Modern implant placement, since its development in the 1960s, dental implant has become an increasingly popular treatment for dental patients around the world, with an annual estimated number of implant placed worldwide is 6.8 million implants, in the US is 910,000 implants*. In Vietnam, the first implant was placed in 1992 for a 54-year-old man who can still eat and chew well. It is estimated that in Viet Nam, about 20,000 to 40,000 implants are placed per year. In the past 22 years, dental implant has developed quite rapidly in Vietnam, Vietnamese doctors timely update the world implant techniques and perform all the techniques from simple to complicated. From easy cases with enough bone to complex cases with severe bone-deficiency, it is necessary to restore the bone by performing autografts with bone taken from the chin or pelvic area. In particular, lower alveolar nerve reposition and placing implants were successfully performed by Dr. Vo Van Nhan and reported at the Conference of Dental Implant in 2013. This is considered to be a breakthrough in Vietnamese dental industry [1].
Today, implant success in bone integration, meaning the implant fixed into bone after implantation is evident and has been proven in many studies, such as Lorenzoni's 100% [3] or Fugazzotto's 98.3 % [4]. However, a successful implant placement for cosmetic is a great challenge for clinicians. According to Jempt 1997 (JPRD journal) in the United States, studied 21 patients who were implanted in cosmetic zones (incisors of the upper jaw). The result after one year showed that only 58% of implants achieved cosmetic results, 42% of implants failed cosmetically, but all these implants were successful in bone integration (the implants still sit firmly in the bone).
One thing to note is that Dr. Jempt's research was conducted in the United States which is one of the most advanced dental education countries in the world, and the condition for physicians to be qualified is very strict and harsh. However, the rate of failure for cosmetic implants by the US doctors is very high at 42%, which means implants in the incisor area is very difficult to achieve cosmetic results, this is a tremendous challenge. So where does the problem come from and how to overcome it? What conditions should be fulfilled to achieve the desired cosmetic result when placing implants in the maxillary region?
Clinical signs of failure in cosmetic implant placement:
The first type is missing the interdental papilla, forming a gap between the two teeth (Figure 1). This is a common type, but this complication affects only patients with the gummy smile without significant effect on patients with low laughing lines, only expose teeth when laughing.
The second most severe cosmetic complication is the recession of gums exposing the implant (Figure 2). This is a completely cosmetic failure, upset both the doctors and patients. These cases also make doctors reluctant or have difficulty appointing implant treatment for the incisor area. This is a trap, a challenge for dentists in implant surgery.
Reasons:
There are three main types of causes of cosmetic failure: (1) indications errors, (2) technical errors, and (3) anatomical disadvantages. Causes (1) and (2) are due to the fault of the doctor, cause (3) is due to the adverse clinical condition of the patient.
- Indication errors: Due to the lack of careful examination of the patient's clinical condition resulting in immediate implant placement after extraction in patients with an cortical plate recession, patients with thin gum tissue, patients with dental infections, patients with low alveolar crest.
- Technical errors: Due to the inexperienced surgeon, placing the implant too close to the cortical plate, too deep, tilt too much, etc., placing the implant in the wrong position in the 3 dimensions orientational space. Do not graft bone when there is insufficient bone density to ensure that there is at least 2mm of bone surrounding the implant.
- Anatomical disadvantages: Patients with thin gum tissue, thin cortical plate, triangular teeth, infection, patients with many clinical diseases that reduce the ability to heal, etc.
Solutions:
According to Dr. Nhan, there are 5 important solutions: (1) Accurate clinical evaluation and careful treatment planning, (2) proper indications, (3) proper techniques, (4) ensure sufficient bone and gums volume, (5) experienced doctors, (6) cosmetic dental restoration.
