- Email: [email protected]
Electric versus air-turbine handpieces
Fig 4.—Postoperative OPG of patient from Fig 3 following radical debridement and removal of teeth. (Courtesy of Williamson RA: Surgical management of bisphosphonate induced osteonecrosis of the jaws. Int J Oral Maxillofac Surg 39:251-255, 2010.)
Fig 7.—Clinical picture of left mandible of multiple myeloma patient from Fig 5 showing healthy soft tissues overlying site of previous ONJ. (Courtesy of Williamson RA: Surgical management of bisphosphonate induced osteonecrosis of the jaws. Int J Oral Maxillofac Surg 39:251-255, 2010.)
Clinical Significance.—Support for the surgical management of ONJ unresponsive to conservative measures is growing in the literature. It should be anticipated that some cases will be resistant to all treatment, but the current follow-up duration is insufficient to reveal these.
Fig 5.—Follow-up OPG of patient with multiple myeloma from Fig 4, 1 year after radical debridement, showing the bone in the left mandible and right maxilla has healed with new bone formation. (Courtesy of Williamson RA: Surgical management of bisphosphonate induced osteonecrosis of the jaws. Int J Oral Maxillofac Surg 39:251-255, 2010.)
irregular bony areas, and tension-free primary closure of the wound site under antibiotic coverage preoperatively and after surgery.
Williamson RA: Surgical management of bisphosphonate induced osteonecrosis of the jaws. Int J Oral Maxillofac Surg 39:251-255, 2010 Reprints available from RA Williamson, Dept of Oral Surgery, Faculty of Medicine and Dentistry, Univ of Western Australia, 17 Monash Ave, Perth, WA 6009, Australia; fax: þ61 8 9346 7623; e-mail: [email protected]
Dental Equipment Electric versus air-turbine handpieces Background.—The primary tooth-cutting instrument used in the United States is the high-speed air-turbine handpiece, but electric-motor handpieces are often used in other parts of the world. Seldom are the cutting efficiencies of these two handpiece types compared. The cutting efficiencies of air-turbine and electric-motor
handpieces were evaluated using seven different dental materials. Methods.—Blocks of machinable glass ceramic (Macor), silver amalgam, aluminum oxide, zirconium oxide, high noble metal alloy, noble metal alloy, and base metal
Volume 55
Issue 4
2010
185
significant interaction between material type and handpiece used with respect to cutting efficiency was found (Fig 3). The electric handpiece was more successful than the air-turbine handpiece in cutting high noble metal alloy, silver amalgam, and machinable glass ceramic. No difference in cutting efficiency was found for the other materials.
0.05 Air turbine
Cutting Efficiency
0.04
Electric 0.03 0.02 0.01
y
H
ig
h
no
Al
bl
e
Am al ga m
lo al al et
um um
in
m
id ox
al al et m e
Ba s
M ac or
e
y lo
e id ox um ni
rc o Zi
N
ob le
m et
al al lo y
0
Discussion.—There was a significant difference in the cutting efficiency of the electric and air-turbine handpieces. The different materials also demonstrated significant cutting efficiency differences. The material cut and the handpiece used showed a significant interaction, with the electric handpiece significantly better than the air-turbine handpiece in cutting high noble metal alloy, silver amalgam, and machinable glass ceramic.
Fig 3.—Interaction between handpieces and materials tested. Error bars signify standard deviations. (Courtesy of Choi C, Driscoll CF, Romberg E: Comparison of cutting efficiencies between electric and air-turbine dental handpieces. J Prosthetic Dent 103:101-107, 2010.)
alloy were each cut using a bur 110 times with an electric handpiece and 110 times with an air-turbine handpiece. The weight of the material after the cut was compared with the weight before the cut to determine the weight difference, which was then divided by the duration of the cut (g/s) to yield the cutting efficiency. The results were analyzed statistically. Results.—The electric handpiece proved to be significantly more efficient than the air-turbine handpiece for cutting the various dental materials. The high noble metal alloy was cut most efficiently, followed by the silver amalgam and the machinable glass ceramic, with no significant difference in cutting efficiencies for aluminum oxide, noble metal alloy, zirconium oxide, and base metal alloy. A
Clinical Significance.—The electric handpieces were run at 200,000 revolutions per minute (rpms) and yet showed significantly greater cutting efficiency than air-turbine handpieces that were run at 340,000 rpms. At equal speeds the electric handpiece may be even more efficient than the air-turbine handpiece for cutting the various materials. Electric handpieces are heavier than the air-turbine type, possibly putting more force on the specimen and producing the increased cutting efficiency.
Choi C, Driscoll CF, Romberg E: Comparison of cutting efficiencies between electric and air-turbine dental handpieces. J Prosthetic Dent 103:101-107, 2010 Reprints available from CF Driscoll, Univ of Maryland Dental School, 666 W Baltimore St, Rm 3-D-08, Baltimore, MD 21201; fax: 410-7063028; e-mail: [email protected]
Dental Materials No more formocresol Background.—The mutagenicity (genotoxicity), carcinogenicity, and toxicity of the formaldehyde product formocresol have been documented in hundreds of articles since the early 1980s, yet its use in full strength by many clinicians worldwide remains. Neither the American Association of Endodontists nor the American Academy of Pediatric Dentistry supports the use of formocresol, but it is still considered widely acceptable for vital pulpotomy or as dressing material. In early 2008 a survey indicated that
186
Dental Abstracts
diluted formocresol was used by 54% of respondents. The problems of formocresol use and acceptable alternatives were outlined. Specific Problems.—Mutagenic and carcinogenic agents such as formaldehyde cause noxious activity on the cell’s genetic makeup and are linked to various types of cancer. Research shows a strong association between formaldehyde and leukemia and nasopharyngeal cancer.
