First observation and Dalitz analysis of the D0-->K(0)Setapi(0) decay.

Using 9.0 fb(-1) of integrated luminosity in e(+)e(-) collisions near the Upsilon(4S) mass collected with the CLEO II.V detector we report the first observation of the decay D0-->K(0)(S)etapi(0). We measure the ratio of branching fractions, BR(D0-->K(0)(S)etapi(0))BR / (D0-->K(0)(S)pi(0))=0.46+/-0.07+/-0.06. We perform a Dalitz analysis of 155 selected D0-->K(0)(S)etapi(0) candidates and find leading contributions from a(0)(980)K(0)(S) and K(*)(892)eta intermediate states.

Measurement of B(D+-->K(*0)l(+)nu(l)).

Using 13.53 fb(-1) of CLEO data, we have measured the ratios of the branching fractions R(+)(e),R(+)(mu) and the combined branching fraction ratio R(+)(l), defined by R(+)(l)=[B(D+-->K(*0)l(+)nu(l))]/[B(D+-->K-pi(+)pi(+))]. We find R(+)(e)=0.74+/-0.04+/-0.05, R(+)(mu)=0.72+/-0.10+/-0.05, and R(+)(l)=0.74+/-0.04+/-0.05, where the first and second errors are statistical and systematic, respectively. The known branching fraction B(D+-->K-pi(+)pi(+)) leads to B(D+-->K(*0)e(+)nu(e))=(6.7+/-0.4+/-0.5+/-0.4)%, B(D+-->K(*0)mu(+)nu(mu))=(6.5+/-0.9+/-0.5+/-0.4)%, and B(D+-->K(*0)l(+)nu(l))=(6.7+/-0.4+/-0.5+/-0.4)%, where the third error is due to the uncertainty in B(D+-->K-pi(+)pi(+)).

Experimental investigation of the two-photon widths of the chi(c0) and the chi(c2) mesons.

Using 12.7 fb(-1) of data collected with the CLEO detector at CESR, we observed two-photon production of the cc states chi(c0) and chi(c2) in their decay to pi(+)pi(-)pi(+)pi(-). We measured gamma(gammagamma)(chi(c))xB(chi(c)-->pi(+)pi(-)pi(+)pi(-)) to be 75+/-13(stat)+/-8(syst) eV for the chi(c0) and 6.4+/-1.8(stat)+/-0.8(syst) eV for the chi(c2), implying gamma(gammagamma)(chi(c0)) = 3.76+/-0.65(stat)+/-0.41(syst)+/-1.69(br) keV and gamma(gammagamma)(chi(c2)) = 0.53+/-0.15(stat)+/-0.06(syst)+/-0.22(br) keV. Also, cancellation of dominant experimental and theoretical uncertainties permits a precise comparison of gamma(gammagamma)(chi(c0))/gamma(gammagamma)(chi(c2)), evaluated to be 7.4+/-2.4(stat)+/-0.5(syst)+/-0.9(br), with QCD-based predictions.

Rate measurement of D(0)-->K+pi(-)pi(0) and constraints on D(0) -- D(0) mixing.

We present an observation and time-integrated rate measurement of the decay D(0)-->K(+)pi(-)pi(0) produced in 9 fb(-1) of e(+)e(-) collisions near the Upsilon(4S) resonance. The signal is inconsistent with an upward fluctuation of the background by 4.9 standard deviations. We measured the time-integrated rate of D(0)-->K(+)pi(-)pi(0) normalized to the rate of D(0)-->K(+)pi(-)pi(0) to be 0.0043(+0.0011)(-0.0010) (stat)+/-0.0007 (syst). This decay can be produced by doubly Cabibbo-suppressed decays or by the D(0) evolving into a D(0) through mixing, followed by a Cabibbo-favored decay to K(+)pi(-)pi(0). We also found the CP asymmetry A = (9(+25)(-22))% be consistent with zero.

Search for B --> tau(nu) and B --> K(nu)nu.

We report results of a search for B-->tau(nu) in a sample of 9.7 x 10(6) charged B meson decays. We exclusively reconstruct the companion B decay to suppress background. We set an upper limit on the branching fraction B(B-->tau(nu))<8.4 x 10(-4) at 90% confidence level. We also establish B(B+/--->K+/-nu(nu))<2.4 x 10(-4) at 90% confidence level.

Measurements of the mass, total width, and two-photon partial width of the eta(c) meson.

Using 13.4 fb(-1) of data collected with the CLEO detector at the Cornell Electron Storage Ring, we have observed 300 events for the two-photon production of ground-state pseudoscalar charmonium in the decay eta(c)-->K(0)(S)K-/+pi(+/-). We have measured the eta(c) mass to be [2980.4+/-2.3 (stat)+/-0.6 (syst)] MeV and its full width as [27.0+/-5.8 (stat)+/-1.4 (syst)] MeV. We have determined the two-photon partial width of the eta(c) meson to be [7.6+/-0.8 (stat)+/-0.4 (syst)+/-2.3 (br)] keV, with the last uncertainty associated with the decay branching fraction.

Dual-tray impression technique for implant-retained overdentures.

Accurately recording implant positions and the edentulous areas during the fabrication of implant-retained overdentures can be a difficult task. A modification of the dual or split-tray technique is suggested for implant-retained overdentures. This procedure permits the construction of the prosthesis on one master cast and the use of two impression materials with different properties incorporated into a single impression to correspond with the needs of specific anatomic areas of the mouth.

Spark erosion implant-supported overdentures: clinical and laboratory techniques.

Overdentures can be utilized effectively in treatment plans involving implants. Usually soft tissue support is necessary, which requires a conventional denture base. Implant-supported overdentures do not require conventional denture base extension unless necessitated by functional or esthetic considerations. With fixed-detachable hybrid dentures, flanges can often interfere with home care procedures. Spark erosion overdentures meet the requirements for esthetics, phonetics, retention, and support and also allow accessibility for proper patient oral hygiene. This article reviews the advantages and disadvantages of the spark erosion overdenture and provides guidelines for the fabrication of this type of prosthesis.