The Truth About Mini-Implants

What is the difference in an Implant and a Mini-Implant?

The first modern, root form implant was developed by a Swiss orthopedic surgeon in the 1960’s. The mini-implant was developed in the late 1970’s but not put into use until the 1990’s.

The original intended use of mini-implants was for temporary use to help hold temporary teeth while more stable, conventional implants healed. That is part of how mini-implants received FDA approval.

Mini-implants received long term approval through a loophole that many medical devices use to get on the market for patient use. The regulatory review process known as 510(k) for a section of the FDA law covering medical devices. Manufacturers typically show their product has “substantial equivalence” to a “predicate device” that has already been legally marketed. A claim of substantial equivalence does not mean the device(s) must be identical. Substantial equivalence is established with respect to: intended use, design, energy used or delivered, materials, performance, safety, effectiveness, labeling, biocompatibility, standards, and other applicable characteristics.
That standard can perpetuate problems. Your device is similar but only in theory. It can fall within certain narrow standards to get approval and then be used in off-label means once it is on the market.
A conventional implant is considered to have an overall diameter of 3.0mm or greater and a mini-implant is one with a diameter less than 3.0mm. A regular implant is typically two pieces: the part that goes into the bone that replicates the missing tooth root and a piece that ties to it called the abutment. This connection is vital for several reasons. First, teeth and bone are rarely in a straight line. In the front of your mouth, teeth have more of a shovel shape with a bend as they leave the bone and emerge through the gum tissue. Second, the shapes of teeth are much wider than the diameter of a mini-implant (less than 3mm). This abutment allows the doctor to replicate the shape a natural tooth has as it emerges through your gums into the oral cavity. This is much better cosmetically because the gum tissues contour to the abutment giving you the most realistic and esthetic profiles possible that most replicate what you naturally had. It also gives contours as nature intended allowing for normal homecare and maintenance making cleaning identical to natural teeth. The abutment connection also allows the doctor the ability to correct for angles that your body dictate to get your bite (occlusion) correct for less stresses and more longevity.

The mini-implant procedure was originally intended for medically compromised patients, patients with extreme bone loss that cannot be rebuilt and financially compromised patients. That use has been expanded, inappropriately, to all patients and all applications.

False Claims about Mini-implants:

They hurt less than conventional implants…in both mini and conventional implants, the bone and gums are numbed, a small opening is made for the drill and then a small hole or osteotomy site is drilled to the diameter of the implant being placed. You would be hard pressed to tell if a 2.2mm osteotomy site or a 3.3mm or 4.7mm osteotomy site was prepared. I have patients who have conventional implants placed tell me almost daily that they took nothing more than ibuprofen and had no pain. I think the amount of pain has more to do with the surgeon’s ability and the patient’s pain tolereance.

No need for complex flap surgery…that sounds like a great selling point. The reason they market that way is the though that these “mini” implants are so small that there is no need to see the underlying bone or anatomic structures. Only with in-depth surgical imaging like a computer aided tomograph (dental CAT scan), use of computer software to pre-plan a virtual surgery and the fabrication and use of a surgical guide that is custom 3-D printed from the scan and surgical plan can this be accomplished SAFELY and EFFECTIVELY with almost 100% assurance of the implants position. That is not done in these cases. A hole is drilled to the placer’s ability and experience and the mini-implant is placed “in the dark.”

Shorter Healing Time…bone and gum heal at the same rate, regardless of the type of injury. There is no magic elixir that makes bone integrate to a mini-implant faster than a conventional implant.

No need for bone grafts…typically, this is a guess, because a flap is rarely, if ever performed, to assess the actual bone for these cases. It is highly likely that parts, or most of the implant aren’t completely in bone when they are placed, but this is never confirmed.

Mini-implant look and feel just like regular teeth…The only time this is true is in people with extremely small, narrow teeth such as the front lower four incisor teeth and the maxillary lateral incisor (next to the front two center teeth). In people with extremely limited space with minimal bite forces, mini-implants are often a good choice in those limited areas. Otherwise, in teeth with a normal diameter, the tooth becomes the equivalent of a bowling ball sitting on top of a pencil. This causes unnatural emergence profiles (how the tooth appears to come up and out of the gum tissue), and causes oral hygiene difficulty. This difficulty in adequate cleaning causes more problems such as trapped odor, gingivitis, and ultimately leads to bone loss. Conventional implants are made to mimic the diameter of the natural tooth they are replacing with home care usually being no different than it would be for the tooth it is replacing.

Mini-implants are significantly cheaper than conventional implants…Although prices vary, mini-implants are not significantly cheaper than conventional implants, and in some cases, can be more expensive. For example, to replace a molar tooth, it takes only one conventional dental implant which Blue Cross Blue Shield values at $1500. To replace the same molar with mini-implants, it requires two implants splinted together under one crown to try to approximate the force a conventional implant can absorb. Blue Cross Blue Shield values one mini-implant at $1300. So a conventional implant molar replacement would be $1500 and a mini-implant molar replacement would be $2600. Uninformed buyers don’t know this.

Number of implants needed

Molar with 3 mini-implants

Conventional single implant to replace a molar

A single Zimmer implant to replace a molar.

 

 

 

 

 

 

 

 

 

The negatives with mini-implants

Mini-implant do not emerge like conventional implants making esthetics difficult.Hygiene is difficult with mini-implants.
A doctor can take a single day course and legally begin placing them into patients the following day with no further training.
Limited angle correction.
Much higher chance of fracture in normal function.
Many doctors that place them, place significantly more than needed expecting one or more to fail. That’s not what should be an expected outcome.

Two lower incisors with mini-implants

Poor hygiene and esthetics with mini-implants

2 mini-implant incisors

2 mini-implant incisors

 

 

 

 

 

 

 

 

 

The positives with mini-implants

Are excellent for temporary anchorage or as additional anchorage in a denture case.
Are good for extremely atrophic ridge patients (small/minimal bone) who can’t have their bone rebuilt.
Are good for someone looking for a slightly less expensive option.
Are good for patients with limited space in mandibular incisor areas or maxillary lateral incisors.
Are excellent to obtain temporary anchorage in patients undergoing orthodontics that don’t want to wear headgear.

Summary

Don’t let the hype and marketing fool you when considering mini-implants. Also, go to an implant surgeon like a periodontist or oral maxillofacial surgeon who has been trained for years in the field of dental implants, bone and surgery, or minimally, a general dentist who has completed a multi-week course in dental implants. Let an experienced and qualified surgeon help educate you so you can make an educated and informed decision about dental implants and what type is best suited for your specific situation.
Just remember, when something sounds too good to be true, it usually is.

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