ATRISORB® GTR Barrier is indicated for the surgical treatment of periodontal defects to aid in the regeneration and integration of tissue components in guided tissue regeneration procedures. ATRISORB® GTR Barrier is not intended for use in defects outside the indications statement.

Device Description

The ATRISORB® polymer formulation is a sterile, synthetic flowable polymeric formulation which is bioabsorbable and has been developed for GTR procedures by Atrix Laboratories, Inc. It consists of a polymer of lactic acid, poly(DL-lactide) (PLA), dissolved in N-methyl-2-pyrrolidone (NMP). The finished device is provided in two different packaging configurations: the ATRISORB® GTR Barrier Kit (case kit) and the ATRISORB® GTR Barrier multipack (multipack). The case kit contains the polymer formulation, a barrier forming case with porous pads and spacers, sodium chloride solution, and instructions for use. The multipack contains three dose packs of the polymer formulation, three 18 gauge cannulae, and instructions for use. The barrier functions by isolating the surgical site to facilitate regeneration. It can be preformed using the case or applied directly in situ. The formed barrier is a film that solidifies and bioabsorbs over several months.

AI/ML Overview

Here's an analysis of the acceptance criteria and the study that proves the device meets them, based on the provided text:

Acceptance Criteria and Device Performance for ATRISORB® GTR Barrier

The ATRISORB® GTR Barrier aims for substantial equivalence to the predicate device, GORE-TEX® Periodontal Material, for guided tissue regeneration (GTR) in treating Class II furcation defects in humans. Additionally, it claims bioabsorbability and the elimination of a second surgical procedure for removal.

The primary clinical endpoints for demonstrating equivalence were:

Vertical attachment level gain
Horizontal attachment level gain
Pocket depth improvement
Gingival margin location (change)
Bleeding on probing score (change)
Gingival index score (change)
Plaque index score (change)

1. Table of Acceptance Criteria and Reported Device Performance

The study design aimed to show that ATRISORB® GTR barrier was not clinically inferior to GORE-TEX® periodontal material. The null hypothesis tested for some measures was that GORE-TEX® was clinically superior by at least 0.5 mm. The "acceptance criteria" can be inferred from the statistical conclusions, where clinical equivalence was demonstrated if the null hypothesis of significant inferiority was rejected, and confidence intervals supported equivalence.

Measurement	Acceptance Criteria (for equivalence vs. GORE-TEX®)	Reported ATRISORB® GTR Barrier Performance (vs. GORE-TEX®)
Pivotal Trial Outcomes
Vertical Attachment Level Gain	Clinical equivalence demonstrated by rejecting the null hypothesis that GORE-TEX® was clinically superior by at least 0.5 mm (p-value < 0.001) and 95% CI ruling out difference > 0.08 mm in favor of GORE-TEX®.	Achieved Equivalence: Mean increase at Week 52 for ATRISORB® was 0.38 mm greater than for GORE-TEX®. The null hypothesis that GORE-TEX® periodontal material was clinically superior by at least 0.5 mm was rejected (p-value < 0.001). The one-sided confidence interval for the difference ruled out any difference greater than 0.08 mm in favor of GORE-TEX®.
Horizontal Attachment Level Gain	Clinical equivalence demonstrated by rejecting the null hypothesis that GORE-TEX® was clinically superior by at least 0.5 mm (p-value = 0.017) and 95% CI ruling out difference > 0.38 mm.	Achieved Equivalence: Mean increase at Week 52 for ATRISORB® was slightly greater (0.04 mm) than for GORE-TEX®. The null hypothesis that GORE-TEX® periodontal material was clinically superior by at least 0.5 mm was rejected (p-value = 0.017). The one-sided confidence interval ruled out any difference greater than 0.38 mm.
Pocket Depth Improvement	Clinical equivalence demonstrated for the two treatment groups (p-value = 0.024 at baseline, 0.001 at Week 52 for difference) and 95% CI ruling out difference > 0.19 mm.	Achieved Equivalence: Mean decrease at Week 52 was 0.18 mm greater for ATRISORB® subjects than for GORE-TEX® subjects. This significantly satisfied clinical equivalence (p-value for difference at Week 52 = 0.001).
Gingival Margin Recession (Change)	Clinical equivalence demonstrated for the two treatment groups at all time points (p-value < 0.001 at baseline, 0.002 at Week 52 for difference and 95% CI ruling out difference > 0.20 mm).	Achieved Equivalence: Mean increase at Week 52 for ATRISORB® was 0.2 mm less (i.e., less recession or more gain) than for GORE-TEX®.
Bleeding on Probing Score (Change)	Clinical equivalence demonstrated for the two treatment groups at all time points (p-value < 0.001 at baseline, 0.001 at Week 52 for difference and 95% CI ruling out difference > 0.25 mm).	Achieved Equivalence: Mean change at Week 52 for ATRISORB® was slightly greater (0.04 mm - 0.06 mm change, referring to improvement which is a decrease in score) than for GORE-TEX®.
Gingival Index Score (Change)	Clinical equivalence demonstrated for the two treatment groups at all time points (p-value < 0.001 at baseline, <0.001 at Week 52 for difference and 95% CI ruling out difference > 0.17mm).	Achieved Equivalence: Mean change at Week 52 for ATRISORB® was slightly greater (0.07 - 0.10, referring to improvement which is a decrease in score) than for GORE-TEX®.
Plaque Index Score (Change)	Clinical equivalence demonstrated for the two treatment groups at all time points (p-value = 0.015 at baseline, 0.018 at Week 52 for difference and 95% CI ruling out difference > 0.42 mm).	Achieved Equivalence: Mean change at Week 52 for ATRISORB® was 0.15 less (i.e., better) than for GORE-TEX®.
Additional Claims
Bioabsorbability	Complete absorption within a specified timeframe.	Achieved: Preclinical and clinical trials support the claim. Animal studies showed complete absorption by 12 months with one minor exception. This eliminates the need for a second surgical procedure.
Safety and Biocompatibility	No significant toxicity, adverse tissue reactions, or complications compared to predicate or control.	Achieved: In vitro cytotoxicity was mild but inconsistent with in vivo results. Not a skin sensitizer, non-mutagenic, non-pyrogenic. Hemolysis in vitro but unlikely in vivo. Subchronic and chronic implantation studies in rats and rabbits showed no overt toxicity or significant tissue effects, and were well-tolerated. The pivotal human trial reported commonly associated post-operative symptoms but no sensitivity reactions or immune responses related to ATRISORB®.

