Dental Implants

Overview
Dental implants are replacements for missing tooth roots and thus serve as a foundation for replacement teeth which look, feel and function like natural teeth. They have created a revolution in dentistry because of the expanded treatment possibilities they provide.  Millions of people all over the world enjoy normal function and an attractive smile thanks to the availability of dental implants. Usually, when you lose a tooth it is best for your oral health to have it replaced. Missing teeth can affect your "bite" as well as your ability to speak and chew. Their loss can increase the burden on your remaining teeth and can cause muscle pain in your jaws as well as headaches. And of course, missing teeth are only cute in my 2nd graders smile; for most adults, a missing tooth in ones smile is an embarrassing problem that needs to be corrected.

History
In 1952, Prof. Per-Ingvar Branemark of Sweden conducted an experiment where he utilized a titanium implant chamber to study blood flow in rabbit bone. At the conclusion of the experiment, when it became time to remove the titanium chambers from the bone, he discovered that the bone had bonded so completely to the implant that the chamber could not be removed. Branemark called the discovery "osseointegration," and was able to foresee the possibilities for human use. Osseointegration was first utilized in dentistry for fixation of teeth and now also is used for cranial and maxillofacial reconstruction as well. With his pioneering research, Dr. Branemark opened the door to a lifetime of renewed comfort and self-confidence for the millions of individuals facing the frustration and embarrassment of tooth loss.

What is a Dental Implant?
The best way to describe a dental implant is to compare it to a real tooth, which consists of a crown and a root. The crown is the visible part of the tooth that we show when we smile, chew with when we eat, and clean when we brush.  Beneath the crown is the root, which anchors the tooth through the gum tissue to the jawbone. When a tooth is lost, both the root and the crown are missing.

Dental implants are prosthetic tooth roots made of specially treated titanium, the same biomaterial used for artificial hip and knee joints (see history above).  This titanium root is inserted into the jaw bone to take the place of the root of your missing tooth or to act as an anchor for retention of a loose denture. Once healing has occurred (healing time usually 6 to 12 weeks), your general/restorative dentist secures a crown to the top of the implant.  Recall that the crown is the top part of a tooth that is seen above the gum level.  In some cases a temporary crown can be placed almost immediately (see immediate provisionalization). The new tooth looks and performs like the original tooth.  If many or all teeth are missing, dental implants may be used to either improve anchorage and reduce denture movement or even to support a non-removable bridge! (see Teeth-In-An-Hour).

How Can a Missing Tooth Be Replaced?
A tooth or teeth can be replaced by some type of removable denture (temporary or longer lasting), a fixed partial denture (Bridge), or by dental implant supported crowns or bridges.

A temporary removable denture (aka, flipper) These are relatively fragile and designed to last for only a few months. Flippers are usually only worn by patients on a temporary basis for esthetic purposes while they are waiting for more definitive and permanent treatment.

A cast partial denture is also a removable tooth replacement. It is precision cast in metal for increased strength and is designed to last longer. Wire clasps are commonly used to hold it in place. These wire clasps are frequently visible when smiling and over time will prove detrimental to the remaining supporting teeth by which they are retained.

Full dentures (aka, plates) are an option for patients who have lost all their teeth in one or both jaws. The success and fit of a full denture depends upon the patients jaw shape and size, their oral habits, and their adaptability.  Having so much of the inside of ones mouth covered by the dentures (including entire roof of mouth) will significantly affect the ability to taste and to perceive hot or cold food.  Some people adapt well to their dentures, while other patients are not able to adapt at all.

A fixed/cemented Bridge is created by first reducing the teeth (a dental drill is used to take away tooth structure) on either side of the missing tooth space; these are called the abutment teeth.  A series of artificial crowns are then made that are cast together in a laboratory and then cemented onto the abutment teeth. Bridges have some significant disadvantages.  Though some may last throughout life, the average lifespan of a bridge is about 7 to 10 years; they are usually lost due to marginal decay (often painless) that occurs where the abutment crown(s) metal joins to the root.  Cleaning beneath a bridge is time consuming and often challenging, which accounts for the marginal decay that often eventually occurs.  Finally the reduction of the abutment teeth is not a risk-free procedure, as the pulp may be overheated, leading to the need for endodontic (root canal) treatment. Endodontically-treated teeth are more brittle and prone to fracture, which may further contribute to the early demise of a fixed bridge.

