Aesthetic Dentistry

[sushantpatel_doc]

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[sushantpatel_doc]

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[Anonymous]

sushantpatel_doc wrote:

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looks good but what could be the stability of such a big repair of the broken incisor?

perhaps the patient may require RCT followed by a crown .

veerendra

        

[charmi_shah]

Sir could veneer be successful treatment for this case?

Regards.

        

[sushantpatel_doc]

In this case the patient has to be extra careful..and not much force acts over the upper anteriors…so i think such a restoration will be stable for years..

        

[Anonymous]

charmi_shah wrote:

Sir could veneer be successful treatment for this case?

Regards.

case selection is very important for veneers. if there is less support for the veneers than they may come out very soon. From the images I feel that endo , followed by post and core ( at least for the patients left central) followed by a crown would be required.

regards,

veerendra

        

[drmithila]

Age: There is a direct correlation between tooth color and age. Over the years, teeth darken as a result of wear and tear and stain accumulation. Teenagers will likely experience immediate, dramatic results from whitening. In the twenties, as the teeth begin to show a yellow cast, teeth-whitening may require a little more effort. By the forties, the yellow gives way to brown and more maintenance may be called for. By the fifties, the teeth have absorbed a host of stubborn stains which can prove difficult (but not impossible) to remove.

Starting color: We are all equipped with an inborn tooth color that ranges from yellow-brownish to greenish-grey, and intensifies over time. Yellow-brown is generally more responsive to bleaching than green-grey.

Translucency and thinness: These are also genetic traits that become more pronounced with age. While all teeth show some translucency, those that are opaque and thick have an advantage: they appear lighter in color, show more sparkle and are responsive to bleaching. Teeth that are thinner and more transparent – most notably the front teeth – have less of the pigment that is necessary for bleaching. According to cosmetic dentists, transparency is the only condition that cannot be corrected by any form of teeth whitening.

Eating habits: The habitual consumption of red wine, coffee, tea, cola, carrots, oranges and other deeply-colored beverages and foods causes considerable staining over the years. In addition, acidic foods such as citrus fruits and vinegar contribute to enamel erosion. As a result, the surface becomes more transparent and more of the yellow-colored dentin shows through.

Smoking habits: Nicotine leaves brownish deposits which slowly soak into the tooth structure and cause intrinsic discoloration.

Drugs / chemicals: Tetracycline usage during tooth formation produces dark grey or brown ribbon stains which are very difficult to remove. Excessive consumption of fluoride causes fluorosis and associated areas of white mottling.

Grinding: Most frequently caused by stress, teeth grinding (gnashing, bruxing, etc.) can add to micro-cracking in the teeth and can cause the biting edges to darken.

Trauma: Falls and other injuries can produce sizable cracks in the teeth, which collect large amounts of stains and debris.

 

        

[Drsumitra]

BRIEF HISTORICAL BACKGROUND
For more than 250 years, clinicians have written about the placement of posts in the roots of teeth to retain restorations.1 As early as 1728, Pierre Fauchard described the use of “tenons,” which were metal posts screwed into the roots of teeth to retain bridges.1 In the mid-1800s, wood replaced metal as the post material, and the “pivot crown,” a wooden post fitted to an artificial crown and to the canal of the root, was popular among dentists.1 Often, these wooden posts would absorb fluids and expand, frequently causing root fractures.2 In the late 19th century, the “Richmond crown,” a single-piece post-retained crown with a porcelain facing, was engineered to function as a bridge retainer.2 During the 1930s, the custom cast post-and-core was developed to replace the one-piece post crowns. This procedure required casting a post-and-core as a separate component from the crown.2 This 2-step technique improved marginal adaptation and allowed for a variation in the path of insertion of the crown.1

CAUSES OF POST-RETAINED CROWN FAILURE
The failure of post-retained crowns has been documented in several clinical studies (Figure 1).3 Many of these studies indicate that the failure rate of restorations on pulpless teeth with post-and-cores is higher than that for restorations of vital teeth.3

 Restorative failure of an all-ceramic crown on the maxillary right central occurring after endodontic treatment. A minimum of a 1 mm collar on sound tooth structure is required for a ferrule design.