Overall Conclusion: The studies consistently showed that the ATRISORB® GTR Barrier met the acceptance criteria for substantial equivalence to the GORE-TEX® Periodontal Material across all measured clinical endpoints, and successfully demonstrated the additional claims of bioabsorbability and safety.

2. Sample Sizes Used for the Test Set and Data Provenance

Test Set (Pivotal Clinical Trial):
- 162 subjects were randomized and entered into the 52-week study.
- 82 subjects received ATRISORB® GTR barrier.
- 80 subjects received GORE-TEX® periodontal material.
- For the Week 52 analysis, N varied slightly due to potential dropouts or complete data availability: 66 for ATRISORB® and 63-64 for GORE-TEX® across different measurements.
Data Provenance: The study was a "multicenter clinical trial" in humans. The text does not specify the country of origin, but given the US FDA submission, it is highly probable it was conducted in the United States or under US regulatory oversight. The study was prospective as it involved randomization and follow-up over 52 weeks.

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications

The text does not explicitly state the number of experts or their specific qualifications (e.g., radiologist with X years of experience) used to establish the "ground truth" for the clinical measurements in the pivotal human trial.

However, clinical trials for periodontal research typically involve:

Periodontists or trained dental professionals to conduct the surgical procedures and perform clinical measurements (e.g., probing depth, attachment levels, gingival/plaque indices). These measurements themselves serve as the ground truth for that specific patient's condition at that time point.
For diagnostic accuracy studies, "ground truth" is typically established by consensus of multiple expert readers. For clinical endpoints as measured here, the measurements taken by qualified clinicians during the follow-up themselves constitute the "ground truth" for that trial. The multicenter nature implies multiple clinical sites with their own trained staff.

4. Adjudication Method for the Test Set

The text does not explicitly describe an adjudication method like 2+1 or 3+1 for the clinical measurements. In clinical trials, especially multicenter ones, standardized protocols, calibration of examiners, and blinding (where possible) are used to ensure consistency and reliability of measurements. The "multicenter study with a parallel design" suggests that each site followed a common protocol for data collection.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done

No, an MRMC comparative effectiveness study was not conducted. This study was a clinical trial comparing two medical devices (ATRISORB vs. GORE-TEX) in human patients for treatment outcomes, not an AI efficacy study involving multiple readers interpreting cases. Therefore, there is no effect size reported for human readers improving with AI vs. without AI assistance.

6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) Was Done

No, this is a medical device (a barrier for guided tissue regeneration), not an AI algorithm. Therefore, "standalone (algorithm only without human-in-the-loop performance)" is not applicable to this context. The device directly interacts with human tissue.

