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Biomedical subjects

S M Adair

Publications and source records attributed to S M Adair.

At least 19 recordsLinked to original sources
PubMed2000

Stentless aortic valve replacement with Freestyle or Toronto SPV: an early comparison.

BACKGROUND: Stentless aortic xenograft valves have been developed to overcome the disadvantages of conventional stented prostheses. We have implanted two new aortic bioprostheses: the Medtronic Freestyle and the St. Jude Toronto SPV. Early results are compared. METHODS: Forty-four Freestyle valves were implanted using a freestanding total root technique. Fourteen subcoronary Toronto SPV bioprostheses were implanted. Sixty-four percent of both groups (28 of 44 Freestyle and 9 of 14 Toronto SPV) underwent concurrent procedures. RESULTS: Ischemic time was 117 +/- 21 minutes for Freestyle and 124 +/- 19 minutes for Toronto SPV. There were no operative deaths or valve-related reoperations. Aortic valve area was 1.83 +/- 0.51 cm2 for Freestyle and 1.80 +/- 0.51 cm2 (p = 0.89) for Toronto SPV. Transvalvular gradient was 8.03 +/- 4.09 mm Hg for Freestyle and 12.4 +/- 1.82 mm Hg (p = 0.002) for the Toronto SPV. Aortic regurgitation was not experienced in any Freestyle patients, while Toronto SPV patients were graded as none to trace 79% (11 of 14), mild 14% (2 of 14), and moderate 7% (1 of 14). CONCLUSIONS: Aortic valve replacement with the Freestyle and Toronto SPV required equal time for implantation and had equal effective orifice areas. Freestyle had lower transvalvular gradient and less aortic insufficiency without increasing morbidity or mortality.

Aged↗
PubMed2000

Prevention of dental disease. The role of the pediatrician.

Evidence increasingly suggests that to be successful in preventing dental disease, we must begin preventive interventions within the first year of life. Pediatricians are well positioned to begin this process with early assessment of oral health and provision of anticipatory guidance, including ensuring that patients establish a dental home in addition to their medical home. This article provides information that will enable pediatricians to assess caries risk and provide practical and effective advice to parents about preventing dental disease, including oral hygiene, diet, and fluoride recommendations.

Cariostatic Agents↗
PubMed1999

Aortic root replacement with the freestyle stentless porcine aortic root bioprosthesis.

BACKGROUND: Stentless porcine prosthetic valves offer several advantages over traditional valves. Among these are superior hemodynamics, laminar flow patterns, lack of need for anticoagulation and perhaps improved durability. METHODS: One hundred and twelve patients were operated on from September 17, 1992 to April 13, 1998 as part of a multi-center worldwide investigation. All patients received a total aortic root replacement. Patients were evaluated postoperatively at discharge, 3 to 6 months, and yearly by clinical exam and color flow Doppler echocardiography. RESULTS: There were 4 deaths either in the hospital or within 30 days after surgery for an operative mortality of 3.6%. No patients experienced structural valve deterioration, non-structural valve deterioration, paravalvular leak, unacceptable hemodynamic performance, or postoperative endocarditis. The linearized rates for survival and thromboembolic complications at 5 years were 82.8% and 90.5% respectively. Excellent hemodynamic function is demonstrated by very low gradients, large EOA, and an exceedingly low incidence of any aortic regurgitation. CONCLUSIONS: The Medtronic Freestyle aortic root bioprosthesis can be used safely to replace the aortic root for aortic valve and aortic root pathology. Root replacement allows optimal hemodynamic performance with no significant aortic regurgitation. Early and intermediate results are encouraging, but further follow-up is needed to determine valve durability.

Adult↗
PubMed1999

Fluoride in whole saliva, parotid ductal saliva and plasma in children.