 After determining the desired post channel length (one half to two thirds length of canal), the gutta-percha was removed with a series of pre-shaping instruments (Gates Glidden [SybronEndo]) (Rebilda post reamer [VOCO]).
Several main causes of failure of post-retained restorations have been identified, including: recurrent caries, endodontic failure, periodontal disease, post dislodgement, cement failure, post-core separation, crown-core separation, loss of post retention, core fracture, loss of crown retention, post distortion, post fracture, tooth fracture, and root fracture.4-6 Also, corrosion of metallic posts has been proposed as a cause of root fracture.7

A COMPARISON OF CURRENT POST SYSTEMS

. The channel preparation for a prefabricated fiber-reinforced post was performed using a color-coded drill (Rebilda post drill [VOCO]), establishing the desired intraradicular length and size for the selected post.

The pre-selected fiber-reinforced composite post (Rebilda post [VOCO]) was placed into the channel space. The coronal height was measured and marked with a diamond disc to the desired length. The post is cleaned with alcohol, silanated (Ceramic Primer [VOCO]) for 60 seconds, and then air-dried.

Today, the clinician can choose from a variety of post-and-core systems for different endodontic and restorative requirements. These systems and methods are well-documented in the literature.8-10 However, no single system provides the perfect restorative solution for every clinical circumstance, and each situation requires an individual evaluation.

Custom Cast Posts
The traditional custom-cast dowel core provides a better geometric adaptation to excessively flared or elliptical canals, and almost always requires minimum tooth structure removal.1 Custom cast post-and-cores adapt well to canals with extremely tapered canals or those with a noncircular cross section and/or irregular shape, and roots with minimal remaining coronal tooth structure.9 Patterns for custom cast posts can be formed either directly in the mouth or indirectly in the laboratory. Regardless, this method requires 2 appointment visits and a laboratory fee.

 A dual-curing, self-etch adhesive (Futurabond DC [VOCO]) was applied with an applicator (Endo Tim [VOCO]) to the base of the post space and air-dried. Any excess adhesive was absorbed with an endodontic paper point using a rapid
intermittent movement. A dual-cure, resin cement (Bifix QM [VOCO]) was injected into the post channel using an angled tip (Intraoral Tip Type 1 [VOCO]). It is important to remove the tip slowly while injecting, to prevent incorporation of air bubbles.

 The fiber post was immediately inserted into the post hole to the base of the prepared channel and light-cured from different positions for 2 minutes (7a). After polymerization, the fiber post was cut with a diamond bur to the predetermined length. Never use a serrated instrument or shears because this can damage the integrity of the post (7b).
Also, because it is cast in an alloy with a modulus of elasticity that can be as high as 10 times greater than natural dentin,11 this possible incompatibility can create stress concentrations in the less rigid root, resulting in post separation and failure. Additionally, the transmission of occlusal forces through the metal core can focus stresses at specific regions of the root, causing root fracture.11 Furthermore, upon aesthetic consideration, the cast metallic post can result in discoloration and shadowing of the gingiva and the cervical aspect of the tooth.

PREFABRICATED POST-AND-CORE SYSTEMS
An alternative consideration is the prefabricated post-and-core system. Prefabricated post-and-core systems are classified according to their geometry (shape and configuration) and method of retention. The methods of retention are designated as active or passive. Active posts engage the dentinal walls of the preparation upon insertion, whereas passive posts do not engage the dentin, relying instead on cement for retention.1 The basic post shapes and surface configuration are tapered, serrated; tapered, smooth-sided; tapered, threaded; parallel, serrated; parallel, smooth-sided; and parallel, threaded. While active or threaded posts are more retentive than the passive posts, the active posts create high stress during placement and increase the susceptibility of root fracture when occlusal forces are applied. Parallel-sided serrated posts are the most retentive of the passive prefabricated posts, and the tapered smooth-sided posts are the least retentive of all designs.2

Prefabricated Metal Posts
Traditional prefabricated metal posts are made of platinum-gold-palladium, brass, nickel-chromium (stainless steel), pure titanium, titanium alloys, and chromium alloys.2,4 Although stainless steel is stronger, the potential for adverse tissue responses to the nickel has motivated the use of titanium alloy.12 Also, contributing factors to root fracture such as excessive stiffness (modulus of elasticity)13 and post corrosion2 from many of these metal posts have stimulated concerns about their use.

