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Antibiotics do
not appear to significantly reduce toothache caused by irreversible
pulpitis. |
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Most frequently visited and
popular pages in Dental India site The opinions and views expressed in this newsletter are not ours and authors have been given due credit | |||||
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Need for
Microscopes
On 2nd March 2007, Carlos Murgel
I have been reading about how good some Rooters are and that they can do endo with out any magnification and I am amazed to think how bad I must be. This is an small example of the sort of things that I can't see even with the lowest magnification of my scope. Tooth # 16 (28 international). Note at the lowest magnifications (images 1,2 and 3) that we can not see the DB canal that emerges at the DP wall of the MB canal. We can only treat what we can see! - Carlos Murgel (Courtesy roots) - More  | |||||
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Mishaps -
Resorption Dental
journals Importance of laternal
canals | |||||
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Closing Mechanics - ESCO
Digest
I use sliding mechanics on 19x25 stainless
steel to close space. In some patients, especially adult
brachycephalic patients, this does not work. What other types of closing
mechanics would you try for these types of cases. In the past I used
19x25 heat teated elgiloy with 4 closing loops.
This was a technique from the Roth
group. But G&H Wire has discontinued that line and I don't fancy
bending the wires myself - Bill Hyman
Dear Dr Hyman, could you try to use 19x25
stainless steel round edge with using acrylic splint in the opposite
dental arch to opening occlusion and making the sliding movement
easier. Hope it helpes - Dr Tsouria-Belaid Nasreddine
Perio products A couple of new products. . . . a purple
Listerine with sodium
fluoride (not quite 0.05 percent that is in Act and Fluorigard. . so I don't know how effective it will be). Another new product is Pronamel toothpaste
by Sensodyne. 5 percent potassium nitrate w/ sodium fluoride (0.15
percent). Might not be a bad choice for adults w/ dentinal
hypersensitivity who are also trying to prevent root caries.
Sunstar Butler has a couple of new
interdental brushes besides the two green go-betweens. One is pink ...
Dr Lynne H. Slim, RDH, MS
What makes periodontal diseases
incurable is not the STM sales pitch, but the definition of
periodontal disease by the experts we are expected to follow. Recession
and bone loss due to periodontal infection and the body's response to that
infection are generally irreversible, so if we define periodontal disease
by those characteristics, of course it's incurable, in the same way that
an amputation is incurable after the affected appendage is discarded. That
is why I said in an earlier post that we should be addressing disease
earlier in the process, but it doesn't mean to me that every person with
loss of bone and gingiva needs to be treated differently than every person
without that loss.
- Howard M Notgarnie, RDH, MA Bob Schulhof - Most often
the bone loss is irreplaceable but if the pocket depths can be reduced to
3mm, andf the periodontal pathogens reduced to below threshhold, then the
patients can maintain themselves with good home care, nutrition and become
like anyone else with normal 6 month hygiene visits. Some other objectives
include lowering CRP & HbA1c to normal levels to minimize the systemic
effects of periodontal disease.. This is the objective of our practices
and why we encourage the taking of before & after data.
This is different than quarterly STM visits that go on forever with no hope of improvement |
Current Imaging Protocol in Dental
Implantology In the March/April 2003 issue of Implant News &
Views, Richard Greenan, explains that pre-surgical radiographic
examination of a proposed implant site is a critical step in the
evaluation of all patients receiving dental implants. Accurate radiographs
not only assist both the surgeon and restorative dentist in projecting the
success of the surgical procedure, but they contribute significantly to
the final clinical outcome. Radiographs displaying optimal clarity and
resolution are essential in all aspects of dental healthcare, but nowhere
is the need for precision greater than in dental
implantology.
A well-taken and properly processed panoramic film
is merely the first step in the screening process with the understanding
that additional views will be required to augment one’s radiographic
assessment. Quality Panoramic radiographs have the following
advantages:
(1) Provide an excellent overall screening tool (2) Help determine the overall quantity of bone present (3) Help determine the relative quality of bone available and (4) Establish the relative location of critical anatomic structures. But unfortunately, the vast majority of panoramic
radio- graphs do not meet diagnostic quality as a screening mechanism nor
are an accurate predictor of available bone, etc. Consistent, diagnostic
panoramic radiographs should be the rule, not the exception! The following
are several inherent limitations in panoramic radiography that we
unfortunately have come to accept:
(1) Extreme sensitivity to errors in patient positioning (2) Inherent horizontal and vertical magnification (varies 20-30%) and (3) Horizontal and vertical height distortion due to errors in patient asymmetries. Mr. Greenan goes on to present several radiographic techniques that will limit distortion, including bisecting angle and using a dowel pin template. Perio systemic
revisted
This is a favorite topic of mine, because I do
believe that there is enough circumstantial evidence for us to be
pro-active with our patients and in our discussions with our patients.
