Dental Tribune U.S. Edition

COSMETIC TRIBUNE The World’s Cosmetic Dentistry Newspaper · U.S. Edition July 2011 www.dental-tribune.com Vol. 4, No. 7 Biomimetic principles applied to cosmetic dentistry By Susan M. McMahon, DMD and Emily Evron Biomimetic dentistry is based on the philosophy that the intact tooth in its ideal hues and shades and, more importantly, its intracoronal anatomy, mechanics and location in the arch, is the guide to recon- struction and the determinant of success. This approach is conser- vative and biologically sound and in sharp contrast to the porcelain- fused-to-metal technique in which the metal casting with its high elastic modulus makes the under- lying dentin hypofunctional. The goal of biomimetics in restorative dentistry is to return all of the prepared dental tissues to full function by the creation of a hard-tissue bond that allows func- tional stresses to pass through the tooth, drawing the entire crown into the final functional biologic and esthetic result.1 According to Douglas A. Terry, DDS, in dentistry there is no one biomaterial that has the same physical, mechanical and opti- cal properties as tooth structure (i.e., dentin, enamel, cementum) and possesses the physiological characteristics of intact teeth in function. By utilizing biomimetic therapeutic approaches, dentists can improve and become closer to natural biological structures and their function.8 There are two major perspec- tives to which the term “biomi- metic” is applied: a purist per- spective that focuses on recreating biological tissues and a descriptive perspective that focuses on using materials that result in a mimicked biological effect.8 Although differ- ent, both share a common goal of mimicking biology in restora- tion.8 This has been an increas- ingly common goal for dentists and patients alike in achieving esthetic and functional dentistry. Biomimetic dentistry techniques provide the patient with minimal- ly invasive options that conserve sound tooth structure as a clinical imperative.2 Biomimetics is essen- tially described as a mimicking of natural life, which can be accom- plished using contemporary com- posite resins and adhesive dental procedures.2 Conservation and bio- logical mimicry make up the foun- dation of a biomimetic philosophy and together produce the effect that today’s patients expect. From an esthetic/restorative perspective, biomimetics or bio- mimicry is the application of meth- ods and systems to artificially replace biologic elements in order to recreate optimal oral health.8 Practicing interdisciplin- ity and function of the respective areas (e.g., pulp, dentin, enamel, dentoenamel junction).8 The production of bone-, den- tine- and enamel-like biomaterials for the engineering of mineralized (hard) tissues is a high priority in regenerative medicine and den- tistry.10 The ability to manufacture such materials has allowed dental restorations to attain significantly more nature-like results that inevi- tably perform at a higher level than less life-like materials of the past. The physiological performance of an intact tooth requires a bal- ance between biological, mechani- cal, functional and esthetic param- eters in order to achieve biomi- metic qualities. This necessitates the develop- ment of “anatomical morphologi- cal thinking” when developing a restoration so that it replicates the natural tooth in form, function and esthetics.8 Such biological thinking will enable dentistry to focus on future health as well as the lasting appearance of the patients’ smiles, both of which are necessary for patient satisfaction. According to Wynn Okuda, DMD, “modifications to existing cavity design should be based on pres- ervation of natural dentition. The goals and objectives of biomimetic replacement should be to mimic the structure being replaced, thus allowing minimal removal of non- affected adjacent tooth structure.”8 Incorporating biomimetic princi- ples stems from somewhat of a philosophical approach to practic- ing dentistry, Okuda says.8 Dentists must take time to research methods of minimally invasive approaches to solving dental problems.8 Over billions of years, nature has created a formula for highly functioning materials that have withstood evolution. To create structures that will continue to function at such a level, dentistry must copy and integrate nature’s complex methods. Terry states that “we need to develop treatment modalities that allow us to repro- duce the biomechanical behaviors of the intact tooth. As research scientists, clinicians and techni- cians work together in understand- ing the complex orientation of this composite material called tooth ary esthetic restorative dentistry enables dentists to achieve biomi- metic results with cosmetic dentist- ry.8 These techniques and materi- als are crucial to modern dentistry in that they combine a focus on dental health and appearance. A biomimetic material should match the part of the tooth that it’s replac- ing in several important ways, including the modulus of elastic- Fig. 3: Note staining and discolored spots. Fig. 1: Preoperative smile. Fig. 2: Note the significant spacing between the upper and lower anterior teet