7. The Type of Ground Truth Used

For the pivotal clinical trial (test set), the ground truth for effectiveness was clinical measurements (e.g., vertical attachment level, horizontal attachment level, pocket depth) taken directly from human patients by trained clinicians at specified time points, and clinical observations (e.g., bleeding on probing, gingival index, plaque index, postoperative complications).

For bioabsorbability and biocompatibility, the ground truth was established by:

Histological examination in animal studies to confirm barrier degradation and tissue response.
Clinical observation and follow-up in human trials for tissue compatibility and absence of adverse reactions.

8. The Sample Size for the Training Set

This document describes a medical device, not an AI algorithm, so there is no "training set" in the context of machine learning. The studies described (in vitro, animal, and human clinical trials) are for evaluating the safety, biocompatibility, and effectiveness of the physical device.

9. How the Ground Truth for the Training Set Was Established

As there is no "training set" for an AI algorithm in this context, this question is not applicable. The device's "training" or development would have involved iterative research and development, preclinical testing, and eventually clinical trials to refine its formulation and application, culminating in the studies described to demonstrate its safety and efficacy.

Summary

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Image /page/0/Picture/0 description: The image shows the date "SEP 8 1998". The month is abbreviated to three letters. The day is a single digit, and the year is four digits.

2579 MIDPOINT DRIVE FORT COLLINS, CO 80525-4417 U.S.A.

Image /page/0/Picture/2 description: The image shows the logo for Atrix Laboratories, Inc. The logo features a stylized sunburst design above the company name. The sunburst is composed of several thick, black lines radiating upwards and outwards from a central point. Below the sunburst, the word "ATRIX" is printed in a bold, sans-serif font, and beneath that, the words "LABORATORIES, INC" are printed in a smaller, sans-serif font.

K982865

PHONE: (970) 482-5868
EMAIL: atrixlab@frii.com http://www.atrixlabs.com

510(k) Summary of Safety and Effectiveness

1. General Information

Manufacturer:	Atrix Laboratories, Inc.2579 Midpoint DriveFort Collins, CO 80525-4417Telephone: 970-482-5868Fax: 970-482-9735
Contact:	Elaine M. Gazdeck, R.A.C.Vice President, Regulatory Affairs/Quality
Device Generic Name:	Bioabsorbable GTR Barrier Kit (used to form aBioabsorbable GTR Barrier)
Device Trade Name:	ATRISORB® Bioabsorbable Guided TissueRegeneration (GTR) Barrier Kit (used to form anATRISORB® Bioabsorbable GTR Barrier)
510(k) Clearance Numberfor Unmodified Device:	K955838
510(k) Clearance Numberfor Modified Device:	K
Date Prepared:	July 1, 1998
Predicate Device:	GORE-TEX® Periodontal Material

1. Description

1.1. Formulation

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2.2. Device

The finished device is provided in two different packaging configurations. The first configuration is the ATRISORB® GTR Barner Kit (case kit) used to form either with the barrier-forming case (extraoral) or by direct application over bone grafting material. The second configuration is the ATRISORB® GTR Barrier multipack (multipack) used only for the direct application technique.

The ATRISORB® GTR Barrier Kit configuration contains a foil-pouched, single-patient use dose pack containing 0.5 g of ATRISORB® polymer formulation, a pouched tray that contains a barrier forming case and three units of 0.9% sodium chloride solution (pH range 3.5 - 6.0), and an instructions for use booklet.

The barrier forming case has two sections of porous pads held in the cavities of the case and two spacers that are loose in the case. A label with a 1 mm grid pattern is affixed to the underside of the case. This grid is visible through the case and allows an area on the inside of the case to be used for trimming the formed barrier

The ATRISORB® GTR Barrier multipack configuration consists of three foilpouched, single patient use dose packs containing 0.5 g of the ATRISORB® polymer formulation, three 18 gauge cannulae, and an instructions for use booklet.

3. Mechanics

The ATRISORB® GTR barrier functions as a guided tissue regeneration barrier by isolating the regenerative surgical site from the adjacent gingival connective tissue and epithelium. This facilitates population of the surgical site with cells from the periodontal ligament and adjacent alveolar bone that lead to regeneration.

