From Volume 40, Issue 4, May 2013 | Pages 297-317
For more than 40 years dentists worldwide have been using directly placed resin-bonded composite to restore damaged anterior teeth. While such techniques are invariably more conservative of tooth tissue than indirect procedures, operative techniques using direct composite can be challenging and are considered technique sensitive. Clinicians require both technical
In 1973, Dental Update published a prize-winning paper detailing a new application for resin composite in the restoration of a fractured central incisor of a ten year-old patient.1 While the procedure was considered a provisional method of long-term stabilization prior to a definitive indirect restoration, it was noted that the technique offered a number of benefits:1
Following the work of such early innovators, the last four decades have seen remarkable technological advances in the fields of aesthetic and, more recently, minimally invasive dentistry. The dental literature now even contains entire textbooks devoted to the aesthetic restoration of anterior teeth using direct composite.2,3
Operative techniques and materials with enhanced optical properties have been refined to such a highly sophisticated level that they present a first line approach,4 delivering predictable and reliable restorations5 of aesthetic and functional excellence,6 rivalling the best ceramics7 (Figure 1). The great popularity of composite resin restorations also results from their acceptable longevity at relatively low financial cost.8
While anterior composite restorations are ubiquitous, advanced multiple-layering techniques using a range of shades, opacities and translucencies remain the domain of relatively few practitioners.2 Dentists commonly report that such techniques are time-consuming or complicated and do not offer predictability in terms of aesthetics.2 Therefore, when aesthetic demands are high, many practitioners still resort to more destructive indirect procedures, relying on their technicians to employ well-established ceramic techniques to mimic the complex optical properties of natural teeth.
With the objective of reducing this tendency, this paper aims to provide:
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The main advantage of direct adhesive procedures is that they require minimal (or no) tooth preparation to enhance resistance and retention form6 (Figure 2). Multiple studies confirm that these conservative techniques offer a number of benefits compared to indirect restorations, including:9
It is a well-established fact that the appearance of a patient's teeth is an important psychological factor influencing his/her attractiveness and self-confidence.3,11 Techniques that enable the immediate restoration of aesthetics in a single appointment, requiring no provisional restorations and at a lower financial cost, are popular with patients.5,8,12
These versatile procedures are also professionally satisfying, as dentists are entirely in control of an aesthetic, biologically respectful technique, without the risk of communication errors that are common with indirect procedures.12 In common with the pioneering dentists of 40 years ago, practitioners using these minimally invasive techniques preserve all future treatment options.
Although direct techniques generally maximize tooth tissue preservation, it must be stressed that, as with any restorative procedure, an irreversible cycle of restoration replacement and repair begins with every operative intervention. The risk/benefit ratio must be considered at the outset and the patient informed of the potential short- and long-term complications that may ensue (Table 2) and his/her ongoing maintenance requirements.
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Regardless of material, the average survival statistics for direct restorations are far from encouraging.12,13 However, the figures for indirect restorations are also poor, averaging approximately ten years before restorations require total replacement13,14 and, when failure occurs, complications are often catastrophic for the tooth. With an optimum technique, it should be possible to provide direct composite restorations that exceed the average lifespan of indirect restorations and, in addition, retain the option of being able to increase their functional survival using conservative renovation techniques such as:
The main determinant of success in any direct adhesive procedure is based upon the operator's skill in optimizing assessment, diagnosis, treatment planning/ sequencing and execution and all operative stages.15 When providing restorations in the aesthetic zone, these demands must extend to detailed anatomical knowledge and artistic skill. Therefore it is essential to have comprehensive understanding with regard to:
The following summary of the fundamental principles of aesthetics in dentistry aims to provide the basis on which to design and carry out aesthetic direct restorations involving the maxillary anterior teeth.
A complex range of interrelated factors combine to determine the overall aesthetic properties of each individual patient's smile. Principles of ‘smile design’ are well-documented and the dental literature contains a number of excellent publications which provide guidelines for restoring the aesthetics of anterior teeth.17,18,19 It should be emphasized that these guidelines are not designed to form dogmatic rules to which all restorative procedures must adhere.
The facial and periodontal tissues are key ingredients in dental aesthetics.20 Useful guidelines for the relationships between teeth and these structures are as follows:17,18,19
When providing anterior restorations, it is useful to refer to widely recognized guidelines describing the key factors that influence the overall dental appearance.17,18,19,24 Tooth shape is generally considered to be the most important determinant of successful aesthetic integration.3,6 Furthermore, a restoration with the correct shape and surface texture is likely to integrate with the residual dentition successfully, even when small colour disparities exist2,3 (Table 3).
