DENTAL IMPLANTSDr. Atalla FathiB D S, M Sc, F I B M F
• Advances in diagnostic imagingAdvances in implant designAdvances in implant materialsSoft wares simplifying treatment planning and surgical proceduresAdvanced surgical techniquesChanging concepts in implant dentistryIntraoral and extraoral imaging procedures, used individually or in combination, suffer from the same inherent limitations of all planar two-dimensional (2D) projections:
magnification, distortion, superimposition, and misrepresentation of structures
• Advances in diagnostic imaging– Computed tomography CT– Cone beam Computed tomography(CBCT)– Microtomograph– Multi slice helical CT
• Advances in implant design
– Mini implants– One-piece implants
– Zygomatic implants
• Advances in Implant materials
–Ceramic (zirconium oxide )
Computed tomography (CT)
• Computed tomography (CT) is a digital and mathematicalimaging technique that creates tomographic sections.
• With latest CT scanners, images with sectional thickness of 0.25 mm can be obtained .
• This can be useful for determining the implant site in terms of bone density, and location to adjacent anatomic structures.
Cone beam CT:
• It uses a cone beam and reconstructs the image in any direction using special software
• It gives all the information of a CT but, at 1/8th the radiation dose and at a lower cost.
Canal draw for implant planning using CBCT
Treatment planning with a sectional implant image
Cross-sectional view of a case after implant placement
ADVANCES IN IMPLANT MATERIALS,
FORM, SHAPE AND SURFACE TOPOGRAPHY
• Mini implants
• One -piece implants
•Modifications in surface topography (coatings)
•Materials used for fabrication of implants.
MINI IMPLANTS• Mini dental implants (MDIs) are small diameter dental implants.• Are sometimes referred to as SDIs (small diameter implants), as well as NDIs (narrow body implants). • The diameter of mini-implants typically ranges from 1.8 mm to 2.9 mm.
MINI IMPLANT DESIGN• Various lengths.• Multiple tip, thread, body and head designs are available• Thread designs vary from thin to thick and thread spacing is also variable.• Square, rectangular, or o-ball heads are common.
MINI IMPLANT -indications There are two primary anatomical reasons why a mini-implant would be used rather than a narrow- or standard-diameter implant:these are lack of space and insufficient bone.To these, a third rationale may be added – that of reduced invasiveness.
MINI IMPLANT -indications1- Endentulous patients that have looselower dentures.• Where extensive surgery requiredfor conventional implants is contraindicated due to medical or age constraints.• Healing time is decreased.• Lower costs
2- Fixed crown and bridgeProper case selection is critical but the available literature has demonstrated success that rivals standard implants.3- Transitional stabilization
PROCEDURE
• Available in different lengths• Typically inserted directly through the overlying gums and into the bone beneath
• No need to surgically cut and raise flap
• A single minimally invasive surgery is needed for insertion of MDI implants
• Immediate loading done due to self tapping design.
ONE PIECE IMPLANTS
• Abutment and implant body in one pieceand not separate
• Material: Titanium Alloy – Ti-6Al-4V
• Diameter: 3.0mm Lengths: 12, 15 and 18mm.
• Maximum Strength - Minimum Profile.
• Minimal Surgery - Maximum Esthetics..
INDICATIONS
• The long-term treatment of missing
maxillary laterals and mandibular incisors.
• For treatment of spaces that cannot be
handled with larger two-piece implants….
• Also used for overdentures.
The Surgical Guide concept is based on the presurgical treatment planning using software for ideal implant positioning.• These successive diameter surgical osteotomy drill guides may be either bone, teeth, or mucosa-borne
• Surgical Guides have metal cylindrical tubes that correspond to the number of desired osteotomy preparations and specific drill diameters.• The diameter of the drilling tube is usually 0.2mm larger than the corresponding drill, thus making angle deviation highly unlikely.
CAD/CAM in implant dentistryUses• Used in designing of prosthesis• Used in milling /fabrication of prosthesis (framework)• For milling of abutments.Advantages:• Superior fit• Less degree of rotational freedom so more accurate implant abutment connection.
Ceramic implant surface• High-strength ceramics used for implants are very inert in the body and exhibit minimal ion release.• Aluminum oxide is regarded by many as the standard inert material……..
• The ionic ceramic surface is in a high oxidation state, thermodynamically stable and hydrophilic• Minimal ion release has been noted for aluminum oxide or zirconium oxide under normal conditions.• Coatings may also include biologic coatings such as proteoglycans, bone morphogenic proteins and growth factors
Zirconia• Zirconia (Zr02) is a ceramic material used in implantology because:• Biocompatibility(bio-inert)• Esthetics (because its colour is similar to the teeth)• Mechanical properties, which are better than alumina.• High resistance to corrosion, flexion, and fracture• Contact with bone and soft tissue similar to that observed in titanium implants• It can be used to produce a entire implant or as a coating.
Zygoma implants• The zygomatic implant is an alternative to bone grafting in extremely resorbed maxilla.• With extremely resorbed maxillae, fixed prosthesis can be provided with four zygomatic implants.• Either a conventional two stage procedure or a one-stage surgical procedure can be used
Zygoma implants
The four zygomatic implants procedure results in• Less morbidity,
• Shorter delays between anatomical reconstruction and
functional rehabilitation
• Provide immediate or early loading with immediate function.
• Four zygomatic implants and a fixed bridge seem to be a
valuable technique for the rehabilitation of extremely
resorbed maxillas.
