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| Randolph R. Resnik, Dmd, MDS |
Randolph R. Resnik, DMD, MDS, talks about the popularity, success rate, and risks of immediate placement implants.
Q: Why have immediate placement implants become so popular?
A: Immediate implants are now in great demand because patients prefer “easier and faster” results. Patient acceptance of such treatment has grown due to a decreased treatment time, and because with this technique, only one surgical procedure is required. If the situation is ideal from an anatomical standpoint, the soft-tissue drape and bony architecture are both preserved by preventing post-extraction collapse during healing. However, even with all of these benefits, the clinician must still be aware that complications may occur.
Q: How does the success rate of immediate compare to the traditional surgical implant placement?
A: Controversy exists about the overall success rates of immediate implants, mainly due to the “one size fits all” approach that many clinicians follow. Some clinicians favor the delayed or staged approach, which consists of extraction, socket augmentation, and implant placement followed by an unloaded healing period. Many studies have shown that the success rates are similar between immediate and delayed placement. Yet, more clinicians are placing immediate implants into nonideal sites (ie, an infected extraction site). Not all cases are the same; immediate implant placement into compromised sites should be performed with caution, as the clinician may be vulnerable to medico-legal issues, should a complication occur.
Q: Do you believe too many immediate implants are being placed?
A: Most definitely! Clinicians must understand that this can be a much more complicated surgery than the staged approach. The extraction socket may or may not simultaneously encompass the ideal location of the implant. Also, there may not be sufficient bone to achieve rigid fixation. Modifications of the traditional surgical approach are often indicated to obtain ideal positioning. Combined with potential difficulties in soft-tissue closure, the surgery provides more surgical, prosthetic, and aesthetic difficulties, especially when the clinicians are in the beginning of their respective learning curves. The need to employ several additional skill sets is often challenging.
Q: How should the osteotomy preparation differ, with respect to anatomic location?
A: To avoid poor implant positioning with resultant aesthetic issues, the position of the immediate implants should be (1) within the lingual confines of the anterior teeth, (2) the center of the apical socket with premolars, and (3) within the interdental septum in molars. The most significant aesthetic complications result from anterior implants being placed too facial and too deep (apico-coronally).
Q: What should be a main area of concern for the clinician when placing immediate implants?
A: One of the most common causes of neurosensory impairment is an immediate implant in the mandibular first or second premolar site. To obtain initial stability of the implant after extraction, a common technique is to extend the osteotomy preparation 1.0 to 4.0 mm beyond the apex of the tooth. Studies have shown in approximately 28% of the population, the mental foramen is positioned superiorly to the apex of one of the premolars. Therefore, the mental foramen should be verified by CBCT examination, as the location of the foramen is highly variable; dependent on sex, ethnicity, age, and bone resorption.
Q: Are there any other areas of concern that may lead to serious complications?
A: Yes, mainly the maxillary and mandibular molar areas. The maxillary molar area is associated with possible complications because of the large socket (ie, first molar = mesial-distal diameter of 8.0 mm and buccolingual diameter of 10.0 mm), inherent poor bone quality, and multiple divergent roots. Additionally, studies have shown the mesial-buccal or palatal roots penetrate the sinus floor in more than 66% of the population. Thus, complications can result in implant failure or early/late implant migration into the maxillary sinus. The mandibular molar area may also place the clinician at risk. Especially in Type 1 nerves (mandibular canal in close approximation to root apex), osteotomy preparation to achieve rigid fixation may result in violation of the mandibular canal. The clinician must be fully aware (CBCT imaging) of the exact depth available to maintain a 2.0 mm safe zone from the canal.
Q: What problems does the failure of an immediate implant pose for a doctor?
A: When implants fail, they most likely will cause an osseous defect, which must then be grafted prior to replacement of the implant. This extends treatment time, leading to embarrassment and increased costs for the clinician, and also decreased trust on the part of the patient. In severe cases, pathology may occur, including the loss of adjacent teeth. In both situations, the clinician may be exposed to significant medico-legal ramifications.
Q: Why are immediate implants more susceptible to post-op infection than traditional techniques?
A: Increased risk of post-op infection is most commonly caused by the presence of bacteria from the extracted tooth. When active disease is present, the resultant decreased pH contaminates the dental implant with a bacterial smear layer, thus reducing bone formation. Additionally, this environment leads to solution-mediated resorption of graft material.
Q: Why is primary stability so crucial to the immediate implant process?
A: Micromovement of the dental implant will lead to fibrous encapsulation of the implant and unreliable integration. At the time of placement, primary implant stability is crucial. Care should be exercised in the premature loading of the implant with the use of an interim prosthesis.
Q: When should the clinician modify the treatment plan from immediate to the delayed approach?
A: During extraction, the clinician should always be observant of the bony architecture of the socket. If there was significant infection present or the socket is not intact (loss of buccal plate), primary implant stability becomes a significant issue. It is highly recommended to graft the site and proceed with implant placement after sufficient healing.
Q: What are the ideal conditions for an immediate implant?
A: To immediately place an implant after an extraction, the following should ideally be present: (1) a single-rooted failing tooth with healthy adjacent dentition, (2) atraumatic extraction leading to no destruction of the socket, (2) no active infection/purulent drainage, (3) five walls of remaining bone, (4) presence of healthy and harmonious gingival architecture, and (5) adequate available bone with no vital structures in close approximation to the apical area.
Dr. Resnik is a graduate of the University of Pittsburgh School of Dental Medicine with a specialty degree in prosthodontics, surgical fellowship in oral implantology, and a master’s degree in radiology. He is a professor at the University of Pittsburgh, Temple University, and Allegheny General Hospital, the surgical director of the Misch International Implant Institute, and maintains a private practice in Pittsburgh. He can be reached at rresnik@verizon.net.
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