The ATRISORB® polymer formulation is a flowable solution. A preformed GTR barner, with consistent thickness, is prepared by using a barrier forming kit. The flowable formulation partially precipitates when it is "sandwiched" between two porous pads which are wetted with sodium chloride solution contained in a barrier forming case. The barrier thickness is determined by the thickness of the spacers which hold the two porous pads apart. The barrier, which is prepared in approximately three to six minutes, can be trimmed to the required size and morphology of the defect. The formed ATRISORB® GTR barner is applied to the defect

Another method of forming the barrier can be accomplished in situ where the tissue fluid aids in the precipitation of the barrier at the defect site. For defects where bone replacement graft material has been applied, the flowable formulation can be applied directly over the grafting material. Extraoral formation (formed in the case) is required when grafting materials are not used, as the unprecipitated formulation would flow into the defect.

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With either method of application, the formed barrier is a film which covers the defect. Once in place, it continues to solidify and the resulting barrer precludes the migration of epithelial or connective tissue cells through it, and simultaneously isolates the periodontal compartment, thereby facilitating regeneration. The chemistry of the ATRISORB® polymer formulation is such that, after setting, the polymer component subsequently bioabsorbs through the process of hydrolysis. Bioabsorption occurs over the course of several months. The barrier is present and intact during the critical period when periodontal regenerative cells are proliferating during the wound healing cascade from adjacent periodontal sources.

4. Intended Use

The clinical indications for the ATRISORB® GTR Barrier are for GTR procedures in the surgical treatment of Class II furcations, or 2 and/or 3 walled intra-osseous defects and dehisence defects to aid in the regeneration and integration of periodontal tissue components.

The indications for the ATRISORB® GTR barrier are equivalent to the indications for the predicate device, expanded polytetrafluoroethylene (e-PTFE) GORF-TEX® Periodontal Material (W.L. Gore & Assoc., Flagstaff, AZ).

The indications that differ are for bioabsorbability and elimination of a second surgical procedure to remove a non-bioabsorbable material. Results of preclinical and clinical trials support the claim of bioabsorbability and good tissue compatibility.

The predicate device, GORE-TEX® Periodontal Material, is indicated as an implantable material to aid in the healing of periodontal defects. The GORE-TEX® Periodontal Material is non-bioabsorbable and requires a second surgical procedure to remove it.

5. Summary of In Vitro Studies

5.1. Cytotoxicity

The study evaluated the toxic effects of the ATRISORB® GTR barrier upon mature monolayer tissue cultures of L929 cells. The ATRISORB® GTR barrier is mildly cytotoxic; however, these results are not consistent with results from more meaningful, in vivo implantation and clinical studies on the barrier.

5.2. Sensitization

A guinea pig maximization test, based on the method of Magnusson and Kligman (1970), was used to evaluate the potential of the ATRISORB® polymer formulation to elicit delayed dermal contact sensitization. The ATRISORB® polymer formulation is not a skin sensitizer

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Genotoxicity 5.3.

Genotoxicity
The study evaluated the mutagenicity of an extract of the ATRISORB® The study evaluated the mutagencity of an extract of the mulation is not mutagenic.
polymer formulation. The ATRISORB® polymer formulation is not mutagenic.

Pyrogenicity - Limulus Amebocyte Lysate Test (LAL) 5.4.

Pyrogenicity - Limules Almaded the concentration of bacterial endotoxins in an extract
The LAL test estimated the concentration of bacterial non-The LAL test estimated the concentration of becamer is nonpyrogenic according to this test method.

Hemolysis 5.5.

The ATRISORB® GTR barrier causes hemolysis in an in vitro test system, The ATRISORB® GTR Dannel Causes hemolysis in patients treated with the barrier.
but it is highly unlikely to cause hemolysis in patients begolvice potential using but it is highly unlikely to cause nemorysis nemolytic potential using
The study evaluated the ATRISORR® GTR barner's hemolytic potential using The study evaluated the ATKION City of the Buffering capacity. The barrier
human blood in an in vitro system with the black and the NMP human blood in an in vitro system title blood path and the NMP does not have significant contact with the blood personal.
concentrations in this assay may have been far greater than that which could be attained in the human body.

Based upon this analysis, the ATRISORB® GTR berner's in vitro hemolytic Based upon this analysis, the ATTATCOND of the barrier in accordance with the barrier's intended use.

Sterilization 5.6.

The ATRISORB® GTR Barrier Kit and ATRISORB® GTR Barrier are The ATRISORD® GTK Banier Tat and Arradiation. The cannulae in the terminally sterilized by Costing are provided sterile by the manufacturer and are not further processed.

Bioburden 5.7.

Bioburden determination is performed prior to sterilization following USP procedures.

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6. Summary of In Vivo Implantation Studies

Subchronic Implantation 6.1.

