# Cat Dental Chart: Feline Tooth Numbering A feline dental chart is only as good as the numbering system behind it. Learn the modified Triadan system and you can record every finding on any cat from a single mouth map: which tooth is missing, which one resorbs, which one fractured, and which one needs a radiograph before anyone touches it with an elevator. By the end of this guide you will be able to number all 30 permanent teeth and all 26 deciduous teeth, write a dental formula correctly, spot the four tooth positions cats lack relative to dogs, and log the four pathologies that dominate feline dentistry. **What you need on hand:** a printed or digital feline dental chart with the modified Triadan grid, a periodontal probe marked in millimeters, a curved explorer, intraoral radiography or cone beam computed tomography, and the patient's anesthesia record. Every tooth in the mouth must be charted, including teeth that are absent and teeth that are present. A chart that says "missing 108" is a clinical claim, not a diagnosis, because missing means you looked and did not see it. This article is educational and is not a substitute for veterinary diagnosis or treatment. ## What the modified Triadan system is and why it matters The modified Triadan system is a three-digit numbering convention for teeth that is accepted for veterinary dentistry and oral surgery [1]. It replaces tooth names with a number that tells you the quadrant and the position in one glance. Because cats have a fixed tooth count, the numbering is stable from patient to patient and across species, which is why it is the nomenclature used in feline oral anatomy and tooth extraction technique reviews [1]. The system has three digits: 1. **First digit = quadrant.** The mouth is divided into four quadrants by the midline between the upper and lower arches and between the left and right sides. 2. **Last two digits = tooth position.** Position numbers run from the front of the mouth toward the back, so 01 is the first tooth in the row and higher numbers sit further caudally. 3. **Left and right are defined from the patient's perspective, not the viewer's.** This is the step readers get wrong. When you look into the mouth from the front, the cat's right upper teeth appear on your left. The quadrants are: | First digit | Quadrant | What the clinician sees | |--|--|--| | 1 | Upper right (maxillary right) | Patient's right side, upper arcade | | 2 | Upper left (maxillary left) | Patient's left side, upper arcade | | 3 | Lower left (mandibular left) | Patient's left side, lower arcade | | 4 | Lower right (mandibular right) | Patient's right side, lower arcade | So 104 is the upper right canine. 204 is the upper left canine. 304 is the lower left canine. 404 is the lower right canine. The last two digits are identical on all four because they are the same tooth position in a different quadrant. The modified Triadan system also applies to the deciduous dentition in many charting conventions, but deciduous teeth are frequently recorded with the same quadrant and position logic and flagged separately as deciduous, retained, or persistent. Persistent deciduous teeth are a common reason for extraction in dogs and cats, and a deciduous canine extraction study across both species found the technique is frequently performed [2]. Persistent deciduous canine teeth accounted for 178 of 305 extractions in that series [2]. ### The feline dental formula Permanent dentition: **I3/3 C1/1 P3/2 M1/1 per side**, for a total of **30 permanent teeth** [1]. Translate the formula one tooth at a time. The letters are incisor (I), canine (C), premolar (P), and molar (M). The number after the slash is the lower arcade count. I3/3 means three upper incisors and three lower incisors. C1/1 means one upper and one lower canine. P3/2 means three upper premolars and two lower premolars. M1/1 means one upper molar and one lower molar. Multiply by two sides and you get 30 teeth: 16 upper and 14 lower. Deciduous dentition: **26 deciduous teeth**, typically written with the same positional logic but fewer cheek teeth because cats do not have deciduous molars. The deciduous teeth are the ones that erupt first and are replaced by the permanent set. ### What cats lack compared with dogs This is the comparison that catches candidates on oral anatomy exams. **Cats have no upper first premolar, no lower first premolar, and no lower second premolar.