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Dentistry/Cyst in a tooth


How long does it takes for a cyst to grow in a tooth and after tooth that had a root canal, for it to show up in a x-ray. Will it show up as a dark spot? Will jaw bone loss show up as dark spot too? Thanks a lot.

Dear Tim,

Cysts grow at different rates in different people and in different people under different circumstances, for a variety of causes.  Sometimes for no known cause.  If not already in place due to development, usually cysts take a long time to grow.  That's why they tend to be non-painful unless they compress a nerve or blood vessels.

Specific to a tooth:  Often what will happen is the nerve inside the tooth slowly becomes infected or dies (becomes necrotic).  The infection will spread slowly from the nerve through the end of the root into the bone surrounding the root.  This infection may be noticed by a dentist, usually on xray, or because it is beginning to cause pain.  The dentist will recommend a root canal to save the tooth and remove the infection.  Usually (90% of the time), the abscess will shrink over several weeks to several months of bone healing, and will disappear.  About 10% of the time, the abscess does not heal.  But because the infection has been eliminated from the tooth, the infection fluid inside the abscess will become a cyst.  This cyst may remain stable for years, or may continue to grow, destroying bone in its path.

It shows as a dark area, usually circular, around the root of the tooth.  The dark area is the bone loss showing on xray.  


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Howard Finnk, D.D.S., P.A., CEO


I am a Family, Implant and Cosmetic dentist. I will answer questions on any aspect of dentistry and matters relating to the smile, gums, jaws and lower face. Member American Dental Association, Florida Dental Association, Broward County Dental Association, and Atlantic Coast District Dental Association. I have served as District Council Member of Alpha Omega, as well as serving for one term as its President. I am also a member of The Vedder Honors Society, Broward Dental Research Clinic, and Mount Sinai Hospital Guild. I have served as a Volunteer for Project Dental Health and The Tri-County Dental Health Council.


Having attained over 30 years of clinical experience in private practice in Michigan, in 2001 I was re-certified by taking and passing the Florida State Dental Board Examination. After moving to Florida, I spent nearly 10 years re-honing my skills while working as an Associate Dentist for several large dental groups. In September, 2004, I was appointed Adjunct Clinical Professor at Nova University's College of Dental Medicine. I am certified in placement of Mini Dental Implants, and I am Director of The Florida Implant Center ( On March 1, 2010, at the age of 62, I began all over again by buying a dental practice near my home in the Fort Lauderdale area. As sole owner and Chief Dental Officer of the new Nob Hill Dental Center (, I can now carefully provide dental care to patients who care, all within a caring, joyful environment. Over my career lifetime, I have provided thousands of diagnoses, fillings, crowns, bridges, root canals, periodontal treatments, TMJ therapies, partials, dentures and extractions, and dozens of implants for my patients. The only aspect of dentistry with which I have very little experience is orthodontics.

American Dental Association, Florida Dental Association, Broward County Dental Association, Atlantic Coast District Dental Society, Vedder Honors Society, Broward Dental Research Clinic, Alpha Omega Alumni Association, and American Association of Dental Implantologists. Formerly, American Academy of General Dentistry, Michigan Dental Association, Macomb Dental Society, Detroit District Dental Society, Tri-County Dental Health Council (a charitable dental care organization)

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Bachelor of Arts and Sciences in Psychology from Wayne State University Doctor of Dental Surgery from University of Detroit College of Dentistry Adjunct Clinical Professor, Special Needs Department, Nova Southeastern University College of Dental Medicine, Fort Lauderdale, Florida

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