Subchronic implantation
The study evaluated the biocompatibility of the rat . During the course o The study evaluated the blocompanism of the rest. During the course of the when surgically implanted subcularied around any of the test implantation sites study, no toxicity was observed around any of the toot major and the locked to the really was observed
which could be directly related to the barrier. No overt toxicity was which could bing the course of the study.

The subcutaneous implantation of the ATRISORB® GTR barner in rats for a
rt a many and the country to this taxicity The subcatures and not result in toxicity.

Chronic Implantation and Biodegradation 6.2.

Chronic Imprantation and Libers of the ATRISORB® GTRISORB® GTR
The study evaluated (1) the degradation kinetics of the controls The study evaluated (1) the degradation hiriclib the barner The controls for
barrier, and (2) response of tissue in contact with the barner of the test and barrier, and (2) response of tissue in concess winding of the test and
the study were USP plastic strips. Histological examination of the test and the study were USP plastic surpos. This signs of biologically significant
control excised implant sites showed no significant difference between control excised implant sites showed no significant difference between the
changes or abnormal tissue. There was no significant dissue effects. changes or abnormal tissue. There was no significant and control sites .
ATRISORB® GTR barrier sites and control sites with respect to tissue effects.

The study demonstrated that the ATRISORB® GTR barrier does not ellicit The study demonstrated the the ATRIONDO Shipping on rabbits for up
toxicity (dermal or systemic) when subcutaneously implanted in rabbits for up toxicity (dermal or systemic) when subculariously implication of the ATRISORB® GTR barrier should
to twelve months and biodegradation of the ATRISORB® GTR barrier should be complete by 13-14 months.

7. Summary of Animal Efficacy Studies

Histology Study 7.1.

This study compared the safety, clinical results, and histologic effects of This study compared the Sately, cirinour returns in six adult beagle dogs
ATRISORB® GTR barriers to sham operated controls in six adult beagle dogs ATRISORD® GTR Barnors is unam of them on tall furcation defects.

A periodontal surgeon selected and prepared 16 study sites as follows: a full A periodontal surgeon selector and propares was reflected, plaque and thickness ilap created after giftgirds increasing devices, and roots planed by hand. calculus were removed with ultrasonic were applied to eight test sites, all
Preformed ATRISORB® GTR barriers were applied to eight test sites, all Preformed ATRISORD® OTTS Barner . Post-surgery periodontal maintenance
study sites were closed and sutured. Post-surgery periodontal maintenance sites were closed and Sularou. T est only inse to all study sites for consisted on topical applications or shed using a modified Bass technique wo months, then the teen were bradned as a graintegrity, clinical conditions, with brushes soaked in Pendox® crainment of the study. All of the animals were sacrificed after six months of observation.

The ATRISORB® GTR barrier demonstrated clinically and statistically The ATRIONDO OTHe depth, horizontal furcation depth, and improved superior results in position as a more significantly increased the

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amount of periodontal regeneration (i.e., new bone, cementum, and amount of periodontal regeneration (f.e., hew bone, before, before, and toxicity
periodontal ligament formation) in the furcation defect. No signs of toxicity were observed.

Biodegradation and Safety Study 7.2.

Biodegradation and Safety Study
The object of this study was to evaluate the potential for clinical application, The object of this study was to evaluate the potential hor and the polymer
clinical management, safety and biocompatibility of a biodegradable polymer clinical management, salety and blockhpanding or cated to facilitate groend thissue
barrier preformed in a barrier forming device to facilitate in the barrier preformed in a barner forming device to fallance a maxilla in the dog.
regeneration at periodontal defects in the study and 17 naturally occurring defects regeneration at periodontal detects in the study and 17 naturally occurring defects
Seven beagle dogs were used in the study and 17 naturally were treated. Twelve periodontal furcation defects were treated surgically were treated. Twelve pendontal furcation if the barriers formed with three
with ATRISORB® GTR barriers to determine if the bartiers formed with three with ATRISORB® GTR barners to determine if the barners for the world.
prototype kits compared favorably to 5 sham operated controls in terms of
the supers of the company to safety and biocompatibility.

The ATRISORB® GTR barrier was well tolerated in all periodontal test sites
in the ATRISOR was and continues inflammation compared to control The ATRISORB® GTR barner was well tolerated in all por
and produced no increases in localized inflammation compared to control sites.

Use of the ATRISORB® GTR barrier in treating periodontal defects in the dog
ing and the collection birthlaniael evidence of adverse healing and Use of the ATRISORB® GTTA banier in treating for a resulted in no clinical or histological evidence of dover of the end of one vear.

Histological examination confirmed that barriers were completely absorbed at
the examination and confinent and spicule found in one out of twelve Histological examination confilmed that bamore word in one out of twelve
12 months with the exception of one small spicule found in one out of twelve test sites.

