In Scientology, an implant is a form of Thought insertion, similar to an engram but done deliberately and with evil intent. It is "an intentional installation of fixed ideas, contra-survival to the thetan".

The intention in the original engram or incident is to implant an idea or emotion or sensation, regarding some phenomenon etc. The intention in Scientology and Dianetics is to erase the compulsive or command effect of the idea, emotion, sensation, etc. so that the person can make a rational judgment and decision in the affected areas of life.

Scientology practices often have to do with addressing implants prior to the current lifetime — one of the most notable is the "R6 implant"; but in some cases current life implants are addressed. Examples of implants according to Scientology include Aversion therapy, Electroconvulsive therapy, hypnosis, various attempts at brainwashing, and the inducing of fear or terror. Note that this is not a complete list, as many kinds of incidents can include implants as an element.

Other important implants in Scientology doctrine include the Helatrobus implants, which Hubbard claimed occurred 382 trillion years ago to 52 trillion years ago by an alien nation called the Helatrobans, who sought to restrain human minds by capturing and brainwashing thetans. These implants are said to be responsible for the concept of Heaven.

Pectus excavatum occurs in an estimated 1 in 150 to 1 in 1000 births, with male predominance (male-to-female ratio of 3:1). In 35% to 45% of cases family members are affected.

Researchers are unsure of the cause of pectus excavatum but assume that there is a genetic component for at least some of the cases as 37% of individuals have an affected first degree family member. As of 2012, a number of genetic markers for pectus excavatum have also been discovered.

Pectus excavatum is a relatively common symptom of Noonan syndrome, Marfan syndrome and Loeys-Dietz syndrome and sometimes is found in other connective tissue disorders such as Ehlers–Danlos Syndrome. Many children with spinal muscular atrophy develop pectus excavatum due to their diaphragmatic breathing. Pectus excavatum also occurs in about 1% of persons diagnosed with celiac disease for unknown reasons.

Metallosis is the putative medical condition involving deposition and build-up of metal debris in the soft tissues of the body.

Metallosis has been hypothesized to occur when metallic components in medical implants, specifically joint replacements, abrade against one another.

Metallosis has also been observed in some patients either sensitive to the implant or for unknown reasons even in the absence of malpositioned prosthesis. Though rare, metallosis has been observed at an estimated incidence of 5% of metal joint implant patients over the last 40 years. Women may be at slightly higher risk than men. If metallosis occurs, it may involve the hip and knee joints, the shoulder, wrist, or elbow joints.

The abrasion of metal components may cause metal ions to be solubilized. The hypothesis that the immune system identifies the metal ions as foreign bodies and inflames the area around the debris may be incorrect because of the small size of metal ions may prevent them from becoming haptens. Poisoning from metallosis is rare, but cobaltism is an established health concern. The involvement of the immune system in this putative condition has also been theorized but has never been proven.

Purported symptoms of metallosis generally include pain around the site of the implant, pseudotumors (a mass of inflamed cells that resembles a tumor but is actually collected fluids), and a noticeable rash that indicates necrosis. The damaged and inflamed tissue can also contribute to loosening the implant or medical device. Metallosis can cause dislocation of non-cemented implants as the healthy tissue that would normally hold the implant in place is weakened or destroyed. Metallosis has been demonstrated to cause osteolysis.

Women, those who are small in stature, and the obese are at greater risk for metallosis because their body structure causes more tension on the implant, quickening the abrasion of the metal components and the subsequent build-up of metallic debris.

According to the National Human Genome Research Institute, Poland syndrome affects males three times as often as females and affects the right side of the body twice as often as the left. The incidence is estimated to range from one in 7,000 to one in 100,000 live births.

As the grinding components cause metal flakes to shed from the system, the implant wears down. Metallosis results in numerous additional side effects:

- Confusion;

- Feelings of malaise;

- Gastrointestinal problems;

- Emotional disturbance;

- Recurring infections;

- Dizziness;

- Headaches;

- Problems in the nervous system (feelings of burning, tingling, or numbness of the extremities); and

- Cobalt poisoning (skin rashes, cardiomyopathy, problems with hearing, sight or cognition, tremors, and hypothyroidism).

