An implant is one among the treatments to exchange missing teeth. Their use within the treatment of complete and partial edentulism has become an integral treatment modality in dentistry. Dental implants have a variety of benefits over conventional fixed dentures .
- A high success rate (above 97% for 10 years)
- A decreased risk of caries and endodontic problems of adjacent teeth
- Improved maintenance of bone in edentulous site
- Decreased sensitivity of adjacent teeth
An implant may be a structure made from alloplastic materials implanted into the oral tissues beneath the mucosa and/or periosteum and/or within or through the bone to supply retention and support for a hard and fast or removable dental prosthesis.
Implant dentistry is the second oldest dental profession; exodontia (oral surgery) is the oldest. Around 600 AD, the Mayan population used pieces of shells as implants to exchange mandibular teeth. In 1809, J. Maggiolo inserted a gold implant tube into a fresh extraction site. In 1930, the Strock brothers used Vitallium screws to exchange missing teeth. The subperiosteal implant was developed within the 1940s by Dahl in Sweden. In 1946 Strock designed a two-stage screw implant that was inserted without a permucosal post. The abutment post and individual crown were added after this implant completely healed. The specified implant interface at this point was described as ankylosis. In 1967, Dr. Linkow introduced blade implants, now recognized as endosseous implants. Dental implants became a scientific cornerstone after the serendipitous invention of Dr. Branemark who helped within the evolution of the concept of osseointegration (direct, rigid attachment of the implant to the bone with none intervening tissue in between two implants)
Anatomy and Physiology
A proper knowledge of anatomical landmarks and its variations before implant placement is indispensable to ensure a particular surgery and safeguard the patient against iatrogenic complications. The precise evaluation of distinct anatomical factors like the position of the mandibular canal, sinus , the width of the cortical plates, the prevailing bone density, etc. is extremely important in appropriate implant selection and planning the foremost appropriate implant position within the existing clinical condition. Important anatomical structures within the maxilla are a nasal floor, nasopalatine canal anteriorly and sinus posteriorly. Iatrogenic sinus perforation is usually encountered with complications. This problem is often taken care of selectively of short implants and Sinus lift and bone augmentation procedure.
The most important anatomical consideration while placing an implant within the mandibular arch is the location of the inferior alveolar canal which contains inferior alveolar nerve and artery. Injury to those vital structures during implant placement can cause pain, altered sensation, excessive bleeding, etc. Hence it’s important to work out the situation also because of the configuration of the mandibular canal before implant placement.
- Partial edentulous patients who have intermediate gaps or free-end edentulism
- When a patient isn’t satisfied with the prevailing unstable and nonretentive conventional complete dental implants prosthesis.
- To preserve existing removable partial prostheses.
- Disposable syringes
- Disposable surgical blades
- Towel clips
- Periosteal elevator
- Dental implants surgical kit (containing different drills)
- Physiodispenser with the surgical handpiece
- Dental implants
- Cover screw
- Healing abutment
- Needle holder
- Toothed tissue holding forceps
- Scissors, surgical sutures (in flap surgery)
- Soft tissue punch (for flapless surgeries)
- Types of implants and implant materials
Endosteal implants pierce just one cortical plate of maxilla and mandible. The foremost frequently used endosteal implant is the root form implant. The subperiosteal implant has an implant substructure and superstructure where a custom cast frame is placed directly beneath the periosteum. Transosteal implant crosses through both cortical plates.
Implants are often divided into three materials:
It is generally accepted that implant treatment is completed for restorative purposes. The importance of presurgical communication and cooperation between the restorative dentist, periodontist, denturist , and therefore the implant surgeon is well recognized in modern implantology. The predictable outcome of function and aesthetics of intraoral rehabilitation can and must be determined and controlled before the surgery , with the whole restorative team (the periodontist, surgeon, restorative dentist, laboratory, and patient). Competent interprofessional team-work is important for the successful completion of implant-retained restorations.
The implant placement should be restoration driven to satisfy the patient’s goals. The prosthesis should be designed first, almost like the architect designing a building before making the inspiration . Only after the prosthesis is made can the abutments, implant bodies, and available bone requirements be determined to support the specifically predetermined restoration.
