Currently set to Index
Currently set to Follow

Veterinary Dentistry Dental Cases

Demystifying Dentigerous Cysts in Dogs: Diagnosis, Surgical Approach, and Potential Complications

Dentigerous cysts, also known as follicular cysts, are odontogenic cysts that develop around the crown of an unerupted tooth. While relatively uncommon in dogs, they can cause significant bone expansion and discomfort, requiring surgical intervention. This blog post will delve into the diagnosis, surgical approach, and potential complications associated with dentigerous cysts in dogs, providing insights for both pet parents and veterinary practitioners.


Understanding Dentigerous Cysts: Development and Clinical Presentation

Dentigerous cysts arise from the enamel organ, a structure responsible for tooth enamel formation. Fluid accumulation between the enamel organ and the tooth crown leads to cyst formation and subsequent bone expansion. These cysts typically involve unerupted teeth, most commonly affecting the mandibular canine teeth, maxillary canine teeth, and mandibular first premolars in dogs.

Clinical signs of a dentigerous cyst may include facial swelling, malocclusion, difficulty eating, and pain. The cyst may sometimes become infected, leading to additional symptoms like fever, lethargy, and purulent discharge.


Diagnostic Tools: Radiography and Histopathology

Histopathological examination of the excised cyst lining is crucial to confirm the diagnosis and rule out other pathological processes, such as ameloblastomas, which can have a similar radiographic appearance. Ameloblastomas are locally invasive, potentially aggressive tumors that require more extensive surgical treatment compared to dentigerous cysts.

Veterinary dental radiographs are essential for diagnosing dentigerous cysts and evaluating their extent. They typically reveal a well-defined, unilocular radiolucent area surrounding the crown of an unerupted tooth. Due to cyst expansion, the affected tooth may be displaced within the bone.


A Case Study: An 18-Month-Old Golden Retriever Dog

A dentigerous cyst is an odontogenic cyst which means that it is derived from tissue that is responsible for forming the tooth. A missing tooth is the first indication that a cyst may be present. Veterinary dental radiography should always be performed when unexplained missing teeth are detected. Dentigerous cysts may also occur in cats but are recognized less commonly than in dogs.

This 18-month-old Golden Retriever dog presented for a missing right mandibular canine tooth (404), 3rd incisor (403), and 2nd incisor (402)


An unerupted canine tooth

Question: What additional findings are present radiographically?

Answer: Two abnormal tooth structures (impacted teeth 402 and 403) can be identified rostral to the impacted canine (404) crown. Linear lucencies are present dorsal and ventral to the canine tooth root.

Radiographic image revealing two impacted teeth (402 and 403) rostral to the unerupted canine (404) crown, with linear lucencies present dorsal and ventral to the canine tooth root, suggesting dentigerous cyst in dog


Veterinary dental radiograph showing two abnormal tooth structures (402 and 403) rostral to the impacted canine (404) crown, and linear lucencies dorsal and ventral to the canine tooth root, requiring surgical extraction for treatment of dentigerous cyst in dog

Question: What is the course of action?

Answer: The unerupted (e.g., impacted) tooth structures are at risk for odontogenic cyst (e.g., dentigerous cyst) formation and surgical extraction of all unerupted tooth structures and elimination of any cystic tissue is the treatment of choice.


A lateral approach ventral to the mucogingival line within the vestibular mucosa was utilized as shown. A #4 round bur was used to carefully remove vestibular bone to outline the canine tooth. An elevator was used to carefully extract the canine tooth.

Question: What abnormal finding do you see in the post-extraction radiograph?

Answer: An additional abnormal tooth structure is present mesial to the right mandibular first premolar (405)​

Radiographic image revealing two impacted teeth (402 and 403) rostral to the unerupted canine (404) crown, with linear lucencies present dorsal and ventral to the canine tooth root, suggesting dentigerous cyst in dog


Post-extraction radiograph revealing an additional abnormal tooth structure mesial to the right mandibular first premolar (405) in a dog undergoing surgical treatment for dentigerous cyst

All three abnormal tooth structures were removed. Cyst material is seen here, adhered to the larger tooth remnant post removal.


4-0 monocryl was used to close the defect utilizing a simple interrupted pattern.

Extracted abnormal tooth structures and adherent cyst material post-removal during surgical treatment of dentigerous cyst in an 18-month-old Golden Retriever dog


Post-operative – Summary

Surgical closure using 4-0 monocryl in a simple interrupted pattern following extraction of impacted teeth and removal of dentigerous cyst in a dog, to prevent self-trauma and promote healing

An elizabethan collar was placed to eliminate the possibility of self-trauma that could result in dehiscence. The histopath diagnosis was a dentigerous cyst.


