REFERENCES 1. Keresztesi, K., Kellner, G.: Biological Effect of Root Filling Materials. J. Fed. Dent. Int. 16:222, 1966 2. Rappaport, H., Lilly, G., Kapsimalis, P.: Toxicity of Endodontic Filling Materials. O.S.O.M.O.P. 18:785, 1964 3. Kawahara, H., Yamagami, A., Nakamura, M.: Biological Testing of Dental Materials by Means of Tissue Culture. J. Fed. Dent. Int. 18:443, 1968 4. Spangberg, L.: Biological Effects of Root Canal Filling Materials. Odont. Revy 20:6, 1969 5. Spangberg, L.: Effect of Solubilized Root Canal Filling Material on HeLa Cells. Odont. Revy 20:4, 1969 6. Spangberg, L.: Effect in vitro of Water Soluble Components of Root Canal Filling Material on HeLa Cells. Odont. Revy 20:2, 1969 7. Spangberg, L.: Toxic Effect in vitro of Root Canal Filling Materials on HeLa Cells and Human Skin Fibroblasts. Odont. Revy 20:5, 1969 8. Kuriowa, K.: Experimental Study on Root Canal Filling Using a New Filling Material N2 and AN2. Bull. Oral Path. 4:45, 1960 9. Snyder, D., Seltzer, S., Moodnik, R.: Effects of N2 in Experimental Endodontic Therapy. O.S.O.M.O.P. 21:635, 1966 10. Langeland, K., Guttuso, J., Langeland, L.; Tobon, G.: Methods in the Study of Biologic Responses to Endodontic Materials, Tissue Response to N2. O.S.O.M.O.P. 27:522, 1969 11. Engstrom, B., Spangberg, L.: Effect of Root Canal Filling Material N2 When Used for Filling After Partial Pulpectomy. Sven, Tandlak. Tidskr. 62:815, 1969 12. Asano, S.: Clinico-Pathological Study of Direct Pulp Capping and Immediate Root Canal Filling after Vital Pulp Extirpation with N2 and Calvital. Shikwa Gakuho 73:989, 1973 13. Muruzabal, M.: Process of Healing Following Endodontic Treatment in Molar of Rat. Proceedings of Fifth Intern'l Conf. on Endodontics, U. Pennsylvania, 1973 14. Feldmann, G., Nyborg, H., Conrado, C.: A Comparison Between Implants of the Root Filling Material N2 and Silver in the Jaws of Rabbits. Odont. Revy 17:387, 1966 15. Spangberg, L.: Reaction of Bony Tissue to Implanted Root Canal Filling Material in Guinea Pigs. Odont. Revy 20:7, 1969 16. Friend, L.: Browne, R.: Tissue Reactions to Some Root Filling Material Implanted in the Bone of Rabbits. Arch. Oral Biol. 14:629, 1969 17. Brewer, D.: Histology of Apical Tissue Reaction to Overfill. J. Calif. Dent. Assoc. 3:58, 1975 18. Harndt, R., Kaul, A.: Untersuchungen unber den Verbleib des Bleies im Wurzelkanalfullmaterial N2. Dtsch. Zahnarztl. Z. 28:580, 1973 19. Shapiro, I., Iaquinta, S., Grossman, L.: Lead Determination in Blood of Monkeys from N2. J. Endo. 9:294, 1975 20. Oswald, R., Cohn, S.: Systemic Distribution of Lead from Root Canal Fillings. J. Endo. 1:59, 1975 21. Lawrence, C., Block, S.: Disinfection, Sterilization and Preservation. Chapts. 32, 41. Lea & Febiger, Phila., 1965 22. Spangberg, L.: Biologic Effects of Root Filling Materials Effect on Bone Tissue of Two Formaldehyde Containing Pastes: N2 and Rieblers Paste. O.S.O.M.O.P. 38:934, 1974 CURRICULUM VITAE OF HOWARD MARTIN, D.M.D., F.A.C.D. Practice.-Limited to Endodontics, at 909 Pershing Drive, Silver Spring, Md., 1234 19th Street, N. W., Washington, D.C. Education.-Hobart College; Tufts University, School of Dental Medicine, D.M.D.; and University of Pittsburgh, School of Dentistry; Certificate in Endodontics. Board Certification.-Diplomate, American Board of Endodontics. University affiliation.-Professorial Lecturer in Endodontics, School of Dentistry, Georgetown University; Lecturer, Post Graduate Endodontics, School of Dentistry, University of Pittsburgh. Hospital Affiliation.-Consulting Endodontist, Department of Oral Surgery, George Washington University Hospital; Staff Endodontist, Prince George's General Hospital and Medical Center; Consulting Endodontist, Outpatient Clinic, Professional Organizations.