Emine ADALI1, Meltem Ozden YUCE2, Tayfun GUNBAY3, Godze GIPLAK4
- 1Research Assistant, Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Ege
University, Izmir, Turkey
2Research Assistant, Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Ege University, Izmir, Turkey
3Professor, Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Ege University, Izmir, Turkey
4Research Assistant, Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Ege University, Izmir, Turkey
Corresponding Author:
Dt. Emine ADALI,
Research Assistant
Ege University, Faculty of Dentistry,
Department of Oral and Maxillofacial Surgery Bornova, Izmir, Turkey
1Research Assistant, Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Ege University, Izmir, Turkey
Abstract
Aim: Recently, dental implant applications have become a routine treatment option in dentistry clinics due to their high success rate. The purpose of this study is to evaluate the success rates of different trademark dental implants applied in oral and maxillofacial surgery clinic between 2010-2015 and explain the reasons of failure.
Material and Methods: In this study; the results of dental implants applied to 271 patients who were treated in the Department of Oral and Maxillofacial Surgery of Ege University Faculty of Dentistry were evaluated. Clinical and radiological findings of the patients were recorded during the control sessions. Also; age and gender distribution of patients, distribution of systemic diseases and cigarette use, additional procedures performed before implantation, distribution and number of implants according to the time of application and post-tooth extraction time, distribution of implant losses and reasons were evaluated. In this study, implants that retained their functional and aesthetic continuity in the mouth were considered successful.
Results: In this study, a total of 272 patients were treated with 862 intrabony dental implants. 59,04% of the patients participating in the study did not have any systemic disease. 15,12% of the patients were actively smoking. An additional surgical treatment was required before implantation of 39.21% of implants. In this study, 23 implants were failed.
Conclusion: in the study, the loss rate of 862 implants 1-6 years was 2.668% and the success rate was 97,332%.
Key words: Dental implant: risk factors; success.
Introduction
In the past twenty years, the installation of dental implants as a treatment for tooth loss has become a predictable operation. Today, the determining factors for the unsuccessful use of implants are attracting attention, since its application is successful.
There are many factors that are responsible for the unsuccessful use of implants. Such factors as: demographic variables (age, sex), health variables (medical indications, dental indications, smoking, alcohol), anatomical variables (bone quality in the area of implant placement and quantity), options for prosthetic treatment, implant therapy planning, patient following-up and other factors (your keratin, gum volume, increased occlusal loading, oral hygiene)1, 2.
In studies evaluating the percentage of successful dental implants application, such criteria as the amount of osseointegration, bone implant support, implant mobility, infection, bone loss around the implant3, 4 were taken as a basis. However, in recent years, the criteria for evaluating the success of dental implant installation are estimated by the following criteria: the percentage of survival of implants in the oral cavity, the duration of prosthetic stability, the health of periimplant tissue, customer satisfaction, aesthetic and functional satisfaction5, 6, 7.
Minimizing the proportion of unsuccessful dental implant installations is an important issue for patient and physician comfort. Therefore, closer look of the risk factors that may affect the unsuccessful installation is necessary to plan the patient’s treatment in the most correct way.
The purpose of this study is to conduct a retrospective analysis of the unsuccessful dental implant installations of different brands that were installed by one doctor in the clinic for oral, maxillofacial surgery in 2010-2015, and the reasons for the unsuccessful cases.
Methods and Instruments
Present study was conducted in clinical conditions according to the results of different dental implant installations that were installed by one doctor in the clinic for oral, maxillofacial surgery of Dentistry Faculty of Ege University in 2010-2015. We have evaluated the results of intraosseous installation of a total of 862 dental implants in 271 patients (145 women and 126 men), which are followed-up in the clinic. Following implants were included in the study: 75 – ITI (Straumann, Basel, Switzerland), 36 – Biohorizons (Biohorizons LTD, Birmingham, USA), 39 – Astra Tech (Dentsply – Friadent, Mannheim, Germany), 57 – Bego (BEGO, Bremen, Germany), 41 – Alpha-Bio (Alpha-Bio Tec., Israel), 100 – Spectra (İmplant Direct, California, USA), 225 – Anthogyr (Anthogyr SAS, Sallanches, France), 81 – Biomet 3i (Zimmer-Biomet Dental, USA), 20 – Nobel, 93 – Frialit (Dentsply-Friadent, Mannheim, Germany), 95 – Bio 3 (Bio3 İmplants GmbH, Germany).
The planning of treatment for all patients was carried out on the basis of dental and medical history, clinical and radiological examinations. Based on this planning, all implant installations were performed by one doctor under local anesthesia in accordance with the basic principles. Patients were prescribed for 5-7 days from the date of implant installation to take antibiotic containing a combination of amoxicillin and clavulanic acid (for patients with penicillin allergy – an antibiotic containing clindamycin), and a mouthwash containing chlorhexidine gluconate. After 7-10 days after the operation, the stitches are removed, the clinical follow-up of the area where the operation was performed is carried out. For implants placed on the upper jaw, after 4-5 months, for implants placed on the lower jaw, after 3-4 months of the process of improvement, the gingival tissue above the implant was lifted and the crowns were fixed, after the tissue epulosis actions were taken for the prothetic treatment.
