Free excerpt - SAC Classification in Implant Dentistry

A. DAWSON, W. MARTIN, W. D. POLIDO

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Fig 14 a–b. (a) A patient with missing maxillary anterior teeth and associated high esthetic risk. (b) View of the edentulous area.

3.5 Edentulous Esthetic Risk Assessment (EERA)

L. GONZAGA, W. MARTIN, D. MORTON

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In fully edentulous scenarios, esthetic issues occur when implant-supported prostheses inadequately support or blend with the facial structures, teeth, smile line, and resid- ual alveolar ridge. The EERA is a component of the SAC clas- sification. It functions as an independent tool capable of identifying key risk factors that influence esthetic outcomes. These factors are relevant when managing patients with a terminal dentition or when fully edentulous. The systemat- ic use of the EERA checklist during the diagnosis and plan- ning phase can decrease the risk of esthetic as well as tech- nical and biologic complications. Publications focusing on management of the fully edentu- lous mandible with prostheses supported by dental im- plants report high survival and success rates, and low rates of esthetic complications (Polido et al, 2018; Malo et al, 2011). These findings are likely due to the anatomy of the lower two-thirds of the lower one-third of the face, including the lip and its surrounding muscles and the influence of the prosthesis on facial support, the smile line, and phonetics (minimal disruption of speech seal) (Figure 15). Alternatively, themanagement of the fully edentulous max- illa is more challenging and requires meticulous planning (Desjardins, 1992). The challenges associated withmanage- ment of the maxilla are well-recognized and can be associ- ated with specific anatomical characteristics, bone resorp- tion patterns, quality of bone, need for prosthetic volume, importance of emergence profile, oral hygiene limitations, influence of the teeth and hard tissue during speech, and the importance of the prosthesis for facial and dental es- thetics (Schnitman, 1999; Zitzmann & Marinello, 2000; Tay- lor, 1991). In 2017, Pollini and coworkers emphasized the

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Fig 15. Facial proportions.

challenges associated with management of the edentulous maxilla and developed the lip-tooth-ridge (LTR) classifica- tion. The LTR classification offers a guide for treatment plan- ning the edentulous maxilla for fixed or removable prosthe- ses (Figure 16). Utilization of the LTR classification assists clinicians in identifying esthetic risk based on a combina- tion of lip dynamics as well as structural risk based upon prosthetic space availability. It should be recognized that treatment of the edentulous maxilla will increase esthetic risk due to the need for opti- mal facial and lip support, the relationship between the ideal tooth position, the lip, and the alveolar ridge, as well as the need for specific prosthesis design to minimize pho- netics complications or speech issues.

Congress Lecture The Edentulous Maxilla – Fixed vs. Removable for Esthetic Outcomes by Nicola Ursula Zitzmann.

The SAC Classification in Implant Dentistry

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