-American Dental Association; American Association of Endodontists; Maryland State Dental Association; District of Columbia Dental Society; Academy of Dental Medicine; Academy of General Dentistry; Southern Maryland Dental Society; Maimonides Dental Society, Washington, D.C.; American Academy of Dental Electrosurgery; and Federation Dentaire Internationale. Publications "Endodontics on the Primary Dentition: Its Current Status", Georgetown Dental Journal, December, 1966. "Permeability of the Apical Third of the Root to Drugs used in Endodontic Therapy: An In Vitro Study", J. Oral Therapeutics and Pharmacology, May, 1968. "An Evaluation of Media Used in Electric Pulp Testing", Oral Surgery, Oral Medicine & Oral Pathology, March, 1969. "Basic Corrective Endodontics", J. Maryland State Dental Association, April, 1970. "Rationale of Successful Endodontics", J. District of Columbia Dental Society, December, 1970. "Telescope Technique for Endodontics", J. District of Columbia Dental Society, June, 1974. "Quantitative Bacteriologic Evaluation of an Old and a New Endodontic Irrigant", J. Endodontics, May, 1975. "Ultrasonic Disinfection of the Root Canal", accepted, Oral Surgery, Oral Medicine & Oral Pathology. "Connective Tissue Reactions to Endodontic Irrigants", in preparation. "Ultrasonic Sterilization of Dental Instruments", in preparation. Clinical presentations.-Pennsylvania Dental Society, 1965; Maryland State Dental Association, 1966; Maryland State Dental Association, 1967; American Dental Association, 1967; District of Columbia Dental Society, 1967; Maryland State Dental Association, 1968; Southern Maryland Dental Society, 1968; Virginia State Dental Association, 1968; District of Columbia Dental Society, 1968; Maryland State Dental Association, 1969; Southern Maryland Dental Society, 1969; American Dental Association, 1969; Southern Maryland Dental Society, 1970; American Association of Endodontists, 1970; Southern Maryland Dental Society, 1971; Alpha Omega Dental Fraternity, Washington, D.C., 1972; District of Columbia Dental Society, 1975; and Maryland State Dental Association, 1975. Military-Ensign, U.S. Naval Dental Corp, 1960–1962; Lieutenant, U.S. Naval Dental Corps, active duty, 1962-1964; Lieutenant, U.S. Naval Dental Corps, active reserve, 1964-1966; Lieutenant Commander, U.S. Naval Dental Corps, active reserve; and Administration and Training Officer, Georgetown Dental School Unit, 1966-1970. COMMITTEES Maryland State Dental Association.-Program, 1969; Newsletter, 1971-1973 (endodontic consultant). Southern Maryland Dental Society.-Scientific Editor, 1968-1971, 1972-1973; Public Relations, 1968-1970; and Program Chairman, 1975-1976. District of Columbia Dental Society.-Scientific Editor, 1972-1973; Program, 1973; Spring Post Graduate Meeting, Program, 1973-1974; and Spring Post Graduate Meeting, Lunch & Learn, 1975. Maimonides Dental Society, Washington, D.C.-Executive Committee, 19671969; Treasurer, 1970; Secretary, 1971; Vice-President, 1972; President-Elect, 1973; and President, 1974. American Association of Endodontists.-Membership, 1966-1968; Ethics, 1968; Literary, 1969-1970; Honors & Awards, Chairman, 1970-1973, Advisor, 1974; International Student Awards, Chairman, 1972-1974; and Committee on Scientific Evaluation, 1974-1975. Alpha Omega Dental Fraternity.-Executive Committee, 1970-1971; and Program, Chairman, 1971-1972. Maryland Society of Endodontists.-Founding Member, 1970; Interspecialty Committee, 1974; and Program, 1975. Greater Washington Endodontic Club.-Founder, 1970; Program, Chairman, 1971; and Treasurer, 1974. Mr. FOUNTAIN. Thank you, Dr. Martin, for a forthright statement and for sharing your experience and your views. We will now hear from Dr. Stephen Cohen. Mr. BURTON. Mr. Chairman, if I may out of order, I would like to welcome Dr. Cohen, who not only lives in one portion of my district but also represents the University of the Pacific Dental School which is in another portion of the district. Dr. Cohen is very respected in our community and the University of the Pacific School of Dentistry has one of the most novel outreach programs for elderly persons. The school has minibuses available which bring people in for low cost or free dental care. I would like to welcome the doctor to Washington and to the committee. I know that his testimony will be very worthwhile and to the point. Mr. FOUNTAIN. Thank you, Mr. Burton. Dr. Cohen? Dr. COHEN. Thank you very much. I would also like to extend a note of thanks to you for giving me