Evaluation of the diagnostic yield of dental radiography and cone-beam computed tomography for the identification of dental disorders in small to medium-sized brachycephalic dogs

Intraoral Radiographic Interpretation Agreement Between Veterinary Students, Veterinary Dental Residents and Veterinary Dental Specialists

This study evaluated observer variations in the interpretation of radiographic evidence for periodontal disease, tooth resorption, and endodontic disease in dogs. Forty dental radiographs were evaluated for 12 different parameters (periapical destruction of bone, wider than expected root canal, narrower than expected root canal, apical root resorption, loss of alveolar bone, external surface resorption, external replacement resorption, external inflammatory resorption, external cervical root resorption, internal surface resorption, internal replacement resorption, internal inflammatory resorption). Interpretations by 20 veterinary dentists, 10 veterinary dental residents, and 10 veterinary students were analyzed for consistency within groups and between groups by intraclass correlation coefficients (ICCs [95% CI]). Additionally, the agreement rate between groups compared to histopathological diagnosis, when available, and to a consensus group were evaluated. The results showed fair to good interobserver agreement for all participants when looking at all questions simultaneously (0.578 [0.515-0.635]) and with the consensus group (0.483 [0.451-0.517]). However, questions pertaining to various types of tooth resorption scored the lowest ICCs ranging from 0.005 (-0.311 to 0.321) to 0.189 (-0.105 to 0.402) across individual groups. Students had the lowest agreement compared to the consensus group for all questions (0.383 [0.347-0.421]) with fair to good agreement involving groups of residents (0.501 [0.465-0.538]), recently boarded diplomates (0.541 [0.506-0.578]), and more experienced diplomates (0.545 [0.510-0.582]). While dental radiographs are essential for clinical decision making, this study shows that interpretation of radiographs is highly subjective.

Breed-Specific Skull Morphology Reveals Insights into Canine Optic Chiasm Positioning and Orbital Structure through 3D CT Scan Analysis

This study's CT scan-based morphometric analysis of 50 adult dogs explored the relationship between skull shape variations (determined by the skull index, SI), optic chiasm, optic canals, and orbital shape. Dogs were classified as brachycephalic (SI ≥ 59), mesocephalic (SI ≥ 51 but <59), and dolichocephalic (SI < 51). No significant age or weight differences were observed. Skull lengths (brachycephalic: 11.39 ± 1.76 cm, mesocephalic: 15.00 ± 2.96 cm, dolichocephalic: 17.96 ± 3.44 cm) and facial lengths (brachycephalic: 3.63 ± 1.00 cm, mesocephalic: 6.46 ± 1.55 cm, dolichocephalic: 8.23 ± 1.03 cm) varied significantly, with shorter orbital depths (brachycephalic: 2.58 ± 0.42 cm, mesocephalic: 3.19 ± 0.65 cm, dolichocephalic: 3.61 ± 0.77 cm) in brachycephalic dogs. The optic chiasm-to-inion horizontal length ratio to cranial horizontal length positively correlated with the SI (r = 0.883, p < 0.001), while the ratio to neurocranial length showed no SI correlation (range: 55.5-75.0). Brachycephalic breeds had a significantly wider optic canal angle (93.74 ± 16.00°), along with broader lacrimal-zygomatic and zygomatic frontal process angles. These findings highlight the zygomatic bone's role in influencing breed-specific orbital variations by connecting the face to the neurocranium, projecting the orbital rim outward and forward with facial shortening.

The Anatomy of the Stomatognathic System in Different Skull Types in Dogs

The anatomy of the stomatognathic system is important for both clinical evaluations and surgical approaches in all animal species. The aim of this study was to describe the innervation and vascularization of the stomatognathic system of the dog. Twelve dogs without a history of disease or cranial malformation were used: 4 brachycephalic, 4 mesocephalic, and 4 dolichocephalic. The dogs were dissected, and arteries, veins, and nerves related to the masticatory and swallowing components were identified. The distribution pattern of these structures in the 3 different skull types were observed. The entire blood supply of the stomatognathic system is derived from the external carotid artery, which originates from the common carotid artery, and terminates as it branches into the superficial temporal and maxillary arteries. The other main branches of the common carotid artery are the occipital, cranial laryngeal, ascending pharyngeal, lingual, facial, caudal auricular, and parotid arteries. Blood drainage was achieved via the external jugular vein, which originates from the union of the linguofacial and maxillary veins. Brachycephalic dogs had blood vessels with greater sinuosity (more deviations) when compared to dolichocephalic and mesocephalic dogs. The stomatognathic system innervation of brachycephalic skull dogs showed differences in the distribution of the facial nerve in the labial commissure and maxillary and mandibular regions. The cranial conformation of dogs demonstrated anatomical variations of the vascular and neural structures of the stomatognathic system. This data may be useful to improve clinical practice, surgical planning, and interpretation of clinical dysfunctions.