Dental implants can be used to provide support for the replacement of one, several, or all teeth. After years of research and clinical trials, this option is not only offered with confidence but in most cases is the ideal means of structural support for tooth replacement. While the implant surgery would be accomplished in our office, the implant-supported teeth are created by your restorative/general dentist. The teeth may be cemented, screw-retained, or removable (denture) and may be made attractive, stable, and comfortable for almost any patient.

Who is a Candidate for Dental Implants? 
Anyone who is missing one or more teeth or who may be unhappy with their dentures is a candidate. Age has not been shown to be a factor that affects success although radiation therapy to the area and poorly controlled diseases such as diabetes can affect the success rate. There are very few medical reasons that would disqualify a patient for implant placement. The most significant limiting factor is whether or not there is sufficient bone remaining in which to place the implant.  An estimate of the adequacy of existing bone can be determined by the clinical examination and a panoramic x-ray. In some cases a more detailed a 3-D CT scan will be indicated in order to provide more diagnostic detail.  It is often helpful when your general dentist (who will create the teeth for the implant) creates a laboratory simulation (diagnostic setup) of the ultimate position of the tooth or teeth to be replaced.  This diagnostic setup can aid in making a final determination of bone sufficiency.  If there is a deficit, then a predictable surgical grafting procedure can be accomplished that will allow dental implant placement.

Dental implants are available in a variety of lengths and widths and have different types of surfaces. Selection of the ideal implant type will depend on specific treatment needs. Once an implant has been placed in the bone, the average healing time is between 6 and 8 weeks (though as long as 4 months rare cases). When this initial phase of healing is completed, a support post called an abutment will be placed into the top of the implant by your restorative dentist.  Occasionally this second step may be incorporated into the first step and is placed at the time of implant placement.  A new crown will then be made and placed on top. If all of your teeth are missing, a variety of treatment options are available to support the replacement teeth.

Dental Implant Facts

• The most advanced tooth replacement system ever developed
• Function as well as natural tooth roots
• Are placed (& restored) in your doctor’s office with minimal discomfort
• Improve comfort and function
• Have a 95 to 98% success rate
• Can allow you to eat the foods you love and speak, smile and laugh with confidence
• Represent a conservative treatment option since they preserve adjacent (“innocent bystander”) teeth
• Can never develop decay
• Can never require a root canal
• Can provide greatly improved stability for a lower or upper denture
• Dental implant are an option for adults of all ages
• Help preserve the jawbone to prevent the appearance of premature aging

Can My Dental Implant Be Placed Painlessly?
Yes, absolutely. The most predictable way to control discomfort and anxiety is through the use of intravenous sedation (twilight sleep) or general anesthesia (complete sleep) in addition to local anesthesia / numbing injections, which are administered after you drift off to sleep. This is accomplished in the vast majority of cases in our office.  However, if only a few implants are being placed, a local anesthetic alone may be used.  Typically, the post-operative course is less painful than having a tooth removed.

What Is Involved In Placement of A Dental Implant? 

• A local anesthetic is administered to numb the area where the implant will be placed.
• Numbness is verified and a small incision is made in the gums to reveal the bone where the implant will be placed. 
• If the implant is being placed immediately at same visit as a tooth removal, the tooth root is first removed and the socket is cleaned.
• The bone site is prepared using special instruments and the implant is placed.
• If the implant is being placed outside the smile zone (not easily seen when you smile), then a temporary titanium cover is placed in the top of the implant.
• If implant is being placed within the smile zone, then a previously-prepared prosthesis (artificial crown) can be placed. In some cases an immediate temporary bridge is placed (see Teeth-In-An-Hour).
• The implant will need to heal to the bone for two to four months in most cases.  Actual healing time will be determined by a variety of factors.
• At least one follow-up appointment will be needed to ensure that your mouth is healing well.
• Your general dentist creates the final crown for the top of the implant.

