Poor bone quality is a important factor to consider when it comes to implant treatment.This is a term often used to denote regions of bone in which there is low mineralization or poor trabeculation.It is often associated with a thin or absent cortex and is referred to as type 4 bone.It is a normal variant of bone quality and is more likely to occur in the posterior maxilla.Osteoporosis is a condition that results in a reduction of the bone mineral density and commonly affected postmenopausal females,having its greatest effect in the spine and pelvis.The effect of osteoporosis on the maxilla and mandible may be of little significance in the majority of patients.Many patients can have type 4 bone quality,particularly in the posterior maxilla,in the absence of any osteoporotic changes.