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Classification of dentine into primary, secondary, and tertiary
ENDODONTICS The American
Association
Victor
Editor
.
H. Die&,
.
.
.
.
.
CLASSIFICATION
.
.
of Endodontists
.
.
OF DENTINE
.
.
.
.
.
INTO PRIMARY,
.
.
.
.
.
.
.
.
.
SECONDARY,
AND TERTIARY* Yury Kuttler,
D.D.S., M.D., Mexico, D. P.
T
HE most important function of the dental pulp is the formation of dentine with which there exists such an intimate histologic and physiologic relationship that some authors consider them as two parts of the same pulp organ. We are all aware of the existence of three distinct types of dentine, distinguished by their origin, motivation, time of appearance, structure, chemical composition, tonality, physiology, resistance, and finality. However, there exists real chaos concerning the denomination of each type. There is so much confusion that one does not always know which type is under discussion. With the purpose of ending this cotifusion, and in order to avoid future difficulty, I propose to refer to these three types as primary, secondary, and tertiary dentine. PRIMARY
DENTINE
This dentine is formed by the thickening of the basic membrane between the internal enamel epithelium and the primary mesodermic pulp. First, the network of von Korff’s fibers appear producing the first organic precollagenous This is followed by the (uncalcified) dentine that becomes the predentine. appearance of the dentinoblasts, and by a process not yet determined the calcification of the dentine starts. The dentinoblastic column begins to separate gradually and dentinogenesis advances from the incisal or occlusal portion toward the apex of the tooth forming the primary dentine (Figs. 1 and 2, D’) , which has also been referred to as primitive, initial, regular, normal, physiologic, etc. In the dentine of Presented before the Mexican Society of Endodontia, Aug. 2, 1957. *From the book entitled lndodoncio Prdctica (in preparation). 996
Volume 12 Number 8
CLASSIFICATION
OF DENTlNE
997
young persons the tubules are very numerous (15,000 to 70,000 per square millimeter), almost straight, and fairly wide, representing one-fourth of the dentine.
Fig.
L-D’,
SECONDARY
Primary
dentine;
D’,
secondary
dentine;
P,D,
predentine
: 0 odontoblasts.
DENTINE
With the eruption of the teeth, and especially with occlusal contact, the pulp begins to receive the slight aggressive effects of normal biologic function (mastication, light thermal changes, chemical irritants, and slight traumas).
KUTTLER
998
OS., O.M. & O.P. August, 1959
In my “pathogenic classification of pulp altera.tions,” these aggressions art> referred to as being of the first grade 01’ order, since they arc within t,hr threshold of pulpal resist,ancc~and easily stimulate t,hc tlcfcnsc lncchianism of Ihcl In response, tlio pulp forms intcrmittc>nt layers of serondary dcntinc pip. as compensat~ing, protective. (Figs. 1 and 2, D$), rcfcrrrd to by othc>r authors adventitious, senile, Ilol~lnal physiologic, tubular, typical, pathologic, physiopathologic, regular, regular-primary, neodentine, regular-secondary, irregular, normal-sccoIlda~v, regular-physiologic, irregular dcntine of the first order, of the second order, primary-odontohlastic, etc.
Fig.
2.-A,
Abrasion
; E, erosion; ND, dentinal metamorphosis; D’, ondary dentine ; US, tertiary dentine.
primary
dentine;
D?,
XX-
This secondary dentine is generally separated from the primary dentine by a line or demarcation zone which may or may not be very noticeable. It is less permeable and also has less dentinal tubules due to the reduction in the number of dentinoblasts per square millimeter and consequently in the number of Tomes’ fibers. It is somewhat darker in color than the primary dentine, and its tubules are more curved, sometimes angulated, less regular, and smaller in diameter. This secondary dentine is deposited over the primary one for the purpose of better defending the pulp and reducing the size of the pulp cavity. However, the floor and the roof of the pulp chamber in premolars and molars usually receive more of this deposit.
