SECTION 2 – THE EVOLUTION OF IMPLANT DENTISTRY
Q: Somebody said awhile ago something about implant surfaces and tissue responses. Basically the comment was, "rough is good for bone but bad for soft tissues." Smooth is good for soft tissues but bad for bone. I've seen that this may be true. Can somebody provide a physiological explanation for that?
A: When hard tissue grows into the irregularities of a rough surface, it provides greater attachment strength, as measured by torque tests. This may also be attributed to the greater surface area created by the rough surface. Greater attachment strength means a greater ability of the implant to carry load and withstand micro-movements during initial healing that could interfere with osseointegration. A rough surface also provides greater attachment area for soft tissue, which improves attachment. Since the soft tissue is exposed to the oral environment through the gingival sulcus, the rough surface can contribute to plaque accumulation. This could cause soft tissue inflammation that is deleterious to the attachment and healing of the soft tissue. A smooth surface encourages undesirable bone loss. Since we can not predict exactly how much the bone will recede, we cannot know what portion of the implant will be exposed to either the soft or hard tissue. This is why Paragon created Dual Transition Selective Surface with a smooth 1 mm collar, a 2 mm medium-rough (SBM) blasted zone (good for hard or soft tissue) and below this, HA or TPS. We also have implants with SBM surface only that provide greater bone attachment than a machined or acid-etched surface. SBM will not be a problem if it becomes exposed to the soft tissue and it provides more surface area for soft and hard tissue attachment.
Q: When HA is exposed to soft tissue, the results can be catastrophic failure, at least on the dental level. When other relatively rough surfaces become exposed to soft tissue, we really do not know what problems, if any, we will have...Wouldn’t you agree that the part about rough surfaces being good for bone adaptation and smooth surfaces being poor is bunk?
A: I suggest that this doctor read the literature before dismissing as "bunk" facts that are well documented, such as rougher surfaces increasing bone attachment (Wennerberg, Buser, Bowers, Block, etc.). As for HA being disastrous if exposed, I suggest that he read the VA Study results published in JOMS (1998;56:1302–1311) documenting a 97% success with 1700 HA coated implants with 3-5 year follow-up. All of these Paragon implants had the HA exposed because they were older designs that only had a 0.5 mm metal collar, and the average bone loss was over 1.5 mm. Only 4% of these implants had soft tissue complications compared to 2% for non-coated implants. This doctor further stated: "The manufacturers think they have all of the answers, but they are just trying to sell their products...What is the point of manufacturers doing research if people like this doctor are not influenced by facts?
Q: You have to separate here what the research is really saying at this point in time from what the manufacturers are claiming. Isn’t it really apples and oranges?
A: I have to agree with this one. Straumann switched from TPS to SLA and are claiming earlier loading. In fact, the animal studies they cite, Cochran and Buser, do not show any significant difference in osseointegration between the two surfaces. Straumann changed to the SLA surface to avoid the rough TPS becoming exposed and causing soft tissue problems, since they extended the TPS to the crest of the ridge. Straumann couldn't admit this was a mistake, so they switched to a blasted/etched surface without interconnecting pores of TPS and used the excuse of faster healing to justify the change. 3i just used the acid etching process, which actually makes the machined surface smoother, and then cites a number of studies of rough, blasted surfaces to justify their claims of increased bone attachment. Now they claim earlier loading, which they attribute to their Osseotite surface without any comparison studies of machined surfaces side-by-side to support this claim.
I am slowly getting to use as many different implants as I can to satisfy
my own curiosity as to what is out there.
A: While that may be true in the hands of an experienced clinician in good quality bone, the VA study shows definite differences between acid-etched and HA-coated implants, with implants of the same design placed side-by-side in the same patient. SO, THEY DO NOT ALL WORK THE SAME! For example, in the maxillary edentulous jaw, HA Screw-Vents had a 94%, 3- to 5-year survival rate compared to only 72% for acid-etched Screw-Vents. HA coated press-fit implants in the maxillary posterior had a 97% success rate after 3-5 years, while Brånemark’s machined implants had only 87% in the maxilla, according to an article by Friberg.
