- Email: [email protected]
disinfecting dental impressions
Methods.—A total of 12 patients (mean age: 48.8 years) had third attempts at implant placement in 15 sites. Their medical histories and smoking status were noted, along with implant dimensions, characteristics, and survival. All three attempts were made by the same surgeon using the same type of implant. Results.—The implants used for the three attempts were statistically the same in mean length and diameter. Although the implants were made by various manufacturers, they all had a medium rough surface. The first implant was lost after a mean of 7.6 months (range: 0.5 to 60 months). The second implant was placed a mean of 10 months (range: 0 to 30 months) after the first implant and lost after a mean of 7.4 months (range: 1 to 39 months). The third implant was placed a mean of 12.5 months (range: 2 to 31 months) after the second implant. Six of the 15 implants failed, for a survival rate of 60%. All failed in the first year after placement. None of the surviving implants was lost after the first year. Implant coating, the implant’s prosthetic connection, placement mode, premature exposure of submerged implants, and smoking habits showed no differences between the failed and surviving implants.
Discussion.—The first-year survival rate for the third attempt implants was only 60%, which is rather poor. It is considerably less than the survival rate of 71% to 88.3% for second attempts. In general, repeat surgery of any type tends to involve more complications. Both site-specific and patient-specific factors may enter into the process to produce this lower rate of success.
Clinical Significance.—It is important to know what the prognosis will be for implants, particularly if it is the second and certainly if it is the third attempt at placement. Both clinicians and patients need this information when considering treatment alternatives.
Machtei EE, Horwitz J, Mahler D, et al: Third attempt to place implants in sites where previous surgeries have failed. J Clin Periodontol 38:195-198, 2011 Reprints available from EE Machtei, Dept of Periodontology, School of Graduate Dentistry, Rambam Health Care Campus, Faculty of Medicine, Technion’ 11T, Haifa, Israel; e-mail: [email protected]
Infection Control Decontaminating/disinfecting dental impressions Background.—Decontamination and disinfection of dental impressions are required of dental practitioners before they send them on to the dental laboratory. However, impressions can arrive at the laboratory with visible contamination and inappropriate disinfection in many cases. As a result, dental technicians lack confidence that impressions are being decontaminated and disinfected and perform repeat procedures that can alter the surface detail and accuracy of the impression. Immersion and dipping are considered the most reliable ways to apply disinfectant agents. The current impression decontamination and disinfection practices and the relative prevalence of contaminated voids in apparently disinfected impressions were evaluated. Methods.—In all, 200 dentists and 200 dental technicians were randomly identified and asked to complete an anonymous postal questionnaire. The topics of the questionnaire were current practices and perceived effectiveness of impression disinfection. Results.—The return rate for the questionnaires was 42.1% among the dentists. A total of 75% of them worked in a general dental practice, with 11 respondents in specialty areas. With respect to disinfecting impressions, 94.9% always
did so, 3.8% sometimes did, and 1.3% never did. Water rinsing before disinfection was performed by 37.2% of the dentists, whereas 2.6% always brushed debris away. Many chemical solutions and concentrations were used to disinfect alginate and silicone impression materials (Table 1). Most dentists immersed their impressions, but some sprayed the agent on the surface. Mean immersion time was 9.18 minutes, with a range of 0.5 to 20 minutes. Notifying the dental laboratory that the impressions were disinfected was done by 75.3% of the dentists, but not by the rest of the sample. Bloodborne virus alerts were conveyed to the dental laboratory by 31.3% of the dentists, but not by 61.4%. The return rate for the questionnaires was 31.2% among the dental technicians. Among them, 81% said they rinsed the impressions with water when they received them, whereas the rest did not. Half of them disinfected the impressions in the dental laboratory, whereas the other half did not. In all, 50% of the technicians said that if the impression came from a patient with a bloodborne virus, it was so labeled by the dentist. In such cases, 46.4% of the technicians said they would redisinfect the impressions, whereas 53.6% said they would not. Among the respondents, 95% said that they received blood-contaminated impressions (Table 3). A
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2011
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Table 1.—The Names (as Stated by the Respondents) and, Where Stated, Concentrations of Chemicals Used to Disinfect Alginate and Silicone Impressions by the Respondent Dentists Chemical
Number
Concentrations used
Sodium hypochlorite1 Perform2 Sterilox3
8 65 10
Impressive Virkon Wright Unoguard Dimenol4 Aerosept5 Ethanol6 Presem Solution Mictan Durr7 Lometos Unident Impression8 Presept Impressive* Impressive Propan—2* Eurosept Max Impression* Virlon* Uno* Impression disinfectant spray*
13 5 2 2 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1
0.001%, 8%, MR 2%, MR 20%, 1:20 dilution, MR, 20 ml / 100 ml 60–90%, spray, MR 1%, MR 2% MR Ready-mixed 25% 10% One tablet / Litre, MR 60–90% MR -
Note: The materials quoted have, where possible, been grouped within the body of the table according to material type. * Chemical used only for silicone impressions by respondent(s). Abbreviations: MR, Dilution according to manufacturers’ recommendations; , no dilution stated. Agent type (if identified): 1, Hypochlorite; 2, pentapotassium bis(peroxymonosulfate); 3, hypochlorous acid (HOCl); 4, ampholytic surfactants, isopropyl alcohol; 5, hydrogen peroxide; 6, ethyl alcohol and chlorhexidine; 7, combination of aldehyde and quaternary ammonium compound; 8, quaternary ammonium aldehyde. (Courtesy of Almortadi N, Chadwick RG: Disinfection of dental impressions—Compliance to accepted standards. Br Dent J 209:607-611, 2010.)