The purpose was to investigate the relation between fluoride concentrations in whole saliva, parotid ductal saliva, and plasma in 5- to 10-year-old children (n = 17). Two stimulated whole-saliva samples were obtained from each child. Before the second sample was obtained, each child rinsed several times with a total of 100 ml of deionized water. Parotid saliva samples were obtained by use of a Lashley cup. Fluoride concentrations were determined by fluoride ion-specific electrode after diffusion with hexamethyldisiloxane. Rinsing with deionized water did not significantly reduce the fluoride concentration in whole saliva. The whole-saliva fluoride concentrations were not significantly related to those in plasma or parotid ductal saliva. Parotid fluoride concentrations, however, were significantly related to plasma fluoride concentrations (p < 0.0001) by a proportionality constant of 0.80. It was concluded that parotid salivary fluoride concentrations can be used to estimate plasma fluoride concentrations in 5- to 10-year-old children.

Child↗
PubMed1999

Overview of the history and current status of fluoride supplementation schedules.

Clinical trials of dietary fluoride supplements began in the 1940s in an effort to bring the benefits of fluoride to those who did not receive it through their drinking water. Following the early success of these trials, the Council on Dental Therapeutics of the American Dental Association (ADA) published its first recommendations for fluoride supplementation in 1958. The American Academy of Pediatrics (AAP) followed with its own recommendations in 1972. During the 1970s a variety of alternative schedules appeared in the literature, most in reaction to the findings of unexpectedly high levels of enamel fluorosis in children being supplemented with the AAP schedule. In 1979 the ADA and AAP agreed on essentially identical schedules. During the 1980s, however, the prevalence of enamel fluorosis continued to increase, and fluoride supplements were found in some studies to be a risk factor for fluorosis. This finding prompted another round of dosage schedule recommendations in the early 1990s. This paper presents a history of fluoride dosage recommendations and reviews the recent proposals for reducing supplement dosage.

Adolescent↗
PubMed1999

Comparison of results using "freestyle" stentless porcine aortic root bioprosthesis with cryopreserved aortic allograft.

Aortic valve replacement with natural heart valves offer the advantages of superior hemodynamics, laminar flow patterns, lack of need for anticoagulation, and perhaps improved durability. This study compares 5-year results for two stentless aortic valves. In 1992, two prospective clinical trials using two different stentless aortic valves were initiated at our center. The Freestyle stentless porcine aortic root bioprosthesis (SPB) was placed in 106 patients, and cryopreserved aortic allografts (CAA) were placed in 174 patients using a freestanding total root replacement technique in each series. The mean systolic gradient for the SPB was 7.5+/-4.4 mm Hg at discharge and 5.9+/-3.1 mm Hg at 5 years. The mean systolic gradient for the CAA was 6.4+/-3.3 mm Hg at discharge and 5.0+/-2.2 mm Hg at 5 years. At discharge 92.2% of SPB patients had no aortic insufficiency (AI) and 7.8% had trivial AI. In all, 92.9% of CAA patients had no AI at discharge, and 7.1% had mild AI. At 5-year follow-up, 100% of the SPB had no AI, and only 20% of the allograft patients had no AI. The remainder, 80%, had mild AI. Excellent hemodynamic function was seen with both SPB and CAA. A lower incidence of nonhemodynamically significant AI was observed in the SPB group. Preoperative factors such as chronic renal failure and endocarditis may have adversely affected durability in the allograft group, but long-term follow-up is still required to determine durability.

Adult↗
PubMed1998

Ultraconservative and cariostatic sealed restorations: results at year 10.

Changes in restorative techniques and the development of newer restorative materials have allowed for the use of more conservative cavity preparations. This 10-year study evaluated bonded and sealed composite restorations placed directly over frank cavitated lesions extending into dentin vs. sealed conservative amalgam restorations and conventional unsealed amalgam restorations. The results indicate that both types of sealed restorations exhibited superior clinical performance and longevity compared with unsealed amalgam restorations. Also, the bonded and sealed composite restorations placed over the frank cavitated lesions arrested the clinical progress of these lesions for 10 years.