Prefabricated Nonmetallic Posts

The nonmetallic prefabricated posts have been developed as alternatives, including ceramic (white zirconium oxide) and fiber-reinforced resin posts. Zirconium oxide posts have a high flexural strength, are biocompatible, and are corrosion resistant. However, this material is difficult to cut intraorally with a diamond, and to remove from the canal for retreatment.4 The fiber-reinforced composite resin post-and-core system offers several advantages: a one appointment technique, no laboratory fees, no corrosion, negligible root fracture, no designated orifice size, increased retention resulting from surface irregularities, conserved tooth structure, and no negative effect on aesthetics.

THE FERRULE EFFECT

The successful rehabilitation of any endodontically treated tooth using the post-retained system requires the consideration of one specific structural design characteristic: the ferrule effect. The stability of the crown is influenced by the preparation design for endodontically treated teeth. Preserving tooth structure during preparation is paramount in preventing stress concentrations at the cementoenamel junction of the endodontically restored tooth and provides resistance to tooth fracture. The completed crown preparation should have a ferrule design that encapsulates the endodontically re-stored tooth complex. This collar effect provides an antirotational feature for the stability of the crown. Clinical studies have demonstrated and confirmed the importance of this coronal tooth “collar” on the mechanical resistance and retention form of the endodontically restored tooth complex.14 The general guideline is a 1.0 to 2.0 mm preparation on sound tooth structure. Procedures that provide a shoulder on tooth structure, and an axial preparation on the core buildup, will have an insufficient ferrule design. In cases where there is insufficient sound tooth structure for a ferrule design, it is necessary to obtain this dimension through periodontal crown lengthening and/or forced-tooth-eruption procedures.

 

        

[Drsumitra]

Esstech’s results suggest that these materials could significantly improve dental composites, according to Jim Duff, a research chemist at Esstech. Duff presented his research, conducted with assistance from the University of Colorado, during a poster session at the recent American Academy for Dental Research (AADR) annual meeting in Tampa, FL.

"It’ll solve a couple of different problems," Duff told DrBicuspid.com. "The first and foremost is the issue of shrinkage, one of the biggest issues in restoratives. I think these materials will help out in the industry by having the low volumetric shrinkage and the high conversion. Additionally, they will help toughen up the composite so that they tend to flex rather than break or crack."

Leakage of uncured or residual monomer, a potential outcome of low conversion, can be associated with allergic reactions and sensitization, he and his colleagues noted.

“It’ll solve a couple of different problems.”
— Jim Duff, Esstech
Their research found that Exothanes could enhance the strength and limit shrinkage in traditional dental restoratives utilizing methacrylate chemistry, which the industry is already familiar with. The material outperformed the controls displaying higher conversion, lower volumetric shrinkage, and 80% lower shrinkage stress in addition to "superior results in toughness and percent elongation," they reported.

Duff and his team suggest two means of harnessing the potential of the resins: They could be used neat, as a liner material, where their high elongation and toughness will help prevent cracking and caries formation; and they could be used as functional additives to improve the physical properties of existing formulations.

‘Interesting molecules’

The company’s foray into this aspect of restoratives was a result of Duff’s enthusiasm for chemistry.

"The project came out of an unrelated side project I was working on with some interesting molecules that I thought I could make," Duff explained. "So I made them and did some testing on their mechanical properties. At that point, I got my boss’ attention, and we sent them out for shrinkage and conversion testing — and that’s when everybody got really interested in them because they came back with such good numbers."

Esstech combined Duff’s efforts with previous work done on Exothane 10, the company’s first attempt at making a low-shrinkage, high-conversion material.

"We had that one on the shelf in research and development for four years, but we didn’t really know what to do with it, to be honest" Duff said. "The low-refractive index was a challenge for us, because dental materials companies want something that has a higher refractive index for the surface layer of the composite."

The results from testing efforts changed their minds, and the company created other Exothanes, numbered 8, 9, 26, and 32. One other material, Exothane 24, performs differently due to its "higher functionality," according to Duff.

For the AADR study, researchers compared the six Exothane elastomers to a BisGMA:TEGDMA blend (70:30) resin and a urethane dimethacrylate (UDMA) resin. Conversion and reaction kinetics were monitored with the near-infrared reflectance spectrum using Fourier transform infrared spectroscopy. They found that, overall, the Exothanes displayed considerably higher final conversion levels ranging from 94% to 98%.

