- I Number- X I April 2007
In this Issue:
Laughter - The best Medicine
Research ties gum disease to a
host other major medical conditions
Breakthrough technology to hit
the detection of Dental Caries
Evaluation of the efficacy
of a collagen GBR membrane (BioMend Extend) supported by autogenous bone
grafts, for the treatment of peri-implant bony
defects, during implant placement."Part III- Dr.Yousef Abd ElGhaffar
Laser Dentistry - How you can
bring the children more happy to visit the dentist? - Dr.Maziar Mir
Dear Fellow Dentist,
We are happy to bring the new edition of Dental Follicle .Yahoo groups
has pretty active ! A lot of questions and a lot of answers!I thought
why not incorporate the best answer in the Dental Follicle!
When the discussion on "Enamel Microabrasion" came up one good doctor
"Dr.Ramesh Kanna" from India posted a small paragraph on the "method
of doing Enamel Microabrasion"
Enamel Micro abrasion i use Opallusture from Ultradent, its 6.6% HCL,
we have to select only mild to moderate flourosis cases, clean and
polish them with shade matching ( Routine) then apply Opalluture on
the enamel surface of the tooth to be microabraded ( entire labial
surface) , and we get microabrading brushes with the kit, so we have
to use them on the Enamel surface in a round polishing motion as in
tooth prophylaxis after scaling , with a little bit of firm
pressure. use it for 60 sec to 90 sec and with a pause if you want
use again. clean and observe, if not satisfied you can repeat for 2
- 3 times, be aware of sensitivity. after microabrasion you can ask
the patient to use flouride gel and continue home bleaching for
more whiter teeth.
macroabrasion its the same procedure, only difference is, its used
for moderate to above moderate flourosis cases, in which the Enamel
surface of the tooth/teeth to be treated is roughened slightly by
using Fine diamond bur( yellow ), then the procedure is as same as
A young Dentist had just started his own Clinic. He rented a beautiful
office and had it furnished with antiques. Sitting there, he saw a man come
into the front office. Wishing to appear the "busy dentist", the gentleman
picked up the phone and started to pretend he had to give an appointment.
Finally he hung up and asked the visitor, "Can I help you?"
The man said, "Yeah, I've come to activate your phone lines."
ties gum disease to a host other major medical conditions
"Research compiled over
the last five years suggests that gum disease — especially if the condition
has persisted for a long time without treatment — can contribute to
diabetes, cardiovascular disease and stroke, pregnancy complications, and
perhaps even Alzheimer's disease, osteoporosis and some types of cancers,"
the paper says. "Infections in the mouth also may increase the risk to
people undergoing several types of surgery, including transplantation and
cardiac valve replacement."
recently as last month, a study published in the New England Journal
of Medicine found that treating severe gum disease can improve the
function of blood vessel walls, improving heart health. And in this
month's Journal of Periodontology, two studies found periodontal
bacteria (bugs normally found in inflamed gums) in the arteries of
people with heart disease and in the placentas of pregnant women with
high blood pressure.
technology to hit the detection of Dental Caries
Neks Technologies Inc,
announced that the Food and Drug Administration (FDA) has approved the D-Carie™
mini caries detection device as an aid in the diagnosis of interproximal
The D-Carie mini is a
lightweight, easy-to-use, cordless device that can be used as an aid for
clinicians to quickly locate and diagnose caries. The D-Carie mini uses
Light Emitting Diode (LED) and fiber optic technologies to accurately detect
both occlusal and interproximal caries. The device requires no calibration
and is easy to sterilize. The D-Carie mini is not a laser, and therefore can
also be operated by hygienists.
When used as a
diagnostic aid in conjunction with an X-ray, the neks D-Carie mini allows
dentists to assess a third dimension - the volume of caries - prior to
opening the tooth. The device also provides dentists with an option for
examining and diagnosing children, pregnant women and patients who prefer to
forgo X-rays or limit their exposure to them for health or personal reasons.
For more information on the D-Carie mini and the DetecTar mini, clinicians
can register online and participate in an archived Web Seminar entitled
"Introduction to the Art of Detection" at
http://www.neks.ca/web_seminars_en_edit.htm For a detailed product
demonstration on the D-Carie mini, an online video is available at:
Evaluation of the efficacy of a
collagen GBR membrane (BioMend Extend) supported by autogenous bone
grafts, for the treatment of peri-implant bony defects, during implant
Besides having the same
criteria of a non-resorbable barrier, special demands must be added to a
resorbable barrier because of the bioresorption process. To some extent, the
bioresorption process will always be associated with a cellular response
from the surrounding tissue, irrespective of whether the material has been
degraded by enzymatic activities or has been hydrolyzed. Since this process
entails some inflammatory response, the subsequent inflammation should be
minimal, reversible, and not interfere with regeneration. Moreover, the
bioresorption process must be controlled so that membrane is maintained for
a sufficient length of time to perform its function for tissue guidance
during the initial healing period (Gottlow 1998).
