Veterinary Dentistry CTVT Chapter 34 pg 1297 1354

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Veterinary Dentistry CTVT Chapter 34, pg. 1297 -1354

Veterinary Dentistry CTVT Chapter 34, pg. 1297 -1354

Objectives �Recognize a patient’s dental health status �Perform techniques, as prescribed by a veterinarian,

Objectives �Recognize a patient’s dental health status �Perform techniques, as prescribed by a veterinarian, to promote and maintain dental health *Perform routine dental prophylaxis *Understand client education regarding home care

Dental Tasks for Veterinary Technicians �Oral examination and charting �Professional dental cleaning “Dental prophylaxis”

Dental Tasks for Veterinary Technicians �Oral examination and charting �Professional dental cleaning “Dental prophylaxis” �Taking and developing dental radiographs �Taking impressions and making models �Performing nonsurgical, subgingival root planning �Assisting with exodontics and endodontics �Client education *Procedures performed by veterinary technicians must not result in alterations in the shape, structure, or positional location of teeth in the dental arch.

Normal Dentition & Dental Anatomy

Normal Dentition & Dental Anatomy

Tooth Classification �Brachyodont teeth: small crown with long, well- developed roots; teeth do not

Tooth Classification �Brachyodont teeth: small crown with long, well- developed roots; teeth do not continue to grow or erupt throughout animal’s life. Ex: humans, carnivores, pigs �Diphyodonts have two sets of teeth: deciduous, then permanent. �Hypsodont teeth: long crown height and continue to erupt for most the animal’s lifetime. Ex: horses, rodents, and lagomorphs

Oral Anatomy �Upper teeth are embedded in the maxilla. �Lower teeth are embedded in

Oral Anatomy �Upper teeth are embedded in the maxilla. �Lower teeth are embedded in the mandible. �Rostral, upper and lower teeth are called incisors and are housed in the premaxilla, which is called incisive bone. � 2 nd most rostral teeth are the canine teeth, followed by the premolars and then lastly are molars (cheek teeth). �Palatine bone comprises most of the hard palate. Is this on the maxilla or mandible?

Dental Morphology �Incisors: in front of the mouth and are used for gnawing and

Dental Morphology �Incisors: in front of the mouth and are used for gnawing and grooming. �Canine Teeth: long and used for grasping and tearing • Premolars and Molars: are used for shearing and grinding.

Maxillary Arcade R

Maxillary Arcade R

Mandibular Arcade R

Mandibular Arcade R

Dentition �Mammals show great variety in dentition (numbers and types of teeth). �Dental formulas

Dentition �Mammals show great variety in dentition (numbers and types of teeth). �Dental formulas are used to classify the normal dentitions of different animal species.

Normal Dentition of Dogs and Cats �Puppies have 28 deciduous (primary / milk) teeth.

Normal Dentition of Dogs and Cats �Puppies have 28 deciduous (primary / milk) teeth. Eruption occurs between 3 to 6 weeks of age Canines and incisors first Premolars take 6 weeks; no molars �Dogs have 42 permanent teeth. Eruption occurs between 3 to 5 months �Kittens have 26 deciduous teeth. Eruption occurs at about 3 to 6 weeks �Cats have 30 permanent teeth. Eruption occurs about 3 to 6 months.

Normal Dentition of the Dog and Cat 42 30 upper I C P M

Normal Dentition of the Dog and Cat 42 30 upper I C P M lower I C P M

Tooth Morphology (Outer) � Crown = part of the tooth that is visible in

Tooth Morphology (Outer) � Crown = part of the tooth that is visible in the mouth above the gum line. � Shiny enamel covers the crown of the tooth. Hardest substance in the body. Prevents tooth from being invaded by bacteria and acids. If destroyed, will not re-grow. � The root is the tooth structure below the gum line and is covered by cementum. � The tip of the root is the apex of the tooth.

Tooth Morphology (Inner) �Dentin is the substance that composes the bulk of the tooth

Tooth Morphology (Inner) �Dentin is the substance that composes the bulk of the tooth Harder than bone but not as hard as enamel. Lies under the enamel and cementum. �Pulp cavity is located within the central core of the tooth and contains pulp. Pulp is composed of blood vessels, nerves, and connective tissue � Pulp produces dentin Pulp chamber is the portion of the pulp cavity located in the crown. Root canal is the portion located beneath the gum line.

