720 likes | 1.07k Views
OVERVIEW OF DENTAL IMPLANTOLOGY Dr. Deborah M. Ajayi Consultant Restorative Dentistry, University college Hospital, Ibadan. Edentulous spaces.
E N D
OVERVIEW OF DENTAL IMPLANTOLOGY Dr. Deborah M. Ajayi Consultant Restorative Dentistry, University college Hospital, Ibadan.
Implantology is the science of implanting foreign (alloplastic) materials to replace endogenous (lost) organ functions with the objective of tissue-friendly setting (biointegration). • A Dental Implant is a device inserted into or on the jaw bone to anchor an artificial tooth or denture (prosthesis). • A root analog. Introduction.
Mayan civilization first used the earliest known endosseous implant over 1400 years ago. In 1931, Archaeologists from Honduras confirmed it. In 1950, Researchers at Cambridge University implanted a chamber of titanium in rabbit’s ear. In 1952, Swedish Orthopaedic Surgeon I-P Branemark implanted titanium rabbit femur. In 1952, Dr. Leonard Linkow at the New York University College of Dentistry placed his first dental implant. In 1965, Branemark placed his 1st titanium dental implant. 1960s – Sub-periosteal implants introduced. 1970s– Blade implants was in vogue. Historical background
Mucosal Insert • Endodontic Implant (Stabilizer) • Transosseous implant • Sub-periosteal implant • Endosteal or Endosseous implant Types of implant
Endodontic Implant (Stabilizer) • Endodontic implants are similar to prosthodontic implants in many respects. • However, they serve another purpose—the stabilization and preservation of remaining natural teeth, not the replacement of lost teeth.
Transosteal implants • Placed through the mandible (only) • Attachments reside above ridge • Rarely used
Subperiosteal implant • rests on alveolar ridge, no bone invasion • Less invasive, • less stable • Supports denture
Endosseous • 3 types; plate/blade form, ramus frame and the root form-(Most common) • Placed in the bone • Single tooth or multiple teeth replacement • Screwed or non screwed • Cylindrical or tapered • Surface treatment • Grit blasting, plasma sprayed etc
Branemark’s Osseointegration. • Prof Branemark • Root form implants • Improved the designs & techniques • Reports of success rates from over 15 years experience. • Improved understanding
A direct structural and functional connection between ordered living bone and the surface of a treated implant, which is visible under the light-optical microscope. (Branemark 1952) • A time-dependant healing process where by clinically asymptomatic rigid fixation of alloplastic materials is achieved, and maintained, in bone during functional loading. (Zarb & Albrektson,1991) • Relies on an understanding of • Tissue healing and repair • Tissue remodelling • Effects of force in all vectors • Immune response to the insertion of foreign bodies. Osseointegration
Implant biocompatibility Implant design Implant surface Implant bed Surgical technique Loading condition Factors affecting osseointegration
Similar soft tissue relationship to natural dentition(sulcular epithelium) Hemidesmosome like structures connect epithelium to titanium surface Circumferential and perpendicular connective tissue No connective tissue insertion No intervening sharpey fiber attachment Outcome of Osseointegration
Osteoblast is in close proximity to interface Separated from implant by thin amorphous proteoglycan layer Oxide layer continues to grow- mineral ion interaction Increase in trabecular pattern Bone deposition and remodeling in response to stress. Bone-implant interface
Usually a metal or alloy which must be biocompatible, strong and lightweight. • Most commonly used • Commercially pure titanium (CP titanium) • Lightweight, Biocompatible,Corrosion resistant, Strong and low priced • Titanium-aluminum-vanadium alloy (Ti-6Al-4V)- stronger and used with smaller diameter implants • Zirconium • Hydroxyapatite (HA), one type of calcium phosphate ceramic material Implant material.
