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  • BA Chemistry (2009), Iowa State University, Ames, Iowa
  • Doctor of Dental Surgery (2013), University of Iowa College of Dentistry, Iowa City, Iowa
  • Certificate in Endodontics (2015), University of Iowa College of Dentistry, Iowa City, Iowa
Special Professional Interests

Dr. Sullivan owes his interest in dentistry to his childhood dentist who proved that time in the dental chair did not have to be something to be feared. While in dental school, Dr. Sullivan developed a specific interest in endodontics, especially the nature of the procedures and the fulfillment that came in helping relieve people from pain. He elected to specialize and spent an additional two years at the University of Iowa in endodontic training. After completing the residency program, he joined The Dental Specialists.

Professional Activities
  • American Dental Association
  • Minnesota Dental Association
  • American Association of Endodontics

Verified Patient Reviews

4.8 out of 5 (240 Reviews) (77 Comments)

Overall patient ratings are based on the average score given by The Dental Specialists patients who voluntarily complete a satisfaction survey from Press Ganey, a nationally recognized firm dedicated to improving patient experience. Click to learn more about our patient ratings.

5 out of 5
January 26, 2021
Very happy to have seen/met Dr Sullivan. And a nice touch with the follow-up call.
5 out of 5
January 10, 2021
just outstanding care
5 out of 5
December 9, 2020
5 out of 5
November 11, 2020
I am very impressed with Dr. Sullivan, his dental assistant and your office staff and appreciated his time and expertise and the treatment plan he suggested that I am going to pursue with him and your staff.
3.2 out of 5
November 9, 2020
I wasn't given much in the way of after care instructions or what to look out for as far as infection etc.
5 out of 5
October 30, 2020
did a very good job, took time and explained what he was doing
5 out of 5
October 29, 2020
Superb care and knowledge. Highly recommend
5 out of 5
October 12, 2020
Dr. Sullivan and his nurse/assistant explained what they were going to do throughout the procedure. This was very helpful in helping me remain calm. Additionally, prior to the root canal Dr. Sullivan explained tooth pain and how the nerves react in one's mouth. I appreciated that he knew I would understand, and I liked learning something new about teeth.
5 out of 5
September 30, 2020
doctor Sullivan was amazing. great bedside manner explaining everything and ensuring all was smooth. appreciate the follow-up call from the actual dentist.
5 out of 5
September 15, 2020
This was the first time I had been to an endodontist in my life. Dr. Sullivan was very good in explaining my treatment options and was very good at answering my questions. I would rate my overall experience with Dr. Sullivan as excellent.
5 out of 5
August 25, 2020
first class !
5 out of 5
July 31, 2020
Dr Sullivan provided a clear explanation of expectations. Although the office was very busy he did not seem rushed at all.
5 out of 5
March 16, 2020
wonderful doctor, so pleasant and very professional
5 out of 5
February 27, 2020
dr Sullivan called me the next day!! not the office personnel, the doc! He was also very polite to and respectful of the hygienist and me. Dr Sullivan was very calm, explained every thing and made a root canal a "pleasant" experience!
5 out of 5
February 26, 2020
Exceptional treatment, had a root canal done on my back #1 molar. Dr. Sullivan found just the right spot for the anesthetic shots, which at other dentists have left me sore for days. This time when I went home and the anesthetic wore off I had no pain or soreness - didn't even need a Tylenol! Way to go Dr. Sullivan - informative, educational and all-around nice endodontist!!!
5 out of 5
January 25, 2020
Dr. Sullivan did an excellent job explaining the procedure and his thinking for what he was planning to do. He had the diagnostic image available to show me exactly what the problem was and how he would treat it. I had many questions, and he patiently answered every one. I appreciated the "crash course" in endodontics I received. I felt not only assured that I was in good hands, but I knew what was happening at every step of the way. I left better educated about the procedure and about basic jaw anatomy.
5 out of 5
January 16, 2020
Dr. Sullivan put me at ease by explaining what the procedure and process.
5 out of 5
December 28, 2019
Dr. Mark Sullivan was very good: professional, pleasant, calming, and informative and efficient. I recommend him back to my dentist to use Dr. Sullivan for referrals.
5 out of 5
December 27, 2019
Dr Sullivan and Hygienist were awesome, BEST dental experience I've had in years
5 out of 5
November 12, 2019