this opportunity to present my information to all of you. Parenthetically, I see that we are now setting up the movie screens which I had requested to augment the material which I have to present. The two Kodak carrousels will be set up because I thought it might be helpful in terms of graphic matter to effectively illustrate the points that I would like to raise. So, with your permission, if I may request it, I would like the equipment set up. Therefore, I would like to postpone my comments until Dr. Glick has a chance to present his information. If that is not reasonable at this time, I will read my prepared statement. I am amenable to whatever the committee suggests. Mr. FOUNTAIN. How long would it take you to get it up, Doctor? Dr. COHEN. I see that there are two screens over there. If the carrousels are available it would not take too long. Mr. FOUNTAIN. Perhaps Dr. Glick can go ahead with his testimony while you are engaged in that process. Dr. COHEN. Thank you very much. Mr. LEVITAS. Mr. Chairman, may I inquire whether one of the witnesses today is going to enlighten me for one as to what the process is that we are talking about. I understand that endodontics has to do with root canals but it is possible that someone other than I does not understand precisely what is involved in this whole controversy as far as the procedure is concerned. Mr. FOUNTAIN. I think Dr. Martin generally described it in his statement. Mr. LEVITAS. I followed his statement but I was left in doubt. Also, I might say that I am not familiar with all of the dramatis personae. The names that Dr. Martin referred to were just names. I wonder if they could be more fully identified. Mr. FOUNTAIN. Mr. Levitas, I could yield to you for questioning if you like at this point. Mr. LEVITAS. I would abide by the chairman's request. I followed his statement, but I am not just exactly sure what it is that is done and what these gentlemen do, other than the drugs mentioned. Mr. FOUNTAIN. I think that will be brought out in the process of questioning. Other witnesses will take up that subject. Mr. MEZVINSKY. Mr. Chairman, are we going to hear from Dr. Glick now? It was my understanding we were going to go ahead with Dr. Glick. Mr. FOUNTAIN. Yes, we will go ahead with Dr. Glick. STATEMENT OF DUDLEY GLICK, D.M.D., F.A.C.D., F.I.C.D, UNIVERSITY OF SOUTHERN CALIFORNIA SCHOOL OF DENTISTRY Dr. GLICK. Thank you, Mr. Chairman. Throughout the long history of medicine and dentistry, a procedure or drug has been periodically proposed as a panacea. After much publicity and promise, most of these so-called "miracle cures" are exposed for what they really are, exaggerated and useless. Wisely they are then discarded but unfortunately not before they have left an undesirable effect upon the profession and public. N2 is just such a self-styled miracle drug. N2 has aroused considerable controversy over the past few years, insinuating that the established endodontic techniques are outmoded. This reactionary thrust is consistent with a current onslaught against the "establishment." Rather than brush it off, let us try to evaluate some of the drug's components and some of the claims. In order to discuss the use of N2 for teeth in need of endodontic therapy, we must first define that which we are to discuss. The symbol N2, as currently used, can refer to either a material, which is a paste used to seal root canals, or to a technique for treating endodontically involved teeth employing N2 paste as a root canal filling material. This type paste is not "new, revolutionary, or brilliant," as Sargenti so unabashedly describes it. It has precedent as far back as 1870— Walkoff's Paste-and 1900-Gysi's Paste. In fact, Sargenti's paste is based on a 50-year old formula, Robin's Paste. They were found inadequate and wanting and so fell into disrepute. Not until a predictable technique and solid-core filling material was utilized have we been able to retain teeth safely, comfortably, and with longevity. Parenthetically, the N2 method is not taught at any of Switzerland's four dental schools. The formula for N2 paste is a variation of a zinc