bluuebunny/crossref_metadata_2025 huggingface dataset:
Characteristics of 32 Supercentenarians
Authors: Schoenhofen Emily A. , Wyszynski Diego F. , Andersen Stacy , Pennington JaeMi , Young Robert , Terry Dellara F. , Perls Thomas T.
Published: July 2006

OBJECTIVES: To report phenotypic characteristics of 32 age‐validated supercentenarians.

DESIGN: Case series.

SETTING: U.S.‐based recruitment effort.

PARTICIPANTS: Thirty‐two supercentenarians.

MEASUREMENTS: Multiple forms of proof were used to validate age claims. Sociodemographic, activities of daily living, and medical history data were collected.

RESULTS: Age range was 110 to 119. Fifty‐nine percent had Barthel Index scores in the partially to totally dependent range, whereas 41% required minimal assistance or were independent. Few subjects had a history of clinically evident vascular‐related diseases, including myocardial infarction (n=2, 6%) and stroke (n=4, 13%). Twenty‐two percent (n=7) were taking medications for hypertension. Twenty‐five percent (n=8) had a history of cancer (all cured). Diabetes mellitus (n=1, 3%) and Parkinson's disease (n=1, 3%) were rare. Osteoporosis (n=14, 44%) and cataract history (n=28, 88%) were common.

CONCLUSION: Data collected thus far suggest that supercentenarians markedly delay and even escape clinical expression of vascular disease toward the end of their exceptionally long lives. A surprisingly substantial proportion of these individuals were still functionally independent or required minimal assistance.
Age and the Risk of Warfarin‐Associated Hemorrhage: The Anticoagulation and Risk Factors In Atrial Fibrillation Study
Authors: Fang Margaret C. , Go Alan S. , Hylek Elaine M. , Chang Yuchiao , Henault Lori E. , Jensvold Nancy G. , Singer Daniel E.
Published: July 2006

OBJECTIVES: To assess whether older age is independently associated with hemorrhage risk in patients with atrial fibrillation, whether or not they are taking warfarin therapy.

DESIGN: Cohort study.

SETTING: Integrated healthcare delivery system.

PARTICIPANTS: Thirteen thousand five hundred fifty‐nine adults with nonvalvular atrial fibrillation.

MEASUREMENTS: Patient data were collected from automated clinical and administrative databases using previously validated search algorithms. Medical charts were reviewed from patients hospitalized were for major hemorrhage (intracranial, fatal, requiring ≥2 units of transfused blood, or involving a critical anatomic site). Age was categorized into four categories (<60, 60–69, 70–79, and ≥80), and multivariable Poisson regression was used to assess whether major hemorrhage rates increased with age, stratified by warfarin use and adjusted for other clinical risk factors for hemorrhage.

RESULTS: A total of 170 major hemorrhages were identified during 15,300 person‐years of warfarin therapy and 162 major hemorrhages during 15,530 person‐years off warfarin therapy. Hemorrhage rates rose with older age, with an average increase in hemorrhage rate of 1.2 (95% confidence interval (CI) 1.0–1.4) per older age category in patients taking warfarin and 1.5 (95% CI=1.3–1.8) in those not taking warfarin. Intracranial hemorrhage rates were significantly higher in those aged 80 and older (adjusted rate ratio=1.8, 95% CI=1.1–3.1 for those taking warfarin, adjusted rate ratio=4.7, 95% CI=2.4–9.2 for those not taking warfarin) than in those younger than 80.

CONCLUSION: Older age increases the risk of major hemorrhage, particularly intracranial hemorrhage, in patients with atrial fibrillation, whether or not they are taking warfarin. Hemorrhage rates were generally comparable with those reported in previous randomized trials, indicating that carefully monitored warfarin therapy can be used with reasonable safety in older patients.
Predicting the Risk of Hospital Admission in Older Persons—Validation of a Brief Self‐Administered Questionnaire in Three European Countries
Authors: Wagner Jan T. , Bachmann Lucas M. , Boult Chad , Harari Danielle , Von Renteln‐Kruse Wolfgang , Egger Matthias , Beck John C. , Stuck Andreas E.
Published: July 2006

OBJECTIVES: To validate the Probability of Repeated Admission (Pra) questionnaire, a widely used self‐administered tool for predicting future healthcare use in older persons, in three European healthcare systems.

DESIGN: Prospective study with 1‐year follow‐up.

SETTING: Hamburg, Germany; London, United Kingdom; Canton of Solothurn, Switzerland.

PARTICIPANTS: Nine thousand seven hundred thirteen independently living community‐dwelling people aged 65 and older.

MEASUREMENTS: Self‐administered eight‐item Pra questionnaire at baseline. Self‐reported number of hospital admissions and physician visits during 1 year of follow‐up.

RESULTS: In the combined sample, areas under the receiver operating characteristic curves (AUCs) were 0.64 (95% confidence interval (CI)=0.62–0.66) for the prediction of one or more hospital admissions and 0.68 (95% CI=0.66–0.69) for the prediction of more than six physician visits during the following year. AUCs were similar between sites. In comparison, prediction models based on a person's age and sex alone exhibited poor predictive validity (AUC ≦ 0.57). High‐risk individuals (Pra score ≧ 0.5) were 2.3 times as likely (95% CI=2.1–2.6) as low‐risk individuals to have a hospital admission, and 2.1 times as likely (95% CI=2.0–2.2) to have more than six physician visits.