Advantages of Dental implant Disadvantages of Dental Implant. • No preparation of adjacent teeth. • Bone stabilization and maintenance • Retrievability • Improvement of function • Psychological improvement • May be fixed or removable. • High level of predictability. • It can last for a life time. • Involves elective surgery. • High operator/technique dependent. • High initial expense. • Lengthy treatment time. • Requires some moderate maintenance. • Depends on the availability of adequate bone quantity and quality. • Challenging aesthetic
Indications of Dental Implants Contraindications • Good general health • Adequate bone quality and volume • Appropriate occlusion and jaw relations • Inability to wear conventional prosthesis • Unfavourable number/location of abutment • Single tooth loss • Unrealistic patient expectations • Alcohol/drug dependence and smoking • Parafunctional habits • Psychological factors • Inadequate ridge/inter-arch dimensions • Immunosuppression • Diabetes (Uncontrolled) • Coronary artery Disease • Drug therapy: e.g Anticoagulants • Osteoporosis n
Replacement of lost tooth teeth due to : • Trauma,(Avulsed tooth, fractured tooth,etc) • Dental disease (gross caries, endodontic failures, periodontitis etc) • or developmental abnormalities(congenitally missing tooth,). • To overcome problems of free end saddle • Anchorage for orthodontic tooth • Single tooth replacement • Fixed multiple tooth loss- Implant retained bridge prosthesis • Completely edentulous patients – implant retained removable dentures. ApplicationS of Dental Implant
Patient Education. • Treatment options • Multidisciplinary approach. • Long-term commitment • Surgical and Restorative procedures • Maintenance and regular recall • Fee and payment policy • The inform consent. Initial evaluation of the patient
General Health : • History : Dental, Medical, Social and Habit • Examination ; • Laboratory investigations • Predictable risks Assessment
Teeth Periodontium Radiographic analysis Surgical analysis Aesthetic analysis Occlusal analysis Dental evaluation
Number and existing condition: • Minimum 6-7mm between teeth to facilitate implant placement • >1.5mm between implant and natural teeth • 7mm from centre of implant to centre of implant for edentulous • More than 10mm mesiodistal space- single tooth implant not recommended • Prognosis of remaining teeth • Tooth and root angulations and proximity • Mesiodistal width of the edentulous space Teeth
According to Lekholm and Zarb.,1985 classified bone quality as: Type I Composed of homogenous compact bone, usually found in the anterior mandible Type II A thick layer of cortical bone surrounding dense trabecular bone, usually found in the posterior mandible Quality III A thin layer of cortical bone surrounding dense trabecular bone, normally found in the anterior maxilla but can also be seen in the posterior mandible and the posterior maxilla. Quality IV 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 maxilla. It can also be seen in the anterior maxilla. Periodontium and bone support
6mm or below buccal-lingual width with sufficient tissue volume. 8mm interradicular bone width 10mm alveolar bone above IAN canal or below maxillary sinus Bone quantity for implant.
There is need for sufficient tissue volume to create gingival papilla Need some attached gingiva to maintain peri-implant sulcus The implant is placed 2-3mm apical to free gingival margin of adjacent tooth/teeth. Mucogingival evaluation
Radiographs : periapical, occlusal, panoramic and CT scan or tomograph as indicated. • CT gives more accurate and reliable assessment of bone • Assess • Periapical pathology • Adequate vertical bone height • Adequate space above IAN or below the maxillary sinus • Adequate interradicular area • Bone quality and quantity Radiographic analysis
Aesthetic analysis • Smile line • Lip shape • Existing ridge • Restored implant should appear to emerge from the gingiva • Produce a natural and desirable appearance
Occlusal analysis • Assess for parafunctional habit: • tooth lost to occlusal trauma or parafunctional habit is less successful with implant • Diagnostic cast is produced and mounted to determine opposing occlusion
Implant surgery • Single stage • Two stages • Placement of Implant • Immediate • Standard • Delayed • Implant loading • Immediate • Delayed IMPLANT treatment
Pre-operative medication • Local Anaesthetic with or without general sedation • Analgesics, such as ibuprofen or paracetamol can be administered immediately prior to surgery. • Sterile environment should be maintained throughout the surgery. • Chlorhexidine 0.2% is used as a pre-operative mouthwash and skin preparation. Surgical procedure
A mid-crestal incision with vertical relieving incisions (if closed to adjacent teeth including inter-dental papilla). A mucoperiosteal flap is raised. The flaps should be elevated sufficiently far apically to reveal any bone concavities, especially at sites where perforation might occur. Surgical procedure cont.
Edentulous jaw for implant Markings for incision i
Mid crestal incision Mucoperiosteal flap .
It is essential not to allow the bone to be heated above 47°C during preparation of the site as this will cause bone cell death and prevent osseointegration. • This problem may be avoided by: • Using sharp drills • Incremental drilling procedure with increasing diameter drills • Avoidance of excessive speed • Using copious sterile normal saline irrigation. Bone preparation.
Preparation commence with Initial penetration. • Pilot drill
guide pin is placed to check the direction Check the final depth with a depth gauge
Check the spacing and angulation of the implant sites carefully with direction indicators throughout the drilling sequence Angulations of the implants should be consistent with the design of the restorations Implant spacing and angulation
Implant should be placed such that; • It is within bone along its entire length. • It does not damage adjacent structures such as teeth, nerves, nasal or sinus cavities. • Multiple implants sholud be placed in fairly parallel arrangement. • The top of implant should be placed sufficiently under the mucosa to allow a good emergence profile( eg 2-3mm apical to labial CEJ of adj. Teeth) Implant placement
Allowances should be made between the implant and the following structures:
Implant insertion • The implant is supplied in a sterile container, either already mounted on a special adapter or unmounted necessitating the use of an adapter from the implant surgical kit. • In either case the implant should not touch anything before its delivery to the prepared bone site.
Cylindrical implants are either pushed or gently knocked into place. • Screw shaped implants are either self tapped into the prepared site or inserted following tapping of the bone with a screw tap.
Wound closure • The mucoperiosteal flaps are carefully closed with multiple sutures either to bury the implant completely or around the neck of the implant in non-submerged systems. • Silk sutures are satisfactory and others such resorbables are good alternatives.
Post op radiograph • Take Postoperative radiographs(Periapicals) to evaluate implant position in relation to adjacent structures. • Also for monitoring the ossteointegration.