Smoking as a risk factor for dental implants and implant-related surgery

Cigarette smoking is known to adversely affect wound healing, and thus may jeopardize the success of dental implantation and implant-related oral surgery. The present study is aimed to present the influence of cigarette smoking on the success and survival of dental implantation as well as on the complication and success of implant-related surgery. We conclude that smokers undergoing both implant-related surgical procedures and dental implantation should be encouraged by their dentists, oral and maxillofacial surgeons, or treating physicians to cease smoking, emphasizing that smoking can increase complications and reduce the success rate of these procedures.     

Tobacco‐product usage as a risk factor for dental implants

The oral cavities of tobacco smokers and users of smokeless tobacco products are exposed to high concentrations of nicotine. A limited number of animal studies have assessed the effect of nicotine on osseointegration. Results from experimental studies have reported a statistically significant decrease, at 4 weeks of follow‐up, in bone‐to‐implant contact among rats exposed to nicotine compared with unexposed rats. Nicotine increases the production of inflammatory cytokines (such as interleukin‐6 and tumor necrosis factor‐alpha) by osteoblasts. Waterpipe, pipe, and cigarette smokers are at increased risk of developing oral cancer, periodontal disease, and alveolar bone loss. One explanation for this is that smokers (regardless of the type of tobacco product) are exposed to similar chemicals, such as nicotine, tar, oxidants, polyaromatic hydrocarbons, and carbon monoxide. Moreover, raised levels of proinflammatory cytokines have been identified in the gingival crevicular fluid of cigarette smokers with peri‐implant diseases. Therefore, it is hypothesized that nicotine and chemicals in tobacco smoke induce a state of oxidative stress in peri‐implant tissues (gingiva and alveolar bone), thereby increasing the likelihood of peri‐implant disease development via an inflammatory response, which if left uncontrolled, will result in implant failure/loss. In this regard, tobacco smoking (including cigarettes, waterpipe, and pipe) is a significant risk factor for peri‐implant diseases. The impact of vaping electronic cigarettes using nicotine‐containing e‐juices remains unknown. Habitual use of smokeless tobacco products is associated with oral inflammatory conditions, such as oral precancer, cancer, and periodontal disease. However, the effect of habitual use of smokeless tobacco products on the success and survival of dental implants remains undocumented.     

Tobacco and dental implants

Dental implants are the ideal standard of care for many oral health care providers. Tobacco use is an impediment to the success of this sophisticated procedure. Dentists who are trained to help their patients stop using tobacco are in position to improve their success rates with dental implants. A suggested protocol for tobacco cessation in the implant practice, if utilized, could raise the standard of health care in the dental office.     

Academic stress as a risk factor for dental caries

Objectives: To evaluate the associations between dental caries classified according to the index for decayed, missing and filled teeth (DMFT) and stimulated salivary flow, salivary capacity for oxidation reduction and academic stress in undergraduate dental surgery students aged 18–22 years. Methods: This research was performed at three time‐points: March 2010, September 2010 and March 2011. The sample was composed of 73 students, including 15 male and 58 female subjects. Data were obtained using the DMFT index to detect incident dental caries, the RD test Showa for salivary capacity for oxidation reduction, the Sisco academic stress inventory, and sterile polyethylene to stimulate salivary flow. Results: Logistic regression analysis showed that: subjects with stimulated salivary flow of < 1 ml/min are at increased risk for developing caries compared with those with stimulated salivary flow of ≥ 1 ml/min; those with moderate or high levels of academic stress are at greater risk for developing carious lesions than those with low academic stress; women are at greater risk for developing carious lesions than men, and, of the subjects studied, younger students were more likely to develop caries. Conclusions: Moderate to high levels of academic stress, younger age and lower salivary flow rate represent risk factors for the development of dental caries in students.     

Systematic review of survival rates for immediately loaded dental implants

The primary goal of this paper was to determine the survival rate of immediately loaded (IL) dental implants based on a systematic review of the literature. Secondary goals were to determine the influence of several factors on the implant survival rate, such as the type of reconstruction, implant location, and implant surface characteristics. An electronic search of databases was performed, in addition to a hand search of the most relevant journals. All relevant articles were independently screened according to specific inclusion criteria. The selected papers were reviewed. The literature search yielded 270 applicable articles up to December 2005. Of these, 71 met the inclusion criteria for qualitative data analysis. Eight articles were randomized controlled trials. The overall implant survival rate for the included studies was 96.39%. The database included 10,491 IL implants placed in 2,977 patients, with a maximum follow-up of 13 years. IL is well documented and predictable for the edentulous mandible (overdentures and full-arch prostheses) and for maxillary single crowns. Fewer data were found for maxillary full-arch reconstructions, fixed partial prostheses, and mandibular single crowns. For the latter two types of reconstructions, implants placed in anterior sites generally displayed a higher survival rate versus those placed in posterior sites. Rough surfaces displayed a higher survival rate than machined surfaces in all types of reconstructions. Most failures (97.1%) occurred within the first 12 months of loading. This review showed that it is possible to apply IL with excellent survival rates. Implant micromorphology and careful patient selection may affect treatment outcomes.     

