Calcified Tissue International

, Volume 78, Issue 5, pp 278–284 | Cite as

Ameloblastin Fusion Protein Enhances Pulpal Healing and Dentin Formation in Porcine Teeth

  • Y. Nakamura
  • I. Slaby
  • A. Spahr
  • G. Pezeshki
  • K. Matsumoto
  • S. P. Lyngstadaas
Laboratory Investigations


Ameloblastin (Ambn, also named “amelin” or “sheathlin”) is a protein participating in enamel formation and mesenchymal-ectodermal interaction during early dentin formation in developing teeth. Experiments have demonstrated an association between Ambn expression and healing of acute pulp wounds. The purpose of this study was to investigate if local application of recombinant fusion Ambn (rAmbn) could influence reparative dentin formation in pulpotomized teeth. In this randomized, double-blinded study, pulpotomy was performed in 28 lower central incisors in 17 adult miniature pigs. Following the surgical procedure, the exposed pulp tissue was covered either with rAmbn or with calcium hydroxide. After 2, 4, or 8 weeks, the teeth were extracted and examined by histomorphometry and immunohistochemistry using antibodies against porcine ameloblastin, collagen type I, and dentin sialoprotein (DSP). In rAmbn-treated teeth, a substantial amount of newly formed reparative dentin was observed at the application site, completely bridging the pulpal wound. Dentin formation was also observed in calcium hydroxide-treated teeth; however, the amount of reparative dentin was significantly smaller (P < 0.001) than after rAmbn treatment. Immunohistochemistry confirmed that the new hard tissue formed was similar to dentin. This is the first time a direct link between ameloblastin and dentin formation has been made in vivo. The results suggest potential for rAmbn as a biologically active pulp-dressing agent for enhanced pulpal wound healing and reparative dentin formation after pulpotomy procedures.


Ameloblastin Amelin Dental pulp healing Dentinogenesis Pulpotomy 



The DSP antibody was a kind gift from Dr. H. H. Ritchie. We also thank E. Lundberg, H. Ekdahl, and U.-B. Carlsson for excellent assistance during the animal procedures and B. Fabi for kind help with photographs and figures. The work was sponsored by EU grant QLK3-CT-2001-00090 MATRIX and Japan Society for Promotion of Science (JSPS) grant in scientific research (C) 16591921.