Ideally, a bioabsorbable material should be safe, cost effective, easy to
use, remain in place until regeneration has occurred, and not to interfere
with newly formed tissue. Furthermore, they should be limited to areas with
minimal gingival recession and sufficient width and thickness of keratinized
gingiva, where primary closure is sure to be achieved (Becker et al., 1996).
Bioresorbable barrier membranes used for GBR include collagen, oxidized
cellulose and polylactic-polyglycolic acid co-polymers.
A study was carried out to evaluate the efficacy of polylactic acid and
polyglycolic acid (PLA/PGA) resorbable membranes in conjunction with
autogenous bone grafts when used for the treatment of implant dehiscences
and/or fenestrations versus (e-PTFE) non-resorbable membranes. A slightly
higher percentage of bone fill was found in the e-PTFE group (98.20%) than
in the PLA/PGA group (88.56%), but the difference was not statistically
significant (Simion et al. 1997).
Hurzeler et al. 1997 performed a study on GBR around dental implants placed
in atrophic alveolar ridges using an experimental, nonporous bioresorbable
barrier made of poly D, L-lactid-co-trimethylencarbonate and non-resorbable
(e-PTFE) membranes were used as a control group. The mean direct mineralized
bone-to-implant contact length fraction was 32% of the total implant length
in the test sites and 58% in the control sites. Control sites exhibited
significantly greater bone fill compared to the experimental sites.
Histologic observations of test specimens demonstrated a moderate
inflammatory reaction related to the degradation and resorption products of
Synthetic bio-resorbable membrane barriers were claimed to cause clinical
problems. Infections and inflammatory reactions were observed around
breakdown debris of Guidor membrane barriers (polylactic acid type) (Schmitz
et al. 2000).
Among the bioabsorbable materials, collagen which is the most important
structural protein component of the body, naturally bioabsorbable, with
proven medical applications, the use of collagen as a biomaterial has been
advocated based on several factors such as its favorable role in cellular
development, wound healing, and blood coagulation (Zahedi et al. 1998).
Because collagen is the most abundant protein in the body the search for a
biodegradable material has lead to the development of collagen membranes,
which have been used in medical fields for decades (Chen et al. 1995).
It had been reported that there is a similarity between collagen in human
skin and certain animal tissues. Since human body enzymes can degrade animal
collagen, so animal collagen is attractive as a GBR barrier material.
Collagen membranes currently available are of various subtypes, but usually
fabricated with type I collagen derived from various bovine, porcine or
equine animal sources and harvested from tendon or dermis (Tripletti et al.
Collagen barriers are manufactured using extrusion-coagulation and air
drying which forms sheets of material from dilute collagen solutions. The
collagen is dissociated, purified and reconstituted before final sheet
forming to reduce the potential for antigenic response when the material is
implanted. Most collagen barriers are cross-linked to increase their
strength, extend their resorption time and reduce their potential
antigenicity (Wang et al. 1998).
Collagen is bioresorbable. During enzymatic degradation it will incorporate
with the flap to support the new connective tissue attachment. This may
result in augmenting tissue /flap thickness to further protect underlying
bone formation and prevent future bone loss. Unlike some acid-based
resorbable membrane materials, it does not release acid byproducts into the
wound areas as the material breaks down (Pitaru et al. 1989).
In order to evaluate the biocompatibility and resorption pattern of a human
collagen graft material in both in vitro and in vivo, human collagen
extracted from placenta was implanted subcutaneously in 10 Sprague Dawley
rats. The graft was encapsulated by day 7 and was slowly resorbed over 56
days with minimal inflammatory response (Quteish et al. 1991).
Ideal barrier membrane should stay in place for at least 4 to 6 weeks before
being surgically removed, so the bioresorbable membranes as collagen barrier
membrane should not degrade before a sufficient time to enhance
regeneration. Many steps have been taken to delay its degradation process.
This could be achieved either by increasing their structural integrity by
cross-linking or by delaying the degradation process using metalloproteinase
inhibitors which inhibit metalloproteinases responsible for degradation.
