Welcome to Dr Antony George's Website

My Homepage

CONTENTS
What is tooth decay?
What are the causes for tooth decay?
How can tooth decay be prevented?
What are the cures for dental carries?
What is an Amalgam filling?
What is a Composite filling?
What is Root Canal Treatment [RCT]?
What is a Crown?
What is an Inlay?

What is tooth decay?
             Tooth decay is a common dental ailment affecting humans. It can occur at any age. The first sign of a cavity formation may be a white spot on the tooth, which in time may turn brown or black. When it is a white spot, low concentrations of fluoride applied frequently can arrest further development. Otherwise further destruction of the outer enamel results in a small cavity. During this period you would experience food impaction in or between the teeth and sensitivity to extreme temperatures and to sweets. Plaque, a sticky almost invisible film of bacteria that is constantly forming on your teeth turns the food particles into acid, which attack the tooth enamel further. With repeated acid attacks a large cavity is formed. If the cavity is not treated at the dentine stage, the decay spreads deeper into the pulp and cause toothache. Sometimes the infection spreads into the bone through the root tips and forms a gumboil [periapical infection].
A form of tooth decay affecting the nursing infants is called “Nursing carries” or “Baby Bottle Syndrome” or “Rampant Carries”. In infants who are nursed continuously with a bottle or pacifiers, the milk is retained in the mouth as the child sleeps. This milk is an excellent nutritive media for a variety of bacteria's, which breaks down the milk into acids. These acids attack the enamel of the milk teeth and produce carious cavities. Almost all the milk teeth are affected leaving only the lower anteriors. The carious lesion spreads rapidly and cause destruction of all the tooth substance leaving behind  the root stumps. Luckily the permanent teeth are not affected.

What are the causes for tooth decay?
Poor oral hygiene is the main cause for tooth decay. Plaque is the biggest villain behind both tooth decay and gum diseases. Plaque is a sticky, almost invisible, whitish yellow, thin film of bacteria that constantly forms on your teeth. If proper oral hygiene is not maintained by regular brushing then this plaque combines with sucrose (sugar) present in the food particles you eat to produce acids that cause demineralization of enamel (outermost layer of tooth). Repeated attacks by the bacteria (Streptococcus mutans, Lactobacillus, etc) results in cavity. Our body cannot replace tooth enamel once it has been destroyed by carious lesions.
Unregulated diet of sweet foods and drinks. Do not give into the temptation of frequent snacking. Avoid sweets and sticky foods between meals. Bacteria's love sugar and converts such foods into acids, which attack the tooth enamel to produce cavities. The actual amount of sugar eaten in one sitting is not as important as when and how often you choose to eat a sugar containing food. Longer the time the food stays on your teeth, the greater is the chance of forming a cavity.
Genetics may play a major role in how susceptible you are to the formation of a cavity. The structure, size and shape of the tooth may be passed down through generations. This includes deep pits and grooves which are ideal "plaque traps", and therefore are susceptible to decay. A familial history of high incidence of dental caries has shown to produce decreased resistance to carious attack.
Improper calcification and mineralisation. Expectant mothers must be particularly careful about their diet as the foundation of a child's teeth occurs by 6^th week intrauterine. Calcification of milk teeth starts by the 6^th month (second trimester). Any chronic disease during the development period of the teeth will affect the proper mineralisation of the teeth, resulting in defective enamel or dentine formation.
Saliva has a protective function in the mouth. A good flow of saliva washes away food and bacteria that sits on the teeth and gum tissues. Salivary flow helps to neutralize the acids produced by bacteria from plaque. Thus a good salivary flow, reduce the chances of  cavity formation.
Gum diseases. Infection of the gums causes the gingiva to detach or recede from the teeth exposing the roots to root carries. It also causes interdental spacing and periodontal pockets due to destruction of gingival tissues resulting in food impaction.
Food impaction between teeth results in bacterial growth and production of acids and cavities between the teeth.
Supernumerary or impacted teeth. Extra teeth that erupt out of the arch cause food lodgement between the teeth causing carious lesion of the good teeth. Wisdom teeth usually get impacted (do not erupt) because of lack of space in the jaws to erupt properly. This results in debris and food retention causing decay of the wisdom teeth as well as the adjusant tooth.
Misaligned or irregularly placed teeth. Irregularly placed teeth cause plaque deposition which results in decay if proper brushing technique is not followed.
Baby Bottle Syndrome. The residual milk in the mouth of infants, who are put to sleep with the bottle, is an excellent nutritive media for the bacteria's causing carious lesions. The carious lesion spreads rapidly and all the milk teeth are affected leaving only the lower anteriors unaffected.

