Oxidative phosphorylation in rat oral mucosal mitochondria.

Oral mucosal mitochondria were isolated and characterized morphologically by electron microscopy. Polarographic measurements were made of respiration and oxidative phosphorylation in the mitochondrial preparations. ADP:O ratios approaching or slightly exceeding the theoretical maxima and stabilized respiratory control ratios were achieved with malate + glutamate, succinate and ascorbate-N,N,N1N1 tetramethyl-p-phenylenediamine (TMPD) as substrates. Inhibition by rotenone, antimycin A, azide, and cyanide established the classical electron transport chain as the major pathway of mitochondrial respiration. Respiration of the oral mucosal mitochondria was stimulated by DNP in the presence of succinate. DNP-stimulated respiration exceeded that observed in the presence of ADP plus Pi and increasing the concentration of DNP progressively inhibited respiration.

Antibiotics and the intraoral abscess.

Sensitivity tests were administered to determine the effectiveness of several antibiotics in the management of the oral abscess. Cultures were taken from 13 patients who were diagnosed as having either a periodontal or periapical abscess. Results revealed the following 1. The most effective antibiotic was Chloromycetin. Yet it was felt that its medical contraindications far outweigh its use by the dental practitioner. 2. Tetracycline was the least effective antibiotic. 3. Penicillin, because of its high potency against microorganisms of the dental abscess, should be considered the drug of choice. Its use, however, must be restricted to patients who give a negative history to allergies and/or asthma; when such a history is positive, erythromycin should be used. 4. Appropriate culture and sensitivity tests should be performed to determine the susceptibility of the causative organism(s) to the drug of choice.

Salivary composition and calculus formation in patients undergoing hemodialysis.

The purpose of this report is to provide further information regarding oral changes in patients with chronic renal disease who are undergoing hemodialysis. Quantitative changes in salivary flow rate and alterations in the composition of stimulated and unstimulated sliva were studied along with the rate of formation of supragingival calculus. Results revealed a lower salivary flow rate and increased salivary urea concentration in the dialysis group. Dialysis patients also formed more heavy calculus.

Combined orthodontic-periodontal treatment of an infrabony defect. A case report.

A case presentation involving the combined orthodontic-periodontic treatment of a distally inclined mandibular left central incisor with a mesial infrabony defect is reported. Treatment was performed in three phases: (a) the tooth was moved upright (b) periodontal surgery with osseous grafting of the infrabony defect was then performed; and (c) the operative site was reentered 5 months later. The patient was followed and soft and hard tissue changes were documented for 12 months from time of initiation of treatment.

Human clinical and histologic responses to Durapatite implants in intraosseous lesions. Case reports.

The healing response following implantation of a nonresorbable ceramic (durapatite) into human periodontal osseous defects was evaluated clinically and histologically. Four tooth-containing blocks were obtained from four patients who had received durapatite implants in osseous defects, each exceeding 4 mm in depth. Each patient was seen for 5 to 13 postsurgical maintenance visits. Teeth in block section were removed between 8 weeks and 8 months postgraft surgery. Clinical evaluation of the repair process demonstrated that pocket depth decreased in all four cases. Histological evaluation of the repair process showed no indication of new periodontal attachment, osteogenesis or cementogenesis, in the host tissues adjacent to the graft particles. Pocket closure appeared to occur by means of a long junctional epithelium and connective tissue adhesions. There was minimal or no evidence of inflammation in all sections associated with the implant. The graft material therefore acted as a biocompatible foreign body within the gingival tissue.

Osseous autografts. I. Clinical responses to bone blend or hip marrow grafts.

A clinical evaluation was undertaken to compare regeneration of osseous defects following implantation of either osseous coagulum-bone blend from intraoral sources or autogenous iliac marrow-cancellous bone. Thirty-two transplants were performed in 15 male patients. The intraosseous defects in which marrow was placed (initial average depth = 7.18 mm) filled 60.7% (average fill = 4.36 mm). Defects in which osseous coagulum-bone blend was placed (initial average depth 4.0 mm) filled 73% (average fill = 2.93 mm). The difference in results between the two materials was not statistically significant. Therefore, similar levels of osseous regeneration apparently took place regardless of graft material used.

Osseous autografts. II. Histological responses to osseous coagulum-bone blend grafts.

Three human intraosseous lesions were treated using osseous coagulum-bone blend as graft material. These sites were surgically removed 6 to 13 weeks after treatment and the blocks prepared for histologic analysis. Periodontal remodeling at the site of grafting was noted in all specimens. This remodeling involved the osseous walls, periodontal ligament, cementum and graft spicules. Both osteoclastic and osteoblastic activities were seen at the borders of the spicules. Exfoliation of spicules was particularly frequent in the six-week specimen. Nevertheless, regenerating of both bone and cementum was actively taking place even in this early specimen and was still evident in the older specimens. Of particular interest was the apparent marked increase in cementogenesis at the graft sites and the variations in parallel or functional orientation of the periodontal ligament in these areas. Significant functional orientation of segments of the periodontal ligament were seenin the early specimens, but not in the latter one. The reason for such variations in ligament pattern is not known at this time.

