Mechanical and electrothermal debonding: effect on ceramic veneers and dental pulp.

This study compared the ability of three orthodontic debonding techniques for the removal of brackets from ceramic veneers without creating veneer damage. Three experimental groups included metal brackets debonded by either Howe pliers, lift off debonding instrument (LODI, 3M Unitek), or electrothermal debonder (ETD, "A" Company), as well as a group of electrothermally debonded ceramic brackets. It also evaluated and compared the intrapulpal temperature changes produced by electrothermal debonding metal and ceramic brackets. A sample of 95 extracted maxillary first premolars were prepared and restored with Mirage ceramic veneers (Chameleon Dental Products, Inc.). Veneer buccal surfaces were treated with 2.5% hydrofluoric acid, before silane application and bracket bonding with a no-mix resin. Specimens were thermocycled before debonding. All debonded specimens were examined under x20 magnification for veneer damage. A thermocouple was positioned at the pulp chamber buccal wall to record temperature increases (due to ETD activation) through a digital thermometer. Results suggest that ETD provides predictable debonding to ceramic brackets with no veneer damage and minimal risk to the pulp. Removal of metal brackets through electrothermal debonding produced ceramic damage in 13% of cases, and elevated temperatures beyond the threshold of irreversible pulpal damage (5.5 degrees C) in 46% of cases. Howe plier and LODI bracket removal are associated with ceramic damage incidence of 21% and 35%, respectively.

Dental injuries at the 1989 Canada games: an epidemiological study.

The management and prevention of dental trauma is an integral part of the medical services provided at major athletic events. This paper reviews the organization and delivery of the dental services provided at the 1989 Canada Games. The nature, incidence and management of the dental problems reported in the participant population of 3,411 athletes are also described. During the two-week competition, 15 participants were assessed and treated for various dental conditions, including hard- and soft-tissue injury of the oral cavity, and temporomandibular joint sprain. The sports with the highest incidence of dental injury for the male population were wrestling (one per cent) and basketball (0.8 per cent). For the female population, these sports were basketball (2.5 per cent) and field hockey (1.3 per cent). The dental services provided during the games included emergency assessment and treatment, fabrication of mouthguards, and in-service education to medical team members.

Protective mouthguards and sports injuries.

In summary the advantages of providing custom-fitted mouthguards for athletes, especially those involved in contact sports, has been discussed along with the methodology of construction. Because of the apparent lack of negative effects on physical performance and the superior protective characteristics of custom-fitted mouthguards, it seems logical to recommend their use in the competitive sports arena.

Bacteraemia and tissue damage resulting from air polishing.

This study investigates the production of bacteraemia in dental prophylaxis by use of a commercially available air polishing device. Prophylaxis by means of the conventional rubber cup and paste method was used as a control. The study showed that air polishing can result in loss of epithelium at the gingival margin. The likelihood of a bacteraemia resulting from air polishing, in the absence of gingivitis, was less than in the group undergoing conventional prophylaxis. Although a higher number of bacteraemias was seen in the control group, the difference between the two groups was not statistically significant. Results indicate that patients who are at risk continue to require antibiotic cover.