Dental disorders and their management

Lisa Milella

doi:10.22233/9781910443149.7

British Small Animal Veterinary Association , 324 (2013); https://doi.org/10.22233/9781910443149.7

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Dental disorders and their management

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Author: Lisa Milella
From: BSAVA Manual of Feline Practice
Item: Chapter 7, pp 324 - 334
DOI: 10.22233/9781910443149.7
Copyright: © 2013 British Small Animal Veterinary Association
Publication Date: January 2013

Abstract

This chapter will look at the diagnosis and management of the most important dental disorders that are encountered in feline practice: tooth resorption (feline odontoclastic resorptive lesions) and chronic gingivostomatitis. Quick reference guides: Dental examination; Tooth extraction.

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Figures

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7.1

Signs consistent with FORLs. (a) Hyperplastic gingival tissue growing over a resorptive defect in the mandibular 3rd premolar (PM) of a 7-year-old DSH cat. (b) Pink area on the crown of a mandibular canine tooth. (c) The buccal and lingual aspects of both mandibular canine teeth are affected. The visible demarcation between the enamel and the granulation tissue is scalloped, giving the impression that the tissue is growing into the crown. The gingival margin is inflamed. (d) A red spot of inflamed gingival tissue on the crown of the mandibular 3rd PM covering a FORL. (e) The distal part of the crown of the mandibular molar is missing as a result of a FORL. The mandibular 4th PM also has a FORL at the furcation: the gingiva is inflamed and the crown has a scalloped appearance at the margin of tissue and tooth. © 2013 British Small Animal Veterinary Association

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7.1 Signs consistent with FORLs. (a) Hyperplastic gingival tissue growing over a resorptive defect in the mandibular 3rd premolar (PM) of a 7-year-old DSH cat. (b) Pink area on the crown of a mandibular canine tooth. (c) The buccal and lingual aspects of both mandibular canine teeth are affected. The visible demarcation between the enamel and the granulation tissue is scalloped, giving the impression that the tissue is growing into the crown. The gingival margin is inflamed. (d) A red spot of inflamed gingival tissue on the crown of the mandibular 3rd PM covering a FORL. (e) The distal part of the crown of the mandibular molar is missing as a result of a FORL. The mandibular 4th PM also has a FORL at the furcation: the gingiva is inflamed and the crown has a scalloped appearance at the margin of tissue and tooth.

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7.2

(a) Maxillary 3rd PM and 4th PM with gingivitis, plaque and calculus. (b) The same teeth following plaque and calculus removal. A FORL is visible at the furcation of the 3rd PM and on its distal root and crown. Gingival recession can also be seen on the right maxillary 4th PM. © 2013 British Small Animal Veterinary Association

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7.2 (a) Maxillary 3rd PM and 4th PM with gingivitis, plaque and calculus. (b) The same teeth following plaque and calculus removal. A FORL is visible at the furcation of the 3rd PM and on its distal root and crown. Gingival recession can also be seen on the right maxillary 4th PM.

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7.3

(a) Type 1 FORL affecting the left mandibular canine, seen as a radiolucency at the alveolar margin (the edge of the portion of bone that contains the tooth). The root and the periodontal ligament can still be distinguished from the surrounding bone. (b) Type 2 FORLs affecting both mandibular canine teeth. There are radiolucent areas in the crown as well as loss of the structure of the root and periodontal ligament. (c) Normal radiograph for comparison. (See box above for explanation of arrows.) © 2013 British Small Animal Veterinary Association

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7.3 (a) Type 1 FORL affecting the left mandibular canine, seen as a radiolucency at the alveolar margin (the edge of the portion of bone that contains the tooth). The root and the periodontal ligament can still be distinguished from the surrounding bone. (b) Type 2 FORLs affecting both mandibular canine teeth. There are radiolucent areas in the crown as well as loss of the structure of the root and periodontal ligament. (c) Normal radiograph for comparison. (See box above for explanation of arrows.)

