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dentistry Dominic Thorncroft

Composite Filling Materials Disadvantages

1.

Composites are extremely technique sensitive. The dentist’s technique must be 100% perfect otherwise the composite is likely to cause problems and fail. All dentists have seen posterior composite being placed and caries being evident sometime later. Composite is very technique sensitive and does not like any moisture at all.

This is extremely problematic for posterior teeth where there is moisture present and even from the patient’s own breath or the bleeding/crevicular fluids around the gingival margins.

2.

Most composites now are light cured and therefore have to be placed in layers in order for the light to penetrate fully to cause polymerisation setting reactions. This means that composite takes longer to place and in addition if the light does not reach the full extent or deeper layer of the cavity, this will result in unset composite. Composite which is unset will cause the body of the filling to move resulting in micro leakage and secondary dental caries.

3.

Polymerisation shrinkage is a major disadvantage of composite resin. This means that the unset material occupies a larger volume than the polymerised set material. This then results in a gap between the filling material and the cavity walls. This causes bacteria to get in there and cause secondary or recurrent caries.

In addition the gap picks up stains and every dentist has seen a brown line along the margins of a composite restoration. This is worse in avid smokers although also in people who have strong tea and coffee or red wine habits. Polymerisation shrinkage can also cause physical stress inside the cavity/restoration interface. 

One of the ways in which polymerisation shrinkage effects can be reduced is to place the composite in layers. It is important however to understand that the amount of polymerisation shrinkage is the same whether the composite is light cured or whether it is chemically cured.

The difference is the manner in which the polymerisation shrinkage occurs. When composite is light cured, the polymerisation shrinkage occurs very rapidly but in chemically cured composite, the polymerisation shrinkage occurs more gradually. This is relevant when considering how the composite is to be bonded onto the enamel and dentine.

As composite does not have the inherent ability to bond chemically onto enamel or dentine, it is necessary to use extra steps for bonding. However, if the polymerisation shrinkage is too rapid, this can cause breakage of the bond or it can cause the composite to pull on the walls of the cavity. If the bond breaks, this leads to micro leakage but if the bond does not break, the pulling effect can even cause cracks within the enamel.

Patients will often come back to the dentist after a composite filling material has been used complaining of pain. One way to reduce the polymerisation shrinkage is to have good enamel and dentine bonding but also to cure/set the composite in layers rather than in one go. Newer composites have been formulated to have a reduced polymerisation shrinkage change which helps reduce microleakage.

4.

Composite is nowhere near in getting a good contact point as amalgam. This is extremely important in class II cavities where a good contact point is required. However, modern posterior composite filling materials have fairly good contact ability but even so, a wedge is needed in conjunction with a clear matrix band.

The earlier composites were too stiff but difficult to pack and manipulate in order to meet this demand or they were too soft making them easier to pack and manipulate but difficult to press hard against the matrix band.

5.

Composite does not inherently bond onto enamel or dentine and therefore extra steps are required for this to occur. There are two separate phenomena occurring here. Firstly, enamel bonding occurs by etching the enamel with 37% phosphoric acid for 20 seconds.

This acts on the enamel prisms and causes differential dissolving resulting in a roughened surface which acts to give micro mechanical retention. Dentine bonding is slightly different in that the acid attacks the mineral component of the dentinal tubules. Dentine is 70% mineral and 30% organic. This then causes a collagen mesh to remain and resin will then flow into the collagen mesh.

This is a form of micro mechanical retention. However, drilling into a tooth causes crushed hydroxyapatite debris and this is known as the smear layer which must be removed prior to etching and bonding. Creation of the smear layer prevents the usage of resin-tags. 

Fortunately, bonding systems have dramatically transformed and now, one step bonding systems exist which etch both enamel and dentine, remove the smear layer and create micro mechanical retention simultaneously. Older dentists will remember the original systems which used 8 or 9 separate steps with lots of potential for errors at any point.

6.

Composites according to the specific brand can sometimes can be difficult to discern on the radiographs due to their radiopacity similar to dentine and this can be a disadvantage when trying to assess for secondary or recurrent caries.

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dentistry Dominic Thorncroft

What Is Atypical Facial Pain?

Atypical Facial Pain

‘Atypical’ pain is a diagnosis of exclusion after other similar conditions have been investigated and eliminated, hence the reason why it is diagnosed late in the day at frustration for many patients.

But it is idiopathic and is characterized by chronic, constant pain without any apparent cause in the face or brain.

