Risk factors for community-associated Clostridioides difficile infection in young children.

The majority of paediatric Clostridioides difficile infections (CDI) are community-associated (CA), but few data exist regarding associated risk factors. We conducted a case-control study to evaluate CA-CDI risk factors in young children. Participants were enrolled from eight US sites during October 2014-February 2016. Case-patients were defined as children aged 1-5 years with a positive C. difficile specimen collected as an outpatient or ⩽3 days of hospital admission, who had no healthcare facility admission in the prior 12 weeks and no history of CDI. Each case-patient was matched to one control. Caregivers were interviewed regarding relevant exposures. Multivariable conditional logistic regression was performed. Of 68 pairs, 44.1% were female. More case-patients than controls had a comorbidity (33.3% vs. 12.1%; P = 0.01); recent higher-risk outpatient exposures (34.9% vs. 17.7%; P = 0.03); recent antibiotic use (54.4% vs. 19.4%; P < 0.0001); or recent exposure to a household member with diarrhoea (41.3% vs. 21.5%; P = 0.04). In multivariable analysis, antibiotic exposure in the preceding 12 weeks was significantly associated with CA-CDI (adjusted matched odds ratio, 6.25; 95% CI 2.18-17.96). Improved antibiotic prescribing might reduce CA-CDI in this population. Further evaluation of the potential role of outpatient healthcare and household exposures in C. difficile transmission is needed.

Hydroxyapatite/PMMA composites as bone cements.

Currently PMMA is the polymer most commonly used as a bone cement for the fixation of total hip prostheses. Ideally, a bone cement material should be easy to handle, biologically compatible, nonsupporting of oral microbial growth, available in the particulate and molded forms, easy to obtain, nonallergenic, adaptable to a broad range of dental and medical applications, in possession of high compressive strength, and effective in guided tissue regenerative procedures. One of the problems associated with the conventional types of bone cement used is their unsatisfactory mechanical and exothermic reaction properties. The purpose of this in vitro study was to investigate and compare the mechanical properties (three-point bending strength, energy-to-break, and modulus of elasticity) and physical properties (setting time, water sorption, and exothermic heat) of HA/PMMA (HA group) and bovine-bone originated HA/PMMA (BB group) composites. Composites samples were fabricated by admixing method. It was found that the addition of HA and BB particles increased the water sorption. Generally 10 v/o 20 v/o HA and 0 v/o to 10 v/o BB ratio combinations had significant beneficial effects on the mechanical properties. The heat generated during polymerization was influenced by the different admixtures. More than 40 v/o HA and 40 v/o BB should be mixed into PMMA to reduce the peak temperature. Overall evaluation indicated that the BB group had better properties than the HA group.

The role of periodontal maintenance in dental practice.

Periodontal maintenance therapy is dependent both upon methods of disease control that are either patient or therapist applied as well as on compliance with regular recall schedules. Recent advances in the design and use of mechanical aids for plaque removal, electric toothbrush design, use of chemotherapeutic plaque control agents, and evaluations of the role of maintenance therapy in practice are included. Numerous studies indicate that compliance with recall intervals may be difficult to achieve but is essential to the success of periodontal therapy. Suggestions for approaches to effective periodontal maintenance therapy are provided.

Preventive strategies and supportive treatment.

There is a preponderance of evidence in the literature that periodontal and other oral diseases, such as caries, can be treated and controlled by thorough mechanical plaque removal by the patient, the use of antimicrobial agents and antibiotics when necessary, and participation with the therapist in a well monitored, long-range program of supportive periodontal therapy. Recent evidence suggests that the control and prevention of oral disease, especially periodontitis, is especially important for patients with various systemic conditions that can be impacted by oral infections. It is far better for patients and therapists to practice primary and even secondary prevention with effective plaque control and regular, consistent supportive periodontal therapy, than having to rely on tertiary prevention for disease that has progressed to a level that requires costly treatment, is time-consuming and carries a greater risk of morbidity.

Examining the prevalence and characteristics of abfractionlike cervical lesions in a population of U.S. veterans.