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7.4

(a) The left mandibular 4th PM and molar have type 1 FORLs, seen as a radiolucent area at the furcation of the tooth. The roots of the 4th PM remain relatively unaffected, whilst the lesion has resorbed most of the coronal part of the distal root of the molar, with the apical two-thirds remaining unaffected. (b) The left mandibular 4th PM and molar on this radiograph are affected by type 2 FORLs. The left mandibular 3rd PM is missing clinically but ghost roots are visible radiographically. Although the outline of both roots of the 4th PM can be seen, only its most mesial root is visible. There is no periodontal ligament space around the roots, the lamina dura has been lost and the density of the dentine resembles bone. (c) Normal radiograph for comparison. (See box above for explanation of arrows.) © 2013 British Small Animal Veterinary Association

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7.4 (a) The left mandibular 4th PM and molar have type 1 FORLs, seen as a radiolucent area at the furcation of the tooth. The roots of the 4th PM remain relatively unaffected, whilst the lesion has resorbed most of the coronal part of the distal root of the molar, with the apical two-thirds remaining unaffected. (b) The left mandibular 4th PM and molar on this radiograph are affected by type 2 FORLs. The left mandibular 3rd PM is missing clinically but ghost roots are visible radiographically. Although the outline of both roots of the 4th PM can be seen, only its most mesial root is visible. There is no periodontal ligament space around the roots, the lamina dura has been lost and the density of the dentine resembles bone. (c) Normal radiograph for comparison. (See box above for explanation of arrows.)

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7.5

(a) Type 1 FORL affecting the left maxillary 3rd PM seen as a radiolucent defect in the crown. (b) Type 2 FORL affecting the left maxillary 3rd PM and 4th PM. The roots of the 3rd PM appear less dense and have lost the periodontal ligament and lamina dura. The mesiopalatal root of the 4th PM is most affected, with the mesiobuccal and distal roots retaining their periodontal ligament and the surrounding lamina dura. (c) Normal radiograph for comparison. (See box above for explanation of arrows.) © 2013 British Small Animal Veterinary Association

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7.5 (a) Type 1 FORL affecting the left maxillary 3rd PM seen as a radiolucent defect in the crown. (b) Type 2 FORL affecting the left maxillary 3rd PM and 4th PM. The roots of the 3rd PM appear less dense and have lost the periodontal ligament and lamina dura. The mesiopalatal root of the 4th PM is most affected, with the mesiobuccal and distal roots retaining their periodontal ligament and the surrounding lamina dura. (c) Normal radiograph for comparison. (See box above for explanation of arrows.)

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7.6

Feline chronic gingivostomatitis. (a) The canines and incisors of a 2-year-old male neutered DSH cat. The inflammation had been persistent despite medical treatment for the past 9 months. The inflammation present extends the whole width of the attached gingiva to the level of the mucogingival junction. (b) The same cat, showing severe gingivitis and inflammation of the premolars and molars extending beyond the mucogingival junction. The inflammation can be seen in the oral mucosa on the left side (top of photo) and also extends on to the palatal mucosa on the right side of the mouth (base of photo). The gingival tissue is also hyperplastic. © 2013 British Small Animal Veterinary Association

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7.6 Feline chronic gingivostomatitis. (a) The canines and incisors of a 2-year-old male neutered DSH cat. The inflammation had been persistent despite medical treatment for the past 9 months. The inflammation present extends the whole width of the attached gingiva to the level of the mucogingival junction. (b) The same cat, showing severe gingivitis and inflammation of the premolars and molars extending beyond the mucogingival junction. The inflammation can be seen in the oral mucosa on the left side (top of photo) and also extends on to the palatal mucosa on the right side of the mouth (base of photo). The gingival tissue is also hyperplastic.

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7.7

Severe proliferative stomatitis extending into the fauces. This cat had persistent inflammation for 4 years (despite treatment) prior to presentation. © 2013 British Small Animal Veterinary Association

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7.7 Severe proliferative stomatitis extending into the fauces. This cat had persistent inflammation for 4 years (despite treatment) prior to presentation.

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7.8

Inflammation is more severe caudally at the level of the left maxillary 4th PM and left mandibular molar, extending almost to the mucocutaneous junction at the commissure. Bleeding of the gingiva of the left mandibular molar is just visible in the bottom corner of the photo. Inflammation of the oral mucosa can be seen above the maxillary canine tooth (which is fractured) and the maxillary 2nd, 3rd and 4th PMs. © 2013 British Small Animal Veterinary Association

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7.8 Inflammation is more severe caudally at the level of the left maxillary 4th PM and left mandibular molar, extending almost to the mucocutaneous junction at the commissure. Bleeding of the gingiva of the left mandibular molar is just visible in the bottom corner of the photo. Inflammation of the oral mucosa can be seen above the maxillary canine tooth (which is fractured) and the maxillary 2nd, 3rd and 4th PMs.