The exact cause of Kienböck's is not known, though there are thought to be a number of factors predisposing a person to Kienböck's.

Recent studies have made a correlation between Kienböck's sufferers and Western European ancestry, but no definitive link can be positively confirmed.

The necrosis of the lunate bone can frequently be traced to a trauma to the wrist, like a compound fracture, which could cause the lunate's blood supply to be interrupted. Blood flows to the lunate through several arteries, each supplying a percentage. When one of these pathways is severed, the likelihood the patient will develop necrosis increases.

Despite a preponderance of evidence, no particular cause has been conclusively verified.

Data exists on the internet that most people suffering from Kienböck's are affected in their dominant hand, though about one-third of sufferers report the condition in their non-dominant hand. In very few cases have there been people that have acquired it in both wrists.

Kienböck's disease is classified as a "rare disorder," meaning that it affects fewer than 200,000 people in the U.S. population.

Many Kienböck's patients are frustrated by the lack of consensus among hand surgeons about optimal treatments for Kienböck's. No matter what the disease's stage of progression, there is no one best treatment, and the decision is often based partially, or even mostly, on incidental factors such as the patient's pain tolerance, the patient's desire to return to active use of the hand (such as in manual occupations), and the surgeon's level of expertise with different treatments.

Though, since each case of Kienböck's is different, the makeup of the wrist and arm bones are important factors which are individualized to each patient. Therefore, one surgery will never be able to solve all the problems associated with the disease. Thus, no consensus can be reached among surgeons.

The cause of Poland syndrome is unknown. However, an interruption of the embryonic blood supply to the arteries that lie under the collarbone (subclavian arteries) at about the 46th day of embryonic development is the prevailing theory.

The subclavian arteries normally supply blood to embryonic tissues that give rise to the chest wall and hand. Variations in the site and extent of the disruption may explain the range of signs and symptoms that occur in Poland syndrome. Abnormality of an embryonic structure called the apical ectodermal ridge, which helps direct early limb development, may also be involved in this disorder.

Physiologically, increased pressure "in utero", rickets and increased traction on the sternum due to abnormalities of the diaphragm have been postulated as specific mechanisms. Because the heart is located behind the sternum, and because individuals with pectus excavatum have been shown to have visible deformities of the heart seen both on radiological imaging and after autopsies, it has been hypothesized that there is impairment of function of the cardiovascular system in individuals with pectus excavatum. While some studies have demonstrated decreased cardiovascular function, no consensus has been reached based on newer physiological tests such as echocardiography of the presence or degree of impairment in cardiovascular function. Similarly, there is no consensus on the degree of functional improvement after corrective surgery; A 2013 meta-analysis yielded conflicting results.

According to Rinker's research, there are several key factors. A history of cigarette smoking "breaks down a protein in the skin called elastin, which gives youthful skin its elastic appearance and supports the breast." The number of pregnancies was strongly correlated with ptosis, with the effects increasing with each pregnancy. As most women age, breasts naturally yield to gravity and tend to sag and fold over the inframammary crease, the lower attachment point to the chest wall. This is more true for larger-breasted women. The fourth reason was significant weight gain or loss (greater than ). Other significant factors were higher body mass index and larger bra cup size.

The aging process has three distinct components: physiologic degeneration, extrinsic damage (nosocusis), and intrinsic damage (sociocusis). These factors are superimposed on a genetic substrate, and may be overshadowed by general age-related susceptibility to diseases and disorders.

Hearing loss is only weakly correlated with age. In preindustrial and non-industrial societies, persons retain their hearing into old age. In the Framingham cohort study, only 10% of the variability of hearing with age could be explained by age-related physiologic deterioration. Within family groups, heredity factors were dominant; across family groups, other, presumably sociocusis and nosocusis factors were dominant.

- Heredity: factors like early aging of the cochlea and susceptibility of the cochlea for drug insults are genetically determined.