As far as the development process of the implants, you must still understand
that, while innovation is great, one of the most compelling critiques
of the Core-Vent/Dentsply/ Paragon systems is that they have changed
and changed and changed. Dentists do not want so much change so fast,
even if the innovations are great! For instance, what are you going
to tell those dentists who invested in the now-obsolete COMPLETE IMPLANT
parts and components? The other companies have not changed so many parts
and pieces so rapidly that they obsolete their product line or make
them so cumbersome that they appear confusing to many dentists. And
what was wrong with the healing collar packaging? It had so many parts
it confused many, but it was and is still an excellent way to deliver
either one- or
Thanks for taking the time to direct my focus on the rationale behind
my marketing and product design strategy.
I am reading a book entitled, The Discipline of Market Leaders. Its thesis is that there are three types of business strategies:
1. Customer intimacy - cultivate relationships through customer service (e.g. Nobel Biocare)
2. Low prices - (e.g. Lifecore — started with low prices, but now has a high list price while making whatever deals it takes to get the sales)
3. Product leadership: "an offer of the best products, period. Moreover, product leaders don't build their positions with just one innovation; they continue to innovate year after year, product cycle after product cycle." (i.e. Paragon)
The book also states that a "company must first decide where it will stake its claim in the marketplace and what kind of value it will offer its customers. Then it can identify core competencies and reengineer the processes that make up the operating model required to get the job done."
As far as customer intimacy is concerned, it takes too much money and time to stroke the opinion leaders. Many are looking for the prestige that comes with being a spokesperson for a large foreign company, and the money they offer in exchange for their expressed "opinions" that make up for their products’ shortcomings.
Paragon is focusing on offering the best customer service through investing in knowledgeable staff, state-of-the-art on-line ordering, good manuals and organized, simplified products. At $121-$143 an implant with many additional product advantages, the Taper-Lock implant allows me to maintain a premium-priced product line without having to negotiate discounts as other companies do.
I am clearly the market leader in product innovation because I am not afraid to obsolete my own products, rather than wait for the competition to do so. Paragon's "core competencies" include state-of-the-art manufacturing, engineering and an understanding of how design impacts performance. No other company has a single owner that is knowledgeable in material sciences, clinical dentistry and has the total authority to redirect the manufacturing resources as changes in technology or industry demands dictate.
A perfect example of this is Paragon's response to the introduction of the double lead, tapered Mk IV implant from Nobel Biocare. Once they articulated the advantages of this implant, thereby creating a market for it, I jumped in and did an end-run around them with triple lead threads on a tapered implant for insertion into a straight hole. Both of these features where already covered by Paragon patents and Nobel Biocare has been put on notice of infringement. Furthermore, I then combined the advantages of both the Healing Collar Packaging and the Complete Implant by inventing an Implant Extender, packaged with the AdVent implant. Its large internal hex will better compete with the ITI implant that requires two neck lengths and five different heights of cap screws to do what the one prepackaged AdVent implant can do. The added advantage of the AdVent is that it will allow Paragon to eliminate more than twice as many parts as it adds, which will reduce backorder problems, as well as our manufacturing costs.
As for the Complete System being obsolete, all the same drills and tools work with the AdVent implant. A new, stronger hex tool will be made, but the one for the Complete Implant and Healing Collar Packaging works. The AdVent offers many advantages that warrant the change. The Complete Implant, while interesting enough to open some doors and get some interest, did not light the fire I thought it would. Furthermore, its applications were limited to the non-esthetic zone and a one-stage protocol. The Healing Collar System was good but not much better than attaching a healing collar at time of placement. With the one-piece healing collars, the restorative dentists could detach them without special tools.
