Abstract
The surface of the maxillary and mandibular incisors of Spermophilus undulatus long-tailed ground squirrels, including those born in the current year and those that have hibernated (trapped one month or later after hibernation) is studied. The presence of daily growth increments on the incisors’ surface allows the evaluation of the eruption rate of the incisors; a specific change in the character of the growth increments corresponds to winter hibernation (hibernation zone), which serves as the time mark. Ratio between the eruption rates of the maxillary and mandibular incisors typical for rodents is found in young-of-the-year and some animals after hibernation. In these animals the eruption rate of the mandibular incisors is higher than the eruption rate of the maxillary incisors and can be taken as proportional to their length. In individuals that have hibernated and show proportional eruption of the incisors, the proportions of the total length of the incisor formed before hibernation zone are equal for the maxillary and mandibular incisors. In the individuals that also have hibernated and show the ratio between the total length of the maxillary and mandibular incisors typical for rodents, the eruption rate of the mandibular incisor is equal to or less than the eruption rate of the maxillary incisor and the proportion of the incisor formed before hibernation is greater in the mandibular incisor than in the maxillary. This disproportionate pattern of incisor eruption is not typical for rodents and is a result of inequal attrition of the maxillary and mandibular incisors, which ultimately results in the normal ratio of the total length of the maxillary and mandibular incisors.
Similar content being viewed by others
References
Badmaev, B.B., Dlinnokhvostyi suslik v usloviyakh Zapadnogo Zabaikal’ya (Long-Tailed Ground Squirred in Western Transbaikalia), Novosibirsk: Nauka, 2007.
Berkovitz, B.K.B. and Faulkes, C.G., Eruption Rates of the Mandibular Incisors of Naked Mole-Rats (Heterocephalus glaber), J. Zool. (London), 2001, vol. 255, pp. 461–466.
Berkovitz, B.K.B. and Thomas, N.R., Unimpeded Eruption in the Root-Resected Lower Incisor of the Rat with a Preliminary Note on Root Transection, Arch. Oral. Biol., 1969, vol. 14, p. 771.
Burn-Murdoch, R.A., The Effect of the Consistency of the Diet on Eruption Rates and Lengths of Incisor Teeth in Rats, Arch. Oral. Biol., 1993, vol. 38, pp. 699–706.
Burn-Murdoch, R.A., The Length and Eruption Rates of Incisor Teeth in Rats After One or More of Them Had Been Unimpeded, Eur. J. Orthodontics, 1999, vol. 21, pp. 49–56.
Goodwin, H.T. and Ryckman, E.M., Lower Incisors of Prairie Dogs (Cynomys) as Biorecorders of Hibernation and Season of Death, J. Mammal., 2006, vol. 87, pp. 1002–1012.
Goodwin, H.T., Michener, G.R., Gonzalez, D., et al., Hibernation is Recorded in Lower Incisors of Recent and Fossil Ground Squirrels (Spermophilus), J. Mammal., 2005, vol. 86, p. 323.
Klevezal’, G.A. and Lobkov, V.A., Daily Increments and the Hybernation Zone on the incisor Surface of Ground Squirrels of the Genus Spermophilus, Zool. Zh., 2008, vol. 87, no. 12, pp. 1495–1503.
Klevezal’, G.A., Incisor Growth Dynamics and Daily Increments on Their Surface in Three Species of Small Rodents, Zool. Zh., 2010, vol. 89, no. 3, pp. 360–370.
Klevezal’, G.A., Pucek, M., and Sukhovskaja, L.I., Incisor Growth in Voles, Acta Theriol., 1990, vol. 35, pp. 331–344.
Law, K.T., Lee, C.K., King, N.M., et al., The Relationship between Eruption and Length of Mandibular Incisors in Young Rats, Med. Sci. Monit., 2003, vol. 9, pp. 47–53.
Michaeli, Y. and Weinreb, M.M., Role of Attrition in the Physiology of the Rat Incisor. III. Prevention of Attrition and Occlusal Contact in the Non Articulating Incisor, J. Dent. Res., 1968, vol. 47, pp. 633–640.
Michaeli, Y., Weinreb, M.M., and Zajicek, G., Role of Attrition and Occlusal Contact in the Physiology of the Rat Incisor. VIII. Tooth Length and Occlusal Plane as Regulating Factors of Eruption and Attrition Rates, J. Dent. Res., 1974, vol. 53, pp. 1215–1218.