CONCLUSION: The Pra instrument exhibits good validity for predicting future health service use on a population level in different healthcare settings. Administrative data have shown similar predictive validity, but in practice, such data are often not available. The Pra is likely of high interest to governments and health insurance companies worldwide as a basis for programs aimed at health risk management in older persons.
Patterns and Predictors of Home Health and Hospice Use by Older Adults with Cancer
Authors: Locher Julie L. , Kilgore Meredith L. , Morrisey Michael A. , Ritchie Christine S.
Published: July 2006

OBJECTIVES: To describe patterns of home health and hospice use by older cancer patients and a comparison group of older persons without cancer. To identify predictors of home care and hospice utilization.

DESIGN: Retrospective analysis using the Surveillance, Epidemiology and End Results (SEER)‐Medicare Database, a linkage of the SEER Program of the National Cancer Institute (an epidemiological surveillance system of population‐based tumor registries) and Medicare Claims.

SETTING: The SEER data used in this paper cover a service area that includes approximately 14% of the U.S. population, including the states of Connecticut, Hawaii, Iowa, and New Mexico and the metropolitan areas of Detroit, San Francisco–Oakland, Atlanta, Seattle–Puget Sound, Los Angeles County, and San Jose–Monterey.

PARTICIPANTS: Five analytical samples were drawn. The first consisted of all cases with a diagnosis of cancer in 1997 to 1999 who were eligible for services in calendar year 1999 (n=120,072). The second and third were subsamples of these and consisted of cases with a new cancer diagnosis in 1999 (n=46,373) and cases who died in 1999 (n=41,483). The fourth consisted of a comparison sample without cancer (n=160,707). The fifth was a subsample of this and consisted of those who died in 1999 (n=6,639).

MEASUREMENTS: Utilization rates of home health and hospice services.

RESULTS: Twenty‐nine percent of cancer patients used home health services, and 10.7% used hospice services, compared with 7.8% of noncancer patients who used home health and less than 1% who used hospice. Half (51.4%) of cancer patients who used home health did not have cancer listed as an admitting diagnosis for the use of those services. Home health utilization was lowest for unmarried men.

CONCLUSION: This is the first study to evaluate community‐based home health and hospice utilization by older cancer patients. Future studies must begin to address what constitutes appropriate utilization.
Ethnic Differences in Expectations for Aging Among Older Adults
Authors: Sarkisian Catherine A. , Shunkwiler Sara M. , Aguilar Iris , Moore Alison A.
Published: July 2006

Age‐expectations of 611 non‐Latino white, African‐American, and Latino seniors recruited at 14 community‐based senior centers in the greater Los Angeles region were compared. Participants completed the Expectations Regarding Aging (ERA‐38) Survey, a self‐administered instrument with previously demonstrated reliability and validity for measuring age‐expectations. Analysis of variance was used to compare unadjusted differences between scores across ethnic groups. To examine whether observed differences persisted after adjusting for health and sociodemographic characteristics, a series of linear regression models was constructed, with the dependent variable being total ERA‐38 score and the primary independent variables being African‐American and Latino ethnicity (reference group=white), adjusting for age, sex, physical and mental health‐related quality of life (HRQoL), medical comorbidity, activity of daily living (ADL) impairments, depression, and education. Latinos had significantly lower overall age‐expectations than non‐Latino whites or African Americans after adjusting for age and sex (parameter estimate=−3.4, P=.01); this difference persisted after adjusting for health variables including medical comorbidity, HRQoL, ADL impairments, and depression. After adjusting for education, being Latino was no longer significantly associated with lower age‐expectations (parameter estimate=−1.9, P=.18). Being African American was not significantly associated with age‐expectations in any of the adjusted models. Younger age and better HRQoL were associated with higher age‐expectations in all models. In conclusion, of these 611 older adults recruited at senior centers in the greater Los Angeles region, Latinos had significantly lower age‐expectations than non‐Latino whites and African Americans, even after adjusting for health characteristics, but differences in educational levels explained this difference.
A Multidisciplinary Program for Delivering Primary Care to the Underserved Urban Homebound: Looking Back, Moving Forward
Authors: Smith Kristofer L. , Ornstein Katherine , Soriano Theresa , Muller David , Boal Jeremy
Published: July 2006

The coming decades will see a dramatic rise in the number of homebound adults. These individuals will have multiple medical conditions requiring a team of caregivers to provide adequate care. Home‐based primary care (HBPC) programs can coordinate and provide such multidisciplinary care. Traditionally, though, HBPC programs have been small because there has been little institutional support for growth.

Three residents developed the Mount Sinai Visiting Doctors (MSVD) program in 1995 to provide multidisciplinary care to homebound patients in East Harlem, New York. Over the past 10 years, the program has grown substantially to 12 primary care providers serving more than 1,000 patients per year. The program has met many of its original goals, such as helping patients to live and die at home, decreasing caregiver burden, creating a home‐based primary care training experience, and becoming a research leader.

