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.

Evaluation of a model for induction of periodontal disease in dogs / Avaliação de um modelo para indução de doença periodontal em cães

There are several methods for inducing periodontal disease in animal models, being the bone defect one of the most reported. This study aimed to evaluate this model, through clinical, radiographic, tomographic and histological analyzes, thus providing standardized data for future regenerative works. Twelve dogs were subjected to the induction protocol. In a first surgical procedure, a mucoperiosteal flap was made on the buccal aspect of the right third and fourth premolars and a defect was produced exposing the furcation and mesial and distal roots, with dimensions: 5mm coronoapical, 5mm mesiodistal, and 3mm buccolingual. Periodontal ligament and cementum were curetted and the defect was filled with molding polyester, which was removed after 21 days on new surgical procedure. Clinical and radiographic examinations were performed after the two surgeries and before the collection of parts for dental tomography and histological analysis. All animals showed grade II furcation exposure in both teeth. Clinical attachment level increased after induction. Defect size did not change for coronoapical and buccolingual measurements, while mesiodistal size was significantly higher than at the time of defect production. Radiographic analysis showed decreased radiopacity and discontinuity of lamina dura in every tooth in the furcation area. The horizontal progression of the disease was evident in micro-computed tomography and defect content in the histological analysis. Therefore, it is concluded that this method promotes the induction of periodontal disease in dogs in a standardized way, thus being a good model for future work.

Existem vários métodos para indução de doença periodontal em modelos animais, sendo o do defeito ósseo um dos mais descritos. Este estudo objetiva avaliar esse modelo em cães, por análises clínica, radiográfica, tomográfica e histológica, fornecendo assim dados padronizados para trabalhos futuros. Doze cães foram submetidos ao protocolo de indução. Em um primeiro procedimento cirúrgico, um retalho mucoperiosteal foi produzido na face vestibular do terceiro e do quarto dentes pré-molares direitos e foi criado um defeito, expondo a furca e parte das raízes mesial e distal, com as dimensões: 5 mm corono-apical, 5 mm mesio-distal e 3 mm vestíbulo-lingual. O ligamento periodontal e o cemento foram curetados e o defeito foi então preenchido com poliéster de moldagem, que foi removido após 21 dias em um novo procedimento cirúrgico. Exames clínicos e radiográficos foram realizados após as duas cirurgias e antes da coleta dos dentes e tecidos associados para análise tomográfica e histológica. Todos os animais apresentaram exposição de furca grau II em ambos os dentes. O nível clínico de inserção aumentou após a indução. O tamanho do defeito não apresentou alteração nas medidas corono-apical e vestíbulo-lingual, enquanto o tamanho mesio-distal foi significativamente maior que o produzido. Análise radiográfica mostrou diminuição da radiopacidade e descontinuidade da lamina dura na região da furca dos dois dentes. A progressão horizontal da doença foi evidente na microtomografia e pelo conteúdo do defeito nas análises histológicas. Assim, conclui-se que este modelo promove a indução de doença periodontal em cães de forma padronizada, sendo um bom modelo para trabalhos futuros.

Naturally occurring periodontal bone loss in the wild deer mouse, genus Peromyscus.

BACKGROUND: Historically, animal models for the study of periodontal diseases have incorporated surgically created defects, plaque retentive ligatures, as well as soft and high-sucrose diets which may not accurately reflect progression of the natural disease. Spontaneous periodontal disease is seen in a few animal species, but these are often expensive to maintain and are unsuitable for manipulation using advanced molecular biology techniques. Mice are inexpensive, easy to maintain, and are routinely used for transgenic experiments and are therefore an optimal animal for research purposes. However, it is commonly accepted that mice do not spontaneously develop periodontal disease. The purpose of this study was to determine if a mouse population that exhibits periodontal breakdown in the wild could be found, allowing for genetic manipulation of naturally occurring periodontal disease. METHODS: We examined over 2,500 dry skulls of several Peromyscus species from various locations and habitats on the west coast of North America for periodontal bone loss in the molars, using furcation involvement as an indicator of disease severity. Alveolar bone loss was classified as Grade I) horizontal component of bone loss in the furcations; II) through-and-through furcations; and III) through-and-through furcations with alveolar bone loss into the apical third of the root. RESULTS: The proportions of individual mice experiencing bone loss were 3.8% for Class I-III involvement, 1.3% for Class II-III involvement, and 0.5% for Class III alone. Three subspecies of P. keeni and one subspecies of P. maniculatus had periodontal disease prevalences in 7% to 13.5% of their samples. Mice from isolated islands had 1.8- to 4.7-fold higher disease prevalence than those located on the mainland, with even greater prevalence on small islands. No statistically significant differences between genders were found. CONCLUSIONS: It appears that periodontal disease is far more common in this mouse genus than previously believed. Some of the subspecies demonstrated severe periodontal disease at a prevalence comparable to that found in humans.