How can tooth decay be prevented?
Certain simple preventive measures can prevent tooth decay. You must follow the Six Golden Rules for good dental health. Maintain proper oral hygiene by following the correct Brushing and Flossing technique.
Follow the links to another of my webpage to understand more.
Fluoride provides many benefits. It aids in the development of sound enamel. It helps reduce enamel solubility and increases enamel resistance to acid attack. It prevents demineralization of enamel. It enhances remineralization at the beginning stages of a cavity and may arrest further development of a cavity by depositing the fluoride mineral called fluoroapatite. Fluoride used in addition to daily brushing and flossing helps to reduce the chances of a cavity.

What are the cures for dental carries?
             Prevention is always better than cure. A cavity should be filled at the earliest before it can cause any major damage. If you develop any blackened spots on your teeth or if it gets sensitive to sweets and to temperature changes, then it is likely that you are in the first stages of tooth decay. Once a small cavity is formed then food particles gets collected in them resulting in a bigger cavity due to undermining of the tooth enamel. The tooth should be restored immediately with a filling material after the entire carious lesion has been removed.
There are many types of filling materials, but for permanent fillings, two commonly used filling materials are --- Amalgam and Composite.

What is an Amalgam filling?
             Silver Amalgam is the oldest filling material know to man. It is an alloy of silver, tin, mercury, copper and zinc.  Silver amalgam is most commonly used for fillings on the back teeth, where strength is of utmost importance and the silver color is relatively inconspicuous. Silver amalgam is relatively inexpensive and lasts an average of 14 years. The filling takes almost two weeks to become fully hardened, but you may safely chew on it after twenty-four hours. Your teeth may experience some degree of temperature sensitivity for a few days to a week, if the carious lesion is deep. If the sensitivity does not disappear in a long while, or it is more serious, you might require RCT.
            Some people are concerned about the toxicity of the mercury used in the filling. But in fact, amalgam has been used successively for many many years in dentistry and has been tested continuously. There is no evidence showing that it is hazardous to human. Since amalgam has dark metal color, the filling is not esthetically pleasing, this is its only disadvantage. Until recently, it was the only choice of  dental filling material.

What is a Composite filling?
            Composite resins are mainly used in the front teeth, where a silver filling would be conspicuous. Thanks to advances in modern dental materials and techniques, teeth can now be restored with more aesthetic and natural appearing filling materials. There are different types of cosmetic fillings currently available. The type used will depend on the location of the tooth and the amount of tooth structure that needs to be repaired. Increasingly, these fillings are now also being used on the back teeth. Although they have the advantage of being the color of the teeth they are more expensive than silver amalgam and may not last as long.
             It is made up of a composite quartz resin and contains a light sensitive agent. These materials come in a variety of shades so that they will match the color of your own teeth. Composite materials are now available that have been specifically designed to withstand the incredible forces you can exert when chewing on your back teeth.
            In order to bond a filling material to your tooth it is first necessary to remove decay, prepare the tooth and then to condition the enamel and dentin. Once conditioned, a thin resin is applied which bonds to the etched surface. The bond strength of these fillings are incredible. After placement, composites are hardened by shining an intense light (ultraviolet) on them for a specified period of time, usually around 40 seconds. The light instantly hardens these fillings. You can eat right away because the composite is instantly hardened and requires no setting time.
           Glass ionomer, a tooth-colored filling, is formulated to release fluoride once in place, a benefit for people prone to decay at the gum line. Glass ionomer is also used to restore areas damaged by overzealous brushing.