The researchers also used a linometer to test volumetric shrinkage and found that the BisGMA:TEGDMA blend, UDMA, and Exothane 24 resulted in the greatest volumetric shrinkage and the lowest conversion values. The Exothane 24 possesses higher volumetric shrinkage and lower conversion due to its increased methacrylate functionality, they noted. In addition, "the low conversion does not necessarily indicate poor reactivity," they wrote.

Finally, the researchers used a tensometer to determine polymerization shrinkage stress, noting that "the highly functional Exothane 24 had the highest shrinkage stress" followed by the two control materials. During tensile testing, in which data were obtained by curing the Exothanes and the traditional polymeric matrix resins under a 600-W UVA light, all Exothanes proved to be significantly tougher than the controls, they noted.

"All of these attributes suggest that Exothanes would increase the durability of dental composites," the researchers concluded.

 

        

[drmithila]

A team of German researchers has identified seven quantifiable parameters that can be used for the assessment of dentofacial aesthetics, according to a literature review that looked at how aesthetics can be evaluated in restorative dentistry (Journal of the American Dental Association [JADA], May 2012, Vol. 143:5, pp. 461-466).

Researchers from the Ruprecht Karls University School of Dental Medicine searched the Cochrane Library and Medline from January 1, 1975, to December 31, 2010, and selected 35 studies that focused on assessment strategies for dental professionals.

They were interested in doing this research because they were performing a number of aesthetic corrections on sound anterior teeth in the upper and lower jaw with direct resin composite buildups and wanted to measure the treatment outcome before and after the aesthetic correction, lead study author Cornelia Frese, DMD, told DrBicuspid.com.

"But we could not find a suitable tool for it," she said. "This is why I started to look over the literature, to find some quantifiable parameters."

A more systematic approach

The primary inclusion criteria for the studies in the review were intraoral and extraoral aesthetic assessment methods and indexes or rating scales evaluating aesthetics in restorative dentistry.

The researchers’ goal was to classify the different methods and extract quantifiable clinical parameters that might help in developing an index to be used for diagnosis, treatment planning, and outcome assessment.

“It is no surprise that not all the studies are in agreement.”
— Ronald Goldstein DDS
After reading the qualifying articles, the study authors sorted and grouped the studies into six categories according to their aesthetic assessment topic: golden proportion, soft-tissue measurement, smile and smile line assessment, orofacial indexes and scales, incisor proportion and angulation, and facial aesthetics. These categories included various aesthetic parameters.

Through their review, the authors identified seven parameters that are sufficiently and reasonably quantifiable: the smile line, lip line, incisal offset, location of dental and facial midline, incisor angulations and width-to-height ratios of the maxillary anterior teeth, gingival contour, and root coverage and papilla height.

"These parameters should be considered when providing dental treatment in the anterior area, as they allow for quantification and objective judgment," the study authors noted.

They hope that these findings might increase interest in a comprehensive dental aesthetic index.

"Although aesthetic feelings and sensations are influenced by sex, race, regionalism, and people’s self-perceptions, the seven specified parameters we identified are accepted widely in the West," the authors noted. "If these guidelines are used in careful agreement with the patient’s needs and expectations, both the dentist and the patient may achieve a satisfying aesthetical rehabilitation."

Computer-aided diagnostics

This is an important study because it attempts to summarize the 35 studies dealing with assessment of dentofacial aesthetics, according to Ronald Goldstein, DDS, one of the founders and past president of the American Academy of Esthetic Dentistry and author of Change Your Smile.

"It is no surprise that not all the studies are in agreement," he said. "Nor will they ever be."

However, studies like the ones described in the JADA article can be helpful, along with various tools and techniques employed by the dental profession, in working to achieve an aesthetic result pleasing to the patient, he added.

"One missing ingredient from the studies is the psychological interaction between dentist and patient, especially the demanding and picky patient and the patient who cannot even make a positive final decision about what he or she really wants," he said. "What I see in the future and one of the most certain predictions I make is that computer-aided diagnosis and treatment planning especially for aesthetics will be the norm within a decade."

At least one of the parameters identified by the JADA review has previously been recognized as a valid parameter for aesthetic evaluation.

A systematic literature review conducted by a German team reviewed the evidence on the validity and universal applicability of the smile line (European Journal of Esthetic Dentistry, Autumn 2011, No. 3, pp. 314-327).

