dental oncologyReferral Dentist for Dental Oncology / Cancer Dentistry

Dr. Penchas is a Houston, Texas based Maxillofacial Prosthodontist with a certificate in Dental Oncology from M.D. Anderson Cancer Center. He is one of a few select dentists in the United States trained to treat and prevent complications from radiation and chemotherapy to the mouth and head and neck.

As a dental oncology specialist, he is happy to provide your patients with the support they need before, during and after radiation and chemotherapy treatment.

Dr. Penchas is a cosmetic dentist, but also a dental oncology expert. This means he is trained to help a patient undergoing cancer treatment in the head and neck area. If your patient is  receiving radiation or chemotherapy to the head and neck, they may need his help.

Chemotherapy and radiation to head and neck both have short and long term effects and Dr. Penchas will help you deal with these effects.

The purpose of radiotherapy is to reduce the growth of tumor cells.  Unfortunately, tissues in the mouth are affected by radiotherapy and special care should be taken to help prevent infections in the mouth.

Ways of preventing these problems start with an examination by a dentist.  If any dental procedures are necessary before radiotherapy, they usually can be done while the bone can heal properly.



Dry Mouth is very common after the first week of radiotherapy and may persist as a permanent effect.  This depends on how large the area to be radiated will be.  This will vary from patient to patient.

Mouth Ulcers are a common occurrence during radiotherapy.  Sometimes, these ulcers are preventable by simple oral hygiene care and a cautious diet.  These may occur on the lips, tongue, roof of mouth and inside the check.

Swollen gums are another side effect that may occur if tartar has accumulated around and below the gum line of your teeth.

Dental Abscesses can occur if broken or impacted teeth are present during radiotherapy.




While the redness/ soreness will go away soon after your radiation is complete, the changes in taste and dry mouth are permanent.  There are some ways to reduce the discomfort caused by these side effects.


Radiation caries is defined as tooth decay (cavities) that results from dry mouth following radiation therapy. Saliva (spit) protects teeth in 2 ways.  First it helps to rinse food off of your teeth and secondly it helps to neutralize the acids that cause tooth decay.  So when there is a decreased production of saliva, it protects the teeth.


The best way to prevent tooth decay is to keep your mouth meticulously clean. It is helpful to develop a routine; Dr. Penchas recommends four easy steps.

  1. Brush your teeth with a super-soft toothbrush
  2. Floss teeth by sliding the floss up and down each side of each tooth, making sure that the floss hugs the tooth
  3. Apply your prescribed fluoride using your fluoride carrier (described below) to help strengthen your teeth.
  4. Baking soda rinses (1 tsp. baking soda to one quart of water) to neutralize acids that cause tooth decay


Fluoride carriers are custom molded plastic trays made by Dr. Penchas to be filled with prescription fluoride gel to help prevent decay and strengthening your teeth.

How Do I use my Custom Fluoride Carriers (Trays)?

  • At bedtime, remove your dentures from the mouth.
  • Brush and floss your teeth as you would normally with soft toothbrush and regular toothpaste.  Note: It is very important to remove all food and plaque from between teeth before using fluoride. Food and plaque can prevent the fluoride from reaching the surface of the tooth.
  • Place a thin ribbon of the fluoride into each fluoride tray so that each tooth space has some fluoride, filled about 1/3 of the way.
  • Place the trays on the upper and lower teeth and let them remain in place for 45 minutes. Only a small amount of fluoride should come out of the base of the trays when they are placed.

After 45 minutes, remove the trays and thoroughly spit out the excess. Very Important – do not rinse mouth, drink or eat for at least 30 minutes after fluoride use.

When is the best time to use my fluoride carriers?

The best time to use your fluoride carriers is right before bed.  It should be the last thing you do before you go to sleep.

How do I take care of my fluoride carriers?

Rinse your trays thoroughly after each use and allow them to air-dry overnight, outside of their container. Do not boil the trays or leave them in a hot car because they may warp or melt


After head and neck radiation, your ability to heal after a tooth is removed is decreased.  If a tooth is removed in an area that has had radiation, it is a significant chance (30%) that a non-healing bone infection will develop called osteoradionecrosis.  If this infection develops, further surgery may be needed to remove infection.


It is really important that your dentures are comfortable.  If your dentures cause sores areas, it is important  you take out your dentures until you can see your dentist.  Your dentist has special techniques to find the area on your denture that is causing the problem and make you dentures more comfortable to wear.


You should brush your teeth at least twice a day: in the morning, after breakfast and before bedtime, after dinner. Super soft toothbrushes should be used to help reduce irritation. Brushing should be done in a gentle, circular motion as close to the gums as possible. A soft toothbrush held like a pen can be used carefully during radiotherapy.  If your mouth is too tender or sore to use a toothbrush, a folded square gauze pad can be moistened with water and gently wiped over the surfaces of the teeth and/ or gums instead.

Hint: If a particular toothpaste burns or irritates the mouth, try a toothpaste that is specially made for children or people with dry mouth.

Flossing is recommended as well as the use of a water-irrigating device, on a low setting, to eliminate food between teeth.

Baking soda rinses (1 tsp. baking soda to one quart of water) may be used throughout the day to sooth the sore and dry mouth.

Eat small bites and chew thoroughly when using these numbing medicines to reduce the risk of choking.

Keep mouth and lips well lubricated with a water-based lubricant. Petroleum jelly (Vaseline) repels water and is not recommended for use.

When the inside of your mouth is sore, take out your dentures and leave them out until the mouth heals.

Things to avoid during radiation treatment

  • Avoid foods that have a rough consistency such as:  tortilla chips, fried foods, nuts, etc.
  • Avoid wearing complete dentures during radiotherapy, as this will promote nausea and vomiting.  Wearing dentures will also promote development of mouth ulcers
  • Avoid a prolonged dry mouth which may tend to develop during sleep.  Keep plenty of water at bedside.
  • Avoid carbonated beverages and juices that are acidic like grapefruit or orange juice.
  • Avoid high alcohol containing mouthwashes like Listerine or Scope.  Use only the salt and soda solution.
  • If vomiting occurs, rinse with soda and salt solution; this will neutralize the stomach acid.  Prolonged contact of stomach acid in the mouth will cause mouth ulcers.