Adolescent↗
PubMed1997

Randomized clinical trial of the effect of prenatal fluoride supplements in preventing dental caries.

This randomized, double-blind study tested the caries-preventive efficacy of prenatal fluoride supplementation in 798 children followed until age 5. Initially, 1,400 women in the first trimester of pregnancy residing in communities served by fluoride-deficient drinking water were randomly assigned to one of two groups. During the last 6 months of pregnancy the treatment group received 1 mg fluoride daily in the form of a tablet and the control group received a placebo. Both treatment and control subjects were encouraged to use postnatal dietary fluoride supplements. Caries was measured in children at age 3 and 5 while fluorosis was assessed at age 5. Caries activity was very low in both study groups: 92% of children remained caries-free in the treatment group and 91% remained caries-free in the placebo group. Fluorosis was observed in 26 subjects, all classified as very mild. Overall, there were no statistically significant differences in the study groups with respect to caries and fluorosis in deciduous teeth. The study had sufficient power to detect an absolute risk reduction of 5.1% while only a 1.5% reduction was observed. These findings do not support the hypothesis that prenatal fluoride has a strong caries-preventive effect.

Cariostatic Agents↗
PubMed1994

Effect of artificial saliva and calcium on fluoride output of controlled-release devices.

The purpose of this in vitro study was to assess the effect of graded concentrations of calcium in artificial saliva on the output of fluoride from HEMA/MMA controlled-release devices. After the initial release rates were determined in deionized water, the devices were assigned to five groups. The devices of one group remained in deionized water throughout the 19-day study while those of the other groups were placed in artificial saliva containing 0, 4.5, 8.0, or 12.0 mg% calcium on days 4-13. Ten devices of each group were placed in deionized water again on days 14-17 and then in 0.1 mol/l HCl on days 18-19. The five devices of each group that were not placed in deoinized water on day 14 were inspected for surface crystals and then placed in 1 mol/l KOH for 2 days. The fluoride release rates in artificial saliva were reduced by 71-90% and in proportion to the calcium concentration. The release rates in deionized water (days 14-17) approached the baseline values; they exceeded baseline rates by 13-49% while in HCl. The fluoride release rates did not differ among the groups while in KOH, but calcium output was directly related to the calcium concentration of the artificial saliva. The results indicate that fluoride release from HEMA/MMA devices is markedly reduced in artificial saliva and that the reduction is proportional to the concentration of calcium.

Calcium↗
PubMed1994

Interexaminer agreement for readings of dip slide tests for salivary mutans streptococci and lactobacilli.

This study reports the interexaminer agreement of three pairs of evaluators of salivary dip slide tests for mutans streptococci and lactobacilli. 717 Cariescreen SM and Bactotest LB dip slides were available for assessment by 2 dentists and 1 dental hygienist. A single calibration session was held prior to the onset of the study. Each dip slide was read once by each examiner independently. Among the three pairs of examiners, Pearson R values ranged from 0.84 to 0.90 for Cariescreen and from 0.78 to 0.87 for Bactotest. Kappa statistic values ranged from 0.56 to 0.61 for Cariescreen and from 0.70 to 0.74 for Bactotest. The range of agreement was from 72.2 to 76.9% for Cariescreen and from 86.4 to 88.3% for Bactotest. The majority of disagreements were of one category in magnitude, though there were a few disagreements of greater magnitude. This study found moderately strong agreement among the three examiners; it suggests that multiple examiners of dip slide tests carefully calibrated initially and periodically to ensure a high level of agreement.

Child↗
PubMed1994

Pit and fissure sealant application using a drying agent.