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This relates not only to the outline form of individual teeth, but also to their relative proportions and relationships to each other. Useful restoration guidelines include17,18,19 (Figure 5):
Following shape, restoration surface texture is the next most important factor influencing successful intergration3 and requires a detailed understanding of the equivalent anatomical features in natural teeth.2,3
The labial surface texture of young, unworn teeth is highly reflective and results in an attractive bright appearance (Figure 6).3 Surface texture features may be divided into three groups.
When incident light strikes the labial surface of an anterior tooth the majority is reflected back to the observer. This reflective area, which has various names (reflective face/zone; apparent face; silhouette form), is bordered by curved surfaces which deflect light giving a darker outline. The junctions of these zones, widely referred to as transition lines, are key features in restorative dentistry.2,3,16 Accurate positioning of transition lines in direct (and indirect) restorations is critical if restorations are to blend seamlessly with the residual dentition.6,16,19
This is referred to as macrotexture and includes:
This is referred to as microtexture and includes:
While tooth colour is not considered to be the prime factor determining successful restoration integration, it is still a vital component and is certainly the most complicated parameter. The dental literature contains numerous articles devoted entirely to the subject.25 The following outline describes aspects of tooth colour relevant to direct anterior restorative techniques.
Dentistry is amongst a number of disciplines that have adopted the famous Munsell system26 which describes colour in terms of three basic properties: hue, chroma and value.
Before selecting materials designed to mimic natural teeth it is essential to understand how the optical properties of the various tooth layers influence overall colour.6,12,24
Enamel, dentine, pulp and the amelo-dentinal junction (ADJ) all possess different optical properties, which are determined by their composition, structure and relative thicknesses. These tissues are constantly evolving via dynamic interaction with the extrinsic and intrinsic environments via numerous exchange processes.27 Numerous natural colour changes occur throughout life.
In terms of colour, dentine may be considered the most important layer.28 It provides most of the tooth's hue which falls in the yellow/red portion of the spectrum. In natural teeth, light passes through the translucent enamel and is reflected from the yellowish, relatively opaque dentine, which is approximately 20% less translucent than enamel4 (Figure 7).
Dentine colour varies from patient to patient and from tooth to tooth and changes throughout life.27,28 These variations are influenced by its composition, which is mainly mineral hydroxyapatite crystals (70%) supplemented by organic material (20%) and water (10%).
The organic component is partly responsible for making dentine more opaque than enamel.28 Opacity is further increased by its tubular structure which deflects some of the light rays entering the tooth.28
The dentine ‘core’ contour is as complex as enamel surface texture and comprises dentine lobes (usually three) divided by grooves labially and incisally. In unworn teeth, dentine terminates in the incisal third, short of the incisal edge.
The interface between enamel and dentine plays an important role in light transmission. It has a high mineral content and may be considered to have properties similar to a fibre-optic cable.28
Enamel is 95% mineral (5% water and organic components) resulting in largely translucent optical properties.27 The overall appearance of enamel depends on a complex interaction of factors2,3,29 (Table 4).
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For successful restoration integration, accurate replication of translucency is considered to be almost as important as value.29 The translucency of natural enamel (and restorative material) is strongly influenced by its thickness27,29 (Figure 8).
Cervical enamel is thin (average 0.2–0.3mm in young teeth)27 and highly translucent, allowing the more chromatic dentine to show through and creating a considerably more opaque appearance.28 Moving incisally enamel thickness increases and it becomes less translucent. In the incisal third, enamel is thickest (average 1.5mm)27 and may possess a localized bluish, opalescent effect27 (Figure 8).
When very fine hydroxyapatite crystals are illuminated by light in the visible range of the spectrum, short wavelength light is scattered.27 Reflected light results in a blue/grey/violet appearance, often extending to the proximal surfaces and transmitted light results in amber/reddish/ orange effects. While these iridescent phenomena may occur across the entire labial surface, it is more evident in the incisal third, where there is no interference from dentine.2,28
Dental hard tissues (particularly enamel and the ADJ) also fluoresce when struck by invisible/short wave ultraviolet light, reflecting it back as visible, bluish longer wavelengths.16 Therefore, for successful integration, dental materials should possess fluorescent properties.
