Selective Grinding In Prosthodontics

Selective Grinding.
In anatomic tooth forms to attain balanced occlusion, bilateral tooth contacts of the posterior teeth are required to evenly distribute the forces.

• A cusp fossae marginal ridge relation of maximum intercuspation, when the jaws are in a terminal hinge position, is needed to attain balance. There should be no occlusal interference when jaw movements occur to and from centric and eccentric positions.
• If selective grinding is done maximum intercuspation is when the jaws are in centric relation, and balanced centric occlusion is achieved.
• If selective grinding is done to make simultaneous cusp tip-to-cusp tip contact on both sides of the arch when the jaws are in a right or left lateral position, balanced occlusion in a static eccentric position exists.

Read And Learn More: Complete Dentures Question and Answers

• When the anterior teeth make an incisal edge to incisal edge contact in a straight protruded relation and if the posterior teeth are altered to make cusp contacts at the same time balanced occlusion in protrusion exists
• The buccal cusps of the mandibular posterior teeth and the lingual cusps of the maxillary posterior teeth maintain the vertical dimension of jaw separation by contact in the fossae and on the marginal ridges of their antagonists. Generally, the functional cusp of the upper (lingual cusp) and functional cusp of the lower (buccal cusp ) are never ground.
• The non-functional cusps, deepening of fossae, and the cuspal inclines are the ones that are altered to achieve balance.

Relining and Rebasing.

Relining and rebasing Definition

• Relining is the process of adding some material to the tissue side of a denture to fill the space between the tissue and the denture base. Rebasing is the process of replacing all the base materials of a denture.
• The purpose of such a process is to fill the space between the tissue and the denture base without changing the position of the teeth and the relation of the dentures.

Relining and rebasing Indications for relining and rebasing

1. Immediate dentures after three to six months when the extraction sockets have healed and remodeled.
2. Extensive ridge resorption with loose fitting denture especially when the patient is happy with the esthetic aspect.
3. Poor patients who cannot afford the cost of having new dentures constructed.
4. Geriatric or chronically ill patients.

Relining and rebasing For A Denture To Be Relined Or Rebased

1. Healthy oral tissue.
2. Correct occlusal vertical dimension.
3. Centric occlusion should coincide with centric relation.
4. Adequate interocclusal distance.
5. Satisfactory esthetics (The size, shapes, shade, and arrangement of the artificial teeth must be satisfactory).
6. Coverage of denture bases should be adequate.
7. The denture base extensions should be adequate to distribute masticatory forces to a large area as possible.
8. Satisfactory speech.

Relining and rebasing Contraindications

1. When centric relation record is not accurate.
2. When interocclusal distance is not proper.
3. Excessive bone resorption.
4. When abused soft tissues are present.
5. When the patient complains of temporomandibular joint problems.
6. When the denture base is under extended.
7. Poor esthetics.
8. Major speech problem.
9. In severe osseous undercuts.

Relining and rebasing Relining Techniques

There are two major relining techniques:

• Open-mouth technique
• Closed-mouth technique

In an open-mouth technique, major emphasis is given to making separate impressions, with independent attention given to recording jaw relations. In a closed-mouth relining technique a habitual centric occlusion is usually accepted. This centric occlusion may or may not be the same as centric relation.

Relining and rebasing Tissue Preparation

1. Excessive hypertrophic tissue should be surgically removed. The dentures can be used as a surgical splint.
2. The oral mucosa should be free of areas of irritation.
3. Removal of the dentures from the mouth during sleep is a must for several weeks before treatment commences.
4. The dentures should be left out of the mouth for at least two to three days before making the final impression.
5. Daily massage of the soft tissues is helpful to stimulate their blood supply.

Relining and rebasing Denture preparation

1. Pressure areas on the tissue surface of the dentures should be relieved.
2. Minor occlusal disharmony is corrected by selective grinding.
3. Small border inadequacies are corrected.
4. A correct posterior palatal seal area should be established before the final impression. Stick
   compound and auto-polymerizing acrylic resin can be used for this purpose.

