Plaque and calculus deposits around teeth can lead to gum infections and can further lead to attachment loss, bone loss and teeth mobility. Systemic disease like diabetes influence host response and further increase the incidence of gum disease and tooth mobility. If teeth are loose because of gum diseases, then dental cleaning and root planning can be done. After bacteria are removed from teeth and surrounding areas, gums will re-grow over it and mobility of teeth is reduced. Periodontal gum surgery may also be required to save the teeth. If teeth are very loose and can’t be saved, then they can be removed and can be replaced with dental implants. Dental implants are best option for replacement of missing teeth. Bone grafting procedure may be required before giving dental implants. You can take your father to a periodontist who is gum specialist.  For more info on remedies for loose teeth, visit…….   http://www.identalhub.com/dental-remedies-for-loose-tooth-524.aspx