Radiotherapy and the survival of dental implants: a systematic review

For patients with head and neck cancer, the effects of treatment with adjuvant radiotherapy can be devastating. Frequently there is loss of function due to tooth loss, pain and discomfort from xerostomia and mucositis, and a significant psychosocial impact. Dental implants provide an effective means of rehabilitation for many, but irradiation poses a unique set of challenges that can affect the outcome of treatment. The aims of this review were to find out whether radiotherapy in these patients affects the survival of dental implants, and to discuss details of pertinent influencing factors. An electronic search of the Medline, Web of Science, and CENTRAL databases was done to identify studies on the survival of implants in irradiated patients within specified inclusion and exclusion criteria. No restriction was placed on the year of publication. The primary outcome measure was implant survival. Seven studies involving 441 participants and 1502 implants placed into irradiated bone were included. Meta-analysis indicated that survival was significantly higher in the mandible compared with the maxilla (p = 0.04), and in non-irradiated cases compared with irradiated cases (p < 0.001). Other factors that showed a strong association with survival were radiation dose and timing of surgery. Implant-based rehabilitation is a viable option for head and neck cancer patients who have undergone radiotherapy. Whilst the short to medium-term implant survival in these cases is high, multiple factors require careful consideration for a favourable outcome. Further high-quality research and randomised controlled trials are required in this field.     

Human study of ion implantation as a surface treatment for dental implants

This clinical study evaluated a new surface treatment of ion implantation with CO ions which has previously been subjected to extensive study in animal models. The aim of this work was to assess its effect in humans. Experimental mini-implants were used; half of their longitudinal surface was machined and the other half was treated with CO ion implantation. The study was conducted in healthy volunteer patients who required prosthetic treatment with dental implants, and in accordance with the corresponding ethics committees. Coinciding with the insertion of commercial implants for oral restoration, one or two mini-implants were placed in the upper maxillary tuberosity or in the retromolar trigone of the mandible. The mini-implants were removed with a trephine jointly with a small volume of surrounding bone after a 3-month period. Two evaluation methods were used and both showed a greater degree of bone integration in the mini-implant section that underwent CO ion implantation treatment in comparison with the non-treated surface: 62.9% vs. 57.9%, and 54.8% vs. 46.2%. In addition, no adverse reactions were observed in the surface treatment with CO ion implantation. These results confirm the positive benefits in humans, based on the findings obtained from previous animal experiments.     

Damping factor for monitoring the bone interface at dental implants

OBJECTIVES: The aim of this study is to investigate whether the damping of osseointegrated implants, as measured quantitatively with the Osstell equipment, is related to the fractal dimension of peri-implant bone. MATERIAL AND METHODS: Fifty-five maxillary implants in function for 3 years before the present study were investigated. Two Osstell measurements were obtained for each implant with the transducer oriented first palatally and then distally. Using the half-power bandwidth method, the damping was calculated from the frequency/amplitude plot obtained from the Osstell. Damping data were then related to the fractal dimension of peri-implant bone. Fractal dimensions were calculated using a box-counting algorithm on digitally processed intra-oral radiographs of the implants. A Spearman's test was used to verify the correlation between damping and fractal dimension values. RESULTS: All the implants were clinically stable and free from symptoms. The mean ISQ was 63 for the palatal orientation and 71 for the distal orientation. The mean fractal dimension was 1.47; the mean damping value for palatal orientation was 12.3%, while that for the distal orientation was 8.2%. No significant correlation was found. CONCLUSIONS: Damping values, measured at peri-implant bone, were found not to be related to a radiographic parameter of trabecular bone pattern like the fractal dimension. The clinical implication would be that Osstell graphs displaying distinct or more rounded peaks might both indicate a stable implant as long as the associated implant stability quotients are in the range of satisfactory values proposed in the literature.     

Significance of occlusion for dental implant treatment. Clinical evidence of occlusion as a risk factor

It is believed that one of the potential risk factors for peri-implant bone loss and failure of the implant /implant prosthesis may be occlusal overloading. Overloading factors, e.g parafunctions, may negatively influence on implant longevity, however, It must be emphasized that currently there is little evidence regarding implant failure caused by overloading. The purposes of this paper are to discuss the importance of implant occlusion for implant longevity and to provide possible solutions managing complications related to parafunctions. This paper summarizes the lecture presented at the International Congress of Prosthodontics 2007 in Kobe.     