Cause

Atypical odontalgia or phantom tooth pain is a variation of atypical facial pain where intense discomfort is associated with a particular tooth or group of teeth with no obvious dental cause on examination, special tests or on a radiograph.

Atypical facial pain syndrome is more common in women than in men with most patients aged between 30 and 50 years. The most commonly affected area is the maxillary region although any area of the face can be involved.

Clinical presentation of Atypical Facial Pain is very variable in its presentation but mostly described by a continuous, daily pain of variable intensity with no cause. Typically, the pain is deep ( unlike trigeminal neuralgia) and poorly localized and is described as dull and aching. It does not awaken the patient from sleep.

Characteristics

At initial onset the pain may be confined to a limited area on one side of the face, while later in the day, it may spread to involve a larger area.

Atypical odontalgia is characterized also by a continuous, dull, aching pain of moderate intensity in apparently normal teeth or endodontically treated teeth and occasionally after an extraction or post-extraction sites. 

Atypical odontalgia is a variation localised to a tooth. It is not usually affected by testing the tooth with cold, heat or electric stimuli. Moreover, the toothache frequently remains unchanged for months or years hence the differentiation of atypical odontalgia from pulpal/periodontal origin dental pain.

Treatment

Many a dentist will end up extracting the tooth but the pain remains in the underlying alveolar ridge. Occasionally, the pain may spread to adjacent teeth, especially after extraction of the painful tooth or after an unnecessary extraction.

The lack of a demonstrable organic/physical cause will cause a high level of anxiety and depression among these patients. Often, they will see multiple dentists and become increasingly disillusioned by the advice received.

Genetic factors could be important in some patients with chronic facial pain as their nerves are susceptible to damage from minor insults that would not normally produce chronic pain and this can be seen in patients where this type of pain follows a successful minor/easy procedure such as a tooth extraction.

There are no specific tests that can confirm the diagnosis of idiopathic/atypical facial pain and is based on not finding any other cause.

Treatment of Atypical or Idiopathic facial pain is managed by a variety of ways including medication, psychological treatments and physical treatments such as acupuncture or TENS nerve stimulation.

But many of these patients have a poor response to all treatment options and will do the rounds having had consultations with a lot of specialists, multiple ineffective alternative therapy treatments, and even surgical explorations at considerable costs and considerable stress to their partners/family. 

As mainstream treatments can be ineffective a different approach is to accept the pain but try to improve patients quality of life as well as trying to ease some of the pain often with an increase in mood, activity and social contact. Analgesics will not work for atypical facial pain.

Pain relief is mainly through the use of tricyclic antidepressant and anti-epileptic drugs intended normally for use in the treatment of depression or epilepsy but have proved very helpful in these patients. 

The tricyclic antidepressants such as amitriptyline and nortriptyline are often generally helpful in both reducing pain experience and improving mood and coping with the associated depression including some placebo effect that something is being done.

Interestingly, newer antidepressant drugs such as fluoxetine and paroxetine seem less effective. 

However, the newer antiepileptic medications such as gabapentin and valproate are very successful also in treating neuropathic pain.

 Education, physical therapy, psychological/CBT/NLP counselling, and alternative pain management strategies, such as acupuncture and TENS/biofeedback, may also be useful in holistic patient care. Surgical procedures are rarely effective and can aggravate the condition and may lead to a painful permanent disabling facial numbness.

Atypical odontalgia patients may undergo many unsuccessful unnecessary dental procedures before the correct diagnosis is made. Once the diagnosis is made, dental treatment aimed to relieve the pain is not advised since it can result in further deterioration of the patient’s dentition without any beneficial effect on the pain.

Gabapentin combined with tricyclic antidepressants can make the extremes of the pain less severe but must be used continuously and not only during an acutely painful episode.

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dentistry Dominic Thorncroft

Broken Tooth Pain

Pain from a broken tooth can be extremely painful and distressing. When you initially break a tooth, you may not always get any symptoms and symptoms may only appear some time afterwards.

Conversely, a broken tooth can cause pain and sensitivity immediately and this can become worse within a short period of time.

Reasons

The reason why the tooth has broken in the first place is important because it could be that there was already decay and causing the tooth to break suddenly.

Sometimes a tooth breaks simply because you bit on something very hard or the tooth was already weak and this subsequently goes on to become decayed.

A tooth which is broken is more likely to become decayed for two reasons. Firstly, if the enamel has been breached causing the underlying dentine to be exposed. We know that dentine is not as strong as enamel and therefore it is more likely to succumb to decay.

