Dental Implant

 

Dental Implant had come a long way. Within the past 25 years, the simplicity in the placement of dental implants have led it to be a safe and desirable alternative in replacing missing teeth.

 

Dr. Jin has been placing Dental Implants since 1996 with excellent success rates.  Now with a wide range of available options, it give us a variety of new ways in treating and replacing lost tooth (teeth).

 

Benefits of Dental Implants

When compared to fixed bridges and removable dentures supported by other teeth or gum tissue, implants offer numerous advantages:

 

1. Preserving natural tooth structure:

Often the preferred method of replacing a single missing tooth is a bridge. Bridges require extra preparation for the surrounding teeth to ultimately connect 3 or more teeth. This negatively impacts your health by making the task of retaining your teeth more difficult and by often requiring the destruction of existing tooth structure to create room for the new bridge. An implant is mostly an independent unit and does not negatively affect the adjacent teeth.

 

2. Reduction of bone resorption:

When a tooth is lost, the supporting bone structure gradually recedes. Placing an implant in that empty space significantly reduces the speed of bone resorption and provides stability for this valuable tissue.

 

3. Retention:

Patients who have experienced removable full or partial dentures know that keeping their dentures in place is always a challenge. Dental implants offer a great improvement to denture retention for all patients. In some cases the denture can be secured to a group of implants with special screws that stabilize the denture completely.

 

4. Better esthetics:

Since implants are placed in the gum similar to the way a natural tooth is supported, they offer a more realistic and natural look compared to other alternatives.

 

Our team of dentists will evaluate your situation and assess if you are a candidate for a particular type of dental implants. Typically a series of x-rays, Pano, and/or CT-scan are performed to determine the most ideal treatment as well as to verify the size and kind of implant that should be placed.

 

Implant Phases:

Basically there are 2 phases: Surgical and Restorative.

 

Surgical Phase:

During the surgical phase, your surgeon will place a titanium-based cylinder that generally replacate the size and shape of your missing root. Once the implant is properly placed, a cover piece will be tightened over the access port of the implant to prevent gum tissue from growing into the access port.  After a period of healing time, the surgeon will then remove the cover piece and place an abutment into the access port.  This abutment represent the connecting suprastructure for the crown.

 

Restorative Phase:

Once your healing is complete, you will return for the abutment as described above.  After the abutment is placed, a series of impressions will be taken and forwarded to dental laboratory for final restoration.  Your final restoration will be adjusted for fit and permanently placed on the implant.

 

For more detail, the following is what Wikipedia said about implants.

 

 

According to Wikipedia, a dental implant is a "root" device, usually made of titanium, used to support restorations that resemble a tooth or a group of teeth that are missing.

 

Virtually all dental implants placed today are root-form endosseous implants, They appear similar to an actual tooth root and are placed within the jaw bone. Osseointegration is the fusion of the implant surface with the surrounding bone. Dental implants will fuse with bone, however they lack the periodontal ligament, so they will feel slightly different than natural teeth during chewing.

 

Dental implants can be used to support a number of dental prostheses, including crowns, implant-supported bridges or dentures. They can also be used as anchorage for orthodontic tooth movement. The use of dental implants permits directional tooth movement without reciprocal action.

^Top     Next>

Implant consent forms

Post-surgical information

Mandibular anterior implant graphic

Before and After Photos

bicuspid implant
Use of surgical stent in dental implant surgery

Dental Implant Composition:

A typical implant consists of a titanium screw with a roughened or smooth surface. The majority of dental implants are made out of commercially pure titanium, which is available in 4 grades depending upon the amount of carbon and iron contained. More recently grade 5 titanium has increased in use. Grade 5 titanium, Titanium 6AL-4V, (signifying the Titanium alloy containing 6% Aluminium and 4% Vanadium alloy) is believed to offer similar osseointegration levels as commercially pure titanium. Ti- 6Al-4V alloy offers better tensile strength and fracture resistance. Implant surfaces may be modified by plasma spraying, anodizing, etching, or sandblasting to increase the surface area and osseointegration potential of the implant.

example of cone beam CT scan use for implant surgery

<Previous     ^Top     Next>

Training:

There is no specialty recognized by the ADA for dental implants in the United States. Implant surgery may be performed as an outpatient under general anesthesia, oral conscious sedation, nitrous oxide sedation, intravenous sedation or under local anesthesia by trained and certified clinicians including general dentists, endodontists, oral surgeons, periodontists, and prosthodontists.