The patient is medically evaluated for cardiovascular diseases (hypertension, congestive coronary failure , subacute bacterial endocarditis, etc.), endocrine disorders (diabetes mellitus, thyroid disorders, etc.), pregnancy, blood disorders, and bone diseases, etc.
Comprehensive and accurate radiographic assessment provides all necessary surgical Guides and prosthetic information required for the success of the venture. Various sorts of imaging modalities are used for implant imaging:
Computed tomography (medical CT and cone beam CT)
CBCT has a great role in dental applications
Surgical preparation in a standard sterile fashion is recommended for all implant procedures. The goal is to minimize mechanical and thermal injuries to the bone. Osteotomies should be completed under copious cool saline using sharp and new osteotomy drills at high torque and slow speed. Incremental drill sequence should be followed. During an osteotomy, the bone temperature should not exceed 47 degrees to avoid irreversible changes. Bone necrosis and failure of integration can occur when the temperature exceeds 47 degrees C. D1 bone presents the highest risk of overheating.
Surgical protocols: There are three surgical approaches which are in use over the years: (1) two-stage (2) one-stage, and (3) immediate-loading. The two-stage surgery first places the implant body below the soft tissue until the bone begins to heal (usually 2 to three months for mandible and three to six for maxilla). During the second stage of surgery, soft tissues are reflected to connect a permucosal element or abutment. In one-stage surgical approach, the implant body within the bone and therefore the permucosal element above the soft tissue are both placed simultaneously until initial bone maturation has occurred. The abutment of the implant then replaces the permucosal element without the necessity for a secondary soft tissue surgery. The immediate-restoration approach places the implant body and therefore the prosthetic abutment at the initial surgery, and restoration (mostly transitional) is then attached to the abutment.
Various complications and problems are often encountered during surgery and postoperatively. Perforated buccal or lingual plates are often seen during the procedure. Just in case of an elliptical /eccentric preparation, a wider implant is often used if possible. If not, pack the osteotomy with autogenous graft, compress it, and place the implant again. Bleeding within the floor of the mouth can occur from the arteria lingualis or arteria facialis injury. So absolute care has got to be taken during osteotomy preparation. Nerve injury can cause altered nerve sensation within the sort of anesthesia, paresthesia or hyperesthesia. Consequently, the surgical landmark is usually set conservatively 2mm above the mandibular canal.
The most common postoperative complication is incision line opening. the planning of the removable interim prosthesis is involved, it’s corrected. The patient is instructed to rinse 2-3 times daily with chlorhexidine. If the granulation process extends for quite a fortnight , epithelial margin trimming is often done. If implants become exposed during the healing period, no attempt should be made to hide them with tissue. Rather denture is relieved aggressively over the world with implant exposure. The mobility of the implant during healing is unusual but may occur, mostly amid a radiolucent zone round the implant. Whatever could also be the cause, the implant should be removed. Signs and symptoms of failure for an implant are horizontal mobility greater than 0.5 mm, rapid progressive bone loss, pain during percussion, uncontrolled exudate, generalized radiolucency round the implant, quite one half the bone is lost round the implant and last the implants inserted in poor position, making them useless for prosthetic support. A hit rate of 85%at the top of the 5 year period and 80% at the top of the 10 year period are minimum criteria for fulfillment.
The goal of recent dentistry is to revive the patient to normal profile, function, comfort, esthetics, speech, and health no matter the atrophy, disease, or injury of the stomatognathic system.
People live longer on the average . This fact, combined with an existing population of patients with minor and major dental problems, guarantees the longer term of implant dentistry for several generations of dentists. Dental implants increasingly want to replace single teeth, especially within the posterior regions of the mouth. Instead of removing sound tooth structure and crowning two or more teeth, increasing the danger of decay, endodontic therapy, and splinting teeth alongside pontics, which can have the potential to decrease oral hygiene ability and increase plaque retention, an implant may replace the only tooth.
Organized dentistry has finally accepted implant dentistry. The present trend to expand the utilization of implant dentistry will continue until every restorative practice uses this modality for abutment support of both fixed and removable prostheses on a daily basis because it is the primary option for all tooth replacements.