In cases where there was not enough bone for surgical procedures of dental implant installation, such techniques of bone grafting as bone graft installation, membrane application, lifting of the base of the maxillary sinus, autogenous bone graft (bone ring technique), split technique, osteoplastic technique. Implant installation based on the features in the area where bone augmentation was performed, was in the same session or after the graft was sufficiently integrated into the bone.
In the control sessions, the results of clinical and radiological examinations of patients were assessed and recorded. In the study, we considered implants successful, which functioned continuously in the oral cavity in terms of functionality and aesthetics. Also, the distribution by age and sex, the presence of systemic diseases and smoking, additional surgical procedures before implant installation, distribution and number of implants in the areas and the time of installation after tooth extraction, the distribution of loss of implants, and the reasons for this were also evaluated The analysis of the obtained data was carried out using descriptive statistics.
Results
In this study, a total of 862 intraosseous implants were installed in 271 patients (145 women, 126 men) aged from 20 to 79 years (Table 1). 59.04% of patients included in the scope of the study (women – 65.51%, men – 59.52%) had no systemic diseases. The distribution of patients with systemic diseases is given in Table 2. 15.12% of patients (women – 15.86%, men – 14.28%) are active smokers. 8 patients from those who smoke, have high blood pressure, 7 – cardiovascular diseases.
39.21% of patients who were diagnosed to install the implant, had to undergo an additional surgical procedure before implant placement. Of these additional surgical procedures, 43.78% – bone graft and membrane installation, 50.88% – sinus base increase, 2.36% bone-ring technique, 1.77% osteoplastic technique, 1,183% – splitting technique (Table 3).
50 implants were installed into the well after tooth extraction (immediately), 812 implants – installed in an area without a tooth with healed wound (immediately) (Table 4). The distribution of implants placed on the upper and lower jaw is very close to each other (Table 4). As a result of the assessment, 12.529% of the implants were placed in the anterior part of the mandible, 35.847% in the posterior part of the lower jaw, 15.313% in the anterior part of the maxilla bone, and 36.311% in the posterior part of the maxilla bone (Table 4).
18 patients (10 women, 8 men) of 271 included in the scope of study had total of 23 cases of implant loss. Among them 1 was lost due to infection at the stage of osseointegration (3 months after implant placement), and 18 – within 1 year after the occlusive loading due to periimplantitis. 11 patients among those who lost the implant because of periimplantitis, smoked. The 4 implants that were placed after the necessary treatment and beginning of treatment with bisphosphonate in the first year, were lost within 3 years after the occlusive loading.
Based on the collected data, it is seen that 1% of the implants installed in the holes after the tooth extraction were lost, and 2.58% from the implants installed in the healed area without a tooth. 21.74% of the lost implants were among the implants placed as a result of an additional surgical operation (the use of graft and membrane), 78.26% from implants that were installed without any surgical operation (Table 5). Also, the percentage of implant loss, based on the installation area, is shown in Table 5. As indicated in the table, most of the implant losts (34.78%) were in the posterior area of the lower jaw.
During the study, the ratio of lost implants of a total of 862 for 1-6 years was defined as 2.668%, and the ratio of successful installations – 97.332%.
Consideration
The success of dental implants installation has been proven by many researchers, and in the end, dental implant rehabilitation has become the main treatment option among clinical procedures8, 9, 10, 11. However, there is still possibility of unsuccessful implant installation, which also creates a problem for the patient, and for the doctor9. Up to this day, the percentage of success and failure in the installation of dental implants was evaluated based on many criteria12. As a result of the assessment it was found that 5-year success of treatment with dental implants is more than 95%13, 14. As a result of the evaluation carried out in 2015 by Moraschini and Ark, studies for at least 10 years, on which report on the success of the dental implant installation was made, were considered, as a result, the percentage of implant success in the oral cavity was confirmed in the amount of 94.6%12. In the same retrospective study, the success of implant installation was evaluated based on the continuous functioning in the oral cavity, functionality and aesthetics of implants, the result is determined in 97.332%.
The factors leading to the loss of the implant can be grouped into two groups. One of them is related to surgical technique, the type of implant, the place of installation – the time between implant installation and tooth extraction, the time between implant installation and occlusive loading. Other – systemic diseases (diabetes, cardiovascular disorders, etc.), smoking, other similar moments15.
The affect of systemic diseases on the installation of dental implants is not entirely clear, because the amount of studies with the control sample on the subject that have been published up to now, quiet not much16. One of these systemic diseases is diabetes17. Chronic hyperglycemia affects the synthesis of osteoblasts, enhances function of osteoclast18. Also metabolism of calcium and potassium changes 19. Such effect during cicatrization reduces bone formation, thereby may cause the loss of the implant during osseointegration. For this reason, diabetes is indicated as a relative contraindication for the installation of a dental implant20. On the other hand, successful implant installation ratio in diabetic patients with controlled glycemic index is close to the implant success rate in patients without systemic diseases17, 21, 22. In the scope of these studies patients with diabetes who controlled their glucose level in the blood had no implant loss.
