The loss of tooth tissue and its subsequent replacement has always posed a challenge for both the clinician and the bio-material scientist. Whether lost by caries or as a result of the mechanical removal of diseased dentine, the substitution of dentine and enamel adequately to protect and support the tooth from further compromise and prevent sequelae leading up towards endodontic treatment, is a desirable feature in a successful restoration.
The importance of caries risk assessment has been well documented and in conjunction with preventative features is an integral part of the management process which influences the long term outcome. However the clinician is often faced with a situation as seen in figure 1 where the caries is deep within the dentine in close proximity to the pulp and restorative intervention is required.
The issue here for both the clinician and the patient is the predictability and indeed the desirability to maintain pulpal health and vitality and therefore an accurate diagnosis of the pulpal status is advantageous. However the methods commonly available for such evaluations may not be totally reliable. The partial removal of the caries mechanically has been well documented and this can help prevent iatrogenic trauma to the pulp. Use of a dentine and subsequent enamel substitute is required to restore the cavity and currently a single material may not fulfil all the desired properties required.
A distinct benefit would also be if the material were to induce reparatory changes within the tissues as well as providing structural support and reliable adhesion. Biodentine (Septodont) has shown potential for regeneration of the dentine –pulpal complex as well as other desirable restorative properties for a dentine replacement material.
From a clinical perspective in general practice there is an advantage to be able to offer the patient a restorative approach that aims to repair and restore the lesion as well as have the potential for sustainability of the vitality of the tooth; particularly when the periapical tissues show no radiographic signs of involvement nor any other conclusive diagnostic test result is obtained with regards the status of the pulp.
In this particular case the tooth (tooth 14) was symptomless and there were no changes in the periapical tissues detectable from the periapical radiograph (fig 2). Furthermore normal responses to sensibility testing via cold and electrical stimuli were noted. The caries was accessed and excavated (fig 3) and the cavity restored with Biodentine (fig 4).
After a period of waiting for two weeks the tooth was reviewed for symptoms and a normal response to sensibility testing was noted. A direct composite restoration was placed after the reduction of the Biodentine to accommodate the composite as an enamel substitute in a closed sandwich protocol. Figure 5 shows the composite restoration at the two-year recall. The adhesion of the material is via micro-mechanical anchorage of the mineral tags within the dentinal tubules. At the interfacial layer called the ‘mineral infiltration zone’, the alkaline caustic effect of the calcium silicate cement’s hydration products degrades the collagenous component of the interfacial dentine resulting in this infiltration. Compare this with glass ionomers where at the dentinerestorative interface the polyacrylic and tartaric acids and their salts characterise the penetration of the material.
The mixing and handling is crucial to the success of the material and protection during the setting mechanism is required. As shown in another case below (figures 6-9) after setting of the material, it is reduced and a bulk left behind to fulfil the requirements of a dentine substitute and allowing adequate room for the composite material.
In my experience patient acceptance of the material is high, this is facilitated by the potential advantage of the prospect that endodontic treatment could be avoided in a deep carious cavity.
Proper discussion regarding the benefits and indications for the use of this material with the patient is an important step towards obtaining informed consent.
Due to its properties and characteristics, Biodentine has applications in a variety of other clinical situations with particular indications in the management of endodontic perforations and cracked teeth. With the welcome drive towards minimal intervention, development of biomimetic materials that promote healing alongside established disease prevention protocols, a comprehensive successful approach towards patient management becomes achievable.
References available on request.