Eruption of Permanent Premolars and Molars for Newfoundland Caribou

Abstract

The lower mandibles of 47 Newfoundland caribou ( Rangifer tarandus ) were examined to determine the approximate age when molar and permanent premolar teeth erupted. The approximate ages of eruption were: M1 3 months, M13 months, M3 25 months, and P23o-24 months. All the teeth were fully erupted by 271/e months of age. Table 1. The eruption of molars and permanent premolars of Newfoundland caribou. APPROXIMATE DATES SAMPLE AGE REMARKS RELATIVE TO AGE OF COLLECTED S£ZE ( MONTHS ) ERUPTION AND WEAR July 11-22 5 ll/2 Wear on all cusps DP2 and DP3, no wear DP4 August 24 1 3 M1-above gum line, milk premolars same as 2 months October 1 1 4 M1-anterior cusp worn, posterior cusp above gum November 5 1 S M1 anterior cusp worn, no wear posterior cusp November 11 2 51/2 Ml no change since 5 months December 2 1 6 M1 wear onboth cusps February 9-13 2 8 MM anterior cusp through bone in one jaw March 23 1 10 Mnot above bone June 5 1 12 Manterior cusp through gum September 16 1 l5l/2 Mwear on both cusps, M3 above bone October 16-18 3 161/o Manterior cusp above bone January 1-31 4 l9l/2 M.! anterior cusp above bone, posterior cusp through bone March 22 1 22 M3 both cusps above bone May 27-June 12 12 24 Varies from all DP's to all permanent premolars, M3 no wear anterior cusp) posterior cusp frequently not through bone June 22 1 25 Mno wear anterior cusp, posterior cusp beIow gum September 14-30 11 271/ All molars and premolars fully erupted 962 The purpose of this report is to provide information on the age of eruption of the lower molars and permanent premolars in Newfoundland caribou.