Localized mineralization differences, of varying aetiologies, are common in tooth structure and may result in unusual colourations. Detailed classifications16,30 provide useful guidance when copying these features in composite resin (Table 5). Central incisors generally have more elaborate incisal characterization than lateral incisors.6
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Naturally occurring fissures (enamel lamellae) and cracks resulting from functional forces fill with air and water, effectively dividing the enamel surface into portions with differing optical properties.28 These features also allow the passage of stains which may extend to the dentine layer and may be simulated using pigmented composite resins.
Even the naturally dark red colour of pulpal tissue has an influence on tooth colour and can result in a pinkish appearance, which reduces as pulp volume decreases with age.28
Young enamel is thick, with lower mineral content, creating high value tooth colour. With age, mineral content increases and enamel thins due to natural wear. This results in an increase in enamel translucency, which may be pronounced or even transparent, allowing the dentine colour to show through.
Young dentine is very opaque. With age, dentine become less opaque but has more colour saturation as highly mineralized secondary dentine is laid down. Tertiary dentine, which has varying structure and composition, will also influence tooth chroma.
The ADJ translucency increases with age and it can sometimes become completely transparent.
Extrinsic and intrinsic stains can have a potent effect on tooth colour over time and this may be partially or completely reversed by tooth whitening procedures.
When restorative procedures aimed at improving tooth colour are planned, it is often recommended to carry out whitening procedures first, reducing the need to mask darker colours with opaque materials. Following tooth whitening, it is not recommended to carry out adhesive restorative procedures for at least two weeks, to avoid the negative effects of oxygen inhibition and to allow colour stabilization.31
Having studied the anatomical and optical properties of natural tooth tissue, it should now be possible to select appropriate materials, equipment and techniques judiciously for the accurate, predictable, aesthetic restoration of anterior teeth using direct composite.
As with any restorative procedure, a thorough understanding of materials science enables selection of composite resins suitable for each clinical situation and optimizes the restoration of function and aesthetics.
A wide range of composites is available for the restoration of anterior teeth, all with subtly different formulations, which can be confusing.8 Prior to purchase, practitioners are recommended to study, test and select materials based on their fundamental physical properties rather than focusing on their marketing literature. Filler content determines a material's mechanical properties and influences volumetric shrinkage. As with posterior composites, hybrid materials are commonly used, as their combination of large and small filler particles provides the strength necessary to withstand functional forces.15
Filler particle composition and filler/resin refractive index mismatch are among the most important variables in determining the optical properties of individual materials.32
Where high functional forces are not anticipated, resins containing low average filler particle size (microfills) may be selected for their superior polishability properties.
All procedures using direct resin placement are considered technique sensitive.15 Therefore, for successful, predictable restorations, materials must be selected that possess the handling characteristics favoured by individual practitioners.12,15
For clinical situations, where aesthetic demands are high, the majority of manufacturers supply materials in multiple shades. These are designed to be placed using stratification techniques similar to those used by dental ceramists6 (Table 6).
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While the perfect composite with optical properties identical to those of enamel and dentine does not exist,2,33 the dental literature now contains a growing number of ground-breaking publications detailing the seemingly limitless capabilities of direct composite for the precise restoration of damaged teeth, in a comprehensive range of clinical situations.2,3,4,6,8,12,16,24,29,30,32,34,35,36,37
Analogous to natural tooth tissue, the appearance of dental restorations is influenced by shape, surface texture, translucency/opacity, value, chroma and hue, with each property combining to affect the final outcome.
While shape and surface texture are still considered of greatest importance, predictable shade matching is an essential requirement for all practitioners and a number of techniques are available to facilitate this process.
While shade guides are included with most composite systems, unfortunately they are generally considered to be inaccurate and unsuitable for precise colour matching for a number of reasons:2,3,4,8,12,35,38
Various techniques have been described that aim to overcome the limitations of commercially available shade guides and include:
Various technique tips have been identified to improve precision when selecting shades for direct (and indirect) restorations, including:
As enamel loses water rapidly, shade selection should be carried out as early as possible and before isolation.3 Dehydration blocks the passage of visible light and this decrease in refractive index causes enamel (and dentine) to become lighter and more opaque, in less than three minutes.2
Maximum dehydration is reported to occur 30–45 minutes after isolation2 and complete rehydration may not occur for 24–48 hours.2 Dehydration also masks the internal colour characteristics.3
For these reasons, experienced practitioners refer to a pre-operative photograph or diagram of well-hydrated teeth to guide their placement sequences. This is commonly referred to as a colour map.6,12,16,30
A good photograph used with an appropriate shade guide is reported to be the most precise method of colour communication.16 Digital images may be underexposed or manipulated with software to reveal characteristic internal features, particularly occurring in the incisal third16 (Figure 10).
