Furcation anatomy of the first mandibular molar in dogs.

Tooth surface and interradicular area (furcation) measurements were taken of 20 first mandibular molar teeth obtained randomly from canine cadavers. The lingual furcation entrance had a mean width of 1.2 +/- 0.3 mm. The buccal furcation entrance had a mean width of 1.3 +/- 0.4 mm. There was no significant difference between mean furcation entrance measurements. The horizontal attachment area between the cementoenamel junction and the coronal roof of the lingual furcation was 1.1 +/- 0.4 mm. The horizontal attachment area between the cementoenamel junction and the coronal roof of the buccal furcation (0.5 +/- 0.3 mm) was significantly different from the lingual horizontal attachment area. Distal root length and mesial root length were 16.0 +/- 1.5 mm and 16.1 +/- 1.6 mm, respectively. The mean coefficient of variation for variables measured was 14.0%. Tooth size did not have a significant effect on furcation entrance measurement. All teeth had a concavity coronal to the furcation area, which extended apically for a mean distance of 65.6% of the distal root length and 83.8% of the mesial root length. Furcation anatomy of the first mandibular molar is complex and may be a contributing factor in periodontal disease involving the interradicular area.     

Potential attachment area of the first mandibular molar in dogs.

Tooth root and root trunk surface area measurements were taken from 20 first mandibular molar (M1) teeth obtained randomly from canine cadaver specimens. The mean root surface area for all teeth was 497.1 +/- 116.2 mm2. The cumulative surface areas of the mesial (MR) and distal (DR) roots were 251.4 +/- 70.2 mm2 and 211.7 +/- 51.9 mm2, respectively. The root trunk surface area was 34.0 +/- 21.4 mm2. Surface area measurements for individual roots and the root trunk were significantly different. Cumulative individual root surface area (MR + DR) was 93.2% of total root surface area. The MR surface area contributed most to total root surface area (50.6%) and cumulative individual root surface area (54.3%). The mean distance from the beginning of the root trunk to the furcation was 2.1 mm. On the basis of the linear variation of the percentage of root surface area of the M1, 44.6% of the total root surface area was 3 to 7 mm apical to the most coronal aspect of the cementoenamel junction. The MR was heart-shaped, compared with the more cylindrical shape of the DR.     

Dental implant replacement of the mandibular first molar tooth in a dog

A new dental implant system was used to replace the mandibular right first molar tooth in an eleven-month-old male/intact, utility trained German shepherd dog. The permanent mandibular right first molar tooth had been extracted as treatment for an extensive carious lesion when the dog was 9-months of age. There were no complications associated with placement of the dental implant. However, peri-implant osteomyelitis occurred secondary to a traumatic oral wound 6-months following implant placement. The 17-month post-operative examination indicated that the implant system used in this case could be maintained in a working dog that uses extreme bite forces. However, periodontal inflammation and vertical bone loss exposing the implant fixtures were noted during oral examination. Further clinical applications are required to determine if the periodontal inflammation and vertical bone loss noted in this case were complications associated with the implant, maturity of bone at the time of implant fixture placement, general biting/chewing forces placed on carnassial teeth, or the oral trauma that occurred 6-months following implant placement.     

Endodontic disease of the mandibular first molar tooth secondary to caudal crossbite in a young Shetland sheepdog

A six month-old intact female Shetland sheepdog was referred to the University of Illinois Veterinary Dental Clinic with a left-sided mandibular deviation and a thickened left ventral mandible in the region of the first molar tooth. On oral examination, left caudal crossbite was diagnosed. Dental radiographs revealed endodontic disease of the mandibular first molar tooth involved in the crossbite. Because of the difficulty of treating caudal crossbite and the potential of a pathological mandibular fracture, the endodontically affected tooth was extracted. Ten months following the extraction, mandibular deviation and alveolar bone lysis were resolved, but alveolar ridge resorption was present. The abnormal occlusal relationship caused by the caudal crossbite may have led to movement of the tooth, resorption of the tooth alveolus, and irreversible pulpal damage. Although not employed in this case, use of alveolar ridge preservation techniques can prevent mandibular bone loss after extractions.     