Volume 12 Number 8
TERTI4RY
CLASSIFICATION
OF DENTINE
999
DENTINE
When the pulp irritants are more intense or more aggressive (classified as second grade”) and almost reach the limit of pulp tolerance (abrasion, erosion, caries, dentinal exposure ‘by fracture or during the preparation of cavities or crowns, improper medication, and harmful filling material), there is the formation of still another type of dentine which I refer to as tertiary dentine (Fig. 2, Ds). This has also been referred to by others as pathologic, protective, secondary, adventitious, reparatorp, irregular, compensating, irregular-secondary, irregular of the third order, amorphous, irritational, physiopathologic, irregularodontoplastic, etc. This dentine differs from the aforementioned 1. 2. 3. 4. 5. 6.
types as follows:
It is localized exclusively in front of the irritated zone. The dentinal tubules are greatly irregular, even tortuous. The tubules are reduced in number or are absent. The calcification is deficient. There are cellular inclusions which convert into spaces. There is a tonality difference.
With this simple classification based on the characteristics of the three types of dentine (alt,hough there are probably more differences that may be found with the electronic microscope), it should be possible to eliminate much of the confusing terminology that exists in current dental literature. REFERENCES Patologia, Anatomia y Fisiologia Patoldgica 1. Alcayaga, 0. C., and Olazabal, R. A.: Bucodental, Buenos Aires, 1947, El Ateneo. Electron Microscopy of 2. Bernick, S., Baker, R. F., Rutherford, R. L., and Warren, 0.: Enamel and Dentin, J. Am. Dent. A. 45: 689696, 1952. The Management of Oral Disease, St. Louis, 1955, The C. V. Mosby 3. Bernier, J. L.: Company. Morphology and Incidence of Secondary Dentin in 4. Bevelander, G., and Benzer, S.: Human Teeth, J. Am. Dent. A. 30: 1075-1082, 1943. Posteruptive Changes in Maturation of Teeth, J. Am. Dent. A. 18: 2186 5. Beust, T. B.: 2192, 1931. Fundamentals of Dental Histology and Embryology Including Clinical 6. Bodecker, C. F.: Applications, New Pork, 1944, Columbia University Press. Histologia y Embriologia buco-dentaria, Buenos Aires, 1947, El Ateneo. 7. Cabrini, R.: Das moruhische Altern der Pulpa des Zahnes. Deutsche. Zahn. Ztschr. 8. Duncker. G.: 7: i428-1432, 1952.Histologia Dentaria Humana, Buenos Aires, 1953, Progrental. 9. Erausquin, J.: Plasticheskaya deyatelnost pulpii, Sovet. stomatol. 10. Feldman, G. L., and Feldman, P. I.: 4: 21-39, 1934. Revisia nekotoriii Y aoloshenivv 11. Feldman. G. L.. and Feldman. P. I.: I v uchenii o bioloauii A pulpi, So&t. stomatol. 41 7-21, 1934. Da Polpa Dentaria, ed. 3, Rio de Janeiro, 1955, 12. Filgueiras,, J., and Mello, C.: Patologia Cientrfica. Altern der Pulpa des Zahnes, Deutsche Zahn. Ztschr. 8: 42413. Fischer, G.: Das morph&he 426, 1953. 14. Fischer, G.: Biologie der Pulpa des Menschlichen Zahnes, Leipzig, 1955, Johann AmF brosius Barth. duces
*The third grade deflnite pathologic
produces light pathologic destruction of the same
alterations pulp.
of
the
pulp,
and
the
fourth
pro-
KUTTLER
0.5.. O.M. & O.P.
