Impaired migration of epidermal cells from decubitus ulcers in cell cultures. A cause of protracted wound healing?

Cultured epidermal cells of explants from decubitus ulcer edges showed significant (P less than 0.05) decreased maximal growth rate (range, 1.3-15.6%) and decreased area of outgrowth per explant (mean and SD, 1.6 +/- 1.7 mm2) when compared with explants obtained 4-5 cm distant from the ulcer edge (range, 46.7-68.8% and 4.6 +/- 2.7 mm2, respectively) and from healthy skin (range, 78.8-93.3% and 6.6 +/- 1.2 mm2, respectively). In contrast, epidermal cells in biopsies from the ulcer edge were significantly (P less than 0.05) more prevalent (range, 1.9-48.2%) as compared with biopsies of healthy skin (range, 3.1-5.1%). Therefore, the decreased growth rate and decreased area of outgrowth may be caused by a defective migration potential rather than an impaired mitotic activity. The latter seems to be normal, as demonstrated by the histomorphometry, which indicates the in vivo situation. Decreased migration potential of epidermal cells could explain the clinically observed protracted epithelialization of decubitus ulcers.

[The effect of bioceramics (calcium phosphate ceramics) on cultured rabbit fibroblasts]. / Die Wirkung von Biokeramik (Kalziumphosphatkeramik) auf kultivierte Kaninchenfibroblasten.

Cell compatibility of biodegradable calciumphosphate ceramic material was tested in rabbit fibroblasts cultivated on cover slips. Culture growth was in no way inhibited during 12 days of cultivation in the presence of ceramics. The fibroblasts showed phagocytosis of ceramic particles and were able to undergo mitosis as long as the cytoplasm was not overloaded with particles. After incorporation of ceramics, impairment of cytoplasmic division could lead to the formation of polyploid and polynuclear cells. Death of overloaded cells was observed only in the cell-and ceramic-dense center of the cultures from the 10th day on, and may be considered as natural decay of aged cells. The cell- and tissue-compatibility of bioceramic material observed in experimental surgery is thus confirmed.

Influence of chlorhexidine rinsing on the healing of oral mucosa and osseous lesions.

The influence of chlorhexidine rinsing on wound healing was studied using standardized, open mucosal-osseous wounds in the left side of the palate in Wistar rats. In five test groups, each containing 10 rats, rinsing was performed twice daily for 30 sec with 0.1, 0.2 and 0.5% chlorhexidine solution, chlorhexidine solution vehicle, and Ringer solution. A sixth test group (control) was not rinsed at all. Seven days postoperatively, wound healing was evaluated clinically (size of the defect) and histomorphometrically (percent composition of mature connective tissue, immature connective tissue, granulation tissue, fibrin with granulocytic infiltrate). Clinically it was clear that wound healing was best in those animals that rinsed with Ringer solution, and worst in those that rinsed with 0.5% chlorhexidine solution. Increasing concentration of chlorhexidine caused a delay in wound healing, which in the following cases resulted in significant differences: rinsing with Ringer solution and vehicle versus all concentrations of chlorhexidine, no rinsing versus 0.5% chlorhexidine. Intensive rinsing with high concentrations of chlorhexidine may, after oral surgical operations, especially surgery in which bone is exposed, result in delay and disturbance of wound healing in humans.

[Comparative clinical and histological studies on extraction wounds with and without local application of a salicylic acid preparation (Apernyl)]. / Vergleichende klinische und histologische Untersuchungen an Extraktionswunden mit und ohne lokale Applikation eines Salicylsäurepräparates (Apernyl)

Selected patients with extraction wounds served to experiment with Apernyl-styli of Bayer. Contralateral alveoli were used as controls. 10 days following operation biopsies were taken from treated and untreated alveoli. Histologically, a morphometric study was made, and clinically healing was judged by the frequency of complications and the initial physiologic pain. The results show that Apernyl does not influence histological healing, positively or negatively. Thus, the results obtained by Nordenram and Band (1970) and Satoh et al. (1973) could be confirmed. Clinically, there were significanlty less p.o. complications in patients with Apernyl prophylaxis; 2 of 51 treated alveoli compared to 8 of 45 untreated ones. Pain was significantly reduced: 17 of the 19 patients complained of pain in the untreated half of the jaw, while only 4 suffered pain on the treated side. This confirms the findings of Neuner and Panzera and Neuner and Schegg (1972 and 1969 resp.).

[Mobility measurements and histological studies on endosseous titanium implants under masticatory stress in the mandibles of adult macacas]. / Beweglichkeitsmessungen und histologische Untersuchungen an kaufunktionell belasteten, enossalen Titaniumimplantaten in Unterkiefern adulter Bärenmakaken.

Linkow blades were implanted into 5 adult monkeys. Measurements of mobility showed that two weeks after implantation the implant mobility was below the mobility of the control teeth. Fixed bridgework was inserted and after 8-14 months the mobility of implant and control teeth were alike. Inspite of this favourable result, the mobility of the implants, after removal of the bridgework, was higher than that of the controls and of normal values. The histological picture explains this, since all implants showed a sheath of connective tissue which was 5-10 times the dimension of the normal desmodontal space. Inflammatory processes and epithelial growth into depth were observed inspite of the absence of clinical symptoms. There was bony growth through the windows of the implants, but only on two implants could bone sheathing be observed. The conclusion is that Linkow implants should not be used alone for the anchoring of bridgework but only as link supports between long bridge spans or as distal extension of shortened tooth arches. Also, it can be used for the retention of a Dolder bar in mucosa supported dentures.

Correlations among Papilla Bleeding Index, other clinical indices and histologically determined inflammation of gingival papilla.

The Papilla Bleeding Index (PBI) was measured on 95 interdental papillae, after which the results were compared to Sulcus Bleeding Index (SBI) scores, sulcus fluid (SF) amounts and pocket depth (PD) measurements. In 52 of the papillae, a histological evaluation of the degree of inflammation was also made, in which not only the expanse of the infiltrate but also its intensity were of interest. The PBI was positively correlated with all of the other clinical indices. Obvious and highly statistically significant correlations were demonstrated among PBI, SBI and SF. In contrast, between PBI and PD, and between SBI and PD, only weak correlations were found. The comparison of the PBI with the histological determination of inflammation revealed a clear increase in the absolute amount of inflammatory infiltrate as PBI scores increased. In addition, there was a definitive shift in the intensity of the infiltration; moderate and severe areas of infiltration became more common as PBI scores went up.