Mandible and mandibular first molar tooth measurements in dogs: relationship of radiographic height to body weight.

Height measurements of the mandible and the mandibular first molar tooth were obtained from 234 dogs. Statistical analysis was performed to determine possible associations between these measurements and body weight, sex, age, and body condition. There was a statistically significant association between the mandible: mandibular first molar tooth height measurement ratio and body weight (p < 0.0001) in all body weight groups. Small dogs had proportionally larger mandibular first molar teeth relative to mandibular height compared with larger dogs. This relationship may contribute to an increased susceptibility in small dogs for periodontitis and subsequent tooth loss. There was no statistically significant association between the mandible: mandibular first molar tooth height measurement ratio and other parameters evaluated in this study.

Hepatitis C prevalence among Australian injecting drug users in the 1970s and profiles of virus genotypes in the 1970s and 1990s.

OBJECTIVES: To examine the seroprevalence of hepatitis C virus (HCV) in the Australian injecting drug-using community in the 1970s, and to compare the profile of HCV genotypes with that seen in the 1990s. DESIGN: Investigation of stored sera that were collected from injecting drug users in the 1970s and comparison with sera collected in the 1990s. SETTING: Inner Sydney, 1974-1975 and 1994-1996. PATIENTS: The 1970s group comprised 141 consecutive injecting drug users who attended the Brisbane Street Methadone Clinic. The 1990s group comprised 88 consecutive, injecting drug users of European origin who were HCV antibody-positive and attended a primary healthcare facility (the Kirketon Road Centre). MAIN OUTCOME MEASURES: HCV antibody prevalence (1970s); profile of HCV serotypes (1970s and 1990s); and serological evidence of hepatitis A and B. RESULTS: 84% of the 1970s group were HCV antibody-positive, of whom 92% were infected with HCV serotype 1 and 1% with serotype 3. In contrast, in the 1990s group, 69% were infected with HCV serotype 1 and 25% with serotype 3. The HCV-positive subjects from the early group were more likely than those from the recent group to have serological evidence of previous HBV infection. CONCLUSIONS: The high prevalence of HCV among injecting drug users in the 1970s in Australia confirms an epidemic that has been present for at least 25 years. Over this period, the proportion of HCV genotype 1 infections has decreased and genotype 3 infections have emerged.

Periodontal disease in dogs. Etiopathogenesis, prevalence, and significance.

Periodontal disease is very common and often very severe in dogs. It is caused by accumulation of bacterial plaque, particularly Gram-negative anaerobic rods. Tissue destruction results from autodegradation induced by the continuing inflammatory response. Small dogs are particularly at risk. Prevention by retarding accumulation of plaque is the key concept.

Radiographic study of the maxillary canine tooth in mesaticephalic dogs.

Radiology is the most important diagnostic technique for evaluation of the radicular structure of the tooth and adjacent areas. However, superimposition of other oral or nasal structures often creates difficulties when interpreting radiographic images. The purpose of this study was to identify and locate any anatomical structures that may be superimposed over the root of the maxillary canine tooth in radiographs of dogs. Results showed that the nasal conchae minimally interfere with the visualization of the tooth. The vomer bone and maxillary structures (the conchal crest, the line of conjunction between the maxillary body and the palatine process, and the palatine sulcus) are visible as linear radiopacities, and were found to be responsible for most of the radiographic features in this area. The incisivomaxillary canal and the palatine fissure caused radiolucent images. The incisivomaxillary suture and the nasoincisive suture may appear as radiolucent images in young skulls and linear radiopacities in older skulls. It appears from this study that a compromise between minimal superimposition of dental and non-dental structures and small image distortion is needed to obtain diagnostic radiographic views of the maxillary canine tooth in mesaticephalic dogs. The relative positions of the conchal crest, the line of conjunction between the vertical body of the maxilla and its palatine process, the incisivomaxillary canal, and the tooth, cannot be changed radiographically because of the close anatomic position of these structures.

Apical root canal anatomy of canine teeth in cats.