In addition, a broken tooth is more difficult to clean and the toothbrush will not be able to sufficiently remove food debris and plaque that builds up. This then accelerates the rate of decay within that tooth.

Treatment

Whether you have mild sensitivity or more serious pain, it is important to get this treated by your regular dentist or an emergency dentist.

There are a number of treatments that can be done as an emergency in this situation. If the tooth has no decay or very little decay, it may be that the emergency treatment consists of placing a temporary filling with a view to having it filled permanently as soon as possible.

It may be that the tooth has now become infected and the pulp or the nerve of the tooth needs to be cleaned out. At a later date, the tooth will therefore need a root canal treatment or in worst-case scenarios an extraction.

Whilst you are waiting to see a dentist, you will need to take some painkillers and a combination of paracetamol and ibuprofen which work  the best. You should also carry on cleaning inside the cavity as best as you can to clean out food debris that is packing in and to keep it free of plaque.

In conclusion, a broken tooth should not be ignored and even if it is not painful, you should ask a dentist to examine the tooth as soon as possible.

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dentistry Dominic Thorncroft

Are Dentists Trained To Do Hygienist Work?

A dentist is trained to do any work that a hygienist, therapist, or a dental technician can carry out. Probably most dentists carry out their own hygienist work but increasingly they are practices which use hygienists specifically for that role.

Dental Hygiene

The main roles that a hygienist performs in dentistry is the prevention and treatment of gum disease. However, advanced gum disease requires more extensive and complex treatment – a dentist must carry these treatments out. Most hygienists work under the prescription and guidance of a dentist.

A patient will first be examined by a dentist and then a dentist may decide to refer the treatment to a hygienist. The dentist will outline a reason for the referral and what treatment he expects the dental hygienists to carry out. Subsequently, after completing the patient treatment, will ask the patient to go back to the dentist. Either the dentist or hygienist will then monitor the patient’s periodontal or gum health. 

In most cases, will work together with the dentist to improve the patients oral and gum health.

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dentistry Dominic Thorncroft

Is There a Way For Dental Students To Improve Their Handwork?

It goes without saying that dentistry is a practical profession and a certain level of manual dexterity is required. This is not surprising, and therefore most dental school admissions and interviews from the candidates test the manual dexterity.

The candidate can be asked to make a replica tooth model or carry out a carving of a tooth in wax. Not everyone has the same required level of manual dexterity and if you have two left hands then you probably should not be going into dentistry as a profession.

There are, however, many different ways in which you can improve your handy work as a dental student. There is no one method however you have to choose something that you will enjoy and most likely carry on doing in order to improve your manual dexterity. Making carvings out of soap or wood is extremely effective in improving your handiwork.

Some students carry out origami and that is also another way to improve your manual dexterity. Any art related or craft related activity will be useful in this respect.

The improvement of your manual dexterity must be commenced at the beginning of the first year of your dental course even though you will not be seeing patients for at least a year and a half afterwards and this is because manual dexterity is not something you can build up on overnight but it takes many hours and days to accomplish.

All dental students should actively seek to improve their handi- work at an early stage and there are many ways in which you can do that as outlined above.

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dentistry Dominic Thorncroft

Bone Grafting For Dental Implants Cost

Bone Grafting

The cost for having dental bone graft implant treatment varies hugely because it depends on the following three factors.

  1. The exact type of bone grafting required. The exact type is categorised into four different areas. This depends on the source of the bone graft material. The four different types are autograft, allograft, xenograft and alloplastic graft. The autograft is considered to be the ideal and best because it comes from the patient’s own source.

There is no risk of rejection or cross infection. However, autografts are much more technique sensitive and demand a high level of skill from the surgeon. They also therefore subject the patient to another surgical operation which has complications in itself and this also means more pain and swelling afterwards.

The allograft is of human origin but not from the patient himself. It is a bone graft that is therefore sourced from another human being. Some patients just do not like the idea of having somebody else’s “body parts “inserted into their own. In any case, the protein has been denatured so there are no risks with cross infection.

The xenograft is born from a pig or cow. Many patients due to religious or moral reasons do not feel comfortable in having a bone graft from the porcine or bovine source.

The alloplastic bone graft is synthetic bone. Although it is convenient, many dentists do not feel it is as good as natural bone.