Can a tooth be removed and a dental implant placed at the same visit?

Provided the bone is healthy and there is no infection, immediate implant placement is predictable for all teeth except the molars (in the very back of your mouth).  An incisor or premolar tooth can usually be removed and an implant immediately placed in that socket. Besides shortening the total treatment time, this option serves to preserve the shape and volume of gum tissue and bone in the area. However, immediate implant placement into an extraction socket is not as predictable for the multi-rooted molar teeth, though it can be accomplished 10 to 20% of the time.  In the remainder of cases the tooth is removed and the socket is often grafted in order to preserve the bone for future implant placement. The graft material turns into bone after 3 to 4 months, and then an implant can be placed.

Is it possible for a temporary crown to be immediately placed on the dental implant?

Placing a temporary crown immediately after implant placement is possible.  However, the crown cannot be used for chewing food and must be left out of occlusion (meaning that it does not contact a tooth in the opposite jaw), since any force applied to the crown would traumatize the implant and prevent healing. Indeed, such a crown is placed for esthetic purposes only, and not for chewing. This option is typically limited to the upper front teeth and is only feasible if your bite allows it.  Although this immediate temporization is desirable for obvious reasons, it carriers certain risk to the implant that sometimes are not worth taking.

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Bone Grafting

Overview
Over a period of time, the bone in the upper jaw and lower jaw will melt away if a tooth is missing or affected by an infection such as periodontal (gum) disease.  This often leaves a condition in which there is poor quality and/or quantity of bone suitable for placement of dental implants. To replace the lost bone, which is needed for the dental implant, we use a variety of bone grafting techniques. This not only allows us the opportunity to place implants of proper length and width, it also gives us a chance to restore the tooth to its original function and aesthetic appearance. The following bone grafting procedures have been used with success.

The Socket Preservation Graft
Conservative surgical technique at the time of tooth removal can minimize the degree of bone loss and provide a better cosmetic and functional result whether a tooth is to be replaced with a bridge or an implant. The socket preservation graft is indicated when a bone socket wall is thin and the likelihood of volumetric bone loss is high; this graft is used immediately after a tooth is removed. The bone is typically of bovine (cow) source and is a protein-free source of calcium and phosphate mineral; the bone mineral is condensed into the root socket/opening.  During healing the graft mineral serves as a scaffolding for the bodys bone-forming cells (osteoblasts) to use and ultimately is dissolved away and replaced with new bone.  A collagen plug (also bovine) is placed over the bone mineral graft. Use of this preservation graft will typically result in a better site for the future implant placement since the normal architecture of bone and soft tissues is preserved to a greater extent.

Block Cortical Bone Graft
In some cases the width and height of remaining bone are insufficient to place an implant in the proper position. Restoration of the lost bone is necessary in order to allow correct placement of the implant. This is especially common at sites where a permanent tooth never developed (congenitally missing) or where a bridge has been worn for more than a few years.  Bone must be donated from another area of the jaw, typically from the third molar area and then placed in the recipient area of insufficient bone volume.  Autogenous (the patients own) bone is the best type of bone to use in these cases.  The block graft is secured in place with small temporary titanium screws.  The donor bone graft is allowed to fuse to the recipient site for 4 months.  At the time of implant placement, the temporary screws are removed.

Sinus Lift Bone Graft
This procedure is utilized to replace missing bone to allow for implant placement in the back of the upper jaw. A small window is made on the side of the upper jaw (maxilla) under the tissue to expose the maxillary sinus membrane. The membrane lining the sinus is elevated and a bone graft material is added under the membrane.  The tissue is closed over the window and allowed to heal. In some cases a dental implant(s) may be placed simultaneously but in other cases, placement must be postponed until the graft has healed.  The bone graft material will form new bone within about 3 to 4 months. 

Guided Bone Regeneration
Guided bone regeneration may be utilized when there is a localized defect in the bone or only slightly inadequate bone in the area of implant placement. The patients own bone is often used in combination with bovine bone mineral and recombinant Bone Morphogenetic Protein.  This bone graft is then covered with a titanium mesh barrier membrane that allows nutrients to gain access to the area but preserves the grafts shape.  The graft bone is then turned into native bone over a period of approximately 4 months.

