THE HISTORICAL BACKDROP
The
Chinese might have pulled it off, except that soon after the voyages of Admiral
Cheng Ho, they fell into the “Middle Kingdom” mindset that closed off the rest
of the world, having decided that they had nothing to learn from the rest of
the world. From that point onwards, it was a steady decline.
During
the rise of Islamic Civilization, great learning in every field of science
ranging from medicine, mathematics , astronomy etc. developed, and the
Europeans and many others from the then known world came to learn from them.
But this rise of learning and discovery somehow
also faltered.
The
Europeans went through their dark ages when most thinking and ideas were
dictated by their political and religious leaders. The Renaissance brought
about a renewed surge and determination to use reason and logic to tackle every
field of knowledge and endeavour. And we are still feeling the effects today.
So “the dream come true” has emerged from
the great upsurge of logical thought and reasoned understanding of Mother
Nature. Science has enjoyed a heavy emphasis since then and in the last century
has been diligently applied to the science of healing of the mouth, teeth and
body. The dream of mankind to replace a lost tooth with something as good as
before if not better was pursued with renewed vigor and enthusiasm, this time
with a reasoned, logical and scientific approach.
Dental
implants stumbled from one material to another, stainless steel screws,
porcelain inserts, glass, ivory, bone, stone etc. were all tried and used. The
mainstay in ideas and design seemed to be the use of metals like gold, chrome
cobalt and steel of various types with all types of designs ranging from screws
and cylinders and spikes and frameworks that rest intimately on the surface of
the bone.
INNOVATORS IN DENTISTRY
Historically,
innovators in dentistry like in most other disciplines were practitioners who
pushed the limits of treatment. But those who dare to try something not tried
before has always been frowned upon. And rightly so, since we are treating
human beings and not inanimate objects.
Those who want to do new things must approach it with care, compassion and with
all the science available at the time and place.
When
fixed partial dentures [read bridges] were introduced in the 1900s, it was
vehemently opposed by the profession. They caused innumerable health problems
because they were poorly made and placed. Not until decades later, when
anatomic form, occlusion, physiologic principles and ceramics were introduced
did they become as successful as it is today. The idea was excellent, but the
supporting science was inadequate. All it required was a corresponding
improvement of applied science before it proved to be viable and successful.
And this success has laid the groundwork for the success of oral dental
implants today.
Proponents
of implant dentistry also ran through the same gauntlet, and just barely 20 to
30 years ago, the mention of the word “implant” alone was stared at with deep
frowns by the conservatives of the day. And rightly so, because conservatives
have their uses and radicals have their uses. Liberals, leftists and even
extremists give check and balance and allow the whole behemoth of the world of
dentistry to wobble forward steadily and surely. Linkow and Branemark, now
feted as heroes of dentistry were during their days of pursuing their vision
and experimentation, labeled as mad and crazy and even irresponsible.
With
this perspective in mind, while examining every innovation with a careful,
analytical, and critical scientific mind, we should also at the same time
discipline ourselves not to jump to conclusions and make premature judgments on
a procedure or innovation that may eventually prove successful and a boon to
many.
THE DEVELOPMENTS
Archaelogical
diggings have revealed the presence of crude tooth implants made of bone or
stone stuck to the lower jaw of homo sapiens. Records have shown that the
ancient Chinese, Egyptians, Incas all practice some form of root form implants
dating back to 4 to 5 thousand years ago.
Strock
in 1939 used vitallium screws as
dental implants. Dahl of Germany
in 1943 developed button inserts for stabilizing full upper dentures. These
were intramucosal inserts. Goldberg
and Gershkoff in 1946 designed and used a metal framework that rested
intimately on the surface of the bone and were called subperiosteal implants which proved to be reasonably successful
giving up to 90% success at 5 years but fell to 65% after 10 years. Behrman and
Egan in 1953 used magnets implanted
into the jaws to hold the dentures in place. Sollier and Chercheve in 1953 used transosseous implants for the lower anterior jaw that went from the
lower border of the mandible upwards right through to emerge in the upper
border of the edentulous mandible in order to hold the dentures. Linkow in 1969
reported his results in using blade
implants that basically formed a type of false periodontal ligament made up
of scar tissue that worked for as long as they did not get infected! Roberts
and Roberts in 1970 gave their results using the ramus frame implant that inserted into the mandible at three
points: the mandible symphysis and the left and right retromolar areas.
