Comparison of mometasone furoate administered by metered dose inhaler with beclomethasone dipropionate.

This study compared the efficacy and safety of mometasone furoate (MF) administered by metered dose inhaler (MDI) 56, 200 or 500 pg b.i.d., with beclomethasone dipropionate (BDP) 168 microg b.i.d. and placebo. Adult patients (n=395), with moderate persistent asthma (FEV1 50-90% of predicted normal), previously maintained on inhaled corticosteroids, were enrolled at 16 centres in a four-week, randomised, double-blind, double-dummy, multicentre, dose-ranging trial. At endpoint, FEV1 was significantly improved (p<0.01) with MF-MDI 56, 200 and 500 microg b.i.d., as well as with BDP (6%, 13%, 14% and 4%, respectively), compared with placebo (-12%). Mean change in FVC, FEF2575%, and a.m. and p.m. peak expiratory flow rate (PEFR) were also significantly improved for all active treatment groups at endpoint compared with placebo. Asthma symptoms and quality of life (SF-36) related to physical functioning improved with active treatments relative to placebo. All doses of MF-MDI were well tolerated. Treatment with MF-MDI 200 pg b.i.d. was superior to BDP MDI 168 microg b.i.d. or MF-MDI 56 microg b.i.d., with no additional benefit derived from a higher MF-MDI 500 microg b.i.d. dose. MF-MDI was well tolerated, with superior efficacy compared with BDP MDI in these patients with moderate persistent asthma.

Irrigation rates and handpieces used in prosthodontic and operative dentistry: results of a survey of North American dental school teaching.

PURPOSE: A data baseline on dental cutting methodologies was established by means of a survey of North American dental school teaching. MATERIALS AND METHODS: Sixty-four North American dental schools were surveyed regarding their recommendations on handpiece usage and coolant flow rates in fixed prosthodontics and operative dentistry. RESULTS: High-speed handpieces were the instruments of choice for tooth preparation in fixed prosthodontics. In operative procedures, recommendations for sole use of the high-speed, the low-speed, or both handpiece types were more uniform. CONCLUSIONS: North American dental schools advocate greater use of high-speed than low-speed handpieces. Although the use of high-speed handpieces predominate in schools in Canada and Puerto Rico, there is a proportionately higher use of low-speed handpieces than in US dental schools. Few (approximately 1 in 5) schools made recommendations on coolant flow rates during cutting procedures.

Enhanced dental cutting through chemomechanical effects.

BACKGROUND: Previous studies have shown that certain surface-active agents--compounds that reduce interfacial tension--in a dental handpiece's irrigation water can enhance cutting rates, or CRs. This study evaluated these effects under test conditions simulating dental practice. METHODS: The authors used a self-contained cutting system with a digitally controlled handpiece speed, torque and water flow rate to cut machinable glass ceramic (Macor, Corning Inc.) with medium-grit diamond burs and cross-cut fissure carbide burs under a load of 147.5 grams and 22 milliliters per minute coolant flow rate using water with mouthwash (Scope, Procter & Gamble) additions. They used six burs for each irrigant mixture to make three 5-millimeter edge cuts through 13 mm of Macor; CRs were quantified as the time necessary to transect the Macor cutting substrate. RESULTS: Additions of small amounts of mouthwash to the coolant water accelerated the CR for both carbide and diamond burs. The CRs for carbide burs in millimeters per second were distilled water, 0.21; 1:2.5 mouthwash:distilled water mixture, 0.12; 1:5 mixture, 0.64; and 1:10 mixture, 0.66. The CR differences for the 1:5 and 1:10 mixtures were significant (P < .001). The CRs for diamond burs in millimeters per second were distilled water, 0.09; 1:1 mouthwash:distilled water mixture, 0.13; 1:2.5 mixture, 0.16; 1:5 mixture, 0.21; and 1:10 mixture, 0.18. When it came to the diamond burs, the CR differences between water and the mouthwash:distilled water mixtures were significant (P < .001). The authors found that the mouthwash additions ensured higher CRs compared with those for water alone over the entire cutting regimen; that is, while the CRs for both carbide and diamond burs dropped with prolonged cutting with water irrigation, the addition of mouthwash resulted in the burs' cutting faster and for longer than with water alone. CONCLUSION: Adding small amounts of mouthwash to the coolant water significantly enhanced cutting by diamond and carbide burs and maintained higher CRs with prolonged cutting. CLINICAL IMPLICATIONS: Making low additions of mouthwash (1:5 and 1:10 mouthwash:distilled water mixtures) to the handpiece irrigant system can lead to two- to threefold increase in the dental diamond and carbide bur cutting rate compared with that for water alone.

Cutting efficiency of three diamond bur grit sizes.