Various cross-linking techniques have been developed. These include
ultraviolet light (Pitrau et al. 1988), hexamethylene diisocyanate (HMDIC) (Minabe
et al. 1989 and Kodma et al. 1989), glutaraldehyde plus irradiation (Quteish
et al. 1992), and diphenylphosphorylazide (DPPA) (Brunel et al. 1996 and
Zahedi et al. 1998). The glutaraldehyde technique was reported to leave
cytotoxic residue during the process and to overcome the drawback of this
technique, the diphenylphosphorylazide (DPPA) technique was developed.
The use of collagen membranes has not yet been approved by the United States
Food and Drug Administration (FDA) for treatment of dehiscences associated
with implants due to lack of researches concerning this matter (Wang and
Some animal studies were carried out to evaluate the efficacy of collagen
barrier membranes in GBR. In a pilot study, Colangelo et al. 1993, created
through and through defects on the lateral aspect of rabbit mandibles and
then treated them with either a cross-liked bovine tendon type І collagen
membrane or no-treatment control. The histologic evaluation at 30 days
demonstrated a nearly complete continuous layer of lamellar bone with
osteoblastic activity in the collagen membrane-treated group compared to
only fibrous connective tissue in the control group.
Another study was carried out in 1993 by Sevor et al. Buccal dehiscences
were surgically induced in dog mandibles. Implants were then placed in a
random pattern in both sides of the mandibles (two of each type of implant
in each side of the mandible). A resorbable collagen barrier membrane (CollaTec)
was placed around one pair of implants on each side. The other two implants
on each side served as controls. The sites were examined clinically and
histologically after 4 or 8 weeks to assess bone regeneration. At 4 weeks,
the mean defect fill was 69.16% in the collagen membrane-treated group
compared to 24.07% in the control group. At 8 weeks, the mean defect fill
was 80.29% in the collagen membrane-treated group compared to 38.62% in the
control group. The author also reported excellent wound healing at
experimental sites in contrast to results with other materials. He suggested
that as collagen products have been extensively utilized to heal burns and
to dress surgical wounds, collagen has been found to be a chemoattractant
for fibroblasts and connective tissue elements. Examination of certain
histologic sections in the present study showed that bone and bone elements
proliferated in close approximation to the collagen membranes.
Zahedi et al. 1998 performed a study to evaluate the potential of Calfskin
origin collagen membrane (Paroguide) in the healing of mandibular bone
defects. The experiment was carried out on 25 Wistar rats. After exposing
the mandibular ramus bilaterally, 5 mm diameter full-thickness circular bone
defects were surgically created. Defect on one side was covered by the
membrane (experimental), the defect on the other side was left uncovered
(control) before closure of the overlying soft tissues. In the 90 and 180
day animals, all experimental defects were completely closed. While in
control defects, no statistically significant increase in bone regeneration
Francisco et al. 2000 have clinically evaluated an absorbable a porcine
dermis origin collagen membrane (Bio-Gide) and a non resorbable (PTFE)
membrane, associated with or without deproteinized bovine bone mineral
xenografts (BioOss), for the treatment of ligature-induced peri-implantitis
defects in dogs. The results showed percentage vertical bone fill with use
of the resorbable membrane alone (21.78±16.19) and with the use of
resorbable membrane together with BioOss (27.77±14.07). With use of non-resorbable
membrane the percentage of vertical bone fill was (18.86±10.63) and with use
of non-resorbable membrane togther with BioOss it was (19.57±13.36).
However, he concluded that no significant statistical difference was
detected among treatments.
A comparative analysis between two different collagen membranes to treat
peri-implant buccal dehiscence defects in eight mongrel dogs was performed.
The study compared Bio-Gide to BioMend Extend (Bovine tendon origin)
collagen barriers, also the study included control sites which were left
without barrier. Clinical reentry was carried out after 4 weeks and after 16
weeks. After 4 weeks the defect height was 3.08±0.10 mm in BioGide barrier
group, 3.28±0.11 mm in BioMernd Extend barrier group, and 3.41±0.12 mm in
control group. After 16 weeks the defect height was 3.29±0.12 mm in BioGide
barrier group, 3.11±0.11 mm in BioMernd Extend barrier group, and 3.091±0.15
mm in control group. The sites treated with barriers showed higher
percentage of bone fill and bone-to-implant contact, however, sites treated
with BioMend Extend demonstrated significantly greater bone-to-implant
contact than sites treated with Bio-Gide barriers (Oh et al. 2003).
