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PubMed1995

Size-reduced cryopreserved pulmonary valve allograft for an RV-PA conduit: technical modification and functional evaluation.

Cryopreserved pulmonary allografts harvested from adults at the time of kidney donation were size reduced and used in two children with pulmonary atresia and ventricular septal defect. A technical modification for the creation of size-reduced pulmonary allograft conduits is described. Postoperative ultrasonic and cineangiographic assessments revealed excellent function of the pulmonary bicuspid valved conduit with a minimal pressure gradient and essentially no regurgitation. Although the long-term fate of cryopreserved bicuspid pulmonary valve and conduit is unknown, this conduit provides excellent handling characteristics that render allograft conduits preferable to synthetic conduits. In addition, the remodeled bicuspid pulmonary allograft conduits have exhibited excellent hemodynamic characteristics and are a reasonable alternative to other types of conduits when an appropriate size allograft is not available.

Adult↗
PubMed1990

Cementum thickness and mesial drift.

Cementum thickness increases uniformly with age, and questionably from functional stimulation due to tensional forces. Mesial drift of teeth results in tensional forces on distal root surfaces. This study evaluated whether there was any discernible effect on cementum thickness related to mesial drift in humans. The material consisted of maxillary and mandibular bicuspids and molars with their surrounding periodontia from 5 humans (mean age at death, 48.6 years). The teeth and tissues had been sectioned histologically in a mesio-distal plane, and the analysis for each tooth was done using 3 step-serial sections from the mid-buccolingual region. On the mesial and distal surface of each tooth, cementum thickness was measured in microns at 3 defined locations at a level representing the mid-point of root length for bicuspids and molars. Means from the measurements on mesial and distal surfaces were compared using descriptive and and inferential statistical methods. For each individual tooth analyzed, the cementum was thicker on the distal surface (range greater, 32-107%; mean, 69%). The statistical comparisons showed that cementum thickness on the distal surface was significantly greater for bicuspids (mesial, 135 microns: distal, 216 microns), molars (mesial, 154 microns: distal, 284 microns), and all teeth combined (mesial, 154 microns: distal, 284 microns). The magnitude of this difference became greater with increasing age. It was concluded that cementum thickness was markedly greater on the distal surfaces of teeth from adult humans, and that this may be due to functional stimulation from mesial drift over time.

Adult↗
PubMed2007

Aortic stenosis severity is not a risk factor for poststenotic dilatation of the ascending aorta.

BACKGROUND: Dilatation of the ascending aorta in aortic stenosis may be partly explained by intrinsic wall structure changes, but the relative contribution of altered hemodynamics is unclear. The aim of this study was to assess the association between ascending aortic dimensions and valve stenosis severity. METHODS AND RESULTS: An analysis of echocardiographic examinations was conducted in 296 patients with aortic stenosis (179 males, mean age 71 years), 57 with bicuspid and 239 with tricuspid aortic valve, mean transaortic gradient 43+/-20 mmHg, and not more than moderate aortic regurgitation. Aortic dimensions at the level of annulus, sinuses of Valsalva, sinotubular junction and proximal ascending aorta were measured. Only height (p<0.001), degree of aortic regurgitation (p<0.01) and presence of bicuspid aortic valve (p<0.001) were independent predictors of ascending aortic dimensions. CONCLUSIONS: An independent association between aortic pressure gradients and proximal ascending aortic dimensions was not observed in patients with bicuspid or tricuspid aortic valve stenosis. Therefore, the poststenotic dilatation of the ascending aorta is not explained by aortic stenosis severity itself. Possible nonhemodynamic causes deserve detailed study at the time of diagnosis.

Aged↗
PubMed2000

Pulmonary ventricular outflow reconstruction with a size-reduced cryopreserved pulmonary valve allograft: mid-term follow-up.