Relining and rebasing Principal pitfalls

The principal pitfalls that must be avoided in any technique to refit a complete denture are as follows:

1. Do not increase the occlusal vertical dimension.
2. Multiple even contacts (maximum intercuspation) should be present in centric relation.
3. Do not permit the maxillary denture to move forward during impression-making.
4. Ensure that centric relation and centric occlusion are identical.
5. Ensure that an accurate posterior palatal seal has been established.
6. An equal thickness of the final impression material should be used.

Relining and rebasing Chairside Technique

• Both the static technique and the functional impression technique are good techniques in cases for simple situations and complicated situations such as excessive tissue changes.
• The chairside technique was uncommon due to chemical burn on the mucosa; a bad odor; lack of color stability of the lined acrylic and if the denture was not positioned correctly, the material was difficult to remove.
• The use of a visible light-cured (VLC) resin system as a substitute for the liner was a better choice of material than acrylic because of its many advantages.
• Advantages are a good fit, strength, ability to polymerize without residual components, ease of fabrication and manipulation, patient acceptance, ability to bond with other denture base resins and low bacterial adherence.

Selective Grinding Procedures.

The implacability of the basal seat mucosa (relief) must be considered when the teeth are altered by selective grinding procedures.

Selective grinding procedures are done to correct the occlusal discrepancies which have taken place after the denture is waxed up and processed.

Selective grinding of anatomic teeth is done to achieve:

1. Balanced occlusion when the jaws are in centric relation.
2. Balanced occlusion in eccentric relations.
3. On the working side: By having all of the posterior teeth and the cuspids in contact.
4. On the balancing side: Only the posterior teeth should contact.
5. Protrusive balance: The anterior teeth should make incisal edge-to-edge contact with the tips of the buccal and lingual cusps of the posterior teeth in contact.

Selective grinding procedures Procedure

Selective grinding procedures Locating the Area of Premature Contact

1. The horizontal and lateral condylar inclinations are set with the protrusive interocclusal relation record.
2. The horizontal condylar elements are released to allow freedom of the articulator in eccentric
   positions.
3. The incisal guide pin is raised and secured above the height of the guide table.
4. Areas of tooth contact in the centric and eccentric positions are evaluated.
5. The articulator is closed with the condylar elements against the centric relation and stops until the posterior teeth are in contact and the anterior teeth are out of contact.
6. If the rest of the tooth is out of occlusion when the lingual cusps of the maxillary posterior teeth
   and the buccal cusps of the mandibular posterior teeth occlude then premature contact exists.

Selective grinding procedures Recording the Premature Contact

After securing the right condylar element in the centric position place the lingual cusps of the maxillary posterior teeth in balancing relation with the buccal cusps of the mandibular posterior teeth.

Selective grinding procedures Possible Prematurities

1. If the balancing side is not in the correct relation, the error appears on either balancing or
   working side.
2. If the balancing contact is excessive, the working side teeth will be out of contact.
3. If the working side contact is excessive, the balancing side will not contact.
4. If the teeth on the working side are too long, there will be no contact on the balancing side.
5. If a single tooth is high on the working side, there will be no contact between the balancing and the working side.

Repeat the procedure with the left side as the working side and record all the premature contacts on both sides with articulating tape. Place the tape on the occlusal surfaces and the incisal edges of all the mandibular teeth.

Selective grinding procedures Steps in selective grinding procedures

Return the incisal guide pin to the table and:

1. If the cusp is high in centric and eccentric position, reduce the cusp.
2. If the cusp is high in centric and not in the eccentric position, deepen the fossae or the marginal ridges.

Selective grinding procedures For Balanced Grinding Occlusion

Working side reduces the inner inclines of:

1. The buccal cusps of the maxillary teeth and
2. The lingual cusps of the mandibular teeth.

The balancing side reduces the inner inclines of the mandibular buccal cusps. Protrusive balance reduces the distal inclines of the maxillary cusps and the mesial inclines of the mandibular cusps.