As with all restorative procedures, functional integration is as important as that required for aesthetic blending. Restoration of guiding palatal surfaces using direct techniques presents challenges, but can be simplified by using a template constructed from a prototype restoration or a pre-operative wax-up3,6,7,34 (Figure 11).
The initial palatal composite increment may be applied to a template made of conventional silicone putty or specialized transparent material before or after insertion into the mouth. Once light-cured, the palatal shell immediately establishes the three dimensional form of the whole restoration.12
In certain clinical situations, tooth preparation may be avoided completely, eg fracture repair (Figure 12) or diastema closure (Figure 2).
Where preparation is necessary, it should be minimized and confined to the enamel to optimize adhesion and reduce the risk of marginal staining.
Natural cavity undercuts or pulp chambers/root canals of endodontically treated teeth may also be used to enhance retention.34 Particle air abrasion may be employed to clean cavities and increase the surface area available for micro-mechanical and chemical retention.4 In certain clinical situations, it may be necessary to bevel enamel margins to assist retention and to mask the transition between tooth structure and the restorative material.
Opinion varies on the size and form (eg scalloping7) of enamel bevels or whether discs, ultrasonic tips or rubber points should also be used to remove fragile enamel from preparation margins.3
While use of a rubber dam is far from commonplace,41 it is generally considered to be the optimum method of moisture control for adhesive restorative procedures2,15 (Figure 13).
Following isolation with a rubber dam, stabilizing cord, wedges or floss ligatures may be used to optimize the seal and prevent the dam partially obscuring adjacent teeth which are being used to guide restoration shape.
Another useful isolation technique for Class III, IV and V restorations involves the use of gingival retraction cord, which may be soaked in an astringent product.34
There is a variety of matrices designed for anterior composites restorations involving proximal surfaces. They are made from a number of translucent polyester materials, commonly referred to by the brand name Mylar. They are available in a number of shapes including: full contour crown forms, strips and specially designed sectional matrices designed to facilitate restoration of the complex curvature of anterior teeth.3 Matrices should be secured with suitable wedges to minimize cervical excess, provide tooth separation and soft tissue control and stabilize the rubber dam.3,15 Thin metal sectional matrices designed for posterior composites may also be used or ‘dead soft’ foil wrapped around adjacent teeth.
A popular technique employs plumber's tape (Polytetrafluoroethylene (PTFE) tape). This inexpensive, inert, non-sticky material is usually wrapped around adjacent teeth to protect them from etch, adhesive, and excess composite. PTFE tape is of negligible thickness promoting tight contact formation34 and it does not interfere with adaptation of silicone templates.
Before etching, cavities must be thoroughly washed, dried and inspected for any debris. Starting with enamel, etchant is applied to the entire cavity and just beyond the margins. Excessive etchant should not extend beyond this area, to prevent excess composite adhering and being difficult to remove without iatrogenic damage to underlying enamel. When application to the dentine is complete, it is left for 15 seconds and then rinsed off thoroughly.
With total etch systems, enamel can be dried to a ‘frosty’ appearance but dentine desiccation should be avoided. This also promotes adhesion to dentine and reduces the risk of post-operative sensitivity.12,15 Unprepared enamel should be etched for longer (30–60 seconds)42 to optimize adhesion to the acid-resistant aprismatic surface layer of enamel.
As successful adhesion is a fundamental requirement for long-lasting restorations. Fastidious attention must be given to manufacturers' protocols.15
Self-etching adhesives are not recommended when restoring cavities that lack sufficient resistance and retention form (eg Class IV), as they contain weaker acids that will not sufficiently penetrate enamel to a depth that maximizes resin-tag formation.43
Before light-curing, all cavity surfaces should appear glossy/shiny.15
A wide range of placement protocols have been proposed for anterior resin composites. With multiple cavities the general recommendation is to restore the central incisors first, one at a time, following the aesthetic principles previously described.34 Once complete, restoration of lateral incisors and then canines is carried out.6
Proficient operators tend to slightly overbuild restorations before reducing them to correct contour. This avoids the need for time-consuming additions, which may also lead to visible layers/voids between increments.3
All composites shrink during polymerization and create stresses, with the potential to cause a range of well-documented complications.15
Fortunately, the wide, open configuration of many anterior cavities allows restorative material particles to flow during their polymerization reaction. This relaxes stresses and often permits placement of larger increments than those recommended for cavities with a less favourable configuration factor.