Covers the crown Very hard bone that makes up the majority of tooth. Above

Covers the crown Very hard bone that makes up the majority of tooth. Above the gum line. Chamber Root canal Within the dentin, made up of nerves, blood vessels, and connective tissue Gingiva Covers the root Below the gum line. Shock absorbing lining; attaches tooth to the bony socket. Bony socket

Tooth Anatomy

Tooth Anatomy

Triadan System �Refers to teeth using a numeric system v 100 series: Right maxillary

Triadan System �Refers to teeth using a numeric system v 100 series: Right maxillary quadrant v 200 series: Left maxillary quadrant v 300 series: Left mandibular quadrant v 400 series: Right mandibular quadrant �Each tooth has its own predictable number Start with the most rostral tooth and move caudal If tooth is not present, skip that number

Triadan System- Canine M P

Triadan System- Canine M P

Triadan System-Feline Tip: Canines always end in 4; the first molar always ends in

Triadan System-Feline Tip: Canines always end in 4; the first molar always ends in 9

History and Extraoral Examination �Dental procedures require general anesthesia Obtain a proper history Ask

History and Extraoral Examination �Dental procedures require general anesthesia Obtain a proper history Ask about general medical info, medications, nutrition/treats, toys �Extraoral exam Palpate muscles of the face Retropulse the eyelids � Look for symmetric depth and firmness Look for ocular and nasal discharge Palpate submandibular lymph nodes

Intraoral Examination �The entire mouth should be evaluated: 1. Soft tissue Mucosa- should be

Intraoral Examination �The entire mouth should be evaluated: 1. Soft tissue Mucosa- should be pink or pigmented; no lesions seen � Two salivary ducts bumps dorsal to max. 4 th PM/1 st M Hard palate- covered in rugae � Incisive papilla- midline, caudal to incisors Pharynx- evaluate for inflammation/neoplasia Tongue- chewing lesions present? 2. Teeth Missing, fx, mobility, etc 3. Periodontium Inflammation, pockets, bone loss, etc *Radiographs often necessary

Normal vs. Abnormal

Normal vs. Abnormal

The Periodontum �The periodontium is the area where the tooth meets the gum. To

The Periodontum �The periodontium is the area where the tooth meets the gum. To attach the tooth to the jaw and provide support, resistant to normal, functional forces. It includes: � Gingiva � Periodontal ligament � Cementum � Alveolar bone

The Periodontum �Gingiva = gum tissue surrounding teeth �Gingival sulcus is the shallow groove

The Periodontum �Gingiva = gum tissue surrounding teeth �Gingival sulcus is the shallow groove between the tooth and the gingiva. Normal depth is 0 -3 mm in canines; up to 1 mm in felines Called a periodontal pocket when abnormal.

The Peridontium �Cementum is a bone-like tissue that covers the root surface. It is

The Peridontium �Cementum is a bone-like tissue that covers the root surface. It is stronger than bone but not as strong as enamel. It is capable of repairing itself. �Alveolar bone forms the tooth socket. Blood vessels and nerves run through the alveolar bone Periodontal ligament attaches cementum to the alveolar bone.

Dental Directional Terminology �Rostral refers to a structure that is closer to the front

Dental Directional Terminology �Rostral refers to a structure that is closer to the front of the head in comparison with another structure. �Caudal describes a structure toward the back of the head when compared to another structure. �Vestibular describes the tooth surface facing the lips. Buccal if mandibular; labial if maxillary �Facial describes vestibular surface of teeth visible from the front (only used for incisors). �Lingual refers to the surface of the mandibular teeth adjacent to the tongue. �Palatal refers to the surface of maxillary teeth adjacent to the palate.

Dental Terminology �Mesial refers to the portion of the tooth in line with the

Dental Terminology �Mesial refers to the portion of the tooth in line with the dental arcade that is closest to the most rostral portion of the midline of the dental arch. �Distal refers to the portion of the tooth that is closest to the most caudal portion of the midline of the dental arch. �Apical refers to a portion of the tooth closer to the apex, or tip of the root. �Coronal refers to a structure within a location closer to the crown of the tooth in relation to another structure. �Occlusal refers to the part of a tooth that meets with, or occludes with, the teeth of the opposite dental arcade. �Interdental space refers to the space between each individual tooth.

3. 1. 4. 5. 6. 2. 7. 8. 9.

3. 1. 4. 5. 6. 2. 7. 8. 9.

Occlusion � Orthodontics studies the way in which the teeth meet each other (occlude).

Occlusion � Orthodontics studies the way in which the teeth meet each other (occlude). � Occlusion is defined as the normal position of the teeth when the jaws are closed. In normal occlusion, teeth come together in a scissors bite. �The mandibular canine tooth resides in the interdental space of the upper third incisor and the upper canine tooth. �The upper fourth premolar tooth overlaps the lower first molar, which together, constitute the carnassial teeth. �Mandibular incisors:

Normal Scissors Occlusion: Lateral view of a dog skull. Premolars interdigitate toward the opposing

Normal Scissors Occlusion: Lateral view of a dog skull. Premolars interdigitate toward the opposing interdental space.