Prevalence of root fusion in canine maxillary second molar teeth using cone-beam computed tomography

This study evaluated the prevalence of root fusion in the right and left maxillary second molar teeth in dogs using cone-beam computed tomography (CBCT). A total of 180 dog CBCT scans, or a total of 360 maxillary second molar teeth, were analyzed in this study. Dogs were divided into weight categories of small (<10 kg), medium (10-25 kg), and large (>25 kg). Skull type (brachycephalic, mesocephalic, dolichocephalic) and sex were also recorded for each dog. Overall, 65% of maxillary second molar teeth had some type of root fusion. Of the teeth that had fusion, the only configuration represented was fusion of the distobuccal root with the palatal root. The most common root morphology overall (all dogs and both right and left maxillary second molar teeth included) was partial fusion (177/360, 49%). With the high prevalence of fused roots in maxillary second molar teeth in dogs found in this study, CBCT will help clinicians to more accurately assess a dog's anatomy and implications for treatment.

Diagnosis and Management of Furcation Lesions in Dogs - A Review

The furcation is the anatomic area where the roots divide on a multirooted tooth. Periodontal disease causing alveolar bone loss can lead to furcation lesions of various stages. Once furcation involvement has occurred, the area can be more difficult to clean or treat due to the complex anatomy and morphology of furcations. Teeth with short root trunks, longer tooth roots, and roots with wide furcation entrance areas/degrees of separation and wide root divergence are considered better candidates for long term maintenance. Dog teeth possess many of these advantageous anatomic features compared to human teeth. Treatment options for teeth with furcation lesions include: closed debridement, open debridement, furcation plasty, tunneling, partial tooth or root resection, root separation (hemisection or trisection), regenerative therapies, or exodontia. There are many factors to consider in determining treatment options. The favorable and unfavorable characteristics for maintenance of teeth with furcation lesions are summarized. Home care and ongoing professional care are important aspects of periodontal disease control for any patient. Studies of systemic and local antibiotic therapies in human patients have not demonstrated reduction of furcation stages, and probiotic effects at furcation sites have not been specifically examined. Human review studies show that most molar teeth once deemed "hopeless" due to stage 3 furcation lesions can be maintained for at least 5 to 15 years with supportive periodontal therapy. Similar long term studies in dogs are needed to improve the evidence-based management of canine patients with furcation lesions.

Designing and Equipping a Modern Dentistry and Oral Surgery Suite

Veterinary practices should consider designing and equipping a dedicated space to provide companion animal dental and oral surgical care. A single or multi-table dental suite design will allow organized and efficient delivery of dental care. Each workstation should be equipped with a procedural table that will allow for drainage, shadow-free procedural lighting, an anesthetic machine with monitoring, thermal support, anesthetic scavenger system, dental radiographic equipment, and an air-driven dental delivery system. Lift tables, dental-specific seating, swivel handpieces, and headlamp/surgical loupe lighting should also be considered to improve ergonomics.

Patient Triage, First Aid Care, and Management of Oral and Maxillofacial Trauma

Maxillofacial trauma is a common presentation in veterinary medical practice. Accurate assessment, diagnostics, pain management, and finally repair are tenants to treatment. In addition to typical tenants for fracture repair, the restoration of occlusion and return to function (eating, drinking, grooming) are unique to trauma management in these patients. Options for repair include conservative management (tape muzzles), noninvasive repair techniques (interdental wiring and composite splinting), and invasive repair techniques (interfragmentary wiring and plate and screw fixation).

Localization of the First Mandibular Molar Roots in Relationship to the Mandibular Canal in Small Breed Dogs-A Tomography Imaging Study

The intimate relationship between the mandibular canal (MC) and the first mandibular molar tooth presents challenges when performing dentoalveolar surgical procedures due to the probability of causing iatrogenic injury to the inferior alveolar neurovascular bundle. Superimposition between the MC and the first molar (M1) tooth roots is often observed on intraoral dental radiographs in small breed dogs. However, due to the radiograph's bidimensional nature, it is impossible to determine the buccal or lingual localization of the first molar roots with respect to the MC. Thus, this study's objective was to determine the localization of the first molar tooth's roots in relation to the position of the MC and their overlapping percentage with the canal in small-bodyweight dogs (<15 kg) using tomographic diagnostic images. For this, cone-beam computed tomography and high-definition computed tomography exams from 103 small breed dogs (under 15 kg) were retrospectively assessed to determine the lingual or buccal localization of the first molar tooth's roots with respect to the MC and the degree of overlap of the roots with the canal. In conclusion, most of the roots of M1 of dogs under 15 kg were located at the MC's lingual aspect (82.7%) with an overall superimposition median with the MC of 100 and 90% for the mesial and distal roots, respectively. Straddle tooth roots were not a common anatomical presentation in the dogs of this study.