Fig 7.—Clinical picture of left mandible of multiple myeloma patient from Fig 5 showing healthy soft tissues overlying site of previous ONJ. (Courtesy of Williamson RA: Surgical management of bisphosphonate induced osteonecrosis of the jaws. Int J Oral Maxillofac Surg 39:251-255, 2010.)
Clinical Significance.—Support for the surgical management of ONJ unresponsive to conservative measures is growing in the literature. It should be anticipated that some cases will be resistant to all treatment, but the current follow-up duration is insufficient to reveal these.
Fig 5.—Follow-up OPG of patient with multiple myeloma from Fig 4, 1 year after radical debridement, showing the bone in the left mandible and right maxilla has healed with new bone formation. (Courtesy of Williamson RA: Surgical management of bisphosphonate induced osteonecrosis of the jaws. Int J Oral Maxillofac Surg 39:251-255, 2010.)
irregular bony areas, and tension-free primary closure of the wound site under antibiotic coverage preoperatively and after surgery.
Williamson RA: Surgical management of bisphosphonate induced osteonecrosis of the jaws. Int J Oral Maxillofac Surg 39:251-255, 2010 Reprints available from RA Williamson, Dept of Oral Surgery, Faculty of Medicine and Dentistry, Univ of Western Australia, 17 Monash Ave, Perth, WA 6009, Australia; fax: þ61 8 9346 7623; e-mail: [email protected]
Dental Equipment Electric versus air-turbine handpieces Background.—The primary tooth-cutting instrument used in the United States is the high-speed air-turbine handpiece, but electric-motor handpieces are often used in other parts of the world. Seldom are the cutting efficiencies of these two handpiece types compared. The cutting efficiencies of air-turbine and electric-motor
handpieces were evaluated using seven different dental materials. Methods.—Blocks of machinable glass ceramic (Macor), silver amalgam, aluminum oxide, zirconium oxide, high noble metal alloy, noble metal alloy, and base metal
Volume 55
Issue 4
2010
185
significant interaction between material type and handpiece used with respect to cutting efficiency was found (Fig 3). The electric handpiece was more successful than the air-turbine handpiece in cutting high noble metal alloy, silver amalgam, and machinable glass ceramic. No difference in cutting efficiency was found for the other materials.
0.05 Air turbine
Cutting Efficiency
0.04
Electric 0.03 0.02 0.01
y
H
ig
h
no
Al
bl
e
Am al ga m
lo al al et
um um
in
m
id ox
al al et m e
Ba s
M ac or
e
y lo
e id ox um ni
rc o Zi
N
ob le
m et
al al lo y
0
Discussion.—There was a significant difference in the cutting efficiency of the electric and air-turbine handpieces. The different materials also demonstrated significant cutting efficiency differences. The material cut and the handpiece used showed a significant interaction, with the electric handpiece significantly better than the air-turbine handpiece in cutting high noble metal alloy, silver amalgam, and machinable glass ceramic.
Fig 3.—Interaction between handpieces and materials tested. Error bars signify standard deviations. (Courtesy of Choi C, Driscoll CF, Romberg E: Comparison of cutting efficiencies between electric and air-turbine dental handpieces. J Prosthetic Dent 103:101-107, 2010.)
alloy were each cut using a bur 110 times with an electric handpiece and 110 times with an air-turbine handpiece. The weight of the material after the cut was compared with the weight before the cut to determine the weight difference, which was then divided by the duration of the cut (g/s) to yield the cutting efficiency. The results were analyzed statistically. Results.—The electric handpiece proved to be significantly more efficient than the air-turbine handpiece for cutting the various dental materials. The high noble metal alloy was cut most efficiently, followed by the silver amalgam and the machinable glass ceramic, with no significant difference in cutting efficiencies for aluminum oxide, noble metal alloy, zirconium oxide, and base metal alloy. A
Clinical Significance.—The electric handpieces were run at 200,000 revolutions per minute (rpms) and yet showed significantly greater cutting efficiency than air-turbine handpieces that were run at 340,000 rpms. At equal speeds the electric handpiece may be even more efficient than the air-turbine handpiece for cutting the various materials. Electric handpieces are heavier than the air-turbine type, possibly putting more force on the specimen and producing the increased cutting efficiency.
Choi C, Driscoll CF, Romberg E: Comparison of cutting efficiencies between electric and air-turbine dental handpieces. J Prosthetic Dent 103:101-107, 2010 Reprints available from CF Driscoll, Univ of Maryland Dental School, 666 W Baltimore St, Rm 3-D-08, Baltimore, MD 21201; fax: 410-7063028; e-mail: [email protected]
Dental Materials No more formocresol Background.—The mutagenicity (genotoxicity), carcinogenicity, and toxicity of the formaldehyde product formocresol have been documented in hundreds of articles since the early 1980s, yet its use in full strength by many clinicians worldwide remains. Neither the American Association of Endodontists nor the American Academy of Pediatric Dentistry supports the use of formocresol, but it is still considered widely acceptable for vital pulpotomy or as dressing material. In early 2008 a survey indicated that
186
Dental Abstracts
diluted formocresol was used by 54% of respondents. The problems of formocresol use and acceptable alternatives were outlined. Specific Problems.—Mutagenic and carcinogenic agents such as formaldehyde cause noxious activity on the cell’s genetic makeup and are linked to various types of cancer. Research shows a strong association between formaldehyde and leukemia and nasopharyngeal cancer.