August. 19i’,
15. Fuentes, A. : Algunas consideraciones morfolBgicas sobre 10s canaliculos dentinariox, An. Fat. odont. Montevideo 11: 105-121, 1956. 16. Glickman, I., and Shklar, G.: Effect of Systemic Disturbanetss on the Pulp of Experimental Animals, OK.AI, RURG., ORAL MED. & ORAL PATH. 7: 550-558, 1954. 17. Hill, T. 5.: Pathology of the Dental Pulp,, J. Am. Dent, A. 21: 820-514. 1934. Secondary Dentin Formation in the Deciduous Teeth, J. Am. Dent. A. 18. Ireland, R. L.: 28: 1626-l 632. 1941. The Dental Pulp, 1). Digest 40: 48-51, 1934. 19. Kamrin, B. B.: Conservadora, Barcelona, 1937, Ed. Labor S. A. 20. Kantorowicz, A. : Odontologia Structure of 21. Kennedv. J. J.. Teuscher. G. W.. and Fosdick. L. S.: The Ultramicroscopic Enamel aid Dentin: J. A&. Dent. A. 46: 423-431, 1953. 22 Kronfeld, R. : Histopathology of the Teeth, Philadelphia, 1949, Lea & Febiger. Investigation of Root Apexes, J. Am. Dent. A. 50: 544-552, 23: Kuttler, Y. : Microscopic 1955. (Also Bol. odont. mexicano, pp. 2-16, 1955; Gaceta odont. Venezuela, pp. 97-111, 1955; Prcitesis Clinica Habana, pp. 3-8, 1956.) 24. Kuttler, Y. : Caries dentinaria profunda, Pr6tesis Clinica (Habana), pp. 6-8, 10-12, 14, 1958. 2.5. Kuttler, Alt.eraciones pulpares en general, Rev. Asoc. odont. argent. 399-403, 19.58. T.: Kuttler, \;.: Pulpitis en general, Rev. odont. Costa Rica 1: ll-15,1958. ;;; Lukomsky, I. G. : Terapevtjicheskaya Stomatologuia, Moskwa, 1905, Medguis. 28. Manley, E. R.: Rome Observat,ions on tho Dcfenxe Mechamsm of the Dental Pulp, I). Gaz. 14: 31-34, 1947. 29. Manley, E. R., Brain, E. B., and Marsland, E. A.: An Atlas of Dental Histology, ed. 2, Oxford, 1955, Rlackwell Scientific Publications. Tratado de Histologia, ed. 3, Ruenos Aires, 1952, 30. Maximow, A. A., and Bloom, W.: Ed. Labor 8. A. 31. Meyer, W.: Anatomia en el Tratado de Odontologia dc Port-Euler, Barcelona, 1943, Ed. T,abor S. A. Basel, 1953, Benno Schwabe. 32. Muller, 0. : Pulpa und wurzelbehandlung, Oral Histology and Embryology, ed. 7 (revised by I. &hour), Philadel33. Noyes, F. B.: phia, 1953, Lea & Febiger. 34. Orban B.: Oral Histology and Embryology, St. TJouis, 1944, The C. V. Mosby Company. 35. Palazz)i S . Aspcct,s histologiques de l’atrophie de la pulpe, Rev. franp. d’odontostbma;ol. 2: 55’)~.5(X. 19.55. 36. Palazzi, S.: Trattato di Odontologia, Milano, 1950, Ulrico Hoepli. 37. Palazzi. 8. : Contribut,ion svstematiauc aux Etudes sur la biologic de la Dulne et aux recherches sur les pulpopathies mktastasiques hbmatogenes y rt const’itu~ionnellrs, L’Otlontologie ‘72: il3-716, 3934. Some Physiological Data on the Human Dental Pulp, Brit. D. J. 89: 143. 38. Pincus, I’.: 148. 1950. Conductos Radiculares (la Parte), Montevideo, 1944, Rar39. Pucci, g. M., and Rcig, R.: reiro p Ramos. Recent. Contributions in Dental Histology l)p USC of the Electron Micro40. Scott, D. B.: scope, Tntrmat. D. J. 4: 64-95, 1953. Thoughts on the Physiologic Pathology of Regressive and Reparative Changes 41. Shroff, F.: in the DPntinr and Dental Pulp, ORAL SURG., ORAL Mm. & OKAL PATH. 5: 51-58, 1952. W. S. : Elcrtron Microsconc Sturlirs of 42. Rhroff. F. R.. ~~~illiamstrn. K. T.. and Rrriaud. Dentin, &.\T, SURG., ‘ORAL Mm. P; ORAI, PATH. 7: 662-670, 1954. L K. I.. Rcrtaud. TV. 8.. and Hall. 1). M.: Furthrr Elertron 43. Shroff. F. R.. \%lliamson. Micronr& StudiPs of’ Dentin?, ORAL SIJRG., ORAL MED.’ &I ORAL PATH. 3: 432-443, ----I
--
~~
Y
I