Analysis of the Anatomic Relationship Between the Mandibular First Molar Roots and Mandibular Canal Using Cone-Beam Computed-Tomography in 101 Dogs

The mandibular first molar (M1) tooth of the dog is commonly involved in dental procedures. Tooth roots and the mandibular canal can vary in location, which has not been described on a large scale. The objective of this study was to describe the three-dimensional anatomic relationship of the mandibular M1 tooth roots and the mandibular canal in dogs. Cone-beam computed tomography (CBCT) was used to evaluate the anatomic relationship between the M1 tooth roots and the mandibular canal. CBCT images were collected from 101 canine cadaver heads from a variety of unknown breeds. All skulls used in this study were mesaticephalic, confirmed by facial index calculations. The position of the apex in relation to the mandibular canal and in relation to the buccal and lingual cortices was recorded and analyzed in relation to mandibular bone height: root length ratio. When evaluating the apex in a buccal-lingual relationship, the tooth roots were found to be located closer to the lingual cortex in 73.3% of M1 roots. Tooth root apical positions were found to be symmetric between the right and left side of the mouth in 93% of mesial roots and 95% of distal roots. Apical positions relative to the mandibular canal within the same tooth were found to be consistent in 52% of teeth. Teeth with roots dorsal to the mandibular canal were associated with the largest mandibular bone height: root length ratio. CBCT provides a more precise overview than dental radiographs of three-dimensional anatomy. The tooth root position can be estimated in a clinical setting based on the ratio of mandibular bone height to tooth root length obtained from intraoral radiographs. Understanding the relative location of important anatomic structures is key to avoiding complications associated with various dental procedures. This study has documented that assessing anatomic structures with 2D imaging alone is flawed, and the large majority of dogs have M1 roots closer to the lingual aspect than the buccal aspect of the mandible.

Diagnostic Yield of Dental Radiography and Cone-Beam Computed Tomography for the Identification of Anatomic Structures in Cats

The objective of this study was to evaluate the diagnostic yield of dental radiography (DR) and 3 cone-beam computed tomography (CBCT) methods for the identification of predefined anatomic structures in cats. For 5 feline cadaver heads and 22 client-owned cats admitted for evaluation and treatment of dental disease, a total of 22 predefined anatomic structures were evaluated separately by use of the DR method and 3 CBCT software modules [multiplanar reconstructions (MPR), tridimensional (3-D) rendering, and reconstructed panoramic views (Pano)]. A semi quantitative scoring system was used, and mean scores were calculated for each anatomic structure and imaging method. The Friedman test was used to evaluate values for significant differences in diagnostic yield. For values that were significant the Wilcoxon signed rank test was used with the Bonferroni-Holm multiple comparison adjustment to determine significant differences among each of the possible pairs of diagnostic methods. Differences of diagnostic yield among the DR and 3 CBCT methods were significant for 17 of 22 anatomic structures. For these structures, DR scores were significantly higher than scores for Pano views for 2 of 17 structures, but DR scores were significantly lower than scores for Pano views for 6 anatomic structures, tridimensional rendering for 10 anatomic structures, and MPR for 17 anatomic structures. In conclusion, it was found that CBCT methods were better suited than DR for the identification of anatomic structures in cats. Results of this study can serve as a basis for CBCT evaluation of dentoalveolar and other maxillofacial bony lesions in cats.

The Diagnostic Yield of Dental Radiography and Cone-Beam Computed Tomography for the Identification of Dentoalveolar Lesions in Cats

The objective of this study was to evaluate the diagnostic yield of dental radiography (DR) and 3 cone-beam computed tomography (CBCT) software modules for the identification of 32 pre-defined dentoalveolar lesions in cats. For 5 feline cadaver heads and 22 client-owned cats admitted for evaluation and treatment of dental disease, 32 predefined dentoalveolar lesions were evaluated separately and scored by use of dental radiography and 3 CBCT software modules [multiplanar reconstructions (MPR), tridimensional (3-D) rendering, and reconstructed panoramic views]. A qualitative scoring system was used. Dentoalveolar lesions were grouped into 14 categories for statistical analysis. Point of reference for presence or absence of a dentoalveolar lesion was determined as the method that could be used to clearly identify the disorder as being present. Accuracy, sensitivity, specificity, and positive and negative predictive values were calculated with the McNemar χ2 test of marginal homogeneity of paired data. When all 3 CBCT software modules were used in combination, the diagnostic yield of CBCT was significantly higher than that of dental radiography for 4 of 14 categories (missing teeth, horizontal bone loss, loss of tooth integrity, feline resorptive lesions), and higher, although not significantly so, for 9 categories (supernumerary teeth, supernumerary roots, abnormally shaped roots, vertical bone loss, buccal bone expansion, periapical disease, inflammatory root resorption, and external replacement root resorption). In conclusion, we found that CBCT provided more clinically relevant detailed information as compared to dental radiography. Therefore, CBCT should be considered better suited for use in diagnosing dentoalveolar lesions in cats.