QC Dental | Chatswood Dentist

Technical details

Learn about the technical details on how dentistry is performed!


Technical details

+ Fillings

  • A filling is determined is required either by visual inspection or x-rays.
  • Depending on how deep the filling is and how sensitive the tooth is, the tooth will be numbed.
  • All the decay is then removed by drilling.
  • If required, a thin band is placed in between the teeth, so the fillings have a natural shape and do not stick to the adjacent teeth.
  • The tooth is then selectively acid etched and bond placed. This is the most important part to ensure the filling does not fall out.
  • The bond we like to use is Scotchbond Universal, from 3M.
  • A low viscosity resin is injected and light cured in the cavity to ensure 100% adaption to the tooth.
  • Because the curing of the resin produces shrinkage, it is placed and cured in small sections, to mitigate this. The small sections also ensures the light can penetrate the resin fully.
  • Once the tooth is built up enough, the matrix is removed and the filling is adjusted to fit the bite.
  • The matrix we like to use is the V3 sectional matrix system, from Dentsply. It provides an extremely natural contour and tight contact so food doesn't get stuck in between your teeth.
  • The final process is to polish the surface so it is comfortable to your tongue and looks good.

+ Root canal therapy (RCT)

  • RCT is determined to be needed by x-rays, symptoms, visual inspection and nerve testing.
  • The tooth is anaesthetised.
  • Any decay is removed and a tunnel is made in the tooth to access the nerve of the tooth.
  • The canals that the nerve runs down inside the roots of the tooth are found. Depending on the tooth, it will have from 1-4 canals. There are some rare cases with more than 4.
  • The nerve is removed by small and thin stainless steel files and disinfecting solution.
  • The most important principle of RCT is to disinfect the tooth. This is achieved by the disinfecting solution being able to reach the entire root system, especially the tip of the root.
  • The length of the roots is determined by a machine called an apex locator.
  • The canal must be enlarged to a size that allows the disinfectant to flow and become in contact with the root system. This is done by using sequentially larger files to shape the canal.
  • Modern rotary files have increased the efficiency, safety and effectiveness of RCT. We use either Protaper Next and Twisted Files Adaptive, depending on the case.
  • Once the canals are shaped well, the solutions are vibrated to ensure maximal disinfection and remove debris and air bubbles.
  • We do not want to leave the tooth empty inside so it is filled with a special material called gutta percha. It is a natural material from the sap of a palaquium gutta tree.
  • The method of filling the root canals that we use is by heating the gutta percha, to soften it, to increase the adaptation to the canal. It is a method specialist endodontists like to use but not many general dentists use.
  • Once the canals are filled, the rest of the tooth is filled with the usual filling material.
  • 2-3 appointments are usually required to do all the above, to ensure maximal disinfection.
  • Oftentimes, a crown should be placed on the tooth, to protect it from breaking.

+ Crowns and porcelain fillings

  • Crowns and porcelain fillings are the best way to restore teeth that have large cavities/fillings or cracks.
  • The tooth is anesthetised if required.
  • An impression of the tooth is made, to be a template for the temporary restoration.
  • The tooth is shaped as required.
  • Sometimes, flowable composite resin is placed on the tooth to prevent sensitivity and provide a good shape to fit the porcelain.
  • An impression of the shaped tooth is made with highly accurate material.
  • The shade of the restoration will be chosen and photos may be taken so the ceramist can make it look extremely natural.
  • A temporary restoration is made and stuck to the tooth using temporary cement. It is designed to be removed with relative ease at the next appointment.
  • After 1-2 weeks, you return to the dentist for the permanent restoration.
  • The tooth will be anesthetised if required and the temporary is removed.
  • The permanent restoration is then checked to ensure it fits perfectly and looks great.
  • Depending on the type of porcelain, it may be etched with a dangerous hydrofluoric acid. Fortunately, this is done outside of your mouth.
  • Then it is silanated, so it can stick to the resin cement.
  • The tooth is also selectively acid etched and bond placed.
  • The resin cement is injected either on the tooth or fitting surface of the porcelain.
  • We use Relyx Ultimate resin cement, from 3M. It has been found to be very strong and it looks very good.
  • The porcelain restoration is then fitted onto the tooth and excess cement is removed.
  • The cement will set by itself but can also be accelerated by shining a strong light onto it.
  • The bite is then checked and sometimes requires minimal adjustment.
  • We will take a photo so we can show off our work!

+ Wisdom tooth removal

  • The tooth is determined to be removed by both visual inspection and a full mouth x-ray (OPG)
  • The tooth is anaesthetised and checked to ensure it is fully numb.
  • Depending on the situation, a cut in the gum will be made, to expose the tooth and surrounding bone.
  • Again, depending on the situation, some bone may need to removed and tooth sectioned into separate pieces.
  • Once the tooth physically has enough space to come out, it will be lifted out of the tooth socket.
  • A stitch may be required to close the wound, especially if the gum was cut.
  • You will be given some gauze to bite on for 30 minutes, to apply pressure and stop bleeding.