  1. 1.
    Yamamura T (1985) Differentiation of pulpal cells and inductive influences of various matrices with reference to pulpal wound healing. J Dent Res 64:530–540PubMedGoogle Scholar
  2. 2.
    Ranly DM (1994) Pulpotomy therapy in primary teeth: new modalities for old rationales. Pediatr Dent 16:403–409PubMedGoogle Scholar
  3. 3.
    Ranly DM, Garcia-Godoy F (2000) Current and potential pulp therapies for primary and young permanent teeth. J Dent 28:153–161CrossRefPubMedGoogle Scholar
  4. 4.
    Tziafas D, Smith AJ, Lesot H (2000) Designing new treatment strategies in vital pulp therapy. J Dent 28:77–92CrossRefPubMedGoogle Scholar
  5. 5.
    Nakashima M (1994) Induction of dentin formation on canine amputated pulp by recombinant human bone morphogenetic proteins (BMP)-2 and -4. J Dent Res 73:1515–1522PubMedGoogle Scholar
  6. 6.
    Rutherford RB, Wahle J, Tucker M, Rueger D, Charette M (1993) Induction of reparative dentin formation in monkeys by recombinant human osteogenic protein-1. Arch Oral Biol 38:571–576CrossRefPubMedGoogle Scholar
  7. 7.
    Nakashima M (1989) Dentin induction by implants of autolyzed antigen-extracted allogeneic dentin on amputated pulps of dogs. Endod Dent Traumatol 5:279–286CrossRefPubMedGoogle Scholar
  8. 8.
    Termine JD, Belcourt AB, Christner PJ, Conn KM, Nylen MU (1980) Properties of dissociatively extracted fetal tooth matrix proteins. I. Principal molecular species in developing bovine enamel. J Biol Chem 255:9760–9768PubMedGoogle Scholar
  9. 9.
    Nakamura Y, Hammarström L, Lundberg E, Ekdahl h, matsumoto k, Gestrelius S, Lyngstadaas SP (2001) Enamel matrix derivative promotes reparative processes in the dental pulp. Adv Dent Res 15:105–107PubMedGoogle Scholar
  10. 10.
    Nakamura Y, Hammarström L, matsumoto k, Lyngstadaas SP (2002) The induction of reparative dentin by enamel proteins. Int Endod J 35:407–417CrossRefPubMedGoogle Scholar
  11. 11.
    Nakamura Y, Slaby I, Matsumoto K, Richie HH, Lyngstadaas SP (2004) Immunohistochemical characterization of rapid dentin formation induced by enamel matrix derivative. Calcif Tissue Int 75:243–252CrossRefPubMedGoogle Scholar
  12. 12.
    Cerny R, Slaby I, Hammarström L, Wurtz T (1996) A novel gene expressed in rat ameloblasts codes for proteins with cell binding domains. J Bone Miner Res 11:883–891PubMedGoogle Scholar
  13. 13.
    Krebsbach PH, Lee SK, Matsuki Y, Kozak CA, Yamada KM, Yamada Y (1996) Full-length sequence, localization, and chromosomal mapping of ameloblastin. A novel tooth-specific gene. J Biol Chem 271:4431–4435CrossRefPubMedGoogle Scholar
  14. 14.
    Hu CC, Fukae M, Uchida T, Qian Q, Zhang CH, Ryu OH, Tanabe T, Yamakoshi Y, Murakami C, Dohi N, Shimizu M, Simmer JP (1997) Sheathlin: cloning, cDNA/polypeptide sequences, and immunolocalization of porcine enamel sheath proteins. J Dent Res 76:648–657PubMedCrossRefGoogle Scholar
  15. 15.
    MacDougall M, Simmons D, Gu TT, Forsman-Semb K, Mardh CK, Mesbah M, Forest N, Krebsbach PH, Yamada Y, Berdal A (2000) Cloning, characterization and immunolocalization of human ameloblastin. Eur J Oral Sci 108:303–310CrossRefPubMedGoogle Scholar
  16. 16.
    Uchida T, Murakami C, Wakida K, Dohi N, Iwai Y, Simmer JP, Fukae M, Satoda T, Takahashi O (1998) Sheath proteins: synthesis, secretion, degradation and fate in forming enamel. Eur J Oral Sci 106(suppl 1):308–314PubMedGoogle Scholar
  17. 17.
    Fong CD, Slaby I, Hammarström L (1996) Amelin: an enamel-related protein, transcribed in the cells of epithelial root sheath. J Bone Miner Res 11:892–898PubMedCrossRefGoogle Scholar
  18. 18.
    Fong CD, Cerny R, Hammarstöm L, Slaby I (1998) Sequential expression of amelin gene in mesenchymal and epithelial cells during odontogenesis in rats. Eur J Oral Sci 106(Suppl 1):324–330PubMedGoogle Scholar
  19. 19.
    Spahr A, Lyngstadaas SP, Slaby I, Haller B, Boeckh C, Tsoulfidou F, Hammarstrom L (2002) Expression of amelin and trauma-induced dentin formation. Clin Oral Investig 6:51–57PubMedGoogle Scholar
  20. 20.
    Ritchie H, Wang L-H (1998) The expression of DSP protein from a baculovirus construct containing rat DSP-PP cDNA. J Dent Res 77:157Google Scholar
  21. 21.
    Van Ittersum J, Ritchie H (2002) Post-translational analysis of rat dentin phosphophoryn from dentin matrix and a DSP-PP construct. J Dent Res 81:A278Google Scholar
  22. 22.
    Hsu SM, Raine L, Fanger H (1981) Use of avidin-biotin-peroxidase complex (ABC) in immunoperoxidase techniques: a comparison between ABC and unlabeled antibody (PAP) procedures. J Histochem Cytochem 29:577–580PubMedGoogle Scholar
  23. 23.
    Butler WT (1995) Dentin matrix proteins and dentinogenesis. Connect Tissue Res 33:59–65PubMedGoogle Scholar

Copyright information

© Springer Science+Business Media, Inc. 2006

Authors and Affiliations

  • Y. Nakamura
    • 1
  • I. Slaby
    • 2
  • A. Spahr
    • 3
  • G. Pezeshki
    • 3
  • K. Matsumoto
    • 1
  • S. P. Lyngstadaas
    • 4
  1. 1.Department of Clinical Cariology and EndodontologySchool of Dentistry, Showa UniversityOhta-kuJapan
  2. 2.Biora AB, a company of Straumann AGMalmöSweden
  3. 3.Department of Conservative Dentistry and PeriodontologyUniversity of UlmUlmGermany
  4. 4.Department of Biomaterials, Faculty of DentistryUniversity of OsloOsloNorway

Personalised recommendations