provisional restoration and lab prescription

lecture given 10/8/2026

provisional restoration

a fixed or removable prosthesis designed to enhance esthetics stabilization and function for a limited period of time after which it is to be replaced by definitive prosthesis

why is a provisional restoration needed?

given for a period of time until a permanent restoration can be fabricated

to protect the prepared tooth

keep the pt comfortable

as a blueprint for the final restoration

by successful treatment with provisional restoration dentist can get the pt confidence which is an influencing factor for success in the final restoration

what are the biologic requirements of a provisional restoration?

pulp protection, periodontal health, positional stability, prevention of fracture

what are the esthetic requirements of a provisional restoration?

color compatibility, translucency, color stability

what are the mechanical requirements of a provisional restoration?

functional, retentive, ease of removal

pulp protection

during tooth prep the dentinal tubules are exposed thus provisional restoration should protect the prepared tooth from oral environment to prevent sensitivity and irritation to pulp

periodontal health

it should have good marginal fit, proper contour, and smooth surface to prevent accumulation of plaque, facilitate easy plaque removal, and maintain perio health

should NOT violate biologic width to avoid gingival inflammation

positional stability

should provide a comfortable, stable, and functional occlusal relationship by maintaining inter and intra-arch stability thereby preventing tooth migration and supra-eruption

prevention of fracture

should protect the prepared tooth surface from fracture which is commonly seen in partial coverage restorations in which margin of preparation is close to the occlusal surface of tooth and could be damaged during chewing

functional mechanical requirement

should possess good compressive and flexural strength

strength of material used for fabricating provisional restoration is always much lower than that of the definitive restoration material

serves as a blueprint for final occlusion

loss of retention mechanical requirement

it should have close adaptation to the prepared tooth surface to prevent displacement and recementation, which will increase pt vists

ease of removal

may need to be removed and recemented often- if they are well fabricated with adequate thickness and cemented with weak cement can be removed without breakage

esthetic requirement

it should match the shape, size, color, and texture of the restored tooth especially in the anterior region

color stability is also important if the provisional are to function for a prolonged period

it also serves as a guide to achieve aesthetics to the final restoration

what are the method of fabrications for provisionals?

prefab (shell)

custom made (processed

what are the materials of fabrications for provisionals?

resin- preformed (polycarbonate, cellulose acetate)

custom made- acrylics, bis-acryl composites

polycarbonate crowns

they combine micro-glass fibers with polycarbonate plastic material

it is used as a matrix material around a prepared tooth

available in shape of incisor, canine, and premolars in varying size

cellulose acetate

a thin, soft, transparent scaffold material

available in all tooth shape and different sizes

an approx size of this crown is selected from a mould guide and filled with auto-polymerizing resin of appropriate shade

inserted over the lubricated prepared tooth

what are the direct methods of fabrication?

putty matrix, vacuum shell (suck down), block temp

what are the indirect methods of fabrication?

processed provisionals

a _____ and ______ must be fabricated on the model you intend to mount for the pt with large edentulous spaces

record base

bite rim

what does a facebow mounting provide?

proper position of midline to facial landmarks as well as proper cant of adjacent teeth

what are the most important features dentists look for when choosing a lab?

high quality work (95%)

good communication

reasonable prices

easy interpersonal relationship

fast turnaround time

proximity to the lab of office (18%)

range of services

offers cutting edge technology

lab’s reputation

specializes in a restoration

offers educational programs (3%)

what questions should you answer in your lab prescription?

what are you sending?

was it mounted, if so, on what?

types of prosthetic restorative support you need- fixed, removable, CAD/CAM

materials available- specific information (shade?)

type of finish? (polished, glazed, bisque)

desired lab case turn around time

when you tell the lab what you are sending- what are some possible answers?

casts (maxillary, mandibular, master, diagnostic, pick-up, second pour, wax ups)

inter-occlusal records (blu-mousse, wax)

components (abutments, blocks, screws)

articulator (depends on calibration)

when you tell the lab what it was mounted on- what are some possible answers?

semi-adjustable articulator

fully adjustable articulator

simple hinge articulator

pin setting

brand, model

when you tell the lab the types of prosthetic restorative support you need- what are some possible answers?

porcelain fused to metal

ceramic (lithium disilicate, feldspathic, interpenetrating phase)

zirconia

casted vs pressed vs milled

when you tell the lab the materials available (specific information)- what are some possible answers?

shade- translucency, cervical shade, ND/stump shade (shade of prepared tooth), stains

t/f monolithic crowns can look natural with modification

true!

what are the types of finishes?

polished, glazed, bisque

how can you fully utilize the prescription?

fully communicate the desired result

use all types of communication tools- writing, diagrams, photos, designed casts, shade sources/objects

writing down is the best tool

proof of communication

what should a prescription contain?

name, age, gender

date of request

detailed description of the desired prosthesis

specific materials/chemical composition to be used (metal, acrylic, ceramic)

shade (number and specific guide)- diagram, photo, formed restoration

desired occlusion- accurate casts, interocclusal record, articulator settings

what are some communication concerns?

lack of recognition by the dental team

lack of effective communication in the lab prescription

lack of knowledge by the dentist of technical procedures

what is the lab’s responsibility?

contact the dentist when directions are not clear or are inappropriate for the desired products

dental labs should include a sticker certificate authenticating the materials used in the fabrication of all prostheses in the box returned to the dentist

since dental prostheses are medical devices, information ensuring safety, such as material/composition/and manufacturer should be included

what are the top 5 reasons dentists change labs?

inconsistent quality/technical problems

prices were higher than they wanted to pay

delayed turnaround time

poor relationship/poor communication

prescriptions not being thoroughly or carefully read and filled

master casts from a pick up impression

will be a solid cast- no removable dies

will fit a soldering casting

will show the relation of the soft tissue to the casting for esthetic purposes as well as for the design of the pontic

must be correctly mounted for porcelain application

tldr take aways from this lecture

do not discard impressions until your restoration is inserted

preoperative diagnostic casts are always helpful

if you’re not sure- ask

all bubbles are bad… positive or negative