BACKGROUND: Abfraction is believed to be caused by biomechanical loading forces. It may be due to flexure and ultimate fatigue of tooth tissues that occur away from the point of occlusal loading. Other possible causes of cervical lesions include toothbrush abrasion and erosion. The purpose of this study was to investigate the characteristics and prevalence of abfraction-like lesions in a population of U.S. veterans. METHODS: The authors evaluated 103 teeth with noncarious cervical lesions in 32 subjects and characterized them based on the surface on which the lesion was located, history of toothbrush abrasion, size of the lesion, presence of plaque, surface texture, and presence and size of occlusal wear facets. RESULTS: Clinical examination revealed that adjacent control teeth had a significantly lower percentage of surfaces with plaque than did teeth with cervical lesions. Control teeth also had significantly less gingival recession than did affected teeth. Seventy-five percent of subjects reported a history of using a firm toothbrush, and 78.1 percent reported using a brushing technique that is known to cause toothbrush abrasion in the affected area. Affected teeth had neither significantly different occlusal wear facets nor occlusal contacts than control teeth. No significant correlations were found between cervical lesion dimensions and facet area. CONCLUSIONS: Toothbrush abrasion is strongly suspected as contributing to the formation of the majority of wedge-shaped lesions in this group of subjects. A small subset of lesions is thought to have resulted from some other phenomenon. Although the presence or contribution of occlusal stresses in the direct formation of these lesions could not be measured directly, the possibility of abfraction could not be eliminated. CLINICAL IMPLICATIONS: Because the existence of abfraction could not be ruled out in about 15 percent of the cases, teeth with noncarious, wedge-shaped lesions warrant careful occlusal evaluation, with the possible need for occlusal adjustment or bitesplint therapy to treat bruxism.

The effect of locally delivered controlled-release doxycycline or scaling and root planing on periodontal maintenance patients over 9 months.

BACKGROUND: This research report evaluates clinical changes resulting from local delivery of doxycycline hyclate (DH) or traditional scaling and root planing (SRP) in a group of patients undergoing supportive periodontal therapy (SPT). METHODS: In all, 141 patients received either DH (67) or SRP (74) treatment in sites > or =5 mm on one-half of their dentition at baseline and month 4. RESULTS: Clinical results were determined at month 9. Baseline mean probing depth recordings were similar between the two groups (DH = 5.9 mm; SRP = 5.9 mm). Mean month 9 results showed similar clinical results for attachment level gain (DH 0.7 mm; SRP 0.8 mm) and probing depth reduction (DH 1.3 mm; SRP 1.1 mm). Percentage of sites showing > or =2 mm attachment level gain at month 9 was 24.7% in the DH group and 21.2% in the SRP group. Thirty-nine percent (39%) of DH sites and 38% of SRP sites showed > or =2 mm probing depth reduction. When treated sides of the dentition were compared to untreated sides, DH showed a difference in disease activity (> or =2 mm attachment loss) from 19.3% (untreated) to 7.2% (treated); and SRP from 14.3% (untreated) to 8.1% (treated). CONCLUSIONS: Results show that both DH without concomitant mechanical instrumentation and SRP were equally effective as SPT in this patient group over the 9-month study period.

Effects of smoking on local delivery of controlled-release doxycycline as compared to scaling and root planing.

This paper examines the effects of smoking on the treatment outcomes of two nonsurgical therapies: (1) scaling and root planing alone (SRP) or (2) controlled-release of subgingivally delivered doxycycline hyclate in a polylactic acid based polymer gel. Subjects from 2 9-month multicenter studies were classified as nonsmokers (never smoked: 100 subjects), former smokers (137 subjects), and current smokers (> or = 10 cigarettes/day: 121 subjects). Clinical parameters were analyzed for treated sites with baseline probing depths > or = 5 mm and for a subset of treated sites with baseline probing depths of > or = 7 mm. Clinical parameters (plaque levels, clinical attachment levels, pocket depths, and bleeding on probing) were analyzed at baseline, 4, 6, and 9 months. In the doxycycline treated group in general, there were neither marked significant differences in clinical attachment gain nor differences in probing depth reduction among the 3 smoking groups. On the other hand, in the scaling and root planing treated group in general, there were significant differences in clinical attachment gain and pocket depth reduction, with non-smokers responding better than former smokers and current smokers at 6 and 9 months. These differences in clinical response between scaling and root planing alone versus controlled-release of locally-delivered doxycycline hyclate among these 3 smoking groups are discussed in relation to treatment implications for smokers.

Two multi-center studies evaluating locally delivered doxycycline hyclate, placebo control, oral hygiene, and scaling and root planing in the treatment of periodontitis.