Surgical reduction of pulmonary allografts is being performed because of the shortage of allografts of suitable size for pediatric use. However, the outcome of size-reduced pulmonary allografts for pulmonary conduits is unknown. In the present study, cryopreserved pulmonary allografts harvested from adults at the time of kidney donation were size-reduced and used in 4 children, 2 with pulmonary atresia and ventricular septal defect and 2 with atrioventricular discordance, pulmonary atresia and ventricular septal defect. They all had undergone right and/or left modified Blalock-Taussig shunt operations with a 5-mm synthetic graft prior to the reparative operations. They underwent definitive repair with a size-reduced cryopreserved pulmonary allograft valved conduit and were followed up for 2-5 years. Postoperative echocardiographic and cineangiographic assessments revealed excellent function of the pulmonary bicuspidalized valves with a minimal pressure gradient and no, or only trivial, regurgitation. Although the long-term result of a cryopreserved bicuspid pulmonary valved conduit remains unknown, the remodeled bicuspid pulmonary allograft conduits showed excellent hemodynamic characteristics in mid-term follow-up and appear to be a reasonable alternative to other types of conduits when an appropriate-sized allograft is not available.

Adult↗
PubMed1998

Cardiovascular malformations and complications in Turner syndrome.

BACKGROUND: Turner syndrome (gonadal dysgenesis with sex chromosome abnormalities) is recognized to be a disorder in which cardiovascular malformations are common. The prevalence and natural history of these findings, the risk for aortic dissection, and the occurrence of cardiovascular disease have all been the subject of debate, as have been the American Academy of Pediatrics recommendations for cardiac screening of patients with Turner syndrome. OBJECTIVE: To evaluate a large population of patients both cross-sectionally and longitudinally to determine the prevalence of cardiovascular malformations, the risk for dissection of the aorta, to determine whether there are phenotype:karyotype correlations that can allow for specific recommendations, and to devise an appropriate screening protocol. DESIGN AND METHODS: Data have been collected for patients with Turner syndrome. These individuals have been seen in an ongoing clinic established for the study of the natural history of Turner syndrome. Data from physical examinations, evaluations by cardiologists, echocardiography results, medical and surgical complications, medical records, and causes of death were analyzed. A total of 244 of 462 individuals in this population with karyotype-proven Turner syndrome could be evaluated because echocardiograms had been obtained. In addition, the medical literature was reviewed for occurrences of aortic dissection in patients with Turner syndrome. RESULTS: A total of 136 (56%) of 244 of these patients had cardiovascular abnormalities, 96 (71%) were structural, 40 (29%) were functional, including hypertension (HBP), mitral valve prolapse and conduction defects. Coarctation of the aorta and bicuspid aortic valve, alone or in combination, comprised >50% of the cardiac malformations. Bicuspid valve was often not detected by examination, but only by echocardiography. Aortic dissection occurred in three of the patients. In one, it was traumatic; in a second, it occurred at the site of coarctation repair. The third patient had long-standing HBP with malignant obesity. In the literature, there have been 42 case reports of aortic dissection in Turner syndrome. In all except 5, predisposing risk factors of coarctation, bicuspid aortic valve, and/or HBP were present. Of these 5, sufficient information regarding predisposing risk factors was provided for only 2. No phenotype:karyotype correlations could be drawn with any certainty. CONCLUSIONS: When the diagnosis of Turner syndrome is made, a screening echocardiogram should be obtained. Referral to a cardiologist first may be appropriate, but physical examination does not substitute for visualization. Individuals with and without evidence of structural cardiac malformations should be monitored for HBP on a lifelong basis. In the absence of structural cardiac malformations or HBP, the risk for aortic dissection appears small, and repeated echocardiography or magnetic resonance imaging to follow aortic root diameters does not appear to be warranted based on data currently available. Protocols for following patients with structural malformations need to be individualized, and wholesale recommendations have little merit. A longitudinal study using magnetic resonance imaging or cardiac echocardiography to establish normal parameters for aortic root diameters and to follow aortic root changes is needed.

Adolescent↗
PubMed1990

New attachment formation following periodontal surgery in a dog.