1956. Biolopv of the Dentin. Rur 46: 121-127. 1946. 44. Sicher. 77.: Riolo$ of Attrition. OVAL SIJRG., ORAT, MED. & ORAL PATH. 6: 406-412, 195.3. 45. Sicher; H.: T. M.: St,omatologuia, ed. 2, Moskma, 1951, Medgnis. 46. Starobinsky, Oral and Dental Diseases, ed. 3, Edinburgh, 1954, E. & S. Livingstone. 47. Stones, H. H.: Development of the Fibres of the Dentine Matrix. Brit. D. J. 101: 48. Symons, N. B. B.: 25h!62. 1956. 49. Takuma, S. :’ Electron Microscopy of Dental Tissues by Use of the Replica Method, D. Ahst. 2: 399-400. 19.57. 50. Thomas, B. 0. A. : L‘ Gerodontology, ’ ’ the Study of Changes in Oral Tissues Associated
With Aging, J. Am. Dent. A. 33: 207-213, 1946. J. C., and Costas, J. B.: Estudio de a Dentina dc compensacibn, Odont. Uruguaya, pp. 411-440, 1954. 22. Vorobiev, B., and Pi&t, E. K.: Osnovi anatomii, guistologii y embriologii subov y polosti rta, Berlin, 1922, Vrach. O., and Hess, W.: Lehrhuch der Konservierenden Zahnheilkunde, ed. 5, Lrip53. Walkhoff, zig, 1954, Johann Ambrosius Barth. 51. Turell,
Volume IL Number 8
CLASSIFICATION
OF DENTINE
54. Weider F. R.! &hour, I., and Mohamed, C. I.: Reparative Dentin Following Cavity Preparation and Fillings in the Rat Molars, ORAL BURG., ORAL MED. & ORAL PATH. 9: 221-232, 1956. 55. Willman, W.: Calcifications in the Pulp, Bur 34: 73-76, 1934. 56. Zander, H. A.: Physiology of the Dental Pulp, Queensland D. J., pp. 33-37, 1953-1954. 57. Zerosi, C.: Terapia Conservativa in Odonto-Stomatologia, Torino, 1955, Edizioni Minerva medica. HAMBURGO 250.
Association
Victor
Editor
.
H. Die&,
.
.
.
.
.
CLASSIFICATION
.
.
of Endodontists
.
.
OF DENTINE
.
.
.
.
.
INTO PRIMARY,
.
.
.
.
.
.
.
.
.
SECONDARY,
AND TERTIARY* Yury Kuttler,
D.D.S., M.D., Mexico, D. P.
T
HE most important function of the dental pulp is the formation of dentine with which there exists such an intimate histologic and physiologic relationship that some authors consider them as two parts of the same pulp organ. We are all aware of the existence of three distinct types of dentine, distinguished by their origin, motivation, time of appearance, structure, chemical composition, tonality, physiology, resistance, and finality. However, there exists real chaos concerning the denomination of each type. There is so much confusion that one does not always know which type is under discussion. With the purpose of ending this cotifusion, and in order to avoid future difficulty, I propose to refer to these three types as primary, secondary, and tertiary dentine. PRIMARY
DENTINE
This dentine is formed by the thickening of the basic membrane between the internal enamel epithelium and the primary mesodermic pulp. First, the network of von Korff’s fibers appear producing the first organic precollagenous This is followed by the (uncalcified) dentine that becomes the predentine. appearance of the dentinoblasts, and by a process not yet determined the calcification of the dentine starts. The dentinoblastic column begins to separate gradually and dentinogenesis advances from the incisal or occlusal portion toward the apex of the tooth forming the primary dentine (Figs. 1 and 2, D’) , which has also been referred to as primitive, initial, regular, normal, physiologic, etc. In the dentine of Presented before the Mexican Society of Endodontia, Aug. 2, 1957. *From the book entitled lndodoncio Prdctica (in preparation). 996
Volume 12 Number 8
CLASSIFICATION
OF DENTlNE
997
young persons the tubules are very numerous (15,000 to 70,000 per square millimeter), almost straight, and fairly wide, representing one-fourth of the dentine.
Fig.
L-D’,
SECONDARY
Primary
dentine;
D’,
secondary
dentine;
P,D,
predentine
: 0 odontoblasts.
