Early Creeping Attachment Noted after Mandibular Labial Frenuloplasty.

Recession of the mandibular central incisors is frequently associated with high frenum insertion. Often times, this recession is accompanied by a lack of sufficient amount of keratinized tissue and absence of attached gingiva. In this case report, an ASA I patient presented with Cairo Recession Type 2 (RT2) and a minimal amount of keratinized tissue on the mandibular central incisors and underwent frenuloplasty in the anterior mandible with the use of a conventional scalpel technique due to high frenum attachment. The results demonstrated creeping attachment of 1.0 mm as early as 10 days postoperatively resulting in complete root coverage and closure of the interproximal space between teeth #24 and 25. A second soft tissue surgery was avoided due to complete root coverage which remained stable at the 6-month follow-up appointment.

Role of supportive maintenance therapy on implant survival: a university-based 17 years retrospective analysis.

OBJECTIVE: The objective of this study was to determine whether professional maintenance appointments were related to a decrease on dental implant loss. METHODS: We performed a retrospective review (1995-2012) of 1020 patient dental charts to collect data including a cadre of different variables such as age, gender, race, diabetes, osteoporosis, jaw location, implant dimensions and professional maintenance therapy. As a patient may have multiple implants which are correlated, we selected one random implant per patient to assure independence of observations assumption of the Cox proportional hazards regression model. Data analysis was performed using Kaplan-Meier survival curves and multivariate analysis using Cox proportional hazards regression analysis. RESULTS: Our results demonstrate that subjects with no maintenance had the lowest cumulative survival rate as compared to subjects with regular maintenance. In a multivariate Cox regression model, regular maintenance patients had the dental implant failure rate reduced by 90% as compared to no maintenance (P = 0.001). If patients had less than one maintenance visit per year, the failure rate was reduced by 60% as compared to no maintenance, but the difference was not statistically significant (P = 0.08). CONCLUSION: From this research, we conclude that a professional administered periodontal maintenance at least on an annual basis is a critical factor for implant survival.

Assessment of the environmental fate and effects of azilsartan, a selective antagonist of angiotensin II type 1.

In this paper the results of a thorough evaluation of the environmental fate and effects of azilsartan are presented. Azilsartan medoxomil is administered as a pro-drug for the treatment of patients with essential hypertension. The pro-drug is converted by hydrolysis to the active pharmaceutical ingredient azilsartan. Laboratory tests to evaluate the environmental fate and effects of azilsartan medoxomil were conducted with azilsartan and performed in accordance with OECD test guidelines. The predicted environmental concentration (PEC) in surface water was estimated at 0.32 µg L(-1) (above the action limit of 0.01 µg L(-1)), triggering a Phase II assessment. Azilsartan is not readily biodegradable. Results of the water sediment study demonstrated significant shifting of azilsartan metabolites to sediment. Based on the equilibrium partitioning method, metabolites are unlikely to pose a risk to sediment-dwelling organisms. Ratios of the predicted environmental concentrations (PECs) to the predicted-no-effect concentrations (PNECs) did not exceed the relevant triggers, and the risk to aquatic, sewage treatment plant (STP), groundwater and sediment compartments was concluded acceptable. A terrestrial assessment was not triggered. Azilsartan poses an acceptable risk to the environment.

Citric acid demineralization and subepithelial connective tissue grafts.

BACKGROUND: The present study was designed to evaluate the effect, if any, of citric acid root demineralization in the outcome of subepithelial connective tissue grafts performed to cover localized gingival recessions. METHODS: Thirty-six patients participated, each providing one gingival recession; 19 received citric acid demineralization, while 17 did not. All were treated surgically with subepithelial connective tissue grafts and followed for 6 months. At baseline and 6 months, the following parameters were recorded: plaque index, gingival index, recession height, probing depth, recession width, and amount of keratinized tissue. Data were analyzed statistically to 1) evaluate the results achieved with each procedure individually over time and 2) compare the results obtained with the 2 procedures after 6 months. RESULTS: Results showed significant reductions in recession height after 6 months independently of whether citric acid was applied or not (2.79+/-0.79 versus 2.56+/-0.73). Similarly, recession width was significantly reduced (3.74+/-1.19 versus 3.50 +/-0.73), and the width of keratinized tissue was significantly increased (2.47+/-1.6 versus 2.3+/-1.2). No significant changes in probing depth were found (-0.16+/-0.06 versus -0.13+/-0.81). No significant differences were found when both techniques were compared in any one of the parameters analyzed (all P >0.30). CONCLUSIONS: It is concluded that: 1) the subepithelial connective tissue graft procedure provides a satisfactory solution in the treatment of localized gingival recessions, and 2) citric acid demineralization does not affect the clinical outcome of the surgical technique.

