A Conservative Approach to Immediate Bone Grafting

INTRODUCTION

Bone preservation has become of paramount importance when tooth extractions are performed and full-arch dentures are indicated. Recently, research suggests that the physical and chemical composition of tooth-derived bone grafting materials makes them efficacious as an alternative bone grafting material in extraction sockets. This article discusses the characteristics of tooth-derived bone grafting materials, as well as the benefits of the chairside Smart Dentin Grinder device (KometaBio). A case presentation demonstrates the use of the device in the treatment of a patient who required extraction of her remaining maxillary dentition, immediate bone grafting, and delivery of an interim healing full-arch removable denture.

Numerous advancements have been made to enhance our patients’ oral health, including the prevention and treatment of periodontal disease as well as risk assessment and the management of caries disease. Unfortunately, many individuals still remain for whom the extraction of all teeth in one or both arches will be necessary and the replacement of lost teeth with an immediate full-arch removable prosthesis will be the most affordable and prudent treatment.1 However, even when undertaken in the most atraumatic manner possible, tooth extraction results in alterations to the hard and soft tissues that can compromise the fit and function of the prosthesis and contribute to aesthetic deficits and further bone resorption and soft-tissue collapse.2 For this reason, bone preservation has become of paramount importance when tooth extractions are performed and, in particular, when immediate full-arch dentures are indicated.3

Over the years, a variety of bone grafting materials has been utilized in combination with different ridge preservation and augmentation techniques. These have included allografts (ie, derived from human cadaver bone), xenografts (ie, derived from different species, such as bovine, porcine, equine, etc), autologous material (ie, derived from an individual’s own bone), and autogenous dentin (ie, derived from a patient’s extracted teeth).

Most recently in the literature, the physical and chemical composition of tooth-derived bone grafting materials has been studied. Reports indicate that the osteoconductive properties of these materials make them efficacious as an alternative bone grafting material.4,5 Additionally, because the materials can be produced from freshly extracted teeth and processed chairside using a dentin grinder (eg, the Smart Dentin Grinder), researchers have also cited this alternative’s availability and low cost as compared to other commercially available bone grafting materials.5

Contributing to dentin’s favorable use as a bone grafting material is its natural, bioactive, and autologous structure, which is virtually identical in composition to bone. When placed into an extraction socket, the tooth-derived dentin bone graft material does not resorb quickly but instead attracts osteoprogenitors from the site, essentially undergoing ankylosis (ie, fusion) with the bone.5 The fused bone/dentin matrix then remodels slowly, which in turn helps to maintain aesthetics. Still, more importantly, the matrix promotes new bone formation at the site due to the autologous nature of the graft.6,7 In fact, after 15 to 18 months of remodeling, the dentin particulate is usually no longer visible in the bone, and healing occurs without signs of inflammatory response.

A Chairside Approach

The Smart Dentin Grinder is a chairside device that converts a patient’s own tooth or teeth into autologous grafting material for placement back into the same patient. The device features a single-use grinding chamber that pulverizes the tooth into granules, then subsequently sorts them into 2 size ranges (eg, between 300 and 1,200 µm and smaller than 300 µm). Once the grinding procedure is finished, the granules are sterilized using chemical sterilization, although autoclave sterilization is also possible.

According to the manufacturer, testing has demonstrated that more than 98% of an original tooth processed by the Smart Dentin Grinder is ground, sorted, and recovered in the unit’s compartments. The dentist can use all granules that are produced or choose one size range if preferred. Additionally, the device has demonstrated effectiveness at grinding teeth consistently, regardless of variations in tooth morphology, as well as achieving consistent particulate sizing based on the sieves that sort the graft material.

The Smart Dentin Grinder offers 2 protocols: one for mineralized dentin grafts and a separate protocol for demineralized dentin grafts. The demineralized dentin graft protocol produces a combination of mineralized and demineralized particulate, which helps to expose the organic portion earlier while still maintaining an excellent, slow-resorbing mineral scaffold.

Interestingly, the Smart Dentin Grinder does not produce heat during the standard 3-second protocol (ie, the pulverization of the tooth structure, as opposed to grinding, cutting, or drilling). Therefore, there is no heat impact on the organic portion of the material, which is protected by the tooth’s mineralization.

The following case demonstrates the chairside use of the Smart Dentin Grinder when treating a patient who required extraction of her remaining maxillary dentition, im-mediate bone grafting, and delivery of an interim healing full-arch removable denture.