Selective grinding procedures Refining

After the occlusal corrections are done refine the occlusal anatomy using the mounted inverted cone points and polish all the ground surfaces with pumice on a wet rag wheel.

Selective grinding procedures Selective Grinding Of Non-Anatomic Teeth

1. The steps of recording and marking the occlusal discrepancies are the same.
2. A mounted wheel is used to grind the occlusal surfaces of the teeth until simultaneous even
   contacting areas on the right and left are developed without anterior tooth contact.
3. The altered surfaces are polished with wet pumice on a wet rag wheel.

Stripping method for the occlusal equilibration of zero degree teeth: by Dr. Gronas in 1970

This is a carborundum stripping technique to eliminate cuspal interferences. A 220-grit paper is used to modify porcelain teeth and a fine 320-grit paper is used for acrylic resin teeth.

Selective grinding procedures Procedure

Selective grinding procedures Adjusting for Centric Occlusion

1. Locate the premature contacts as in selective grinding procedures and reduce gross interferences with a stone or bur until a flat occlusal plane is obtained in centric and eccentric positions.
2. After the gross reduction is done if any, a carborundum strip of the appropriate width with the abrasive side against the teeth is placed, and the articulator is closed in centric relation.
3. With light pressure on the upper member of the articulator, the strip is pulled briskly between the teeth without altering the vertical dimension of occlusion.
4. Reduction of the contacts with the strips is continued by stripping an equal number of times with the abrasive side alternated up and down until uniform bilateral contacts on the posterior teeth are obtained.
5. This procedure is repeated in the eccentric position.
6. Finish the reduction with finer grits of sandpaper strips to produce a smooth flat surface.

Impression Trays.

Defined as a device that is used to carry, confine, and control the impression material for making an impression.

Impression trays Types

1. Stock trays
   1. Edentulous trays
      1. Perforated
      2. Non-perforated
2. Dentulous
   1. Perforated
   2. Non-perforated
   3. Rimlocked
3. Custom trays or Special trays
   • To make corrective or final wash impressions.

Impression trays Materials used

• Shellac
• Tray compound
• Acrylic resin (with spacer and stops)
• Metallic (Chrome-Cobalt).

Impression Trays Functions Of Impression Trays

1. To support the impression material while in contact with oral tissues.
2. For various impression techniques such as the Selective pressure technique.
3. To support the impression material so that cast can be poured.

Impression trays For Successful Impression Knowledge Of The Following Is Necessary

1. Oral anatomy
2. Impression materials
3. Impression technique
4. Operator skill.

Impression trays Custom Made Tray

Impression trays Ideal Requirements

1. The material should be rigid and dimensionally stable.
2. Accurately and closely adapting to oral tissues.
3. Impression material should adhere to the tray.
4. There should be sufficient space between the vestibular sulcus and the tray border.
5. Should be strong enough to carry impression material.

Repair

It is the procedure by which the fractured parts are assembled and joined using the same denture base material.

Repair Types Of Fractures

• Tooth fracture
• Denture fracture.

Repair Tooth Fracture

Can be an anterior tooth or a posterior tooth. The tooth material as plastic tooth or porcelain tooth can be replaced.

Repair Anterior Tooth Replacement

1. Keeping the labiogingival margin intact the fractured tooth is removed using round bur.
2. If it is a porcelain tooth, heat it with a torch and remove it with a No. 7 wax spatula in the ridge lap area.
3. Another tooth of appropriate shade and size is selected and positioned in place with sticky wax.
4. A plaster index is made on the labial surface of the tooth to be restored including the adjacent tooth.
5. After the plaster index sets, its removed and indentations are placed in the replacement area.
6. Resin is added to the lingual aspect of the tooth and this tooth is fixed in place with the help of an index.
7. Place in a pressure pot for 30 minutes at 20 psi pressure and cure.
8. Remove and polish with pumice and wet rag wheel.