Treatment of intraosseous defects with bioabsorbable barriers alone or in combination with decalcified freeze-dried bone allograft: a randomized clinical trial.

BACKGROUND: This study clinically compares the outcomes obtained from the use of a bioabsorbable barrier device in combination with demineralized freeze-dried bone allograft (DFDBA) to the results obtained from the barrier device used alone in the treatment of human intraosseous defects. METHODS: The study consisted of 30 patients with one intraosseous periodontal defect each. The trial included defects with loss of attachment of > or = 6 mm, with a radiographically detectable defect of at least 4 mm and with at least 2 remaining osseous walls. After the hygienic phase, at baseline, probing depth (PD), clinical attachment level (CAL), and recession (REC) were measured. During open flap debridement, the defects were randomly assigned to receive either a polylactic acid (PLA) barrier in combination with DFDBA (test) or a PLA barrier alone (control). Additionally, baseline osseous intrasurgical measurements of the periodontal defect were obtained to evaluate the amount of bone regeneration. PD, CAL, and REC were remeasured at 6 and 12 months postsurgery and osseous measurements repeated at 12 months during a re-entry procedure. RESULTS: Two-sample t-test comparisons of mean PD, CAL, and REC measurements (mm) between test (PLA+DFDBA) and control (PLA alone) groups at baseline, PLA+DFDBA: PD = 7.3, CAL = 8.1, REC = -0.7; PLA-alone: PD = 7.9, CAL = 8.4, REC = -0.5, were not statistically different (P>0.05). The following mean changes (delta) at 6 months for the test and the control groups were: decreased PD = 3.6 and 4.0 mm; gain CAL = 2.7 and 3.1 mm; and increased REC = -0.8 and -0.8 mm, respectively. At 12 months the changes for the test and control groups were: decreased PD = 3.3 and 4.1 mm; gain CAL = 2.3 and 3.2 mm; and increased REC = -0.8 and -1.0 mm, respectively. Two-sample t-test comparisons between PD, CAL, and REC changes yielded no significant differences between treatments (P > 0.05), except for the change in CAL at 12 months in favor of the control group, P = 0.008. Comparisons of osseous measurements resulted in no significant differences between groups at baseline and at 12 months (P > 0.05). The intrabony defect filled on the average 3.72 mm for the test and 4.85 mm for the control group. The experimental defects showed a 4.73 mm defect depth reduction, while the control defects reduced 5.35 mm. Re-entry measurements of osseous crest resorption were 1.1 mm for the test and 0.61 mm for the control. CONCLUSIONS: In the intraosseous defects treated in this study, the addition of DFDBA to the GTR procedure did not significantly enhance the clinical results obtained with the GTR procedure alone.

Effects of expanded polytetrafluoroethylene and polylactic acid barriers on healthy sites.

The configuration of the barrier devices to treat interproximal defects by guided tissue regeneration (GTR) necessitates inclusion of healthy adjacent teeth to secure the barriers in place. The purpose of this study was to evaluate the effects of expanded polytetrafluoroethylene (ePTFE) and polylactic acid (PLA) barrier devices on probing depth (PD), clinical attachment level (CAL), and crestal bone height in healthy sites. The study included 30 patients who were in an earlier study which compared the effects of GTR utilizing an ePTFE or a PLA barrier in intrabony defects. Thirty defects were randomly assigned to receive either a PLA (test) or an ePTFE barrier (control) after open flap debridement. The sites in this investigation included those healthy sites in the immediately adjacent non-affected teeth covered by the barriers. CAL and PD were measured at baseline and 12 months. Intrasurgical crestal bone height was recorded at the time of barrier placement and at a 12-month re-entry. Two-sample t-test comparisons of PD and CAL measurements between barrier device covered sites at baseline (PD: ePTFE, 2.32+/-0.51; PLA, 2.59+/-0.74; CAL: ePTFE, 2.71+/-0.66; PLA, 2.59+/-0.65 mm), and at one year (PD: ePTFE, 2.14+/-0.37; PLA, 2.07+/-0.56; CAL: ePTFE, 3.14+/-1.05; PLA, 2.75+/-0.73 mm) were not statistically different (P > 0.05). Paired t-test was utilized to compare changes in PD, CAL, and crestal bone height from baseline to 12 months. A statistically significant reduction in PD was found in the PLA group (delta = -0.52, P = 0.01) while no significant change was found in the ePTFE group (delta = -0.18, P = 0.18). Change in CAL was statistically significant in the ePTFE group (delta = 0.43, P = 0.02) while no significant change was found in the PLA group (delta = 0.16, P = 0.39). Crestal bone height changes from baseline to 12 months were statistically different for both groups (ePTFE, delta = 0.8 mm, P = 0.001; PLA, delta = 0.6 mm, P = 0.001). These resorptive changes, when compared between treatment groups were not statistically different (P > 0.05). In conclusion, the placement of ePTFE or PLA barriers on healthy sites resulted in probing depth reductions and loss of attachment of 0.5 mm or less. Additionally, both groups exhibited less than 1.0 mm of crestal bone resorption.

