Immediate implant placement after tooth removal
Diagnosis and treatment planning are key factors in achieving successful outcomes after placing and restoring implants placed immediately after tooth extraction. Following some or all the following suggestions, depending on individual circumstances, should be considered when evaluating a patient for dental implants: thorough medical and dental histories, clinical photographs, study casts, periapical and panogram radiographs as well as a linear tomography or computerized tomography of the proposed implant sites. The most important step in treatment planning is determining the prognosis for the dentition, and prognosis for the tooth in question. Reasons for tooth extraction may include but are not limited to, insufficient crown to root ratios, remaining root length, periodontal attachment levels, status of furcations, periodontal health of teeth adjacent to the proposed implant site, un-restorable caries, root fractures with large endodontic posts, root resorption and questionable teeth in need of endodontic re-reatment.
Teeth requiring root amputations, hemi sections or advanced periodontal procedures may have a questionable prognosis and patients should be given reasonable options before these procedures are implemented. Similarly, the option for implant placement for non-vital teeth, fractured at the gingival margin with roots shorter than 13 mm should be considered as the treatment of choice. If treated using traditional methods, these teeth will require crown lengthening procedures, endodontic treatment, and posts and crowns. Removal of three or more millimeters of periodontal attachment during crown lengthening results in root length with less than optimal attachment. These factors are critical when teeth are being considered for abutments for fixed partial dentures. The risk to cost benefit ratio must also be considered.
Radiographic evaluation should consider availability of native bone, bone shape, quality, quantity, bone width and height. A minimum of 4-5 mm of bone width at the crest and 10 mm or greater from the alveolar crest to a safe distance above the mandibular canal is recommended.43 Sufficient distance must be available coronal to the maxillary sinus and floor of nose. For a satisfactory aesthetic result in the aesthetic zone, the interproximal bone height should be 5 mm or less when measured from the contact point of the adjacent tooth. As the distance from the contact point to the interproximal bone increases, the likelihood of retention of the interproximal papillae post implant placement diminishes. Patients must be made aware of potential aesthetic short-comings if implants are placed in jeopardized aesthetic zone sites. Once the decision has been confirmed that the patient is a candidate for immediate implant placement, a surgical guide should be used to assure proper implant placement. A provisional appliance with an ovate pontic should be avail- able for insertion after implant placement.
TOOTH EXTRACTION AND IMPLANT PLACEMENT
The patient is anaesthetized, and various flap procedures can be used to gain access for tooth extraction. Teeth to be removed and implants placed immediately after extraction can be accessed using either an open, flapped approach or with a minimally invasive technique. With experience the surgeon can displace the marginal tissues buccal/lingually to gain access to the surgical site. In the maxillary anterior region, it is important to avoid placing the implant directly into the extraction socket. Placement of the implant in this position will invariably cause the implant to perforate the buccal plate and jeopardize implant survival. The axis of the implant must be even with the incisal edges of the adjacent teeth or slightly palatal to this landmark. A direction indicator should be used to verify the correct angulation and trajectory of the proposed implant.
AFTER IMPLANT PLACEMENT
A healing abutment or cover screw is placed in the implant. The healing abutment should be even with or slightly apical to the adjacent marginal tissues. Interproximal papillae adjacent to the implant can be adapted with interrupted sutures under minimal tension. The provisional is then inserted, and evaluated, making certain the pontic is clear of the healing abutment. The provisional restoration should have an ovate pontic to support the adjacent tissues and help preserve soft tissue anatomy.
The patient is instructed in proper after surgery care and sutures are removed in seven to 10 days. Restoration of the implant can take place once osseointegration has been confirmed (maxillary anterior region four to six months). If an immediately placed implant would encroach upon the maxillary sinus, it might be prudent to delay implant placement, augment the sinus, allow for bone healing and then place the implant. The purpose of this paper was to review the rationale and treatment planning steps for implant placement immediately after tooth extraction. Multicenter studies have validated the predictability of placing implants at the time of extraction provided these procedures are appropriately treatment planned.