** The upper arcade therefore has three premolars (positions 06, 07, and 08) plus one molar (position 09). The lower arcade has two premolars (positions 07 and 08) plus one molar (position 09). Cats do not lose a tooth to gain one, they simply have fewer cheek teeth than dogs at those positions. The cat also has no deciduous molars, which is why the deciduous count is lower than the permanent count while both arches keep the same incisor and canine formula. A canine dental chart and a feline dental chart are not interchangeable. If you fill a dog chart for a cat, you will mark teeth as absent that never existed, and you will create a false dental history in the record that could be repeated at every future visit. ## Building the numbered walkthrough: cat dental chart Follow this sequence during every anesthetized oral examination. Charting under anesthesia is standard because a conscious examination cannot reliably reveal all disease, and radiography and treatment both require anesthesia as part of feline oral care [3]. **Step 1. Set the chart orientation.** Confirm the chart is printed or displayed with the patient's right side on the viewer's left. If the software mirrors the image, stop and fix that first. A reversed chart is the single most common source of wrong tooth numbers. **Step 2. Start with 101 and count forward.** Call out tooth numbers in ascending order within each quadrant. The standard full-mouth sequence is upper right, upper left, lower left, lower right. **Step 3. Chart four values per tooth where applicable.** Mobility, probing depth in millimeters, furcation involvement, and any lesion category (resorption, fracture, missing, retained, or normal). **Step 4. Record findings as you go, not from memory.** If you find a fracture of 104, log 104 immediately. If you find 309 missing, log 309 missing with the note that the tooth may be extracted, unerupted, or truly absent, and confirm with radiography. **Step 5. Radiograph before extracting or diagnosing.** Intraoral radiography is the reference standard for confirming tooth resorption, retained roots, and periodontal bone loss. Two-thirds of cats in an exploratory study had tooth resorption confirmed by intraoral radiography, primarily affecting the mandibular first molars (409) and fourth premolars (108) [4]. **Expected output of a complete chart session:** every quadrant has 01 through 09 entered or explicitly marked as absent, every absent tooth has a radiographic note, and each pathology is tied to a specific tooth number rather than a region. If the record says "lower left molar" instead of "309," rewrite it. A worked example of a notation line looks like this: ``` Patient: 9-year-old domestic shorthair, female spayed Date: 2026-09-19 104 Fracture, complicated crown fracture with pulp exposure, VPT candidate or extraction 108 Tooth resorption, Stage 3, radiolucency extends to root 109 Normal 204 Normal 309 Missing, previously extracted (owner confirmed) 409 Tooth resorption, Stage 2, mandibular first molar ``` Notice that none of these entries say "molar" or "canine." The number replaces the name. ## The full feline permanent dentition table The table below maps every tooth number to its anatomy. Names use the modified Triadan convention: incisor, canine, premolar, molar, followed by the number-word and the arcade. | Tooth number | Tooth name | Notes | |--|--|--| | 101 | Right maxillary first incisor | | | 102 | Right maxillary second incisor | | | 103 | Right maxillary third incisor | | | 104 | Right maxillary canine | Longest crown, frequent fracture site | | 105 | Right maxillary first premolar | Absent in cats | | 106 | Right maxillary second premolar | | | 107 | Right maxillary third premolar | | | 108 | Right maxillary fourth premolar | Carnassial tooth, common resorption site [4] | | 109 | Right maxillary first molar | | | 201 | Left maxillary first incisor | | | 202 | Left maxillary second incisor | | | 203 | Left maxillary third incisor | | | 204 | Left maxillary canine | Common fracture site, root relationship to nasolacrimal duct [5] | | 205 | Left maxillary first premolar | Absent in cats | | 206 | Left maxillary second premolar | | | 207 | Left maxillary third premolar | | | 208 | Left maxillary fourth premolar | Carnassial tooth | | 209 | Left maxillary first molar | | | 301 | Left mandibular first incisor | | | 302 | Left mandibular second incisor | | | 303 | Left mandibular third incisor | | | 304 | Left mandibular canine | | | 305 | Left mandibular first premolar | Absent in cats | | 306 | Left mandibular second premolar | Absent in cats | | 307 | Left mandibular third premolar | | | 308 | Left mandibular fourth premolar | Carnassial tooth | | 309 | Left mandibular first molar | Common resorption site [4] | | 401 | Right mandibular first incisor | | | 402 | Right mandibular second incisor | | | 403 | Right mandibular third incisor | | | 404 | Right mandibular canine | | | 405 | Right mandibular first premolar | Absent in cats | | 406 | Right mandibular second premolar | Absent in cats | | 407 | Right mandibular third premolar | | | 408 | Right mandibular fourth premolar | | | 409 | Right mandibular first molar | Common resorption site [4] | Numbering the rows in that table does not require all 30 rows to be filled. The table lists 30 permanent tooth positions because cats have 30 teeth, but six of those positions (105, 205, 305, 306, 405, and 406) are positions cats do not have. Writing "absent" in those rows is correct anatomy, not a chart error. This is the practical reason a feline dental chart must be a cat-specific chart rather than a shared small-animal chart. The deciduous count is 26, and deciduous teeth are charted with a separate label or software flag. Deciduous teeth are smaller, often narrower in crown, and can persist alongside a permanent tooth, producing a double set at a single position. Persistent deciduous teeth were the leading reason for deciduous canine extraction in one multi-site series [2]. ## Recording common feline pathology on the chart Four conditions account for most of the entries a feline dental chart will carry. Each one gets charted at a specific tooth number, and each one changes the treatment plan. ### Tooth resorption (TR) Tooth resorption is the loss of tooth structure through odontoclastic activity. It is one of the most common dental diseases of cats and a painful condition leading to tooth loss [6]. In a case-control study drawn from a Finnish feline health survey, the frequency of veterinarian-diagnosed TR was 3.9% across the whole survey population and 21% in the examined subpopulation, and risk increased with age [6]. In another retrospective review of 166 cats with radiographically confirmed TR, mandibular premolars and molars were most commonly affected [7]. Charting TR requires more than marking the tooth. The lesion needs a stage or grade, and it needs confirmation with intraoral radiography, because the clinical crown can look nearly normal while the root is destroyed below the gingival margin [4]. Two-thirds of cats in an exploratory study of the oral-renal axis had TR, and the same study found an association between higher serum symmetric dimethylarginine (SDMA) concentrations and the presence of resorptive lesions [4]. The chart entry should read: tooth number, stage, and whether the root is salvageable. A common error is to chart TR on 409 and then extract without radiographing the neighboring 408 and 308, which are frequently involved in the same mouth. Extractions in cats are predominantly performed for tooth resorption, chronic gingivostomatitis, and periodontal disease [1]. ### Periodontal disease Periodontal disease is the inflammation and progressive loss of the tissues that hold the teeth in the jaws [1]. In a study that classified the primary reason for every extraction in a large feline population, periodontitis was the most frequent reason at 33.41%, followed by feline chronic gingivostomatitis at 32.40% and tooth resorption at 15.21% [8]. Periodontitis and TR both increased with age in that population [8]. Periodontitis was most commonly observed in the maxillary first molar teeth and mandibular incisor teeth and least frequently in the canine teeth [8]. Charting periodontal disease means recording a probing depth in millimeters for each tooth surface, plus furcation involvement on multi-rooted teeth and mobility. The clinical attachment loss is what determines whether a tooth is treated or extracted. Gingivitis alone is reversible, and the Feline Veterinary Medical Association guidelines list early-onset gingivitis as one of the most commonly encountered feline oral conditions requiring targeted care [3]. Two adjacent teeth in the table above are common offenders. 109 (right maxillary first molar) and 209 (left maxillary first molar) are the maxillary teeth most often cited for periodontitis [8]. If you chart 209 with a deep pocket, probe 208 as well. ### Feline chronic gingivostomatitis (FCGS) Feline chronic gingivostomatitis is a debilitating inflammatory condition characterized by severe inflammation of the caudal oral mucosa [9]. Treatment frequently requires extensive extraction, and full-mouth extraction or partial-mouth extraction is considered standard therapy, though reported clinical remission rates vary widely from 51.8% to 67.3% and many affected cats still need long-term immunomodulatory treatment [9]. FCGS was the second most common reason for extraction in the feline extraction study at 32.40% and showed a decreasing prevalence trend with age, unlike periodontitis and TR [8]. A case series of three cats with inflammation confined to one side of the caudal oral mucosa underwent unilateral partial-mouth extraction of the affected side, and all three achieved complete clinical remission [9]. This is a specific treatment strategy that must be documented on the chart with the tooth numbers removed, because follow-up evaluation depends on knowing exactly what