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7.9

Intraoral radiography of the cat in Figure 7.7 . (a) Intraoral radiograph of the left mandible, showing root remnants from all previously ‘extracted’ teeth. (b) Intraoral radiograph of the right mandible, showing six root remnants. The root remnants have intact periodontal ligaments and show no signs of resorption. The root fragments also extend above the alveolar bone margin. This is the reason for the poor response to previous treatment; the root remnants remain a focus of infection, pain and inflammation. © 2013 British Small Animal Veterinary Association

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7.9 Intraoral radiography of the cat in Figure 7.7 . (a) Intraoral radiograph of the left mandible, showing root remnants from all previously ‘extracted’ teeth. (b) Intraoral radiograph of the right mandible, showing six root remnants. The root remnants have intact periodontal ligaments and show no signs of resorption. The root fragments also extend above the alveolar bone margin. This is the reason for the poor response to previous treatment; the root remnants remain a focus of infection, pain and inflammation.

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7.11

(a) This 6-year-old DSH cat had been treated for chronic gingivostomatitis 3 months previously by extraction of the PMs and molars, as well as the left maxillary canine. There is mild inflammation caudally, although all the extraction sites appear to have healed well. (b) The same cat at a recheck 6 months later. There appears to be resolution of the inflammation. © 2013 British Small Animal Veterinary Association

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7.11 (a) This 6-year-old DSH cat had been treated for chronic gingivostomatitis 3 months previously by extraction of the PMs and molars, as well as the left maxillary canine. There is mild inflammation caudally, although all the extraction sites appear to have healed well. (b) The same cat at a recheck 6 months later. There appears to be resolution of the inflammation.

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Full-size downloadable chart available to BSAVA members at www.bsava.com.

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Full-size downloadable chart available to BSAVA members at www.bsava.com. Full-size downloadable chart available to BSAVA members at www.bsava.com.

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The periodontal probe is held in a modified pen grip, as with all dental instruments except elevators and luxators. Graduations (millimetres) are marked on the end of a periodontal probe to enable measurements of the gingival sulcus.

The periodontal probe is held in a modified pen grip, as with all dental instruments except elevators and luxators. Graduations (millimetres) are marked on the end of a periodontal probe to enable measurements of the gingival sulcus. © 2013 British Small Animal Veterinary Association

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The periodontal probe is held in a modified pen grip, as with all dental instruments except elevators and luxators. Graduations (millimetres) are marked on the end of a periodontal probe to enable measurements of the gingival sulcus. The periodontal probe is held in a modified pen grip, as with all dental instruments except elevators and luxators. Graduations (millimetres) are marked on the end of a periodontal probe to enable measurements of the gingival sulcus.

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Differently shaped dental explorer probes.

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Differently shaped dental explorer probes. Differently shaped dental explorer probes.

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Using a periodontal probe to measure gingival sulcus depth around the distal root of the right maxillary 3rd PM. The probe has advanced 3 mm into the gingival sulcus, whereas the normal pocket depth in a cat should be <0.5 mm, indicating periodontal disease (the periodontal pocket depth should be recorded on the dental chart). Note also the fractured tip of the right maxillary canine.

Using a periodontal probe to measure gingival sulcus depth around the distal root of the right maxillary 3rd PM. The probe has advanced 3 mm into the gingival sulcus, whereas the normal pocket depth in a cat should be <0.5 mm, indicating periodontal disease (the periodontal pocket depth should be recorded on the dental chart). Note also the fractured tip of the right maxillary canine. © 2013 British Small Animal Veterinary Association

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$Image of Using a periodontal probe to measure gingival sulcus depth around the distal root of the right maxillary 3rd PM. The probe has advanced 3 mm into the gingival sulcus, whereas the normal pocket depth in a cat should be <0.5 mm, indicating periodontal disease (the periodontal pocket depth should be recorded on the dental chart). Note also the fractured tip of the right maxillary canine.$

Using a periodontal probe to measure gingival sulcus depth around the distal root of the right maxillary 3rd PM. The probe has advanced 3 mm into the gingival sulcus, whereas the normal pocket depth in a cat should be <0.5 mm, indicating periodontal disease (the periodontal pocket depth should be recorded on the dental chart). Note also the fractured tip of the right maxillary canine. Using a periodontal probe to measure gingival sulcus depth around the distal root of the right maxillary 3rd PM. The probe has advanced 3 mm into the gingival sulcus, whereas the normal pocket depth in a cat should be <0.5 mm, indicating periodontal disease (the periodontal pocket depth should be recorded on the dental chart). Note also the fractured tip of the right maxillary canine.

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The gingiva starts to bleed when probed. This should be graded for every tooth in the mouth (see Gingivitis index on dental chart).