The industry is moving towards one-stage surgery. The AdVent once again says to the profession that Paragon continues to take a leadership role in innovation and to that extent, reaffirms our position as the industry leader in innovation.
To the vast majority of "late
adopters" still stuck on Nobel Biocare or other external hex implants,
hopefully the pricing and features of the Taper-Lock will get them interested.
Our CD-ROM program attempts to educate dentists to be more discerning
and aware that not all systems are equal. The fact that Paragon is the
only company providing this competitive information should say to dentists
that we understand their concerns, we have the answers and we are not
afraid to compare our products to those of the competitors. Our case
registration program gives the surgeon an easy way to provide the information
my staff needs to contact the restorative dentists and guide them through
the abutment selection process. This one-on-one level of customer service,
unprecedented in the industry, eliminates the need for my salespeople
to run around holding the hand of every GP. The Paradigm Shift concept
also eliminates the need of the referring dentist to know what implant
the surgeon used prior to selecting/attaching abutments. If the surgeon
attaches the abutments, there are no new parts or procedures for the
referring dentists to be concerned about with our system. Surgeons no
longer have to spend time hand-holding their restorative dentists—Paragon
will do it for them with the case registration program.
Q: Please explain the difference between the AdVent and the Complete implants. I noted that the AdVent requires different drills than the Complete. Please explain the various drills. Also, the abutment connection platform for the AdVent appears to be different from the Micro-Vent. Does that mean that the AdVent is a totally different implant and, consequently, requires different surgical and prosthetic armamentaria?
A: I began development of the one-stage implant in 1993. My first effort was a two-piece, two-stage, Screw-Vent implant with Healing Collar Packaging rather than Fixture Mount/Transfer Packaging. The 4mmL healing collar was internally hexed and designed for easy implant insertion. After osseointegration, the healing collar could be converted into an abutment by attaching a ball or tapered abutment screw. The healing collar could also be removed and replaced with a standard preparable abutment for esthetic, subgingival margins.
In 1997, I introduced the Complete implant, adding 3.5 mm to the top of the implant and duplicating the platform of the standard Brånemark abutment. The idea was that in areas where esthetics did not demand the ability to remove the collar, why not make it a permanent part of the implant to serve as an abutment? The shortcoming of this implant was that, in duplicating the Brånemark abutment platform, I had to use a small fixation screw. I prefer over-engineering a system, so I was looking for a better way to accomplish my objectives.
In 1999, I introduced the AdVent, which combines the best features of the two-piece, two-stage, implant with Healing Collar Packaging and the Complete implant into one design. The AdVent has a 3mmL extended collar with a 1mmL tapered top, allowing the margin of the restoration can be further extended below the soft tissue. The AdVent platform has a large, 3mmD internal hex with a lead-in bevel. Although the wide Micro-Vent implant also has a 3mmD internal hex, its platform is different from the AdVent’s. This internal hex allows attachment of a much stronger screw than was possible with the Complete implant. Furthermore, the AdVent’s platform was designed so that a ZAAG female titanium housing can be screwed in, providing a low-profile overdenture attachment.
The Complete implant’s cover screw added another 1.5mm to its 3.5mm attached collar. The AdVent implant, with its internal hex, uses a low profile cover screw that adds nothing to its overall height. The AdVent’s low profile cover screw allows the implant to be countersunk 2mm for a two-stage surgical protocol, if that is what is desired. The AdVent is also packaged with a 2mmL Implant Extender that can be placed at the time of stage-one surgery. Once the implant extender has been attached, it projects up though the tissue to allow for a one-stage surgical protocol. This works like the one-stage protocol of Healing Collar Packaging, but with an esthetic, subgingival margin to the restoration.
Another advantage of the AdVent implant over the Complete implant is its tapered body. Designed for insertion into a straight and slightly undersized osteotomy, its tapered body provides increased stability in soft bone through bone compression. This unique feature also allows for the elimination of a narrow 3.3mmD implant, which leaves only the 3.7 and 4.7mmD implants — both with the same 4.1mmD platform. The AdVent implant also features triple lead threads for faster insertion. Despite their differences, however, both the Complete and AdVent implants require the same drills and insertion tools.
