Monday, February 16, 2009

A NEW SET OF TEETH


A dental implant is an artificial substitute for a normal tooth. Natural teeth are lost due to damage in accidents, poor dental hygiene, genetic and other factors. Dental implants using the new Zygoma technique give the patient a new tooth or set of teeth through a treatment that is quick with long-lasting effects and almost pain-free.

What is a dental implant?

The normal tooth structure consists of a root and a crown. The root is enclosed in the jawbone and gums and the crown is the visible part of the tooth.

A dental implant is an artificial substitute for the root. It is usually made of titanium, which is a bio-compatible material i.e. it will not be rejected by our body.

After a healing period, an artificial crown is placed on top of the implant. Thus the implant closely resembles a natural tooth.

How many teeth can be replaced with implants?

If all the teeth are missing, the complete set of teeth in the jaw can be supported by four or six implants. The number of implants is determined on a patient to patient basis, depending on criteria such as bite force, location of missing teeth, quality of jawbone…

Are implant teeth fixed or removable?

Implants are placed in, fixed and integrated to the jaw bone. However the artificial teeth placed on top of the implant can be fixed or removable. The former is more common.

What are the benefits of dental implants?

They feel and look like your own teeth. Dental implants restore confidence in speaking, laughing and chewing with comfort and without worries of sudden dislodgement. Implants preserve the integrity of facial structures.

When teeth are replaced using traditional tooth-supported bridges, the teeth on either side of the missing tooth are ground down so that the bridge can be cemented on to them. This structure can never be replaced. Implants do not need the grinding down of the adjacent natural teeth.

Can anyone receive dental implants?

The patient must be in good health and have proper bone structure and healthy gums for a successful implant. People who are unable to wear removable dentures may also be good candidates. Patients with well-controlled diabetes or blood pressure can also undergo implants.

In patients with bruxism(grinding or clenching teeth) and poor oral hygiene, heavy smokers or those who have undergone radiation therapy in the jaw, the success rate for implants reduces.

Does the treatment take a long time?

Usually the treatment is done in two phases. In the first stage, the implant is placed in the jaw and the gums are closed over it.

After a healing period of three to six months, the implant will be checked and measurements made for the artificial teeth (prosthesis) ,which will be placed over the implant.

However, thanks to the combination of CT Imaging Technology and software for implant planning, implants are placed as a ‘key hole’ procedure and artificial teeth are fixed immediately on the implant within an hour.

This ‘teeth in an hour’ concept, however, has a few pre-requisites such as normal volume of jawbone, good range of mouth opening and adequate primary stability of the implant.

Does the patient need to be hospitalised?

Hospitalisation is an exception and not the rule. Majority of patients can be managed under local anaesthesia. Anxious patients are helped with nitrous oxide sedation or intravenous sedation techniques. A few patients, especially those requiring extensive bone grafting, will require general anaesthesia.

Can implants be done for elderly people?

Implants can be done in older people also. However certain issues such as osteoporosis (especially in post-menopausal women not on HRT), long history of heavy smoking, uncontrolled diabetes have to be kept in mind while planning implants.

Can implants be done for children?

Implants are generally contra-indicated in growing ages. Continued jaw growth can lead to altered implant levels and difficulty in fabricating the artificial teeth. However, in certain conditions such as ectodermal dysplasia, implants can be given during childhood.

What is Zygoma Implant?

In some patients, the upper jaw bone is not adequate to take implants. In such cases the hip bone is grafted into the upper jaw. Later implants are placed and artificial teeth fixed. In the new zygoma technique, bone grafting is not necessary.

The zygoma implant is a longer implant, which is placed in the upper jaw bone extending up to the zygoma (cheek bone) and artificial teeth are placed on it (without the need for extensive bone grafting procedure).

F&Q ON STEM CELL TRANSPLANT


Recently there have been a number of articles on stem cell transplantation, which has generated lot of interest among the public. By definition a stem cell is one capable of self renewal and multiplication. Every living tissue has its origin from the stem cell.

Stem cell transplantation was first used in the treatment of blood disorders and it was a breakthrough. Conventionally known as bone marrow transplantation, the stem cells responsible for production of the blood cells reside in the bone marrow, which is a special tissue inside the cavity of the bones. The blood cells originate from the bone marrow from a parent cell or the "stem cell".

A more comprehensive terminology for bone marrow transplantation is haematopoietic stem cell transplantation or blood stem cell transplantation.

The word Haematopoiesis means blood cell production, which includes red cells, white cells and platelets.

What are the sources of haematopoietic stem cells?

The sources are bone marrow; from the blood circulation, also known as peripheral blood stem cells and Umbilical cord blood.