total of 47% of technicians said they rarely encountered blood-contaminated voids when trimming the peripheral extensions of impressions, whereas for 15% this was a common or frequent occurrence. As to whether the dental technician always knew if the dentist disinfected the impression, 44.1% said they did and 55.9% said they did not. In all, 57% said they knew in some cases. A third of the respondents
Table 3.—Frequency of Blood-Contaminated Impressions Received by the Technicians Frequency of contamination
Never Seldom / rarely Commonly Frequently
Number of respondents
3 37 16 5
(Courtesy of Almortadi N, Chadwick RG: Disinfection of dental impressions—Compliance to accepted standards. Br Dent J 209:607-611, 2010.)
said they did not know how the impressions were disinfected, whereas two-thirds indicated that they did know. Dental technicians were not confident about the disinfection of impressions by the dentist based on having received impressions full of blood, a lack of written confirmation, a lack of verification, and impression trays contaminated with plaster. Discussion.—Guidelines indicate that the dentist is responsible for decontaminating and disinfecting impressions before they are sent to the dental laboratory. The results of this survey indicate that this is not always done and is often not communicated to the dental laboratory. Education in impression disinfection is needed for both dentists and dental technicians to improve compliance. Clinical Significance.—Dentists are charged with providing the dental laboratory with impressions that have been both decontaminated and disinfected. Although nearly 95% of the dentists indicated that they do disinfect impressions, there are clearly gaps in the communication process between them and the dental technicians. More training and standardized approaches should be instituted to ensure that this important task is not overlooked.
Almortadi N, Chadwick RG: Disinfection of dental impressions— Compliance to accepted standards. Br Dent J 209:607-611, 2010 Reprints available from RG Chadwick, The Dental School and Hosp, Univ of Dundee, Park Place, Dundee, DD1 4HN; e-mail: [email protected]
Medical Management Drugs for patients with chronic kidney disease Background.—The Centers for Disease Control and Prevention estimated in 2007 that 17% of the U.S. population had chronic kidney disease (CKD), which is known
188
Dental Abstracts
to develop after a progressive decline in glomerular filtration rate (GFR) until it is less than 15 mL/minute/1.73 m2 (Table 1). In managing patients with compromised kidney
Discussion.—The first-year survival rate for the third attempt implants was only 60%, which is rather poor. It is considerably less than the survival rate of 71% to 88.3% for second attempts. In general, repeat surgery of any type tends to involve more complications. Both site-specific and patient-specific factors may enter into the process to produce this lower rate of success.
Clinical Significance.—It is important to know what the prognosis will be for implants, particularly if it is the second and certainly if it is the third attempt at placement. Both clinicians and patients need this information when considering treatment alternatives.
Machtei EE, Horwitz J, Mahler D, et al: Third attempt to place implants in sites where previous surgeries have failed. J Clin Periodontol 38:195-198, 2011 Reprints available from EE Machtei, Dept of Periodontology, School of Graduate Dentistry, Rambam Health Care Campus, Faculty of Medicine, Technion’ 11T, Haifa, Israel; e-mail: [email protected]
Infection Control Decontaminating/disinfecting dental impressions Background.—Decontamination and disinfection of dental impressions are required of dental practitioners before they send them on to the dental laboratory. However, impressions can arrive at the laboratory with visible contamination and inappropriate disinfection in many cases. As a result, dental technicians lack confidence that impressions are being decontaminated and disinfected and perform repeat procedures that can alter the surface detail and accuracy of the impression. Immersion and dipping are considered the most reliable ways to apply disinfectant agents. The current impression decontamination and disinfection practices and the relative prevalence of contaminated voids in apparently disinfected impressions were evaluated. Methods.—In all, 200 dentists and 200 dental technicians were randomly identified and asked to complete an anonymous postal questionnaire. The topics of the questionnaire were current practices and perceived effectiveness of impression disinfection. Results.—The return rate for the questionnaires was 42.1% among the dentists. A total of 75% of them worked in a general dental practice, with 11 respondents in specialty areas. With respect to disinfecting impressions, 94.9% always