was extracted. ### Fractured teeth, especially canines The maxillary canine is a long, prominent tooth with a root that sits in close association with the nasolacrimal duct in cats [5]. A complicated crown fracture with pulp exposure of 204 was reported in a 5-year-old Russian Blue cat, and the root canal therapy that followed produced retrograde passage of sodium hypochlorite through the nasolacrimal duct, causing chemical injury to the cornea and a corneal ulcer [5]. Clinicians managing maxillary canine endodontic cases should be aware of that route and should consider advanced imaging before treating [5]. Fracture charting has two components: which tooth, and whether the fracture is complicated (pulp exposed) or uncomplicated (pulp not exposed). Vital pulp therapy has been reported as a viable alternative to extraction or root canal therapy in cats with recent complicated crown fracture or traumatic malocclusion, with an 81% overall success rate across 47 teeth in 36 cats in one retrospective study [10]. That number is a study result from one referral clinic, not a guarantee for any individual tooth. Brachycephalic cats had a significantly higher prevalence of fractured teeth compared with non-brachycephalic cats in a photographic screening study of 775 cats, with an odds ratio of 1.95 [11]. Fractured teeth were among the abnormalities visible from labial and buccal photographs in both species, along with calculus, discoloration, missing teeth, and persistent deciduous teeth [11]. Clinical photography is a reasonable adjunct to charting, but it does not replace radiography. ## Clinical Relevance, Limitations and Common Mistakes Getting the number right matters beyond paperwork. A dental procedure in a cat carries real anatomic risk if the wrong tooth or wrong quadrant is treated. Retrobulbar abscessation, ascending bacterial optic neuritis, and bacterial meningoencephalitis were reported after a routine tooth extraction in a 12-year-old cat, confirmed at necropsy [12]. That case is rare, but it is a reminder that tooth identification and pre-extraction imaging are safety steps, not formalities. **Common mistakes worth naming.** 1. **Reversing the patient's left and right.** If the clinician charts 204 as the right maxillary canine, every downstream entry is wrong. Always define the quadrant from the patient's perspective. 2. **Mapping a dog chart onto a cat.** The first premolars (105, 205, 305, 405) and the lower second premolars (306, 406) do not exist in cats. 3. **Charting from memory after the procedure.** Write the number at the moment of the finding. 4. **Charting "missing" without a radiographic note.** Missing can mean extracted, unerupted, or resorbed to the gingival margin. 5. **Treating a resorptive tooth as a simple extraction.** Resorptive lesions change extraction planning, and extraction technique in cats is closely tied to the type and stage of resorption [1]. 6. **Skipping the caudal oral mucosa.** FCGS lesions sit in the caudal oral mucosa, not on a tooth crown, so a tooth-only chart will miss them [9]. **Limitations.** Charting captures what you can see and probe. Radiography and cone beam computed tomography add what you cannot see, including root resorption, retained roots, and periapical bone loss [4]. Patient size can affect risk in other ways: in a prospective cone beam CT study of 303 cats imaged for dental procedures, ear disease was an incidental finding in 41.4% of cats, and cats weighing 10 pounds or less were at higher risk of ear disease [13]. Advanced imaging during a dental workup can therefore reveal findings outside the mouth. Anesthesia is the enabling step, not an optional one. The 2025 Feline Veterinary Medical Association feline oral health and dental care guidelines note that further assessment under anesthesia is necessary for radiography and treatment, and that multimodal perioperative analgesia is standard for feline oral and dental care because these patients experience pain [3]. Chart a pain score alongside the tooth numbers. Individual cases need a veterinarian. This article teaches the numbering convention and the pathology categories, not a treatment decision for your cat. ## Frequently Asked Questions ### How many teeth does an adult cat have? An adult cat has 30 permanent teeth. The number comes from the formula I3/3 C1/1 P3/2 M1/1 per side, which gives 16 maxillary teeth and 14 mandibular teeth when both sides are counted. ### How many teeth does a kitten have? A kitten has 26 deciduous teeth, and all of them are replaced by the permanent set. The deciduous formula keeps the incisors and canines but lacks molars. ### What is the modified Triadan system in one sentence? It is a three-digit tooth numbering system in which the first digit is the quadrant (1 = upper right, 2 = upper