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Colorado’s LEADING
Dental Temp Agency

After being employed in a dental office from 1974–1983 and experiencing the inconsistencies and problems in the workplace, Barb Sumner, Founder and CEO of Assistance On Call, Inc. (AOC), envisioned a better way.  Barb set out to change Colorado’s dental staffing industry on both sides of the equation, from the doctor’s point of view AND through the eyes of the employee.  Assistance on Call, Inc. (AOC) was established in 1983 and has remained Colorado’s premier dental staffing company.


AOC’s inception took place in a 700 square foot home in south Denver.  A picnic table represented the office “desk” and a rotary dial phone was Barb’s main method of communication. The only other technology AOC used, at that time, consisted of a reel-to-reel answering machine, a manual typewriter, and a radio shack entry level computer with a cassette tape backup. The infancy stage of building a business is never easy, and those lean times lasted 10 years.

With persistence and dedication throughout the years, AOC has become the definitive leader in the dental staffing industry.  Assistance On Call, Inc. now boasts a one-of-a-kind proprietary scheduling software system (designed by Barb), a complete system of networked computers, a state-of-the-art phone system as well as an integrated website.

AOC, temporary and temp-to-perm dental staffing company, is currently located in a beautiful, highly efficient office in Lakewood, Colorado. With 40 years of experience, 24 hour service, and continuous monitoring of the needs of the dental community, we look forward to assisting you with all of your dental staffing needs.

AOC is steeped in Barb’s high ethical standards and constant emphasis on exceptional morals and values.  As far as Barb is concerned, this is the only way to conduct business – with integrity and respectability.  AOC refuses to compromise on the quality of the service it provides.  Thank you for trusting Assistance On Call, Inc. (AOC), the leading temporary and temp-to-perm staffing company in Colorado …. since 1983.

About Assistance on Call

860 Tabor St. Suite 203
Lakewood, CO. 80401
Please contact us:

<     Our Lakewood, Colorado office 


“For over 40 years I have been using AOC’s hygienists as my “own” full-time staff. In this time, I have never had to cancel a patient due to a sick hygienist! AOC also freed me up to focus on my practice by taking care of all the ’employer’ related issues…”
– S. Jackson D.D.S.


Your Placement Specialists


Shannon Ferguson, Manager/CEO

I am one of the few Colorado natives. I grew up in Golden and currently live with my two amazing daughters and my wonderful husband in Arvada. When not working, I am driving my girls to and from sports and enjoy watching them compete and do what they love. Also, I help coach a competitive softball team, which brings me great joy. Our family loves hiking, binge watching various Netflix shows, and doing just about anything as long as we are together. 


Prior to my journey with AOC, I was a teacher. I taught several grades, and eventually got my Masters degree in Culturally and Linguistically Diverse Education, which opened the door to working with multilingual learners and their families. Teaching filled my heart and developed my problem solving and critical thinking skills for 15 years. I worked with the most incredible people, and am beyond grateful for how this profession impacted my heart and mind.  I worked part time for AOC for over two years when I decided to jump on board full time. Working for AOC fulfills my desires and passion for helping people, problem solving, critical thinking and working collaboratively through a common vision. 

I am proud to be a part of a team that values personal attention, integrity and quality. Both the employees and clients who serve and utilize AOC are some of the most exceptional people, and I am thrilled to continue to learn and grow with the most superior staffing company in the industry. 

Diane, Bookkeeping and Staffing Coordinator

I was born in Michigan, raised in Illinois, and have lived in Colorado much of my life. After studying Finance and English at Arizona State University, I returned to Colorado and worked in various Executive Assistant positions, ranging from accounting firms to law offices.

After raising two amazing children, I find myself extremely blessed to be a part of the AOC team. I am the first point of contact in the AOC office and provide administrative support to the entire organization. I am also involved as a  Staffing Coordinator. It is rare to find such a well-run and capable company that consistently upholds a high level of professionalism and excellence. I have never worked with a company that serves its clients and employees with such respect and integrity.

When not working, I can be found spending time with my family, on a ski slope, in a gun range, or enjoying peace and quiet with a good book and my two sweet Ragdolls.Diane, Bookkeeping and Staffing Coordinator

Bob, Staffing Coordinator


I am a Colorado native, raised in North Denver.  After receiving a college degree, I moved to California.  I have lived in many parts of the country since that time and worked in various fields, all of which have allowed me to interact with people in a customer service capacity.  I returned to Denver in 2001.


After an eight year hiatus from AOC,  I decided to re-join the AOC team in February 2019 and am very excited to be back.  There have been many new updates at AOC since I was last here; however, the high-quality standards that Barb has always had regarding the care of her employees and customers have not wavered.  The efficiency of Barb’s customized program has been very rewarding to learn and utilize.  AOC continues to operate with the same incredible integrity that has always set them apart from other staffing companies.  It makes me very proud to be part of the AOC team once again! 


I am blessed with a wonderful daughter who is a nurse in Littleton.  My time away from the office includes spending time on home projects, supporting our Colorado Rockies, karaoke and enjoying live local music with friends.

                         Bonnie, Executive                                Assistant/Placement coordinator

I was born and raised in Spokane, Washington. I have 3 grown children and a grandson. My daughter, is a CT tech at National Jewish Health. My youngest son, is a welder. My oldest son, served in the Army, is now an Engineer.

I was a dental assistant for the past 35 years. I have always had a passion for dentistry. Sadly, for medical reasons, I needed to find another career. I have had a relationship with AOC since relocating to Colorado in 2008.

I met with Shannon at AOC in 2022 , told her about my plan.  After talking awhile, she thought that I would be a good fit at AOC!  Shannon presented me with a job offer!  I am now Executive Assistant/Placement Coordinator at AOC It is very exciting to see how this amazing company works and why it is so successful for almost 40 years.

When not working I enjoy taking care of my grandson. I love travel, furniture refinishing, I also make jewelry.

Barb, Owner


I have enjoyed a lengthy and rewarding career in the dental profession, having begun my path in the dental field in 1973 prior to launching my company, Assistance On Call, Inc.  (AOC) in 1983. I am committed to perfecting the staffing needs of the dental community. I feel strongly that we are a relationship-based company, we treat our clients and employees with the respect they deserve.

I am an honest and loyal individual. I lack patience and have a ‘no tolerance’ policy when it comes to disloyalty, incompetence, and dishonesty. My standards are extremely high when it comes to my company and my personal life. I was born and raised in North Denver in a very traditional Italian household, which may – in part – explain my strong values.

When not working, you can find me on the golf course with my husband of over 40 years, or on long walks with our two rescue dogs. I am a very strong supporter of animal rights. I enjoy spending time watching my grandkids, participate in sports. Cooking, reading, golf, movies and spending time outdoors in beautiful Colorado.  I also enjoy watching most professional sports teams from my recliner!


Assistance On Call, Inc.  (AOC)  is an innovative dental staffing company, providing exceptional Dental Professionals for our Colorado dental offices. We are committed to providing outstanding customer service through integrity, loyalty and mutual respect. We view ourselves as partners with our doctors and employees.  We refuse to compromise on the quality of service we provide.  Our goal is to always be the premier temporary and temp-to-perm dental staffing company in Colorado ...since 1983.

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