Few clinical studies were carried out to evaluate the efficacy of collagen
barriers for treating dehiscence defects around dental implants. Zitzmann et
al. 1997 studied GBR using Bio-Gide collagen membrane versus (e-PTFE) for
treating 84 exposed implant surfaces, both were supported with BioOss. Bone
fill was achieved for the collagen membrane group was 92% against 78% bone
fill for the (e-PTFE) membrane group. In the latter group, 44 % wound
dehiscences and/or premature membrane removal occurred.
Paroguide collagen membrane was evaluated for GBR to treat patients with
insufficient ridge width (less than 5 mm). The membranes were supported by
collagen sponges to maintain the space buccally and lingually. The defects
which demonstrated sufficient width for implant placement were 75%. Mean
increase in the size of the crest was 2.5 mm (3 to 5.5 mm) (Parodi et al.
Another study was performed by Nemcovsky et al. 2000, where buccal
dehiscence defects were treated with GBR procedures using resorbable Bio-Gide
collagen membrane supported by bovine bone mineral after the placement of 28
implants in 21 patients. Mean defect area at the time of implant placement
was 23.7 mm². Implants were uncovered 6 to 8 weeks later. The mean defect
area at the time of uncovering was 0.7mm². The mean percentage of defect
reduction (clinical bone fills) was 97%.
Carpio et al. 2000 compared the efficacy of a porcine-derived bioresorbable
Bio-Gide collagen membrane versus an (e-PTFE) membrane for GBR using a
bovine bone xenograft/autograft composite in defects surrounding dental
implants. Defect size was recorded at stage 1 and 2 surgeries (performed 6
months apart). At baseline, the defect height in the group treated with
collagen barriers had a mean of 4.63±0.49 mm and the defects width had a
mean of 3.36±0.28 mm. The defects height in the group treated with (e-PTFE)
barriers had a mean of 4.18±0.39 mm and the defects width had a mean of
4.36±0.40. After 6 months reduction in defect height was 2.65±0.61 mm and
reduction in defect width was 1.95±0.60 in group treated with collagen
barriers. The reduction in defects height was 2.26±0.61 mm and reduction in
defects width was 2.65±0.56 in group treated with (e-PTFE) barriers.
Hämmerle and Lang 2001 carried out a study to evaluate efficacy of Bio-Gide
collagen membrane supported by BioOss for GBR to treat buccal dehiscence
defects around dental implants. The study included 10 patients. At baseline,
the deepest extensions of the defects were located at the buccal aspects
(mean 7.8 mm, SD 1.9 mm). At re-entry, the mean defect had decreased to 2.5
mm (SD 0.6 mm). This difference was statistically significant (P < 0.01).
Initially, in 62% of sites the depth ranged from 0-3 mm, in 23% it ranged
from 2-4 mm, and in 15% it amounted to more than 6 mm. Six to 7 months
later, at re-entry, 95% of sites were 3 mm and less in depth and 5% ranged
from 4-6 mm. Defect resolution, as assessed by the amount of coverage of the
initially exposed rough implant surface reached a mean value of 86% (SD
33%). One hundred percent resolution was accomplished at 8 out of 10
implants, 60% at one and 0% at another implant.
Brunel et al. 2001 performed 7-year follow up for GBR prior to implant
placement using Paroguide collagen membranes supported by hydroxyapatite
(HA) crystals. The results showed bone filling at a treated sites and
osseointegration rate of 86% after 7-year observation period. He concluded
that these results confirm the possibility of regenerating bone by means of
bioresorbable membranes, assuring at the same time the long-term success for
implants inserted in regenerated sites.
Tawil et al. 2001 evaluated the efficacy of a bioresorbable collagen
membrane (Bio-Gide) in combination with autogenous bone graft in the
treatment of peri-implant dehiscences, fenestrations, or limited vertical
defects. Autogenous bone was used in all cases to fill the defect and
maintain the space underneath the barrier. The membrane absorbed the blood
and easily covered and adhered to the underlying bone. It was not stabilized
by any retentive means. Sixteen to 32 months postoperatively, the sites were
re-entered and the amount of bone regenerated was measured. The mean defect
height and width respectively were 5.28mm and 3.11mm at the time of the
first surgery. At the time of second surgery the mean defect height and
width respectively were 0.61 mm and 0.94 mm. The results showed significant
bone gain (average 87.6%) in the treatment of peri-implant bony defects with
Bio-Gide and autogenous bone.