THE DEFINING MOMENT
The
defining moment for the dream to come true came in Toronto , Canada Sweden , with great trepidation,
presented the results of his systematic long term prospective studies of what
he called “osseointegration” especially in relation to replacing a lost tooth
almost as good as new. It has to be recorded that at the last minute, he became
so distraught and fearful of a hostile response that he almost pulled out of
the conference completely. Thankfully, he did not. The significance of his
presentation in Toronto
caused at first a ripple in the global dental community. When the implications
set in, it began a massive alteration of how we do dentistry especially in our
treatment planning and our standards of care in oral rehabilitation of a
compromised mouth and teeth. Today, we are witnessing a tsunami of oral implant
manufacturers and products and realizations that the way we should do dentistry
has changed radically and irreversibly as a result of osseointegration! Texts
on the various disciplines of dentistry ranging from oral surgery to
orthodontics etc. have to be rewritten substantially as a result. Though there
has been various claims as to who really did discover osseointegration and the use of root shaped implants, the credit
has to be given to Branemark for systematically documenting and experimenting
on the concept for two decades or more before publishing and sharing his
prospective studies to all and sundry.
His published findings gave dentists everywhere the confidence and scientific
basis to develop and use dental implants to the level that we see today. And
still the industry is growing by leaps and bounds globally . Osseointegration
has integrated into mainstream dentistry and is here to stay. The promise of tooth germ implants will take a while
yet before it can become as practical as osseointegrated titanium dental
implants has already become today.
THE SIGNIFICANCE
The significance of Branemark’s revelations
become even more clear when compared against
the “Harvard Consensus on Dental Implants of 1978”. The National Institutes of Dental Research in
the USA
brought together clinicians, researchers and professors of dentistry who decided
together that in order for a dental implant to be considered successful, it
should provide functional service for 5 years in 75% of cases. The objective
criteria developed then were:-
- Bone loss no greater than one-third of the vertical height of the implant
- Good occlusal balance and vertical dimension
- Gingival inflammation amenable to treatment
- Mobility of less than 1mm in any direction
- Absence of symptoms and infection
- Absence of any damage to adjacent teeth
- Absence of paraesthesia or anesthesia or violation of the mandibular canal, maxillary sinus, or floor of the nasal passage
- Healthy collagenous tissue
We
can see now that these esteemed professionals had far underestimated what human
ingenuity can do! Today, all these criteria has been surpassed and not only
that , the success of osseointegration has raised the benchmark of what
constitutes a successful dental implant . The wonderful thing is dentists today
routinely meet and exceed all these criteria when using and dispensing dental
implants to patients all over the world.
CONCLUSION
While
we do want to trumpet ourselves as one of possibly only two elite groups of
health professionals[the other being the opthalmologists who routinely place
lens implants successfully] who has
succeeded routinely to replace an important organ[tooth] almost as good as new
with a synthetic substitute and without the need to mess around with trying to
suppress the immune system to prevent rejection and so on, we need to caution
ourselves to practice this discipline of dental implantology responsibly and
ethically and always pushing the envelope of excellence and economy as
optimally as possible especially in the context where we are. The day is fast
approaching when dental implants will be placed routinely in every dental
clinic just as routinely as we do a filling.
Dr.
Chow Kai Foo 21st May 2007
REFERENCES
1.
Contemporary Implant Dentistry by Carl
E. Misch
2. Dental Implantology Tufts
University
3. A Matter of Balance by Elaine Williams
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