left, 3 = lower left, 4 = lower right) and the last two digits are the tooth position counted from the front of the mouth. ### Which teeth do cats have that dogs do not? None. The difference runs the other way. Cats lack the maxillary first premolar, the mandibular first premolar, and the mandibular second premolar that dogs possess. ### Is 104 the upper right or upper left canine? The upper right canine is 104. The upper left canine is 204. The first digit is the quadrant defined from the patient's perspective, so 1 is the cat's right side. ### What is the most common reason for tooth extraction in cats? Periodontitis was the most frequent primary reason for extraction in a large feline population at 33.41%, followed by feline chronic gingivostomatitis at 32.40% and tooth resorption at 15.21%. ### Can you diagnose tooth resorption without a radiograph? No. Tooth resorption is confirmed with intraoral radiography because the clinical crown can appear near normal while the root is being destroyed below the gingival margin. ### Why does a maxillary canine extraction in a cat carry special risk? The maxillary canine root sits in close association with the nasolacrimal duct. Retrograde passage of an irrigant through that duct during endodontic treatment has caused chemical injury to the cornea. ## Related Articles - [Chinchilla Care: Overgrown Dental Spurs & Tooth Trimming Guide](/knowledge/veterinary-medicine/exotic-small-animals/chinchilla-care-overgrown-dental-spurs-tooth-trimming-guide) - [Hamster Care: Overgrown Dental Spurs & Tooth Trimming Guide](/knowledge/veterinary-medicine/exotic-small-animals/hamster-care-overgrown-dental-spurs-tooth-trimming-guide) - [Rabbit Care: Overgrown Dental Spurs & Tooth Trimming Guide](/knowledge/veterinary-medicine/exotic-small-animals/rabbit-care-overgrown-dental-spurs-tooth-trimming-guide) - [Ferret Care: Overgrown Dental Spurs & Tooth Trimming Guide](/knowledge/veterinary-medicine/exotic-small-animals/ferret-care-overgrown-dental-spurs-tooth-trimming-guide) - [Cockatiel Care: Overgrown Dental Spurs & Tooth Trimming Guide](/knowledge/veterinary-medicine/exotic-small-animals/cockatiel-care-overgrown-dental-spurs-tooth-trimming-guide) - [Guinea Pig Care: Overgrown Dental Spurs & Tooth Trimming Guide](/knowledge/veterinary-medicine/exotic-small-animals/guinea-pig-care-overgrown-dental-spurs-tooth-trimming-guide) - [How Many Teeth Do Cats Have? Feline Dental Guide](/knowledge/veterinary-medicine/veterinary-anatomy-physiology/how-many-teeth-do-cats-have-feline-dental-guide) - [How Many Teeth Do Dogs Have? Dental Anatomy Guide](/knowledge/veterinary-medicine/veterinary-anatomy-physiology/how-many-teeth-do-dogs-have-dental-anatomy-guide) - [Zenrelia Dosing Chart for Dogs and Side Effects](/knowledge/veterinary-medicine/pet-medication-guide/zenrelia-dosing-chart-for-dogs-and-side-effects) ## Sources 1. [Applied feline oral anatomy and tooth extraction techniques: an illustrated guide.](https://pubmed.ncbi.nlm.nih.gov/25344460/) 2. [Closed Extraction of Deciduous Canine Teeth Required Less Surgical Time Without Increased Complication Rate Compared to an Open Technique in Dogs and Cats.](https://pubmed.ncbi.nlm.nih.gov/41863488/) 3. [2025 FelineVMA feline oral health and dental care guidelines.](https://pubmed.ncbi.nlm.nih.gov/41319038/) 4. [Association Between Serum Symmetric Dimethylarginine and Tooth Resorption in Cats: An Exploratory Study on the Oral-Renal Axis.](https://pubmed.ncbi.nlm.nih.gov/41893652/) 5. [Complications of Intracanal Irrigation During Root Canal Therapy of a Maxillary Canine Tooth in a Cat.](https://pubmed.ncbi.nlm.nih.gov/39699018/) 6. [A large case-control study indicates a breed-specific predisposition to feline tooth resorption.](https://pubmed.ncbi.nlm.nih.gov/38740176/) 7. [Association of Skull Type, Diet, and Chronic Gingivostomatitis with Tooth Resorption in Cats Receiving Dental Treatment.](https://pubmed.ncbi.nlm.nih.gov/41514822/) 8. [The prevalence of reasons for tooth extraction in cats.](https://pubmed.ncbi.nlm.nih.gov/40727267/) 9. [Unilateral partial-mouth extraction achieves complete clinical remission in cats with unilateral caudal feline chronic gingivostomatitis: a case series.](https://pubmed.ncbi.nlm.nih.gov/42249348/) 10. [Vital Pulp Therapy in Cats: 47 Cases (2009-2025).](https://pubmed.ncbi.nlm.nih.gov/42159272/) 11. [Initial screening for dental abnormalities identified by labial and buccal photographs in dogs and cats.](https://pubmed.ncbi.nlm.nih.gov/38901457/) 12. [Ascending bacterial optic neuritis and meningoencephalitis following tooth extraction in a cat.](https://pubmed.ncbi.nlm.nih.gov/41398265/) 13. [Prevalence of ear disease in cats undergoing cone beam computed tomography for dental procedures.](https://pubmed.ncbi.nlm.nih.gov/40191083/)