Reparaçäo de defeitos de furca classe II tratados por RTG: análise histológica em plano vestíbulo-lingual, em cäes / Class II furcation defects treated by GTR: histological analysis of buccal-lingual sections in dogs

Este trabalho teve por objetivos o estudo do comportamento do tecido epitelial e a formaçäo de um novo sulco gengival após procedimento de RTG em defeitos de furca classe II criados cirurgicamente, em cäes. A análise histológica foi realizada em plano vestíbulo-lingual e foi possível, também, descrever o tecido neoformado no interior destes defeitos. Foram usados 4 cäes, sem raça definida, nos quais foram criados defeitos nos P3, P4 e M1 mandibulares, procurando reproduzir defeitos de furca classe II. Estes defeitos foram tratados por técnica de RTG, com membranas näo reabsorvíveis (PTFE-e). As membranas colocadas, permaneceram em posiçäo por quatro semanas, quando foram removidas. A partir da remoçäo das membranas, o sacrifício dos animais foi programado para a obtençäo de espécimes correspondentes a 7 e 28 dias de reparaçäo. O pós-operatório foi sem intercorrências e, no momento da remoçäo das membranas, foi observado o completo preenchimento das bifurcaçöes, por tecido neoformado, em todos os espécimes...

Periodontal healing of canine experimental grade-III furcation defects treated with autologous fibrinogen and absorbable barrier membrane.

OBJECTIVE: To determine the effects of autologous fibrinogen (AF) and absorbable barrier membrane (ABM) on periodontal healing of canine experimental grade-III furcation defects. ANIMALS: 18 conditioned, laboratory-source, adult Beagles. PROCEDURE: Defects were developed bilaterally at the second and fourth premolars and maintained for 12 weeks. Defects were treated with AF, ABM, AF and ABM, or debridement. Digital subtraction radiography, histologic evaluation, and histomorphometric analysis of defect healing was done at 1, 3, and 6 months after treatment to determine percentage increases in bone volume, height, area, and length of periodontal regeneration along the perimeter of the defect. RESULTS: Comparison of defects at post-treatment intervals indicated significantly greater healing of debridement and AF-treated defects, compared with ABM-treated defects at 3 months; however, by 6 months, there were no significant differences in defect healing for all histomorphometric variables. Defects treated with ABM were associated with significantly less root ankylosis than other treatments. Defects treated with debridement had significantly greater increases in bone volume at 6 months after treatment, compared with groups treated with ABM. There was a significant correlation between regenerated bone area, bone volume, and periodontal regeneration for all treatments at 3 and 6 months after treatment. CONCLUSION AND CLINICAL RELEVANCE: Use of AF and ABM did not enhance the amount of periodontal healing, compared with debridement only. The ABM-treated defects were essentially devoid of root ankylosis. Grade-III furcation defects may respond equally well to conservative periodontal surgery or guided tissue regenerative techniques. The prevention of root ankylosis is a substantial benefit favoring this latter method of treatment.

Oral malodor in beagles: association with indicators of periodontal disease.

The study of oral malodor continues to receive attention. Most bad breath is of oral origin and can be corrected with proper oral hygiene. Studies performed with saliva from people with periodontal disease and from healthy individuals showed that saliva from diseased patients produced a more objectionable odor faster than that of healthy people, and that the volatile sulfur components (VSC) produced may actually play a role in the etiology of periodontal disease. However, not all people or animals with bad breath have periodontal disease. The objectives of this study were to determine if a trained panel could discriminate between 10 dogs with clinically defined periodontal disease and those with relatively healthy periodontium. Second, this study attempted to establish a correlation between odor intensity and six clinical parameters of oral health. The judges were able to differentiate between the two groups of dogs based only on oral malodor (p < 0.02). There were strong associations of the intensity of oral malodor with oral health index scores. The correlations established between odor and gingivitis (r = 0.81) and between odor and furcation exposure (r = 0.88) were very high and statistically significant. Similarly, probing depth (r = 0.73), plaque (r = 0.07) and tooth mobility (r = 0.66) showed clear, positive relationships with oral malodor.

Endodontic therapy and management of grade II furcation periodontal disease in a mandibular first molar tooth of a dog.

Conventional endodontic therapy, necessitated by the development of a carious lesion coronal to the furcation area of a mandibular first molar tooth, and management by gingivoplasty of a resultant Grade II furcation lesion are described. In addition, the significance of radiographic changes associated with the periapical region of an undercondensed mesial root is addressed.

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.