These successes and growth have been the result of careful attention to providing high‐quality care, obtaining hospital support through the demonstration of an overall positive cost–benefit profile, and securing departmental and medical school support by shouldering significant teaching responsibilities. The following article will detail the development of the program and the current provision of services. The MSVD experience offers a model of growth for faculty and institutions interested in starting or expanding a HBPC program.
The Effect of Die Spacer on Retention and Fitting of Complete Cast Crowns
Authors: Olivera Anna Belsuzarri , Saito Tetsuo
Published: July 2006

Purpose: This study evaluated the effect of die spacer on the fit and retention of complete cast crowns by using three different cements.

Materials and Methods: Standardized full crown restoration preparations were completed on 99 extracted molar teeth, impressions were made with poly(vinyl siloxane), and stone dies were made. Dies were covered with four layers of die spacer using three techniques: (1) covering the occlusal and 1/3 of the axial surfaces, (2) covering the occlusal and 2/3 of the axial surfaces, and (3) covering the entire preparation except the apical 0.5 mm of the preparation. Complete metal crowns were cast using Pors‐on 4 alloy. Crowns were then assigned to one of three luting agent groups: resin modified glass ionomer cement, resin cement, or zinc phosphate cement. The castings were placed on their respective teeth and the marginal opening was recorded by two methods: 72 specimens were examined before and after cementation using optical microscopy with 0.001 mm resolution, and 27 specimens were examined after cementation with scanning electron microscopy. After cementation, the teeth were thermocycled for 700 cycles between 5°C and 55°C. The tensile retentive strength was measured on a universal testing machine with a crosshead speed of 0.5 mm/min. The data obtained for the fitting were recorded in millimeters and the data for the tensile retentive strength were recorded in KgF. The statistical analysis was performed by analysis of variance and post hoc Tukey's test (p< 0.05).

Results: Before cementation, better marginal fit was obtained when the die spacer covered all but the area 0.5 mm short of the margin of the preparation; however, after cementation, the resin modified glass ionomer cement group had the best fit with the same application of die spacer. Castings luted with resin cement required the greatest tensile force to produce cement failure.

Conclusions: Increasing the area of the die surface covered with spacer improved the fit of the cast restoration. After cementation, the resin modified glass ionomer showed better adaptation; however, the optical microscopy and scanning microscopy correlate well. Resin cement had the highest resistance to tensile forces.
A 4‐Year Prospective Study to Assess Peri‐Implant Hard and Soft Tissues Adjacent to Titanium Versus Gold‐Alloy Abutments in Cemented Single Implant Crowns
Authors: Vigolo Paolo , Givani Andrea , Majzoub Zeina , Cordioli Giampiero
Published: July 2006

Purpose: The purpose of this prospective clinical study was to compare titanium and gold‐alloy abutments when used with cemented, implant‐supported single‐tooth crowns. For 4 years following prosthodontic rehabilitation, these abutments were evaluated with respect to peri‐implant marginal bone levels and peri‐implant soft tissue parameters.

Materials and Methods: During the years 1998 to 2000, 20 patients were selected from a patient population receiving treatment in the Implantology Department at the University of Padova, Italy. They all presented with single‐tooth bilateral edentulous sites in the premolar/molar region with adequate bone width, similar bone height on each side, and an occlusal scheme that allowed for the establishment of identical occlusal cusp/fossa contacts on each side. Each subject received two identical implants (one in each edentulous site). One was randomly selected to be restored with a titanium abutment and a cemented implant‐supported single‐tooth crown, and the other was restored with a gold‐alloy abutment and a cemented implant‐supported single tooth crown. Data on peri‐implant marginal bone levels and soft tissue parameters were collected for 4 years after abutment and crown insertion placement and analyzed to determine whether there was a significant (p< .001) difference with respect to the type of abutments (titanium vs. gold alloy) used.

Results: All subjects completed the study. All 40 implants survived, resulting in a cumulative implant success rate of 100%. Statistical analysis revealed no significant differences between the two groups with respect to peri‐implant marginal bone levels and soft tissue parameters.

Conclusions: Within the limitations of this study, the results indicate that there was no evidence of different response with the peri‐implant marginal bone and soft tissue when titanium or gold‐alloy abutments were used in conjunction with the cemented, single‐tooth implant restorations provided for this limited patient population. There was no evidence of different behavior of peri‐implant marginal bone and of peri‐implant soft tissue when titanium abutments or gold‐alloy abutments were used for cemented single‐tooth implant restorations in this limited patient population.
Assessment of Bias in Methodology for Randomized Controlled Trials Published on Implant Dentistry
Authors: Dumbrigue Herman B. , Al‐Bayat Manal I. , Ng Clarisse C. H. , Wakefield Charles W.
Published: July 2006

Purpose: The purpose of this study was to assess randomized controlled trials (RCTs) published on implant dentistry over a 10‐year period (1991 to 2000), based on the reporting of control of potential sources of bias in the design methodology.