Regarding the quality of bone gained through GBR by the use of collagen
barriers, it was proved that collagen barriers provided qualitative bone
regeneration comparable to the standard (e-PTFE) material as assessed by
histological examination (Friedmann et al. 2002).
Zahran and Al-Shirbiny 2003 studied the efficacy of a bioabsorbable collagen
membrane (BioMend Extend) in combination with decalcified freeze-dried bone
allograft (DFDBA) in the treatment of peri-implant dehiscence defects. Ten
patients having twelve endosseous implants with buccal dehiscence defects
were included in the study. Surgical re-entry was carried out 6 to 9 months
post surgically, in conjunction with abutment connection. The initial height
of the dehiscence defects ranged from 3 to 6 mm with an average of 3.95 mm.
On re-entry, the height of the residual defects varied between 0 to 1.5 mm
with a mean value of 0.66 mm with an average of 84.76% ±11.81% of defect
fill. Four defects out of 12 showed 100% vertical bone gain. The initial
width of the dehiscence defects ranged from 2 to 3 mm with an average of
2.33 mm. The residual width of defects varied between 0.0 to 1.00 mm with a
mean value of 0.08 mm.
- How you can bring the children more happy to visit the
DDS, MSc, PhD
Assistant Prof. ZPP,
RWTH Hospital, Aachen, Germany
We learned a lot to
control the behavior of our child and adolescent patients during our
studies. In experience a lot of dentists just refer the Children to
Paedodontists while do not like to spend a lot of time for making the
patient co-operative.As a dentist, who loved to be able to have a young boy
or girl happy on the dental chair, I have been trying to prepare the tooth
cavities just by the help of Lidocaine gel or soray and hand instruments.
With hatchet of chisel, a lot of dentists just remove the soft caries and
use Glass Ionomers to fill such a cavity in a primary tooth whcih maybe is
going to be replaced with a permanent tooth in some years. But most of such
a filled cavities will show the recurrence and poor child will come back to
the dentist with pain after a year or less. So, pulpotomy as a secondary
health providing level of treatment will not be possible to be done painless
even with hand instruments!
Last year, the dean of our
school asked me to start some clinical studies with primary teeth and
provide my peadiatric dentistry service with the assistance of Er:YAg and
Nd:YAG lasers. So, we started to do pulpotomies and following the methods
that were earlier introduced by Gutknecht et al. did the procedures in this
1- Local anesthesia
2- Isolation with rubber
3- Sterile deep caries
removal and pulp chamber exposure following by removing the roof of pulp
chamber with Er:YAG laser (400 mJ, 10-15 Hz).
4- Surgical removal of
coronal pulp with excavators or sharp Black’s spoons.
5- Coagulation and
fixation of root canal orifices with Nd:YAG (2 W, 20 Hz, 10 Sec, 2-3 mm
distance from the orifice).
6- Placement of capping
material (Ca(OH)2 plus Iodoform)
7- Final filling (
Phosphate cement following by SSC)
The local anesthesia here
is also as first step, but there was no need to any additionnal injection
during the procedures as is routine while just preparing the cavity and
removing the pulp soft tissue with rotary instruments. The same procedure is
possible to be done with Diode lasers instead of Nd:YAG as well. Also, the
Co2 lasers are in trial in our clinics to see the advantages and
disadvantages in next 4 years. In current studies reported by Hugo et al on
2006 the success rate of the mentioned protocol, is reported as 62 out of 65
(95.38%). Wilder-Smith and her research group have shown also in another
study that CO2 laser (Duolase™), emitting at 9.3 mm, used in the Superpulse,
noncontact mode (macropulse duration:300 ms, spot size: 250 mm, average
energy: 3.5 W, peak energy: 20 W, pulse repetition rate: ~500 Hz) results in
hemostasis when irradiated to exposed pulps with the exposure of up to 5 mm.
In this study also they reported significant better clinical and
radiographic results comparing the routine methods. According to the animal
and clinical studies that are done, these procedures could be used
successfully for pulpotomy, but there is no report to show if Er:YAG with
the pulse durations of more than 500 us could have the same or even better
effects. This wave length has received the FDA clearance for pulpotomy on
2002, but there is no detail about the most efficient pulse length. We are
working strongly on this topic and would be happy if the investigators or
clinicians who have a similar reaserch or clinical experience work keep in
touch with our group via email: email@example.com
Also, all the literature
of this suggested applications of lasers in pedodontics are available and
will be sent in request.