The atrophic posterior maxilla and the appropriate treatment approach can be categorized in four groups.

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Expanded sinus cavity with limited bone height for implant placement
Expanded sinus cavity with limited bone height and inadequate bone width for implant placement
Expanded sinus cavity with extreme vertical atrophy
Expanded sinus cavity with extreme vertical atrophy, insufficient bone width, and large vertical intermaxillary distance
SFE in combination with horizontal and vertical ridge augmentation with block graft
No need for procedures other than SFE due to ideal interarch relations
SFE may be combined with vertical ridge augmentation
SFE in combination with horizontal ridge augmentation