  1. The second important factor to consider is the area which requires bone grafting. It goes without saying that the larger the area that needs to be grafted, the more extensive the surgery and therefore the cost will also be increased.
  1. The final important factor is the surgeon’s own individual premium. A general dentist will cost far less than a specialised surgeon. Also, if you are going to a dentist not in the city centre and in a less expensive area, the cost will also be reflected.

Costs

However, just to give a general indication of costs, here are typical guidelines of bone graft surgery.

Having a bone graft placed at the same time a tooth is taken out, will cost in the region of £250 extra.

Having a bone graft placed at the same time an implant is put in, will cost in the region of £400-£1000 extra per implant.

For multiple implants, the cost will probably be proportionally less per implant site.

For maxillary sinus lift augmentation and block grafts, the cost will range from £1000 to £2000 thousand pounds extra.

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dentistry Dominic Thorncroft

How A Dentist Can Recognise Dental Erosion

Here are three photographs taken from patients diagnosed as suffering from dental erosion.

Picture Number 1

Picture Number 1

This picture shows a porcelain fused to metal crown on the upper right 2 tooth. Although the crown appears longer than the other teeth, it in fact is and was the correct length. It looks too long because the adjacent teeth have become shorter due to acid erosion effects. Going into more detail we can report on the following.

Incisal edges of the upper left 1 tooth and the upper right 1 tooth surfaces appear grey. This grey appearance is commonly characteristic of enamel tooth substance loss. As that enamel thins down, the incisal edges which are already partially translucent and when the thickness of enamel decreases, the translucency increases and the reason for the appearance of the incisors looking grey.

The surfaces of the upper left 1 tooth and the upper right 1 tooth appear yellow. This is because the overlying enamel has become fine due to tooth erosion. From the thinner layer of overlying enamel, the dentine becomes more apparent and we know that dentine has a distinct yellow colour.

This explains why both of those two teeth appear more yellow. Looking at the upper left 1 tooth, on the buccal surface near the cervical margin, there is no enamel left at all. Furthermore, this exposes the softer dentine which is then more susceptible to abrasion and dental caries. The lower central incisors have chipped due to loss of enamel structure.

Picture Number 2

Picture Number 2

This is a picture of a patient’s anterior teeth. It is a younger patient of 16 years age. This picture shows that all four conditions are present as dental erosion, attrition abrasion, dental caries and periodontal disease.

Caries: There are extensive dental caries in the upper left 1 tooth mesially. The dental caries have infiltrated the dental pulp and a pulp polyp is now apparent. Needless to say, this tooth is non vital. The adjacent upper right one has secondary caries under and around the buccal composite restoration.

The upper right 2 tooth has buccal caries around the cervical margin. There is also a front of demineralised enamel which has a white chalky appearance. The upper left 2 has secondary or recurrent caries around the restoration. Finally, there is marginal gingivitis due to a lack of inadequate oral hygiene measures.

The patient was drinking 5 to 6 cans of Coca-Cola every single day. He would sit down on his gaming computer and sip coca cola continuously. Both his parents would be away at work and without any cooked meals he would just rely on snacks such as Mars bars and Milky way’s.

This trend contributed to his dental caries. He would play on his gaming computer until 4am in the morning and needless to say, he’d want to just go straight to bed as he could not be bothered to brush his teeth. In the morning, or rather in the afternoon, he would get up and give his teeth a 10-second brush and look for snacks for his breakfast.

Sometimes during the day when his parents were out, one of his friends would come around with amphetamines and this also contributed to him grinding his teeth causing further damage to his teeth.

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dentistry Dominic Thorncroft

Dental Characteristics Of The Mandibular Lateral Incisor

The mandibular lateral incisor is a little larger in all dimensions than the mandibular central incisor in the same mouth. The crown of the mandibular lateral incisor resembles that of the mandibular central incisor, but it is not as bilaterally symmetrical. The distal outline is rounded compared to a flatter mesial crown outline.

The crown of the lateral incisor is tilted distally on the root, giving the impression that the tooth has been bent at the cervix. The distoincisal angle is noticeably more rounded than the mesioincisal angle.

On periapical radiographs, the curve of the root appears as a “distortion” and inexperienced practitioners think that the film has been bent when it actually has not and they will reattempt the radiograph only to get the same image. 

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dentistry Dominic Thorncroft

Advantages And Disadvantages Of Dental Crowns

A dental crown is an example of an extra coronal restoration. The vast majority are indirect for which you require an imprint or impression to be taken prior to construction of the crown. Dental crowns can be classified in different ways but generally according to their use, their aesthetics and the material.

