implantation. introduction to dental implant definition materials used for dental implant. types of...

Implantation

Introduction To Dental Implant

DefinitionMaterials used for dental implant.Types of dental implantOsseointegrationBiomechanics of osseointegrated implant.

Oral Implant:

A device or inert substance, biologic or alloplastic, that is surgically inserted into soft or hard tissues, to be used for functional or cosmetic purposes.

Oral Implant: A permucosal device which is biocompatible and

biofunctional and is placed within mucosa or, on or within the bone associated with the oral cavity to provide support for fixed or removable prosthetics.

Introduction

Losing tooth/teeth is not new problem It is possible to replace teeth that look &

function like natural teeth Implants is one of the means of achieving this

through osseointegration (biological adhesion of bone tissue & titanium)

Pioneered by prof. Per-Ingvar Branemark in 1952 ( Swedish orthopedics' surgeon)

Examples

Advantages & disadvantages of implant over conventional treatment

Implants do not involve preparation of the adjacent teeth, they preserve the residual bone, and excellent aesthetics can be achieved.

However, it is expensive, the patient requires surgery, time consuming, and technically complex.

Types of dental implants

1. Mucosal Insert

2. Endodontic Implant (Stabilizer)

3. Sub-periosteal implant

4. Endosteal or Endosseous implant Plate-form implant Ramus-frame implant Root-form implant

5. Transosseous implant

Root Form Implants

In this presentation we will focus on the Root Form Implants.

Since the introduction of the osseointegration concept and the titanium screw by Dr. Branemark, these implants have become the most popular implants in the world today.

Root form Implants come in a variety of shapes, sizes, and materials and are being offered by many different companies worldwide. Some clinicians regard them to be the Standard of Care in Oral Implantology.

These implants can be placed wherever a tooth or several teeth are missing, when enough bone is available to accommodate them. However, even if the bone volume is not sufficient to place Root form Implants, Bone grafting procedures within reasonable limits should be initiated, in order to benefit from these implants.

Root form implant shape:

Other variations dwell on the shape of the Root form implant. Some are screw-shaped, others are cylindrical, or even cone-shaped or any combination thereof.

Today, the most accepted material for dental implants is high

grade Titanium—either CP Titanium or an alloy thereof. The titanium alloy implants tend to be stronger than the CP titanium implants. The bone integration shows no difference to the two different types of titanium.

Some implants have an outer coating of Hydroxyapatite (HA). Other implants have their surface altered through plasma spraying, or beading process. This was developed to increase the surface area of the titanium implant and, thus, in theory, give them more stability. These surface treatments were also offered as an alternative to the HA coatings, which on some implants have shown to break loose or even dissolve after a few years.

Osseointegration

A time-dependant healing process where by clinically symptomatic rigid fixation of alloplastic materials is achieved, and maintained, in bone during functional loading. (Zarb & Albrektson,1991)

Factors affecting osseointegration

Implant biocompatibilityImplant designImplant surfaceImplant bedSurgical techniqueLoading condition

Bone QualityAccording to Lekholm and Zarb.,1985

Quality I Was composed of homogenous compact bone, usually found in the

anterior lower jaw.

Quality II Had a thick layer of cortical bone surrounding dense trabecular

bone, usually found in the posterior lower jaw.

Quality III Had a thin layer of cortical bone surrounding dense trabecular

bone, normally found in the anterior upper jaw but can also be seen in the posterior lower jaw and the posterior upper jaw.

Quality IV Had a very thin layer of cortical bone surrounding a core of low-

density trabecular bone, It is very soft bone and normally found in the posterior upper jaw. It can also be seen in the anterior upper jaw.

Surgical technique

Minimal tissue violence at surgery is essential for proper osseointegration.

Careful cooling while surgical drilling is performed at low rotatory rates.

Use of sharp drills.Use of graded series of drills. Proper drill geometry is important, as intermittent

drilling.The insertion torque should be of a moderate level

because strong insertion torques may result in stress concentrations around the implant, with subsequent bone resorption.

