New guidelines for graftless rehabilitation of the posterior maxilla

Abstract

Background The maxillary sinus anatomy varies according to age, population groups, sex and absence of teeth. Three-dimensional reconstruction and simulation of the maxillary sinus allows its classification into different categories based on the morphology of the inferior wall. Rehabilitation protocols for the posterior maxilla range from short implants, sinus graft, to zygomatic implants. This research proposes the creation of guidelines following three-dimensional classification of the maxillary sinus. Aim/Hypothesis It is possible to perform graftless rehabilitation of the posterior edentulous maxilla in a predictable way using dental implants. Material and Methods We performed a literature review on the treatment alternatives concerning the maxillary sinus anatomical categories. Following different sinus classifications, the authors proposed a decision matrix to categorize the different anatomical variations of the maxillary sinus. We applied specific rehabilitation models considering the different types of implant length, diameter and angulation versus the different three-dimensional categories and used real clinical cases to demonstrate the viability of the guideline for each category. Results Concerning the different sinus anatomy, there are six different classifications. The authors provided different graftless rehabilitation alternatives considering the use of standard implants (straight and tilted) and using the maxilla, together with the pterygoid or zygomatic bones for anchorage. The graftless rehabilitation alternatives are illustrated by clinical cases and discussed in the light of contemporary scientific literature and data from a series of cases. Considering the series of cases, the short term outcome was favorable with a high survival rate, low number of complications and patients’ reported satisfaction with function and aesthetics registered in all types of rehabilitations irrespective of the bone used for implant anchorage (maxilla only or in combination with pterygoid and zygomatic bone). Conclusion and Clinical Implications The commercial availability of grafting materials forced its indications spreading across a wider array of clinical presentations where otherwise conventional dental implants may be enough. It is possible to perform graftless rehabilitation of the edentulous posterior maxilla in cases where today many clinicians use bone substitutes as an alternative. The proposed clinical guidelines provide a treatment alternative using the maxilla, pterygoid or zygomatic bones for implant anchorage.