- Oxidative stress

- General inflammatory conditions

In Rinker's study, 55% of respondents reported an adverse change in breast shape after pregnancy. Many women mistakenly attribute the changes and their sagging breasts to breastfeeding, and as a result some are reluctant to nurse their infants. Research shows that breastfeeding is not the factor that many thought it was. Rinker concluded that "Expectant mothers should be reassured that breastfeeding does not appear to have an adverse effect upon breast appearance." Also discounted as causes affecting ptosis are weight gain during pregnancy and lack of participation in regular upper body exercise.

Kienböck's disease is a disorder of the wrist. It is named for Dr. Robert Kienböck, a radiologist in Vienna, Austria who described osteomalacia of the lunate in 1910.

It is breakdown of the lunate bone, a carpal bone in the wrist that articulates with the radius in the forearm. Specifically, Kienböck's disease is another name for avascular necrosis (death and fracture of bone tissue due to interruption of blood supply) with fragmentation and collapse of the lunate. This has classically been attributed to arterial disruption, but may also occur after events that produce venous congestion with elevated interosseous pressure.

Several symptoms are common but not specific:

- Dull, throbbing, ache in the joint which can be brought on by very strenuous exertion or simple household chores.

- Difficulty sleeping due to shoulder discomfort. The SLAP lesion decreases the stability of the joint which, when combined with lying in bed, causes the shoulder to drop.

- For an athlete involved in a throwing sport such as baseball, pain and a catching feeling are prevalent. Throwing athletes may also complain of a loss of strength or significant decreased velocity in throwing.

- Any applied force overhead or pushing directly into the shoulder can result in impingement and catching sensations.

Orbital fractures, in general, are more prevalent in men than women. In one study in children, 81% of cases were boys (mean age 12.5 years). In another study in adults, men accounted for 72% of orbital fractures (mean age 81).

Nosocusis factors are those that can cause hearing loss, which are not noise-based and separate from pure presbycusis. They may include:

- Ototoxic drugs: Ingestion of ototoxic drugs like aspirin may hasten the process of presbycusis.

- vascular degeneration

- Atherosclerosis: May diminish vascularity of the cochlea, thereby reducing its oxygen supply.

- Dietary habits: Increased intake of saturated fat may accelerate atherosclerotic changes in old age.

- Smoking: Is postulated to accentuate atherosclerotic changes in blood vessels aggravating presbycusis.

- Diabetes: May cause vasculitis and endothelial proliferation in the blood vessels of the cochlea, thereby reducing its blood supply.

- Hypertension: causes potent vascular changes, like reduction in blood supply to the cochlea, thereby aggravating presbycusis.

However, a recent study found that diabetes, atherosclerosis and hypertension had no correlation to presbycusis, suggesting that these are nosocusis (acquired hearing loss) factors, not intrinsic factors.

Craniofrontonasal dysplasia is a very rare genetic condition. As such there is little information and no consensus in the published literature regarding the epidemiological statistics.

The incidence values that were reported ranged from 1:100,000 to 1:120,000.

A SLAP tear or SLAP lesion is an injury to the glenoid labrum (fibrocartilaginous rim attached around the margin of the glenoid cavity). SLAP is an acronym for "superior labral tear from anterior to posterior".

Common medical causes of blowout fracture may include:

- Direct orbital blunt injury

- Sports injury (squash ball, tennis ball etc.)

- Motor vehicle accidents

False memory syndrome (FMS) describes a condition in which a person's identity and relationships are affected by memories that are factually incorrect but that they strongly believe. Peter J. Freyd originated the term, which the False Memory Syndrome Foundation (FMSF) subsequently popularized. The term is not recognized as a psychiatric illness in any of the medical manuals, such as the ICD-10 or the DSM-5; however, the principle that memories can be altered by outside influences is overwhelmingly accepted by scientists.

False memories may be the result of recovered memory therapy, a term also defined by the FMSF in the early 1990s, which describes a range of therapy methods that are prone to creating confabulations. Some of the influential figures in the genesis of the theory are forensic psychologist Ralph Underwager, psychologist Elizabeth Loftus, and sociologist Richard Ofshe.

