Equinos

• Caudal hooks


  Dominant lower or upper last molar overhanging opposing molar
• Rostral hooks


  Dominant upper front premolars overhang lower premolars
• Ramps


  Excessive height to lower premolars
• Enamel points


  Sharp points that generally form on the outside of the upper molars and the inside of the lower molars
• Sheared molar table


  Extreme angulation of chewing surface of molars
• Wave complexes


  Molar arcade develops an uneven "wavelike" appearance generally involving many premolars and molars
• Stepped molars


  Molar arcade develops stepped-like appearance
• Accentuated transverse ridges


  Enlarged ridges that run across chewing surfaces of molars
• Periodontal pockets


  Gum disease around tooth causing an area for feed to pocket
• Diastema


  Space that occurs between two adjoining teeth
• Overbite


  Upper incisors protrude in front of lower incisors
• Underbite


  Lower incisors protrude in the front of upper incisors
• Ventral curvature (Smile)


  Outer corner lower incisors grow longer relative to outer corner upper incisors
• Dorsal curvature (Frown)


  Outer corner upper incisors grow longer relative to outer corner lower incisors
• Offset or diagonal bite

  Upper incisors on one side of mouth are excessively long and lower incisors on opposite side are excessively long, causing incisors to meet on a diagonal
• Bone spur


  Mandibular periotitis or abnormal bony growth due to trauma
• Wolf tooth


  Small shallow rooted teeth in front of premolars. Most common in upper jaw. Can occasionally occur in front of lower premolars

  
• Blind wolf tooth


  Abnormal wolf tooth that does not break through gums

  
• Being able to pinpoint age within a fairly narrow range can be of use to owners of unregistered horses or horses whose age is unknown for any reason
• Many health and nutrition management decisions are directly related to age and dental wear, making it even more important for all horse owners to have a general understanding of how a horse's mouth changes with age
• Up until recently when organized associations started keeping birth dates on registered horses, most horse professionals took great pride in their ability to determine age by examining the teeth of any horse
• Aging the horse by its teeth is not an exact science, but changes do occur that can help determine approximate age, and anyone can learn the basics
• Deciduous

  Temporary milk teeth
• Foals' milk teeth eruption


  1. Central incisors erupt within 8 days

  2. Intermediate incisors erupt by 8 weeks

  3. Corner incisors erupt by 8 months
• Deciduous teeth can be distinguished from permanent teeth because they are wider than they are tall and they have shallow roots
• Twelve premolars will also erupt within 2 weeks of age, three on each side of the top and bottom jaws
• Premolars are typically not used in aging horses as they are more difficult to view
• Pattern of deciduous tooth shedding

  1. Central incisors shed at 2 1/2 years

  2. Intermediate incisors shed at 3 1/2 years

  3. Corner incisors shed at 4 1/2 years

  
• Average ages of tooth eruption in horses

  • Deciduous 1st incisor (or centrals) - birth or first week
  • Deciduous 2nd incisor (or intermediate) - 4 to 6 weeks
  • Deciduous 3rd incisor (or corners) - 6 to 9 months
  • Deciduous 1st, 2nd, 3rd premolar - birth or first 2 weeks
  • Permanent 1st incisor (or centrals) - 2 1/2 years
  • Permanent 2nd incisor (or intermediate) - 3 1/2 years
  • Permanent 3rd incisor (or corners) - 4 1/2 years
  • Permanent canine (or bridle) - 4-5 years
  • Permanent 1st premolar (or wolf tooth) - 5-6 months
  • Permanent 2nd premolar - 2 1/2 years
  • Permanent 3rd premolar - 3 years
  • Permanent 4th premolar - 4 years
  • Permanent 1st molar - 9-12 months
  • Permanent 2nd molar - 2 years
  • Permanent 3rd molar - 3 1/2-4 years

  
• Canine teeth (tushes)


  Located between the corner incisor and the molars, appear during the horse's 4-year-old year
• Wolf teeth


  Very shallowly rooted teeth found adjacent to the first premolar, commonly extracted as they may interfere with the bit
• Horses are considered to have a "full mouth" at 5 years old, which means that all permanent teeth have erupted and are in wear
• Grinding surfaces of incisors


  • Cup disappears from bottom central incisors at 6 years, intermediates at 7 years, corners at 8 years
  • Dental star appears in central incisors at 8 years, intermediates at 9 years, corners at 10 years
  • Grinding surface shape changes from rectangular under 9 years, to rounded 9-mid teens, to triangular later teens and older
  • Tooth visible below gum line decreases with age, "long in the tooth" for older horses
  • Tooth angle changes from more vertical in young horses to more angled in older horses
• Galvayne's groove


  Groove that appears near the gum line of the corner incisor, indicates age over 10 years
• 1. and 11-year hook


  Hook that forms on the top corner incisor due to lack of opposing surface, appears at 7 years and reappears at 11 years
• These guidelines for aging by dental wear can vary depending on what the horse is eating and on vices, like cribbing
• While all horses do not follow the rules, these guidelines can be useful tools in evaluating a horse's age
• Large animals


  • Most are herbivores
  • Efficient dental function is key to food intake and normal body condition
• Dental formula and eruption schedule


  • Deciduous and permanent teeth
  • Variations in anatomic structure, dental formula, and eruption schedule for different species
• Ruminants


  Lack upper incisor teeth, with the mandibular brachydont (short-crowned) incisors meeting with a maxillary cornified dental pad