We evaluated new attachment following treatment of experimental periodontitis in a canine model. Periodontal destruction was induced over an 8-month period using silk ligatures and a soft diet, and this remained stable for 170 days before surgery. After surgical scaling and root planing of eight bicuspid teeth, the apical end of the pockets was estimated using an occlusal stent and a periodontal probe, then marked with a blade. The root surfaces of three bicuspids were treated with citric acid for 3 min, and tetracycline salt was applied to the root surfaces of two teeth. The remaining three bicuspids served as controls. Postoperatively, no attempts were made to improve oral hygiene, and on day 48 light microscopic examination of biopsy materials revealed new attachment in all treated teeth. However, in some sections new cementum and new collagen formation was much more extensive and complete in both groups of experimental teeth than in the control teeth.

Animals↗
PubMed1999

Risk factors for coronary complications after stentless aortic root replacement.

Coronary complications after aortic root replacement (ARR) with pulmonary autografts have been reported to be more common than with other stentless biological conduits (homografts, xenografts). To verify this hypothesis, results with 84 consecutive patients having stentless ARR between January 1992 and January 1999 were reviewed. Fifty patients had autograft (Group 1) and 34 either homograft or xenograft (Group 2) ARR. Comparison of age (27+/-9 vs. 38+/-22 years, P = ns), prevalence of male sex (86% vs. 79%, P = ns), aortic root disease (30% vs. 44%, P = ns), congenital coronary anomalies (10% vs. 3%, P = ns), prior aortic procedure (16% vs. 15%), and need for associated procedures (26% vs. 24%, P = ns), did not disclose significant differences. Bicuspid aortic valve was more prevalent in Group 1 (56% vs. 9%, P = .001). Mean aortic crossclamp (154+/-28 vs. 120+/-24 minutes, P = .05) and bypass (216+/-30 vs. 192+/-58 minutes, P = .05) times were longer in Group 1. Early mortality was comparable (2% vs. 3%, P = ns) and caused by right ventricular ischemia in both groups. Overall prevalence of coronary complications was higher in Group 1 (10% vs. 3%, P = .04), all resulting in right heart ischemia. Intraoperative partial takedown of repair in 5 Group 1 patients, associated with CABG in 1, resulted in prompt resolution of myocardial ischemia in 4 (80%) and prolonged in 1, which ultimately died as a result of sepsis. Recovery was prompt in all 4 patients (mean ICU stay 35+/-28 hours) with no metabolic or echocardiographic evidence of myocardial infarction. At discharge echocardiography, satisfactory biventricular kinetics was found in all patients. Analysis of preoperative variables showed bicuspid aortic valve (83% vs. 33%, P = .01) and coronary anomalies (67% vs. 3%, P = .001) to be more prevalent in patients suffering from coronary complications. Stentless ARR is a safe procedure with low operative mortality, regardless of the type of biological conduit. Autograft ARR may be at greater risk of right ventricular ischemia in patients with bicuspid aortic valve and coronary anomalies. An aggressive intraoperative approach including partial takedown of repair may limit the morbidity of coronary complications.

Adolescent↗
PubMed2003

[Circulating test and analysis of clasp retention].

OBJECTIVE: To show the trend of the retention change during the circulation of the clasp dislodging and inserting, and to discuss the proper depth of the undercut for a specific clasp. It is also a basic study for the best designing of RPD. METHODS: The Chatillon force measuring instrument was used to record the variation of the retention of Co-Cr alloy casting Akers clasp when they were dislodging from undercuts of different depths (0.25 mm, 0.50 mm, 0.75 mm) on bicuspid and molar. RESULTS: The data was analysed of Correlation and Regression by SPSS 10.0 statistic software. The variations of the retention in the circulation are obvious from the different teeth and different undercut depths. It shows an attenuation trend in circulation (P < 0.01). After 400 times dislodging, in bicuspid group, the retention of the clasp used in 0.50 mm undercut became less than the one used in 0.25 mm undercut. While the retention of the clasp used in 0.75 mm decreases most obviously, it values 0.7670 kg. In molar group, the attenuations of the retention at different depths of undercut are similar, the retentions of the clasp still rank as, from great to less, 0.75 mm, 0.50 mm and 0.25 mm, in the depth of undercut. CONCLUSION: the proper depth of the undercut for bicuspid is 0.25 mm, and 0.50 mm for molar.