Composite increments may be injected from compules or applied using a variety of instruments. Practitioners are recommended to master placement techniques with a select range of instruments designed for the purpose.2,15 Composite may be warmed using specialized (or improvised) heaters to enhance adaptation to the cavity and between increments.16 The common practice of lubricating instruments with adhesive agents should be avoided as they contain solvents that may dilute composite resin materials and have negative effects on their physical, optical and surface staining properties.44
Solvent-free modelling liquids, eg Biscover (Ultradent), Enaseal (Micerium), are also available, but their use is not universally recommended,2,3 other than to recover the oxygen inhibited layer following corrections to subsurface increments using rotary instruments.2
Despite technological advances in contemporary composite systems, the majority of practitioners use monochromatic materials for anterior composites.2 Such techniques are ideally suited for small cavities but they may deliver sub-optimal aesthetic outcomes in more aesthetically important areas.
Although placement of successive increments helps to minimize the effects of polymerization shrinkage stress, aesthetic layering techniques are considered problematic3 and less predictable than those which use a single material.
Errors in layering techniques result in restorations which appear too translucent or opaque.
The thickness relationship of opaque dentine composites and translucent enamels is the key to successful layering techniques.2,29 The overall outcome is determined by the propagation of light as it passes through these layers to create an illusion of depth, equivalent to that seen in natural teeth 6,32,36 (Figure 14).
Unfortunately, a ‘utopian’ material, engineered to replace enamel and dentine in their exact dimensions, does not exist.2 To avoid restorations having an excessively translucent, grey-looking appearance, it is widely recommended to apply enamel composite layers in thicknesses no greater than half that of the total enamel thickness.2
A wide range of composite stratification techniques, of varying complexity, have been described.2 To ensure predictable, aesthetically pleasing results, layering concepts should be simple, standardized and reproducible.3
The following basic dual-shade and more complicated multi-layered (polychromatic) placement sequences are presented as methodical guidelines for all clinicians wishing to create more natural looking direct anterior composite restorations.
Inexperienced practitioners are recommended to develop confidence in layering techniques by beginning with two material shades, as this simplified technique is reported to deliver an acceptable colour match in a large number of clinical situations.2
Following etching and adhesive application, an opaque dentine material is applied, shaped and light-cured (Figure 15a, b). Most dentine restorative materials (and 80% of natural dentine) are in the shade group A and selection of the correct chroma is a key to success.2 Palatal, proximal and labial enamel increments are then layered, freehand over the opacious central core at approximately half the thickness of residual enamel (Figure 15c, d).
When aesthetic demands are high, the widely accepted stratification technique proposed by Lorenzo Vanini is recommended.16 As each clinical situation presents different aesthetic challenges, study of detailed atlases2,3 describing the comprehensive range of layering options is highly recommended. The fundamental principle of polychromatic layering technique is to use different composite shades to replicate the layers seen in natural teeth,32,37 as demonstrated in Figure 16, which is now described in stages.
A palatal ‘shell’ of translucent enamel composite is light-cured in place. In this example, using a silicone template made from a pre-operative wax-up (Figure 16a, b, c).
To avoid a monochromatic appearance, dentine lobes are restored using progressively chromatic increments2,3,16 (three in this example) (Figure 16d, e, f). The dentine build-up should stop short of the incisal edge and should be shaped into lobes, leaving room for the incorporation of materials designed to replicate the appropriate optical properties of the incisal third.2,3,16
These are very case specific. In natural teeth, they are generally optical properties of enamel, but materials aiming to mimic these features are ideally placed before the final enamel layer2 (Figure 16g).
‘Painting’ these features on the surface layer often appears artificial, because it lacks the quality of depth and may wear off. When the translucent enamel material is subsequently applied and polished these features show through, producing very natural appearances, such as the incisal ‘halo effect’.6,16
Materials designed to replicate special features may be divided into opalescents, characterizations and intensives16,30 and are usually applied in that order.
Opalescent materials are placed in spaces left between the dentine lobes and, if required, extended into mesial and distal proximal spaces.2,3,6,16
Opalescent composite transmits light more efficiently and is designed to reproduce the iridescent optical properties commonly seen in the incisal third.2 The degree of opalescence is judged by the amount of blue that the material shows under direct light and amber features seen under transmitted light. Composites specifically designed to recreate opalescent effects include Trans Opal (Empress Direct; Ivoclar), OBN (Enamel Plus HFO, Micerium) and Effect Blue (Miris 2, Coltène Whaledent).