BACKGROUND: Tooth preparation requires safe, efficient and rapid cutting, and diamond burs routinely are used for extracoronal preparation and gross tooth reduction. Coarser-grit diamond burs often are used for gross tooth reduction, with tooth surface finishes being sacrificed for the presumed greater cutting rates, or CRs, of the coarser diamond burs. The authors compared the CRs of medium-, coarse- and super-coarse-grit diamond burs. METHODS: The authors used a self-contained dental treatment system with digitally controlled handpiece speed, torque and water flow rate to cut a machinable glass ceramic cutting substrate with medium-, coarse- and super-coarse-grit diamond burs from the same manufacturer under a load of 147.5 grams (0.9 kilonewton at the bur tip) and a coolant flow rate of 22 milliliters per minute. They made three cuts through 13-millimeter bars of the cutting substrate with six diamond burs of each grit size. They determined CRs as the transection time per millimeter and analyzed CR data by one-way analysis of variance and post hoc Scheffé tests. RESULTS: The authors found no statistically significant difference in CR (P > .05) between the three diamond bur grit sizes for the first (13 mm) cuts. When they compared the three cuts (39 mm total cut length), they found no difference (P > .05) between CRs for coarse- and super-coarse-grit diamond burs, but they did find that the super-coarse-grit diamond burs cut faster than the medium-grit diamond burs (P < .01). CONCLUSION: Differences in CR for the three diamond bur grit sizes are due to the greater decrease in CR for the medium-grit diamond burs (50 percent) compared with the CRs of the coarse- and super-coarse-grit diamond burs (35 percent and 25 percent, respectively) over the total cutting period. CLINICAL IMPLICATIONS: Coarser-grit diamond burs may be useful for extensive gross tooth preparations, but dental professionals should be aware of the associated effects of the coarser grit on surface finish, heat generation and enamel damage.

Handpiece coolant flow rates and dental cutting.

High-speed handpieces incorporate water coolant sprays to remove cutting debris and minimize thermal insult to the pulp. Little data exists on optimal coolant flow rates during clinical procedures. This study compared the effect of different coolant flow rates on diamond stone cutting efficiency. Cutting studies were performed on Macor machinable ceramic using a previously developed test regimen--a KaVo high-speed handpiece at a cutting force of 91.5 g (0.9 N). Cutting was performed with round end tapered medium grit diamond stones under cooling water flow rates of 15, 20, 25, 30 and 44 ml/min, with cutting rates determined as the time to transect the 13 mm square cross-section of the Macor bar. Each bur was used for five cuts, with six burs used for each flow rate, for a total of 150 measurements. The data were analyzed by one-way ANOVA with a post hoc Scheffé test. The cutting studies indicated that diamond stone cutting rates increased with higher coolant flow rates over the range of 15-44 ml/min. The data suggest that higher coolant flow rates promote cutting efficiency.

Dental cutting with diamond burs: heavy-handed or light-touch?

PURPOSE: The cutting efficiency of diamond dental burs using different handpiece loads was evaluated against simulated enamel, a machinable glass ceramic (Macor). MATERIALS AND METHODS: An ultra-high-speed dental handpiece was mounted in a frictionless bearing so that the pressure applied at the contact interface between the dental bur and the cutting substrate was controlled. One type of coarse- and two types of medium-grit diamond burs were studied. Handpiece loads of 44, 91.5, and 183 g were applied at the bur/Macor interface, and cutting efficiency was determined as the amount of Macor removed in ten 30-second-duration cuts that were 4 mm in length. The data were analyzed by one-way ANOVA and a post-hoc Scheffé test at an a priori alpha = 0.05. RESULTS: Cutting efficiency depended on both the diamond grit of the bur and the load applied to the handpiece. CONCLUSIONS: The pressure used by most dentists, about 100 g at the bur tip, appears to be optimal for medium-grit burs. If the pressure applied to the handpiece is markedly increased, there was no increase in cutting efficiency for medium-grit burs. In contrast, an increased handpiece pressure raises the cutting efficiency of coarse-grit burs but the effect of this enhanced rate of cutting on the pulpal tissues is uncertain. Cutting efficiency also appeared to be dependent on debris accumulation between the diamond chips.

Irrigating solution and pressure effects on tooth sectioning with surgical burs.

OBJECTIVE: The purpose of this study was to determine the influence of the applied load on the handpiece, type of cooling agent, and type of tooth on surgical tooth dissection with a tapered crosscut fissure bur. STUDY DESIGN: Cutting studies were performed at handpiece loadings of 295 and 590 g through use of an oral surgery straight handpiece, tapered crosscut fissure burs, and an established cutting regimen. Extracted molars were dissected under irrigation with water, 0.9% saline solution, and lactated Ringer's solution at constant flow rates of 15 and 25 mL/min. Cutting efficiencies were analyzed by 1-way analysis of variance and Scheffé tests. RESULTS: No difference in cutting efficiency was found at low loads under irrigation with water or saline solution, but under irrigation with lactated Ringer's solution, a higher cutting efficiency was found (P < .05). There was no difference in cutting efficiency for lactated Ringer's solution and saline solution at high loads, but both cut more efficiently than water (P < .01). CONCLUSIONS: Saline solution is a useful coolant/irrigant for the dissection of teeth under most conditions, but lactated Ringer's solution might be beneficial with respect to cutting efficiency when lower handpiece loads are required.