How is the stem cell obtained from the donor?

To collect stem cells from the bone marrow, the donor is given general anaesthesia and bone marrow is aspirated from multiple sites in the hip bone and collected in a bag. This takes about one to two hours depending on the quantity required, which again depends on the weight of the patient. There is usually no risk to the donor.

To collect stem cells from peripheral blood, the donor is given a special injection called growth factors to stimulate production of the stem cells in increased numbers. These will be circulating in the blood stream.

The donor is connected to a machine called the cell separator machine, which can separate the stem cells from the donor’s blood and return the rest of the blood to the donor.

How is the blood stem cell given to the patient?

It is given simply as an intravenous infusion like blood transfusion. The stem cells will automatically find their way home, which is the bone marrow. It will replace the patient’s diseased marrow to give healthy blood cells.

What are the prerequisites for transplants?

The main prerequisite is that the blood group should match. It is common knowledge that if a patient requires blood transfusion only the same group has to be used. Similarly for transplanting blood stem cells there is a system called Human Leucocyte antigen or HLA. These are proteins present on the surface of most of the cells. This system recognises self from non-self.

If a patient is exposed to stem cells with a different HLA antigen specificity, the patient’s immune system will recognise the stem cells as foreign and reject it.

Before a patient is scheduled for blood stem cell transplantation, it is mandatory to choose a donor with an identical HLA type. This can be checked by simple tests.

Who can be the donors for blood stem cell?

Siblings of the patient or a twin; Extended family members; Unrelated donors

What are the chances that a sibling will have identical HLA?

The HLA system for each individual is derived from both parents. Each individual inherits a set of antigens (proteins) from each parent. There is a one in four chance that the individual will have a HLA identical sibling. If there is no sibling donor, one has to explore options with extended family members or unrelated donors.

How are unrelated donors identified?

In the developed countries, there is a national bone marrow donor registry. It enrols voluntary donors who are willing to donate their bone marrow. The bone marrow registry maintains their data base with their HLA typing. Their fitness to donate marrow is also assessed.

The bone marrow registry is linked to other international registries. If a patient needs blood stem cell transplantation and if the patient has no suitable family donor, a search is made through the national registry on the electronic data base.

What is the consequence to the donor?

Bone marrow is a replenishable tissue. Donating bone marrow is more or less like donating blood. So there is no damage to the donor.



A donor is connected to a machine that separates stem cells from the blood.

What are the other sources?

Umbilical cord blood is a recent source, which shows great promise for patients who lack a family donor. Umbilical cord blood is rich in blood forming stem cells. Umbilical cord is the connecting link between the mother and the foetus.

Once the baby is born the umbilical cord is severed and disposed off. The discovery that the umbilical cord blood is a rich source of blood stem cells has led to the formation of cord blood banks around the world and the cord blood stem cells are stored for lifesaving purposes.

There are a number of private and public cord blood banks in many countries and it is networked.

What are the advantages of cord blood stem cells?

Cord blood stem cells are easily available. The degree of matching required between the patient and the donor can be less stringent compared to conventional bone marrow transplantation.

What are the diseases that can be treated by this method?

It can be classified into three main groups of diseases. Malignant diseases like Leukaemia or cancer of the blood cells; diseases where blood production itself is defective like Aplastic anaemia; and genetic diseases like Thalassemia and immune deficiency conditions.

How is the patient prepared?

For the donor blood stem cells to get into the patient’s bone marrow and start functioning, the patients have to be treated with high dose of chemotherapy to knock out his immune system and also to eradicate the diseased bone marrow.

What happens till the new bone marrow starts functioning?

This is a very critical period, as the patient will be left with no immunity till the new blood stem cells take over and he/she is highly susceptible to infections.

The patient has to be nursed in a very clean environment preferably in a room that can deliver filtered air so that all the micro organisms are filtered.

The patient will also require blood product support and antibiotic support. The need for a very aggressive supportive care makes blood stem cell transplantation expensive.

Can blood stem cell transplant be offered to patients in all age groups?

Till some years ago blood stem cell transplantation was offered to patients up to the fourth decade. With advances in techniques now we are able to offer blood stem cell transplantation even to elderly patients.

Can the patient’s own stem cells be used?

Yes in some situations patient’s own stem cells are collected, stored and transplanted after high dose chemotherapy treatment.

THE BENEFITS OF USING STEROID INHALERS


I often hear from my patients about someone with asthma who became very sick, was admitted in hospital in a serious condition or died. In all these situations, the commonest answer that emerged was the non-usage of the steroid inhaler (preventor).

