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Collagen

Accelerated Degradation of Collagen Membranes

Accelerated Degradation of Collagen Membranes in Diabetic Rats is Associated with Increased Infiltration of Macrophages and Blood Vessels

Objectives Increased collagenolytic activity in diabetes may
compromise collagen membrane (CM) survival. Tetracycline
(TTC) possesses anti-collagenolytic properties and delaysCM
degradation. This study evaluated macrophage and capillary
infiltration within CMs in diabetic rats.
Materials and methods Diabetes was induced in 20 Wistar
rats by streptozotocin and 20 served as controls. Biotinlabeled
CM discs were immersed in either TTC (50 mg/ml)
or PBS. In each animal, 2 discs (TTC and control) were implanted
under the parietal periosteum and rats were sacrificed
at 2 or 4 weeks post-implantation. The area and thickness of
the residual disc collagen were measured following staining
with streptavidin, and the number of macrophages and blood
vessels within the membranes was determined using specific
antibodies (to CD68 and transglutaminase II, respectively).
Results Diabetes significantly reduced the area and thickness
of the CMs, while TTC increased CMthickness significantly
in both groups of rats at 2 and 4 weeks. Diabetes
increased the number of macrophages (∼eightfold at
2 weeks and ∼fourfold at 4 weeks), but TTC had no significant
effect. Finally, diabetes increased the number of blood
vessels within the discs (∼threefold at 2 weeks and ∼twofold
at 4 weeks), while TTC had no effect.
Conclusions Diabetes increases degradation of native CMs
and the number of blood vessels and macrophages within
them. TTC immersion delays CM degradation without an apparent
effect on macrophage and blood vessel penetration.
Clinical relevance Enhanced CMdegradation in diabetic conditions
which impair guided regenerative procedure outcome
is apparently related to increased blood vessel formation and
macrophage infiltration.

Hyaluronic Acid Slows Down Collagen Membrane

Hyaluronic Acid Slows Down Collagen Membrane Degradation In Uncontrolled Diabetic Rats

Abstract
Aim: To examine the in vitro biokinetics of hyaluronic acid (HA) from a collagen membrane
(CM) and to evaluate the in vivo effect of immersion of the CM in HA solution
on its degradation in streptozotocin (STZ)‐induced diabetes conditions in a rat calvaria
subcutaneous model.
Background: CM degradation is accelerated in uncontrolled diabetic rats. Immersion
of CM in HA has been suggested to decrease their resorption rate without interfering
with their tissue integration and structural degradation. However, it is unknown
to what extent CM degradation may be influenced by its immersion in HA solution
under a condition mimicking a medically compromised situation with an increased
inflammatory level such as diabetes.
Materials and Methods: CMs were soaked in cross‐linked HA. Protein adsorption and
the HA release were quantified by ELISA. Diabetes was induced in sixteen rats, while
16 healthy rats served as control. CM was prepared and labeled prior to implantation
with Biotin. Seventeen CM were immersed in HA and 17 CM in PBS. In each animal,
one test or one control disk was implanted. In order to compare the collagen content,
two similar non‐implanted CM were used as baseline. Fourteen days after surgery,
thirty‐two animals were sacrificed. The entire calvaria including the skin above, was
chemically fixed, decalcified, and embedded in paraffin. Five‐μm‐thick sections were
analyzed histologically and histomorphometrically using H&E and avidin‐peroxidase
staining.
Results: The in vitro results demonstrated that the CM adsorbed roughly 80% of
the total HA content. After 10 days, 36.3% of the initial HA remained on the CM.
The in vivo results demonstrated that diabetes significantly reduced the thickness of
the CM, while HA had a significant effect on keeping the membrane thickness. HA
increased the residual collagen content in the diabetic group (P < 0.0001) but no such effect was observed in the healthy group. Conclusion: Immersion of CM in HA prior to the implantation delays membrane degradation in uncontrolled diabetic compared with normoglycemic rats.

Opposting Effects of Diabetes

Opposing Effects of Diabetes and Tetracycline on the Degradation of Collagen Membranes in Rats

Background: Increased collagenolytic activity, characteristic
of uncontrolled diabetes, may compromise collagen
membrane (CM) survival. Tetracycline (TCN) possesses
anticollagenolytic properties and delays CM degradation in
healthy animals. This study evaluates the degradation of
TCN–immersed and -non-immersed CMs in rats with diabetes
compared to those with normoglycemia.

Explantation of Failed Implant & GBR

Explantation of Failed Implant and GBR

Dental implants are successfully used to replace the missing teeth. Despite the predictability of success of dental implants. Dental implants have a high success rate, but some people experience dental implant failure. It’s estimated that about 5 to 10 percent of dental implants fail, either shortly after a procedure or months or years later.

Extraction of Lost Tooth, While Saving Adjacent Implant

Extraction of Lost Tooth While Saving Adjacent Implant

The article introduces how to prepare surrounding area of an implant after extraction of a lost tooth.   The article includes before pictures and X-Rays, results after 10 days of healing and a video of the surgery. An 80 year old male patient was referred to me by his prosthodontist.  They wanted the lost tooth extracted, […]

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