Pilot Study 7.3.

Pliot Study
This study was a pilot study designed to examine four compositions of This study was a pilot study designed to oxepare the ATRISORB® GTR ATRISORB® polymer formulation used to propare tissue regeneration in the periodontal region.

Thirty-nine defects were treated in six beagle dogs. All dogs were terminated I hirty-hine defects were treated in six bearier placement. The study
between 9 and 12 months following initial bearier placement, The study between 9 and 12 months lollowing think barner pecome reconstituted on root
showed that new periodontal supporting tissues became reconstituted on root showed that hew penodonial burgically-induced and naturally-occurring and furcation sunasse in ssirg. The ATRISORB® GTR barrier.

Feasibility Study 7.4.

The objective of this study was to evaluate the safety and potential of a The objective of this study was to overse to facilitate periodontal synthetically formulated nowable polymer same to the canine and

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molar regions of dogs over a period of 3 months. Two dogs were used with a moral regions of "dogeier sites and 8 control sites) being treated.

The results of this study demonstrated the potential safety and the ability of l he results of this study demonstration the polymers to facilitate periodontal tissue regeneration.

8. Summary of Pivotal Trial

A pivotal clinical trial under an FDA Investigational Device Exemption was conducted A pivotal cillinear that chuck and efficacy of the ATRISORB® GTR Barrier Kit in a multicenter clinical trial.

The primary object of the study was to demonstrate that the ATRISORB® GTR The primally object of the study was to GRE-TEX® periodontal material for guided tissue regeneration (GTR) treatment of Class II furcation defects in humans. The tissue regeneration (GTTY) a cannertical and horizontal attachment level, with primally clinical end points were vig pocket depth, bleeding on probing, gingival margin location, and gingival index.

The investigation was a multicenter study with a paralled design. Individuals with a The investigation was a mailies national with either ATRISORB® GTR barrier or Glass in furcation delect were troulou with on randomized treatment assignment. OUtcomes of healing were evaluated at regular intervals up to one year after the Outcomes of nealing were comparisons of clinical results between the two products were made in order to demonstrate substantial equivalency between the were made in order to riement GORE-TEX® periodontal material in guided tissue regeneration treating Class II furcation defects.

One hundred sixty-two subjects were randomized and entered into this 52-week one handroo oxly the sabjects are a learner and 80 subjects received GORE-TEX® periodontal material. Subjects were selected if they met the following entry criteria:

A Class II furcation with vertical pocket depth []5 mm and attachment loss at the site and the horizontal depth of the furcation was 03 mm
Between the ages of 25 and 75 .
. in good general health

Radiographs were taken within the two months prior to Screening or at the Screening or Baseline visit, and provided evidence of crestal alveolar bone loss associated with periodontitis.

The study demonstrated that ATRISORB® GTR barner is substantially equivalent to the predicate device, GORE-TEX® periodontal material for the treatment of periodontal defects using guided tissue regeneration procedures.

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The safety results over the 52-week duration of the study support the benign The salety results over the ose of the ATRISORB® GTR barrier.

Summary of the Statistical Analysis of the Data from the Pivotal Clinical 8.1. Trial

The following tabulation presents the data for ATRISORB® GTR barrier vs. GORE-TEX® periodontal material at Baseline and Week 52. Vertical attachment level gain significantly satisfied the condition of clinical attachment level gall regility wo treatment groups at Week 52. The mean equivalence between the the treated with ATRISORB® GTR barner was 0.38 mm greater than the mean for subjects treated with GORE-TEX® periodontal material. The null hypothesis that GORE-TEX® periodontal material was clinically superior by at least 0.5 mm was rejected with a p-value of less than 0.001. The one-sided confidence interval for the difference of less than 0.00 . - TRUSORB® GTR barrier and the GORE-TEX® periodontal between the ATTRICO any difference greater than 0.08 mm in favor of GORE-TEX® periodontal material can be ruled out with 95% confidence.

Horizontal attachment level gain significantly satisfied the condition of clinical equivalence between the two treatment groups at Week 52. The mean increase at Week 52 for subjects treated with ATRISORB® GTR barrier was slightly greater (0.04 mm) than the mean for subjects treated with GORE-TEX® periodontal material. The null hypothesis that GORE-TEX® periodontal material was clinically superior by at least 0.5 mm was rejected with a p-value of 0.017. The one-sided confidence interval for the difference in treatment effects indicates that any difference greater than 0.38 mm can be ruled out with 95% confidence.