Miller, R.S., Rate of Incisor Growth in the Mountain Pocket Gopher, J. Mammal., 1958, vol. 39, pp. 380–385.
Ness, A.R., Movement and Forces in Tooth Eruption, Adv. Oral. Biol., 1964, vol. 1, pp. 33–75.
Radtke, G. and Pilz, M.E., Untersuchungen zum Nagezanwachstum von Laboratoriumssaugern, Stomatol. DDR, 1982, vol. 32, pp. 206–211.
Rinaldi, C., A New Technique for Assessing the Incremental Growth of Rodent Incisors, in Proc. 10th International Symposium on Dental Morphology, Berlin: “M” Marketing-Services, 1995, pp. 190–194.
Rinaldi, C., A Record of Hibernation in the Incisor Teeth of Recent and Fossil Marmots (Marmota flaviventris), Proc. 11th International Symposium on Dental Morphology, Oulu, Finland: Oulu Univ. Press, 1999, pp. 112–119.
Sarnat, B.G. and Hook, W.E., Effect of Hibernation on Tooth Development, Anat. Rec., 1942, vol. 83, pp. 471–491.
Shadle, A.R., Bolton, W., Garona, B., et al., The Extrusive Growth and Attrition of the Incisors in Cynomys L. ludovicianus (Ord), Anat. Rec., 1945, vol. 93, pp. 349–353.
Shadle, A.R., Ploss, W.R., and Marks, E.M., The Extrusive Growth and Attrition of the Incisor Teeth of Erethison dorsatum, Anat. Rec., 1944, vol. 90, pp. 337–341.
Shadle, A.R., Valvo, N.I., and Eckhert, K.M., The Extrusive Growth and Attrition of the Incisor Teeth of Cavia cobaya, Anat. Rec., 1938, vol. 71, pp. 497–502.
Shadle, A.R., Wagner, L.G., and Jacobs, T., The Extrusive Growth and Attrition of the Incisors in Albino and Hybrid Rattus norvegicus (Erxeben), Anat. Rec., 1936, vol. 64, pp. 321–325.
Smith, C.E. and Warshawsky, H., Movement of Entire Cell Population during Renewal of the Rat Incisor as Shown by Radiography after Labeling with 3H-Thymidine. The Concept of a Continuously Differentiating Cross-Sectional Segment, Am. J. Anat., 1976, vol. 145, pp. 225–260.
Smith, C.E. and Warshawsky, H., Radiographic Determination of the Length of Maxillary and Mandibular Incisors in Rats, J. Dent. Res., 1973, vol. 52, pp. 1234–1237.
Sokal, R.R. and Rohlf, F.J., Biometry, San Francisco: Freeman, 1981.
Taylor, A.C. and Butcher, E.O., The Regulation of Eruption Rate in the Incisor Teeth of the White Rat, J. Exp. Zool., 1951, vol. 117, pp. 165–188.
Wang, X.-P., Suomalainen, M., and Thesleff, I., Regulation of the Continuous Growth of the Mouse Incisor by Epithelial-Mesenchymal Interactions, Eur. Cells Mater., 2007, vol. 14, no. Suppl. 2, p. 21.
Weinreb, M.M., Assif, D., and Michaeli, Y., Role of Attrition in the Physiology of the Rat Incisor. I. The Relative Value of Different Components of Attrition and Their Effect on Eruption, J. Dent. Res., 1967, vol. 46, pp. 527–531.
Wise, G.E., Frazier-Bowers, S., and D’souza, R.N., Cellular, Molecular, and Genetic Determinants of Tooth Eruption, Crit. Rev. Oral. Biol. Med., 2002, vol. 13, pp. 323–335.
Zuri, I., Kaffe, I., Dayan, D., et al., Incisor Adaptation to Fossorial Life in the Blind Mole Rat, Spalax ehrenbergi, J. Mammal., 1999, vol. 80, pp. 734–741.
Author information
Authors and Affiliations
Corresponding author
Additional information
Original Russian Text © G.A. Klevezal’, E.G. Potapova, 2010, published in Ontogenez, 2010, Vol. 41, No. 3, pp. 204–212.
Rights and permissions
About this article
Cite this article
Klevezal’, G.A., Potapova, E.G. Disproportionate eruption of maxillary and mandibular incisors in the long-tailed ground squirrel. Russ J Dev Biol 41, 168–175 (2010). https://doi.org/10.1134/S1062360410030057
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1134/S1062360410030057