Even though we can not show cause and effect, and may never be able to do
so since we are dealing with diseases with multifactorial etiologies,
every bit of evidence continues to point the way to a connection.
I was reading the latest Grand Rounds in
Oral-Systemic Medicine February 2007 Vol 2 No 1 page 41 guest editorial
"Aetna Dental Weighs in on Oral-Systemic Medicine" What is interesting is
the 4th paragraph which talks about members who had periodontal care
"appeared to have a positive effect on the cost of medical care with
earlier treatment resulting in lower medical costs for members with
diabetes, CAD, and CVD. Members who had periodontal treatment earlier in
the study experienced 9% lower medical costs if they had diabetes, 16%
lower medical costs if they had CAD and 11% lower medical costs if they
cardiovascular disease."
I think this evidence only helps support the view
that we owe it to our patients as healthcare providers to inform them and
to motivate them to eliminate their periodontal disease and maintain oral
and periodontal health. - David | ||||
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April 2005 • Volume 54 • Number 4 Pauli T. Mattila * Hanna Kangasmaa Matti L.E. Knuuttila Sections
Abstract
Introduction Material and methods Results Discussion References Abstract Our previous studies have shown that dietary xylitol supplementation
diminishes bone resorption in rats, as well as protects against
ovariectomy-induced increase of bone resorption during experimental
osteoporosis. Interestingly, ethanol, when given simultaneously with
xylitol, is known to increase blood concentration of xylitol. On the other
hand, ethanol, when given alone, has been shown to increase bone
resorption. The aim of the present study was to evaluate the effects of a
simultaneous dietary administration of 10% xylitol and 10% ethanol on bone
resorption. Bone resorption was determined using measurement of urinary
excretion of hydrogen 3 (3H) radioactivity in 3H-tetracycline prelabeled
rats. Already 4 days after the beginning of dietary supplementations,
excretion of 3H was about 15% lower in the xylitol group (diet
supplemented with 10% xylitol) and about 25% lower in the xylitol-ethanol
group (diet supplemented with 10% xylitol and 10% ethanol) as compared to
the controls. The excretion of 3H in these groups remained smaller than
that of the controls throughout the entire study period of 40 days. The
excretion of 3H in the xylitol-ethanol group remained also smaller than
that of the xylitol group. Bone mineral density and bone mineral content
were determined with a peripheral quantitative computed tomography (pQCT)
system from the rat tibiae at the end of the experiment. Trabecular bone
mineral density and trabecular bone mineral content were significantly
greater in the xylitol group and in the xylitol-ethanol group compared to
the controls. They were also greater in the xylitol-ethanol group as
compared to the xylitol group. Cortical bone mineral density and cortical
bone mineral content did not differ significantly between the groups. In
conclusion, a simultaneous dietary supplementation with 10% xylitol and
10% ethanol seems to diminish bone resorption and to increase trabecular
bone mineral density and trabecular bone mineral content in rats. These
effects seem to be stronger than the effects induced by 10% xylitol
supplementation alone.
Introduction
Xylitol is a 5-carbon polyalcohol that is found in many fruits,
berries, and plants. The richest sources are plums, strawberries,
raspberries, cauliflower, and endives [1]. Xylitol is also an intermediate
of mammalian carbohydrate metabolism. In a human body, 5 to 15 g of
xylitol is formed daily [2].
Our previous experimental studies have shown that dietary xylitol
supplementation diminishes bone resorption in rats [3], as well as
protects against an ovariectomy-induced increase of bone resorption during
experimental osteoporosis [4]. Dietary xylitol also increases the
trabecular bone volume [5] and protects significantly against an
ovariectomy-induced decrease of bone trabecular volume [4].
Interestingly, ethanol, when given simultaneously with xylitol, is
known to increase the blood concentration of xylitol [6]. On the other
hand, ethanol, when given alone, has been shown to increase bone
resorption [7] and to decrease trabecular bone volume [8].
The aim of the present study was to evaluate the effects of a
simultaneous dietary administration of xylitol and ethanol on bone
resorption and bone trabeculation, and to compare these effects with the
effects induced by dietary xylitol alone.