Pocket depth improvement significantly satisfied the condition of clinical equivalence for the two treatment groups at Week 52. The mean decrease at Week 52 was 0.18 mm greater for ATRISORB® GTR barrier subjects than the mean decrease for subjects treated with GORE-TEX® periodontal material.

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Measurement	Time Point	ATRISORB® GTR Barrier			GORE-TEX® Periodontal Material			GORE-TEX® Periodontal Material Minus ATRISORB® GTR Barrier Difference	P-value*	One-sided* Confidence Interval
		N	Mean	S.E.	N	Mean	S.E.
Vertical Attachment Level	Baseline**Week 52	76	5.82	0.21	73	5.74	0.20	-0.08	0.009	0.30
		66	2.00	0.19	64	1.63	0.20	-0.38	<0.001	0.08
Horizontal Attachment Level	Baseline**Week 52	76	4.57	0.14	73	4.77	0.15	0.20	0.010	0.34
		66	2.11	0.20	64	2.06	0.16	-0.04	0.017	0.38
Pocket Depth	Baseline**Week 52	76	5.55	0.11	73	5.55	0.10	-0.00	0.024	0.43
		66	2.26	0.16	64	2.08	0.15	-0.18	0.001	0.19
Gingival Margin	Baseline**Week 52	76	-0.26	0.19	73	-0.19	0.19	0.07	<0.001	0.15
		66	-0.26	0.15	64	-0.45	0.18	-0.20	0.002	0.20
Bleeding on Probing	Baseline**Week 52	76	1.34	0.09	72	1.17	0.09	-0.18	<0.001	0.12
		66	0.85	0.14	64	0.81	0.11	-0.04	0.001	0.25
Plaque Index	Baseline**Week 52	76	0.68	0.08	73	0.84	0.09	0.15	0.015	0.42
		66	0.15	0.12	64	0.30	0.12	0.15	0.018	0.42
Gingival Index	Baseline**Week 52	76	1.32	0.08	72	1.19	0.08	-0.12	<0.001	0.10
		66	0.48	0.13	63	0.38	0.11	-0.10	<0.001	0.17

Gingival margin recession significantly satisfied the condition of clinical equivalence for the two treatment groups at all time points. The mean increase at Week 52 for subjects treated with ATRISORB® GTR barner was 0.2 mm less than the mean increase for subjects treated with GORE-TEX® periodontal material.

Bleeding on probing score significantly satisfied the condition of clinical equivalence for the two treatment groups at all time points. The mean change at Week 52 for subjects treated with ATRISORB® GTR barrier was slightly greater (0.04 mm - 0.06 mm) than the mean change for subjects treated with GORE-TEX® periodontal material.

Gingival index score significantly satisfied the condition of clinical equivalence for the two treatment groups at all time points. The mean change at Week 52 for subjects treated with ATRISORB® GTR barrier was slightly greater (0.07 - 0.10) than the mean change for subjects treated with GORE-TEX® periodontal material.

Plaque index score significantly satisfied the condition of clinical equivalence for the two treatment groups at all time points. The mean change at Week 52 for subjects treated with ATRISORB® GTR barrier was 0.15 less than the mean change for subjects treated with GORE-TEX® periodontal material.

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Postoperative Complications 8.2.

Postoperative symptoms or complications that were reported were those commonly associated with oral or periodontal surgical procedures, such as intra oral swelling associated with offer of penodonial ourgroup without treatment or in some cases and pain which usually rodorroules. These events occurred in both test and control treatments.

There were no sensitivity.reactions or immune responses associated with the use of the ATRISORB® GTR barrier.

9. Direct Application

Case studies were conducted with the direct application of the barrier over bone Gase Studies were conteen subjects with a total of twenty-two periodontal defects of grarting matchan. Eightedn and it was determined that the material was suitable varying comploxity word troutes and determined by clinical measurements and reentry surgeries. These cases were followed and no adverse sequela were observed. encry Surgerior "The direct application of the ATRISORB® GTR Barrier has These using and is a suitable alternative to forming the barrier in the precipitation case.

10. Conclusions

The claims for the ATRISORB® GTR Barrier Kit and the ATRISORB® GTR Barrier are equivalent to the claims for the predicate device, GORE-TEX® Periodontal Material. Additional claims for the ATRISORB® GTR Barrier are for bioabsorbability and elimination of a second surgical procedure to remove the non-bioabsorbable GORE-TEX® Periodontal Material. The features of the ATRISORB® GTR Barrier compared to the GORE-TEX® Periodontal Material are described below.

Human clinical trials have demonstrated that the ATRISORB® GTR Barrier is equivalent to the non-bioabsorbable GORE-TEX® Periodontal Material as an implantable material intended to aid in the healing of periodontal defects.