- Clinical evaluation: This is a job that is often overlooked before the start of an implant, but in my opinion, this is the most important link affects all later decisions and treatment techniques. Careful clinical evaluation is require including: the bone status, type of bone loss, gingival tissue condition, inflammation of the implant area as well as adjacent areas as one infected tooth can spread and lead to implant failure. In addition, it is important to consider the shape of the adjacent teeth as well as the correlation between the bite joint and the opposite teeth. Only then the implanted teeth can later match and harmonious with the entire jaw as well as the smile of the patient. Furthermore, attention should be paid to general diseases and the patient's healing ability to choose the appropriate implants and materials. It is necessary to identify favorable factors to utilize as well as to detect the disadvantages and pitfalls to overcome. These must be discussed in advance with the patients so that they can understand and know the optimal cosmetic level that the doctor can give them and that he can not always deliver excellent results. Usually the following two trends when the clinical situation is too complex and too many disadvantages: First is that the patient has to perform many complicated procedures, using special materials which will increase costs and prolonged treatment time; Second, the patient has to lower his or her expectation to accept a simple and inexpensive solution in terms of cost and time. However, the third possibility is to accept a compromised solution between cosmetic and functional because the patient's condition is too complex and limitation of the current scientific methods and development.
- Proper indication: Avoid placing implant immediately after tooth extraction and no flap surgery, although no flap surgery will limit the impact on the patient it is difficult to predict the cosmetic results so indication should be very cautious, performed only when the following conditions are met: Patients with thick gum tissue, intact outer bone, low alveolar crest, square or oval teeth, etc. Most Asian patients in general and Vietnamese in particular have thin gum tissue so indication should be done very carefully in immediate implant placement.
In other cases, implant placement should be delayed 2-4 months after extraction. Depending on the type of bone loss, combining bone grafts and gum grafts to increase thickness, ensuring at least 2mm of bone surrounding the implant to ensure successful implant placement and long-term stability.
- Proper technique: Implants need to be placed in the correct 3-dimensional space in relation to the adjacent teeth, also the angle of the implant should be placed carefully, not angled too far outward or inward. Because when implanted tooth angled too far outward, it would be too long, too far inward, it would be too short cases. Both cause cosmetic loss.
- Sufficient bone and gums volume: This is considered to be a very important factor to ensure successful implant placement and cosmetic results that are stable in the long run. If sufficient bone and thick gums are good factors for good prognosis.
If there is a lack of bone or gum, the doctor will perform grafting these two types of tissue to ensure that there are 2mm of bones covering the implant and at least 1.1mm thick gum tissue and have interdental papillae around the implant. For this reason, most cases of implant placement in the cosmetic zone require additional gum and bone grafts.
- About the bone grafting material: Until now, the patient's real bone is still the best material because it contains growth factors that help heal wounds fast, have live bone cells and limit the rejection ability. Thus, in cases where there is a large amount of bone loss, the graft material has to be the patient's real bone which can be taken from the chin, jaw area, pelvic area. In cases where it is only a minor bone loss which requires less bone grafting, artificial materials can be used to replace bone.
- Experienced doctors: This is an extremely important condition that determines the success of the entire treatment process rather than the type of implant because each implant has its own pros and cons depending on the clinical situation of the patient, the doctor will choose the most appropriate one, and expensive implant does not mean it is good. Because formulating of an accurate treatment plan is important which depend on the experience of the doctor. Based on the examination and assessment of the gums and jaw bone condition, the doctor can determine the following issues: the number of implants and the type of implant to ensure firmness, treating the implant's surface for quick healing and choosing the type of dental prosthetics later on. Additionally, doctors also decide if the patient needs a bone graft or not and what type of grafting material is appropriate, for example: In the case of severe bone defects and severe bone loss, autograft using the patient's bone should produce good results. Artificial bone cannot be used in this case because it does not have growth factors like real bone. So the process of bone growth will be slow, sometimes does not provide enough bone for implant placement. Adhere to the principle of 2mm bone surrounding the implant for long-term success. Therefore, bone grafting in implant placement should be taken care of properly. In addition, strong gingival tissue also needs to be taken to consideration, even performing gum graft for implant placement to ensure it is not inflamed later. Thus, implant treatment is a chain of a continuous process including formulation of treatment plans, implant placement in the correct position and angle, bone and gum graft if necessary, not just choosing an implant or the implant placement.