Morphologic features of the root canal system of the maxillary fourth premolar and the mandibular first molar in dogs

Root canal morphology was evaluated in 72 maxillary fourth premolar and 59 mandibular first molar teeth. An apical delta was present in all roots (n = 334). The apical delta represented approximately 12-18% of the total root length for all roots. Non-apical ramifications from the main canal were observed in 25.1% of roots. Secondary canal(s) were present in 20.6% of roots, while lateral canal(s) were present in 6.9% of roots. The distal root of the maxillary fourth premolar had the highest incidence (47.2%) of non-apical ramifications. Overall, 68.0 and 20.4% of maxillary fourth premolar and mandibular first molar teeth had non-apical ramifications, respectively. The prevalence and location of non-apical ramifications may influence clinical decision making when performing endodontic therapy.     

Relationship of body measurements and body condition score to body weight in modern Finnish Ayrshire cows

Abstract

The differences in body weight (BW) and measurements between the cows of today and the early 70s was evaluated and the usefulness of heart girth (HG), wither height, body length (BL) and body condition score (BCS) as predictors of the BW of modern Finnish Ayrshire cows was estimated. During the last three decades, the BW, HG and BL has increased indicating change in body conformation. The BW prediction equation based on early 70s data underestimate the BW of modern Ayrshire cows. Based on current data it is recommended to use different models to predict BW for primiparous and multiparous cows. From single measurements, HG predicted BW most accurately. Inclusion of BL in model gave slight improve in BW prediction, especially for primiparous cows. An additional term of age or days in milk (DIM) for primiparous cows and BCS or DIM for multiparous cows along with HG increased slightly the accuracy of BW prediction.     

Odontoclastic resorptive lesion of a mandibular right first molar in a cougar

A two-year old neuteral/male cougar (Felis concolor) was presented because of abnormal eating habits and an irregularity of the mandibular right first molar that was noted by the caretaker. Oral examination and dental radiographs showed a lesion consistent with odontoclastic resorption of the mandibular right first molar, and a crown fracture and dilacerated root of the maxillary right first incisor. Exodontic therapy was performed on both teeth. The caretaker reported no problems associated with the patient's oral cavity 10-months following treatment.     

Treatment of mandibular first molar teeth with endodontic-periodontal lesions in a dog

A two-year-old spayed/female Miniature Pinscher was treated for mobility of the left and right mandibular first molar teeth. Periodontal probing and intraoral dental radiographs indicated severe periodontal attachment loss. It was determined that both teeth had endodontic-periodontal lesions based on restoration of periodontal attachment and partial resolution of radiolucent periapical lesions following treatment which emphasized endodontic therapy.     

Prediction of body weight from body measurements in grass cutters

In order to predict the body weight of grass cutters from linear body measurements, the weights and measurements of 50 intensively managed female grass cutters aged 5 months were fitted into linear, quadratic and cubic regression models. Highly significant (p?<?0.01) R ² values ranging from 74 to 98 % were obtained indicating that all body measurements were good predictors of body weight. Although quadratic and cubic models gave slightly higher R ² values than linear models, it is recommended that farmers should use a simple linear equation based on tail length or heart girth to predict the body weight of their grass cutters. The recommended equations are (weight in kg)?=?0.47?+?0.08 (tail length in cm) and (weight in kg)?=?0.32?+?0.07 (heart girth in cm).     

Comparison of radiographic and anatomic femoral varus angle measurements in normal dogs