The ATRISORB® GTR Barrier is bioabsorbed, eliminating the need for a second surgical procedure such as that required to remove the non-bioabsorbable membrane, GORE-TEX® Periodontal Material.

Preclinical and clinical trial studies have demonstrated the ATRISORB® GTR Barrier to be safe and effective in the treatment of periodontal defects when formed either using the barrier forming case or the direct application technique.

The ATRISORB® GTR Barrier is non-pyrogenic and is biocompatible.

In vitro, animal. and clinical studies have demonstrated that the ATRISORB® GTR Barrier is safe and effective for its stated indications and is substantially equivalent to the predicate device, GORE-TEX® Periodontal Material.

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Image /page/10/Picture/1 description: The image shows the logo for the U.S. Department of Health & Human Services. The logo consists of a circular border with the text "DEPARTMENT OF HEALTH & HUMAN SERVICES · USA" arranged around the top half of the circle. Inside the circle is a stylized image of an eagle or bird in flight, formed by three curved lines that also resemble human profiles facing to the right.

Public Health Service

Food and Drug Administration 9200 Corporate Boulevard Rockville, Maryland 20850

OCT 1 0 2007

Elyse Wolff, MT (ASCP) Regulatory Project Leader Atrix Laboratories, Incorporated 2579 Midpoint Drive Fort Collins, Colorado 80525-4417

Re: K982865

Trade Name: ATRISORB® Bioabsorbable Guided Tissue Regeneration (GTR) Barrier Regulation Number: 872.3930 Regulation Name: Bone Grafting Material Regulatory Class: 2 Product Code: NPK Dated: July 1, 1998 Received: August 13, 1998

Dear Ms. Wolff:

This letter corrects our substantially equivalent letter of September 8, 1998.

We have reviewed your Section 510(k) premarket notification of intent to market the device referenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act) that do not require approval of a premarket approval (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.

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Page 2 -

Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (sections 531-542 of the Act); 21 CFR 1000-1050.

This letter will allow you to continue marketing your device as described in your Section 510(k) premarket notification. The FDA finding of substantial equivalence of your device to a legally marketed predicate device results in a classification for your device and thus, permits your device to proceed to the market.

If you desire specific advice for your device on our labeling regulation (21 CFR Part 801), please contact the Office of Compliance at (240) 276-0115. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21CFR Part 807.97). You may obtain other general information on your responsibilities under the Act from the Division of Small Manufacturers, International and Consumer Assistance at its toll-free number (800) 638-2041 or (240) 276-3150 or at its Internet address http://www.fda.gov/cdrh/dsma/dsmamain.html

Sincerely yours,

Spitte y. Michluams.

Chiu Lin, Ph.D. Director Division of Anesthesiology, General Hospital, Infection Control and Dental Devices Office of Device Evaluation Center for Devices and Radiological Health

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Protecting and Promoting Public Health

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1 of 1

K982865

-K955838 (Unmodified Device) 510(k) Number (if knc wn):

ATRISORB® GTR Barrier Device Name:

Indications For Use:

(PLEASE DO NOT VRITE BELOW THIS LINE - CONTINUE ON ANOTHER PAGE IF NEEDED)

Concurrence of CDRH, Office of Device Evaluation (ODE)

Susan Runne

(Division Sign-Off) Division of Dental, Infection Control, and General Hospital Devices Kh 510(k) Number

Prescription Use V (Per 21 CFR 801.109) --

Over-The-Counter Use

(Optional Format 1-2-96)

Regulation Number and Section

§ 872.3930 Bone grafting material.

(a)
Identification. Bone grafting material is a material such as hydroxyapatite, tricalcium phosphate, polylactic and polyglycolic acids, or collagen, that is intended to fill, augment, or reconstruct periodontal or bony defects of the oral and maxillofacial region.(b)
Classification. (1) Class II (special controls) for bone grafting materials that do not contain a drug that is a therapeutic biologic. The special control is FDA's “Class II Special Controls Guidance Document: Dental Bone Grafting Material Devices.” (See § 872.1(e) for the availability of this guidance document.)(2) Class III (premarket approval) for bone grafting materials that contain a drug that is a therapeutic biologic. Bone grafting materials that contain a drug that is a therapeutic biologic, such as biological response modifiers, require premarket approval.
(c)
Date premarket approval application (PMA) or notice of product development protocol (PDP) is required. Devices described in paragraph (b)(2) of this section shall have an approved PMA or a declared completed PDP in effect before being placed in commercial distribution.