Materials and Methods: A MEDLINE search was conducted for RCTs using keywords dental implant and publication type randomized controlled trial. Three areas of trial methodology were assessed: (1) adequate reporting of randomization procedure, (2) blinding in assessment of outcomes, and (3) handling of subject withdrawals in data analysis. A score of 1 or 0 was assigned for each of the three potential sources of bias. Thus, the maximum quality score for an RCT is 3 and the minimum is 0.

Results: Forty‐three articles met criteria for classification as RCTs. Method of randomization was explicit in 51% of the RCTs, but only 12% incorporated blinding in the assessment of outcome. Ninety‐eight percent accounted for all subjects at the end of the study. Looking at overall quality scores, only 2% of RCTs adequately reported on control of bias in the three areas examined, 56% were deficient in one area, and 42% were deficient in two areas.

Conclusion: Reporting of randomization procedures and blinding in outcomes assessment for most implant RCTs was inadequate. Subject retention and documentation of subject withdrawals were adequately reported.
Undergraduate clinical orthodontic experience: a discussion paper
Authors: Oliver R. , Hingston E.
Published: June 2006

Abstract  Undergraduate clinical orthodontic experience may be expressed in a variety of ways. The most common way (used, inter alia, in the DentEd school visits) is by number of curriculum hours. Other ways include the number of patients seen, or number of procedures carried out. Whilst any of these methods may allow comparison between cohorts of students within a school or between schools, none of them are suitable to determine how much experience is ‘satisfactory’, nor do they indicate what the student should know, understand, or be able to do, to be considered ‘satisfactory’, and hence fit to graduate. This situation may be addressed by the use of competences and/or learning outcomes, and in 2004 the Association for Dental Education in Europe (ADEE) adopted a document that contained one major competence and five supporting competences in orthodontics. This paper considers the shortcomings of conventional methods of recording orthodontic experience in relation to the acquisition of these competences, and some ways in which staff and students may assess competence.
A comparison of the visual and technical assessment of preparations made by dental students
Authors: Esser C. , Kerschbaum T. , Winkelmann V. , Krage T. , Faber F.‐J.
Published: June 2006

Abstract  The preparation of acrylic teeth in a simulated clinical environment (phantom head) plays an essential role in pre‐clinical dental education where evaluation is performed visually by instructors. The aim of this investigation was to verify the quality criteria of a tooth preparation for a metal‐ceramic crown (tooth No. 21) with the help of digital measurement. Thirty‐six acrylic teeth were prepared by students and one tooth was prepared ideally by a trained dentist: These were examined and compared. Five experienced instructors independently assessed the quality criteria with the use of a criterion list. Afterwards, the teeth were scanned with the 3D‐laser scanner ‘es1’ (Etkon Company, Munich, Germany). The calculation of the correlation coefficient demonstrated a satisfactory correlation between visual and digital rating concerning convergence angle, shoulder width and occlusal reduction. Greater differences between experimental groups were observed with regards to other criteria on the applied criterion list. A directed calibration of the evaluators and a re‐evaluation of some measurements would be necessary to gain more precise results.
The bacteriology of the gingival crevices of erupting human incisors
Authors: Lindhe Jan , Mårnsson Ulla
Published: July 2006

The bacteriology of gingival crevices around erupting human incisors was studied with a technique described by Bervell (1960, 1964). 134 out of 196 samples gave growth in Trypticase Soy Broth and 37 out of 68 showed growth in NIH Thioglycollate Broth. A new technique was also used to obtain samples of any bacteria in the apical parts of the gingival crevices of erupting teeth. Iodine varnish was painted over the tooth and gingivae. An incision was then made with a small sterile scalpel, through the varnish membrane and the attached gingiva at right angles to the long axis of the tooth. A sterile steel blade was inserted through the incision to contact the enamel at the apical third of the gingival crevice. When this method was adapted, 24 out of 25 samples showed no growth in Trypticase Soy Broth. This result indicates that the technique avoids contamination from debris at the gingival margin or in the coronal part of the crevice. It should therefore, be of considerable value for studying the microbiota in the deeper parts of pathological pocket.
Local factors of resistance in the gingival area
Authors: Brandtzaeg Per
Published: July 2006

The local resistance factors of the gingival area are divided into two groups: (1) Physical and biochemical factors; (2) Immunologic and phagocytic activities. The status of the gingival epithelium and connective tissue may be important for the penetrability of the gingival area to bacteria and their products. The gingival pocket fluid and the saliva may be of significance in local resistance both through mechanical rinsing effects and the presence of antibacterial substances such as lysozyme. The oral microbiota by itself contributes to local resistance by bacterial antagonism. A local immune response apparently occurs in the gingiva during the development of periodontitis. The products of this response most likely include antibodies active against components and metabolites of the gingival bacteria. These antibodies may exert protective functions within the tissue as well as in the gingival pocket fluid and the saliva. Moreover, the milieu within the tissue and in the two fluids may promote phagocytosis. The inflammatory response and the possibility of hypersensitivity reactions in the gingiva are discussed in relation to local resistance.
The vascular supply of the periodontal membrane
Authors: Birn H.
Published: July 2006

The blood supply to the periodontal membrane of 84 human tooth sockets was studied by determining the number and size of the perforations in the alveolar wall. A special impression and duplication technique was used to produce a relief of the alveolar wall. This was next drawn on paper in a stereo‐microscope. By means of the measure‐and‐weigh method, calculations were made of the number and size of perforations per unit surface area in different regions of each alveolus and in different alveoli, and of the number of perforations per sq. mm. After it had been demonstrated that, in the rat, correlation existed in the alveolar wall between both the number and the size of perforations and the vessels that they carry, the size and the number of perforations were taken as a measure of the blood supply to the periodontal membrane.