Material and methods
Animals
Thirty 4-week-old male Wistar rats were injected subcutaneously on a weekly basis for 5 weeks with 1 mL of a solution containing 5 μCi/mL of [7-3H(N)]-tetracycline (Du-Pont de Nemours GmbH, Dreieich, Germany) dissolved in distilled water. One week after the last injection, the rats were housed in individual metabolic cages for a 24-hour urine collection that served as a baseline measurement for their hydrogen 3 (3H) excretion. Thereafter, the rats were divided randomly into 3 groups of 10. Animals in the control group were fed a basal powder diet, Lactamin R3 (Labfor, Stockholm, Sweden), consisting of barley meal 28%, wheat meal 20%, wheat germ 20%, wheat middlings 10%, soya meal 7%, fish meal 7%, fodder yeast 3%, minerals 3%, vitamins and trace elements 1%, and fat 1%. This diet contains 1.1% calcium, 0.8% phosphorus, and 600 IU/kg vitamin D3. The rats had free access to tap water. Animals in the first study group (the xylitol group) were fed the same diet supplemented with 10% xylitol (Cultor, Espoo, Finland). Animals in the second study group (the xylitol-ethanol group) were fed the same diet as the xylitol group, but their tap water was supplemented with 10% ethanol. The rats were housed in a temperature- and light-controlled room (21°C, 12-hour light-dark cycle). Their urine was collected about twice a week for 40 days. They were weighed weekly, and their food and liquid intake was measured. After the urine collection period, the rats were killed with an overdose of ether followed by decapitation. Their left tibiae were prepared for bone analyses. The study protocol was approved by the Ethical Committee on Animal Experiments of the University of Oulu, Oulu, Finland. The experimental procedures complied with the Guiding Principles in the Care and Use of Animals, approved by the Council of the American Physiological Society in 1991. Measurement of 3H radioactivity
The volume of urine excreted was measured and the amount of
3H-radioactivity present in a 1-mL aliquot was determined with a
scintillation counter 1215 Rachbeta II (Wallac, Turku, Finland) using
Hydrofluor (Pational Diagnostics, Manville, NJ) as the liquid
scintillation counting solution. The total excretion of 3H was calculated
as an indicator of the amount of resorbed bone mineral, as described by
Klein and Jackman [9]. The continuous monitoring method was that described
by Mühlbauer and Fleisch [10].
Peripheral quantitative computed tomography measurements
The left tibiae of the rats were scanned with a peripheral
quantitative computed tomography (pQCT) system, the Stratec XCT 960A
(Norland Stratec Medizintechnik GmbH, Birkenfeld, Germany), using a voxel
size of 0.148 × 0.148 × 1.25 mm3. The diaphysis was scanned at midshaft.
The distal metaphysis was scanned adjusting the scan line to 5 mm proximal
to the distal end of the tibia using the scout view property of the pQCT
software. Cortical bone mineral density and cortical bone mineral content
were determined from the scans of the tibial diaphysis. The tibial distal
metaphysis scans were used for the determinations of trabecular bone
mineral density and trabecular bone mineral content. The concentrical
peeling method (peel mode 1) with a 45% inner region corresponding to a
pure trabecular area was used, as described by Tuukkanen et al [11].
Statistical analysis
Information from a series of urinary measurements on each individual
rat was summarized as the area under the curve, as described by Altman
[12]. The statistical significance of the differences between the groups
concerning all measured variables were calculated by analysis of variance
(ANOVA), further comparison being made using Fisher's protected least
significant difference (PLSD). The statistical computer program used was
Stat View II for Macintosh (Abacus Concepts, Berkeley, Calif).
Results The weight gains of the rats did not differ significantly between the
groups (data not shown) indicating no major differences in the growth of
the animals. The average diet and liquid intakes were also similar in the
groups (data not shown) indicating that the dietary supplementations did
not change the dietary habits of the rats. There was some difference in
urine volume outputs between the groups (data not shown). However, the
possible confusing effect caused by different urine volumes was eliminated
by calculating the amount of 3H radioactivity in proportion to the whole
daily volume of urine.
The amounts of urinary 3H excreted during the experimental period are
seen in Fig. 1. A reduction of the excreted radioactivity was observed in
every group because of the decreasing amount of 3H in bone. Already in the
first measurement, 4 days after the beginning of dietary supplementations,
the excretion of 3H was about 15% lower in the xylitol group and 25% lower
in the xylitol-ethanol group, as compared to the controls. The excretion
of 3H in both the xylitol and xylitol-ethanol group remained smaller than
that of the control group throughout the entire study period of 40 days.
When calculating excretions of 3H during the whole experimental period,
the xylitol (P < .002) and the xylitol-ethanol (P < .001) groups
differed significantly from the control group. The excretion of 3H in the
xylitol-ethanol group was also significantly smaller than that of the
xylitol group (P = .02).