DENTINE
With the eruption of the teeth, and especially with occlusal contact, the pulp begins to receive the slight aggressive effects of normal biologic function (mastication, light thermal changes, chemical irritants, and slight traumas).
KUTTLER
998
OS., O.M. & O.P. August, 1959
In my “pathogenic classification of pulp altera.tions,” these aggressions art> referred to as being of the first grade 01’ order, since they arc within t,hr threshold of pulpal resist,ancc~and easily stimulate t,hc tlcfcnsc lncchianism of Ihcl In response, tlio pulp forms intcrmittc>nt layers of serondary dcntinc pip. as compensat~ing, protective. (Figs. 1 and 2, D$), rcfcrrrd to by othc>r authors adventitious, senile, Ilol~lnal physiologic, tubular, typical, pathologic, physiopathologic, regular, regular-primary, neodentine, regular-secondary, irregular, normal-sccoIlda~v, regular-physiologic, irregular dcntine of the first order, of the second order, primary-odontohlastic, etc.
Fig.
2.-A,
Abrasion
; E, erosion; ND, dentinal metamorphosis; D’, ondary dentine ; US, tertiary dentine.
primary
dentine;
D?,
XX-
This secondary dentine is generally separated from the primary dentine by a line or demarcation zone which may or may not be very noticeable. It is less permeable and also has less dentinal tubules due to the reduction in the number of dentinoblasts per square millimeter and consequently in the number of Tomes’ fibers. It is somewhat darker in color than the primary dentine, and its tubules are more curved, sometimes angulated, less regular, and smaller in diameter. This secondary dentine is deposited over the primary one for the purpose of better defending the pulp and reducing the size of the pulp cavity. However, the floor and the roof of the pulp chamber in premolars and molars usually receive more of this deposit.
Volume 12 Number 8
TERTI4RY
CLASSIFICATION
OF DENTINE
999
DENTINE
When the pulp irritants are more intense or more aggressive (classified as second grade”) and almost reach the limit of pulp tolerance (abrasion, erosion, caries, dentinal exposure ‘by fracture or during the preparation of cavities or crowns, improper medication, and harmful filling material), there is the formation of still another type of dentine which I refer to as tertiary dentine (Fig. 2, Ds). This has also been referred to by others as pathologic, protective, secondary, adventitious, reparatorp, irregular, compensating, irregular-secondary, irregular of the third order, amorphous, irritational, physiopathologic, irregularodontoplastic, etc. This dentine differs from the aforementioned 1. 2. 3. 4. 5. 6.
types as follows:
It is localized exclusively in front of the irritated zone. The dentinal tubules are greatly irregular, even tortuous. The tubules are reduced in number or are absent. The calcification is deficient. There are cellular inclusions which convert into spaces. There is a tonality difference.
With this simple classification based on the characteristics of the three types of dentine (alt,hough there are probably more differences that may be found with the electronic microscope), it should be possible to eliminate much of the confusing terminology that exists in current dental literature. REFERENCES Patologia, Anatomia y Fisiologia Patoldgica 1. Alcayaga, 0. C., and Olazabal, R. A.: Bucodental, Buenos Aires, 1947, El Ateneo. Electron Microscopy of 2. Bernick, S., Baker, R. F., Rutherford, R. L., and Warren, 0.: Enamel and Dentin, J. Am. Dent. A. 45: 689696, 1952. The Management of Oral Disease, St. Louis, 1955, The C. V. Mosby 3. Bernier, J. L.: Company. Morphology and Incidence of Secondary Dentin in 4. Bevelander, G., and Benzer, S.: Human Teeth, J. Am. Dent. A. 30: 1075-1082, 1943. Posteruptive Changes in Maturation of Teeth, J. Am. Dent. A. 18: 2186 5. Beust, T. B.: 2192, 1931. Fundamentals of Dental Histology and Embryology Including Clinical 6. Bodecker, C. F.: Applications, New Pork, 1944, Columbia University Press. Histologia y Embriologia buco-dentaria, Buenos Aires, 1947, El Ateneo. 7. Cabrini, R.: Das moruhische Altern der Pulpa des Zahnes. Deutsche. Zahn. Ztschr. 8. Duncker. G.: 7: i428-1432, 1952.Histologia Dentaria Humana, Buenos Aires, 1953, Progrental. 9. Erausquin, J.: Plasticheskaya deyatelnost pulpii, Sovet. stomatol. 10. Feldman, G. L., and Feldman, P. I.: 4: 21-39, 1934. Revisia nekotoriii Y aoloshenivv 11. Feldman. G. L.. and Feldman. P. I.: I v uchenii o bioloauii A pulpi, So&t. stomatol. 41 7-21, 1934. Da Polpa Dentaria, ed. 3, Rio de Janeiro, 1955, 12. Filgueiras,, J., and Mello, C.: Patologia Cientrfica. Altern der Pulpa des Zahnes, Deutsche Zahn. Ztschr. 8: 42413. Fischer, G.: Das morph&he 426, 1953. 14. Fischer, G.: Biologie der Pulpa des Menschlichen Zahnes, Leipzig, 1955, Johann AmF brosius Barth. duces
*The third grade deflnite pathologic
produces light pathologic destruction of the same
alterations pulp.