This clinical investigation assessed the retention of pit and fissure sealants with and without the use of a post-etching drying agent in pediatric dental patients. Twenty eight healthy patients with four fully erupted, non-carious first permanent molars participated. Sixteen males and 12 females, 5-12 years of age, each received four sealants, two with and two without a drying agent. Sealants were placed by three dental operators. Assignment for sealant application (with and without drying agent) was based on a computer-generated randomization table. Sealant application involved cleansing of the teeth with a non-fluoridated prophylaxis paste followed by rinsing 60 seconds with air/water spray, enamel conditioning with 40% phosphoric acid for 60 seconds, rinsing with air/water spray for 60 seconds, application of drying agent for 5 seconds, application of sealant material, and light curing for 60 seconds. Modified USPHS (Ryge) criteria were used to evaluate interfacial staining, secondary caries, marginal integrity, and surface texture. Sealant retention was evaluated as fully retained or lost (failed). All 28 participants returned for the 12-month recall visit. Four evaluators reported a 91% overall retention rate. Of the 56 teeth sealed without a drying agent, there was a 13% (n = 7) failure rate compared to 5% (n = 3) failure rate for the 56 teeth sealed with a drying agent. These results were not statistically significant (P > 0.05) based on the log-rank test.

Child↗
PubMed1993

Caries risk assessment by a cross-sectional discrimination model.

Although the prevalence of dental caries is continuing to decline, it still affects a majority of the US population and can be a serious problem for those afflicted. The objective of this project was to develop and perfect a model for assessment of risk of dental caries onset in children. In the first study, reported herein, a set of clinical, microbiological, biochemical, and socio-demographic variables was identified that distinguished, with an acceptable level of sensitivity and specificity, between children who had no previous caries experience and children who had high caries levels. A total of 313 children--age 12-15 years, 140 from a fluoridated community and 173 from a fluoride-deficient community--was selected on the basis of previous caries experience, either zero DMFS or high DMFS (> or = 6 in the fluoridated or > or = 8 in the fluoride-deficient community). Clinical exams for DMFS, dental fluorosis, and plaque were conducted. Stimulated whole saliva was collected for analysis of mutans streptococci, lactobacilli, total viable flora, and fluoride concentration. A questionnaire was used for collection of demographic data as well as information on prior fluoride exposure, dietary habits, and oral hygiene practices. By means of discriminant analyses, with use of seven key clinical and laboratory variables, it was possible for zero-DMFS subjects to e classified correctly (specificity) in 77.6% of cases in the fluoridated community and in 86.1% of cases in the fluoride-deficient community. High-caries subjects were classified as such (sensitivity) in 79.3% and 88.1% of cases, respectively.

Adolescent↗
PubMed1993

Caries risk assessment in a longitudinal discrimination study.

Our objective was to develop and perfect a model for the assessment of risk of dental caries onset in children. Even though dental caries prevalence in children is continuing to decline, there is still a significant minority for whom it is a problem. In this study, we sought to ascertain whether a set of variables selected in a previous cross-sectional study could be used to differentiate between caries-free six-year-olds who would or would not subsequently present with clinically-detectable caries. A total of 472 caries-free six-year-olds--286 from a fluoridated community and 186 from a fluoride-deficient community--was selected. Clinical examinations for DMFS, dental fluorosis, and plaque were conducted. Stimulated whole saliva was collected for analysis of mutants streptococci, lactobacilli, total viable flora, and fluoride, calcium, and phosphate concentrations. A questionnaire was used for collection of demographic data as well as information on prior fluoride exposure, dietary habits, and oral hygiene practices. By means of linear discriminant analyses, it was possible to predict correctly which children would develop caries within six to 12 months (sensitivity) in 82.8% of cases and which children would not develop caries during that period (specificity) in 82.4% of cases.

Apatites↗
PubMed1991

Associations of microbiological factors and plaque index with caries prevalence and water fluoridation status.