Loading condition

Delayed loading: A tow-stage surgical protocol One-stage surgical protocol

Immediate loading: Immediate occlusal loading (placed within 48 hours

postsurgery) Immediate non-occlusal Loading (in single-tooth or

short-span applications) Early loading (prosthetic function within two months)

Biomechanics of osseointegrated implant

In all incidences of clinical loading, occlusal forces are first introduced to the prosthesis and then reach the bone implant interface via the implant. So far, many researchers have, therefore, focused on each of these steps of force transfer to gain insight into the biomechanical effect of several factors such as

Force directions and magnitudes, Prosthesis type, Prosthesis material, Implant design, Number and distribution of supporting implants, Bone density, and The mechanical properties of the bone-implant interface.

Dental Implant Treatment Planning and Types of Dental Implants

How many teeth are missing? What is the degree of bone loss? Are the remaining teeth in a good position and do

they have a long-term prognosis? What does the patient expect for an end result? What treatment will result in the best cosmetic

outcome? What is the patient's budget?

Overall

What is the most practical and feasible implant treatment that will produce optimal chewing function and optimal cosmetic results in a timely and affordable manner?

Diagnosis and Treatment Planning

The evaluation of a patient as a suitable candidate for implants should follow the same basic format as the standard patient evaluation, although some areas require additional emphasis and attention:

Medical History. Psychological Status. Dental History.

Diagnostic phase

Problem list & treatment considerations

radiographic analysis surgical analysis esthetic analysis

The superstructure for completely edentulous patients

can be classified as follows:

Implant retained removable overdentureImplant supported removable overdentureFixed detachable prosthesis (Hybrid prosthesis)Implant supported Fixed Bridge 1) Screwed-in Fixed Bridge 2) Cemented Fixed Bridge

Treatment Plan Selection

Treatment planning and the decision-making process is a balance between the patient’s preferences, finances and clinical factors.

Understanding that cost is an initial barrier to case acceptance, a large percentage of patients may reject more expensive options that only include fixed prostheses.

Treatment Planning Determinants

1. Changes in Oral Structures in Edentulism

2. Posterior Ridge Anatomy3. Occlusal Forces4. Quality, Location and Quantity of Bone5. Implant Size6. Implant Location7. Arch configuration8. "Mapping" the Mandible9. Cantilevering

1. Changes in Oral Structures in Edentulism

With successive denture treatments, it is common for the vertical dimension of occlusion to decrease as bone resorbs. This promotes an increased tendency toward a skeletal Class III relationship.

2. Posterior Ridge Anatomy

Posteriorly, poor ridge height, inadequate attached gingiva and compromised ridge shape cause increased horizontal movement of the prosthesis. This increases the lateral forces that are brought to bear on the anterior implants, and will affect bar and prosthesis design.

3. Occlusal Forces The maximum bite force of subjects with a

mandibular denture supported by implants is 60 to 200% higher than that of subjects with a conventional denture

Edentulous patients that are predisposed to clenching and bruxing may be given the necessary "tools" to begin parafunctional habits once the implant bar is secured in place.

4. Quality, Location and Quantity of Bone

The minimum buccal-lingual thickness of osseous tissue required to successfully place an implant is 5 mm.

In order to achieve a 5.0 mm "flat" base, either the anterior ridge crest peak must be removed or a bone graft must be considered.

5. Implant Size The greater the surface area of the implant-bone system,

the less concentrated the force transmitted to the crest of bone at the implant interface. Similarly, the greater the surface area of the implant-bone system, the better the prognosis for the implant.

For each 0.25 mm increase in diameter, the surface area of a cylinder increases by more than 10 per cent;

For each 3.0 mm increase in length , the surface area of a cylinder increases by more than 10 per cent.

6. Implant Location Ideally, occlusal forces should be directed along

the long axis of the implants. Therefore ,The angle of the osseous ridge crest is a key determinant of implant angulation.

the distance between an implant and any adjacent "landmark" (natural tooth or another implant), which should be not less than 2.0 mm.

7. Arch configuration

Mandibular arch forms may be classified as tapered or square.

With tapered arch forms, the most posterior right and left

implants in a four-implant treatment are often placed well around the "turn" of the arch, creating a "U" shaped design that is well suited to cantilevering,

With a square arch, the four implants are usually placed in a relatively straight line. This "straight line" bar design is not well suited to cantilevering.

8. "Mapping" the Mandible

The anterior symphysis can be divided into five geographic sites:

A point, 6.0 mm anterior to each mental foramen, determines

the most posterior boundaries, right and left. Another possible implant location occurs at the midline. Two additional sites are chosen on each side of the midline,

spaced equidistantly between the midline and the respective distal sites.