<Previous     ^Top     Next>

Surgical Procedure:

 

Surgical planning

Prior to implant surgery, careful and detailed planning is required to identify vital structures such as the inferior alveolar nerve or the sinus, as well as the shape and dimensions of the bone to properly orient the implants for the most predictable outcome. Two-dimensional radiographs, such as panoramic or periapicals are often taken prior to the surgery. in certian cases, a Cone-Beam-CT (CBCT) may be used.  This scan will be used in a specialized 3D modeling programs to further assess the implant site..

 

During the surgery, a 'stent' may sometimes be used to facilitate the placement of implants. A surgical stent is an acrylic wafer that with pre-drilled holes to show the position and angle of the implants to be placed. The surgical stent may be produced using stereolithography following computerized planning of a case from the CBCT scan. Due to the complexity of this approach, CBCT guided surgery may double the cost compared to those more commonly accepted approaches.

 

Basic procedure

In its most basic form, the placement of an implant requires a preparation into the bone using either hand osteotomes or precision drills with highly regulated speed to prevent overheating or pressure necrosis of the bone. Once implant is placed, a period of time will be lapsed to allow the bone to grow on to the surface of the implant. This healing process is called osseointegration. When an implant is integrated, a crown or crowns will be placed on the implant.

Unlike conventional dental implants, certain implants, especially a class of Mini dental implants may be loaded immediately and still have a high survival rate (94%). The amount of time required to place an implant will vary depending on the experience of the practitioner, the quality and quantity of the bone and the difficulty of the individual situation.

 

Surgical procedure

At the planned implant sites, a pilot hole is bored into the recipient bone, taking care to avoid the vital structures (in particular the inferior alveolar nerve or IAN and the mental foramen within the mandible). A guide pin is placed to visualize positioning, angulation and depth prior to implant placement. Traditionally, an incision is made over the crest of the site where the implant is to be placed. This is referred to as a 'flap'. Some systems allow for 'flapless' surgery where a piece of mucosa is punched-out from over the implant site. Proponents of 'flapless' surgery believe that it decreases recovery time while its detractors believe it increases complication rates because the edge of bone cannot be visualized. Because of these visualization problems flapless surgery is often carried out using a surgical guide constructed following computerized 3D planning of a pre-operative CT scan.

Regardless of type of flap, once the pathway is confirmed, drilling will begin. Drilling into jawbone usually occurs in several separate steps. The pilot hole is expanded by using progressively wider drills (typically between three and seven successive drilling steps, depending on implant width and length). Care is taken not to damage the osteoblast or bone cells by overheating. A cooling saline or water spray keeps the temperature of the bone to below 47 degrees Celsius (approximately 117 degrees Fahrenheit). Modern implant screw are usually self-tapping, and is screwed into place at a precise torque so as not to overload the surrounding bone (overloaded bone can die, a condition called osteonecrosis, which may lead to failure of the implant to fully integrate or bond with the jawbone). Typically in most implant systems, the osteotomy or drilled hole is about 1mm deeper than the implant being placed, due to the shape of the drill tip. Surgeons must take the added length into consideration when drilling in the vicinity of vital structures.

 

Healing time

The amount of time required for an implant to become osseointegrated is a hotly debated topic. Consequently the amount of time that practitioners allow the implant to heal before placing a restoration on it varies widely. In general, practitioners allow 2–6 months for healing but preliminary studies show that early loading of implant may not increase early or long term complications. Minimally invasive methods of early dental implant placement reduce the cost of installed implants and shortens the implant-prosthetic rehabilitation time with 4–6 months. If the implant is loaded too soon, it is possible that the implant may move which results in failure. For conventional implants, the subsequent time to heal, possibly graft, and eventually place a new implant may take up to eighteen months. For this reason many are reluctant to push the envelope for healing.

 

One-stage, two-stage surgery

When an implant is placed either a 'healing abutment', which comes through the mucosa, is placed or a 'cover screw' which is flush with the surface of the dental implant is placed. When a cover screw is placed the mucosa covers the implant while it integrates then a second surgery is completed to place the healing abutment.

 

Two-stage surgery is sometimes chosen when a concurrent bone graft is placed or surgery on the mucosa may be required for esthetic reasons. The latter is usually important where an implant is placed in the "esthetic zone". This allows more control over the healing and as a result the predictability of the final result. Some implants are one piece so that no healing abutment is required.

 

In carefully selected cases, patients can be implanted and restored in a single surgery, in a procedure labeled "Immediate Loading". In such cases a provisional prosthetic tooth or crown is shaped to avoid the force of the bite transferring to the implant while it integrates with the bone.

 

Surgical timing

There are different approaches to place dental implants after tooth extraction. The approaches are:

 1.Immediate post-extraction implant placement.

 2.Delayed immediate post-extraction implant placement (2 weeks to 3 months after extraction).

