5th class in Business Class
Fifth class cavities are very common in the population, and they seem to become more and more frequent, thus becoming a relevant topic to clinicians and a problem for a lot of patients.
The number of patients who have experienced Cervical Tissue Loss (CTL) is, in fact, growing and the incidence has shown a continuous increase over the years.
The CTL can involve hard tissues and soft tissues: this situation requires a multidisciplinar approach using a combined restorative and periodontal treatment.
It is really important to start with a proper etiologic diagnosis. The main causes for CTL:
Acids: this category embraces all forms of chemical, biochemical and electochemical degradation.
Abrasion: Toothbrush / toothpaste action
Abfraction: microfracture of tooth substance in areas of stress concentration.
Because of the complex interaction of these various mechanisms, it is generally incorrect to designate all CTLs as being caused by only one mechanism. The clinician should consider all etiological and modifying factors before completing the diagnosis or initiating treatment if indicated.
The restoration of CTL is a big challenge for clinicians and adhesive materials, due the biomechanical aspects, the type of substrate availabe for the adhesion and the isolation of the operative field.
One of the problems could be the isolation: the Lesion can be so cervical that the difference between the buccal/lingual and the vestibular level of the healthy tooth can make the placing of the rubber dam really difficult or almost impossible using a clamp. The situation is different if we manage the isolation of the operative field using a dedicated instrument capable of acting, at the same time, as a gentle rubber-dam and as a soft tissues retractor, useful to expose the working area.
B) If the lesion is deep cervical it is possible to modify the clamp to reach the healthy tissue, but the working angle will allow only a really flat restoration and may require a lot of finishing and polishing at the end.
C) To maintain a good working angle the clamp could damage the buccal gum.
D) The solution is to use a Gengiva instrument able to push the rubber dam and compress the gum only from the vestibular side.
B) Gengiva try in.
C) Gengiva and rubber dam in place.
Step by step
Achieving a good emergence profile in 5th class restorations can be simple. This technique helps to always use the rubber dam in 5th class restoration, to have a correct shape with the minumun need of finishing procedures; to obtain the correct emergence angle of the reconstruction and avoid flat restorations. The best gum healing process is usually associated with restorations that correctly reproduce the lost anatomy of the tooth: the anatomy is usually “curvy”, using Gengiva it is possible to have a proper working angle; having an open angle is important to mold the restoration emergence profile.
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