Assessment of guided tissue regeneration procedures in intrabony defects with bioabsorbable and non-resorbable barriers.

THE PURPOSE OF THIS STUDY was to assess periodontal regenerative techniques in intrabony defects utilizing a bioabsorbable, polylactic acid (PLA) barrier or the non-resorbable, expanded polytetrafluoroethylene (ePTFE) barrier. Thirty patients (26 to 64 years old) each with one radiographically evident intrabony periodontal lesion of probing depth > or = 6 mm participated in a 12-month controlled clinical trial. The subjects were randomly divided into two independent groups. The test group (n = 16) received a PLA barrier. The control group (n = 14) received an ePTFE barrier. Plaque index (PI), gingival index (GI), probing depth (PD), clinical attachment level (CAL), and bone fill were recorded by a single calibrated examiner not involved with the surgical treatment prior to surgery, and at 6, 9, and 12 months postsurgery. The treatment results were statistically analyzed utilizing two sets of data. The "averaged-site" data set consisted of values computed from the averaging of measurements from all sites encompassing the defect. The second data set was comprised of only the deepest measurement of the defect. Statistical tests used to analyze these data sets included the t-test and paired t-test for parametric data and the Wilcoxon rank sum test and the Wilcoxon signed rank test for non-parametric data. Analyses with both the averaged-site data and deepest-site data resulted in significant improvements in PD reductions, CAL, and bone fill, after 12 months of healing with both the PLA and ePTFE barrier devices. Comparisons of healing response between treatments found no significant differences when the averaged-site data were analyzed. When only the deepest site of the defect was considered, the control group resulted in significantly more attachment gain (ePTFE, 3.36 mm; PLA, 1.75 mm; P < 0.02) and shallower probing depths (ePTFE, 3.29 mm; PLA, 4.69 mm; P < 0.01) than the test group. In intrabony defects, the use of PLA or ePTFE barriers in GTR procedures yielded comparable clinical results; however, in this study, data analysis using the deepest site of the defect found, after 12 months of healing, significantly more attachment gain and shallower probing depths with ePTFE.

Guided tissue regeneration. A status report for the American Journal of Dentistry.

This report reviews clinical results which have been obtained with guided tissue regeneration (GTR) using non-resorbable and resorbable materials. The report highlights the clinical factors that affect and that should be considered in order to improve the predictability of the results obtained after GTR. The indications for GTR procedures are reviewed and the surgical technique is described. The importance of periodontal maintenance, and the significance of adjunctive therapies in GTR procedures are also discussed. Based upon the vast scientific information and clinical experience with GTR, it can be stated that with the use of either resorbable or non-resorbable materials a new attachment, determined both clinically and histologically, will be promoted providing that the principles of GTR are properly implemented.

Treatment of a patient with hereditary gingival fibromatosis: a case report.

A case of hereditary gingival fibromatosis is presented. Treatment consisted of apically positioned flap surgery and CO2 laser evaporation. Diagnostic and treatment issues are discussed.

The role of turns in the structure of an alpha-helical protein.

The turns joining segments of secondary structure have been proposed to be key elements in dictating the folded structures of native proteins. An alternative view assumes that turns play a passive role and are merely default structures that occur as a consequence of interactions between antiparallel segments of secondary structure, with chain reversal being dictated by the context surrounding the turn and not by the sequence of the turn itself. The solvent-exposure of turns and their tolerance to evolutionary variance suggests that they may have little or no effect on the formation of native structures. Previous investigations have focused on various types of beta-turns that connect antiparallel beta-strands with comparatively little reported on the structural role of interhelical turns. Here we probe the structural importance of such a turn in an antiparallel 4-helix bundle by randomly substituting an interhelical tripeptide in cytochrome b-562 with many different amino-acid sequences. Thirty-one of the resulting substituted proteins were characterized and all of them were shown to fold into stable, native-like structures. These results suggest that this interhelical turn does not does not play a dominant role in determining the folded structure of this antiparallel 4-helix bundle.