Dental Clasps↗
PubMed2004

Pathology and etiology of 110 consecutively removed aortic valves.

OBJECTIVES: To study the pathology and determine the etiology and prevalence of aortic valve disease from surgically removed aortic valve specimens. MATERIAL AND METHOD: All the native surgically excised aortic valves (AV) received from June 1997 to March 1999 (22 months) were studied macroscopically including cuspal measurements and microscopically. By preoperative echocardiographic and macroscopic studies, they were classified into functional disorders of predominant aortic stenosis (AS), aortic stenosis with regurgitation (AS-AR) and predominant aortic regurgitation (AR). The patients' medical records were reviewed and the clinical information was extracted. The etiology was determined according to the macroscopic, microscopic and clinical findings. RESULTS: Among 110 AV (76 isolated AV and 34 with concomitant mitral valves from patients aged 15-96 years, mean age 47.54 years; male:female = 1.39:1) there were 25 AS (22.73%), 34 AS-AR (30.91%) and 51 AR (46.36%) cases. Eighty-four (76.36%) were tricuspid, 16 (14.54%) were bicuspid and 10 were undetermined. Cuspal measurements of each disease were provided and compared. All AS specimens were related to moderate to severe calcification and causes included postinflammatory disease (14 cases, 56%; age range 38-67 years, mean age 53.29 years, male:female = 0.56:1), degenerative calcific change (11 cases, 44%, age range 56-76 years, male:female = 1.2:1; mean age 69 years of 5 tricuspid AV and 60.83 years of 6 bicuspid AV). In AS-AR, 29 cases (85.29%; mean age 47.10 years; male:female = 1.23:1) were attributable to postinflammatory disease and 5 cases (mean age 70.20 years; male:female = 1.5:1) to degenerative calcific change. In pure AR, there were 21 cases (age range 15-65 years, mean age 29.76 years) of postinflammatory disease, 14 cases of infective endocarditis (IE) and postIE (age range 20-63 years, mean age 42.21 years; all 10 IE cases contained gram positive cocci), 1 case (age 55 years) of bicuspid calcific change, 8 cases of AV with dilated valve ring, 5 cases of miscellaneous causes and 2 cases of indeterminate etiology. Aschoff bodies were found in 3 AR cases. Four of 18 postinflammatory AS-AR and 4 of 14 postinflammatory disease AR cases had past history of rheumatic fever. One postinflammatory AS also had infective endocarditis from gram positive cocci without clinical sign. Severe degenerative calcific change had a higher incidence of underlying diabetes (3 of 15 cases, 20%), hypertension (8 of 14 cases, 57.14%) and dyslipoproteinemia (9 of 13 cases, 69.23%) in comparison with 3.37% (3/89) for diabetes, 9.09% (8/88) for hypertension and 30.99% (22/71) for dyslipoproteinemia in other AV diseases in combination. CONCLUSION: The three common causes of severe AV functional disorders were postinflammatory disease (58.18%), degenerative calcific change (15.45%) and IE-postIE (12.72%). Underlying diseases of severe degenerative calcific change included hypertension, dyslipoproteinemia and diabetes. Macroscopic and microscopic examinations together with clinical information, echocardiographic findings and operative details are important in evaluating the etiology of valvular diseases especially in severely calcified specimens.

Adolescent↗
PubMedDate not supplied

Morphological evaluation of the surgically removed aortic and mitral valves.