Aspirin, a risk factor for bleeding at dental procedures

Aspirin is widely used as an antithrombotic drug in the prevention of cardiovascular events. It causes a usually mild bleeding tendency. When used before dental or surgical procedures, aspirin increases the risk of bleeding, contrary to the postoperative administration of aspirin, which has not been associated with increased risk of bleeding. To estimate the risk of bleeding, a history on bleeding tendency and information on the recent use of aspirin is worthwhile. It is recommended to delay procedures for at least one week after the last ingestion of aspirin, if possible. In case of urgent surgical procedures or in patients who suffer from serious bleeding due to the use of aspirin, a single preoperative transfusion of a suspension of platelets is usually sufficient to antagonize the effects of aspirin. Tranexamic acid can be given alternatively. The preferred policy depends on the type of the procedure to be performed, or the nature of the bleeding.     

Success and survival of single dental implants placed in sites of previously failed implants

BACKGROUND: The aim of this study was to assess the clinical effectiveness of single dental implants placed in sites of previously failed implants. METHODS: The study consisted of a consecutive cohort of 1,215 patients who received 1,387 single implants for single-tooth replacement during a 6-year period (1999 to 2005). Inclusion criteria were a single implant replacing a previously failed implant and follow-up data > or =6 months. Data were recorded and analyzed regarding implant survival and location, need for bone augmentation, and implant dimensions. RESULTS: A total of 75 patients experienced the failure of 96 implants. Of those, 31 implants in 28 patients were replaced by a similar implant placed in the same location. Nine of the replacement implants failed, resulting in an overall survival rate of 71%. Follow-up ranged from 6 to 46 months (mean, 19.4 +/- 11.4 months). Replacement of maxillary and mandibular failed implants was similar. All failures occurred during the first year after implant replacement. On average, implant replacement occurred 5.8 +/- 5.2 months after original implant removal; three implants were placed immediately after implant removal. A third attempt for single implant replacement was made in two patients. However, one failed. CONCLUSIONS: Replacement of a failed implant presents a challenge to achieve osseointegration in a healed bone site and may result in a decline in the survival rates. Patients and clinicians should be aware of these results before a replacement attempt is considered. The success of replacement may be increased by the use of wider implants or with improved surfaces.     

Selective serotonin reuptake inhibitors as a risk factor for dental implant failure: a retrospective clinical study

The trend in recent decades in Europe and the United States points to an exponential increase in the consumption of antidepressant drugs and, in particular, selective serotonin reuptake inhibitors (SSRIs). This retrospective study aimed to investigate whether there is an association between SSRI intake and dental implant (DI) failure or survival and, secondarily, to investigate the influence of other systemic and local factors. This retrospective cohort study was done in accordance with the the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) guidelines for observational studies. A total of 170 patients received 573 DIs between 2014 and 2020.The reported DI failure rate was 6.11% (n = 35 DIs). Of these 18.31% failed in patients treated with SSRIs while 4.38% failed in patients who were not prescribed SSRIs (p < 0.001). Specifically, use of these drugs was associated with a hazard ratio rate of DI failure that was 4.53 times higher (95% CI: 1.93 to 10.61), and in the multivariate analysis, a 3.70 times higher adjusted risk was found. A lower DI survival rate at 90 months’ follow up was also observed in these patients compared with those not taking them (84.30% vs 96%, respectively; p = 0.00014). With the limitations of the present study it can be affirmed that there is a relation between the intake of SSRIs and DI failure, as well as a lower survival rate in these patients.     

Smoking as a risk factor for periodontitis

Smokers have a higher susceptibility for periodontitis than non-smokers. Smoking is associated with more loss of attachment, progressive periodontal breakdown and also with a poor response to periodontal treatment. This is caused by the direct effect of nicotine on several factors that play a bacterial attack. These factors include the gingival vascularization and cellular defense mechanisms. The periodontal status of former smokers is intermediate to that of those who have never smoked and current smokers. Smoking cessation seems to have a beneficial effect on periodontal health.     

Rationale for dental implants

The clinical replacement of lost natural teeth by osseointegrated implants has represented one of the most significant advances in restorative dentistry. Two decades ago, a majority of dentists were sceptical about implants and rejected them entirely. Today it is rare to find a practitioner who does not work with dental implants or who is not actively participating in one of the many seminars or courses offered by universities, professional societies and implant manufacturers.