Dr Sullivan explained any concerns I had and the staff is great and friendly.
4.3 out of 5
November 6, 2019
I was not aware that 1) a filling will be required in addition to the root canal, 2) a temporary filling was used, and I will need to return to office for another visit to get a permanent filling.
5 out of 5
October 25, 2019
great chair-side manner by Dr and assistants.
5 out of 5
October 24, 2019
Dr. Sullivan was excellent. He had a very calm demeanor and explained things thoroughly to me. He took time and didn't rush into the procedure.
5 out of 5
October 7, 2019
so wish Dr Sullivan could be my dentist for everything :)
5 out of 5
October 7, 2019
Dr called following day to see how I was doing
5 out of 5
October 1, 2019
Dr. Sullivan followed up the next day (after a root canal was retreated). This doesn't happen with all doctors and dentists.
5 out of 5
October 1, 2019
Dr. Sullivan and his team were excellent. Really made me feel at ease while undergoing a re-treatment for a root canal.
5 out of 5
August 30, 2019
Very pleased with Dr. Sullivan, He made me feel very comfortable during the procedure. I had no pain or issues afterwards. Also the phone call I received from Dr. Sullivan the next day to check how things were going after procedure. I would highly recommend anyone to come to your office. Thank you Dr. Sullivan
5 out of 5
August 19, 2019
I was most appreciative of the time the specialist spent with me explaining all facets of what the issue was and how it was to be addressed.
5 out of 5
August 2, 2019
Very good explanation of the problem and potential solutions
5 out of 5
July 19, 2019
Dr. Mark Sullivan is a very caring Doctor. I am forever grateful to him for putting a smile back on my face.
4.8 out of 5
July 3, 2019
good initial visit
4.9 out of 5
May 9, 2019
due to Dr. Sullivan's examination and observation, the root canal was done on the adjacent tooth rather than the one originally planned.
5 out of 5
May 1, 2019
I have a lot of confidence in Dr. Sullivan and he is very respectful. Inspires confidence.
5 out of 5
April 27, 2019
Treatment went well.
5 out of 5
April 17, 2019
I was very happy and impressed with Dr Sullivan's "bedside manner" in talking through the options and treatment. He explained everything in layman's terms with drawings and competently took my questions with patience
5 out of 5
March 7, 2019
Dr Sullivan was very professional and even made a phone call to see how I was doing.
4.9 out of 5
March 6, 2019
Dr. Sullivan was excellent! I appreciated his calmness as I was very nervous getting a root canal! He showed great care for my well being and gave me a heads up throughout the procedure so i would know what to expect. He gave me a follow up call the next morning to see how I was doing - what a great courtesy!!!
5 out of 5
February 28, 2019
Dr. Sullivan was very pleasant to meet with and quickly established to me his credibility.
4 out of 5
February 27, 2019
Excellent treatment during root canal- no resting hands on my mouth/lips, hitting teeth with tools, etc. I appreciated the vocal "next steps" as he was performing work, and even reccomended his skill after I returned to my office. HOWEVER, within hours I developed a complication (Endodontic Flare-up) and he was resistant to acknowledge something might be wrong (IT WAS) and that perhaps a more serious painkiller or exam was necessary. It took 2 emergency after-hours phonecalls and a another call with the clinic the next morning to get another doctor to see me. It's troubling to be dismissed for a legitimate medical issue- especially when I have such personal experience- and where PAIN was being blatantly ignored and downplayed as "discomfort."
5 out of 5
February 26, 2019
I had great confidence in Dr. Sullivan! He explained everything very well and eased my worry.
5 out of 5
February 8, 2019
Received a follow up call from the doctor. Very professional!!!
5 out of 5
January 30, 2019
I appreciated Dr. Sullivan calling me the morning after my appt.
5 out of 5
January 27, 2019
Absolutely outstanding doctor!!!
5 out of 5
January 17, 2019
Dr. Sullivan was great. I would highly recommend him. No pain during my root canal.
4.9 out of 5
January 4, 2019
Would have been nice to have something in writing to take with me on "eat soft foods, rinse twice daily..."
5 out of 5
December 29, 2018
Dr. SULLIVAN was great
5 out of 5
December 18, 2018
I expressed having some anxiety about procedures such as this and was treated extremely well by both professionals in the room. I left feeling calm, cared for, and with very little soreness. Thank you..
5 out of 5
November 10, 2018
All in all I was very pleased with this doctor, office and staff.
5 out of 5
October 27, 2018
Through, gentle, kind and a great dentist!
5 out of 5
October 18, 2018
