Efectos de los destartaradores de ultrasonidos sobre la vitalidad pulpar en los dientes del perro. Estudio Experimental

Abstract

Se plantea el estudio de las posibles lesiones pulpares inducidas por ultrasonidos de 29 KHz, que son los utilizados en la clínica.

Se utilizaron 84 premolares, a los que se aplicaron los ultrasonidos durante 30, 60 y 90 segundos, a la par que se tomaba la temperatura de la pulpa dental, para ver su hipotético incremento.

Además de las valoraciones cualitativas de las variaciones de temperatura, se realizaron estudios macroscópicos e histológicos para determinar la presencia de posibles lesiones (Pulpitis) como efecto de los destartaradores de ultrasonidos.

In the present investigation we proposed the study of possible pulp damaged produced as a result of the application of an ultrasound scaler with 29 KHz output, commonly used in clinical vetereinary odontology. As an initial hypothesis, and based on bibliographic research, we considered that an application of more than 15 seconds, with maximun Coolant, meant a risk of dental pulp damage as a consequence of the rise in temperature produced by the vibration of the end of the ultrasound probe.

The method applied consisted of a series of previous measurements on experimental animals and finally on a group of six animals and one control animal. In each animal we used exclusivaly maxillary and mandibular premolars to which was applied double, four times and six times the recommended time, without the use of a coolant. At the same time temperatures were taken of the pulp canal the ambient temperature, the cheek, the gingival canal and the dentine of the affected tooth, using a probe with a termistor attached to a resistivity meter and inserted in the dentine to a depth of 1 mm.

Other data was also obtained on the thickness of the dentine and pulp cavity Once the colletion of data referring to the highest temperatures generated was complete, a waiting period of 2 weeks followed, after which a significant sample of dental pieces was removed for a histological study. In the control animal the temperature was raised to a limit of between 45ºC and 47ºC. Following this, all the premolars were removed for a histological stydy.

The results obtained make us conclude that the application of an ultrasound scaler of 29 KHz during 90 seconds continuous use on the dental surface, without coolant, does not incresease the tooth temperature. However, it can provoke damage comparable with acute pulpitis, as a consequece of the sonic effect caseded, very similar to the effects produced by the heat applied in the control animal.