The results, which were all tested statistically, showed that the blood supply to the periodontal membrane increases gradually from tooth to tooth towards the posterior sections of the dentition, and this increase is similar in both jaws. The blood supply of the individual periodontal membrane is greatest in the gingival and least in the middle third. There are no significant differences in the blood supply to the four surfaces of a socket.

The number of small perforations with a diameter of less than 150 μ is considerably greater than the number of large ones, and the latter are most frequently located in the gingival and apical thirds of the alveolus. The significance of these findings is discussed.
Function of epithelial rests as suggested by their ultrastructure
Authors: Valderhaug Jakob P. , Nylen Marie U.
Published: July 2006

Based on the evidence produced in this investigation it is apparent that what has been termed “Epithelial Rests of Malassez” are groups of epithelial cells surrounded by an outer argyrophilic limiting membrane. Further it is evident that the cells bear a strong resemblance to the epithelial cells seen in the basal layers of epidermis and the oral mucous membranes and have little or nothing in common With secretory cells. Based on the ultrastructural morphology and histochemical evidence, “resting epithelial cells” seem to be an appropriate description of these cell groups. Presumably, however, the cells contain all the necessary components to meet whatever functional demands may be placed upon them through environmental alterations.
Condylar adaptation to a change in intermaxillary relationship
Authors: FOLKE LARS E. A. , STALLARD RICHARD E.
Published: July 2006

Twenty Sprague‐Dawley rats were utilized to study the effects of a distal occlusion on the mandibular joint. The experimental period varied from one to four weeks. Cellular behavior and synthesis of new bone was revealed radioautographically after the injection of tritiated thymidine and tritiated proline respectively. The following structures within the joint were studied: (1) the fibrous layer of the articular fossa, (2) the fibrous and (3) the embryonic zone of the condyle. The number of labeled cells decreased in all areas analyzed after the first week of experiment but by two weeks had increased above the control. At four weeks, while still higher than the control, the radioactive index was decreasing. Of the structures studied, the embryonic layer showed the greatest response in number of cells undergoing DNA synthesis due to: (1) growth, (2) age, and (3) distal displacement of the mandible. Within the fibrous layer of the condyle and articular fossa, however, except for the central portion of the latter, the difference in radioactive index between control and experimental groups was negligible. Concomitant with the downward and forward growth of the mandible the number of cells undergoing DNA synthesis was highest in the posterior portion of the condyle. Initially, resorption was observed in the area of the external pterygoid attachment of the condyle followed by new bone formation as evidenced by tritiated proline. From this investigation the following conclusions were drawn: (1) The cells within the embryonic zone of the condylar cartilage can be stimulated, even in the adult, to increase their rate of cellular division to adapt to changes in mandibular position. (2) The articular fossa and disc remain unaltered following distal mandibular displacement. (3) Tension within the external pterygoid muscle will result in gross morphologic alterations on the anterior border of the condyle.
A study of periodontal vascularization 10 different laboratory animals
Authors: CARRANZA F. A. , ITOIZ M. E. , CABRINI R. L. , DOTTO C. A.
Published: June 2006

The blood vessels of the periodontium of the rat, mouse, hamster, guinea pig, cat and dog were studied with Wachstein and Meisel's technique for the demonstration of adenosine‐triphosphatase. In all species, a vascular plexus was found in the periodontal ligament, running in a general direction parallel to the long axis of the tooth and located closer to bone than to cementum. There was increased vascularity close to areas of active enamel formation (guinea pig molar and continuous growing incisors of all rodents). In the gingival tissues of all animals studied, an important annular plexus was found close to the epithelial cuff.
The influence of bacteria and irritation in the initiation of periodontal disease in germfree and conventional rats
Authors: Rovin Sheldon , Costich Emmett R. , Gordon Helmut A.
Published: July 2006

Within the conditions of the experimental design, this study has provided laboratory evidence that microorganisms were necessary for the occurrence of inflammatory periodontal disease. Furthermore, this investigation has shown that the presence of both local irritation and microorganisms was necessary to produce periodontal inflammation. However, neither factor alone was capable of producing the inflammation. The results of this study have shown that a type of dental calculus may be formed in the absence of microorganisms. However, the same results have demonstrated that the presence of microorganisms greatly facilitates the formation of calculus. The presence of polymorphonuclear leukocytes in the gingival crevices and tissues could not be explained on the basis of bacteria and/or irritation. It was postulated that these cells are a normal component of the gingival tissues of these animals and that their presence does not constitute a pathologic process. The findings of the present study were considered with those of other studies. From this comparison it was suggested that differences in animal species and strains should be considered when evaluations and extrapolations of experimental results are made.
The effect of sex hormones on inflammation
Authors: Lindhe J. , Sonesson B.
Published: July 2006

The present investigation was concerned with the effect of the progestogen hormone, DuphastonR, on the inflammatory reaction of rats. The granuloma pouch technique elaborated by Selye was used. The injection of 25 ml of air into the dorsum of the rat created a subcutaneous sac, into which the hormone and the irritant were deposited. Injections of 1 % solution of croton oil (the irritant) into this sac produced a pronounced inflammatory reaction in the connective tissue of the wall of the sac and formed a thick granulomatous membrane. If the progestogen was deposited into the granuloma pouch at the same time as the eroton oil or on the previous day, the membrane, compared with that induced solely by the croton oil was much thinner. Progestogen itself injected into the air sac produced no granulomatous membrane at all.