Posterior crowns on premolars and molars need to be strong enough to withstand biting forces; however , anterior crowns require superior aesthetics. Crowns can be divided into their coverage such as full coverage crowns, three-quarter crowns and inlays/onlays. 

The earliest crowns for posterior teeth were full gold crowns and porcelain jacket crowns for interiors. The porcelain jacket crown for anterior teeth was not strong enough sometimes so an alumina core was placed but this resulted in a compromise to  appearance. Eventually, this underlying core was made out of metal resulting in porcelain fused to metal crowns.

All-ceramic crowns nowadays are strong enough to use in most posterior situations and the aesthetics are more superior to traditional porcelain fused to metal crowns.

Here Are The Advantages Of Dental Crowns

  1. In order to provide protection for the tooth. A tooth which has been ravaged by extensive dental caries or has a large restoration which is failing, needs extra-coronal protection.

A crown is able to provide this protection so that the tooth will last longer against functional occlusal forces. In addition, if a tooth has been root-treated, it needs extra protection because as a rule, root-treated teeth are generally weaker than teeth which have not been root- treated. This is for two reasons. Firstly, without dental pulps, there are no odontoblasts to produce dentinal fluid so dentine loses its moisture content and becomes more brittle. 

Secondly, the teeth that need to have root canal treatment will usually have been extensively weakened by the restoration after removal of dental caries. With crowns, teeth can even be saved when there is very little coronal tooth structure left. Extra retention may be necessary such as a dentine and bonding agent, dentine pins and root posts.

  1. The crown can provide superior aesthetic results compared to a large composite filling. Some patients may even ask for a crown on a premolar or molar tooth where the existing filling such as amalgam is causing concern with regards to their appearance.

Dental Crowns Do Have Disadvantages And It Is Important To Know About These Before You Embark On This Course Of Treatment

  1. It is important to know that 20% to 30% of all vital teeth which are crowned will become non-vital and need root canal treatment in the future. This is because a tooth which needs a crown, will at some point have had extensive caries and extensive restorations.

Although the dental pulp does have remarkable regenerative qualities, nevertheless, caries and dental treatment does produce significant stress and the dental pulp then not be able to recover adequately. The stress produced may be a one off sudden stress such as having a deep filling or a large restoration or it could be due to repeated restorative treatment. Sometimes, it is the preparation which also produces stress on the tooth which is the last straw that breaks the camel’s back.

When a tooth which is a crown then requires a root canal treatment, this is usually carried out through the existing crown structure. This has disadvantages. It is more difficult to carry out a root canal through an existing crown as compared to a tooth without a crown on. This is because a dentist has to drill through the crown structure first and also estimate where the dental pulp is. The other disadvantage relates to appearance and structural integrity.

Where the access cavity has been made, it then has to be sealed up using a material such as composite or glass ionomer. The restoration into the access cavity is easy to spot especially if it is on the occlusal surface.

In addition, the procedure of carrying out the root canal treatment will have weakened the tooth and the tooth is more likely to fracture unless the underlying tooth core is reinforced further.

  1. A crown is most susceptible at its margins. Ideally, the marginal gap must be microscopic and is usually filled in with the luting cement.

If the gap is large and the cement washes away, this creates a gap where dental caries can develop or produce sensitivity. The luting cement is also vulnerable especially if moisture was present during the cementation stage of the crown.

  1. A crown takes two visits to make whereas a filling can be done in one visit. Each appointment in addition will be a long appointment so quite considerable time is spent making a crown for a patient as compared to a normal filling. In addition, problems can arise between visits while the crown is being constructed in the dental laboratory.

For instance, the temporary crown can come off and cause irreversible pulpal damage or sensitivity effects. If the temporary crown comes off and is not put back on immediately, this can result in movement of the adjacent teeth through mesial drift of opposing teeth or from over eruption. Even worse, the crown margins cannot be maintained if the gingiva grows over the margins.

  1. Dental x-rays can have limited value in assessing caries under a crown. The best way to assess a crown is by probing with good direct vision and to check the proximal margins with the bite wing radiographs. Unfortunately, often when caries are spotted on the radiographs, it becomes too late to save the tooth. At the very least, additional root canal treatment becomes necessary.
  1. The cost of the dental crown is approximately five times that of an equivalent filling. This means that you could have 5 fillings before you get up to the cost of a dental crown.

There is another important factor to also consider and that is that over a lifetime, a dental crown will need to be replaced every 10 – 15 years. This is partly offset by a filling requiring replacement every 5 – 15 years but nevertheless the difference is significant.