The term "steroids" is scary to many. It has earned notoriety in sports due to various other reasons. But, in respiratory medicine, it is a widely prescribed medicine. Although heavily prescribed, they are often not used either because patients misunderstand the side effects or they don’t perceive the benefits immediately as with bronchodilators (relievers).
How it acts

Bronchodilators are used to open the airways quickly but the steroid acts slowly to bring the airways back to normal by reducing the inflammation so that the need for bronchodilators is reduced. By not using steroid inhalers, the inflammation continues unhindered resulting in piling up of mucus and swelling of the mucosa. At this stage, even if one uses a bronchodilator the effect is not perceived. If more doses are used, the benefit of bronchodilation is not perceived but toxicity starts. One of the serious side effects of reliever inhalers without steroid inhalers is sudden death due to uncontrolled asthma.

Another problem that occurs with regular use of bronchodilators without steroid inhalers is the development of fixed airway abnormalities. Simply put, the routine reliever dosage cannot open airways and a bigger dose does not mean increased benefit. At this stage even steroid inhalers would take longer to repair the airways or may fail.
Importance of inhalers

This highlights the importance of the steroid inhalers. In one study, Suissa and colleagues looked at 31,000 people between the ages of five and 44 years. Most patients used steroid inhalers. The researchers found that for every additional canister of steroid inhaler used the chances of death from asthma decreased by 21 per cent. They found a bigger effect when they looked at inhaled steroid usage in the last six months — a 54 per cent decrease in asthma deaths for every additional canister used. This was published in New England Journal of Medicine in 2000. The death rate increases significantly in the first three months if one stopped using steroid inhalers.

The message is: even in low doses steroids accrue benefits. In optimum doses not only is asthma control optimum but also serious problems ending in death can be prevented. Another reassuring aspect is the absence of side effects due to steroid inhalers. Clearly the benefits outweigh the risks.

COMPULSIVE SHOPPING


Anamika had anticipatory excitement as she stepped into the shopping mall. She had been feeling bored and lonely since the morning and couldn’t resist the urge to shop. She felt happy as she waded through some of the shops. The attention and ca re she received from the salespersons made her feel important. She bought a few clothes, a pair of studs, a watch, a handbag and some cosmetics.

The happiness lasted for the six hours that she spent at the mall. Once she returned home, she opened the cupboard to put the bags in. Inside, she saw many more unopened shopping bags staring back at her — purchases made over the past two weeks.
Preoccupation with shopping

Though not an illness, "Compulsive shopping" leads to considerable distress for the person and the family members due to financial consequences. The compulsive buyer has a frequent preoccupation with buying. He/she buys articles on an impulse, things that are not needed and are not affordable. The commonly bought items by women are clothes, accessories, jewellery, footwear and cosmetics. Men buy electronic gizmos and automobile spares. The shopping experience is pleasurable but subsequently the person feels guilty. Most of the purchased objects are not used. Some are returned or given away.

Compulsive shopping was observed about 100 years ago. Kraepelin and Bleuler (famous for describing Schizophrenia) described it and called it Oniomania. (‘Onio’ means buying). Interest in the phenomenon tapered subsequently.

Recent studies have suggested that a significant percentage of compulsive shoppers have underlying depression. The urge to shop is intensified by sadness or loneliness. The act of shopping is an attempt to feel better and it helps for a while; being pampered by the salespersons acts as a balm.

Compulsive shopping is also considered as a variant of Compulsions as in Obsessive Compulsive Disorder (OCD). The major difference is, in OCD, the urge to perform the compulsion is distressing and the person tries to control it. Compulsive shopping, on the other hand, is pleasurable. Some consider compulsive shopping an addiction. According to them, the person is vulnerable to addiction and shopping is just the context. And yes, there is a cynical view that ‘Compulsive shopping’ is another example of psychiatrists trying to medicalise any atypical human behaviour.

Compulsive shopping needs to be differentiated from the indiscriminate shopping seen in an illness called Mania. Hypomania is a milder form of mania. A person suffering from mania would be elated and the excessive happiness leads to excessive speech, activity and spending. They go on giant shopping sprees. While the motivation for shopping in mania is excessive happiness, it is sadness and boredom in compulsive shopping. Another uncommon reason for increased spending is ‘Revenge spending’ where the person splurges to deplete someone else’s reserves.
Treatment

By the time help is sought, most compulsive shoppers have huge debts on multiple credit cards and loans. Regret about the loans and anxiety about their repayment is seen. Frequent harassment by credit card "recovery teams" add to the distress. Marital discord is a consequence as the spouse tries to control the person’s buying behaviour and feels frustrated.

Treating the underlying depression, when present, has helped some to grow out of compulsive shopping. Cognitive behaviour therapy has also been used with varying results.