Tooth stabilization and splinting before and after periodontal therapy with fixed partial dentures.

The design and use of fixed partial dentures as a definitive restoration to stabilize and splint teeth have been reviewed. The provisionalization of the splinted patient has been described as it is incorporated into the treatment plan of patients with a weakened periodontium. The current controversy of incorporating implants in the patient requiring splinting was discussed, and recommendations are made. Dentists are encouraged to explain all potential ramifications of splinting with fixed partial dentures, including cost, frequency of office visits, and potential alterations or remakes of the prosthesis should physiologic demands surpass the capabilities of the remaining teeth.

Comparison of sectioning rates among carbide and diamond burs using three casting alloys.

PURPOSE: This study compared the sectioning rates of commercially available high noble, noble, and base metal casting alloys using two new cross-cut tungsten carbides specifically manufactured for alloy sectioning and two medium grit diamond burs. MATERIALS AND METHODS: Rectangular bars cast from a base metal alloy (Ni-Cr-Mo-Be), a noble alloy (Pd-Cu-Au), and a high noble alloy (Au-Ag-Cu-Pd) were sectioned under controlled conditions. Two types of cross-cut tungsten carbide and two types of medium grit diamond burs were tested using a high-speed handpiece under a coolant flow rate of 20 mL/min and an applied load at the bur tip of 0.9 N (91.5 g). Three 4-mm cuts were made through the alloy specimens using six burs of each type. The time required for Cuts 1, 2, and 3 was recorded, and sectioning rates in millimeters per minute were calculated as a relative measure of cutting efficiency. For each alloy, the total time required for the three cuts was analyzed using one-way analysis of variance (one-way ANOVA) and Scheffé tests (alpha = 0.05) to determine differences in sectioning rate among bur types. RESULTS: In general, mean sectioning rate for Cut 1 through Cut 3 decreased with longer use of the bur. Regarding total sectioning times, the carbide burs sectioned the base metal alloy significantly faster (P < .001) than the diamond burs. However, diamond burs sectioned the high noble alloy significantly faster (P < .001) than the carbide burs. Diamond burs also sectioned the noble alloy more quickly than the carbide burs, but the difference was not statistically significant. CONCLUSIONS: The cross-cut tungsten carbide burs should be used to section the base metal alloy but the medium grit diamond burs should be used to section the high noble alloy.

Dental burs--what bur for which application? A survey of dental schools.

PURPOSE: The purpose of this study was to survey North American dental schools regarding recommendations for rotary instrumentation for fixed prosthodontic and operative procedures at the predoctoral and postgraduate level. MATERIALS AND METHODS: A 25-question survey was sent to 64 North American dental schools, of which 15 questions specifically related to rotary instrument recommendations. One questionnaire was addressed to the individual at each school having administrative responsibility for teaching tooth preparation techniques. A high response rate was assured by follow-up telephone calls and faxes. The distributions of bur recommendations for both predoctoral and advanced prosthodontic programs were analyzed by chi-squared tests at an a priori alpha = 0.05. RESULTS: Completed surveys were received from 58 of 64 dental schools, a response rate > 90%. Medium grit burs predominate in predoctoral education for gross tooth reduction for fixed prosthodontics, whereas coarse grit burs predominate at the graduate level (p < .05). The use of the diamond bur alone predominates for axial wall refinement, whereas the use of carbide burs or carbide burs in combination with diamond burs prevails for marginal refinement (p < .05). In predoctoral operative dentistry, recommendations for cavity outline form were similar at all dental schools (p > .05) and were principally tungsten carbide (WC) burs. Carbide burs are the instrument of choice for internal walls, but the WC bur alone or in combination with diamond burs is preferred for refining composite margins (p < .05). CONCLUSIONS: There is a broad consensus within North American dental schools on rotary instrumentation used by dental students. There is a greater use of coarser grit burs for gross tooth reduction in fixed prosthodontics at the postgraduate than predoctoral level.

Oral rehabilitation of a child with primary failure of tooth eruption.

This article describes the prosthetic evaluation and treatment of a 10-year-old female patient with primary failure of tooth eruption. This case is unique in that the failure of eruption affected both the deciduous and permanent dentition in all quadrants, in the absence of any other systemic abnormalities. After diagnostic articulation and a thorough discussion of the treatment with the patient and her parents, complete maxillary and mandibular overdentures were fabricated. The process followed with this preadolescent patient to ensure maximum compliance, success, and encouragement toward a positive attitude in wearing complete dentures is reported.

