will anyone please help me out of those confusing questions?
an endodontically treated permanent mandibular first molar has incipient lesions on its mesia and distal surfaces. during previous treatment, a minimal amount of tooth structure was removed, the appropriate treatment for this tooth is
a MOD amalgam
B MOD cast gold inlay
C MOD cast gold onlay
D 3/4
E full crown
what's shim stock?used to evaluating centric occlusion on a newly placed onlay restoration?
when using an occlusal separator(what's it?),a practitioner can expect which of the following types of TMJ disorders ro respongd most favorably?
a chronic dislocation
b muscle spasm
c capsular fibrosis
d unilateral condylar hyperplasia
a practitioner pickles gold alloy restorations by heating them to redness and plunging them into an acid bath.this precedure can result in which of the following?
c warpage of the restoration?
d surface foughness of the restoration.
key is c.why?
a dentist will reline an extension-base removable partial denture.which of the following should this dentist use to establish preper placement an the impression stage.
a finger pressure to the rests and indirect retainer
b finger pressure to the base area only
which one?why?
which of the following foor surfaces is the most likely to be strip-perforated during canal instrumentation of he mesial root of a mandibular first molar?
a facial
b lingual
c mesial
d distal
why? and what's strip-perforated?
when is the appropriate time to take the first bite-wing radiagraphs of a clinically caries-free child?
a when spaces between the posterior teeth have closed.
what is this x-ray check for?
which condition is characterized by lesions in the centarl nervous system that manifests itself as various types of neuromuscular dysfunction?
a cerebral palsy
b hyperkinesis
which one?
a patient's permanent tooth crown fractures,creating a small(1mm) pulp exposure for about 30minutes.which of the following pulp therapies is the most appropriate for this patient?
b direct pulp capping with calcium hydroxide.
that's the key.
what's the time limit for direct pulp capping?
a 15 year old patient has all teeth present, normal occlusion, molar toots not fully calcified.the mandibular right fist molar has a pathologic pulp exposure.endodontics failed and the toothe must be extracted.the subsequent treatment indicated is to
a place a space maintainer
b place a removable partial denture.
key is a,why not b?
mesioangular extopic eruption of a permanent maxillary first molar causing resorptong of the distal surfaces of the roots of the primary second molar should be treated by：
c： tipping the permanent first molar distally using a sepatating device
what's the device?how does it work on an erupting tooth?i mean,what if this tooth is not clinically visible yet?
why is propranolol contraindicated in a patient with cardiac arrhythmia?
a previously inserted silicate cement restoration is coated with a protective medium when a rubber dam is applied in order to prevent
a expansion
b syneresis
c desiccation
d water sorption
which one?and why?
in what situation can a proximal cavity be prepared and be limited to the involved proximal surface?
dental development in a child,as measured by tooth and root formation,proceeds as a rate which is
a independent on left and right sides of the mouth
b independent of the degree of skeletal development.
which one?why?
does compound odontoma have inductive influence on the mesenchymal tissues?
how?
a periodontal pocket can be seen radiographically on which of the following surfaces?
a mesial
b distal
c both
d none
key is d,why?
a patient wearing complete dentures has trouble swallowing.what is the most probable cause?
a insuffient interocclusal space
b excessive interocclusal space
which one?why?
mechanical properties of which of the following base metal alloys can be improved by heat treatment?
a co-cr
b co-ni-cr
c ni-cr
d none(key) why?
the biologic requirements of an anterior 3/4crown include：
a： maintainng the health of the investing tissues
b： a staple form of axial and incisal grooves that prevent axial spreading.
what does b mean?
exposure of a stone cast to tap water should be minimized because
b eroding of the cast will result
how????
which of the following conditions hasten the destruction of a znpo4 cenment film used for luting?
a abrasion(key)
how could the luting be abrased?
the nonrigid connector may be used in fixed bridges in those cases involving
a long span bridges replacing two or more teeth
b short span bridge preplacing one missing toothe where the prepared abutment teeth are not in parallel alighment
b is key.but why not a?
as the denture base settles due to lower ridge resorption,the effect is to
a make the chin recede
b eliminated the mentolabial sulcus
c make the nasolabial fold deepen
d make the chin appear protruded
which two?
which of the following clinical situations are contraindicated for use of a partial veneer crown?
a short teeth
b long teeth
c teeth too small or thin for accurate positioning of proximal grooves
d teeth with prximal contact aresa at the gingival margin
e teeth in a mouth with alow caries index
key is a,c,d
why d?
which characterize nitrous oxide?
a good analgesia
b poor skeletalmuscle relaxation
c rapid induction in concentrations of 80%
why a?
many studies show that nitrous oxide does not have good analgesia,in a study,almost 1/3 labouring women said nitrous oxide has not any effect.
the contact area on the distal surface of a maxillary first premolar should be placed in the
key: occlusal third of the proximal surface with the lingual embrasure greater than the facial embrasure
why occlusal third?should it be middle and occlusal ?
the only area where cavosurface margings or wall juctions of an onlay cavity are never beveled or planed is where?
the facial and lingual cavosurface margins?
when and where can we use zinc choloride-impregnated cord?
which of the following may cause excessively dense radiographs?
a overexposure
b underdevelopment
c backwards placement of the film
d use of excessive milliampere seconds
e a longer cone without adjustment in exposure time
what is the key?
and why?
the primary purpose of a plaster index of the occlusal surfaces of a maxillary denture before removing the denture from the articulator and cast is to
a preserve the face-bow transefer
why ?and how??
to maintain and pretect the health of gingival tissues , correct contoour of a crown is important in which of the following areas?
a middle third
b infragulge or gingival third
c height of contour of suprabulge
d interproximal gingival areas
b,d are keys.why?????
the facial surface of the maxillary right canine contains a lesion, the cervical margin of which is slightly beneath the gingiva,3mm of attached healthy gingiva remains. a composite resin will be uesed,the indicated method of approach should be to
2 retract the gingiva wiht a clamp and rubber dam
3 with retraction cord
how?why not 3?because of the moisture which cannot be controlled by retraction cord?
sulfonamides and trimethoprim are synergistic bacteriostatic agents because in bacteria they 1 interfere sequentially with folinic acid production.
2 both inhibit folic acid synthesis
which one?
from wikipedia:In bacteria, antibacterial sulfonamides act as competitive inhibitors of the enzyme dihydropteroate synthetase, DHPS. DHPS catalyses the conversion of PABA (para-aminobenzoate) to dihydropteroate, a key step in folate synthesis.
the nonrigid connector may be used in construction of a fixed partial denture only when the span is
1 shor and the supoorting alveolus is extensively reduced.
2 short and the supporting alveolus is not extensively reduced.
3 long and the supoorting alveolus is extensively reduced.
4 long and the supporting alveolus is not extensively reduced.
which and why?
loops and helices are used in arch wires primarily to
1 increase flexibility of the wire
2 hold soft tissues away from orthodontic brackets
will attached gingiva increase after properly performed scaling and root planing?why?
which of the following factors should be considered in electing to perform a gingivectomy rather than a periodontal flap?
1 presence of gingival edema
2 pocket depth
3 presence of subgingival calculus
4 need for access to bone
5 amount of existing attached gingiva
which one(s),and why?
which of the following severely conplicates performing a distal wedge in the area of a mandibular molar?
1 a sital root fluting
2 an infrabony pocket distal to the molar
3 a long retromolar pad that is primaryly attached gingiva
4 a sharply ascending ramus that limits space distal to the molar