Intravenous use of bisphosphonate is indicated as definitive contraindication for the installation of dental implants 23, 24. According to the references, patients who take oral bisphosphonate, the risk of osteonecrosis developing (BRONJ) of the jaw associated with the use of bisphosphonate in surgical operations when installing dental implant is low 16, 25, 26. As a result of the evaluation carried out by Diz and Ark it was found that 11 of 16 cases of BRONJ development after dental implant installation occurred with intravenous application of bisphosphonate, and the time between implant installation and development of BRONJ is on average 16 months 27. This study also indicates that the patient started to take oral treatment with bisphosphonate because of osteoporosis for 1 year, and then due to BRONJ, which developed for 3 years after the occlusive loading, 4 implants were lost.
Cardiovascular disorders are not characterized as contraindication for the installation of dental implants 27, 28. However, in retrospective study conducted by Manor and Ark, it is indicated that the loss of implants due to periimplantitis is higher in patients with cardiovascular disorders 16, 29. In the same study, it is not shown loss of implants in patients with cardiovascular disorders.
The performed study demonstrates that the risk of dental implant loss is higher in smokers 30, 31, 32, 33. As a result of the system assessment conducted by Chrcanovic and Ark, it is indicated that the percentage of dental implants loss in smokers is affected by the risk of periimplantitis and post-operative infections 32. It is considered, that the increase in implants loss rate in smokers is associated with the effect of cigarettes on osteogenesis and angiogenesis. Along with the significant effect of nicotine on the formation and remodulation of bones, it suppresses the formation of many enzymes that regulate the reproduction of osteoblasts, their differentiation, and apoptosis 34, 35. Also, the effect of nicotine disrupts the blood supply of tissues and nutrition with oxygen, which is local and systemic cardiovascular affect on blood vessels 36, 37. According to the references, 11 patients who experienced loss of the implant in a result of periimplantitis were smokers.
It is also stated that many studies indicate that the percentage of successful osseointegration of implants installed in the hole after tooth extraction is similar to the percentage of survival of implants that are installed in already healed areas 38, 39, 40, 41, 42. However, in some studies, it is stated that the percentage of losses of dental implants installed in the well after extraction is higher in comparison with implants installed in healed area without a tooth41, 43, 44. As a result of the evaluation performed by Chrcanovic and ark., it is indicated that the rate of loss of implants installed in the well after extraction, is 4.00%, and the rate of loss during installation in healed area without a tooth is – 3.09% 41. In this study, it is determined that the percentage of loss of implants installed in the well after removal is 4.00%, and the rate of loss during installation in healed area without a tooth is 2.58%, it is suggested that this difference is based on the fact that the number of implants installed in healed area without a tooth is significantly higher.
In the course of the studies conducted, it was shown that bone augmentation performed before dental implant installation does not affect the success of the implant installation 45, 46, 47, 48. The study carried out by Busenlechner and ark. Says that the implant success rate is 97% of patients who underwent elevation of the base of the maxillary sinus, 97% in patients underwent vertical and horizontal bone augmentation, 98% in patients underwent directed bone regeneration45. The study carried out by Anitua and ark. States that the chance of success during implant installation using the split kret technique is 96.8% 48. In this study, which corresponds to reference data, it is determined that implants installed after sinus base enhancement, bone ring technique, steoperiosteal flep technique, split kret technique, losses were not observed, and implant loss installed after the application of bone graft and membrane, was 3.37%.
The area in which implants are installed can also affect the percentage of implant losses. The study carries out by Alsaadi and friends indicates that the percentage of implant losses is higher for the posterior area of the upper and lower jaw compared to those in the anterior mandible 49, 50. In the study carried out by Busenkechner and ark. the percentage of implant success is defined in 94,8% for implants installed in the lower jaw, and 92,6% for implants installed in the upper jaw. Attention is also focused that there is no difference in the rate of lost implants for the anterior and posterior sections.
This study also shows that implant loss is maximum in the posterior section of the lower jaw, but in terms of the chance of implant loss, there is no definite difference for implants placed in the lower and upper jaw.
Results
In this study, the success of implant installation is assessed, based on the continuous functioning in the oral cavity in 1-5 years, the functionality and aesthetics of implants, the result is determined in 97.332%. In assessing the factors that are responsible for the failure of implant installation, it is concluded that, according to the references, smoking increases the risk of implant loss, the use of bisphosphonate may be a risk factor for implant loss.
It is also found that implants installed in the well after tooth extraction demonstrate similar results as implants installed according to normal procedure, and also that bone augmentation methods do not increase the percentage of implant loss.
Table 1: distribution of the number of patients and the number of implants.
Table 2: general medical condition of the patients
Table 3: Distribution of additional surgical procedures
Table 4: Distribution of implants according to installation time after tooth extraction and area of installation.
Table 5: Distribution of implant loss at the area of installation and the presence of additional surgical procedures.
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