In 2001, of the 114 valves surgically excised at the Iaşi Center of Cardiology from 59 men and 54 women (mean age 51 years; age range: 25 to 78 years), half were aortic and the other half mitral valves. The 57 aortic valves, from 20 women and 37 men (mean age 51.1; age range 25 to 78 years), had been surgically replaced. Functionally, 57.63 percent (30) were stenotic, 21.05 percent (12) were incompetent, and 26.31 percent (15) were both stenotic and incompetent (aortic disease). Pure stenosis was related to calcification of degenerative (73.3 percent), bicuspid (3.33 percent), post-inflammatory (20 percent), and undetermined (3.33 percent) causes. Pure regurgitation was not related to calcification and causes included infective endocarditis (50 percent), bicuspid valve (16.66 percent), postinflammatory (16.66 percent), aortic root dilatation (8.33 percent), and undetermined (8.33 percent). Aortic disease was secondary to postinflammatory etiologies (40 percent), degenerative calcification (33.33 percent), bicuspid and undetermined (13.33 percent each) causes. The reminder of 57 mitral valves, from 35 women and 24 men (mean age 45.5 years; age range 28 to 71 years), were surgically replaced. Functionally, 40.35 percent (23) were purely stenotic, 19.29 percent (11) were purely regurgitant, and 40.35 percent (23) both stenotic and regurgitant (mitral disease). The causes of pure stenosis were postinflammatory (presumably rheumatic) disease in 91.3 percent (21 cases) and degenerative disease in 8.7 percent (3 cases). Pure regurgitation etiology involved floppy valves in 45.45 percent (5 cases), degenerative disease in 27.27 percent (3 cases), postinflammatory disease in 18.18 percent (2 cases) and infective endocarditis 9.1 percent (1 case).

Adult↗
PubMed1991

[Congenital cardiopathies at an internal medicine service].

STUDY OBJECTIVE: Description of 32 cases of congenital heart disease in the adulthood, admitted in the First Department of Medicine of Hospital Santa Maria, Lisboa between 1980 and 1989. DESIGN: Retrospective study. SETTING: Admission from the Emergency Room and Outpatients Clinic to an Internal Medicine Department of a General Hospital. PATIENTS: Adult patients with congenital heart disease. MATERIAL AND METHODS: All the 32 cases of congenital heart disease admitted between the 1st January 1980 and the 31st December 1989 were studied retrospectively. The clinical findings diagnosis and special examinations were analysed. MAIN RESULTS: The admission age varied between 15 and 83 years old being 21 female (65.6%) and 11 males (34.4%). The 32 cases of congenital heart disease, were distributed as follows: 19 were atrial septal defects (ASD); 4 were bicuspid aortic valves; 3 were coarctations of the aorta; 3 were tetralogy of Fallot; 2 were patent ductus arteriosus; 1 was an Ebstein anomaly with cianosis. From the 19 cases of atrial septal defect (ASD), 15 were female and 4 were male. The mean age of admission was 57.1 +/- 14.9. Congestive heart failure (CHF) was the reason for admission in 11 cases. The EKG findings were atrial fibrillation (AF) in 11 cases and atrial flutter in 1. Pulmonary hypertension was observed in the 17 echocardiographically documented cases. Infeccious endocarditis was diagnosed in 2 of the 4 bicuspid aortic valves. CONCLUSIONS: Congenital heart disease is not a very rare disease. In our 32 cases, 19 (59%) were ASD. CHD and AF were very common in this patology, in relation to the advanced age of this population. The echocardiography was a very useful diagnostic procedure. The 2 infective endocarditis cases between the 4 bicuspid aortic valves, is a way to remember the importance of prophylaxis.

Adolescent↗
PubMed1990

[Anatomical and radiographic study of the sinus floor distance from the alveolar crest in edentulous area of skulls].

The distance between the floor of the maxillary sinus and the alveolar crest in edentulous areas (where the 2nd bicuspid 1st and 2nd molars were previously located) were studied both anatomically and radiographically. The material consisted of 22 skulls in which 33 edentulous maxillary areas were found. Direct anatomical measurements were performed and measurements on periapical radiographs were made. The most important findings can be summarized as follows: 1. The mean distance from the alveolar crest to the floor of the sinus in locations corresponding to the 1st and 2nd molars and the 2nd bicuspid was 5.09 mm, 5.16 m.m. and 6.67 m.m. respectively. 2. Comparison of the anatomical measurements to those made on the radiographs proved that there are some differences but not statistically significant. These differences range between 0 to 5.5 m.m. for the 2nd bicuspid location, while for the 1st and 2nd molar locations they range between 0 to 2 mm.

Alveolar Process↗
PubMed1994

Valvular heart disease: the influence of changing etiology on nosology.