OBJECTIVE: To determine the apical anatomy of canine teeth in cats. SAMPLE POPULATION: 70 permanent canine teeth of cats. PROCEDURE: The teeth were extracted, cleaned, and radiographed, and the root canals were stained with India ink, then cleared in methyl salicylate. The apical root canal anatomy was studied by examining dental radiographs and microscopic measurements performed on the cleared specimens. RESULTS: Apical root canal anatomy in cats has the same "sprinkler-rose" appearance as seen in dogs. The mean length of the radiodense apex on radiographs was 2.8 +/- 1.2 mm. The mean lengths of the apical ramifications were 1.9 +/- 0.4 and 1.6 +/- 0.4 mm for upper and lower canine teeth, respectively; mean numbers of apical ramifications were 13 +/- 6 and 12 +/- 5, respectively; and mean ratios (length of ramifications/length of root) were 0.16 +/- 0.03 and 0.15 +/- 0.04, respectively. There was significant (P < 0.05) difference in the length of apical ramifications between upper and lower canine teeth and significant (P < 0.05) positive correlation between the length of the root and the length of apical ramifications for all canine teeth. CONCLUSION: Primary apical foramen is not present in mature canine teeth of cats. CLINICAL RELEVANCE: There is little risk of apical penetration by files during endodontic therapy of canine teeth of cats; however, the multiple foramina require that apical instrumentation is thorough to prevent soft tissue remnants causing failure of the procedure.

Correlation of diet, other chewing activities and periodontal disease in North American client-owned dogs.

In 1350 client-owned dogs in North America, the association of calculus, gingival inflammation and periodontal bone loss with diet (dry food only, or other than dry food only), and with access to other chewing materials was analyzed. There were few apparent differences seen in dogs fed dry food only compared with those fed other than dry food only. There was progressively less accumulation of calculus, less gingival inflammation and less periodontal bone loss in dogs that were given access to more types of chewing materials (rawhides, bones, biscuits, chew toys) compared with dogs given access to fewer or no chewing materials. When the effects of individual chewing materials were analyzed, access to rawhides overall had the greatest apparent periodontal protective effect, and this effect was more apparent in dogs fed dry food only compared with those fed other than dry food only.

Electronic programs and information on veterinary dentistry. Special report.

Veterinary dental materials (e.g. documents, images, continuing education courses, message boards, bibliographic search options) that are available as electronic media are described. These include materials available on the Internet or via commercial on-line services such as AOL-VIN and Compuserve-NOAH, and off-line materials such as CD-i, CD-ROM and floppy disk programs.

Association of periodontal disease and histologic lesions in multiple organs from 45 dogs.

Forty-five mixed breed dogs were evaluated for the presence and extent of periodontal disease. Histopathology was performed on samples of lung, myocardium, liver, kidney, tonsil, spleen, submandibular lymph node and tracheobronchial lymph node. Mitral valves were evaluated grossly. Statistical analysis was used to determine if there was a relationship between the extent of periodontal disease and histopathologic changes in the tissues examined. In the forty-five dogs studied, an association was found between periodontal disease and histopathologic changes in kidney, myocardium (papillary muscle), and liver.

Subgingival bacteria--comparison of culture results in dogs and cats with gingivitis.

Aerobic and anaerobic subgingival bacteria were cultured and identified from 49 dogs and 40 cats with spontaneous gingivitis. The most common organisms were gram-negative anaerobes (37% of canine isolates and 39% of feline isolates) and gram-positive aerobes (36% of canine isolates and 29% of feline isolates). No major differences were found between the subgingival floras of dogs and cats with gingivitis.

Antimicrobial susceptibility of subgingival bacterial flora in dogs with gingivitis.

The aerobic and anaerobic flora from gingival pockets of 49 dogs with severe gingivitis and periodontitis were cultured. The susceptibility of each isolate to four antimicrobial agents currently approved for veterinary use in the USA (amoxicillin-clavulanic acid; clindamycin; cefadroxil; and enrofloxacin) was determined. Amoxicillin-clavulanic acid (Clavamox Pfizer Animal Health) had the highest in-vitro susceptibility against all isolates (96%), all aerobes (94%) and all anaerobes (100%) tested. For gram-negative aerobes, enrofloxacin (Baytril, Bayer Corp.) had the highest in-vitro susceptibility activity. For bacteria associated with treatment of gingivitis, which typically are mixed aerobic/anaerobic and gram-positive/gram-negative organisms, the antimicrobial of choice for clinical use based on these susceptibility tests is amoxicillin-clavulanic acid.

Antimicrobial susceptibility of subgingival bacterial flora in cats with gingivitis.

The aerobic and anaerobic flora from gingival pockets of 40 cats with established gingivitis were cultured. The susceptibility of each isolate to four antimicrobial agents currently approved for use in cats (amoxicillin-clavulanic acid; clindamycin; cefadroxil; enrofloxacin) was determined. Amoxicillin-clavulanic acid (Clavamox) had the highest in-vitro susceptibility against all isolates (92%) and all anaerobes (99% [co-equal with clindamycin]) tested; enrofloxacin (Baytril) had the highest in-vitro susceptibility against all aerobes (90%) tested.

Are we going round in circles, or standing still (and did the Cheshire cat smile enigmatically because of resorptive lesions)?

