Intra-pulp temperature increase of equine cheek teeth during treatment with motorized grinding systems: influence of grinding head position and rotational speed.

BACKGROUND: In equine practice, teeth corrections by means of motorized grinding systems are standard procedure. The heat resulting from that treatment may cause irreparable damage to the dental pulp. It has been shown that a 5.5°C temperature rise may cause severe destruction in pulp cells. Hence, the capability to continuously form secondary dentine is lost, and may lead, due to equine-typical occlusal tooth abrasion, to an opening of the pulp cavity.To obtain reliable data on the intra-pulp increase in temperature during corrective treatments, equine cheek teeth (CT) were modified in a way (occlusal surface smoothed, apical parts detached, pulp horns standardized) that had been qualified in own former published studies. All parameters influencing the grinding process were standardized (force applied, initial temperatures, dimensions of pulp horns, positioning of grinding disk, rotational speed). During grinding experiments, imitating real dental treatments, the time span for an intra-pulp temperature increase of 5.5°C was determined. RESULTS: The minimum time recorded for an intra-pulp temperature increase of 5.5°C was 38 s in mandibular CT (buccal grinding, 12,000 rpm) and 70 s in maxillary CT (flat occlusal grinding, 12,000 rpm). The data obtained showed that doubling the rotational speed of the disk results in halving the time span after which the critical intra-pulp temperature increase in maxillary CT is reached. For mandibular CT, the time span even drops by two thirds. CONCLUSION: The use of standardized hypsodont CT enabled comparative studies of intra-pulp heating during the grinding of occlusal tooth surfaces using different tools and techniques. The anatomical structure of the natural vital hypsodont tooth must be kept in mind, so that the findings of this study do not create a deceptive sense of security with regard to the time-dependent heating of the native pulp.

Oral and dental imaging equipment and techniques for small animals.

In the diagnosis and treatment of oral and dental diseases in dogs and cats, digital intraoral radiography offers many advantages over the use of standard dental radiographic film, including rapid image generation, easier exposure correction, enhancement, and paperless storage. Digital image receptors can be divided into 2 main types, direct digital systems using charged coupled devices and complementary metal oxide semiconductor sensors, and indirect digital systems using phosphor plates with a computerized scanner. Each system is paired with a computer software system to allow handling, visualization, enhancement, sharing, and archiving of the images.

Equipment for oral surgery in small animals.

This article provides an overview of equipment used for oral surgery. Specific instruments and materials used when performing relevant operative procedures are also mentioned in other articles in this issue.

Pulpar temperature changes during mechanical reduction of equine cheek teeth: comparison of different motorised dental instruments, duration of treatments and use of water cooling.

REASONS FOR PERFORMING STUDY: Although equine motorised dental instruments are widely used, there is limited information on their thermal effect on teeth. The recently described variation in subocclusal secondary dentine depth overlying individual pulp horns may affect heat transmission to the underlying pulps. OBJECTIVES: This study compared the effect of 3 different equine motorised dental instruments on the pulpar temperature of equine cheek teeth with and without the use of water cooling. It also evaluated the effect of subocclusal secondary dentine thickness on pulpar temperature changes. METHODS: A thermocouple probe was inserted into the pulp horns of 188 transversely sectioned maxillary cheek teeth with its tip lying subocclusally. Pulpar temperature changes were recorded during and following the continuous use of 3 different equine motorised dental instruments (A, B and C) for sequential time periods, with and without the use of water cooling. RESULTS: Using motorised dental instrument B compared with either A or C increased the likelihood that the critical temperature was reached in pulps by 8.6 times. Compared with rasping for 30 s, rasping for 45, 60 and 90 s increased the likelihood that the critical temperature would be reached in pulps by 7.3, 8.9 and 24.7 times, respectively. Thicker subocclusal secondary dentine (odds ratio [OR] = 0.75/mm) and water cooling (OR = 0.14) were both protective against the likelihood of the pulp reaching the critical temperature. CONCLUSIONS: Prolonged rasping with motorised dental instruments increased the likelihood that a pulp would be heated above the critical temperature. Increased dentinal thickness and water cooling had protective roles in reducing pulpar heating. POTENTIAL RELEVANCE: Motorised dental instruments have the potential to seriously damage equine pulp if used inappropriately. Higher speed motorised dental instruments should be used for less time and teeth should be water cooled during or immediately after instrument use to reduce the risk of thermal pulpar damage.

[Veterinary dentistry: an update 2008]. / Tandheelkunde bij dieren: een update 2008.

Rooted in human dentistry, veterinary dentistry has developed steadily in the Netherlands since the 1980s and is now recognized as an essential discipline of veterinary medicine. The availability of specialized tools and techniques has led to improved treatment outcomes and results, with the choice of treatment being largely determined by the functionality of the dentition and the costs involved. Domestic animals and horses with dental problems should be referred to dental veterinarians. The Working Group Veterinary Dentistry in the Netherlands is an association for skilled veterinarians with professional dental equipment at their disposal.

[Renaissance of equine dentistery, an abandoned discipline, which one tries to recover]. / La renaissance de la dentisterie équine, une discipline délaissée, que l'on essaye de reconquérir.

The author illustrates by the study of ancient texts the interest shown for equine dentistry since the age of times. The first detailed studies on the technique go back to the 17th century. The 19th and the beginning of the 20th centuries were fertile in instrumental as well as technical discoveries; it was the time of creativity, and he quotes authors like Günther father and son, Frick, Goubaux and Barrier, Mérllat, Cadiot, and Colyer with his enormous work on animal dentistry published in 1936. During and right after the 2nd World War, it is the time of desertion, with only one exception, Erwin Becker, who out of Berlin gives an extraordinary prestige to the dentistry. The beginning of the revival seems to go back to 1975-1980. At this point of time, non veterinarian "dentists" breach in, the moust famous being Dale Jeffrey, who opens a school, creates an academy and publishes a newspaper. The author reviews all the existing teaching method. A new professions is born, the dental technician, one hurdle remains how to integrate it within the world of the veterinarians? The author presents the British example, the best regulated. He also shows how the French National Veterinary Schools have restored the teaching of dentistry. The author regrets that the Medias glorify the dental technicians under the pompous and improper trade name "equine dentists", to the detriment of the veterinarians.

