of fillings with Cavit and zinc oxide-eugenol. It is concluded that the tissue response to IRM with or without added dentine, Super EBA and Cavit was similar and mild; it was less severe than that to zinc oxide-eugenol and Kalzinol. All these materials had a much more favourable response than amalgam

Effect of super-EBA as a root end filling on healing after replantation.

The effect of Super-EBA cement as a root-end filling placed in teeth before replantation was examined in eight molar roots in monkeys. After extraction, root ends were resected, the canals contaminated with oral bacteria, root-end cavities prepared, and fillings of Super-EBA placed before replantation. After 8 wk, the jaws were removed and prepared for histological examination. The tissue response to Super-EBA was very mild, with only a few inflammatory cells being observed at the root end of 3 of the 8 roots filled. Previous work showed a similarly mild response to Intermediate Restorative Material and a very much more severe response to amalgam. It is concluded that the tissue response to Super-EBA as a root-end filling is acceptable and considerably more favorable than that to amalgam.

Effectiveness of various medications on postoperative pain following root canal obturation.

This prospective study compared the effectiveness of nine medications and a placebo in controlling pain following obturation. A total of 588 patients who required root canal obturation were included. After obturation of root canals, each patient took one of the medications, salicylic acid (2 x 250 mg), acetaminophen (2 x 250 mg), ibuprofen (2 x 250 mg), ketoprofen (2 x 250 mg), acetaminophen (2 x 250 mg) plus codeine (2 x 250 mg), penicillin (2 x 250 mg), erythromycin base (2 x 250 mg), penicillin plus ibuprofen (2 x 250 mg), methylprednisolone (2 x 250 mg) plus penicillin (2 x 250 mg), or a placebo, every 6 h for 72 h. All medications were encapsulated in identical capsules. The patients registered their degree of discomfort on a visual analogue scale of 0 to 9. Statistical analysis of the data showed that the incidence of postoperative pain after obturation is lower than that following complete cleaning and shaping (5.83% versus 21.76%). In addition, there was no significant difference between the effectiveness of the various medications and placebo tablets in controlling postoperative pain following obturation.

Effect of IRM root end fillings on healing after replantation.

The effect of IRM as a root end filling placed in teeth prior to replantation was examined in 21 molar teeth in monkeys. After extraction, root ends were resected, the canals contaminated with oral bacteria, root end cavities prepared, and fillings of IRM or amalgam placed prior to replantation. After 8 wk the jaws were removed and prepared for histological examination. Bacteria were demonstrated in only 9 of 15 teeth filled with IRM; 18 of the roots (60%) were associated with inflammation, which was only moderate or severe around 5 (17%), and extended > 0.1 mm around only 2 roots. In contrast, of the 6 teeth filled with amalgam, all contained bacteria in the root canals and 11 roots were associated with moderate or severe inflammation, which around 8 roots extended > 0.5 mm. The difference in severity of inflammation for the two materials was statistically significant (p < 0.001). The tissue response to root end fillings of IRM in replanted teeth was less severe and less extensive than that to amalgam.

Advances in endodontic surgery.

Periradicular surgery is now increasing in importance as practitioners increase their knowledge and skill in saving teeth that were previously extracted. Many advances have occurred in recent years in both technique and materials. Tissue flaps should be designed with vertical releasing incisions and a wide base for optimal access and more rapid healing. Increased lighting and magnification now provide enhanced surgical vision. New root-end filling materials, such as SuperEBA and IRM, may reduce apical leakage and increase the percentage of successful surgical cases. Improvements in suture materials and postoperative techniques produce a more predictable and more comfortable course of healing for the patient.

Surgical endodontic and retrograde procedures.

This article reviews the recent literature on endodontic surgery and root end filling materials. Root end filling materials have been studied extensively during the period of this review. The materials that have proved to consistently seal the apex in both leakage and success studies are the reinforced zinc oxide-eugenol cements such as IRM (The L.D. Caulk Co., Milford, DE) and SuperEBA (Harry J. Bosworth Co., Skokie, IL) cement. Articles on treatment planning and surgical armamentaria are also reviewed. Two textbooks and 21 journal articles are cited.

Retrograde filling materials: a retrospective success-failure study of amalgam, EBA, and IRM.

A retrospective study was done to compare the success rates of teeth with three different root end filling materials. The materials studied were SuperEBA, IRM, and zinc-free high-copper spherical amalgam. Radiographs of 488 cases from two geographically distinct offices were used, with the recall period ranging from a minimum of 6 months to a maximum of 10 yr. The cases in each office were examined independently using the same criteria. The results revealed that both SuperEBA and IRM demonstrated statistically significant improvements in success rates when compared with amalgam. The success rates were 75% for amalgam, 91% for IRM, and 95% for SuperEBA. The difference between IRM and SuperEBA was not statistically significant.

Treatment of the endodontic emergency: a decade later.

A questionnaire was sent to diplomates of the American Board of Endodontics to determine changing trends in the treatment of endodontic emergencies since Dorn's survey 10 yr ago. There is a definitely greater trend toward complete instrumentation of the root canals to the apex regardless of the emergency condition than there was a decade ago. The number of respondents who leave teeth open when the pulp is nonvital has dropped dramatically in the past decade. When there is no periapical involvement, over one third of the respondents are completing treatment in one visit. A decrease in the use of classic phenolic medicaments was noted with a corresponding increase in calcium hydroxide or no medication at all.