In January 2000, Paragon will introduce the new Tapered Screw-Vent two-stage implant with triple lead threads, just like the AdVent implant. It will be available in 3.7mmD, 4.7mmD and 6.0mmD with the same three available platforms as the current Micro-Vent2 implant. Its tapered body eliminates the need for a 3.3mmD Tapered Screw-Vent, since the 3.7mmD Tapered Screw-Vent can be inserted into a socket prepared in a narrow ridge for a 3.3mmD implant by expanding the bone as it’s diameter widens from 2.7mmD to 3.7mmD during the insertion process.
The new Tapered Screw-Vent, like the AdVent, will feature Paragon’s patented dual transition surfacing. The HA-coated implant includes a 2mm blasted (SBM) zone at the crest of the ridge. The Tapered Screw-Vent will also be available with just the SBM surface. New step-down drills will be available for inserting the implant into dense bone, assuring bone engagement by the narrow apical threads during final seating. When drilling in soft bone, surgical protocol requires the preparation of an undersized osteotomy. This is achieved by simply using what has traditionally been the intermediate drill (2.8mm for 3.7mmD implant; 3.8mm for 4.7mmD implant) as the final drill. Ideal for use in soft bone and narrow ridges, good bone contact is achieved throughout the length of the tapered implant, even when inserted into a socket prepared with a straight drill. This can also be accomplished with the current straight drills by penetrating to the score line that corresponds with the implant length with the intermediate drill, then stopping one score line shorter with the final drill to create a stepped-down osteotomy.
Q: Given the wide variety of implant options from Paragon, what do you see as Paragon’s main implants in 2000 and beyond.
A: On rare occasions, new technology will provide a wake-up call to an entire industry. The need to achieve immediate fixation in soft bone, the dilemma of inserting an implant into narrow ridges, components that provide adequate strength, and the solution to repeated screw loosening have long challenged implant manufacturers. The desire for simplified surgical protocols, including self-tapping insertion and a one-stage surgical protocol that provides the esthetics of a two-stage implant, can be added to these clinical requirements. For implant dentistry to be a viable alternative to conventional dentistry, implant systems must provide versatile prosthetic applications with a minimum of components, complexity and cost. Paragon's AdVent and Tapered Screw-Vent implants provide viable solutions to these needs, and thus herald a new era in dental implant technology and innovation.
AdVent and Tapered Screw-Vent implants share several patented features that transform the quality, ease and long-term predictability of implant restorations:
ADVENT OFFERS ONE- OR TWO-STAGE SURGERY
Esthetic dental implant restorations require the ability to provide subgingival margins for a natural-looking emergence profile. This generally necessitates placement of a two-stage implant. When esthetics is not a primary concern, a one-stage protocol eliminates the uncovering surgery and shortens treatment time. Corresponding surgical trauma is greatly reduced, which can make implant therapy more acceptable to some patients. AdVent implants include a patented Implant Extender, which can be used as a transmucosal extension for one-stage surgery, or as a healing collar for a two-stage procedure. Surgical specialists can select the protocol of choice at the time of surgery. The AdVent's Implant Extender packaging thus reduces costs by eliminating the need to purchase a healing collar or to maintain a large inventory of both submerged and nonsubmerged implants.
THE TAPERED SCREW-VENT’S FIXTURE MOUNT/TRANSFER PACKAGING
With three diameters of 3.7mm, 4.7mm and 6mm, the Tapered Screw-Vent offers the versatility needed to optimize use of available bone. Each diameter option has its own platform diameter, 3.5mm, 4.5mm and 5.7mm, respectively, which provides the dimensional options for esthetics and immediate tooth replacement throughout the entire arch.
All of Paragon's implant products are made in the U.S.A