BACKGROUND: The clinical efficacy and safety of doxycycline hyclate (8.5% w/w) delivered subgingivally in a biodegradable polymer (DH) was compared to placebo control (VC), oral hygiene (OH), and scaling and root planing (SRP) in 2 multi-center studies. METHODS: Each study entered 411 patients who demonstrated moderate to severe periodontitis. Patients had 2 or more quadrants each with a minimum of 4 qualifying pockets > or =5 mm that bled on probing. At least 2 of the pockets were > or =7 mm. Treatment with DH, VC, OH, or SRP was provided at baseline and again at month 4. Clinical parameters were recorded monthly. RESULTS: DH and SRP resulted in nearly identical clinical changes over time in both studies. Mean 9 month clinical attachment level gain (ALG) was 0.8 mm for the DH group and 0.7 mm for the SRP group in Study 1, and 0.8 mm (DH) and 0.9 mm (SRP) in Study 2. Mean probing depth (PD) reduction was 1.1 mm for the DH group and 0.9 mm for the SRP group in Study 1 and 1.3 mm for both groups in Study 2. Frequency distributions showed an ALG > or =2 mm in 29% of DH sites versus 27% of SRP sites in Study 1 and 31% of DH sites versus 34% of SRP sites in Study 2. PD reductions > or =2 mm were seen in 32% of DH sites versus 31% of SRP sites in Study 1 and 41% of DH sites versus 43% of SRP sites in Study 2. Comparisons between DH, VC, and OH treatment groups showed DH treatment to be statistically superior to VC and OH. Safety data demonstrated a benign safety profile with use of the DH product. CONCLUSIONS: Results of this trial demonstrate that treatment of periodontitis with subgingivally delivered doxycycline in a biodegradable polymer is equally effective as scaling and root planing and superior in effect to placebo control and oral hygiene in reducing the clinical signs of adult periodontitis over a 9-month period. This represents positive changes resulting from the use of subgingivally applied doxycycline as scaling and root planing was not limited regarding time of the procedure or use of local anesthesia.

Periodontal treatment for elderly patients.

The largest growing segment of our society is that of older Americans. The population explosion of older adults challenges both general practitioners and periodontists to provide the highest level of care available. More of our patients will have concurrent medical conditions that alter or modify the delivery and provision of periodontal care. This paper reviews some of the common conditions occurring in the older patient and suggests some modifications in periodontal therapy which may be beneficial. The therapist must be knowledgeable about the medications commonly used for treating the chronic diseases of the older population. Finally, the therapist must become adept in performing functional assessments of patients so that the types of therapy administered contribute to the quality of life desired by patients.

Periodontal treatment for elderly patients.

The largest growing segment of our society is that of older adults. The population explosion of older adults challenges both general practitioners and periodontists to provide the highest level of care available. More of our patients will have concurrent medical conditions that alter or modify the delivery and provision of periodontal care. This paper reviews some of the common conditions occurring in the older patient and suggests some modifications in periodontal therapy which may be beneficial. The therapist must be knowledgeable about the medications commonly used for treating the chronic diseases of the older population. Finally, the therapist must become adept in performing functional assessments of patients so that the types of therapy administered contribute to the quality of life desired by patients.

Guided tissue regeneration. Nonabsorbable barriers.

Nonabsorbable barriers are considered the material by which all other barriers are judged. They have a well-established record of safety and efficacy. They are not a panacea, however. Practitioners must take special care when selecting both patients and surgical sites for GTR. Extensive experience, superior surgical ability, and meticulous attention to detail are also required if one is to achieve predictably favorable results.

Parathyroid hormone regulates the expression of the nuclear mitotic apparatus protein in the osteoblast-like cells, ROS 17/2.8.

The parathyroid hormone (PTH) signaling pathways that effect changes in osteoblast gene expression also alter the organization of the cytoskeletal proteins. PTH regulates the expression of nucleoskeletal proteins, such as nuclear mitotic apparatus protein (NuMA) and topoisomerase II-alpha. NuMA is a structural component of the interphase nucleus and organizes the microtubules of the mitotic spindle during mitogenesis. We propose that PTH-induced alterations in osteoblast cytoarchitecture are accompanied by changes in osteoblast nuclear structure that contribute to changes in gene expression. We used immunofluorescence and confocal microscopy to determine the effect of PTH on the expression and nuclear distribution of NuMA in the rat osteosarcoma cell line, ROS 17/2.8. Cells were treated with PTH or vehicle, then fixed and stained with NuMA antibody. Optical sections of interphase naive cells revealed a diffuse distribution of NuMA, interspersed with speckles, in the central nuclear planes but not in nucleoli. During the metaphase and anaphase, NuMA localized at the mitotic spindle apparatus. The percentage of NuMA-immunopositive ROS 17/2.8 cells decreased with increasing confluence, but serum starvation did not attenuate NuMA expression. Cell density-dependent changes in cytoskeletal organization were observed in these cells. PTH treatment induced changes in cytoskeletal organization and increased the percentage of NuMA-immunopositive ROS 17/2.8 cells. These data suggest that PTH effects changes in osteoblast nuclear architecture by regulating NuMA, and that these alterations may be coupled to cytoskeletal organization.