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Wisdom Teeth

What are Wisdom Teeth? 
Officially referred to as third molars, they are usually the last teeth to develop and are located in the back part of your mouth. Their formation is usually complete between the ages of 15 and 20, a time traditionally associated with the onset of maturity and the attainment of wisdom.

What are Impacted Wisdom teeth?
Since they are the last to develop, they may not have enough room for the wisdom teeth to grow into the mouth and become fully functional teeth that can be cleaned and cared for.  When this occurs, they are said to be impacted in one of three ways.  (1) Soft Tissue Impaction: there is not enough room to allow the gums to retract for adequate cleaning of the tooth. (2) Partial Bony Impaction: bone is covering 50% or less of the crown of the tooth.  (3) Complete Bony Impaction: bone is covering more than 50% of the crown of the tooth.

Should I have Impacted Teeth removed?
Most youngsters (less than 35 years old) should, because it likely that one or more problems will occur. The most common problem is an infection of the gums overlying the tooth.  This infection is usually quite painful and has been known on occasion to spread into the throat and neck, requiring hospitalization.  Other common problems that may occur include a painful cavity (decay) in the impacted tooth and/or damage to the roots or gums of adjacent teeth.  More serious problems may occur if the sac surrounding the impacted tooth becomes filled with fluid and enlarges to form a cyst. As the cyst grows it may hollow out the jaw and permanently damage adjacent teeth, the surrounding bone and nerves. Rarely, if a cyst is not treated, a tumor may develop from its walls and a more serious surgical procedure may be required to remove it.  In addition, impacted teeth may cause headaches, earaches, and possibly crowding of other teeth and orthodontic relapse.

Infection	Decay/root damage	Cyst formation

What If I Don't Have Them Removed When I Am A Teenager?
When impacted wisdom teeth are not removed in the teen years or early twenties, the problems listed above are likely to occur later in life. When it becomes necessary to remove these teeth in the 30s, 40s, or beyond, then it is more difficult for the patient.  With each passing year, the normal process of aging dictates that our bodies naturally become a little less proficient in healing wounds and managing minor irritations and infections.  Wounds in the mouth are a special challenge to our bodys wound-healing system, as they are bathed in saliva, bacteria, and food material!

If I Am Over 35 Years Old, Should I Have Them Removed Now? 
The predictability of healing decreases with age and the likelihood of infection and delayed healing increases.  In some cases, it may be advisable to observe one or more of the teeth rather than remove them, assuming that one of the problems listed above is not already present.  The final decision is made on an individual basis.  An examination and a recent (less than one year old) panoramic x-ray will enable Dr. Worley to properly advise you.  If the decision is made to observe the wisdom teeth, then a panoramic x-ray and examination should be repeated at least every 3 years indefinitely.

What If The Wisdom Teeth Are Not Impacted? 
If they have grown into a functional and cleansable position, they may be retained  However, since they are so close to the throat, most patients have difficulty brushing and flossing around them (due in part to the gag reflex).  Thus, cavities and gum disease are common problems with non-impacted Wisdom Teeth.  In addition, research has shown that older patients may be at greater risk for disease, including periodontitis, in the tissues surrounding the third molars and adjacent teeth. Periodontal infections, such as those observed in this study, may affect your general health.

What Happens On The Day That They Are Removed?
Anxious patients may be given a prescription for a calming medication to take on the evening prior to and on the morning of the appointment. The surgery will usually take place in the office.  In the vast majority of cases, it is necessary that intravenous medications be used to administer a safe, light general anesthesia so that you can remain comfortable and the surgery can be completed as safely and efficiently as possible.   Plan to spend the rest of the day at home, with a responsible adult available to assist you should the need arise. 
What Happens Afterwards?  What Will I Feel Like?  Reactions to surgery vary from person to person, but the vast majority of our patients tell us how pleasantly surprised they are that their discomfort was so reasonable; most patient only need Ibuprofen (Motrin, Advil, Aleve) to keep them comfortable during the day, supplementing this with prescription pain medication before bedtime as needed. Discomfort peaks on the second or third day after surgery and rapidly resolves thereafter. By five days, most patients feel that they are “over the hump and back to normal. You will be given detailed written and verbal post-operative instructions.