Repair Posterior Tooth Replacement

1. The casts have to be mounted in centric relation and after checking the occlusion the tooth to be replaced has to be sealed to the opposite tooth in occlusion with sticky wax.
2. The area from which the tooth was removed has to be intended with a round bur.
3. Close the articulator, check the occlusion, and fill the space with resin between the cervical aspect of the tooth and denture after applying monomer to the tooth.
4. After the final cure, polish the denture and check the occlusion.
5. If required a face-bow record and transfer are made.
6. Right, left lateral records and a straight protrusive record can be made before mounting the casts.
7. The records are then used to mount casts on the articulator and adjust the condylar inclinations and Bennett shift.

Repair Denture Fracture

Repair Types

1. Non-separated fracture or Midline fracture
2. Complex fracture (Fractured into two or more parts)
3. Fractured dentures with missing section.

Repair Procedure For Repair

1. Denture is held together with sticky wax and small wooden sticks.
2. A cast of model plaster is poured after undercuts inside the denture are blocked out.
3. The denture is removed from the cast, free of sticky wax, and 2–3 mm of acrylic from the midline fracture area is removed.
4. A long rounded bevel is made on each side of the opening about 5 mm wide along the entire midline and onto the labial surface.
5. The plaster cast is painted with a separating solution and the two pieces of the denture are placed back on the cast.
6. The repair acrylic is applied by wetting the pieces to be repaired with monomer and dusting
   on the polymer and adding more monomer until the fracture area is covered.
7. Curing of acrylic: Placed in a pressure pot at 30 pounds per square inch pressure for about 30 minutes.
8. The denture is then removed from the pressure pot, trimmed, and polished. The steps for repair of the mandibular denture are the same as those for the maxillary denture.

Repair Cast Strengthener For Repeated Mandibular Denture Fractures

• A cobalt-chromium cast strengthener is used along with heat-cure acrylic resin.
• Strengthener is placed on the cast before wax-up.
• After waxing up the strengthener is embedded in a waxed-up denture.
• This waxed-up denture is processed in the usual manner.
• During the boil-out of the wax, the strengthener is cleaned and placed back on the cast in position, and the denture is packed.

Repair Light-cured resin repairs

• The resin is cured with a visible light source that emits intense light in the 400–500 nm range.
• The pieces of the broken denture are assembled and stabilized with sticky wax.
• A cast is made and it is coated with a separating agent.
• The borders of the fractured sections are prepared.
• The edges are coated with monomer and the light-cured resin is adapted to the fracture area.
• Light from the visible light source (or a hand-held unit) is applied to the repair area for five to ten minutes.
• Minimal finishing and polishing are required.

Repair Advantages

1. Convenient to use.
2. Neat to work and no free monomer.
3. Less time is needed to complete the repair.
4. Easy control of the position of the repair material.

Differences between natural and artificial occlusion.

Complete Denture Occlusion

Supported by Soft and hard tissues.

Complete Denture Occlusion Soft Tissues

• They vary in thickness, resiliency, and tolerance to pressure and are in a state of constant change. They respond rapidly to external stimuli such as pressure, scuffing, heat, and cold and to internal
• stimuli such as the amount of contained fluids, nutrients, salts, and blood pressure. These changes in soft tissues affect the position of the bases and the occlusion they carry.

Hard tissues

Hard tissues The reaction of Bone to Pressure and Tension

• If the force on a tooth is principally in line with its long axis, there is an apposition of bone.
• Lateral forces tangential to the long axis of a tooth cause bone resorption, tooth migration, and mobility.
• In natural teeth, these lateral forces are countered by avascular tissues such as teeth, joints, and discs that are covered and protected by specialized fibrous tissue, fibrocartilage, or hyaline cartilage.
• In natural dentition when stress is applied to bone it stimulates the osteoblasts and the osteoclasts to remodel bone.
• In complete denture occlusion: The stresses of pressure and tension on bone are transmitted through the residual ridge. If pressure is against the periosteum, the blood supply is disturbed and leads to bone resorption.
• Blood supply is from two sources: from the periosteum and from its internal system of arteries.
• Arteries from the external periosteal network enter the bone; interference as direct pressure or inflammation by a denture base lead to bone necrosis and resorption.