Antimicrobials in periodontal practice.

Antimicrobial agents provide an additional means of combating the infective agents encountered in the periodontal diseases. Delivery methods include oral rinses, dentifrices, irrigation, local delivery, and systemic administration. Agents and delivery methods should be selected with the following criteria in mind: 1. The agent must be effective against the organisms present. 2. The agent must reach the desired site of action in appropriate concentration. 3. The agent must remain at the site for a sufficient period of time. When combined with a careful patient assessment and a considered diagnosis, the use of antimicrobial agents may prove to be an important adjunct in total periodontal therapy.

A histomorphometric study on the healing of class III furcations utilizing bone labelling in beagle dogs.

The dynamics of bone turnover in the furcations of teeth treated with expanded polytetrafluoroethylene (ePTFE) membranes were evaluated using multiple fluorochrome labels in 6 male beagle dogs. Loss of attachment involving the furcation area was induced in the second, third, and fourth premolar teeth using silk ligatures. The resulting defects were treated with the use of mucoperiosteal flaps for access, debridement of the defects, and placement of ePTFE membranes covering the furcations of the second and fourth premolars (experimental teeth) while the third premolar received only debridement without membrane placement (control tooth). Five fluorochrome labels were administered intravenously at timed intervals to act as markers of the osseous response. Membranes were removed at 4 weeks and all animals were terminated at 12 weeks post-membrane placement. One side of the mandible was decalcified, sectioned at 7 microns, and stained with either hematoxylin and eosin or Gomori's tri-chrome. The opposite side provided non-decalcified tissue processed as 100 microns ground sections. Using fluorescent light and point-hit evaluation, tissue in the coronal half of each specimen was classified as either labelled bone, unlabelled bone, or resorption space. In addition, microradiographs were prepared of each ground section and specimens classified as either woven bone, old lamellar bone, or new lamellar bone. No significant differences in attachment levels, or level of junctional epithelium, were observed in decalcified sections although greater remodeling activity was noted in the experimental specimens. Comparison of ground sections revealed significant differences (P < 0.05) in all categories with both methods of evaluation.(ABSTRACT TRUNCATED AT 250 WORDS)

Current epidemiologic consideration of periodontal disease.

Two interesting populations in periodontology have emerged this year. National and international reports have indicated that inflammatory periodontal disease is widespread in adolescents, although most of the cases of disease are considered to be in a reversible stage. Nevertheless, the attachment loss present portends serious future problems. The rapidly growing elderly population presents a unique problem of assessment. Current indices do not adequately evaluate recession. Thus, there is substantial underestimation of periodontal disease in the elderly. Further insight into the interrelationships between systemic diseases and local inflammatory periodontal diseases has been reported. Methods to improve statistical evaluation of site-specific periodontal data and address the shortcomings of currently available periodontal indices have been suggested. Finally, the major disadvantage of indices in treatment planning is the lack of specific treatment goals. Examples of the potentially misleading information that results from this lack were presented and the inclusion of treatment goals with treatment needs was suggested.

Clinical effects of a 0.12% chlorhexidine rinse as an adjunct to scaling and root planing.