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The gingiva starts to bleed when probed. This should be graded for every tooth in the mouth (see Gingivitis index on dental chart). The gingiva starts to bleed when probed. This should be graded for every tooth in the mouth (see Gingivitis index on dental chart).

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The periodontal probe is passed horizontally between the distal and the mesial roots of the maxillary 4th PM. The probe passes the whole way through, indicating complete exposure of the furcation of this tooth.

The periodontal probe is passed horizontally between the distal and the mesial roots of the maxillary 4th PM. The probe passes the whole way through, indicating complete exposure of the furcation of this tooth. © 2013 British Small Animal Veterinary Association

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The periodontal probe is passed horizontally between the distal and the mesial roots of the maxillary 4th PM. The probe passes the whole way through, indicating complete exposure of the furcation of this tooth. The periodontal probe is passed horizontally between the distal and the mesial roots of the maxillary 4th PM. The probe passes the whole way through, indicating complete exposure of the furcation of this tooth.

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Using an explorer probe to check for defects in the crown in a different cat. A FORL is visible on the right mandibular 4th PM.

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Using an explorer probe to check for defects in the crown in a different cat. A FORL is visible on the right mandibular 4th PM. Using an explorer probe to check for defects in the crown in a different cat. A FORL is visible on the right mandibular 4th PM.

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Using forceps to crack off a large piece of calculus from the left maxillary 4th PM tooth.

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Using forceps to crack off a large piece of calculus from the left maxillary 4th PM tooth. Using forceps to crack off a large piece of calculus from the left maxillary 4th PM tooth.

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Ultrasonic scaler in use. The side of the tip is used against the tooth surface and the fine water spray can be seen. Here the buccal surface of the uppermost maxillary canine is undergoing descaling.

Ultrasonic scaler in use. The side of the tip is used against the tooth surface and the fine water spray can be seen. Here the buccal surface of the uppermost maxillary canine is undergoing descaling. © 2013 British Small Animal Veterinary Association

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Ultrasonic scaler in use. The side of the tip is used against the tooth surface and the fine water spray can be seen. Here the buccal surface of the uppermost maxillary canine is undergoing descaling. Ultrasonic scaler in use. The side of the tip is used against the tooth surface and the fine water spray can be seen. Here the buccal surface of the uppermost maxillary canine is undergoing descaling.

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Scaling the palatal surface of the opposite maxillary canine.

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Scaling the palatal surface of the opposite maxillary canine. Scaling the palatal surface of the opposite maxillary canine.

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Following the scale and polish, FORLs (green lines) can now be seen on the distal root and crown of the right maxillary 3rd PM as well as at the furcation. Gingival recession (black lines) can also be seen, e.g. on the right maxillary 4th PM.

Following the scale and polish, FORLs (green lines) can now be seen on the distal root and crown of the right maxillary 3rd PM as well as at the furcation. Gingival recession (black lines) can also be seen, e.g. on the right maxillary 4th PM. © 2013 British Small Animal Veterinary Association

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Following the scale and polish, FORLs (green lines) can now be seen on the distal root and crown of the right maxillary 3rd PM as well as at the furcation. Gingival recession (black lines) can also be seen, e.g. on the right maxillary 4th PM. Following the scale and polish, FORLs (green lines) can now be seen on the distal root and crown of the right maxillary 3rd PM as well as at the furcation. Gingival recession (black lines) can also be seen, e.g. on the right maxillary 4th PM.

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An example of a tray of instruments. Not all instruments listed are shown in the photograph. From the right hand side: extraction forceps; Super Slim and Couplands elevators; periosteal elevator.

An example of a tray of instruments. Not all instruments listed are shown in the photograph. From the right hand side: extraction forceps; Super Slim and Couplands elevators; periosteal elevator. © 2013 British Small Animal Veterinary Association

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An example of a tray of instruments. Not all instruments listed are shown in the photograph. From the right hand side: extraction forceps; Super Slim and Couplands elevators; periosteal elevator. An example of a tray of instruments. Not all instruments listed are shown in the photograph. From the right hand side: extraction forceps; Super Slim and Couplands elevators; periosteal elevator.

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Sectioning the right mandibular 4th PM with a bur

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Sectioning the right mandibular 4th PM with a bur Sectioning the right mandibular 4th PM with a bur

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A Couplands 1 elevator being used on the right maxillary canine.

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A Couplands 1 elevator being used on the right maxillary canine. A Couplands 1 elevator being used on the right maxillary canine.

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