REVIEW ANALYSIS & EVALUATION ARTICLE TITLE AND BIBLIOGRAPHIC INFORMATION Effects of tobacco smoking on the survival rate of dental implants placed in areas of maxillary sinus floor augmentation: a systematic review. Chambrone L, Preshaw PM, Ferreira JD, Rodrigues JA, Cassoni A, Shibli JA. Clin Oral Implants Res 2014; 25(4):408–416.
REVIEWER Liran Levin, DMD
PURPOSE/QUESTION The objective of this work was to evaluate the effects of smoking on the survival rate of dental implants placed in areas of maxillary sinus floor augmentation.
SOURCE OF FUNDING The study was self-funded by the authors and their institutions
TYPE OF STUDY/DESIGN Systematic review with metaanalysis of data
LEVEL OF EVIDENCE Level 2 Limited-quality, patientoriented evidence
Smoking May Decrease the Survival Rate of Dental Implants Placed in Areas of Maxillary Sinus Floor Augmentation SUMMARY Selection Criteria Both observational (case–control and prospective cohort studies) and interventional (randomized controlled clinical trials, controlled clinical trials, and case series) were included in the review.
Key Study Factor Studies were considered eligible for inclusion if they specifically involved the treatment of smokers and nonsmokers over age 18 years with titanium dental implants and sinus floor elevation procedures. Implant loss must have been recorded separately for smokers and nonsmokers.
Main Outcome Measure Number and/or percentage of implants lost.
Main Results The search strategy identified 3360 possibly eligible papers, of which 3349 were immediately excluded after the evaluation of titles and/or abstracts. The full text of the 11 remaining papers was assessed, and of these, one further paper was excluded because it did not meet the inclusion criteria (it did not separately report the outcomes on implant failure in smokers and nonsmokers). Data from two studies were reported in two articles each, thus, the early and later papers were cited under one study name. In total, 1129 patients, 1384 sinuses, and 3527 implants were reported in the 8 included studies. Seven studies were included in the meta-analyses. Random effects metaanalyses were done using dichotomous data (i.e., number of implants lost in smokers vs number of implants lost in nonsmokers). These were expressed as pooled risk ratios (RR) and associated 95% confidence intervals (CIs).
Conclusions STRENGTH OF RECOMMENDATION GRADE Grade B: Inconsistent or limitedquality patient-oriented evidence
Smoking was associated with implant failure in most of individual studies and in the overall meta-analysis. The detrimental effect of smoking did not reach statistical significance when only prospective data (limited to three studies) were assessed.
COMMENTARY AND ANALYSIS
J Evid Base Dent Pract 2014;14:183-184 1532-3382/$36.00 Ó 2014 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.jebdp.2014.10.001
Smoking has been related to various oral diseases, including malignancies, periodontal disease, and implant-related pathologies.1–6 During cigarette smoking, more than 7000 different gases and chemicals are released, including nitrogen, carbon monoxide, carbon dioxide, ammonia, hydrogen cyanide, benzene, nicotine, nornicotine, anatabine, and anabasine.7,8 Nicotine, considered the primary addictive component of
JOURNAL OF EVIDENCE-BASED DENTAL PRACTICE
cigarette smoke, has been implicated in the pathogenesis of numerous diseases.9,10 Carbon monoxide has a stronger affinity for hemoglobin than oxygen, resulting in displacement of oxygen from the hemoglobin and a lower oxygen tension in tissues.11 An estimated 42.1 million people, or 18.1% of all adults (age 18 years or older), in the United States smoke cigarettes.8 Cigarette smoking is more common among men (20.5%) than women (15.8%); overall smoking prevalence declined from 2005 (20.9%) to 2012 (18.1%), but tobacco use remains the single largest preventable cause of death and disease in the United States.8 In this systematic review and meta-analysis, it was confirmed that smoking was associated with failure of implants placed in areas of maxillary sinus floor augmentation. Although the level of evidence available is limited to some extent, the consistency between the available studies as well as the cumulative knowledge related to other locations of dental implant placement should serve as a warning sign regarding implant placement in smokers. Collecting and gathering data, as done in this paper, is of utmost importance when trying to draw accurate conclusions. Systematic reviews and meta-analysis are considered integral to promoting evidence-based decision-making. Thus this paper provides us with important information dealing with smoking and dental implants. Looking at the meta-analysis as presented on the forest plot, one can easily detect that all the included studies revealed higher implant failure rate among smokers, with a total effect risk ratio of 1.87 (95% CI: 1.35, 2.58). This means that after pooling the data from the selected papers, smokers showed an 87% higher failure rate than nonsmokers after sinus floor augmentation. Trying to learn some practical lessons from the information provided in this paper as well as that found in similar studies, dental practitioners should bear in mind and well inform implant patients about the increased risk for implant failure as well as peri-implant disease among smokers. Smoking cessation should be discussed with all smoking patients, especially those who are planning to have implants placed in their mouth. This does not mean that dental implants should be denied to smokers, but that they necessitate a thorough discussion and understanding of the risk for failure and complica-
184
tions as well as the benefit of smoking cessation. Careful explanation of the harmful effects of smoking and of the patient’s responsibilities in the attempt to achieve the best prognosis might improve the level of compliance. Unfortunately, while some patients complete the protocol successfully and stay off smoking for several months, the vast majority return to smoking. It is left to the discretion of the clinician to determine whether to undertake implant treatment in high-risk situations. Should the surgeon decide to go ahead, the patient’s fully informed consent is essential before proceeding.