Two generalized groups of material may be used to create opalescent effects: tinted flowable materials or artificially achromatic enamel (AAE) composite,12 which is inherently pigmented and not keyed to the Vita shade system.6 Either material may be used to impart various degrees of translucency and subtle hues, ranging through grey, blue, violet, amber, to milky white.
Experienced clinicians are capable of precisely reproducing a diverse range of characterizations, including those listed in Table 5.2,3,16,30
Intensives are used to recreate white spots or patches in teeth found with hypoplastic and hypomineralization defects. White features vary in opacity extent and lack opalescence. A range of tinted conventional and flowable materials may be applied using suitable instruments or brushes (Figure 17) or mixed to copy unusual colourations.2 It is recommended to use them sparingly to avoid obviously unnatural appearances12 and to refer to an adjacent tooth or a pre-operative colour map.
The final layer generally comprises an enamel or incisal material with smaller average filler particle size with translucent (and often opalescent) optical properties that modify those of the underlying layers (Figure 16h).
It is advisable to minimize the time spent manipulating superficial increments to reduce the risk of incorporating air bubbles, which may affect the optical properties and/or be revealed during finishing and polishing procedures.2 The final layer may be slightly overbuilt and then finished and polished to the correct incisal edge thickness. It is recommended that the total enamel thickness should be a maximum of half of the thickness of the natural enamel that it replaces (or maximum thickness of 0.5mm)3 to prevent restorations being too translucent, too low in value and not life-like.2,6
While various alternative light-curing regimes have been proposed, general recommendations include: regular equipment checks using appropriate light intensity meters; light-curing for a suitable duration (usually at least 60 seconds) from all angles; keeping the light tip as close to the material as possible and avoidance of premature polymerization by ambient light.16 A layer of translucent material, such as glycerine, may be placed over the final increment.34 This minimizes contact with oxygen which inhibits surface polymerization.
Shape is the most important factor in the final appearance of an aesthetic restoration.2 It is therefore essential that the primary anatomical features of natural teeth are meticulously reinstated using appropriate burs, discs and finishing strips (Figure 18). Initial shaping may be carried out using red-stripe (30–40 µm) composite finishing burs. When shaping a single central incisor, the adjacent tooth should be studied to re-establish symmetry by making the reflective face of both teeth equal.3
Repositioning of transition lines can change the appearance of poorly shaped teeth, making them appear aesthetically pleasing even though their outline remains the same.3
Functional surfaces should be designed and contoured so that both the restoration and tooth can tolerate the anticipated occlusal forces.6 In patients with parafunction, more fracture resistant, large particle, hybrid composite is recommended, which may be veneered with a more aesthetic/polishable microfill or small particle nano-hybrid material.
The correct shape must be established before refinements are made; if this is not done the finishing and polishing process will tend to magnify any errors.
Finishing and polishing are well-researched procedures45,46 and play an essential role in the way that light interacts with the restoration.2 The natural secondary and tertiary surface texture features may all be simulated in direct restorations, using a variety of equipment (Figure 19), including:6
A methodical approach is required to complete each finishing and polishing procedure before moving on to the next. Great care should be taken to avoid iatrogenic damage to tooth surfaces and adjacent periodontal tissues. Copious water spray and a light touch should be used as rotary finishing equipment can generate significant heat. This may damage hard and soft dental tissues, restorative material, and adhesive interfaces or destroy finishing burs designed for multiple uses.2,15
Restorations should never be painted with adhesive agents containing solvents. Although this will deliver a short-lived shine, surface degradation will rapidly encourage stain formation. The time taken to shape, finish and polish anterior composite restorations accurately will deliver reliable, aesthetic, long-lasting restorations equivalent to those made from ceramic.
Composite resin materials absorb water which is attracted to the filler particles altering the optical properties of the restoration.40 For this reason, fine finishing and polishing procedures may be postponed to a second appointment when shade stabilization has occurred. Clinicians will also be able to reflect on the functional and aesthetic outcome and carry out any necessary adjustments.
As with all direct and indirect procedures, patients must be informed at the outset of the importance of restoration maintenance and the need for regular reviews to allow assessment and renovation or repair in the longer term.
Successful anterior composites are satisfying for both patients and clinicians. The time taken to study dental aesthetics and practise and refine operative techniques2 (Figure 20) will be rewarded on a daily basis. Direct adhesive procedures have almost limitless potential to restore function and aesthetics, while preserving healthy tooth tissue and, as such, anterior composites are at the very forefront of contemporary minimally invasive aesthetic dentistry.