The many changes in classification of cardiovascular disease during the twentieth century reflect changing etiology of diseases, clinical comprehension and technological advances. In particular, the etiology of valvular heart disease has changed dramatically in the last five decades. The significant reduction of acute rheumatic fever and its sequelae, and the recognition of non-rheumatic causes of valvular disease are responsible for the metamorphosis in the etiology of valvular disorders. Valvular heart disease can be classified as follows: 1) Heritable-congenital causes of valvular heart disease e.g., floppy mitral valve with mitral valve prolapse, bicuspid aortic valve, and the Marfan syndrome; 2) Inflammatory-immunologic causes such as rheumatic fever, acquired immune deficiency syndrome, endocardial proliferative disorders, and antiphospolipid syndrome; 3) Myocardial dysfunction-ischemic cardiomyopathy, dilated or hypertrophic cardiomyopathy-resulting in valvular heart disease; 4) Diseases and disorders of other organs as causes of valvular heart disease, e.g., chronic renal failure and carcinoid heart disease; 5) Valvular heart disease related to aging: calcific aortic stenosis and mitral annular calcification; 6) Valvular disease following interventions such as valvuloplasty, valve reconstructive surgery and valve replacement; and 7) Valvular disease related to drugs and physical agents, such as chronic ergotamine use, radiation therapy and trauma. In clinical practice the most common causes of mitral regurgitation are floppy mitral valve with mitral valve prolapse, ischemic heart disease, dilated cardiomyopathy and mitral annular calcification, while the most common cause of mitral stenosis is rheumatic fever. The most common causes of isolated aortic regurgitation are bicuspid aortic valve and floppy aortic valve, while the most common causes of isolated aortic stenosis are related to the bicuspid aortic valve and the development of calcific senile aortic stenosis. The most common causes of tricuspid regurgitation are dilated cardiomyopathy, ischemic cardiomyopathy, floppy tricuspid valve with tricuspid valve prolapse and infectious endocarditis. Combined mitral and tricuspid regurgitation occur with heritable connective tissue disorders, dilated or ischemic cardiomyopathy, while the most common cause of mitral stenosis plus aortic regurgitation is rheumatic fever. Statistics obtained from cardiac surgery and necropsy may underestimate the true incidence of certain valvular diseases by selection bias. This is particularly so with valvular disease associated with significant ventricular dysfunction, or in the elderly who may not be surgical candidates, or in cases where the valvular disease is not severe enough to require surgical intervention. Recent advances in hemodynamic and imaging technology allow clinicians to define valvular structure and function and to accurately classify valvular heart disease in clinical practice.

Heart Valve Diseases↗
PubMed1991

Acute pulpal-alveolar cellulitis syndrome. V. Apical closure of immature teeth by infection control: the importance of an endodontic seal with therapeutic factors. Part 2.

During orthodontic treatment to promote eruption of maxillary and mandibular second bicuspids, a young male patient had a severe endodontic cellulitis of a mandibular bicuspid. Apexogenesis and resolution of the periapical lesion was achieved by infection control with nonspecific intracanal medication without calcium hydroxide, as stated by Das. A mild periodontal cellulitis occurred shortly thereafter and rapidly resolved. A second endodontic cellulitis, after apexogenesis without an endodontic seal, occurred shortly after completion of orthodontic treatment. This also quickly resolved, and the canal was effectively sealed. This case indicates the importance of an effective endodontic seal shortly after apexogenesis is induced by infection control. This report and others on the subject indicate that apexogenesis of nonvital permanent immature teeth by infection control is a predictable endodontic treatment procedure.

Acute Disease↗
PubMed1993

Evaluation of the effectiveness and comfort of incisive nerve anesthesia given inside or outside the mental foramen.

Thirty volunteer subjects were given bilateral injections of one-half carpule of 2% Xylocaine with 1:100,000 epinephrine to anesthetize the incisive nerve. Injections were given either inside or outside the mental foramen. Success (80/80 reading) and duration of anesthesia were verified with the Analytic Technology pulp tester. Pain and preference for either injection type were evaluated via questionnaire. The mental foramen could be located in 1 min 56.6% of the time. There was a significantly greater chance of success for injections given inside the foramen for the second bicuspid (p = 0.0422) and the canine (p = 0.015). There was no statistically significant difference in success for either type injection for the first bicuspid (p = 0.184). There was no significant difference in duration of anesthesia whether given inside or outside the foramen and no difference in pain of injection with either type. Patients had no clear-cut preference for either injection type.