These results seem to indicate that the hormone progestogen may depress the inflammatory reaction of the connective tissue induced by the croton oil. In current experiments the effect of estradiol, gonadotropin and relaxin on the granuloma pouch inflammation is being studied.
An evaluation of the effects of collagen implants on new bone formation in vivo
Authors: Solomons C. C. , Gregory G. W.
Published: July 2006

Certain polypeptides have been shown to accelerate the formation of hydroxapatite crystals in virto. This investigation was designed to evaluate this phenomenon in vivo. Ox bone citrate‐soluble collagen, by itself and pepsin treated, was implanted into small artifically produced defects in the maxillae of 35 rats. An indication of subsequent new bone formation was obtained by measuring the uptake of tetracycline by the defects at definite intervals after implantation. By the end of 14 days, tetracycline uptake by defects filled with untreated collagen reached a maximum of 17 times that of unimplanted controls. By 10 days, pepsin treated collagen accelerated tetracycline uptake 18 times control values. The tetracycline content in both the experimental and control defects was essentially the same after 35 days. From this experiment it is concluded that citrate‐soluble collagen accelerated bone mineral deposition.
Correlation between articular eminentia and the depth of glenoid fossa
Authors: Quirch Jose S. , Carraro Juan J. , Itotz Maria E.
Published: July 2006

The possibility of a correlation between the inclination of the articular eminentia and the depth of the glenoid fossa of the temporomandibular joint was studied in 95 students (52 females and 43 males), with an average age of 22 years. A significant correlation was found when the whole material was analysed and when subjects with Angle's Class I occulsion were analysed separately. No significant correlation was found in subjects with an Angle's Class II occlusion. Class III occlusions were not studied.
Analysis of some elements in supra‐ and subgingival calculus
Authors: Lundberg M. , Söremark R. , Thilander H.
Published: June 2006

By means of thermal neutron activation and gamma ray spectrometry the concentrations of chloride, bromide, copper, manganese, sodium and strontium have been analyzed in supra‐ and subgingival calculus from the same teeth of adult humans. Although all the elements analyzed, except manganese, showed higher concentration levels in the subgingival than in the subgingival calculus, the difference was statistically significant only for sodium and strontium.
Oral collagen biosynthesis in the guinea pig
Authors: Claycomb C. K. , Summers G. W. , Dvorak E. M.
Published: July 2006

Collagen biosynthesis, as measured by conversion of 3‐4 3H‐proline to 3H‐hydroxyproline, was studied in guinea pig oral tissue and skin during normal growth, ascorbic acid depletion and following administration of ascorbic acid to scorbutic animals. Collagen breakdown in oral and skin tissue of normal animals was determined by measuring the depletion of 14C‐hydroxyproline over a seven month period of time. Oral collagen demonstrated a high level of metabolic activity, thus providing biochemical support to the histo‐pathological concept that periodontal tissues exist in a state of continuous wound healing and repair.
Some histological and histochemical observations on the connective tissue of chronically inflamed human gingiva
Authors: Melcher A.H.
Published: July 2006

This investigation was undertaken during the tenure of a Research Fellowship in the Institute of Dental Surgery, University of London, and a Leverhulme Research Fellowship in the Department of Dental Science, Royal College of Surgeons of England. Some of the findings were included in a Thesis submitted to the University of London for the Degree of Doctor of Philosophy.

One hundred and fifty biopsies of human gingiva, removed randomly from patients undergoing gingivectomy, were examined in the light microscope. Cold microtome and paraffin sections were prepared. Eosin, Mallory's PTAH, acid solochrome cyanine and chlorantine fast red, the Gomori aldehyde fuchsin, resorcin fuchsin and orcein methods for elastic fibres, and silver impregnation were used to colour collagen fibres; fibrin was stained by the DMAB method, and mucosubstances by the paS, DMPD, alcian blue and the aldehyde fuchsin methods. All the interdental gingival septa exhibited an ulcerated col. The intercellular substance of the connective tissue was not separated in cold microtome sections, as in paraffin sections, and probably more faithfully reflected the state of the tissue in vivo. However, cell detail in paraffin sections was clearer than in cold microtome sections. The collagen fibres in inflamed connective tissue were found to disintegrate and to lose their affinity for stains with which they usually react, but were not coloured by stains for elastic fibres during the process, nor by the DMAB method. The distribution of neutral and acid mucosubstances was found to overlap in healthy connective tissue. Neutral mucosubstances became less reactive in inflamed areas, but the reactivity of acidic mucopolysaccharides, which could also be demonstrated by two of the three stains used for elastic fibres, increased at the periphery of these areas, and was thought to be associated with fibrogenesis.
Acute infectious oral necrosis among young children in the Gambia, West‐Africa
Authors: Malberger E.
Published: July 2006

Among 7,650 patients who attended the oral surgery clinic in the Royal Victoria Hospital, Bathurst, Gambia, between February 1964 and March 1965, were 50 young children between the ages of 1 to 6 years who suffered from acute oral necrotizing diseases.These disease processes started with necrosis and ulceration of interdental papillae and often continued to the most severe stage of fulminating necrosis, frequently associated with death. The disease intensity was inversely related to the child's age.

