Fig. 2.1 Diagram of a young tooth. The pulp of the crown and root occupies a great deal of space, while the tooth walls are still very thin. The Hertwig epithelial root sheath is soft and the apical foramen provides a wide point of entry to the dental pulp.

Fig. 2.2 Diagram of a mature tooth. The “adult” tooth has a closed pulp chamber that narrows and shrinks inward as the animal ages, forming normal dentin.

Fig. 2.3 Junctional gingival epithelium. In a medium-sized dog, the normal gingival sulcus is approximately 2 mm deep and in cats, it is approximately 1 mm deep. Near the sulcus floor, special non-keratinized cells attach the gingiva to the tooth at the cementoenamel junction.

Fig. 2.4 Cells of the junctional gingival epithelium. The cells of the junctional gingival epithelium employ hemidesmosomes for attachment to the tooth surface. The epithelial cells are connected via desmosomes. Because they are non-keratinized, these cell layers are permeable and permit the host’s immune factors and cells to penetrate the gingiva at the sulcus.

Fig. 2.5 Comparison of healthy and diseased periodontium. The periodontium on the left is healthy. The inner lining of the gingival sulcus, along with the junctional gingival epithelium, seals off the periodontium on the oral cavity side, forming a gingival cuff. The periodontium on the right is diseased. The junctional gingival epithelium (orange) has migrated apically. Normal gingival mucosal cells have shifted into the sulcus, but are unable to provide a barrier. The gingival sulcus has deepened due to the damaged epithelium and desmodontal attachment and the loss of the fibrous and bony support of the alveolar bone.

Fig. 2.6 Maxilla. The incisors are located in the premaxillary bone, and the canine teeth and cheek teeth are embedded in the maxillary bone. The palatine bone does not contain any teeth. The two large rostral openings between the maxillary and premaxillary bones are the palatine fissures, through which the vomeronasal organ communicates with the oral cavity.

Fig. 2.7 Mandible. The mandible consists of the horizontal body of the mandible and the vertical ramus of mandible. While the maxilla increases in size appositionally and along the sutures, the mandible widens caudally. Each mandibular condyle articulates with the base of the skull at the mandibular fossa of the temporal bone.

Fig. 2.8 Tooth classification. The different groups of teeth are color-coded as follows: incisors: blue; canine teeth: green; premolars: orange; molars: yellow.

Fig. 2.9 Lateral view of the salivary glands. The parotid gland (green) is situated directly below the base of the ear with one rostral and one caudal part. Directly below the parotid glands, in the area of Viborg’s triangle, is the mandibular gland (red), which is covered by a capsule that includes the caudal part of the sublingual gland (blue). The zygomatic gland (magenta), is located separately, behind the zygomatic arch.

Fig. 2.10 Ventral view of the salivary glands. The ducts of the mandibular and sublingual glands open at the frenulum of the tongue. The duct of the parotid gland opens on the buccal mucosa at the level of the buccal surface of the maxillary carnassial teeth. The short duct of the zygomatic gland opens just caudally to this.

Fig. 2.11 Canine dental chart, dentition. Dogs have a total of 42 permanent teeth. The only teeth with cusps for grinding are the molars. The chart has a separate box for each tooth.

Fig. 2.12 Feline dental chart, dentition. Cats have 30 teeth, all of which have only a cutting function.

Fig. 2.13 Canine dental chart, detail. The boxes containing an “x” are used to record the individual pocket depths of each area. The veterinarian can also record planned and past treatments here.

Fig. 2.14 Canine skull, frontal view. The frontal view of the canine skull shows the close anatomical proximity of the maxillary canine roots to the nasal cavity. The mesial surface of the maxillary canine root is separated from the nasal cavity by only a paper-thin bony cover.

Fig. 2.15 Canine maxilla, lateral view. The lateral view shows the proximity of the caudal maxillary cheek teeth and the orbital cavity. The orbital floor is not protected by a bony structure, but consists of soft tissue. Firmness of the orbital floor thus may indicate inflammatory changes in the caudal maxilla or in the space caudal to the molars....