This trial tested the adjunctive effects of a 0.12% chlorhexidine rinse (Peridex) upon gingival healing following scaling and root planing. Assessments were made on reduction in plaque (Pl), gingivitis (GI), pocket depth and gingival bleeding as measures of treatment benefit. All subjects had Class II, III or IV periodontal conditions. Following baseline examinations, subjects received a gross supragingival scaling and polishing. Subjects were separated by sex and periodontal classification, arrayed by GI scores, and randomly assigned to either the chlorhexidine rinse or a placebo rinse. Subjects were instructed to rinse with 1/2 ounce of their assigned products for 30 seconds twice daily. Following two weeks of product use, the clinical examinations were repeated and two randomly selected, opposing contralateral quadrants were scaled and root planed. After two more weeks of product use (week 4), clinical examinations were repeated and the remaining quadrants were scaled and root planed. At week 6, final clinical examinations were conducted. Since half-mouths were treated at different times and exposed to the treatment rinses for different periods, the data were analyzed for the half-mouths independently 2 and 4 weeks after gross scaling, and 2 and 4 weeks after root planing. A total of 94 subjects (47 in each treatment group) completed all phases of the trial. Gingival healing following scaling and root planing in subjects using a chlorhexidine rinse (0.12%) was significantly better than subjects using the placebo rinse as evidenced by less gingivitis (29%), fewer GI bleeding sites (48%) and less plaque (54%).

A microbiological comparison of young adults based on relative amounts of subgingival calculus.

This study compared the relative amounts of Actinobacillus actinomycetemcomitans (Aa), Eikenella corrodens (Ec), and black-pigmented anaerobic rods, and the proportions of coccoid forms, nonmotile rods, motile rods, spirochetes, and total motile organisms in subgingival plaque samples from 2 groups of young adults with generalized moderate to severe periodontitis. Two groups of 12 untreated patients were selected based on the relative amounts of subgingival calculus detected. Subgingival plaque samples (2 sites/patient) were taken with a sterile curet, dispersed, and plated under anaerobic conditions on ETSA, ETSA-kanamycin, ETSA-clindamycin, and TSBV agar. Appropriate biochemical tests were performed to confirm suspected microorganisms. Phase-contrast microscopy also was used to count the relative numbers of coccoid forms, nonmotile rods, motile rods, and spirochetes in each of the samples. Patients with no clinically detectable subgingival calculus harbored significantly greater proportions (%) of coccoid forms and Aa and greater amounts (CFU/mg) of Aa than did patients with obvious amounts of subgingival calculus. Subjects with clearly detectable subgingival calculus possessed greater proportions of motile rods, total motile organisms, and black-pigmented anaerobic rods than did subjects with little or no subgingival calculus. Young adult patients with generalized moderate to severe disease and little or no detectable subgingival calculus may possess a subgingival microbiota with relatively higher numbers of Aa and coccoid forms, and a lower percentage of BPB, motile rods, and total motile organisms as compared to similar patients with greater amounts of subgingival calculus.

Effect of zinc upon cell attachment and proliferation on periodontally-diseased root surfaces.

The purpose of this study was to determine the effect of zinc ions on fibroblast attachment to periodontally-diseased root surfaces in vitro. Extracted periodontally-diseased teeth were treated with 0.5% ZnCl2 by iontophoresis at 0.5 mA for 2 to 6 minutes. Control groups were untreated diseased and untreated healthy teeth. Sections of the root underlying the pocket were cut from the diseased teeth. The specimens were incubated for 18 hours with L929 mouse fibroblasts, then transferred and incubated in cell-free medium for 48 hours. Cell attachment was evaluated by cell counts and scanning electron microscopy (SEM). Root surfaces were sampled with an acid-etch technique and zinc was measured with an atomic absorption spectrophotometer. Two samples from each group were examined for cell attachment with SEM. Data were analyzed using the appropriate statistical methods. The results showed that diseased, untreated root surfaces had significantly fewer cells attached; however, zinc iontophoresis did not significantly improve cell attachment to the diseased root surfaces. Zinc analysis showed that diseased, untreated root surfaces had a higher zinc content than healthy ones. SEM examination showed striking differences in cell attachment to healthy versus diseased root surfaces. The data indicated that zinc iontophoresis did not significantly enhance cell attachment to root surfaces of diseased teeth.

A clinical evaluation of the Sulcabrush.

The purpose of this study was to compare the effectiveness of a unituft brush in combination with a conventional brush for plaque removal and maintenance of gingival health. Thirty patients presenting for routine dental care were examined and scored for plaque deposits and gingival inflammation. All subjects received a dental prophylaxis consisting of removal of all supragingival and subgingival deposits and polishing of the clinical crowns. Subjects were subsequently evaluated at 1 week, 6 weeks and 12 weeks. The addition of a unituft brush to the patient's regimen of oral hygiene procedures resulted in significant reductions at 12 weeks in both plaque scores (p less than .05) and gingival inflammation (p less than .01) when compared to the use of the conventional brush alone.