oxide-eugenol root canal cement. However, it differs from the usual zinc oxide-eugenol formulation inasmuch as it contains a corticosteroid, lead oxide, an antibiotic, para formaldehyde, and a coloring and deodorizing agent. The quantities of each of these ingredients tend to vary from batch to batch. This information was developed and has been attested to by both the Food and Drug Administration of the United States of America and by the Commonwealth Bureau of Dental Standards of Australia. The originator of the N2 formula, Dr. Angelo Sargenti, claims that the material is not resorbable and is well tolerated by the periapical tissues. At other times he maintains that it is resorbable. We know, however, that zinc oxide-eugenol pastes are resorbable as is demonstrated by the gradual radiographic disappearance of zinc oxide-eugenol cements which are displaced into the periapex or around the end of the root. Langeland has demonstrated that within minutes after application of N2 to the periapical tissues macrophages-these are cells that go in and ingest and take away irritants-will start to ingest the lead oxide. Shortly afterwards, this lead can be traced to the liver where the body attempts to detoxify it. The hepatic damage, which can occur as the result of the introduction of heavy metals into the body, can be considerable. The significance of the introduction of even a small amount of lead into body tissues must be given greater concern today as we are assaulted from all corners of our environment by substances which have the potential for liver damage. [See Shapiro in the references.] The incorporation of an antibiotic in any material to be placed inside a root canal has been a questionable practice and a subject for debate. The possibility for sensitivity reactions is always present. All too often dentists tend to look upon inflammation as a detrimental process or at least, a hindrance. We lose sight that inflammation is one of the ways an organism combats infection or irritation. The inflammatory response results in a walling off of the instigating agent. This having been accomplished, the body can use its defenses most economically. The use of any anti-inflammatory agent such as a corticosteroid greatly enhances the possibilities of widespread dissemination of noxious material. Paraformaldehyde may react in the presence of moisture to form formaldehyde. We are well aware of the toxic effects of formaldehyde on vital tissue. Consider the possibility of the mandibular root whose apex approximates the mandibular nerve or the maxillary root whose apex has little or no bone between it and the sinus membrane. Reports of parasthesia (numbness) of the mandibular nerve in conjunction with the use of N2 do appear in the literature. There is clinical evidence to show that instances of sinus damage have occurred. Sargenti, in his text, shows as an example of the body's tolerance of his material, slides in which a hard tissue or cemental bridge sealing the apex of a tooth treated with N2 is seemingly present. This is not even a clever sham, as it only involves choosing a poorly representative section. Langeland, a noted dental histopathologist and authority on the serial sectioning of teeth and periapical tissue, has yet to demonstrate a single apex which has been completely sealed by hard tissue. He has found that there are always areas where the bridging is incomplete and soft tissue remains. N2, as a philosophy of endodontic treatment, is more difficult to define. This difficulty exists primarily because Sargenti's advocates have taken him too literally, and his books contain many inconsistencies. He has made many claims for his wonder drug. Although Sargenti writes about complete debridement of the canal, he vocally implies that his material is so effective that it will take care of whatever tissue is left behind. One can readily see how this can be distorted to the point where the majority of the canal contents are left untouched, particularly where the emphasis is placed on simplicity and rapidity. Often little more is done than a pulpotomy-and this means just cleaning 62-841 O-76-3 |