Power drills to fenestrate exposed bone to stimulate wound healing.

Power drills can be used to stimulate the formation of granulation tissue over exposed cortical bone. These tools allow for the rapid fenestration and selective abrasion of large areas of exposed bone; fenestration and abrasion create the multiple bleeding points essential for the production of granulation tissue. The granulation tissue thus produced is allowed to grow out through the holes to cover bone. This procedure can be performed in an outpatient setting, usually without the need for either local or general anesthesia; it is particularly useful for patients considered to be poor risks for general anesthesia. Healing by granulation tissue is a somewhat slow process, but it has a high success rate, causes few complications, and produces very good cosmetic results. Two cases illustrate the method of fenestration of exposed cranial bone to stimulate granulation tissue. Specific instructions describe the needed care of exposed bone.

Subchronic toxicity studies in dogs and in utero rats fed diets containing Bacillus stearothermophilus alpha-amylase from a natural or recombinant DNA host.

Beagle dogs and Fischer 344 rats were fed diets containing 0, 36 or 72 units Bacillus stearothermophilus alpha-amylase (Bsa)/g food or of Bacillus subtilis alpha-amylase (cBsa)/g food. The dogs (four/sex/group) received treated diets for 13 wk. For the rat studies, the parental (F0) generation (12 males and 24 females/group for the Bsa study, and 26 rats/sex/group for the cBsa study) received treated diets for 13 or 4 wk, respectively, before breeding and through weaning of the F1 pups; 20 F1 rats/sex/group received treated diets for at least 13 wk (from weaning until necropsy). There were no treatment-related antemortem observations, reproductive effects or ophthalmic, haematological, macroscopic or microscopic findings in treated dogs or rats, and no differences were noted in body weights for dogs or parental rats. Mean body weights of F1 pups from F0 rats exposed to 72 units cBsa/g were significantly lower than those of the control animals on lactation day 28. This effect may have been related to the slight reduction in body weights and significant reduction in food consumption (gestation days 14-20) of the F0 dams. However, this did not continue into the growth phase for the F1 generation. In the Bsa studies, there were no treatment-related effects in clinical pathology values, and organ-weight data did not correlate with macroscopic or microscopic findings. Male dogs given cBsa had significantly lower albumin (36 units/g), calcium (36 and 72 units/g) and inorganic phosphorus (72 units/g) values compared with those of the control males; there were no treatment-related changes in blood chemistry values in rats. Based on the results of these studies, the no-observable-effect level for alpha-amylase fed to dogs or rats is 36 units/g food.

Disseminated lupus vulgaris presenting as granulomatous folliculitis.

A 69-year-old man presented with a 3-year history of scattered, grouped, asymptomatic follicular papules, pustules, and nodules tending toward coalescence into large geographic aggregates. Repeated cutaneous biopsy specimens showed granulomatous folliculitis with negative Ziehl-Neelsen stains. Finally, biopsy material submitted for mycobacterial culture grew Mycobacterium tuberculosis. No evidence of active systemic tuberculosis was found. The patient had a very rare form of tuberculosis, disseminated lupus vulgaris, presenting with granulomatous folliculitis, which is usually not seen in lupus vulgaris. The lesions resolved after an 18-month course of isoniazid and rifampin. The unusual clinical and histologic presentation as well as occasional partial remissions following a variety of nonspecific empiric therapies delayed diagnosis despite multiple evaluations. This case illustrates the importance of obtaining mycobacterial cultures from skin biopsy specimens in addition to special stains whenever cutaneous tuberculosis is suspected.

Subchronic toxicity studies in dogs and in utero-exposed rats fed diets containing Bacillus megaterium amylase derived from a recombinant DNA organism.