- Cosmetic crown restorations: The cosmetic of the teeth in general or the teeth on the implants in particular, can be divided into two parts: pink cosmetic or cosmetic of the gum and white cosmetic or cosmetic of the teeth. The crown on the implant is the exposing part to everyone, so the cosmetic requirement is very important. If this part does not meet the requirement, the entire process is a waste. The crown must have the shape, color, and characteristics that harmonize with the adjacent teeth, with the patient's lips and smile as well as appropriate to the bite joint to be able to eat well.
In the following, we would like to introduce some cases of cosmetic failure due to not complying with the principles of implant treatment in the cosmetic zone:
- Case 1 (Figure 1) is a clinical case cited from Dr. Buser's paper. The mistake is due to implant placement in the wrong position, the implant was placed too close to the cortical plate, there were not enough 2mm of bone surrounding the implant, the implant was placed too deep, the patient had a thin gum tissue and the result was cortical plate resorption and gum recession and exposed the implant.
- Case 2 (Figure 2) is the clinical case of Dr. Rapoport in which the implant was exposed due to the same cause. Thus, these complications are also common among new colleagues starting implant treatment around the world and not only in Vietnam.
Here are two successful cases by complying with the principles of implant treatment in the cosmetic zone:
- Case 3 (Figure 3) is a clinical case done by Dr. Vo Van Nhan. This was a difficult case because the patient had an unfavorable clinical condition: bone resorption, thin gum tissue, and there were two adjacent implants. Therefore, the treatment plan in this case was implant placement with bone grafts using the bone of the patient combined with artificial bone, but grafted with special technique using real spongy bone of the patient grafted between the 2 implants to support the interdental papilla between 2 implants, while surgery increases the thickness of the gingival tissue and interdental papilla between the 2 implants.
- Case 4 (Figure 4): This is a case study done by Dr. Vo Van Nhan. This was an extremely difficult case because the patient suffered from severe bone loss both vertically and horizontally. Bone lack was clearly visible in clinical examination.
The treatment plan was to graft bone using the best material, in this case, was autograft using the bone of the patient taken from the inner jaw area rather than the artificial bone graft because of the large defect. This case also has successful results because of a good treatment plan that comply with principles of bone grafting, using the correct materials, implant placement in the right place, and at the same time, increase the thickness of the gum tissue.
* Conclusion: The above analysis showed that implant placement in the cosmetic zone is extremely difficult and challenging, requiring doctors to have a lot of experience, knowledge as well as supportive clinical skills such as bone, gum grafting. Not just implant placement. In addition, the examination of the patient's clinical condition must be thoroughly and carefully conducted to identify favorable factors to utilize, but more importantly, to detect unfavorable factors and pitfalls that can lead to failure to devise possible and practical solutions to overcome these factors before initiating treatment. Therefore, if you require dental implants, you should choose doctors with experience and have a thorough understanding and should not study and pick the brand of implant yourself because the implants themselves do not determine the entire treatment process as well as the long-term result because implant treatment result depends on too many factors and only experience doctors can have an overall view and resolve those factors.
Lastly, we wish all patients and colleagues always be happy and have a successful career and life.
Sincerely!
Ho Chi Minh City 8/8/2014
Vo Van Nhan DDS.PhD
1. Vo Van Nhan (2014), "Lower abdominal neuromuscular implant surgery and dental implants implantation: Clinical case report", Journal of Medical Research, Vol. 89-99. http://www.thanhnien.com.vn/pages/20131206/dot-pha-moi-ngong-nganh-implant-nha-khoa-viet-nam-in-thong-duoc-rang-nho-phau-thuat-doi- day-than-kinh.aspx.
2. Jemt T. (1997), "Regeneration of gingival papillae after single implant treatment", Int J Periodontics Restorative Dent, 17, pp.326-333.
3. Lorenzoni M, Pertl C, Polansky R, Wegscheider W. Guided bone regeneration with clinical barrier and radiographic follow-up study after 24 months. Clin Oral Implants Res 1999; 10 (1): 16-23.
4. Fugazzotto PA. Osseointegrated implants in function in regenerated bone for 72 to 133 months. Int J Oral Maxillofac Implants 005; 20 (1): 77-83.
5. D. Buser, U. Belser (2007), Implant therapy in the Esthetic Zone, Single Tooth Replacement, ITI Treatmet Guide, Quintessence Publishing Co.Ltd.