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.

style italiano styleitaliano dentistry

Fig.1
The Cervical Tissue Loss could extend below the gum, and be really cervical.

style italiano styleitaliano dentistry

Fig.2
A) clamp in place: if the lesion is not big and not deep cervical the working angle is correct.
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.

style italiano styleitaliano dentistry

Fig.3
Working angle in deep cervical lesion using a clamp.

style italiano styleitaliano dentistry

Fig.4
Working angle in deep cervical lesion using LM Gengiva.

style italiano styleitaliano dentistry

Fig.5
The blue plastic working ends available in three sizes, can tightly adapt to the gingival margin in different teeth, and make the gum protection and retraction easy.

style italiano styleitaliano dentistry

Fig.6
Deep cervical lesion.

style italiano styleitaliano dentistry

Fig.7
Deep cervical lesion using Gengiva.

style italiano styleitaliano dentistry

Fig.8
The goal is to obtain a proper emergence angle of the restoration.

style italiano styleitaliano dentistry

Fig.9
It is the proper instrument to isolate this lesion Advantages of this technique are: Easy exposure of healthy tissue, if the access to the margin is clear, it will be easier to model the 5th class restoration, resulting less finishing and polishing time, and less hard and soft tissue damage. The fast and atraumatic procedure minimize the post-operative discomfort for the patient. Disadvantages: The instrument has to be hold in place by the operator’s hand during the procedure time.

style italiano styleitaliano dentistry

Fig.10
A) pre-operative image.
B) Gengiva try in.
C) Gengiva and rubber dam in place.

style italiano styleitaliano dentistry

Fig.11
Sometimes it is necessary to adapt the plastic working end.

Step by step

style italiano styleitaliano dentistry

Fig.12
Pre-operative view

style italiano styleitaliano dentistry

Fig.13
1) LM Gengiva in place, to test the gum compression, gently air spray to evaluate the sensitivity. If the patient refers discomfort go for anesthesia; if the patient refers no thermal sensitivity or discomfort it is possible to proceed without anesthesia.

style italiano styleitaliano dentistry

Fig.14
If the blue plastic working end is too wide, could prevent correct adaptation of the rubber dam.

style italiano styleitaliano dentistry

Fig.15
Use a disc to reshape the blue plastic working end

style italiano styleitaliano dentistry

Fig.16
Tooth side pre-adhesive procedures: enamel bevel to achieve the best aesthetic result. Margin definition important especially in cases of not big cavities not to miss the restoration limit it is a very gentle sign. Healthy tissue reactivation, to expose ”fresh tissue” and remove the sclerotic one.

style italiano styleitaliano dentistry

Fig.17
It is important to fully drag the dam with Gengiva, finding the correct angle.

style italiano styleitaliano dentistry

Fig.18
Air-spray glycine to clean the operative area

style italiano styleitaliano dentistry

Fig.19
Selective etching and adhesive procedures.

style italiano styleitaliano dentistry

Fig.20
Composite stratification, from the incisal to the cervical surface following Closing Gap strategy (Style Italiano – Work in progress)

style italiano styleitaliano dentistry

Fig.21
Finishing

style italiano styleitaliano dentistry

Fig.22
Finishing

style italiano styleitaliano dentistry

Fig.23
Finish and polish with rubber dam in place, using Kavo Eva handpiece (reciprocating-action instrumentation) bevel tips, scaler and and silicone rubber-based composite finishing instruments.

style italiano styleitaliano dentistry

Fig.24
Time zero

style italiano styleitaliano dentistry

Fig.25
One week later

style italiano styleitaliano dentistry

Fig.26
Only enamel lesion, start from cleaning the surface by sonic handpiece and glycine air spray

style italiano styleitaliano dentistry

Fig.27
Gengiva small size. Sandblast with aluminum dioxide 27 micron particles using air and water spray handpiece, then etch.

style italiano styleitaliano dentistry

Fig.28
On the left surface post etching. On the right Universal adhesive.

style italiano styleitaliano dentistry

Fig.29

style italiano styleitaliano dentistry

Fig.30

Conclusions

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.

Bibliography

Borcic J, Anic I, Urek MM, Ferreri S. The prevalence of non-carious cervical lesions in permanent dentition. J Oral Rehabil. 2004 Feb;31(2):117-23.
Grippo JO, Simring M, Coleman TA. Abfraction, abrasion, biocorrosion, and the enigma of noncarious cervical lesions: a 20-year perspective. J Esthet Restor Dent. 2012 Feb;24(1):10-23.
Allegri MA, Landi L, Zucchelli G.? Non-carious cervical lesions associated with multiple gingival recessions in the maxillary arch. A restorative-periodontal effort for esthetic success. A 12-month case report. Eur J Esthet Dent. 2010 Spring;5(1):10-27.
Loi I, Di Felice A. Biologically oriented preparation technique (BOPT): a new approach for prosthetic restoration of periodontically healthy teeth. Eur J Esthet Dent. 2013 Spring;8(1):10-23.
Jaeggi T, Lussi A: Prevalence, incidence and distribution of erosion. Erosive tooth wear – from diagnosis to therapy, Monogr Oral Sci. Karger, Basel, 25: pp 55–73 (2014)
Carvalho TS, Colon P, Ganss C, Huysmans MC, Lussi A, Schlueter N, Schmalz G, Shellis PR, Björg Tveit A, Wiegand A. Consensus Report of the European Federation of Conservative Dentistry: Erosive tooth wear diagnosis and management. Swiss Dent J. 2016;126(4):342-6.

RELATED CASES

Teeth Recontouring and Shape Perfecting

In this article we will show how we can use direct composite veneers to correct the alignment and also modify the shape of teeth to make a smile beautiful.
styleitaliano style italiano silicone index positioning under rubber dam isolation

Double-mold Technique