The Alphabet Blog: D is for Dentin

The Alphabet Blog: D is for Dentin

Dentin is the layer of tooth beneath the outer enamel layer and is important for a few reasons:

The color of dentin shows through the enamel and imparts color to the tooth.

In this photo, the dentin is the darker inner layer:

The next two pictures are great examples of what acid in plaque does as it works its way through the outer enamel into the dentin.  It turns the enamel frosty white, as acid does to glass, and turns the inner dentin dark brown. 

Dentin is flexible and helps prevent fracture of the brittle overlying enamel.

Dentin contains tubules that transmit painful stimuli like cold and sweet.  Are your teeth sensitive?  Blame it on the dentin.

Dentin allows faster spread of bacteria from the outside of the tooth to the inner nerve (pulp).

That’s dentin in a nutshell.

Love your smile,

Dr. Cook

The Alphabet Blog: C is for Composite

The Alphabet Blog: C is for Composite

Composite is tooth-colored filling material.  Composite filling material, a combination of plastic and glass spheres, has been used for over 60 years.  Dentists in the U.S. place more than 122 million dental composites each year.  Many dentists today have stopped placing amalgam (aka silver or mercury) fillings for various reasons.

At Cook Family Dentistry, I no longer place amalgam restorations because in order to do so, I have to remove much more tooth structure and the tooth is left at a higher risk of breakage.

Benefits of composite filling material:

  • They are bonded to the tooth structure:
    • this blocks out bacteria, acids, sugar, saliva from leaking between the filling
      material and the tooth
    • bonding also helps support the remaining walls of the tooth
  • A composite filling can be more narrow and shallow with amalgam/silver fillings because composite is a more flexible material and is bonded into place instead of being held in by mechanical retention only, which undercuts the remaining walls of the tooth.
  • Composite can be repaired because it will bond to itself.  Amalgam does not bond to itself.
  • Composite is tooth-colored, so dark decay that may start to grow in the tooth later can be differentiated from the filling.  Amalgam/silver fillings camouflage new decay in x-rays and also upon visual examination.
  • Esthetics.  Composite fillings are matched to the shade of the natural tooth.

Here are step-by-step photos of the process of removing an old leaking amalgam filling and replacing it with composite:


Before: Old amalgam filling, leaking around the edges. Decay starting in pits and fissures.

Looking under the old filling. The tooth is partially cleaned out here.

Bevel Example

A cleaning solvent removes surface debris, bacteria, and saliva while creating a rough surface to increase the bond strength of the new filling to the tooth surface.

Bonding agent is brushed into the clean surface.

Bevel Example

Tooth-colored composite filling material that matches the tooth shade is injected into the tooth.

The soft composite filling material is packed into place and sculpted before it is hardened with a blue curing light.

Bevel Example

A thin coat of flowable filling material is applied to the filling to better seal the margins of the filling/tooth.

After the filling is hardened, we mark the bite to identify high spots.

Bevel Example

Polishing the filling and removing high spots.

The finished product. Healthy tooth structure, conservatively cleaned and well-sealed. The tooth surface is now smooth and cleansible to a toothbrush. (no narrow grooves for bacteria to hide in).

In this example of a filling we placed in my office, you can see how a silver filling shows through the tooth and makes it look black/grey.






Dr. Cook

The Alphabet Blog: B is for Botox

Botulinum toxin is used to treat patients with certain neuromuscular conditions. In the 1950s, scientists discovered that botulinum toxin can reduce muscle spasms that cause chronic muscle cramping, pain, and wrinkling of skin.  The solution prevents some of the muscle fibers from contracting. One of the most researched medicines in the world, BOTOX® treatment is approved for medical uses across the world. BOTOX is one of three brands of botulinum toxin.  The other two are Dysport and Xeomin.  Dentists have started offering botulinum therapy for patients who clench their jaws so much that even the use of a protective mouth guard does not prevent them from breaking teeth and causing headaches and migraines.  Some dentists also offer the treatment for wrinkles.

 BOTOX® is the first medicine to be studied and then approved by the FDA specifically for the prevention of headaches in adults with Chronic Migraine who have 15 or more days each month with headache lasting 4 or more hours each day in people 18 years or older.

At Cook Family Dentistry, we recommend a removable oral appliance (“night guard”)  as the first line treatment approach for patients who exhibit signs and symptoms of chronic clenching and grinding.  Although it is commonly referred to as a “night guard,” patients benefit from wearing the appliance any time that they clench and grind. Many patients report clenching and grinding at work or while driving and notice a correlation between clenching/grinding and stressful times.  If the patient wears the guard but continues to experience fractured teeth, fillings, and crowns, headaches, or migraines we discuss botulinum therapy.

In addition to tooth problems, some patients report problems with their jaw joint (the Temporomandibular Joint, or TMJ) such as pain, limited opening, and lock jaw. For these patients, we first recommend gentle, conservative home remedies such as soft foods, warm compresses, stretching exercises anti-inflammatories (ibuprofen).  If home remedies fail to give relief, we often recommend a night guard and may refer them to an Oral Medicine specialist.

We have administered bilateral injections of the botulinum toxin neuromodulator Xeomin.  Xeomin is a brand name that is administered in the same dose as the Botox brand with the same efficacy and duration.  Xeomin has been studied and used extensively and has been proven to be exceedingly effective and safe.  For patients who clench their teeth, the benefits of Xeomin include reduction of:

  • tooth fracture
  • tooth loss
  • toothache
  • jaw ache
  • muscle soreness

  • headaches

  • migraines

Injection of Xeomin for clenching involves easy, gentle injections into the masseter muscles and in some cases, additional injection into the temporalis muscles.  Masseter injections are administered from the outer surface of the face near the lower border of the jaw bone.  Temporalis injections are administered into the bulk of the muscle above the temple area around the hairline.   Although neuromodulators for esthetic (upper face) areas often take days to take effect, my patients who have received the injections for clenching report relief within 24 hours, and sometimes immediately.  The effect typically lasts 4 months.  My patients have reported lasting effects of from 2 to 4 months.  Every patient in my office who has received botulinum therapy has raved about the relief that they finally achieved from chronic pain.

The National Institutes of Health recognizes this safe and effective treatment.  See  and  for more information.

The following is a link to two studies demonstrating the safe and effective use of neuromodulators for clenching.

The Mayo clinic statement on the use of neuromodulators to reduce muscle overactivity:

In addition, see this link from Pub Med, titled Interventional neurology: botulinum toxin as a potent symptomatic treatment in neurology.

To reduce the chronic, severe clenching forces that have caused you tooth pain, tooth fracture, filling and crown fracture, tooth loss, and headaches, I recommend masseter injections of Xeomin neuromodulator every four months.  It is hoped that in reducing muscle activity, the muscle will retrain itself, through atrophy and decrease the need for treatment over time.  This is not guaranteed, but has been reported.

I hope this information has made your life a little better.


Dr. Amy Cook


Implant crown delivery

We recently delivered two crowns that are supported by dental implants.  Here are a few pictures of the process:

After the surgeon placed the implants, he attached a healing cap to each one.  The round, silver healing caps cover the implant for a few months after they are placed to allow bone to grow around the implants until they are well-anchored.  The implants, just like fence posts in cement, must be firmly anchored before attaching the crown and applying forces.

Here are the implant crowns in place while we check the fit.  The hole in the center is for the screw that holds the crown securely to the implant.

Once the fit is confirmed, the screws are torqued to 35 Newton/cm, covered, and the access hole restored to a natural look.  The patient can chew with these teeth immediately without restrictions.


Dr. Cook

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