A search for oral factors contributing to this condition was made in a survey of the entire child population of 4 Gambian villages. 361 children, 1 week to 5 1/2 years old were examined. Poor oral hygiene and gingivitis were found to be common in these children. Food debris in various amounts were found in 71 per cent of the children over 18 months of age. Periodontal diseases were already found in 9 per cent of the 18 month‐old children. In the 3 to 4 year age group, 61 per cent of the children suffered from periodontal diseases which often were of a chronic nature. Bacterial smears showed a high incidence of Vincent's organisms.

Systemic factors apparently predisposing to the acute oral necrosis were improper nutrition, debilitation and lowered resistance brought about by endemic infectious diseases.
Pain experience in periodontal surgery
Authors: Strahan J. D. , Glenwright H. D.
Published: July 2006

A trial is described during which the pain experienced by 200 patients who had undergone periodonta! surgery is examined. Pain was experienced by 73.5 % of patients and was severe in 21.0%. A greater proportion of patients who had undergone complicated surgery experienced pain than those who had undergone simple surgery. A prediction of the degree of pain forecast by the surgeon was correct in only 47.5 % of cases. Many patients were prepared to accept pain rather than to take analgesics when they had not been specifically recommended to do so. Women who had pain were much more likely than men to take analgesics. Analgesics of the patients’ own choice were effective. The use of analgesics following periodontal surgery is recommended.
Errors in the clinical assessment of periodontal destruction
Authors: Glavind Leif , Löe Harald
Published: June 2006

Pocket depth and loss of attachment were measured twice in millimeters on 1,335 surfaces of 335 teeth in 63 men aged 20‐40 years. The measurements were performed by one examiner. No systematic error in measuring pocket depth and loss of attachment was found. The method error for mean pocket depth was ± 0.10 mm and for mean loss of attachment ± 0.11 mm. The method error for single measurements was ± 0.36 mm and ± 0.41, respectively. This shows that the millimeter is an appropriate unit for measuring pocket depth and loss of attachment, and that both parameters may be assessed to approximately the same degree of accuracy.
Gingival exudation during the menstrual cycle
Authors: Lindhe Jan , Attström Rolf
Published: June 2006

This investigation was undertaken to study the variations in gingival fluid flow during the menstrual cycle in a group of young females. The material consisted of 17 female student nurses, 19‐23 years of age (mean 19,8 years) with eight male students, aged 20‐23 (mean 21,9 years) acting as controls. The mesial aspects of the buccal mesial gingiva of five maxillary incisors and canines were examined. Intra‐crevicular sampling of gingival fluid was performed in accordance with the technique described by Brill (1959) and Egelberg (1964). The day of ovulation was determined by cytologic examination of oral scrapings. The mean exudate values on the five menstrual days were 0.8, 0.8, 0.8, 0.8 and 0.9. The corresponding value on the day of ovulation was 1.2. The difference between the exudate values of the menstrual phase and the ovulatory day is statistically significant at the 0.1 per cent level. In the group of male students there was no significant difference between the fluid scores from various test days and periods of days. The data from the present investigation show that, in young females, there are variations in amount of gingival fluid, which can be correlated to the different phases of the menstrual cycle.
Vestibular sulcus extension surgery in cases with periodontal disease
Authors: Bergenholtz Axel , Hugoson Anders
Published: June 2006

Vestibular sulcus extension surgery was performed on 16 patients. The periodontal condition was assessed by measuring the depth of the periodontal pockets and from colour photographs just before and 12 months after the operation. An X‐ray cephalometric examination was carried out before, immediately after the operation and 1, 3, 6 and 12 months later. An analysis of the radiographs to determine the depth of the vestibule sulcus showed that during the first month there was a marked relapse, though with some residual gain, which steadily increased up to the 12‐month followup. The ultimate gain was on average 2‐3 mm (x = 2.1 mm). There was no difference between the pre‐ and postoperative mobility of the bestibular sulcus. There was no correlation between the increase in the depth of the vestibular sulcus and the periodontal condition. The symptoms and signs associated with the operation were minor.
Hertwig's sheath in the rat incisor
Authors: Shibata F. , Stern I. B.
Published: June 2006