What is Root Canal Treatment [RCT]?
If the tooth decays and is not attended to in time the decay spreads deeper into the pulpal tissues (innermost part of the tooth) and cause pain. The tooth aches when tapped. Such a tooth can be saved only by RCT. Root Canal Treatment is the removal of the infected pulpal tissues and filling the root canals with adequate root filling material. This way the dentist saves the tooth from the jaws of defeat and restores the tooth to its normal function. If no treatment is carried out even at this stage then there will be gross destruction of tooth structure and the tooth will be beyond repair. Such tooth will have to be removed.
Clinical Procedures:
The area around the tooth is made nub by injecting a local anesthesia into the surrounding tissues. A dental drill is used to remove the decayed part of the tooth. An access cavity is prepared to reach the root canals. The damaged pulp is completely removed with the help of special root canal instruments. The walls of the canals are prepared with the help of files and reamers (RCT instruments). The canals are cleaned and irrigated with medicaments to make it  free from debris. It may take two to three sittings with the dentist to make the canal dry and totally free from infection. The front teeth usually have only one canal while the back teeth have 2 to 4 canals. The canals are filled with special root canal sealants and filling materials (Gutta-percha). The decayed portion of the tooth is  filled with a permanent filling material. Later a crown is made over the tooth to protect the tooth from breaking off.
                Sometimes the infection may spread to the tip of the root and cause accumulation of pus at the root apex. The infection may break open the bone wall and drain out into the oral cavity, resulting in an abscess (gumboil). In such cases the gums may have to be repaired by doing a minor surgery to remove the infection at the root tip. This is referred to as Apecectomy. In six to eight weeks the tip of the root heals and the tooth becomes as good as a normal tooth.

What is a Crown?
           A crown is placed over a tooth, to protect the tooth structure from further destruction. Once gross decay of tooth structure has occurred it may not be feasible to do a normal tooth filling, as there will not be adequate tooth structure to retain the filling. A RCT treated tooth is usually protected with a crown, because during RCT the vital structure of the tooth (pulp) is removed, making the tooth brittle and liable to fracture. A crown may also be used to restore fractured teeth, or cover badly shaped or discoloured teeth. Thus a crown is a restoration that covers or "caps" a tooth to restore it to its normal shape and size, strengthening, and improving the appearance of a tooth. Crown is also used during bridge (FPD) placement, dental implants, and sometimes to achieve parallelism of the teeth during castmetal RPD insertion.
          To prepare the tooth for a crown the thickness of the crown (about 1.5 - 2 mm) is reduced from the tooth so the crown can fit over it. An impression of the teeth and gums are made and sent  to the Dental Lab for the crown fabrication. A temporary crown maybe fitted over the prepared tooth until the permanent crown is ready. On the next visit, the dentist removes the temporary crown and cements the permanent crown onto the tooth with the help of dental cements. Sometimes a trial fit in of the crown is done. To achieve a natural appearance a number of factors are considered, such as the colour, bite, shape, and length of your natural teeth. Any one of these factors can affect your appearance.
          A crown maybe prepared from castmetal or porcelain. A porcelain crown is more aesthetic than castmetal, for it has the colour and translucency of the natural tooth. A tooth coloured acrylic facing is usually made on the castmetal crown for aesthetic reasons, but this undergoes abrasion, discolouration and material decay over a period of time and so will usually require refacing after 2 - 3 years. A porcelain crown is superior to a castmetal crown, as it does not undergo abrasion or discolouration. To prevent damaging or fracturing the crown it is better to avoid chewing hard foods or other hard objects, and teeth grinding. A crown can fracture like your own natural teeth. Proper brushing with regular toothbrush, proxibrushes, dental floss, etc is a must after crown fixation. Extra care and time should be given for maintenance and the cleanliness (hygiene) of the mouth.

What is an Inlay?
There are two types of indirect fillings: Inlay and Onlay.
             Inlays are recommended for the lesion that are small and only involves the chewing surface and the surface between the teeth. The surfaces on the lip side and tongue side should be intact with no decay. Inlays can be made from composite resin, porcelain, or gold. Damaged tooth is cleaned and prepared by the dentist. Impression is made of the mouth, and sent to a dental lab. An inlay is fabricated on the positive tooth model. On your next visit the dentist inserts and cements it onto your tooth. An inlay is more conservative than a crown because it requires less removal of tooth structure.
             An onlay is similar to an inlay but is extended to cover the entire chewing surface, protecting cusps from fracture.