Surgical Approach: Excision and Considerations

The treatment of choice for dentigerous cysts is surgical excision. The specific approach depends on the size and location of the cyst, as well as the involvement of adjacent teeth. In general, the following steps are involved:

  • Incision and Exposure: An incision is made over the affected area, typically extending beyond the cyst margins to ensure adequate exposure. The overlying soft tissues are carefully elevated to expose the bony cyst wall.

  • Cyst Removal: A periosteal elevator is used to gently separate the cyst lining from the surrounding bone. Care must be taken to avoid damaging adjacent vital structures, such as nerves and blood vessels.

  • Bone Debridement: A high-speed handpiece with a diamond bur is used to remove any remaining cyst remnants and smooth the bony edges. This step helps prevent cyst recurrence and promotes optimal healing.

  • Tooth Management: The involved unerupted tooth is typically extracted along with the cyst. In some cases, if an erupted tooth has a healthy root apex and is not significantly involved in the cyst, it may be retained after thorough debridement.

  • Closure: The surgical site is closed with absorbable sutures in a simple interrupted pattern.


Potential Complications and Postoperative Care

While generally straightforward, surgical excision of dentigerous cysts can present some potential complications, including:

  • Hemorrhage: Bleeding during surgery is managed with pressure, hemostatic agents, and meticulous surgical technique.

  • Nerve Damage: Damage to nearby nerves, particularly the mandibular nerve, can occur during cyst removal, leading to temporary or permanent loss of sensation in the affected area.

  • Fracture: Thinning of the bone due to cyst expansion increases the risk of fracture during surgery or postoperatively.

  • Recurrence: Incomplete removal of the cyst lining can lead to recurrence. Postoperative care typically involves pain management, antibiotics to prevent infection, and close monitoring for complications. Radiographs may be taken at follow-up appointments to assess healing and ensure complete cyst removal.


Additional Considerations and Resources

  • Advanced Imaging: In complex cases, advanced imaging modalities such as computed tomography (CT) scans may be helpful for precise assessment of cyst size, location, and involvement of surrounding structures.

  • Referral to a Veterinary Dentist: For challenging cases or those requiring specialized expertise, referral to a board-certified veterinary dentist is recommended.

  • Client Education: Clear communication with pet owners about the diagnosis, treatment options, and potential complications is essential for informed decision-making and optimal patient care.


Conclusion: A Multifaceted Approach for Optimal Outcomes

Dentigerous cysts in dogs require a multifaceted approach, involving accurate diagnosis, meticulous surgical technique, and comprehensive postoperative care. Early recognition and intervention are crucial for minimizing complications and achieving successful outcomes. By understanding the nature of these cysts and the intricacies of their management, veterinary professionals can provide optimal care for their canine patients, restoring oral health and improving their quality of life.


References:

  1. Verstraete FJM, Kass PH, Ligthelm AJ. Dentigerous cysts in dogs and cats: a review of 88 cases (1989-1999). J Vet Dent. 2000 Jun;17(2):55-8. doi: 10.1177/089875640001700201. PMID: 10883785.

  2. Gardner DG. Evolving concepts of odontogenic cysts and tumors. Oral Oncol. 1996 Sep;32(5):301-6. doi: 10.1016/0964-1955(96)00011-0. PMID: 8919499.

  3. Niemiec BA. Oral tumors in small animals. Merck Veterinary Manual. https://www.merckvetmanual.com/digestive-system/dentistry/oral-tumors-in-small-animals

  4. Soukup JW, Snyder CJ, Simmons BT. Odontogenic Cysts. Clinician’s Brief. https://www.cliniciansbrief.com/article/odontogenic-cysts

  5. Brook Niemiec, DVM, DAVDC, FAVD. The skinny on jaw cysts. Animal Dental Care Blog. https://animaldentalcare.com/blog/the-skinny-on-jaw-cysts/

Veterinary Dental On-Demand Online Courses

The Canine Dentistry Online Course
Comprehensive Feline Dentistry Online Course
Simple and Surgical Extractions in the Dog and Cat Online Course
Comprehensive Veterinary Dental Radiongraphic Interpretation Course
Veterinary Dentistry for the Veterinary Technician Online Course

FIND OUT WHY

OUR FRIENDS ARE SMILING

Dr. Erin V. Abarahams's Review for Dr. Brett Beckman's Veterinary Dental Webinars On Demand Online Dentistry Courses
Dr. Greg Wolfus's Review for Dr. Brett Beckman's Veterinary Dental Webinars On Demand Online Dentistry Courses
Dr. Farshid Kiaei's Review for Dr. Brett Beckman's Veterinary Dental Webinars On Demand Online Dentistry Courses
Dr. Kayla Simpson's Review for Dr. Brett Beckman's Veterinary Dental Webinars On Demand Online Dentistry Courses