CRP--Studies of occlusal form and tooth arrangements, included balanced, lingualised and monoplane arrangements--lingualised posterior occlusion was preferred. Early studies on CRP design were observational as case reports, however data suggested that optimum function is achieved by modification of the maxillary occlusion, irrespective of the opposing mandibular occlusion. PRP--Edentulous ridge resorption is patient-specific, has a multifactorial aetiology and there is no objective data to confirm that mechanical factors cause bone loss; oral hygiene management is crucial for long-term health. Studies on distal extension PDs confirmed a link between bite force and masticatory function; preservation of two functioning posterior tooth units ipsilateral to the distal extension optimises function. Data indicate that patient-specific factors, rather than PD design-specific features, influence long-term PD outcomes. Implant superstructures--There is little scientific evidence specifying occlusal and superstructure design for fixed prostheses for teeth or implants. Occlusal scheme design and occlusal form have evolved through clinical experience, but there is no evidence to indicate that a particular design is superior. Complex neurophysiological mechanisms allow the jaw muscle system to accommodate to oral and dental changes.