Hard tissues Differences Between Natural And Artificial Occlusion

Occlusion of natural and artificial teeth varies to a great extent. It is important for one to know about these differences in order to understand the need for balanced occlusion in a complete denture which is discussed later.

Hard tissues Natural Teeth

1. Natural teeth are retained by periodontal tissues with proprioceptive feedback.
2. Natural teeth function independently and can withstand occlusal forces by proper dissipation of these forces.
3. Malocclusion in natural teeth is well adjusted to and is normal without deteriorating effects.
4. Non-vertical forces are well tolerated and only affect the teeth involved
5. Incising does not affect the posterior teeth.
6. The second molar region is the ideal area for heavy mastication for better leverage and power.
7. Bilateral balance is not found in natural dentition.
8. Proprioceptive impulses help to avoid occlusal interference and establish a stable habitual occlusion away from centric relation.

Hard tissues Artificial Teeth

1. Artificial teeth are placed on bases seated on resilient tissues.
2. The artificial teeth move as a unit.
3. Artificial teeth function as a unit on their base with the distribution of forces on the entire denture
   base coverage area.
4. Malocclusions pose an immediate response involving the entire tissue support.
5. Non-vertical forces damage the supporting tissues.
6. Incising will displace the denture from its basal seat.
7. Placing load only on the second molar region can shift the denture base.
8. Bilateral balance is important to produce stability and retention of the denture.
9. As there is no feedback and as the denture relation is centric relation. Any occlusal interferences in this position can displace the denture.

Theories of Occlusion

Occlusion: It is the static contact of teeth that exists after the jaw movements have stopped. It is the contact relationship between the upper and lower teeth.

All occlusal forms should at least have a tripod contact in centric relation. Balanced occlusion should have tripod contact even in eccentric relations.

Theories of Occlusion Concepts Of Occlusion/Theories Of Occlusion

1. Spherical concept of occlusion (Monson)
2. Bonwill’s theory of occlusion
3. Conical theory of occlusion
4. Organic concept of occlusion
5. Neutrocentric concept of occlusion
6. Centric occlusion
7. Balanced occlusion.

Theories of occlusion Spherical concept of occlusion (Monson in 1918)

• It is defined as the lower teeth moving over the surface of the upper teeth over the surface of
  a sphere with a diameter of 8 inches (20 cm).
• The center of the sphere being the center of the glabella and the surface of the sphere passes through the glenoid fossa. This theory was based on the findings of Von Spee.
• Instruments based on this theory were the Maxillomandibular instrument and the Hageman balancer. Based on this concept, the anteroposterior and mesiodistal inclines of the artificial teeth should be arranged in harmony with a spherical surface.

Theories of occlusion Bonwill’s theory of occlusion/theory of equilateral triangle (Wga Bonwill)

• Bonwill’s theory of occlusion proposed that the teeth move in relation to each other as guided by the condylar controls and the incisal point. In this theory, there is a 4-inch distance between the condyles and between the condyles and incisor point. The instrument based on this theory is the mean value articulator.
• It permits lateral movements but as the condylar guidances are not adjustable they move in a horizontal plane.

Theories of Occlusion Conical Theory Of Occlusion

• The conical theory of occlusion proposed that the lower teeth move over the surfaces of upper teeth over the surface of a cone generating an angle of 45° with the central axis of the cone tipped 45° to the occlusal plane.
• Instrument based on this theory – Hall automatic articulator by RE Hall. This requires 45° cusp teeth to conform to this concept of occlusion.

Theories of Occlusion Organic Concept Of Occlusion

• The aim of the Organic Concept of Occlusion is to relate the occlusal surfaces of teeth to be in harmony with the muscles and joints during function.
• Organic occlusion employs cusp form posterior teeth that are not arranged in protrusive and bilateral balance.
• The shapes of the teeth are altered to have cusps suitable for the patient.
• The movement of the condyle determines the direction of the ridges and grooves of the teeth.
• Mandibular movements determine the cusp height, fossa, depth of the fissure, and concavity of the lingual surfaces. The muscles and joints determine the mandibular position of occlusion without tooth guidance.