Malocclusion �Malocclusion is an abnormality in the position of the teeth. It can occur

Malocclusion �Malocclusion is an abnormality in the position of the teeth. It can occur in any of the three head shapes, but is more common in brachycephalic breeds. �It is more common in dogs but also occurs in cats. �There are four classes of malocclusions. (Class I, III, and IV) Class I- easily fixed with orthodontic correction OR not needed Class II-IV are skeletal malocclusions due to differing jaw length

Class I: Rostral Cross-bite �Maxillary incisors are caudal to the mandibular incisors. �Very common

Class I: Rostral Cross-bite �Maxillary incisors are caudal to the mandibular incisors. �Very common malocclusion in veterinary dentistry. �Thought to occur secondary to retained deciduous incisors. �Treatment consists of orthodontic movement or extraction of the abnormal teeth. Treat vs. not treat?

Rostral Cross-bite

Rostral Cross-bite

Class I: Caudal Cross-bite �Maxillary premolars/molars are positioned lingual to the mandibular opposing premolars/molars

Class I: Caudal Cross-bite �Maxillary premolars/molars are positioned lingual to the mandibular opposing premolars/molars �Occurs occasionally in dolichocephalic breeds. �More frequent professional prophylaxis will be needed for these pets.

Caudal Cross-bite �The maxillary fourth premolar is positioned abnormally inside of the lower first

Caudal Cross-bite �The maxillary fourth premolar is positioned abnormally inside of the lower first molar tooth. �This condition did not require treatment as the pet had a comfortable and functional occlusion (bite).

Class II: Mandibular Distoclusion �Mandibular brachygnathism: abnormally short mandible, normal maxilla �Referred to as

Class II: Mandibular Distoclusion �Mandibular brachygnathism: abnormally short mandible, normal maxilla �Referred to as “overshot” �Lack of self-cleaning ability and can create painful palate abrasions. �Not an accepted standard in any breed. Note: this may also be due to maxillary prognathism (not common)

Class III: Mandibular Mesiocclussion �Mandibular prognathism: abnormally long mandible, normal length maxilla �Referred to

Class III: Mandibular Mesiocclussion �Mandibular prognathism: abnormally long mandible, normal length maxilla �Referred to as “undershot” �These dogs will lose some of their self-cleaning ability and trap plaque and debris more easily. �Maxillary incisors can traumatize the mandible. �Accepted as normal in brachycephalic breeds such as Bulldogs, Pekingese, Boston terriers, Pugs, and Persian cats. Note: Could also be maxillary brachygnathism (not common)

Persistent Deciduous Teeth �Interfere with normal eruption pathway of permanent teeth malocclusion �Are a

Persistent Deciduous Teeth �Interfere with normal eruption pathway of permanent teeth malocclusion �Are a reservoir for debris dental disease �Early detection is key! �Common in small breed dogs �Extraction is almost always necessary Referred to as Interceptive Orthodontics *Note: deciduous teeth are numbered differently in the Triadan system (500, 600, 700, 800)

Persistent Deciduous Teeth �Most permanent teeth will erupt lingual or palatal to the deciduous

Persistent Deciduous Teeth �Most permanent teeth will erupt lingual or palatal to the deciduous teeth. (babies in front) �Exception: Permanent maxillary canine teeth will erupt rostral/mesial to the deciduous canine teeth. *Why is this significant?

Persistent Deciduous Canine Teeth Abnormal attrition

Persistent Deciduous Canine Teeth Abnormal attrition

Polydontia �Supernumerary teeth should not be confused with retained deciduous teeth. �Radiographs aid in

Polydontia �Supernumerary teeth should not be confused with retained deciduous teeth. �Radiographs aid in differentiation. How? �Occurs in about 10% of dogs and rarely in cats. �Unless extra tooth causes crowding, no treatment is necessary. Occasionally the extra teeth will erupt in an abnormal angle or be impacted. �If crowding increased chance of periodontal disease. (Extraction necessary)

Hypodontia �One or more teeth (usually incisors or premolars) do not form in the

Hypodontia �One or more teeth (usually incisors or premolars) do not form in the dental arcade. �Many breeds are affected. �Unerrupted or hypodontia? How do you confirm? �If permanent tooth is absent, a baby tooth will often remain in the arch for months to years. �No treatment; usually does not cause any problems.