"The smile line is a valid tool to assess the aesthetic appearance of a smile," concluded the authors of that study. "It can be applied universally as clinicians and laypersons perceive and judge it similarly."

Other studies also have identified aesthetic guidelines and standards that can be useful to clinicians during cosmetic restorative procedures (JADA, January 2001, Vol. 132:1, pp. 39-45). The authors of that study noted that the overall aesthetic impact of a smile can be divided into four specific areas: gingival aesthetics, facial aesthetics, microaesthetics, and macroaesthetics.

Further research is needed to establish and validate a common dental aesthetic index, according to the authors of this latest JADA review.

"At the moment, we are conducting a pilot study in our department to see if the identified parameters of this review are able to measure changes and differences in facial aesthetics, and if the measurements of aesthetics are objective, reproducible, and consistent," Dr. Frese said. "If we should succeed in our pilot study, these results might be beneficial for dentists in the future."

 

        

[Drsumitra]

 No grinding Crystal Veneers
Crystal Veneers are brand new dental laminates that do not require any tooth reduction with its 0.2mm of ultra thin ceramic veneer.

Post Management after laminate veneers

• Correct brushing and regular scaling are needed to maintain your dental health.
• Avoid biting or chewing solid or hard food.
• Be careful of external shock to avoid damaging attached veneers.
• Regular dental check up is needed.
• Avoid drinking hot and cold drinks for the first 24 hours after treatment.
What are the advantages of laminate veneers?
Laminate veneers, also called as porcelain veneers, could make a huge change on entire smile line. Porcelain laminate veneers are quick, painless, and the result is dramatic. Shape, color, size, and arrangement of teeth can be modified as you’ve always wanted, thus, quick cosmetic dentistry is often used as an alternative for long-term orthodontic treatment.

Does a crystal veneer easily break?
Once a crystal veneer is bonded to a tooth surface, it does not break off easily at all. Due to its ultra thin body, the veneer’s bonding quality with the enamel layer of a tooth is superior to existing veneers.

How long do crystal veneers last?
Crystal veneers can last 7~20 years similar to other dental prostheses although it varies from a patient to a patient depending on how well they manage their prostheses.

What do I do if I don’t like the result of crystal veneers?
Since crystal veneers are done without any teeth reduction, you can simply remove the veneers to revert back to your natural teeth.

        

[Drsumitra]

People would rather have a great smile than be in great shape.

The American Academy of Cosmetic Dentistry conducted a study regarding this issue and found an overwhelming majority opted for the smile.

There were 80 percent of American adults who said they would spend money to fix a flaw due to aging. Among these people, 62 percent said they would choose to improve the quality of their teeth while 48 percent stated that they would devote the money toward weight loss.

About 45 percent of Americans think a smile can successfully battle the effects of aging. The second choice for defying age was a person’s eyes, and 34 percent of the people believed that option. Only 10 percent of the people surveyed thought body shape could defy age, while 6 percent said hair and 5 percent said legs.

The study also showed that 54 percent of Americans older 50 thought that a smile could thwart the effects of aging. Just 38 percent of people ages 18 to 29 believe a smile can have that impact.

“A great smile is always in style, and these results prove it,” AACD President Dr. Ron Goodlin said. “Cosmetic dental professionals can rest assured that their services will be needed.”

The research for the study was done through Kelton Global and was scheduled in September, which is Healthy Aging Month. There were 1,018 adults who were 18 and older that took part in the study.

 

        

[drmithila]

– All-ceramic crown and bridge restorations fabricated with CAD/CAM technology will grow from 40% of overall ceramic unit share to almost 70% in 2015, according to new research by Millennium Research Group (MRG).

Of the materials used to fabricate CAD/CAM restorations, high growth over the next five years in all-ceramic restorations will mainly stem from the segment of newer and alternative materials such as lithium disilicate, MRG said. Lithium disilicate, a glass-based ceramic, is gaining popularity due to its durability by monolithic structure, withstanding greater force than zirconia restorations with similar properties.

Industry experts and key opinion leaders are increasingly discussing the use of lithium disilicate, specifically Ivoclar Vivadent’s IPS e.max, according to MRG.

“The IPS e.max combines lithium disilicate glass-ceramic with zirconium-based bridges, which increases the strength and durability of zirconia while maintaining aesthetics,” said Carmen Chan, an analyst at MRG, in a press release. “Innovations such as these will improve ease of use and in turn, dentists’ productivity, factors that are important to dentists when choosing one type of ceramic over another.”