Theories of occlusion Three phases of organic occlusion are:

1. The posterior teeth should protect the anterior teeth in the centric occlusal position.
2. Maxillary incisors should have vertical overlap sufficient to provide separation of the posterior
   tooth during incisal edge-to-edge contact.
3. In excessive lateral mandibular movements, the cuspids should prevent contact of all other teeth.

Theories of Occlusion Neutrocentric Concept Of Occlusion

• The term was neutrocentric denotes an occlusion that eliminates the anteroposterior and buccolingual inclines in order to direct the forces to the posterior teeth.
• In this concept, the plane of occlusion should be flat and parallel to the residual alveolar ridge and not dictated by the horizontal condylar guidance. This is similar to the monoplane occlusion used to set non-anatomic teeth.
• The eurocentric concept of occlusion maintains that the anteroposterior plane of occlusion should be parallel with the plane of the denture foundation and not inclined to form compensating curves.
• In a mediolateral direction, the teeth are set flat with no medial or lateral inclination. The horizontal condylar guidance and the lateral condylar guidance of the articulator are set at zero as the teeth are not arranged for balancing contacts.
• The condylar elements of the articulator may be secured to function in the opening and closing movements. To direct force toward the center of the support.
• The buccolingual width of the teeth is reduced and the number of teeth is reduced to direct
  the forces in the molar and bicuspid area of support.

Theories of occlusion Balanced occlusion

• Balanced occlusion is the simultaneous contacting of the maxillary and mandibular teeth on the
  right and left and in the anterior and posterior occlusal areas when the jaws are in either centric
  or eccentric relation.
• Balanced occlusion is associated with cusp form posterior teeth. Teeth arranged in balanced occlusion provide stabilizing forces to the denture bases on their basal seat when the teeth make contact and the jaws are in centric or eccentric relation.

Theories of occlusion Centric Occlusion

• It is the maximum intercuspation between the maxillary and mandibular teeth. Either centric occlusion can be made to coincide with centric relation or a range of tooth contact in this area called freedom in centric can be given.
• In centric occlusion, only the working occlusal units are in contact. The first bicuspids, the cuspids, and the incisors have at least 1-millimeter clearance when the teeth are in centric occlusion.
• In the mediolateral direction, the buccal surfaces of the posterior teeth that extend over the lateral half of the residual alveolar ridge are ground to have at least 1-millimeter clearance with their antagonists.

Requirements of Complete Denture Occlusion

• Stability of occlusion at centric relation position.
• Balanced bilateral occlusal contacts for all eccentric mandibular movements.
• Unlocking the cusps mesiodistally allows the settling of the bases due to tissue deformation and bone resorption.
• Control of horizontal force by buccolingual cusp height reduction.
• Anterior incisal clearance during all posterior masticatory functions.
• Minimum occlusal contact areas for reduced pressure.
• Generous sluice-ways (Anatomic tooth forms).

Complete denture occlusion The requirements of complete denture occlusion are divided into three units:

1. Incising,
2. Working,
3. Balancing.

Complete denture occlusion Requirements For Incising Units

1. Sharp enough to cut efficiently.
2. During mastication, incising units should be out of contact.
3. Contact only in protrusive incising function.
4. Horizontal overlap to allow for base settling without interference.
5. Should have flat incisal guidance as possible as esthetics and phonetics permit.

Complete denture occlusion Requirements For Working Occlusal Units

1. Efficient in cutting and grinding.
2. Decreased buccal-lingual width to minimize the workforce to the denture foundation.
3. The plane of occlusion is as parallel as possible to the mean foundation plane.
4. Placed over the ridge crest in the masticating area for lever balance.
5. Should have a surface to receive and transmit the force of occlusion vertically.
6. Should center the workload near the anteroposterior center of the denture.
7. Should function as a group with simultaneous harmonious contacts.