Fig. 1. Urinary 3H excretions of the rats during the experimental
period. Values are presented as mean ± standard error of mean; n = 10 per
group. Between groups, comparison was measured as the area under the
curve. Statistical differences were calculated by the ANOVA, further
comparison being made using Fisher's PLSD. Significant differences:
control group vs xylitol group (XYL), P < .002; control group vs
xylitol-ethanol group (XYL-ETH), P < .001; xylitol group vs
xylitol-ethanol group, P = .02.
The results of the pQCT analyses are seen in Table 1. The trabecular
bone mineral density at the end of the experimental period was
significantly greater in the xylitol group (P < .01) and in the
xylitol-ethanol group (P < .01) compared to the control rats. The
xylitol-ethanol group differed also significantly from the xylitol group
(P < .05). Accordingly, trabecular bone mineral content was
significantly greater in the xylitol (P < .01) and xylitol-ethanol (P
< .01) groups compared to the controls. The xylitol-ethanol group
differed significantly also from the xylitol group (P < .05). Cortical
bone mineral density and cortical bone mineral content did not differ
significantly between the groups.
-------------------------------------------------------------------------------- Table 1. Results of the pQCT analyses -------------------------------------------------------------------------------- Control rats Rats with 10% dietary xylitol supplementation Rats with 10% dietary xylitol and 10% ethanol supplementation (a) (b) (c) Tibial metaphysis Trabecular bone mineral density (mg/cm3) 189.3 ± 23.1 254.5 ± 46.6 303.5 ± 73.1 Trabecular bone mineral content (mg/cm) 1.65 ± 0.20 2.02 ± 0.26 2.28 ± 0.35 Tibial diaphysis Cortical bone mineral density (mg/cm3) 1323.0 ± 16.1 1323.6 ± 10.3 1318.3 ± 6.8 Cortical bone mineral content (mg/cm) 7.89 ± 0.54 7.88 ± 0.44 7.70 ± 0.55 All values are expressed as mean ± SD; n = 10 per group. Statistical differences were calculated by the ANOVA, further comparison being made using Fisher's PLSD. Significant differences in trabecular bone mineral density: a vs b, and a vs c, P < .01; b vs c, P < .05. Significant differences in trabecular bone mineral content: a vs b, and a vs c, P < .01; b vs c, P < .05. -------------------------------------------------------------------------------- Discussion
Several studies have confirmed that the urinary excretion of 3H
radioactivity in 3H-tetracycline prelabeled rats is a valid marker of bone
resorption [9,10]. Multiple prelabeling of rapidly growing rats permits
homogenous distribution of 3H-tetracycline throughout the bones [9], and
the elimination of 3H directly reflects bone resorption [13]. This is
possible because tetracycline incorporated to the bone is removed only
during resorption [14], and because very little of the removed
tetracycline is reused at new sites of bone formation [15].
Dietary xylitol supplementation in rats induced a significant and
rapid reduction of bone resorption that was maintained over the whole
experimental period of 40 days. This is well in accordance with our
previous findings [3]. A simultaneous ethanol supplementation seemed to
further strengthen the xylitol-induced reduction of bone resorption. This
is quite interesting, because ethanol, when given alone, has been shown to
increase bone resorption [7]. On the other hand, ethanol, when given
simultaneously with xylitol, is known to increase the blood concentration
of xylitol [6].
Dietary xylitol supplementation also induced a significant increase
in the trabecular bone mineral density and in the trabecular bone mineral
content of the distal metaphysis of tibia. This is in accordance with our
previous findings [5], as well as with the diminished bone resorption
detected in the present study. Accordingly, with the bone resorption
findings, ethanol, when given simultaneously with xylitol, seemed to
induce an even greater increase in the values of the trabecular bone
markers compared to the supplementation of the diet with xylitol alone.
Interestingly again, ethanol, when given alone, has been shown to decrease
the trabecular bone volume [8]. The cortical bone mineral density and the
cortical bone mineral content did not differ significantly between the
groups. This may indicate that trabecular bone is more sensitive than
cortical bone to these kinds of effects induced by xylitol. On the other
hand, the experimental period in the present study was quite short, about
1 month, and possible changes in the cortical bone may need a longer time
to become detectable.
Although ethanol, when given alone, has been shown to increase bone
resorption and decrease bone trabeculation, it can be said that a
simultaneous dietary xylitol administration is most probably very
effective in protecting against such ethanol-induced changes.
In conclusion, a simultaneous dietary supplementation with 10%
xylitol and 10% ethanol seems to diminish bone resorption and increase
trabecular bone mineral density and trabecular bone mineral content in
rats. These effects seem to be stronger than the effects induced by 10%
xylitol supplementation
alone. | |||||