Management of generalized gingival enlargement in a dog--case report and literature review.

The present report describes treatment of a dog with generalized gingival enlargement and serves as a review of etiology and treatment options for this condition. The combined use of scalpel blade, electrosurgical equipment, and a 12-fluted bur on a high-speed handpiece with water irrigation allowed for accurate excision of excess gingival tissue and contouring of remaining gingiva. Surgery coupled with professional dental cleaning/periodontal therapy can decrease the recurrence of this condition. In addition, home oral hygiene is an important component of the treatment plan. The history of patients with gingival enlargement should be reviewed carefully, including drug history and previous medical conditions, in an attempt to elucidate a specific cause and thus allow for greater long-term success.

Temperature changes in dental pulp associated with use of power grinding equipment on equine teeth.

OBJECTIVE: To quantify the temperature changes in the dental pulp associated with equine dental procedures using power grinding equipment. DESIGN: A matrix experimental design with replication on the same sample was followed to allow the following independent variables to be assessed: horse age (young or old), tooth type (premolar or molar), powered grinding instrument (rotating disc or die grinder), grinding time (15 or 20 seconds) and the presence or absence of water coolant. PROCEDURE: Sound premolar and molar teeth from a 6-year-old horse and a 15-year-old horse, which had been removed postmortem, were sectioned parallel to the occlusal plane to allow placement of a miniature thermocouple at the level of the dental pulp. The maximum temperature increase, the time taken to reach this maximum and the cooling time were measured (n=10 in each study). The teeth were placed in a vice and the instrument used on the tooth as per clinical situation. RESULTS: Significant differences were recorded for horse age (P < 0.001), instrument type (P < 0.001), grinding time (P < 0.001) and presence or absence of coolant (P < 0.001). There was no significant difference for tooth type. CONCLUSION: Thermal insult to the dental pulp from the use of power instruments poses a significant risk to the tooth. This risk can be reduced or eliminated by appropriate selection of treatment time and by the use of water irrigation as a coolant. The increased dentine thickness in older horses appears to mitigate against thermal injury from frictional heat.

In vitro study of heat production during power reduction of equine mandibular teeth.

OBJECTIVE: To measure the amount of heat generated during 3 methods of equine dental reduction with power instruments. DESIGN: In vitro study. SAMPLE POPULATION: 30 premolar and molar teeth removed from mandibles of 8 equine heads collected at an abbatoir. PROCEDURE: 38-gauge copper-constantan thermocouples were inserted into the lingual side of each tooth 15 mm (proximal) and 25 mm (distal) from the occlusal surface, at a depth of 5 mm, which placed the tip close to the pulp chamber. Group-NC1 (n = 10) teeth were ground for 1 minute without coolant, group-NC2 (10) teeth were ground for 2 minutes without coolant, and group-C2 (10) teeth were ground for 2 minutes with water for coolant. RESULTS: Mean temperature increase was 1.2 degrees C at the distal thermocouple and 6.6 degrees C at the proximal thermocouple for group-NC1 teeth, 4.1 degrees C at the distal thermocouple and 24.3 degrees C at the proximal thermocouple for group-NC2 teeth, and 0.8 degrees C at the distal thermocouple and -0.1 degrees C at the proximal thermocouple for group-C2 teeth. CONCLUSIONS AND CLINICAL RELEVANCE: In general, an increase of 5 degrees C in human teeth is considered the maximum increase before there is permanent damage to tooth pulp. In group-NC2 teeth, temperature increased above this limit by several degrees, whereas in group-C2 teeth, there was little or no temperature increase. Our results suggest that major reduction of equine teeth by use of power instruments causes thermal changes that may cause irreversible pulp damage unless water cooling is used.

The effect of three types of rasps on the occlusal surface of equine cheek teeth: a scanning electron microscopic study.

Two hand rasps (tungsten chip blade, solid carbide blade) and an electrically-driven solid carbide axial bur were used to treat the cheek teeth of 2 horses immediately postmortem. All teeth were normal and were rasped to a standard considered satisfactory in practice. Six teeth from each horse served as untreated controls. Following treatment, the teeth were extracted and the clinical crown removed and prepared for scanning electron microscopy. Teeth were also extracted and examined from a horse that had excessive dental treatment previously. Dental debris created by the procedures was collected and examined. All three rasp techniques resulted in amputation of odontoblast processes. The solid carbide blade cut deep gouges and grooves into the surface of the dentin, chipping the enamel and peripheral cement. No smear layer was created. Rasping with a tungsten chip blade created a partial smear layer and a smoother surface than the solid carbide blade. The electrically-driven bur produced a complete smear layer and removed all dental tissues to a smooth layer. The enamel had also been damaged by the electric bur. Crown particles collected after the procedures were larger following hand rasping compared with particles produced by the electric bur. The extent of damage to sensitive and vital dentin tissue was of concern. Further studies are required to establish the optimum technique for rasping equine cheek teeth.

[The sharpening and polishing of dental instruments]. / Het slijpen van het tandheelkundige handinstrumentarium.

This article describes the maintenance of dental instruments in a companion animal practice, in particular the correct sharpening techniques for tartar scrapers, curettes, excavators, and elevators. Sharp instruments are essential for the quality and speed of dental care.