Implant therapy has proven to be a successful treatment modality that is applicable across a wide range of clinical indications for tooth replacement. In step with wider use of implant therapy, the demands on the esthetic outcome have also grown. This module is aimed at assisting clinicians with assessment and discussion of these outcomes with their patients.

After completing this ITI Academy Module, you should be able to define implant esthetics, assess esthetic outcomes, identify cases of esthetic compromise, and recognize esthetic complications.

The 3rd ITI Consensus Conference defined the esthetic zone from two perspectives. Objectively, the esthetic zone applies to any dentoalveolar segment that's visible in a full smile. Subjectively, it applies to any dentoalveolar area of esthetic importance to the patient. On this basis, the esthetic zone will vary from patient to patient depending on the level of the lip lines and expectations for the outcome. In the example, the patient has a high lip line and discloses both anterior and posterior teeth and their associated soft tissues.

The 3rd ITI Consensus Conference also defined esthetic implant prostheses as being in harmony with the perioral facial structures of the patient and the healthy surrounding dentition and imitating the natural original appearance of the missing dental unit or units. In these images, the replacement of a failed natural upper left lateral incisor with a fixed implant-supported crown has achieved an appearance that is in keeping with its natural predecessor and with the contralateral tooth.

Building on these definitions, an optimal esthetic outcome can be defined as a perfect illusion that is maintained over time. In this close-up photo, congenitally missing maxillary lateral incisors have been replaced with implant-supported fixed dental prostheses that succeed in creating the illusion that the teeth as well as the soft tissues have always been present.

A prerequisite to ensuring that the optimal esthetic outcome is maintained over time is the continued stability of the supporting implants and the peri-implant hard and soft tissues as well as the continued stability of the prostheses. To meet this requirement, all three aspects must present without complications, fulfill defined criteria over the observation period, and satisfy patient-centered outcomes. When these conditions are not met, an esthetic complication can arise. More detail on the criteria for continued success and survival of implants, and on the complications that can result when they are not met, can be found in the ITI Learning Module 'Implant and Prosthesis Survival and Success'.

Implant Esthetics, Key Learning Points: The boundaries of the esthetic zone vary based on the patient's lip line and expectations. Implant prostheses are considered to be esthetic when they mimic natural teeth and are in harmony with the surrounding oral environment. When the implant, hard and soft tissues, and/or prosthesis are not stable over time, the esthetic outcome is compromised, and an esthetic complication may arise.

A benchmark is helpful in the assessment of esthetic outcomes. Such benchmarks are especially useful when they allow objective scoring that can be repeated by others or compared. Over time, multiple indices or scoring systems have been proposed for assessing the esthetics of both the prosthetic tooth and adjacent soft tissues. The most widely accepted are the white esthetic score or WES and the pink esthetic score or PES. The pink esthetic score was first described by Fürhauser and co-workers in 2005 and later modified by Belser and colleagues in 2009 to correspond more readily to a novel white esthetic score that they had developed to assess the visible part of the implant prosthesis.

The white esthetic outcome score assesses multiple tooth parameters including tooth form, outline and volume, color, surface texture, and translucency and characterizations. For each of these parameters a score is applied with 0 signifying a major discrepancy, 1 a minor discrepancy, and 2 for no discrepancy as compared to the contralateral tooth. In this example the upper right central incisor implant crown is indistinguishable from the upper left natural tooth and would therefore satisfy a maximum score of 10.

The modified pink esthetic score suggested by Belser and co-workers in 2009 uses a similar, simplified scoring method as shown here. The score assesses various parameters in comparison to contralateral teeth, including the level of the papillae, curvature of the facial mucosa, level of the facial mucosa, and root convexity as well as soft tissue color and texture. The status of the adjacent teeth and their proximal bone levels are relevant to the total score. The patient's periodontal phenotype and the underlying thickness and level of facial bone are also relevant. In this clinical example of an implant-supported tooth replacement for the upper right central incisor, the underlying bone ensures support for the mucosal papilla and midfacial mucosal margin. However, loss of bone on the mesial aspect of the natural right lateral incisor has resulted in recession of the distal papilla in comparison to the contralateral papilla on the left, so the total score would be, at best, a 9.

The fifth parameter of root convexity is best appreciated in this more occlusal view. In this example it is clear that the highest score of 2, for no discrepancy, can be applied.

