Читать книгу Blackwell's Five-Minute Veterinary Consult Clinical Companion - Группа авторов - Страница 25

 Utilizing the Triadan numbering system, the mouth is divided into quadrants.Remembering the mantras, “Do it right the first time” and “Always do your best/Be on top,” the top right quadrant is the 100s.As you look at the patient, the quadrants proceed clockwise (see Figure 3.29):Maxillary left quadrant is the 200s.Mandibular left quadrant is the 300s.Mandibular right quadrant is the 400s.

 Number from midline in each quadrant proceeding to the last molar:Incisors are _01 through _03.Figure 3.28 A summary of the simple steps to complete when interpreting radiographic film. The image shows dog mandibular incisors and canines, with missing lower right first incisor (401) and both first premolars (305, 405).Figure 3.29 Orient films with the crowns “in the mouth” like a Cheshire cat grin, with mandibular roots pointing down, maxillary roots pointing up. Triadan quadrant numbering begins in the top right and proceeds clockwise.Canines are always _04.Premolars are _05 through _08:The large upper carnassial tooth is the fourth premolar = 1/208.Cats do not have any _05s nor lower _06s.Molars are _09 up to _11 when present:The large lower carnassial tooth is the first molar = 3/409.Normally the last maxillary tooth in the dog is 1/210.Figure 3.30 Reading a radiograph. With premolars and molars, determine “where is the nose”; if the rostral aspect of the image is to the left, then the teeth are from a left quadrant. Images show left maxilla in a dog: note the white line formed by the dorsal plate of the alveolar process, present only in the maxilla.Figure 3.31 An extraoral film is read in the opposite way: right and left will be reversed compared to an intraoral film. Image shows left maxillary premolars in a cat (even though the nose is to the right).Normally the last mandibular tooth in the dog is 3/411.There is only M1 in each quadrant of the cat = _09.

 Deciduous teeth without permanent successors can be assessed as any other tooth periodontally and endodontically. They typically have finer/thinner crowns and roots and are designated by adding 400 to the normal permanent Triadan number.