The etiology, or cause of edentulism, can be multifaceted. While the extraction of non-restorable or non-strategic teeth by a dentist does contribute to edentulism, the predominant cause of tooth loss in developed countries is periodontal disease. While the teeth may remain completely decay-free, the bone surrounding and providing support to the teeth may reabsorb and disappear, giving rise to tooth mobility and eventual tooth loss. In the radiograph at the beginning of the article, tooth #21 (the lower left first premolar, to the right of #22, the lower left canine) exhibits 50% bone loss, presenting with a distal horizontal defect and a mesial vertical defect. Tooth #22 exhibits roughly 30% bone loss.

Congenital cystic eye (also known as "CCE" or "cystic eyeball") is an extremely rare ocular malformation where the eye fails to develop correctly "in utero" and is replaced by benign, fluid-filled tissue. Its incidence is unknown, due to the very small number of cases reported. An audit by Duke-Elder of the medical literature from 1880 to 1963 discovered only 28 cases. The term was coined in 1937 by the renowned ophthalmologist Ida Mann.

Embryologically, the defect is thought to occur around day 35 of gestation, when the vesicle fails to invaginate. Dysgenesis of the vesicle later in development may result in coloboma, a separate and less severe malformation of the ocular structures.

CCE is almost always unilateral, but at least 2 cases of bilateral involvement have been described. Patients may also present with skin appendages attached to the skin surrounding the eyes. Association with intracranial anomalies has been reported.

Treatment of CCE is usually by enucleation, followed by insertion of an ocular implant and prosthesis.

OAF is a complication of oroantral communication. Other complications may arise if left untreated. For example:

- Candidal infection

- Chronic maxillary sinus infection of bacterial origin

- Osteomyelitis

- Rhinosinusitis

- Sinus pathology

Therefore, OAF should be dealt with first, before treating the complications.

Prosthetic replacement of missing teeth is possible using dental implant technology or dentures. This treatment can be successful in giving patients with anodontia a more aesthetically pleasing appearance. The use of an implant prosthesis in the lower jaw could be recommended for younger patients as it is shown to significantly improve the craniofacial growth, social development and self-image. The study associated with this evidence worked with individuals who had ectodermal dysplasia of varying age groups of up to 11, 11 to 18 and more than 18 years. It was noted that the risk of implant failure was significantly higher in patients younger than 18 years, but there is significant reason to use this methodology of treatment in those older. Overall the use of an implant-prosthesis has a considerable functional, aesthetic and psychological advantage when compared to a conventional denture, in the patients.

False memory syndrome is a condition in which a person's identity and interpersonal relationships center on a memory of a traumatic experience that is objectively false but that the person strongly believes occurred.

The FMS concept is controversial, and the Diagnostic and Statistical Manual of Mental Disorders does not include it. Paul R. McHugh, member of the FMSF, stated that the term was not adopted into the fourth version of the manual due to the pertinent committee being headed by believers in recovered memory.

Studies have shown that sinusitis is found in about 60% of the cases on the fourth day after the manifestation of sinus. Moreover, patient may be afflicted with an acute sinus disease if OAC is not treated promptly upon detecting clear signs of sinusitis. So, early diagnosis of OAC must be conducted in order to prevent OAF from setting in.

Spontaneous healing of small perforation is expected to begin about 48 hours after tooth extraction and it remains possible during the following two weeks. Patient must consult the dentist as early as possible should a large defect of more than 7mm in diameter or a dogged opening that requires closure is discovered so that appropriate and suitable treatment can be swiftly arranged or referral to Oral Maxillofacial Surgery (OMFS) be made at the local hospital, if required.

A comprehensive preoperative radiographic evaluation is a must as the risk of OAC can increase due to one or more of the following situations :-

- Close relationship between the roots of the maxillary posterior teeth and the sinus floor

- Increased divergence or dilaceration of the roots of the tooth

- Marked pneumatization of the sinus leading to a larger size

- Peri-radicular lesions involving teeth or roots in close association with the sinus floor

Hence, in such cases:

- Avoid using too much of apical pressure during tooth extraction

- Perform surgical extraction with roots sectioning

- Consider referral to OMFS at local hospital