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Showing posts from March, 2019

Hemostasis

Good hemostasis for restorative dentistry takes time. Subgingival restorative margins quite often have very inflamed gingiva assocaited due to the bacterial buildup that has caused the caries. especially if there is cavitated caries, there may also be gingival ingrowth into the cavity that can be difficult to manage. -If there is excess gingiva you must decide whether a gingivectomy or crown lengthening is required. This is dependant on the level of the crestal bone. A gingivectomy can be done with specially designed rotary burs without water (ceratip, gingiburs), high speed diamond burs, slow speed burs, scalpel, electrosurgery or Laser. Gingivectomy burs, Laser, electrosurgery also have the added benefit of causing coagulation which will assist with hemostasis after the gingivectomy. -Cord or teflon can be packed in the sulcus for retraction and hemostasis. Retraction cord can carry a hemostatic agent but the amount of retraction iasn't as great and it can allow gingival crev...

Pier (intermediate) bridge abutments

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In bridge design, a pier abutment is where there is a tooth in the middle of a bridge span. i.e a Fixed fixed bridge between the 17 and 13 with the with 14 included as an abutment (Figure 1). The issue with this design is that there are physiologic tooth movements in function and this design is generally used in long span bridges around the dental arch. Due to the shape of the arch, the physiologic movements are in different directions which will have unfavourable forces on the bond strength of the restoration. Anterior teeth will tend to be displaced labially and posterior teeth will tend to tilt mesially. In a fixed bridge situation, the abutment will always fail at the weakest interface which will lead to leakage and recurrent decay. This splinting effect may be beneficial in periodontally compromised teeth but with sound teeth it will often lead to a loss of restorative seal. Figure 1: An example of a pier abutment Alternatives to this design are dental implants, multiple ...

Temporising questionable teeth

Be very careful when managing the occlusion of questionably restorable teeth. The other day I had a strange appointment where I temporised an upper premolar with a deep carious lesion. the remaining cusps were thin but the tooth was an abutment to a partial denture. On checking the occlusion at the end of the appointment the patient bit down hard and there was a god almighty crack. The filling dislodged and the palatal cusp had fractured and was being held on by the palatal gingiva! Obviously there had been a very high spot in this case and all the force of the patient's (significant) bite had gone through the restoration and fractured the undermined cusp. One could argue that this would happen eventually through normal functioning but it did significantly reduce the longevity of the tooth. Before the fracture, she could consider a large cusp capped composite or a crown retrofitted to the partial denture. Both of these options can be considered very difficult or impossible now. W...

Tips from Full Mouth Rehabilitation course

I observed at Lincoln Harris' Full mouth rehabilitation course recently. I'll add small tips as they come to mind: A full mouth rehab is one of those things in dentistry that seems a lot more complicated than it is. In reality it can be broken down into smaller steps that if done well will lead to a successful and predictable outcome. Diagnosis is key to a rehabilitation. Discovering the cause of the breakdown as well as an accurate waxup is essential. After transferring a good waxup to the teeth, the resultant dentistry is just a bunch of crown and bridge work. Opening vertical dimension makes the patient more class 2. A class 3 patient will become less class 3 or class 1, and class 1 patient will become class 2 and a class 2 patient will worsen. When making a putty stent for transferring a waxup or for temporary crowns and bridges, take a putty stent of the waxed up model and reline it with light body impression material. Wax should stick well to a model. If it does...
Be careful with a partial denture on a patient who has had local anaesthetic. Firstly, due to a numb area, they may not be able to tell if the denture is seating fully. check how the major connector fits against the soft tissues and check the occlusion well to see if it matches the preoperative bite. Be sure to reinsert the denture for them after the procedure. It is very easy for them to catch their lip and cheek in one of the clasps without realising and cause soft tissue trauma. Be sure to mention in your post operative instructions to take care with inserting the denture till the numb feeling wears off.