April 1, 1995. Recent advances and directions in veterinary dentistry are reviewed, to point out that not a lot of progress is being made on some fronts, and none at all on others. The authors conclude that veterinary dentists should brush their own and their pets' teeth at least once during their professional careers.

Wound healing and brain stem auditory evoked potentials after experimental total ear canal ablation with lateral tympanic bulla osteotomy in dogs.

Experimental total ear canal ablation with lateral tympanic bulla osteotomy (TECA-LBO) was performed in 13 normal dogs to evaluate healing and retention of brain stem auditory evoked potentials (BSAEP) after surgery. Healing was evaluated by gross and microscopic examination of the surgery sites after 1 (n = 2), 4 (n = 8), 5 (n = 1), and 6 (n = 1) weeks. One dog was eliminated from the study. Brain stem auditory evoked potentials were measured using an air-conducted sound stimulus before and after surgery and before killing. Two dogs had nearly complete obliteration of the tympanic cavity by immature fibrous connective tissue. Eight dogs responded to surgery by either complete or partial re-formation of the tympanic cavity. Retention of the tympanic membrane in three dogs promoted re-formation of the tympanic cavity and blind epithelialized pockets in the surgery site with accumulation of keratinized debris. Granulation tissue formation and extensive proliferation of new bone on the internal surface of the tympanic bulla was seen in 10 dogs. Proliferative bone completely obliterated the tympanic cavity in two of these dogs. Eleven of 13 dogs had no detectable air-conducted BSAEP after surgery. There was no change in BSAEP measurements before killing compared with postoperative measurements in any dog. Two dogs with retained tympanic membranes had measurable BSAEP after surgery. This study shows that healing after TECA-LBO may be highly variable. Retention of the tympanic membrane and small osteotomies appeared to promote reformation of tympanic cavities and prevent ingrowth of granulation tissue.(ABSTRACT TRUNCATED AT 250 WORDS)

Wound healing and brain stem auditory evoked potentials after experimental ventral tympanic bulla osteotomy in dogs.

Ventral tympanic bulla osteotomy was performed in 13 normal dogs to evaluate healing and retention of brain stem auditory evoked potentials (BSAEP). Healing was evaluated by gross and microscopic examination of the middle ears after 1 (n = 2), 4 (n = 8), 5 (n = 1), and 6 (n = 1) weeks. One dog was eliminated from the study. Brain stem auditory evoked potentials were measured using an air-conducted sound stimulus before and after surgery and before killing. Nine of 12 dogs re-formed the tympanic bulla by formation of fibrous connective tissue lined with cuboidal epithelium in the osteotomy site. Four of the nine dogs had a reduced tympanic bulla volume (estimated 20% to 40% volume reduction) caused by soft tissue ingrowth through the osteotomy. Nine of 12 dogs had proliferation of subperiosteal new bone from the inner surface of the tympanic bulla that varied in severity. Three of these nine dogs had nearly complete obliteration of the tympanic cavity by proliferating subperiosteal new bone. Eight dogs had nodules of granulation tissue containing new bone and mineralization diffusely distributed on the surfaces of the middle ear. The measured BSAEP sensitivity before killing was equivalent to preoperative levels in 11 dogs. The remaining dog had no change in auditory sensitivity after surgery but had a markedly reduced BSAEP detection threshold before killing. This appeared to be attributable to mechanical impingement on the ossicles and tympanic membrane by proliferating bone within the tympanic cavity.(ABSTRACT TRUNCATED AT 250 WORDS)

Jaw lesions resulting from renal hyperparathyroidism in a young dog--a case report.

A five-month-old male Labrador retriever presented with massive bilateral jaw and facial swelling. Ulcers were found on the buccal mucosa and palate, and the jaws were flexible on firm palpation. The dog could eat only soft food and was underweight. Renal hyperparathyroidism was diagnosed based on serum chemistry screen, parathormone concentration, radiological findings and histopathology. The dog was euthanatized because of an extremely poor prognosis.

The history of veterinary dentistry. Part One: From the earliest record to the end of the 18th century.

Dental procedures have been performed on animals, particularly horses, since earliest recorded history. In the absence of anesthesia and an understanding of physiology and pathology, treatment often was unnecessary, inappropriate or barbaric. Progress was made very slowly.

Association of age and body weight with periodontal disease in North American dogs.

Thirteen hundred and fifty dogs were examined under anesthesia at veterinary hospitals in the USA and Canada. Periodontal health was recorded in detail. Teeth were frequently absent (particularly lower third molar, upper and lower first premolars, and incisor teeth). Calculus was most extensive on the upper fourth premolar and molar teeth. Missing teeth, mobility of remaining teeth, extent of calculus and gingival inflammation, and furcation exposure and attachment loss all were more common in small dogs compared with larger dogs, and in order dogs compared with younger dogs.