        

[drmithila]

STUDY CONDUCTED FOR SELF ETCHING ADHESIVES ON INTACT ENAMEL
. Materials and Methods: labial surfaces of 20 caries free permanent upper central and lateral incisors were cleaned, sectioned of their roots. All specimens were mounted on acrylic block and divided randomly into two groups. In one group the application of self-etch adhesive was carried as per manufacturer’s instructions, composite cylinders were built, whereas in the other group, 37% phosphoric acid was applied before the application of self-etching adhesives. Then the resin tags were analyzed using the scanning electron microscope. Results: showed that when phosphoric acid was used, there was significant increase in the depth of penetration of resin tags. Conclusion: the results indicate that out of both treatment groups, pre-etching the intact enamel with 37% phosphoric acid resulted in the formation of longer resin tags and higher depth of penetration of resin tags of the Clearfil SE bond, which might have resulted in attaining higher bond strength of the Clearfil SE bond to intact enamel.

        

[drmithila]

An interesting interview on the internet
Are posts really necessary in endodontically treated teeth?
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In this monthly feature, Dr. Gordon Christensen addresses the most frequently asked questions from Dental Economics® readers. If you would like to submit a question to Dr. Christensen, please send an email to info@pccdental.com.

Gordon J. Christensen, DDS, MSD, PhD
Q
I’m confused about the necessity of using posts in endodontically treated teeth. Some publications and speakers say that posts are always necessary, and others say they are never necessary. When, if ever, should posts be used, and what type of post should be used?
A
During my career to date, I have watched the use of posts and cores for endodontically treated teeth evolve from complicated, expensive, difficult to make, custom cast posts and cores, to metal prefabricated posts made from stainless steel, to titanium or titanium alloy, to today’s popular fiber-reinforced resin-based composite. In my opinion, there have been numerous misunderstandings about the need or lack of need for posts.
In my answer, I will discuss several factors that should be considered before making a decision about whether or not to place posts in endodontically treated teeth. My conclusions about posts are based not only on the research literature, which contains many excellent but sometimes confusing in-vitro studies on extracted teeth, but also my clinical experiences over many years as a practicing prosthodontist.
Factors to be considered in making the decision to use a post
Many have stated that the main reason for placing a post is to strengthen the connection between the coronal build-up material or remaining tooth structure to the root portion of the tooth. In my opinion, that is only partially true. Additionally, the following potentially negative or positive factors should be considered in the decision to use a post. All of these factors should be observed before making the decision:
• Quantity of remaining tooth structure
• Quality of remaining tooth structure
• Remaining adjacent teeth
• Occlusion
• Planned restoration to be placed on the tooth
Quantity of tooth structure remaining
Some teeth have most of the coronal tooth structure remaining after endodontic treatment, and others have very little tooth structure remaining. What is the significance of the amount of remaining tooth structure? For simplicity, I’ll divide the discussion of remaining tooth structure into several categories, and I’ll list them in decreasing order of clinical success:
All of the coronal tooth structure present except the endodontic access hole
If other negative factors (to be discussed later) are not present, such teeth usually do not require posts. After the endodontic procedure is completed, tooth colored resin-based composite should be bonded into the pulp chamber. These teeth usually continue to serve adequately as though they were vital teeth.
At least one-half of the coronal tooth structure remaining
This situation is one of the most common. Assuming the remaining coronal tooth structure does not have any of the negative characteristics discussed next, the occlusion is not heavy, and there are other teeth contiguous with the one being treated, this tooth may not need to have a post. The coronal tooth structure can be built up, usually with retentive resin-based composite build-up material, to provide additional retention for the subsequent restoration, and these teeth have excellent potential to serve uneventfully. However, if other negative factors are present, it is prudent to place a post.
Less than one-half of the coronal tooth structure remaining (Figs. 1-6)
It is my opinion, regardless of the other factors present, that it is still advisable to place a post or posts in such teeth. Endodontically treated teeth with less than one-half of the coronal tooth structure remaining have a reduced chance of long-term service, and patients should be so advised as the treatment plan is developed.
Fig. 1 — Premolar tooth with minimal tooth structure remaining requires a post and pins to ensure connection of the coronal build-up to the remaining root structure.