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Orthodontic Exposure of Impacted Teeth

When primary teeth (baby teeth) are lost, in most cases they are replaced by adult (secondary) teeth. Occasionally an adult tooth has insufficient room to erupt into the mouth or forms at an angle that doesn't allow it to erupt properly. When this occurs the tooth is said to be impacted. The teeth that most commonly become impacted are the third molars (wisdom teeth). Click here for more information on wisdom teeth  The treatment for impacted wisdom teeth is usually removal. However, other teeth that are important to normal chewing function can also become impacted. Of these teeth the most common are the upper canine teeth (eye teeth). In order to secure the function and esthetic appearance of these important teeth, we can surgically expose the teeth, which will allow your orthodontist to slowly guide them into position.
The surgical procedure is performed in the office.  The gum tissue that is covering the impacted tooth will be lifted up to expose the hidden tooth underneath. If there is a baby tooth present, it will be removed at the same time. Once the tooth is exposed, an orthodontic bracket will be bonded to the exposed tooth's crown. The bracket will have a miniature gold chain attached to it. The oral surgeon will guide the chain back to the orthodontic arch wire where it will be temporarily attached with a suture.  Sometimes the surgeon will leave the exposed impacted tooth completely uncovered by suturing the gum up high above the tooth or making a window in the gum covering the tooth.  Most of the time, the gum will be returned to its original location and sutured back with only the chain remaining visible as it exits a small hole in the gum.
Shortly after surgery (1 to 14 days) the patient will return to the orthodontist. An elastic band will be attached to the chain to put a light pulling force (traction) on the impacted tooth. This will begin the process of moving the tooth into its proper place in the dental arch. This is a carefully controlled, slow process that may take up to a full year to complete. Remember, the goal is to erupt the impacted tooth and not to extract it! Once the tooth is moved into the arch in its final position, the gum around it will be evaluated to make sure it is sufficiently strong and healthy to last for a lifetime of chewing and tooth brushing. In some circumstances, especially those where the tooth had to be moved a long distance, there may be some minor gum surgery required to add bulk to the gum tissue over the relocated tooth so it remains healthy during normal function.

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Oral Pathology
The inside of the mouth is normally lined with a special type of skin (mucosa) that is smooth and coral pink in color. Any alteration in this appearance could be a warning sign for a pathological process. The most serious of these is oral cancer. The following can be signs at the beginning of a pathologic process or cancerous growth:

• Reddish patches (erythroplasia) or whitish patches (leukoplakia) in the mouth
• A sore that fails to heal and bleeds easily
• A lump or thickening on the skin lining the inside of the mouth
• Chronic sore throat or hoarseness
• Difficulty in chewing or swallowing

These changes can be detected on the lips, cheeks, palate and gum tissue around the teeth, tongue, face and/or neck. Pain does not always occur with pathology, and curiously, is not often associated with oral cancer. However, any patient with facial and/or oral pain without an obvious cause or reason may also be at risk for oral cancer.

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Teeth-in-an-Hour
This is a revolutionary concept that can prove patients with fully functioning teeth on dental implants in one single procedure that lasts a little over an hour. This technology was recently developed by Nobel Biocare, and allows for collaboration between both the restorative doctor and the surgeon.

This merging of knowledge and experience achieves not only increased safety, but also a more precise implant placement. In addition, the fabrication of a final prosthesis is completed prior to the surgery. The computer-guided implant surgery is done without requiring any flap reflection. This benefits the patient being that there is less post operative discomfort, less swelling and less bruising. Often, patients can resume their normal activities the next day. The process starts when a 3-D CAT scan is made of the patient's jawbone(s). This CAT scan allows for the generation of a 3-D virtual model of the jawbone, which can then be used in virtual reality software to plan the implant placement without the presence of the patient (Virtual Surgery).  This results in more accurate implant placement and less chair time for the patient at the surgery office.

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