9. Cantilevering The number of implants, their respective lengths

and locations, the quality of bone support, the posterior ridge anatomy, occlusal forces, and the opposing dentition are of greater importance in determining the appropriate cantilever than a suggested formula.

One method is to draw a line through the most anterior implant, and another through the two most posterior implants. The distance between the two lines can then be measured. A suggested maximum cantilever would be 1.5 times this distance.

Treatment Planning

When all the diagnostic information has been assembled, a variety of available treatment options must be assessed:

1. One-Implant Overdenture2. Two-Implant Overdenture3. Three-Implant Overdenture4. Four-Implant Overdenture5. Five-Implant Overdenture

Outline

Why are dentists moving to dental implants ? Successful dental implant. Indications for dental implants.

Cont … Advantages of dental implants: Preservation of tooth structure.

Preservation of bone.

Provision of additional support.

Retrievability.

Resistance to disease.

Increased confidence.

Improves aesthetics, function and speech.

Conclusions

References.

Why are dentists moving to dental implants ?

1. Address patient’s needs and requests.

2. High success rate.

3. Progressive development of new implant systems, Diagnostic procedures, and the introduction of novel surgical techniques.

Cont …

1. Advancement of technical procedures (CADCAM).

2. Many training courses are offered by universities, professional societies and implant manufacturers.

3. Profitable.

Successful implant Successful Osseointegration.

Successful implant Restoration of normal contour, aesthetic,

function and speech.

Successful implant Clinically: Immobile. No persistent pain, infections, paresthesia or

neuropathies.

Successful implant Radio-graphically : No peri-implant radiolucency. Vertical bone loss should be less than 0.2 mm

annually following the implant’s first year of service.

Indications for dental implants.1. Intolerance to removable dental prosthesis.

2. Need for long span fixed prosthesis with questionable prognosis.

3. Single tooth loss that will make it necessary to prepare sound adjacent teeth for a fixed prosthesis.

4. Unfavourable condition, location and number of abutment teeth.

Advantages of dental implants

1. Preservation of tooth structure.

Fixed bridge Implant

Cont …

Fixed partial dentures Single tooth implants

• Significant reduction in the amount of tooth structure is necessary • long term survival:87% at 10 yrs, 69% at 15 yrs

• Less expensive

• no need for preparation of adjacent teeth.• Long term survival: 96.5% at 11 yrs

• More expensive


1. Preservation of bone.

loss of teeth →

Lack of stimulation to the residual bone →

Decrease in bone density, height and width.

Bone resorption after extraction

Bone resorption in edentulous patients

Most of the bone loss occurs in the first year after extraction.

Continued bone loss for more than twenty years.

Four fold greater in mandible than in maxilla.

Cont … Upwards and medially in maxilla, downwards

and laterally in mandible.

Cont …

Teeth stimulate bone → maintain bone.

Implants stimulate bone → maintain bone.

Complete and partial dentures don’t stimulate bone →

Bone resorption, acceleration of bone resorption if ill fitting →

1. Decreases the surface area available for prosthesis support.

2. Eliminates favourable anatomy for retention.

3. Results in unfavourable denture bearing areas.

Cont … Always inform your patient of the anatomical

consequences of tooth loss.

Always inform your patient of the preventive nature of dental implants.


1. Provision of additional support.

Dentate patient can exert up to 1000 psi of bite force.

Edentulous patient ( complete denture wearers) can only exert up to 50 psi of bite force.

Transitioning a patient from complete denture to an implant supported prosthesis will result in a dramatic increase in bite force.

Cont … Tooth and mucosa borne dentures : Can’t re-establish posterior support.

Why ?


1. Retrievability : reservicing, replacement and salvaging of the restoration.


1. Resistance to disease. Implants are resistant to caries, natural teeth

are not.

Cont …

Consider extraction of teeth and place implants if :

The patient has poor manual dexterity, and hence can’t maintain good oral hygiene.

The patient has Xerostomia due to medications (root surface caries).


1. Increased confidence.

• Improved aesthetics, function and speech.

Conclusions Single tooth implant is the most predictable and

conservative method of tooth replacement.

Use of removable prosthesis will not allow patient to recover normal function, aesthetics, speech and comfort.

Implant supported prosthesis allow patient to function with confidence and enjoy better quality of life.

Amazing implants