Dental cutting: the historical development of diamond burs.

This brief history of the dental diamond bur is intended to provide both a historical perspective and an evaluation of the current state of bur technology. An understanding of the origins of dental diamonds and the issues facing manufacturers transforms the dentist from a simple user into an informed consumer. The author contends that this can improve dental care and enable the dentist to collaborate with manufacturers in developing improved dental burs.

Combined orthodontic and prosthetic therapy. Special considerations.

The adult patient may present with a complex medical and dental history. Comprehensive treatment planning with appropriate consultation among the restorative dentist and other dental specialists is a prerequisite for a successful treatment outcome. This article reviewed the role of orthodontic treatment in the restoration of the partially edentulous patient. The case illustrations presented show the value of collaborative efforts in a multidisciplinary team approach. Although there may be initial reluctance on the part of some patients to seek multiple specialty consultations, the rewards are great for the patient and the dentists who subscribe to this treatment philosophy.

Assessing the cutting efficiency of dental diamond burs.

This study measured the cutting efficiencies of 15 types of roundend tapered conventional and disposable diamond burs. The results showed that disposable diamond burs had cutting efficiencies that were comparable to those of conventional (multiuse) diamond burs; their use should reduce the risk of clinical cross-infection.

Comparison of the bronchodilatory effects of cetirizine, albuterol, and both together versus placebo in patients with mild-to-moderate asthma.

BACKGROUND: Many potential users of the H1 antihistamine cetirizine are asthmatic and may be using inhaled albuterol. This study was conducted to assess the possible bronchodilatory effect of cetirizine in patients with mild-to-moderate asthma and to determine whether cetirizine interacts with albuterol. METHODS: In a randomized, double-blind, placebo-controlled, crossover study, the effects on pulmonary function of 5, 10, and 20 mg oral doses of cetirizine with and without inhaled albuterol (180 micrograms) were determined in 12 patients at 11 time points over 8 hours. The primary measure of efficacy was forced expiratory volume in 1 second (FEV1). RESULTS: Cetirizine with or without albuterol significantly increased FEV1, peak expiratory flow rate, and forced expiratory flow rate between 25% and 75% of vital capacity relative to baseline and placebo but did not have a significant effect on forced vital capacity. The effect of 20 mg of cetirizine on FEV1 was generally greater than that of 10 or 5 mg, but the difference was statistically significant only at the 30-minute time point (p < 0.05). All three cetirizine doses produced significantly greater increases than placebo in FEV1 and forced expiratory flow rate between 25% and 75% of vital capacity for 8 hours and in peak expiratory flow rate for 7 hours (p < 0.02). Albuterol alone had a significant effect on the four pulmonary function variables from 1 to 5 hours after baseline (p < 0.05), which is consistent with albuterol's recommended dosing frequency of every 4 to 6 hours. Albuterol alone increased FEV1 significantly more than 5 mg of cetirizine alone but not 10 mg or 20 mg of cetirizine alone at 60, 90, and 120 minutes after baseline, but all three doses of cetirizine increased FEV1 significantly more than albuterol 7 and 8 hours after baseline (p < 0.05), indicating that the bronchodilatory action of cetirizine lasts longer than that of albuterol. Cetirizine neither potentiated nor inhibited the bronchodilatory action of albuterol, but the two drugs appeared to have an additive bronchodilatory effect. None of the cetirizine treatments caused a worsening of pulmonary function, and all were well tolerated. CONCLUSIONS: Cetirizine has a significant bronchodilatory effect in patients with mild-to-moderate asthma and can be used to treat concomitant conditions (e.g., allergic rhinitis) without concern that it will interfere with the bronchodilatory effect of albuterol or cause worsening of asthma by itself.

A comparison of imaging techniques in patients with chronic sinusitis (X-ray, MRI, A-mode ultrasound).

Thirty-five patients age 9 to 67 were evaluated for chronic sinusitis by history, physical and laboratory examination, and imaging techniques (X-ray, magnetic resonance imaging (MRI) and flexible rhinoscopy). MRI was the most predictive. To establish the diagnosis of sinusitis, it was more sensitive than plain X-ray for intrasinus disease. Findings of edema, erythema, and drainage on flexible rhinoscopy were consistent with chronic sinusitis and were confirmed by MRI and sinus X-rays in 41% of the cases. Nasal smears for polymorphonuclear cells and eosinophils were suggestive of a diagnosis of chronic sinusitis, but other laboratory tests (CBC, sedimentation rate, quantitative immunoglobulins, total IgEs) were of very limited value in the diagnosis of chronic sinusitis.