Adolescent↗
PubMed2004

Gender-dependent dimorphic teeth in four species of Mesoamerican plethodontid salamanders (Urodela, Amphibia).

The tooth shapes of premaxillary and maxillary teeth of adults of four Mesoamerican salamander species (Urodela, Plethodontidae) were examined. Using scanning electron microscopy we determined whether the monocuspid teeth that are present only on the premaxillary of sexually mature males belong to the conical, unbladed, monocuspid tooth type found in urodele larvae or whether they represent morphological variations of the typical, bladed, bicuspid teeth of metamorphosed individuals. The teeth of some studied species are, in fact, unbladed and in some cases show one very reduced tip. But none of the studied teeth is per definitionem monocuspid and no tooth shows an enameloid layer between dentine shaft and enamel cap, which is always present in the teeth of early urodele larvae. The "monocuspid" teeth of adult males of Mesoamerican plethodontid salamanders have to be considered a morphological variation of the metamorphosed, bicuspid tooth type typical for metamorphosed urodeles.

Animals↗
PubMed2002

The effectiveness of increased apical enlargement in reducing intracanal bacteria.

It has been suggested that the apical portion of a root canal is not adequately disinfected by typical instrumentation regimens. The purpose of this study was to determine whether instrumentation to sizes larger than typically used would more effectively remove culturable bacteria from the canal. Forty patients with clinical and radiographic evidence of apical periodontitis were recruited from the endodontic clinic. Mandibular cuspids (n = 2), bicuspids (n = 11), and molars (mesial roots) (n = 27) were selected for the study. Bacterial sampling was performed upon access and after each of two consecutive instrumentations. The first instrumentation utilized 1% NaOCI and 0.04 taper ProFile rotary files. The cuspid and bicuspid canals were instrumented to a #8 size and the molar canals to a #7 size. The second instrumentation utilized LightSpeed files and 1% NaOCl irrigation for further enlargement of the apical third. Typically, molars were instrumented to size 60 and cuspid/bicuspid canals to size 80. Our findings show that 100% of the cuspid/bicuspid canals and 81.5% of the molar canals were rendered bacteria-free after the first instrumentation sizes. The molar results improved to 89% after the second instrumentation. Of the (59.3%) molar mesial canals without a clinically detectable communication, 93% were rendered bacteria-free with the first instrumentation. Using a Wilcoxon rank sum test, statistically significant differences (p < 0.0001) were found between the initial sample and the samples after the first and second instrumentations. The differences between the samples that followed the two instrumentation regimens were not significant (p = 0.0617). It is concluded that simple root canal systems (without multiple canal communications) may be rendered bacteria-free when preparation of this type is utilized.

Bacteria↗
PubMed2003

Patterns of endodontic care for a Washington state population.

Endodontic care, provided by 3,402 dental offices, was assessed from claims data maintained by the Washington Dental Service for 1999. Approximately 5.7 million dental procedures were provided to 880,317 patients by 2,796 general practitioners, 105 endodontists, and 494 other specialists. Of all dental services, 63,321 (1%) were endodontic procedures involving 52,911 (6%) patients. General dentists, endodontists, and other specialists performed 64.7%, 33.7%, and 1.6% of endodontic procedures, the majority of which were root canal therapy. The most frequent tooth types treated by root canal therapy were mandibular first molars (17.0%), maxillary first molars (15.2%), mandibular second molars (11.8%), maxillary second bicuspids (10.3%), maxillary second molars (9.1%), maxillary central and lateral incisors (8.8%), and mandibular second bicuspids (8.0%). Direct and indirect pulp caps by generalists and conventional retreatment and surgical therapy by endodontists made up the majority of the remaining endodontic services. Men had a greater procedure rate than women for most endodontic procedures.

Adolescent↗