A study was undertaken to reveal the histomorphologic nature of Hertwig's epithelial root sheath in the mandibular incisor of the young Sprague‐Dawley rat. Hertwig's epithelial sheath was found to be composed of three distinct cell layers: (1) inner dental epithelium, (2) stellate reticulum, and (3) outer dental epithelium. The inner dental epithelium and outer dental epithelium were simple cuboidal to low columnar cell layers whereas the stellate reticulum was a stratified squamous layer. As one proceeded incisally from the basal loop, the three cell layer diminished to two with the disappearance of the stellate reticulum. Further forward, the two cell layer became a single layer with the absence of the outer dental epithelium. The remaining inner dental epithelium eventually became discontinuous and was replaced by connective tissue elements. The inner dental epithelium and outer dental epithelium of the intact sheath were separated from the adjacent connective tissue by a distinct non‐metachromatic, PAS‐alcian blue positive basement membrane. The membrane next to the inner dental epithelium was followed incisally onto the external surface of the dentin. Epithelial rests were not identifiable in the periodontal ligament. In other words, an island of epithelial cells surrounded by a distinct basement membrane was not observed.
The effect of sex hormones on inflammation
Authors: Lindhe Jan , Sonesson Bertil
Published: July 2006

The present study was concerned with the effect of the hormones progestogen, oestrogen, and chorionic gonadotropin on the inflammatory reaction induced in the rat by 1 % croton oil. The granuloma pouch technique (Selye, 1952) was adopted as a standardized model of inflammatory reaction. A granuloma pouch developed within nine days following 2 injections of 1 ml 1 % croton oil solution. The thickness of the pouch wall was 710 μm.

If 1 ml of any of the sex hormones used was deposited into the air sac immediately before the injection of the croton oil, the reaction was less extensive. The wall of the granuloma pouch in these cases was about 300 μm thinner than that produced by 1 % croton oil alone, If the connective tissue was perfused with any of the hormones 5 hours or 24 hours prior to the croton oil injection, the pouch wall thickness was even less.

It is concluded that the sex hormones progestogen, oestrogen, and chorionic gonadotropin act as antiphtogistic substances on the acute inflammatory process induced by the croton oil.
Microscopic evaluation of the healing and revascularization of free gingival grafts
Authors: Oliver Richard C. , Löe Harald , Karring T.
Published: July 2006

The objective of this study was to observe the microscopic appearance of the healing and revascularization of free gingival grafts when placed over periosteum. Seven rhesus monkeys were used to provide observation periods of 0, 2, 4, 5, 7, 8, 11, 14, 17, 21, 28, and 42 days following surgery. After dissection and excision of a split flap in the anterior region to prepare the graft bed, a mucoperiosteal graft of attached gingiva from the buccal of the premolar area was sutured in place. The animals were injected with carbon serum just before sacrifice and after preparation the histologic and cleared specimens were studied under the microscope.

The results indicate that the healing and revascularization of free gingival graft and skin grafts are similar. Cellular nutrition was maintained for the first few days by a “plasmatic” circulation. Revascularization occured initially by anastomoses between vessels of the graft bed and pre‐existing vessels in the graft and later by capillary budding which penetrated the graft. Carbon serum was present in the vessels of the graft at four days. There was increasing vascular density up to seven days followed by a gradual reduction and return to a normal vascular pattern after 14 days. The graft was initially separated from the bed by a thin layer of fibrinous exudate. Fibroblasts proliferated into the area and a firm fibrous union to the periosteum was apparent between 7–11 days. Initial disintegration of most of the graft epithelium ccured. Re‐epithelialization resulted from migration of new epithelium from adjacent gingiva and from surviving basal cells of the graft epithelium. The epithelium had a relatively normal appearance by 14 days although new keratinization was not apparent for 28 days. The connective tissue disintegrated in portion of some of the graft and was replaced by granulation tissue which delayed healing.
Fasting and postprandial serum glucose in relation to periodontal status
Authors: Shannon Ira L. , Kilgore Willis G.
Published: July 2006

Fasting and 2‐hour postprandial serum glucose measurements were performed on 510 healthy young adult males. Subjects were divided into four periodontal index categories, and the data for each group for the three glucose variables were analyzed statistically. These variables were found not to be significantly related to periodontal status.
Mast cells of the human gingiva
Authors: Zachrisson Björn U.
Published: July 2006

Comparative histochemical studies with specific regard to the demonstration of mast cells were carried out on 21 different chronically inflamed marginal gingival specimens. For the demonstration of sulphated acid mucopolysaccharides two metachromatic stains were used‐toluidine blue (pH 1.0) and acridine orange (pH0.5)‐, as well as one orthochromatic stain‐ astra blue (pH 0.2–0.3). In addition the alcian blue‐safranin sequence was employed to distinguish between weakly and strongly sulphated mucopolysaccharides. Trypsin‐like esterase activity was demonstrated by the EACNAS‐GBC technique. The metachromatic stains used stain mature mast cells specifically, while the non‐metachromatic techniques stain immature mast cells as well. The chemical backgrounds for the different staining reactions are discussed. The chronically inflamed human gingivae were found to be rich in both mature and immature mast cells. The great majority of the immature mast cells were found within the pocket area of the connective tissue. Here, the number of mature mast cells was significantly smaller than in the oral area. The distribution of the different mast cell variants indicate a relation between mast cells and diffusible products from the gingival bacterial plaque.