of
the
pulp,
and
the
fourth
pro-
KUTTLER
0.5.. O.M. & O.P.
August. 19i’,
15. Fuentes, A. : Algunas consideraciones morfolBgicas sobre 10s canaliculos dentinariox, An. Fat. odont. Montevideo 11: 105-121, 1956. 16. Glickman, I., and Shklar, G.: Effect of Systemic Disturbanetss on the Pulp of Experimental Animals, OK.AI, RURG., ORAL MED. & ORAL PATH. 7: 550-558, 1954. 17. Hill, T. 5.: Pathology of the Dental Pulp,, J. Am. Dent, A. 21: 820-514. 1934. Secondary Dentin Formation in the Deciduous Teeth, J. Am. Dent. A. 18. Ireland, R. L.: 28: 1626-l 632. 1941. The Dental Pulp, 1). Digest 40: 48-51, 1934. 19. Kamrin, B. B.: Conservadora, Barcelona, 1937, Ed. Labor S. A. 20. Kantorowicz, A. : Odontologia Structure of 21. Kennedv. J. J.. Teuscher. G. W.. and Fosdick. L. S.: The Ultramicroscopic Enamel aid Dentin: J. A&. Dent. A. 46: 423-431, 1953. 22 Kronfeld, R. : Histopathology of the Teeth, Philadelphia, 1949, Lea & Febiger. Investigation of Root Apexes, J. Am. Dent. A. 50: 544-552, 23: Kuttler, Y. : Microscopic 1955. (Also Bol. odont. mexicano, pp. 2-16, 1955; Gaceta odont. Venezuela, pp. 97-111, 1955; Prcitesis Clinica Habana, pp. 3-8, 1956.) 24. Kuttler, Y. : Caries dentinaria profunda, Pr6tesis Clinica (Habana), pp. 6-8, 10-12, 14, 1958. 2.5. Kuttler, Alt.eraciones pulpares en general, Rev. Asoc. odont. argent. 399-403, 19.58. T.: Kuttler, \;.: Pulpitis en general, Rev. odont. Costa Rica 1: ll-15,1958. ;;; Lukomsky, I. G. : Terapevtjicheskaya Stomatologuia, Moskwa, 1905, Medguis. 28. Manley, E. R.: Rome Observat,ions on tho Dcfenxe Mechamsm of the Dental Pulp, I). Gaz. 14: 31-34, 1947. 29. Manley, E. R., Brain, E. B., and Marsland, E. A.: An Atlas of Dental Histology, ed. 2, Oxford, 1955, Rlackwell Scientific Publications. Tratado de Histologia, ed. 3, Ruenos Aires, 1952, 30. Maximow, A. A., and Bloom, W.: Ed. Labor 8. A. 31. Meyer, W.: Anatomia en el Tratado de Odontologia dc Port-Euler, Barcelona, 1943, Ed. T,abor S. A. Basel, 1953, Benno Schwabe. 32. Muller, 0. : Pulpa und wurzelbehandlung, Oral Histology and Embryology, ed. 7 (revised by I. &hour), Philadel33. Noyes, F. B.: phia, 1953, Lea & Febiger. 34. Orban B.: Oral Histology and Embryology, St. TJouis, 1944, The C. V. Mosby Company. 35. Palazz)i S . Aspcct,s histologiques de l’atrophie de la pulpe, Rev. franp. d’odontostbma;ol. 2: 55’)~.5(X. 19.55. 36. Palazzi, S.: Trattato di Odontologia, Milano, 1950, Ulrico Hoepli. 37. Palazzi. 