Objective— To determine if the clinically practiced method of radiographic femoral varus angle (R-FVA) measurement is repeatable, reproducible, and accurate.
Study Design— Radiographic and anatomic study.
Animals/Sample Population— Normal Walker hound cadavers (n=5) and femora (n=10).
Methods— Cadavers were held in dorsally-recumbent and torso-elevated positions as 3 craniocaudal radiographs were made of each femur, by each of 2 different technicians. Femora were then harvested for direct measurement of anatomic femoral varus angle (A-FVA). R-FVA was measured on each radiograph by each of 3 examiners on 3 separate occasions. Intra-observer (repeatability) and inter-observer (reproducibility) variance in R-FVA measurement and the strength of relationship between R-FVA and A-FVA (accuracy) were determined.
Results— Mean (±SD) A-FVA was 5.2±2.1° (range, 2.4–8.2°). Mean (±SD) R-FVA was 5.8±1.0° (range, 2.7–9.6°). Intra-observer variance (range: 11–16%) and inter-observer variance (16%) were acceptable. The strength of relationship between measured R-FVA and A-FVA (maximum adjusted R²<0) was unacceptably low regardless of observer, patient position, or radiographic technician.
Conclusion— R-FVA measurement was repeatable and reproducible, but not statistically accurate in predicting A-FVA in these 5 normal Walker hounds. The detected inaccuracy may be real or the result of a selection bias for normal dogs obscuring the true relationship.
Clinical Relevance— R-FVA may not be an accurate method of femoral varus measurement in dogs with A-FVA<10°. Using Slocum's criteria for distal femoral osteotomy (R-FVA>10°), the procedure would not have been erroneously performed in any of the normal dogs of this study.     

Furcation canals of the maxillary fourth premolar and the mandibular first molar teeth in cats

The furcation region morphology was evaluated in 103 mature feline carnassial teeth (54 maxillary fourth premolar and 49 mandibular first molar teeth). Patent furcation canals were present in 27.2% of teeth. No significant difference (p = 0.88) in distribution of this anatomical variation was found between maxillary fourth premolar and mandibular first molar teeth. The mean width of these furcation canals was 104.0 microns with two-thirds of the canals having a buccal orientation. The presence of furcation canals could be a factor in the etiopathogenesis of feline dental resorptive lesions, as well as a characteristic to be considered in the diagnosis, prognosis, and treatment of endodontic or periodontic-endodontic lesions in cat teeth.     

Association of body weight and body condition with survival in dogs with heart failure

BACKGROUND: Obesity is a risk factor for cardiovascular disease in people, but overweight and obese human heart failure patients have improved survival compared with normal--or underweight controls--the obesity paradox. The purpose of this study was to determine if there is an association of body weight and body condition with survival in dogs with heart failure. HYPOTHESIS: That body condition and changes in body weight are predictors of survival in dogs with heart failure. ANIMALS: One hundred and eight dogs with heart failure (International Small Animal Cardiac Health Council stages 2, 3a, or 3b) secondary to dilated cardiomyopathy or chronic valvular disease. METHODS: Medical records were reviewed, and data regarding initial body weight and body condition score (BCS), subsequent changes in body weight, and treatment were collected. Survival times were determined for dogs that were discharged from the hospital and lived >24 hours. RESULTS: Survival was significantly different between dogs that gained, lost, or maintained body weight over the course of their disease (P= .04), with dogs that gained weight surviving the longest. BCS and medications were not significantly associated with survival time; however, n-3 fatty acid intake was associated with longer survival time (P= .009). CONCLUSIONS AND CLINICAL IMPORTANCE: These results suggest that changes in body weight might be an important consideration in the survival of dogs with heart failure.     

Use of radiographic measurements in the evaluation of dogs with medial patellar luxation

This prospective study used radiographic techniques to evaluate the inclination, Norberg, quadriceps and femoral varus angles, and the patellar position in dogs with developmental medial patellar luxation. The study also compared these measurements pre- and post-operatively to determine how they were affected by surgical procedures. Eighteen dogs with unilateral or bilateral luxation were used, and 4 groups were established according to luxation grade. Except for the quadriceps angle, there was no difference among the groups preoperatively. Significant differences for the quadriceps angle were observed between Grades 1 and 3, and between Grades 2 and 3. The Norberg and femoral varus angles and the patellar position showed no changes between pre- and postoperative groups. However, measurements of the preoperative quadriceps angle and postoperative inclination angle may be useful for evaluating dogs with grade-3 luxation. Further studies using other imaging techniques are required in dogs with severe grade-4 luxation due to the difficulty in obtaining a good radiographic position.