The WES and PES apply to single-tooth implants adjacent to natural teeth only. They therefore do not allow for objective assessment of prostheses replacing multiple adjacent teeth. Multiple missing teeth create esthetic challenges. Loss of bony support for the proximal papilla between two adjacent implant prostheses will, in many cases, lead to an esthetic compromise. This is illustrated here, where the implant-supported fixed crowns on the upper right central and lateral incisors have been contoured carefully to achieve a harmonious esthetic outcome despite the significant difference in the interproximal papilla volume and level compared with the contralateral teeth. Evaluation of these esthetic compromises will be addressed in the next Learning Objective.

Esthetic Outcomes, Key Learning Points: The pink and white esthetic scores are the most widely accepted methods of objectively assessing the esthetic outcome of single-tooth implant crowns. The implant-supported crown or soft tissue is compared with the contralateral tooth on the basis of clinical parameters. A maximum score of 10 indicates no discrepancy between implant-supported and natural teeth. Loss of bone support between adjacent implants often leads to esthetic compromise associated with flattening of the papilla.

Esthetic compromise can be defined as an expected outcome where both patient and clinician accept certain limitations and agree that it is the best possible esthetic outcome given the circumstances. In this clinical example an implant has been placed, but the patient has opted to have the prosthesis fabricated and inserted elsewhere. Using the white and pink esthetic scores as a basis for initial assessment of the best possible esthetic outcome, it is clear that there will be a compromise in a number of parameters, including tooth outline and level of the facial mucosa and distal papilla. Fortunately, the patient also has a low smile line, and an esthetic result that is acceptable to the patient has been achieved with the provisional prosthesis.

An esthetic compromise may be dictated by the implant placement or by factors related to structures adjacent to the treatment site. In discussion of esthetic outcomes with the patient it is very helpful to be clear on the etiology of a compromise. The ITI Esthetic Risk Assessment or ERA was developed for planning, but it can also be used for a retrospective analysis. The ERA considers a number of factors that can have potential impact on the esthetic outcome; these are covered in detail in a dedicated ITI Academy Learning Module titled 'Esthetic Risk Assessment'.

Esthetic compromise is likely to increase with multiple tooth replacements. It is not possible to preserve the interproximal peaks of bone between two teeth if both are removed. There will be an inevitable flattening of the bone and therefore also flattening of the mucosa overlying the bone. When adjacent implants replace these teeth, the loss of papilla support poses a challenge to the clinician when recreating both white and pink esthetics of the natural teeth.

Esthetic compromise may also arise out of the original reason for tooth loss. In situations of stabilized periodontal disease, esthetic compromise may be related to earlier bone loss, flattening of papillae, and unavoidable interproximal spaces. In this clinical example, the patient has accepted the interproximal spaces between the upper anterior implant-supported prostheses because they are in harmony with similar spaces between the lower teeth. In another case, teeth were lost as a result of trauma. The patient decided against extensive augmentation and instead opted to accept a compromise in both the white and pink esthetic outcomes. The patient has a low smile line that disguises the cervical aspect of the implant-supported prostheses replacing the upper central and left lateral incisors.

Patients may have very definite ideas about the esthetic outcome they desire. These ideas may be based on a perception of what the original teeth were like or an ideal based on images seen in the media or on the internet. When these ideas do not align with the residual dentition overall, an esthetic compromise may arise. In this example, the denture tooth moulds selected for the initial diagnostic set-up of teeth had incisal edges and tooth forms that blended harmoniously with the natural teeth. By contrast, the patient preferred central incisors with very straight-sided teeth and squared incisal edges, as seen in the definitive prosthesis. Combined with long clinical prosthesis crowns, the outcome is undoubtedly a compromise.

The level of patient expectations is the first and, in many ways, most critical factor in esthetic success. It is therefore also the first question asked in the ITI SAC Tool for determining level of complexity of a given implant patient case. Patient expectations can be divided into high versus low and realistic versus unrealistic. The patient shown in this image has high but also realistic expectations of the esthetic outcome. The long neck of the upper right lateral incisor implant crown is harmonious with the varied gingival levels of the upper anterior teeth. Moreover, prosthetic imitation of a root surface in both shape and shading assists in creating the illusion of a natural tooth with recession. The patient shown in a second example, however, presented with existing implant crowns replacing the upper right lateral incisor, lower right canine, and three lower incisors. The esthetic compromise - and oral hygiene challenge - of a centrally placed implant supporting the replacement of the lower central incisors was acceptable to the patient.