Before having a dental crown, patients should sit down with a dentist and have a thorough assessment and discussion with regards to all treatment options and if that indeed is the best treatment available.

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dentistry Dominic Thorncroft

Different Types Of Removable Partial Denture

Denture Removal

The removable partial denture is the most common method that dentists use to replace a missing tooth or teeth. Many millions of removable partial dentures are made for patients in Europe every single year.

The other two methods of replacing a missing tooth or missing teeth are dental Bridges and dental implants but they both have disadvantages.

The construction of fixed dental bridge work requires extensive tooth preparation to be carried out  to the teeth adjacent to the gap and we know from long-term studies that 20 to 30% of all abutment teeth will become non-vital and need future root canal treatment which is not an ideal situation.

On the other hand, dental implants are much more costly and complications can also arise such as implant failure due to non-osseointegration.

 The main types of removable partial dentures are as follows:

1.  The acrylic removable partial denture.

2.  The Cobalt -Chrome based removable partial denture.

3.  Removable partial dentures using thermoplastic resin and these are termed “flexible dentures.”

The Removable Acrylic Partial Denture

This is by far the most common out of the three different types of removable partial dentures that dentists can use. One of the main reasons for their popularity is that they have the least cost associated with them. They are therefore ideal for patients who can only afford the minimum.

Another advantage of the acrylic denture is that you can be added further teeth onto it. This is especially useful because many patients will have periodontal disease or dental caries and will require further extractions in the future. In this respect, immediate additions can be utilised without making a brand new denture each time for the patient.

Acrylic dentures are also good at replacing lost alveolar bone tissue loss which is important for aesthetics.

However acrylic dentures do have several significant disadvantages.

Personally, not all patients are able to tolerate wearing acrylic dentures. With the lower denture, this may encroach on the tongue and on upper dentures, it may activate the patient’s gag reflex. Acrylic dentures also reduce the pleasure of eating as a large amount of oral mucosa is covered.

Acrylic dentures may also need stainless steel wire clasps for increased retention and this may be in the aesthetic zone when the patient smiles, causing problems.

Probably the biggest disadvantage of acrylic partial denture is that they are entirely tissue-borne. This means that the oral mucosa takes all of the loading which may increase alveolar bone resorption and also cause trauma to the gingival tissues of teeth especially if patients do not have good oral hygiene which will increase periodontal disease and further tooth loss.

The Cobalt Chrome Based Partial Denture

This is the next most often used removable partial denture but only about 5% of dentures are this type.

The main reason being due to the cost of a Cobalt Chrome based denture as compared to the acrylic denture. An acrylic denture may cost €200 but a cobalt chrome denture will easily cost more than €1,500.

However, the cobalt Chrome-based denture has a very significant advantage compared to the acrylic denture in that it is both tissue borne and tooth borne. Occlusal rest seats are used on the patient’s remaining teeth which helps to distribute the loading away from the oral mucosa and gingival tissues. Less bone resorption will occur.

The other big advantage is that a cobalt chrome denture is much stronger and therefore ideal for patients who are always breaking their acrylic dentures. As a result of being stronger, less oral mucosa needs to be covered which makes them more easy for patients to tolerate. In fact on an upper denture,  most of the palate does not even need to be covered.

But one of the reasons why cobalt chrome dentures are not used that often apart from the cost is that they are nearly impossible to add further teeth onto  without making a new denture altogether. The acrylic denture is fairly easy to add-on but not with a chrome denture. 

Because the cobalt chrome denture also uses clasps for retention, this is generally an advantage as long as it does not encroach in the patients aesthetic zone on those especially who have a high lip line.

The Flexible Resin Removable Partial Denture

These are the least common types of partial denture but are increasing in popularity.

The main advantages are that they are flexible and therefore they can engage small undercuts to increase retention without using clasps.

In addition, due to their flexible nature they are more resistant to fracture and deformation so can be used in thinner sections. This makes it easier for patients to wear and tolerate.

However they have several disadvantages with one of them being the cost. They cost much more than the acrylic denture and will cost at least €1,000 each.

The other big disadvantage is that they cannot be used to “add-onto” if the patient loses further teeth. This means that if the patient loses a tooth later on down the line, they will have to have a brand-new denture at further cost. 

Flexible resin dentures also are difficult to adjust and pick up a lot of stains which patients may not like.

Conclusion

In conclusion, the removable partial denture is the most common method of replacing missing teeth and there are different designs and types available.