 3.Late implantation (3 months or more after tooth extraction).

 

As to the timing of loading of dental implants, the procedure of loading could be classified into:

 1.Immediate loading procedure.

 2.Early loading (1 week to 12 weeks).

 3.Delayed loading (over 3 months)

 

Immediate placement

An increasingly common strategy to preserve bone and reduce treatment times includes the placement of a dental implant into a recent extraction site. In addition, immediate loading is becoming common as the rate of success is becoming more acceptable. This can cut months off the treatment time and in some cases a prosthetic tooth can be attached to the implants at the same time as the surgery to place the dental implants. Most data suggests that when placed into single rooted tooth sites with healthy bone and mucosa around them, the success rates are comparable to that of delayed procedures with no additional complications. Since one out of three implants requires a minimum addition of bone tissue, surgical techniques for underlying bone augmentation are currently under a large scale development.

 

Teeth in a Day

"Teeth in a day", "All-on-four"], "Fast and fixed" are similar surgical concepts whereby implants are placed on the same day and a fixed prosthesis is attached to them. This allows the patient to leave with a fixed solution as opposed having to make do with a removal temporary prosthesis whilst the implant osseointegrate with the bone. This concept is appropriate for completely edentulous jaws where either the teeth are to be extracted or have already been removed.

 

Use of CBCT scanning

Cone Beam CT (3D Dental X-ray imaging) is used preoperatively to accurately pinpoint vital structures including the inferior alveolar canal, the mental foramen, and the maxillary sinus, the chances of complications might be reduced as is chairtime and number of visits. Cone beam CT scanning, when compared to traditional medical CT scanning, utilizes less than 2% of the radiation, provides more accuracy in the area of interest, and is safer for the patient. CBCT allows the surgeon to create a surgical guide, which allows the surgeon to accurately angle the implant into the ideal space.

 

<Previous     ^Top     Next>

Complementary Procedures

 

Sinus Lift

Sinus lift is a common surgical intervention. A dentist or specialist with proper training will attempt to increase the thickness of the bone of the maxilla towards towards the sinus with some form of bone substance. This results in more volume for a better quality bone site for the implantation. Prudent clinicians who wish to avoid placement of implants into the sinus cavity pre-plan sinus lift surgery using the CBCT X-ray.

 

Bon Graft

Bone grafting will be necessary in cases where there is a lack of adequate maxillary or mandibular bone in terms of front to back (lip to tongue) depth or thickness; top to bottom height; and left to right width. Sufficient bone is needed in three dimensions to securely integrate with the root-like implant. Improved bone height—which is very difficult to achieve—is particularly important to assure ample anchorage of the implant's root-like shape because it has to support the mechanical stress of chewing, just like a natural tooth.

 

A wide range of grafting materials and substances may be used during the process of bone grafting / bone replacement. They include the patient's own bone (autograft), which may be harvested from the hip (iliac crest) or other spare site. This requires a separate surgical site, and most likely hospital time.  Most commonly is the use of processed bone from human cadavers (allograft). This bone is demineralised to prevent tissue rejection. Other products available are Bovine bone (xenograft); artificially produced bone-like substances (calcium sulfate with names like Regeneform; and hydroxyapatite or HA, which is the primary form of calcium found in bone) or calcium phosphosilicate which is available in a mouldable putty form. The HA is effective as a substrate for osteoblasts to grow on. Some implants are coated with HA for this reason, although the bone forming properties of many of these substances is a hotly debated topic in bone research groups. Alternatively the bone intended to support the implant can be split and widened with the implant placed between the two halves like a sandwich. This is referred to as a 'ridge split' procedure.

 

Correctly performed, a bone graft produces live vascular bone which is very much like natural jawbone and is therefore suitable as a foundation for implants.

<Previous     ^Top     Next>

Considerations

 

For dental implant procedure to work, there must be enough bone in the jaw, and the bone has to be strong enough to hold and support the implant. If there is not enough bone, more may need to be added with a bone graft procedure discussed earlier. Sometimes, this procedure is called bone augmentation, or guided bone regeneration. Mini dental implants are particularly useful in the endentulous arch with minimal remaining bone facio-lingually. In addition, natural teeth and supporting tissues near where the implant will be placed must be in good health.

 

In all cases careful consideration must be given to the final functional aspects of the restoration, such as assessing the forces which will be placed on the implant. Implant loading from chewing and parafunction (abnormal grinding or clenching habits) can exceed the biomechanic tolerance of the implant bone interface and/or the titanium material itself, causing failure. This can be failure of the implant itself (fracture) or bone loss, a "melting" or resorption of the surrounding bone.