Subchronic toxicity studies were performed using a food-grade enzyme product from a recombinant Bacillus subtilis containing the B. megaterium amylase gene. Beagle dogs (four/sex/group) and Fischer 344 rats (25/sex/group) were fed diets containing 0, 20, 60 or 100 units amylase/g food. The dogs received treated diets for 13 wk. The parental (F0) rats received treated diets for 4 wk before breeding and through weaning of the F1 pups; 25 F1 rats/sex/group received treated diets for at least 13 wk (from weaning until necropsy). All animals appeared healthy throughout the studies. Treated animals had sporadic significant differences in body weight and food consumption values when compared with those of controls, but they were not considered toxicologically meaningful. There were no treatment-related effects on reproduction indices, growth variables or litter data in rats. There were no changes in clinical pathology values, organ weights or macroscopic and microscopic observations that were related to treatment. Based on the results of this study, the no-observable-effect level for this amylase fed to dogs or rats is no less than 100 units/g food. This is 6000-12,700 times the predicted human use level.

Importance of complete cutaneous examination for the detection of malignant melanoma.

With the rate of melanoma increasing 1,000% in the past 50 years, the early detection of the disease is becoming more important. Data from 2,239 persons seen at the Manhattan Melanoma/Skin Cancer Detection Screening Program were analyzed to determine if a complete cutaneous examination would significantly increase the chance of detecting melanoma. Thirteen of the fourteen melanomas detected were on anatomic sites normally covered by clothing. Patients having complete skin examinations were 6.4 times more likely to have a melanoma detected than those having partial examinations (p = 0.025). These findings reinforce the importance of complete skin examination for the early detection of malignant melanoma.

Polychlorinated biphenyl induction of hepatocellular carcinoma in the Sprague-Dawley rat.

Male and female Sprague-Dawley rats (70 males and 70 females in the initial group) were fed a diet containing a polychlorinated biphenyl mixture (Aroclor 1260, 100 ppm for 16 months and 50 ppm for an additional 8 months) for 2 years followed by a control diet for 5 months. A control group initially consisted of 63 males and 63 females. Sequential morphologic changes were evaluated throughout the study. In the PCB-exposed group the following hepatocellular lesions developed in sequence: centrolobular cell hypertrophy at 1 month, foci of cell alteration at 3 months, areas at 6 months, neoplastic nodules at 12 months, trabecular carcinoma at 15 months, and adenocarcinoma at 24 months. In addition, simple and cystic cholangioma at 18 and 23 months, respectively, and adenofibrosis at 22 months were present. With the exception of hepatocyte hypertrophy and adenofibrosis, all lesions contained cells that were positive for gamma glutamyl transpeptidase activity. In the PCB-exposed group that was examined after 18 months, hepatocellular neoplasms were present in 95% of the 47 females and in 15% of the 46 males. Distant organ metastases did not occur and the mortality rate was not increased in the PCB exposed group. In 81 control rats examined after the 18th month, only 1 hepatocellular neoplasm (a neoplastic nodule) occurred. PCB- exposed and control rats developed simple cholangioma, cystic cholangioma and adenofibrosis; the incidence of each was greater in the PCB group. Thus, within the Sprague-Dawley rat group exposed to a diet with relatively high concentrations of Aroclor 1260 for 2 years a hepatocarcinogenic effect manifested by formation of slowly growing hepatocellular carcinomas was produced.

Toxicity studies on the radioprotective agent WR-2721 in CDF1 mice and beagle dogs.

WR-2721, S-2-(3-aminopropylamino)ethylphosphorothioic acid, is used extensively to protect normal cells during the irradiation of neoplastic cells. Dose levels for human radiotherapy are based on results obtained from laboratory animal lethality and toxicity studies. WR-2721 was administered intravenously to CDF1 mice and beagle dogs. Single dose lethality studies in mice showed the average 1/10 of the lethal dose, the median lethal dose and 9/10 the lethal dose to be 508 (1523 mg/m2), 589 (1766 mg/m2), and 682 mg/kg (2047 mg/m2), respectively. The lethal dose for female mice was lower than that for males. The 1/10 lethal dose in mice was slightly toxic to dogs; 1/10 of that dose was nontoxic. The lethal dose for dogs (6000 mg/m2) was higher than that for mice (2000 mg/m2). Clinical signs of toxicosis in the single-dose mouse toxicity study were evident in the 1st week following treatment and declined during the recovery period; signs of toxicosis were transient in dogs. Acute drug-induced pathologic changes included elevated BUN and SGOT levels, lymphoid necrosis, and renal tubular degeneration in mice. These changes were evident in the 1st week following treatment, but had dissipated by study termination. Generalized vascular changes (congestion, hemorrhage, and edema) and renal tubular degeneration occurred in treated dogs that had died or were killed moribund 7 days postinjection. These findings indicate sex-dependent and interspecies variation in the toxicity of WR-2721 with acute, but reversible, pathologic changes.