With the increased focus on optimal esthetic outcomes, it may be tempting to critique the esthetic results of past treatment based on today's standards and with the benefit of hindsight. As a general rule, it is sensible to ascertain the patient's opinion of an esthetic result before commenting on it. Equally, a clear understanding of the etiology of the compromise and prospects for improvement is important before raising patient concern and expectations. The patient may be reasonably satisfied with an esthetic outcome that the clinician judges to be unacceptable. In that case, it is preferable to leave well alone. For the patient shown, provided that the health and function of the upper left central and lateral incisor implant crowns are satisfactory, esthetic comments should be limited until the patient expresses dissatisfaction with their appearance.

Esthetic Compromise, Key Learning Points: An esthetic compromise is the best possible esthetic outcome given the specific circumstances and limitations of a clinical case. The Esthetic Risk Assessment can be used both to anticipate an esthetic challenge and to analyze an esthetic outcome. A history of periodontal disease, trauma, or adjacent missing teeth all predispose the patient to an esthetic challenge. Patient ideas and expectations may not be realistic or consistent with the achievable esthetic outcome. It is important to be sensitive to the patient's opinion of the esthetic outcome.

A complication may be defined as an unexpected deviation from a normal treatment outcome. Specifically for implant therapy, an esthetic complication is associated with an unexpected outcome of implant therapy in the esthetic zone. In the patient shown, despite hard tissue augmentation to increase the width of the facial bone, marked mucosal recession has subsequently occurred on the upper left lateral incisor. This is very clearly visible in the smile.

As for the compromised esthetic outcome, the white and pink esthetic scores can be used to assess the extent of the esthetic complication. In the example seen here of an upper right central incisor, the complication is affecting the esthetics of both the prosthesis and the adjacent mucosal tissues. The difference in incisal levels between the implant crown and the contralateral natural central incisor is due to continued growth. The mucosal recession and exposure of the one-piece transmucosal implant collar is most likely due to loss of the facial bone wall.

The esthetic concern may apply to several units at the same time, and often evaluation of complications will also be closely linked to scope for management and seeking improvement. Fortunately, the esthetic concerns in the patient on the left are associated with the more posterior units, and the patient has decided to accept the mucosal recession as is. In the situation on the right, the esthetic concern regarding the gap between the central incisors, which is visible in the smile, is linked to the esthetic complication caused by the placement of too many implants too close together in an area with insufficient bone and soft tissue. Despite a careful attempt to optimize the white esthetics in the coronal half of the implant crowns, esthetic management of the apical half is needed. A removable labial gingival veneer in carefully tinted pink acrylic is an option.

In evaluation of the esthetic outcome it is important to ascertain the etiology of the complication. By definition, a complication is an unexpected outcome. However, a complication may not always be truly unexpected but instead simply be unanticipated by the implant clinician team. In cases where complications arise out of iatrogenic factors, it is essential that these factors are recognized and correctly diagnosed prior to any attempts at management. In the patient on the right, the implant was placed too far facially to be incorporated into the prosthesis; this placement also led to the esthetic complication of facial bone loss, exposure of the endosseous implant portion, and mucosal recession.

In addition to assessment of the etiology, the nature of the complication may also dictate the urgency with which it should be addressed. The mucosal discoloration seen in these images is considered more chronic in nature, and while this outcome may be of great concern to the patient, immediate management may not be required. On the other hand, the swelling and fistula seen in the middle image is of an urgent nature, and acute complications such as these should be addressed soonest to avoid further damage. In another example, surgical intervention after fistula formation disclosed retention of excess cement associated with a deeply placed prosthesis margin.

Esthetic Complications, Key Learning Points: An esthetic complication is an unexpected outcome of implant therapy in the esthetic zone. Any esthetic complications must be scrutinized for possible iatrogenic causes. Improvement and management of the esthetic outcome is affected by the extent of the complication. Esthetic complications of an acute nature should be addressed urgently.

Principles of Evaluating Esthetic Outcomes, Module Summary: An optimal esthetic outcome relies on the continued stability of implants, peri-implant hard and soft tissues, and prostheses. Objective methods of evaluation such as the pink and white esthetic scores are useful tools for objectively assessing an esthetic outcome and comparing it over time. Various patient circumstances can lead to an esthetic compromise including the implant site, adjacent teeth and tissues, or the dentition as a whole. Patient ideas about their dentition can contribute to an esthetic compromise; conversely, realistic patient expectation levels can result in acceptance of a compromised esthetic result. Clinicians should refrain from commenting on an esthetic result until they are aware of the patient's feelings or opinion. An esthetic complication is an unexpected or unanticipated result that requires careful assessment and management, particularly if the complication is the result of clinician failure in diagnosis, treatment planning, or provision of implant treatment.