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Showing posts from March, 2016

Can every tooth be crowned?

Posterior root filled teeth are often crowned due to their increased susceptibility for catastrophic fracture. Loss of tooth structure and increased brittleness of the tooth often results in cuspal fracture with the fulcrum line at the base of the pulp chamber often resulting in an unrestorable defect. But can every root filled tooth be/should be crowned? It is important to case select before rushing in to add a crown to a patient's mouth. Minimal tooth structure may require a post and core before crowning. Short clinical crowns (as I have discovered) will pose difficulties for crown preparation. Once the occlusal reduction has occurred for the chosen material, the height of the residual prep may not be sufficient for retention. ALWAYS look at the dimensions and remaining tooth structure before proceeding to crown teeth

Product recommendations

On the first encounter with the patient you can find a problem that stands out as their biggest be it caries, periodontal or tooth wear. A product can then be recommended as an intervention with or without operative intervention. Oral health promotion is key as the patient is in charge of their own oral health and it is impossible for the dentist to be constantly watching for problems to arise. Prevention is the best cure. High caries risk: -High fluoride toothpaste: Neutrafluor 5000 plus toothpaste -Fluoride Mouthrinse: Neutrafluor 220/900 -Duraphat 22000ppm topical application -Neutrafluor 9000 gel (Dentist only) application. Can provide a bleaching tray with a syringe for pt home use Poor oral hygiene: Periodontal disease/Caries -Short term use of a chlorhexidine product (up to 2 weeks)   Chlorofluor gel (CHX with fluoride)   Savacol mouthrinse   Curasept gel - CPC products   Cepacol   Colgate plax -Listerine (Essential oils)- a...

Composite shaping- Light cure

Light curing of 20 seconds is necessary for complete cure of most composite brands (for a certain increment) However, if your last composite increment (shaping the occlusal anatomy) a soft cure of ~5 seconds can be used just to firm up certain cusps so they aren't distorted while you're placing the rest of the occlusal anatomy. then a final 20s cure can be done.

More on cracks

Observed at DrDs today and he reinforced the need to check teeth for cracks. He pointed out cracks on teeth and asked" what should we do about this?" The general answer was nothing (if there was no symptoms). But when there is a cracks in a symptomatic tooth then we are at a loss of what to do. He removed the restoration and placed a GIC temporary. He had the choice of placing a corticosteroid medicament over the base of the prep to sedate the pulp but that would just mask the symptoms and we wouldn't know if the disappearance of symptoms were due to replacing the restoration or due to the corticosteroid and we would not be sure of the state of the pulp. If the pulp was healthy on review, restoration or crown is the answer. If it is non vital, RCT then crown or exo is the answer. He also advised that if there were symptomstic cracks on an unrestored tooth. crowning asap is necessary.

A more complex treatment plan

Today I had the chance to treatment plan for an elderly gentleman in his 80s. He presented with a 20-30 year old maxillary full denture. It was stained, worn and had a missing 22 tooth. He saw a public clinic about this and they didn't replace the tooth but built up the opposing canine till it was in function with the denture. His lower teeth had a posterior edentulous segment, bilateral lingual tori and arrested caries on multiple teeth. his 45 exhibited some sort of pain on touch. All lower teeth were severely worn. Upper edentulous ridge was good volume and contour The patient was functioning fine with lower posterior teeth missing but upper denture was unsatisfactory. Plan aimed to replace upper denture crown lower canines and 1 first premolar, temporise painful tooth and build up lower incisors in composite. The lower teeth were to be lengthened by increasing the height of the restorations so occlusal/incisal prep was to be minimal if any. Interim appointment schedule: ...

More on cracks- Caries

Cracks allow bacteria to enter down the passageway and cause caries in the tooth. We often look for signs of caries radiographically and look for a lesion in enamel. Deep dentine caries can be present without enamel shadowing as the caries process starts through a crack which is rarely visible radiographically

Pins in teeth

Not always contraindicated as they say in the textbooks. Pins can provide very favourable retention for restorations where bonding is less predictable or the tooth is very compromised. Indicated when a cusp is lost (as there will be reduced mechanical retention from tooth structure) and the pin will be inserted in the location of the lost cusp. Location should be just inside the DEJ in dentine and care should be taken not to perforate the enamel wall or the pulp chamber. A good tip from Dr. L C is to place the drill tip in the sulcus and use that same angulation against the tooth structure to place your pin prep. Today when removing a GIC in the access cavity to replace with a composite core i encountered a pin in the remaining composite. The decision came whether or not to remove this pin and it was decided that removal was best. This was for 2 reasons: 1: the pin was solely in composite (the dentine may have been removed during endo access) 2: when completing the onlay prep, t...

Upper impression trays

Dr. L C said today that she never uses "upper trays" as the only time she needs to capture the palate is when she is doing full upper dentures (which she never does). Instead, use of a lower stock tray on the upper teeth can provide (amazingly) easier impressions for patients as the impression material isn't falling down the back of their throats. On another note, Lingual tori present a problem for seating trays and can be a source of bleeds and patient discomfort. Choosing an appropriately sized tray and pushing the tray far back enough to accommodate the tori is essential.

Cowhorn forceps

Cowhorn forceps are good for very broken down molars as they apply elevation forces to the furcation area and may even split the tooth favourably into separate roots which may facilitate easier removal. However, it is not always the best choice for non broken down molars as it may decievingly show more movement than has actually been achieved and has less surface area to grip the tooth with. For less broken down molars, a molar forcep may be the way to go

Failure of IDB

I gave an IDB with 2% lignocaine 1:80000 adrenaline today and the patient was feeling the extraction a bit so I gave an intraligamentary injection. Other than anaesthetising accessory nerve supplies (Buccal and lingual) it was suggested that the only way to achieve proper anaesthesia was to apply another IDB with mepivacaine

Cracks in teeth

Cracks are practically ubiquitous and with careful searching cracks can be found in almost any patient. Be wary of patients who present with unexplained sensitivity, heavily restored teeth, pain on biting and release of pressure. Cracks can still appear in unrestored teeth and fractures associated with these are generally much worse than in restored teeth and indicaate excessive forces are being generated e.g bruxism. Crowning is not always the way to go for any crack and although cracks are undiagnosed, they are also overtreated. The amount and extent of cracks should be matched up to the patients age e.g excessive cracks on young patients may require intervention. Also strategic teeth may consider early intervention e.g lonely molars with large restorations to "protect those teeth long term".  Treatment doesn't specify crowning teeth but involves cusp coverage which may be in the form of a porcelain overlay