Clinical evaluation of a newly designed contoured tooth-brush.

A newly designed contoured toothbrush was tested against the Oral B toothbrush in a single blind crossover study over a 6-month period using 78 patients. The findings were: (1) The contoured toothbrush was significantly better (P less than 0.01) than the Oral B brush for gingival index scores; (2) Plaque scores were lower for the contoured brush (P = 0.10); (3) No significant differences were observed with respect to calculus scores.

Tetracyclines: double blind clinical study to evaluate the effectiveness in periodontal surgery.

Twenty consecutive hospital patients who were to have periodontal surgery were assigned to one of two groups in a double blind clinical study. Ten were placed on tetracycline 250 mg, 6 times per day for 5 days. The other ten were given an identical appearing placebo 6 times per day for 5 days. The capsules were placed in a brown envelope so that neither the patient nor the periodontist knew which medication was being administered. The patients were randomly assigned to one of the two groups and were evaluated subjectively and objectively on the 3rd day and the 7th day. Statistically there were no differences between the two groups. In both groups there was some inflammation on the 3rd day but on the 7th day, it had subsided. Tetracycline is not recommended for routine prophylactic use in periodontal surgery.

Tetracycline: a clinical study to determine its effectiveness as long-term adjuvant.

A random double blind crossover study of patients on the effects of tetracycline therapy over a 3-month period revealed that there were no significant differences between the placebo group and tetracycline-treated groups in relation to (1) Gingival Index, (2) Debris Index and (3) Papillary Bleeding. A marked improvement in the Gingival Index occurred after 3 months of treatment in each group resulting from curettage and home care. Papillary bleeding was significantly reduced after 3 months of treatment in the tetracycline group and similar trends were observed in the placebo group. The Debris Index in both experimental and placebo groups showed no significant change after treatment for 3 months. The data suggest that tetracycline therapy does not appreciably after either the Gingival Index, Debris Index, or the Papillary Bleeding Index over a 3-month period.

Periodontal healing following open debridement flap procedures. I. Clinical assessment of soft tissue and osseous repair.

The healing response of the periodontium was evaluated after periodontal flap and debridement procedures in patients with different levels of postsurgical plaque control. Thirty-one sites in 19 patients were included. Measurements were performed from a fixed reference point presurgically and before reentry surgery. All reentries were performed 24 to 28 weeks after surgery. Surgery consisted of elevating an inverse bevel mucoperiosteal flap, debriding root accretions and osseous defects, penetrating into the marrow, and suturing with interrupted sutures at or near the presurgical level. All patients were recalled at least once every 4 weeks after surgery fof professional maintenance. The number of postsurgical maintenance visits and plaque scores (NPI) before reentry were recorded for each surgical site. Average pocket depth at the 31 sites was 7.4 mm initially and 4.1 mm at the time of reentry. This reduction in pocket depth consisted of gingival recession, which averaged 2.0 mm, and a gain in attachment level, which averaged 1.4 mm. At no site was there a loss in attachment level. Average osseous depth of the 31 defects was 3.7 mm presurgically and 1.7 mm at reentry. In addition, there was an average crestal resorption of 0.8 mm and an average osseous fill of 1.2 mm. A significant positive correlation (P less than 0.001) was found between gain in attachment, osseous fill and number of postsurgical maintenance visits. A significant negative correlation was found between the amount of plaque (NPI) at the study site and both gain in soft tissue attachment and osseous fill. Multiple measurements at various points within several osseous defects revealed that osseous remodeling and fill varied significantly at different locations within the same defect.

A comparative study of ultrasonic generators and hand instruments.

A 6-month study project utilized four human subjects and a total of 63 biopsies which were obtained from gingiva treated by hand scaling, Alpha-Sonic scaling and Cavitron. These were compared with controls (untreated specimens). Microsections of soft tissues taken immediately and after 1 and 2 weeks were evaluated. The clinical acceptability of Alpha-Sonic as a working tool for periodontal scaling is to be noted.

Osseous autografts. III. Comparison of osseous coagulum-bone blend implants with open curetage.

A clinical investigation was undertaken to compare regeneration of osseous defects following either osseous coagulum-bone blend grafts or open debridement procedures. Seventy-five sites in 28 patients were treated by the two procedures. The average fill in the 37 intraosseous defects treated by graft procedures (initial average depth = 4.22 mm, S.D. 1.73) was 2.98 mm, S.D. 1.44. The average fill in the 38 intraosseous lesions treated by open debridement procedure (initial average depth = 3.03 mm, S.D.0.80) was 0.66 mm, S.D. 0.80. Statistical analysis showed a significant difference (P greater than 0.01) in fill patterns between the bone blend and open debridement responses in favor of graft treated sites. Therefore greater levels of osseous regeneration apparently took place in our cases following osseous coagulum-bone blend autogenous graft procedures than following open debridement procedures in all types of defects studies.