Effect of two bioabsorbable barrier membranes on bone regeneration of standardized defects in calvarial bone: a comparative histomorphometric study in pigs

BACKGROUND: The effect of two different bioabsorbable collagen membranes on bone regeneration was assessed in standardized, membrane-protected calvarial defects in pigs. METHODS: Two standardized defect types (6 x 6 x 6 mm and 9 x 9 x 9 mm) were produced in the calvaria of pigs: empty defects without a membrane (group 1; eight defects per size); defects filled with deproteinized bovine bone mineral (DBBM) without a membrane (group 2; eight defects per size); defects filled with DBBM and covered by a collagen membrane (group 3; eight defects per size); and defects filled with DBBM and covered by a cross-linked collagen membrane (CCM) (group 4; eight defects per size). Sacrifice took place 16 weeks after surgery, and the following parameters were analyzed: descriptive histology; semiquantitative histology (SQH), assessing bone regeneration in the whole defect area; and histomorphometric analysis of the percentage of bone and DBBM in the regenerated area at three different depth levels of the defect. RESULTS: Using SQH, both membrane types resulted in significantly better bone regeneration compared to groups 1 and 2, irrespective of the defect size (P <0.005), with no difference between the two membranes. In the histomorphometric analysis, the layer immediately below the surface exhibited a significantly higher percentage of bone in groups 3 (27%) and 4 (36%) versus the two other groups for the 9 x 9 x 9-mm defects. No such differences were apparent for the 6 x 6 x 6-mm defects or the other two depth levels (bottom and middle layer) for either defect size. CONCLUSIONS: The two collagen membranes tested significantly enhanced bone regeneration, especially in the superficial level of the calvarial bone defects. The prototype CCM did not provide any further advantage in the present animal model.

The social evil in Chicago: a study of existing conditions with recommendations by the Vice Commission of Chicago, a municipal body appointed by the Mayor and the City Council of the City of Chicago, and submitted as its report to the Mayor and City Council of Chicago

Preface -- Outline of study -- Resolution of appreciation -- Introduction and summary -- Proposed ordinance -- Recommendations -- Existing conditions in Chicago -- The social evil and the saloon -- The social evil and the police -- Sources of supply -- Child protection and education -- Rescue and reform -- The social evil and its medical aspects -- Appendices: Text of revised statutes of Illinois and ordinances of the City of Chicago ; Tables ; Exhibits.

Catharine Waugh McCullouch papers in the Mary Earhart Dillon collection, 1869-1945

Collection primarily documents McCulloch's research on women's legal status, and her work with the Illinois Equal Suffrage Association, the National American Woman Suffrage Association, and the League of Women Voters. There is also documentation of women in the legal profession, of McCulloch's friendships with the other women suffragists and lawyers, and some biographical material. The papers contain little information about her family or social life.

Bulletin / Chicago Natural History Museum.

v. 29 (1958)

Bulletin / Chicago Natural History Museum.

v. 33 (1962)

Bulletin / Chicago Natural History Museum.

v. 20 (1949)

Bulletin / Chicago Natural History Museum.

v. 15 (1944)

Bulletin / Chicago Natural History Museum.

v. 19 (1948)

Bulletin / Chicago Natural History Museum.

v. 23 (1952)

Bulletin / Chicago Natural History Museum.

v. 16 (1945)

Bulletin / Chicago Natural History Museum.

v. 34 (1963)

Bulletin / Chicago Natural History Museum.

v. 18 (1947)

Bulletin / Chicago Natural History Museum.

v. 25 (1954)