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the premium dental site completed 6th successful year of online , entered 7th
year on 23rd Feb 2004
Pre-operation
 Post-operation
 Courtesy: Matthew Brock |
Dental India Newsletter - 6th
June 2004
- ALTERNATIVES IN
POLYMERIZATION CONTRACTION
STRESS MANAGEMENT
- Comments on a lecture
- Treatment of Microbial Infections
I just finished this case. I had
to rely on apex locator & paper point test for length due to the
Zygoma.
For instrumentation I used rotary all
the way and used .02 tapered (at about 350 rpm)for a step-back on MB &
DB, due to the curvature. I used 15-25 in Quantec SC and then 30 and
up in Quantec LX. Apically I had 35 at the apex on MB & DB with
a 45 on the palatal. K3 was used in the .04 and .06 tapers with some
RaCe 35/.08 used coronally.
Matthew Brock - Courtesy ROOTS
(www.dentalindia.com) -
the only professional Indian dental site
Dental India Group - largest group of 11,000 dentists and growing
stronger....
(forward this mail to your colleagues and
friends)
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ALTERNATIVES IN POLYMERIZATIONCONTRACTIONSTRESS MANAGEMENT
1 University of São Paulo, School of Dentistry, Department of Dental Materials, Av. Prof. Lineu Prestes, 2227, São Paulo-SP 05508-900, Brazil; 2 Oregon Health & Science University, School of Dentistry, Division of Biomaterials and Biomechanics, Department of Restorative Dentistry, Portland, OR, USA
Polymerization contraction stress of dental composites is often associated with marginal and interfacial failures of bonded restorations. The magnitude of stress depends on composite composition (filler content and matrix composition) and its ability to flow before gelation, which is related to the cavity configuration and curing characteristics of the composite. This article reviews variations among studies regarding contraction-stress-testing methods and contraction stress values of current composites, and discusses the validity of contraction stress studies in relation to results from microleakage tests. The effects of lower curing rates and alternative curing routines on contraction stress values are also discussed, as well as the use of low-elastic-modulus liners. Moreover, studies with experimental dimethacrylate-based composites and recent developments in low-shrinkage monomers are described.
Key words. Composites, polymerization stress, elastic modulus, shrinkage
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(1) Bone loss in premaxilla occurs in
edentulous area(upper full
plate) when opposed by lower teeth or implanted supported denture on lower in osteoporotic or post-menopausal women. [interesting! not heard this before] (2) you can cantilever from 15 to 18 mm on lower if it opposes upper full plate [why occlusion matters] (3) removes a furcated molar to place an implant, showed an x-ray, could be type I or Type II furcation [extreme....the question to ask, when should you remove a furcated molar?] (4) 8 mm implants are JUST AS EFFECTIVE as 14 mm implants. [This is very important!!! Does this mean the body compensates for short rooted teeth? Does this mean that with bone loss around teeth, the body compensates to make the teeth stronger than you would suspect?] ...David DiBenedetto Treatment of Microbial Infections
This would be an interesting tool in the armamentarium if it's as
effective
an antimicrobial tool as anticipated. I have some doubts. Some clinicians have already been using lasers as antimicrobial tools, some with the addition of photo-adsorbing dyes, some without. My impression is that after the initial enthusiasm for the technique wears off, clinicians find that antimicrobial lasing requires a lot of time compared to other techniques, often with mixed results. The central problem seems to be the narrow focus/power characteristics of lasers. Laser light is powerful enough to kill bacteria, but they typically have very narrow beams. In order to disinfect the entire tooth surface, it's necessary to sweep the beam over the entire tooth surface, much like root planning with light, but without the tactile feedback. Depending on the diameter of the effective kill zone, using a laser to disinfect surfaces can be tedious and if any areas are missed, would they become a recolonizing source? Making the beams wider or more powerful runs the risk of damaging adjacent somatic cells. It's an interesting technical challenge. The research will be interesting. - Bill Landers
From: Stephen Millar Subject: [Periodontal] Treatment of Microbial
Infections FYI, Just received this press release on photodynamic disinfection (PDD) technology for the treatment of microbial infections of the oral cavity. http://www.prnewswire.co.uk/cgi/news/release?id=121701 |