 

Your dentist must first determine what type of prosthesis will be fabricated. Only then can the specific implant requirements including number, length, diameter, and thread pattern be determined. In other words, the case must be reverse engineered by the restoring dentist prior to the surgery. If bone volume or density is inadequate, a bone graft procedure must be considered first. The restoring dentist may consult with the oral surgeon, periodontist, endodontist, or another trained general dentist to co-treat the patient. Usually, physical models or impressions of the patient's jawbones and teeth are made by the restorative dentist at the implant surgeons request, and are used as physical aids to treatment planning. If not supplied, the implant surgeon makes his own or relies upon advanced computer-assisted tomography or a cone beam CBCT scan to achieve the proper treatment plan.

 

Computer simulation software based on CBCT scan data allows virtual implant surgical placement based on a barium impregnated prototype of the final prosthesis. This predicts vital anatomy, bone quality, implant characteristics, the need for bone grafting, and maximizing the implant bone surface area for the treatment case creating a high level of predictability. Computer CAD/CAM milled or stereolithography based drill guides can be developed for the implant surgeon to facilitate proper implant placement based on the final prosthesis' occlusion and aesthetics.

 

Treatment planning software can also be used to demonstrate "try-ins" to the patient on a computer screen. When options have been fully discussed between patient and surgeon, the same software can be used to produce precision drill guides. Specialized software applications such as 'SimPlant' (simulated implant) or 'NobelGuide' use the digital data from a patient's CBCT to build a treatment plan. A data set is then produced and sent to a lab for production of a precision in-mouth drilling guide.

 

<Previous     ^Top     Next>

<Previous     ^Top     Next>

implant 3D simulation with implant planning software
How is dental implant compare with natural tooth
Implant retained clip on denture
all on 4 implants

Success Rates

 

Dental implant success is related to operator skill, quality and quantity of the bone available at the site, and the patient's oral hygiene. The consensus is that implants carry a success rate of around 75%.

 

One of the most important factors that determine implant success is the achievement and maintenance of implant stability. The stability is presented as an ISQ (Implant Stability Quotient) value. Other contributing factors to the success of dental implant placement, as with most surgical procedures, include the patient's overall general health and compliance with post-surgical care.

 

Failure

 

Failure of a dental implant is often related to the failure of the implant to osseointegrate correctly with the bone, or vice-versa. A dental implant is considered to be a failure if it is lost, mobile or shows peri-implant (around the implant) bone loss of greater than 1.0 mm in the first year and greater than 0.2 mm a year after.

 

Dental implants are not susceptible to dental caries but they can develop a condition called peri-implantitis. This is an inflammatory condition of the mucosa and/or bone around the implant which may result in bone loss and eventual loss of the implant. The condition is usually, but not always, associated with a chronic infection. Peri-implantitis is more likely to occur in heavy smokers, patients with diabetes, patients with poor oral hygiene and cases where the mucosa around the implant is thin.

 

Currently there is no universal agreement on the best treatment for peri-implantitis. The condition and its causes is still poorly understood.

 

Risk of failure is increased in smokers. For this reason implants are frequently placed only after a patient has stopped smoking as the treatment is very expensive. Rarely, an implant may fail because of poor positioning at the time of surgery, or may be overloaded initially causing failure to integrate. If smoking and positioning problems exist prior to implant surgery, clinicians often advise patients that a bridge or partial denture rather than an implant may be a better solution.

 

Failure may also occur independently of the causes outlined above. Implants like any other object suffers from wear and tear. If the implant(s)in question are replacing commonly used teeth, then these may suffer from wear and tear and after years may crack and break up, although this is a very rare occurrence. The only way to minimize the risk of this happening is to visit your local dentist for regular reviews.

 

In the majority of cases where an implant fails to integrate with the bone and is rejected by the body the cause is unknown. This may occur in around 5% of cases. To this day we still do not know why bone will integrate with titanium dental implants and why it does not reject the material as a 'foreign body'. Many theories have been postulated over the last five decades. A recent theory argues that rather than being an active biological tissue response, the integration of bone with an implant is the lack of a negative tissue response. In other words, for unknown reasons the usual response of the body to reject foreign objects implanted into it does not function correctly with titanium implants. It has further been postulated that an implant rejection occurs in patients whose bone tissues actually react as they naturally should with the 'foreign body' and reject the implant in the same manner that would occur with most other implanted materials.

 

<Previous     ^Top     Next>

Contraindications

 

There are few absolute contraindications to implant dentistry. However, there are some systemic, behavioral, and anatomic considerations that should be assessed.

<Previous     ^Top

before and after implant restoration in correcting a missing tootn

Before and After Photos

©2002 - 2017 A Beautiful Smile Dentistry, LLC. All rights reserved.