Assessment of 68 Prosthodontic Crowns in 41 Pet and Working Dogs (2000-2012)

Success of Occlusal Aperture Access for Endodontic Therapy of Canine Teeth in Dogs

The objective of this study was to determine the success of the natural crowns of endodontically treated canine teeth in pet dogs, instrumented and obturated using rotary driven non-taper nickel titanium files, through an occlusal access preparation, without the placement of a prosthetic cast metal crown. A search of medical records at a private veterinary dental referral practice was conducted to identify pet dogs having had endodontic treatment of one or more canine teeth over an eleven-year period (2007-2018). Follow up, performed by the same veterinary dental specialist, included a complete oral health assessment under general anesthesia and included intraoral radiography thereby allowing close visual examination of the crown and restoration as well as assessing endodontic success. Time to follow up was between two and nine years after treatment with a mean of 4.5 years. Analysis revealed that 29/29 (100%) of the treated crowns maintained their stability and did not require extraction. 5/29 (17.2%) of the treated teeth had an enamel fracture requiring additional treatment to the crown after the initial treatment; 1/29 (3.4%) had additional abrasion but did not require treatment and 23/29 (79.3%) were found to have sustained no additional damage. This study supports endodontic treatment without the placement of a prosthetic crown in canine teeth in pet dogs when an occlusal access site is used as described in this paper. Further study is required on the increased risk of fracture of the remaining unaltered canine teeth.

Success of Feather Margin Preparation for Full Metal Prosthodontic Crowns in the Canine Teeth in 84 Pet and Working Dogs (2005-2017)

Medical and dental records of Veterinary Dental Specialties and Oral Surgery were searched to identify dogs that received full metal prosthodontic crowns on canine teeth, using a feather or knife edge preparation between 2005 and 2017. A total of 160 teeth in 84 dogs were included in the study. Current follow-up by telephone, electronic mail, or electronic messaging was conducted, in addition to thorough record review for in-person recheck examinations. Treatment was considered successful if the prosthodontic crown was in place and no further or additional injury to the tooth had occurred at the time of reexamination, owner contact, or patient death. Tooth fracture apical to the prosthodontic crown occurred in 2 (1.25%) cases, bond failure between the tooth and the cement or the cement and the crown occurred in a single case (0.625%), and one metal crown required replacement after 3 years due to wear (0.625%), for an overall failure rate of 2.5%. These results suggest that feather preparation of the margin is at least as, if not more, successful as the more commonly accepted and performed chamfer margin, and thus is a successful, practical and durable option for prosthodontic crown treatment in dog canine teeth.

Retrospective Study of 18 Titanium Alloy Crowns Produced by Computer-Aided Design and Manufacturing in Dogs

Computer-aided design (CAD) and computer-aided manufacturing (CAM) technology is routinely used in various fields of human dentistry, particularly prosthodontics. Reverse engineering and additive manufacturing allow the technician to create an easier, faster and more accurate restoration, with a natural design and adequate strength. Eighteen titanium alloy full crowns were produced for canine teeth of 7 working dogs using CAD/CAM technology (3D BioCare, Nobel Biocare). Reasons for crown therapy included abrasion, enamel infraction, and crown fracture. Crown preparation was routinely performed, and impressions were delivered to the laboratory where digital impressions were performed with a lab scanner. Using 3D dental design software, the metal crown was designed and sent for manufacture. Each prosthodontic crown was then carved from a solid titanium alloy block to obtain the final crown. All prosthodontic crowns were an adequate fit, and cementation was routinely performed. Crowns were lost from 2 canine teeth during the dogs' normal working activity, in one case, for 2 times. In all cases, replicas were requested. In the first case, the second cementation was successful. In the second case, the second crown was again lost and only the third cementation was successful. Follow up of all cases range from 12 to 62 months. Mean survival time for the crowns was 58.0 months. Here, CAD/CAM technology is shown to be a useful tool for manufacturing accurate prosthodontic crowns for veterinary patients. Moreover, CAD/CAM enables the production of prosthodontic crown replicas in a very short time and at relatively low cost compared to traditional methods, consequently eliminating the need for at least one anesthetic procedure in the incidence of crown cementation failure.

Cementation of Full Coverage Metal Crowns in Dogs

This step-by-step article describes the technique for cementation of a full metal prosthodontic crown on the maxillary fourth premolar tooth of a dog using a common resin-based cement.

The Influence of Axial Grooves on Dislodgment Resistance of Prosthetic Metal Crowns in Maxillary Fourth Premolar Teeth of Dogs

The reported failure rate for full veneer crowns in dogs is suboptimal, particularly in teeth with naturally poor retentive features such as the maxillary fourth premolar tooth of dogs. Although the data regarding crown retention on the maxillary fourth premolar in dogs are limited, there are data that suggest the crown failure rate could be similar to that of the canine tooth. Thus, methods to improve retentive features of the preparation design should be pursued. The objective of the present study is to quantify the influence of axial grooves on the dislodgment resistance of full veneer metal crowns in dogs. Crown dislodgment testing was performed on cast alloy dies of the maxillary fourth premolar tooth with unfavorable retentive features prepared with and without axial grooves, to quantify the difference in force required to dislodge a cemented full veneer crown. The force required to cause crown dislodgment was recorded for each crown. Statistical analysis revealed a significant increase ( P < .001) in the force required for crown dislodgment in teeth prepared with axial grooves compared to those prepared without axial grooves.