8. : Contribut,ion svstematiauc aux Etudes sur la biologic de la Dulne et aux recherches sur les pulpopathies mktastasiques hbmatogenes y rt const’itu~ionnellrs, L’Otlontologie ‘72: il3-716, 3934. Some Physiological Data on the Human Dental Pulp, Brit. D. J. 89: 143. 38. Pincus, I’.: 148. 1950. Conductos Radiculares (la Parte), Montevideo, 1944, Rar39. Pucci, g. M., and Rcig, R.: reiro p Ramos. Recent. Contributions in Dental Histology l)p USC of the Electron Micro40. Scott, D. B.: scope, Tntrmat. D. J. 4: 64-95, 1953. Thoughts on the Physiologic Pathology of Regressive and Reparative Changes 41. Shroff, F.: in the DPntinr and Dental Pulp, ORAL SURG., ORAL Mm. & OKAL PATH. 5: 51-58, 1952. W. S. : Elcrtron Microsconc Sturlirs of 42. Rhroff. F. R.. ~~~illiamstrn. K. T.. and Rrriaud. Dentin, &.\T, SURG., ‘ORAL Mm. P; ORAI, PATH. 7: 662-670, 1954. L K. I.. Rcrtaud. TV. 8.. and Hall. 1). M.: Furthrr Elertron 43. Shroff. F. R.. \%lliamson. Micronr& StudiPs of’ Dentin?, ORAL SIJRG., ORAL MED.’ &I ORAL PATH. 3: 432-443, ----I
--
~~
Y
I
1956. Biolopv of the Dentin. Rur 46: 121-127. 1946. 44. Sicher. 77.: Riolo$ of Attrition. OVAL SIJRG., ORAT, MED. & ORAL PATH. 6: 406-412, 195.3. 45. Sicher; H.: T. M.: St,omatologuia, ed. 2, Moskma, 1951, Medgnis. 46. Starobinsky, Oral and Dental Diseases, ed. 3, Edinburgh, 1954, E. & S. Livingstone. 47. Stones, H. H.: Development of the Fibres of the Dentine Matrix. Brit. D. J. 101: 48. Symons, N. B. B.: 25h!62. 1956. 49. Takuma, S. :’ Electron Microscopy of Dental Tissues by Use of the Replica Method, D. Ahst. 2: 399-400. 19.57. 50. Thomas, B. 0. A. : L‘ Gerodontology, ’ ’ the Study of Changes in Oral Tissues Associated
With Aging, J. Am. Dent. A. 33: 207-213, 1946. J. C., and Costas, J. B.: Estudio de a Dentina dc compensacibn, Odont. Uruguaya, pp. 411-440, 1954. 22. Vorobiev, B., and Pi&t, E. K.: Osnovi anatomii, guistologii y embriologii subov y polosti rta, Berlin, 1922, Vrach. O., and Hess, W.: Lehrhuch der Konservierenden Zahnheilkunde, ed. 5, Lrip53. Walkhoff, zig, 1954, Johann Ambrosius Barth. 51. Turell,
Volume IL Number 8
CLASSIFICATION
OF DENTINE
54. Weider F. R.! &hour, I., and Mohamed, C. I.: Reparative Dentin Following Cavity Preparation and Fillings in the Rat Molars, ORAL BURG., ORAL MED. & ORAL PATH. 9: 221-232, 1956. 55. Willman, W.: Calcifications in the Pulp, Bur 34: 73-76, 1934. 56. Zander, H. A.: Physiology of the Dental Pulp, Queensland D. J., pp. 33-37, 1953-1954. 57. Zerosi, C.: Terapia Conservativa in Odonto-Stomatologia, Torino, 1955, Edizioni Minerva medica. HAMBURGO 250.