REFERENCES 1. Atieh MA, Alsabeeha NH, Faggion CM Jr, Duncan WJ. The frequency of peri-implant diseases: a systematic review and meta-analysis. J Periodontol 2013;84(11):1586-98. 2. Levin L, Kessler-Baruch O. Cigarette smoking and the alveolar bone around teeth and dental implants. N Y State Dent J 2013;79(5):53-9. 3. Levin L, Ofec R, Grossmann Y, Anner R. Periodontal disease as a risk for dental implant failure over time: a long-term historical cohort study. J Clin Periodontol 2011;38(8):732-7. 4. Levin L, Hertzberg R, Har-Nes S, Schwartz-Arad D. Long-term marginal bone loss around single dental implants affected by current and past smoking habits. Implant Dent 2008;17(4):422-9. 5. Levin L, Baev V, Lev R, Stabholz A, Ashkenazi M. Aggressive periodontitis among young Israeli army personnel. J Periodontol 2006; 77(8):1392-6. 6. Levin L, Schwartz-Arad D. The effect of cigarette smoking on dental implants and related surgery. Implant Dent 2005;14(4):357-61. 7. Hoffmann D, Hoffmann I. The changing cigarette, 1950–1995. J Toxicol Environ Health 1997;50:307-64. 8. Centers for Disease Control and Prevention. Current cigarette smoking among adults—United States, 2005–2012. MMWR Morb Mortal Wkly Rep 2014;63(02):29-34. 9. Zevin S, Gourlay SG, Benowitz NL. Clinical pharmacology of nicotine. Clin Dermatol 1998;16:557-64. 10. Jorgensen LN, Kallehave F, Christensen E, et al. Less collagen production in smokers. Surgery 1998;123:450-5. 11. Leow YH, Maibach HI. Cigarette smoking, cutaneous vasculature, and tissue oxygen. Clin Dermatol 1998;16:579-84.
REVIEWER Liran Levin, DMD Head of Research, School of Dental Medicine, Rambam Health Care Campus and Faculty of Medicine, Technion, IIT, Haifa, Israel [email protected]
December 2014
REVIEWER Liran Levin, DMD
PURPOSE/QUESTION The objective of this work was to evaluate the effects of smoking on the survival rate of dental implants placed in areas of maxillary sinus floor augmentation.
SOURCE OF FUNDING The study was self-funded by the authors and their institutions
TYPE OF STUDY/DESIGN Systematic review with metaanalysis of data
LEVEL OF EVIDENCE Level 2 Limited-quality, patientoriented evidence
Smoking May Decrease the Survival Rate of Dental Implants Placed in Areas of Maxillary Sinus Floor Augmentation SUMMARY Selection Criteria Both observational (case–control and prospective cohort studies) and interventional (randomized controlled clinical trials, controlled clinical trials, and case series) were included in the review.
Key Study Factor Studies were considered eligible for inclusion if they specifically involved the treatment of smokers and nonsmokers over age 18 years with titanium dental implants and sinus floor elevation procedures. Implant loss must have been recorded separately for smokers and nonsmokers.
Main Outcome Measure Number and/or percentage of implants lost.
Main Results The search strategy identified 3360 possibly eligible papers, of which 3349 were immediately excluded after the evaluation of titles and/or abstracts. The full text of the 11 remaining papers was assessed, and of these, one further paper was excluded because it did not meet the inclusion criteria (it did not separately report the outcomes on implant failure in smokers and nonsmokers). Data from two studies were reported in two articles each, thus, the early and later papers were cited under one study name. In total, 1129 patients, 1384 sinuses, and 3527 implants were reported in the 8 included studies. Seven studies were included in the meta-analyses. Random effects metaanalyses were done using dichotomous data (i.e., number of implants lost in smokers vs number of implants lost in nonsmokers). These were expressed as pooled risk ratios (RR) and associated 95% confidence intervals (CIs).
Conclusions STRENGTH OF RECOMMENDATION GRADE Grade B: Inconsistent or limitedquality patient-oriented evidence
Smoking was associated with implant failure in most of individual studies and in the overall meta-analysis. The detrimental effect of smoking did not reach statistical significance when only prospective data (limited to three studies) were assessed.