did so, 3.8% sometimes did, and 1.3% never did. Water rinsing before disinfection was performed by 37.2% of the dentists, whereas 2.6% always brushed debris away. Many chemical solutions and concentrations were used to disinfect alginate and silicone impression materials (Table 1). Most dentists immersed their impressions, but some sprayed the agent on the surface. Mean immersion time was 9.18 minutes, with a range of 0.5 to 20 minutes. Notifying the dental laboratory that the impressions were disinfected was done by 75.3% of the dentists, but not by the rest of the sample. Bloodborne virus alerts were conveyed to the dental laboratory by 31.3% of the dentists, but not by 61.4%. The return rate for the questionnaires was 31.2% among the dental technicians. Among them, 81% said they rinsed the impressions with water when they received them, whereas the rest did not. Half of them disinfected the impressions in the dental laboratory, whereas the other half did not. In all, 50% of the technicians said that if the impression came from a patient with a bloodborne virus, it was so labeled by the dentist. In such cases, 46.4% of the technicians said they would redisinfect the impressions, whereas 53.6% said they would not. Among the respondents, 95% said that they received blood-contaminated impressions (Table 3). A
Volume 56
Issue 4
2011
187
Table 1.—The Names (as Stated by the Respondents) and, Where Stated, Concentrations of Chemicals Used to Disinfect Alginate and Silicone Impressions by the Respondent Dentists Chemical
Number
Concentrations used
Sodium hypochlorite1 Perform2 Sterilox3
8 65 10
Impressive Virkon Wright Unoguard Dimenol4 Aerosept5 Ethanol6 Presem Solution Mictan Durr7 Lometos Unident Impression8 Presept Impressive* Impressive Propan—2* Eurosept Max Impression* Virlon* Uno* Impression disinfectant spray*
13 5 2 2 2 2 2 2 2 2 2 2 2 2 1 1 1 1 1
0.001%, 8%, MR 2%, MR 20%, 1:20 dilution, MR, 20 ml / 100 ml 60–90%, spray, MR 1%, MR 2% MR Ready-mixed 25% 10% One tablet / Litre, MR 60–90% MR -
Note: The materials quoted have, where possible, been grouped within the body of the table according to material type. * Chemical used only for silicone impressions by respondent(s). Abbreviations: MR, Dilution according to manufacturers’ recommendations; , no dilution stated. Agent type (if identified): 1, Hypochlorite; 2, pentapotassium bis(peroxymonosulfate); 3, hypochlorous acid (HOCl); 4, ampholytic surfactants, isopropyl alcohol; 5, hydrogen peroxide; 6, ethyl alcohol and chlorhexidine; 7, combination of aldehyde and quaternary ammonium compound; 8, quaternary ammonium aldehyde. (Courtesy of Almortadi N, Chadwick RG: Disinfection of dental impressions—Compliance to accepted standards. Br Dent J 209:607-611, 2010.)
total of 47% of technicians said they rarely encountered blood-contaminated voids when trimming the peripheral extensions of impressions, whereas for 15% this was a common or frequent occurrence. As to whether the dental technician always knew if the dentist disinfected the impression, 44.1% said they did and 55.9% said they did not. In all, 57% said they knew in some cases. A third of the respondents
Table 3.—Frequency of Blood-Contaminated Impressions Received by the Technicians Frequency of contamination
Never Seldom / rarely Commonly Frequently
Number of respondents
3 37 16 5
(Courtesy of Almortadi N, Chadwick RG: Disinfection of dental impressions—Compliance to accepted standards. Br Dent J 209:607-611, 2010.)
said they did not know how the impressions were disinfected, whereas two-thirds indicated that they did know. Dental technicians were not confident about the disinfection of impressions by the dentist based on having received impressions full of blood, a lack of written confirmation, a lack of verification, and impression trays contaminated with plaster. Discussion.—Guidelines indicate that the dentist is responsible for decontaminating and disinfecting impressions before they are sent to the dental laboratory. The results of this survey indicate that this is not always done and is often not communicated to the dental laboratory. Education in impression disinfection is needed for both dentists and dental technicians to improve compliance. Clinical Significance.—Dentists are charged with providing the dental laboratory with impressions that have been both decontaminated and disinfected. Although nearly 95% of the dentists indicated that they do disinfect impressions, there are clearly gaps in the communication process between them and the dental technicians. More training and standardized approaches should be instituted to ensure that this important task is not overlooked.
Almortadi N, Chadwick RG: Disinfection of dental impressions— Compliance to accepted standards. Br Dent J 209:607-611, 2010 Reprints available from RG Chadwick, The Dental School and Hosp, Univ of Dundee, Park Place, Dundee, DD1 4HN; e-mail: [email protected]
Medical Management Drugs for patients with chronic kidney disease Background.—The Centers for Disease Control and Prevention estimated in 2007 that 17% of the U.S. population had chronic kidney disease (CKD), which is known
188
Dental Abstracts
to develop after a progressive decline in glomerular filtration rate (GFR) until it is less than 15 mL/minute/1.73 m2 (Table 1). In managing patients with compromised kidney