Plaque indices, numbers of mutans streptococci, lactobacilli and total viable flora in plaque and saliva were assessed as part of a large-scale cross-sectional study designed to determine the factors that are associated with high caries activity in children. Subjects, 12 to 15 years old, residing in areas where the water supplies were either fluoridated (n = 140) or fluoride-deficient (n = 173) were studied. Mutans streptococci and lactobacilli numbers in saliva were positively correlated with plaque index. Plaque indices were significantly higher in the high-caries group than in the zero-caries group of the fluoride-deficient community. In the fluoridated community, there was no difference in the plaque index between the zero- or high-caries groups. In each community, pooled dental plaque and saliva harbored fewer mutans streptococci and lactobacilli in the zero-caries than the high-caries group. Greater numbers of mutans streptococci were found in the dental plaque and saliva of the zero-caries subjects in the fluoridated community than in the fluoride-deficient community, suggesting that a greater caries challenge can coexist with zero-caries status in the fluoridated community.

Adolescent↗
PubMed1991

Resolution of early lesions of juvenile periodontitis with tetracycline therapy alone: long-term observations of 4 cases.

Our previous studies have demonstrated that early-identified lesions of localized juvenile periodontitis (LJP) can be treated by the use of systemically administered tetracycline alone (1 gm/day for 6 weeks). This therapy results in arrest of disease progression, decreased pocket depths, gains in clinical attachment, and significant repair of alveolar defects. This paper reports on the long-term clinical and radiographic improvement in 4 subjects followed for 1 to 4 years after the completion of tetracycline therapy. Four patients (mean age 14 years) were examined 1 to 4 years following the completion of a single 6 week course of tetracycline. Mean pocket depth was reduced from the initial level of 7.1 mm to 3.6 mm. Mean attachment loss was reduced from 3.8 mm to 0.9 mm and angular bone defects had filled by an average of 72%. Pocket depths and attachment loss continued to decrease during the entire study period, while alveolar bone repair continued to increase. The findings support those of our previous investigation and confirm that: 1) early identified lesions of LJP can be effectively treated with 6 weeks of tetracycline therapy alone; 2) decreases in pocket depth, gains in clinical attachment, and repair of alveolar defects remain stable up to 4 years following antibiotic therapy; 3) clinical and radiographic improvement continues over time and may lead to complete resolution of some lesions; and 4) the reparative/regenerative potential of the periodontium in early onset disease in young individuals may exceed that observed in chronic adult periodontitis.

Adolescent↗
PubMed1991

Current fluoride therapy in dentistry for children.

The literature on fluoride therapy for children continues to document the effectiveness of systemic and topical delivery in reducing dental caries in the recipients. The value of optimally fluoridated water supplies continues to be confirmed, but studies reflect a growing concern for an increased prevalence of very mild and mild enamel fluorosis in both optimally fluoridated and fluoride-deficient communities. Studies document the need to educate health care professionals about appropriately prescribing supplemental fluorides. There is evidence of further need to minimize unnecessary ingestion of self-applied fluoride products, particularly dentifrices.

Child↗
PubMed1991

Practical clinical applications of sports dentistry in private practice.

Preparing a practice to become "trauma-ready" involves more than educating the dentist and the staff in the proper management of dentofacial trauma. All members of the office should understand their roles in preventing and treating trauma. They must be willing to provide care after hours when called upon to do so. Dentists who want to be more involved might wish to volunteer their services as sports dentists for local school or recreational league teams. The dentist who is conscious of his or her patients who are at risk for sports-related trauma will also find others in the practice who might benefit from many of the same protective devices that are being constructed for athletes. These include children involved in higher-risk activities, developmentally disabled patients, patients undergoing general anesthesia, and others. Being trauma-ready may open up several rewarding activities for the practice because of the many spin-off applications. The trauma-ready practice must also be cognizant of the some-times perplexing legal and insurance issues with regard to preventing and treating sport-related injuries. In addition to lowering the risk exposure to the practice, the dentist can help ensure the maximum third-party benefits for the patient.

Humans↗