Complete denture occlusion Requirements For Balancing Occlusal Units

1. Should contact on the second molars when the incising units contact in function.
2. Should contact at the end of the chewing cycle when the working units contacts.
3. Should have smooth gliding contacts for lateral and protrusive excursions.

Sears Axioms For Artificial Occlusion

These axioms were published by Sears in 1973 and have guided the planning of complete denture occlusion for many years:

1. The smaller the area of the occlusal surface acting on food, the smaller will be the crushing force on food transmitted to the supporting structures.
2. The vertical force applied to an inclined occlusal surface causes a nonvertical force on the denture base.
3. The vertical force applied to a denture base supported by yielding tissue causes the base to shift when the force is not centered on the base.
4. The vertical force applied laterally to the ridge crest creates tipping forces on the base.
5. Vertical forces applied to inclined supporting tissues will cause non-vertical forces on the
   denture base.

These axioms aid the dentist in the final outcome of success in complete denture as it helps to increase the stability, function, and comfort of the denture.

Endosteal Implants

An endosteal implant is an alloplastic material surgically inserted into the residual ridge, primarily to
serve as the prosthodontic foundation. Endo means Within and Osteal means Bone. The other types are sub-periosteal and intramucosal implants.

Endosteal Implants Commonly Available As:

• Pin, needle, screw, cylinder
• Plate or blade or Blade vent implant.

Endosteal Implants Depending on the Design it is Divided as:

1. Cylindrical-Microscopic retention, bonding to bone.
2. Screw root forms.
3. Combination root forms (both cylinder and screw design).

Endosteal Implants Classified As:

1. Immediate function or later function as loaded after a healing time.
2. Totally submerged or partially submerged.
3. Function with a direct bone interface or Functions with a peri-implant connective tissue ligament.
4. Final prostheses can be removed destructively or non-destructively.

Endosteal Implants Endosteal Implants

Three methods of placing an endosteal implant.

1. The implant can be immediately loaded with a provisional prosthesis.
2. It can be fully submerged and allowed to heal for a number of months (Branemark screws, sinus-lift blades).
3. It can be semi-submerged and allowed to heal out of function.

Endosteal Implants Blade Or Plate-Form Implants (by Linkow 1970)

Endosteal Implants Types: Latticework design and closed bottoms. These two types can be:

1. Coated with materials such as hydroxyapatite or
2. Plasma sprayed titanium.
   Their ease of insertion led to extensive use.

Endosteal Implants Three Insertion Techniques

1. A blade can be inserted and placed into immediate function with a temporary prosthesis or left out of function.
2. After the implant is allowed to heal undisturbed for several weeks, the healing head is replaced by the final abutment head.
3. The implant is inserted and fully submerged beneath the mucosa for extended healing. A covering cap is threaded into the abutment neck receptor site. A second surgical procedure is done to expose the covering cap and replace it with the final abutment head.

The S implants of Tatum are wide blades with horizontal loading platforms. They can be used in broad alveolar ridges. If the ridges are shallow, a lateral approach, rotating a portion of the wall of the sinus upward, maintaining the membrane intact, and adding autogenous or synthetic bone is done followed by implant placement.

Endosteal Implants Screw, Root, And Pin-Form Implants

Endosteal Implants Types

1. Smooth
2. Threaded: These types can either be coated or uncoated
3. Hollow submergible or nonsubmergable
4. Solid
5. Perforated.

Endosteal Implants Parts Of Screw Type

• Implant body fixture, First stage cover, Second stage per mucosal extension, Abutment, Hygiene screw, Transfer coping, Analog, Coping, and coping screw.
• Smooth tantalum pin implant of Scybalum was the earliest type of this. The most commonly used material is pure titanium.
• The concept of submerged healing prior to loading and the use of attachment mechanisms permit a wide range of stress-breaking and non-destructive removal of prostheses.