Dr Sullivan Is very good and makes you feel very comfortable. He called to check on me the next day and Iwas very impressed with that care and concerned
5 out of 5
September 26, 2018
I was very surprised and impressed that Dr. Sullivan called personally to see how I was doing.
5 out of 5
September 21, 2018
I can't say enough about how impressed I was by Dr. Sullivan and the Dental Assistant. I was in a lot of pain, and they were both compassionate and explained everything very well.
5 out of 5
August 24, 2018
5 out of 5
June 30, 2018
Dr. Mark Sullivan was very pleasant, caring, & comfortable to be with. This helped me to relax for a long & "challenging" procedure.
5 out of 5
June 13, 2018
Dr. Sulivan is amazing! No pain and did a great job. Even called the next day to check up to see how I was doing. You dont see this kind of care anywhere else!
4.9 out of 5
May 29, 2018
I could have maybe used a few more updates throughout the root canal to know if we were halfway done, etc. He let me know when we were almost done but I would have preferred to know a little earlier as to where we were at with things. It's a long time to keep your mouth open that long! :)
5 out of 5
May 4, 2018
Dr. Sullivan was wonderful. I greatly appreciated his follow up calls to make sure I was ok. He is clearly competent and skilled, but also very caring and personable.
5 out of 5
April 13, 2018
very impressed that Dr Sullivan called me the next day himself to tmake sure I was recouping just fine. I'm accustomed to just having a receptionist follow up.
5 out of 5
March 29, 2018
Dr, Sullivan and his team did a great job understanding my anxiety for the treatment, listened to my concerns and acted on my concerns. I appreciate the respect that I received during my treatment.
5 out of 5
January 17, 2018
Dr. Sullivan was very easy to work with. He clearly explained what was going to happen and was happy to answer any questions I had. He seemed extremely competent and engaged in the process. I felt confident he was going to do a good job.
0.3 out of 5
November 25, 2017
I arrived in pain and left untreated. Even after being referred to another specialist, I waited over 48 hours for a follow up scheduling.
5 out of 5
November 13, 2017
Dr. Sullivan was beyond fantastic!!!!!!!!!!!!!!!!!!
5 out of 5
November 1, 2017
My doctor (Dr. Mark Sullivan) and assistant (dang, forgot her name ) were amazing. They clearly had read my intake forms and were able to talk about a few of my concerns. This was my first appointment and I was referred in by my dentist. I was apprehensive about the procedure and the cost. They did a great job explaining the procedure. They took the time to listen to my concerns and make me feel important. I didn't get the feeling they were trying to rush me in and out or that the doc was seeing another client at the same time. It was expensive but Dr. Sullivan was worth every penny. Feel Free to use me as a reference!
5 out of 5
October 30, 2017
was very nice that the doctor called the next day to see how everything went
5 out of 5
October 17, 2017
Dr. Sullivan truly cared about my well being and made sure I was comfortable during the entire process.
5 out of 5
September 13, 2017
Dr. Mark Sullivan called me the next day to make sure I wasn't still having pain. I thought that was very nice.
5 out of 5
September 1, 2017
the doctor did a great job setting my nerves at ease.
5 out of 5
August 8, 2017
Though not a big deal, it would have been helpful if the dentist had given me periodic explanations of what he was doing as he was working through my root canal.
5 out of 5
July 5, 2017
Dr Sullivan was perfect.
4.9 out of 5
June 17, 2017
I appreciated being treated as an adult, the time spent with me and the degree of explanation of alternatives and answers to my questions and concerns.
5 out of 5
May 15, 2017
This was my first root canal treatment. The doctor explained the procedure and potential outcomes thoroughly and put me at ease.
5 out of 5
March 27, 2017
Dr. Sullivan was very thorough, supportive, caring, patient, helpful.
5 out of 5
February 27, 2017
Dr. Mark Sullivan was great. Especially his follow up surprised my positively.
5 out of 5
February 17, 2017
My doctor did a great job of explaining to me the procedure in terms I could easily understand. Made me feel comfortable during the whole procedure and I could tell he was working in my best interest.
3.9 out of 5
February 4, 2017
The dr examined me for about 5 minutes before telling me I don't need a root canal
2.1 out of 5
January 16, 2017
Doctor was unwilling to discuss, explore and try a less expensive and less invasive treatment that had no downside and very low risk and was arrogant in stating his option was the only option available and would not even consider the other.
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