Fig. 2 — A fiber-reinforced resin-based composite post and two pure titanium pins (Filpins) have been placed in the premolar shown in Fig. 1 to ensure retention of the build-up material.
Fig. 3 — Radiograph from endodontist showing well done endodontic treatment, but minimal tooth structure remaining.
Fig. 4 — Tooth shown in Fig. 3 was built up with two fiber-reinforced resin-based composite posts and bonded composite.
Fig. 5 — Often, endodontically treated teeth with minimal tooth structure remaining, such as the second molar shown, can be built up adequately to provide long-term service.
Fig. 6 — Preoperative view of patient with gross caries in both maxillary and mandibular anterior teeth. Several of the teeth were treated endodontically and posts, build-ups, and tooth-colored crowns were placed on the teeth. Assuming adequate oral hygiene is practiced, teeth restored in such manner will serve for many years.
No tooth structure remaining coronal to the gingival tissue
There are clinical situations in which these teeth should be retained, including if the practitioner plans to extrude the tooth orthodontically. However, when considering the clinical success of dental root-form implants compared to questionable teeth, it is often better to extract the teeth and place implants. In the debatable event that a decision is made to restore such teeth, a post in single-rooted teeth or more than one post in multirooted teeth should be placed. Even with adequately placed posts present, the long-term success of such teeth is very questionable.
No tooth structure coronal to the bone
These teeth should usually be extracted. The only procedure, infrequently accomplished, that may allow teeth with long roots to be retained is orthodontic extrusion of the tooth. However, the cost of orthodontic extrusion and the time involved in waiting for the tooth to extrude and stabilize make the procedure questionable unless there is some major reason to retain the tooth.
Quality of remaining tooth structure
Assuming that there is a significant amount of coronal tooth structure remaining, the quality of the remaining tooth structure should be considered. Often, remaining tooth structure has discolored areas, slightly demineralized areas, cracks, undermined areas, or other negative characteristics. Removal of tooth structure with these characteristics allows a realistic and necessary appraisal of the amount of viable tooth structure remaining. After removing the affected areas, the same suggestions stated in the previous section on quantity of tooth structure remaining apply. Posts are often indicated.
Remaining adjacent teeth
If an endodontically treated tooth stands alone without adjacent teeth present, it will receive significantly more occlusal forces on it when compared to a tooth that has sound adjacent teeth. When restoring a tooth that has no or few surrounding teeth, it is appropriate to use a post or posts to augment the strength of the endodontically treated tooth, and to ensure that the remaining coronal tooth structure is strongly connected to the root portion.
Occlusion
One of the most important factors relative to the question of post placement in an endodontically treated tooth is the nature of the patient’s occlusion. Patients with bruxing or clenching habits place far more stress on teeth than those patients with normal occlusion. Usually, bruxers move their mandibles in left-right and forward-back movements, grinding off canine rise and incisal guidance. Enormous lateral stresses are placed on the teeth of these patients. Clenchers place forces in an apical direction with intense load and frequency. A logical decision is to place posts in bruxing and clenching patients.
Planned restoration to be placed on the tooth
An endodontically treated tooth planned to receive a single crown has minimal stress when compared to a tooth that is planned to be an abutment for a fixed prosthesis or an abutment for a removable partial denture. If an endodontically treated tooth is expected to have significant load placed on it in service, posts should be placed.
Our newest DVD, Posts, Cores and Build-Ups – Predictable and Strong, includes the best materials and techniques for placing adequate posts and cores. This one-hour video includes the best posts, bonding agents, cements for posts, build-up materials, and the most efficient and effective clinical techniques. Item # V1958 Posts, Cores and Build-Ups – Predictable and Strong is available online at http://www.pccdental.com or by calling PCC at 800-223-6569 .
In summary — YES, posts are often needed, and there are many clinical factors related to whether or not they should be used, in addition to just how much tooth structure is remaining. Clinical judgment is still critical in deciding whether or not to use posts.
Gordon Christensen, DDS, MSD, PhD, is a practicing prosthodontist in Provo, Utah. He is the founder and director of Practical Clinical Courses, an international continuing-education organization initiated in 1981 for dental professionals. Dr. Christensen is a cofounder (with his wife, Dr. Rella Christensen) and CEO of CLINICIANS REPORT (formerly Clinical Research Associates).

        

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