COMMENTARY AND ANALYSIS
J Evid Base Dent Pract 2014;14:183-184 1532-3382/$36.00 Ó 2014 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.jebdp.2014.10.001
Smoking has been related to various oral diseases, including malignancies, periodontal disease, and implant-related pathologies.1–6 During cigarette smoking, more than 7000 different gases and chemicals are released, including nitrogen, carbon monoxide, carbon dioxide, ammonia, hydrogen cyanide, benzene, nicotine, nornicotine, anatabine, and anabasine.7,8 Nicotine, considered the primary addictive component of
JOURNAL OF EVIDENCE-BASED DENTAL PRACTICE
cigarette smoke, has been implicated in the pathogenesis of numerous diseases.9,10 Carbon monoxide has a stronger affinity for hemoglobin than oxygen, resulting in displacement of oxygen from the hemoglobin and a lower oxygen tension in tissues.11 An estimated 42.1 million people, or 18.1% of all adults (age 18 years or older), in the United States smoke cigarettes.8 Cigarette smoking is more common among men (20.5%) than women (15.8%); overall smoking prevalence declined from 2005 (20.9%) to 2012 (18.1%), but tobacco use remains the single largest preventable cause of death and disease in the United States.8 In this systematic review and meta-analysis, it was confirmed that smoking was associated with failure of implants placed in areas of maxillary sinus floor augmentation. Although the level of evidence available is limited to some extent, the consistency between the available studies as well as the cumulative knowledge related to other locations of dental implant placement should serve as a warning sign regarding implant placement in smokers. Collecting and gathering data, as done in this paper, is of utmost importance when trying to draw accurate conclusions. Systematic reviews and meta-analysis are considered integral to promoting evidence-based decision-making. Thus this paper provides us with important information dealing with smoking and dental implants. Looking at the meta-analysis as presented on the forest plot, one can easily detect that all the included studies revealed higher implant failure rate among smokers, with a total effect risk ratio of 1.87 (95% CI: 1.35, 2.58). This means that after pooling the data from the selected papers, smokers showed an 87% higher failure rate than nonsmokers after sinus floor augmentation. Trying to learn some practical lessons from the information provided in this paper as well as that found in similar studies, dental practitioners should bear in mind and well inform implant patients about the increased risk for implant failure as well as peri-implant disease among smokers. Smoking cessation should be discussed with all smoking patients, especially those who are planning to have implants placed in their mouth. This does not mean that dental implants should be denied to smokers, but that they necessitate a thorough discussion and understanding of the risk for failure and complica-
184
tions as well as the benefit of smoking cessation. Careful explanation of the harmful effects of smoking and of the patient’s responsibilities in the attempt to achieve the best prognosis might improve the level of compliance. Unfortunately, while some patients complete the protocol successfully and stay off smoking for several months, the vast majority return to smoking. It is left to the discretion of the clinician to determine whether to undertake implant treatment in high-risk situations. Should the surgeon decide to go ahead, the patient’s fully informed consent is essential before proceeding.
REFERENCES 1. Atieh MA, Alsabeeha NH, Faggion CM Jr, Duncan WJ. The frequency of peri-implant diseases: a systematic review and meta-analysis. J Periodontol 2013;84(11):1586-98. 2. Levin L, Kessler-Baruch O. Cigarette smoking and the alveolar bone around teeth and dental implants. N Y State Dent J 2013;79(5):53-9. 3. Levin L, Ofec R, Grossmann Y, Anner R. Periodontal disease as a risk for dental implant failure over time: a long-term historical cohort study. J Clin Periodontol 2011;38(8):732-7. 4. Levin L, Hertzberg R, Har-Nes S, Schwartz-Arad D. Long-term marginal bone loss around single dental implants affected by current and past smoking habits. Implant Dent 2008;17(4):422-9. 5. Levin L, Baev V, Lev R, Stabholz A, Ashkenazi M. Aggressive periodontitis among young Israeli army personnel. J Periodontol 2006; 77(8):1392-6. 6. Levin L, Schwartz-Arad D. The effect of cigarette smoking on dental implants and related surgery. Implant Dent 2005;14(4):357-61. 7. Hoffmann D, Hoffmann I. The changing cigarette, 1950–1995. J Toxicol Environ Health 1997;50:307-64. 8. Centers for Disease Control and Prevention. Current cigarette smoking among adults—United States, 2005–2012. MMWR Morb Mortal Wkly Rep 2014;63(02):29-34. 9. Zevin S, Gourlay SG, Benowitz NL. Clinical pharmacology of nicotine. Clin Dermatol 1998;16:557-64. 10. Jorgensen LN, Kallehave F, Christensen E, et al. Less collagen production in smokers. Surgery 1998;123:450-5. 11. Leow YH, Maibach HI. Cigarette smoking, cutaneous vasculature, and tissue oxygen. Clin Dermatol 1998;16:579-84.
REVIEWER Liran Levin, DMD Head of Research, School of Dental Medicine, Rambam Health Care Campus and Faculty of Medicine, Technion, IIT, Haifa, Israel [email protected]
December 2014
