Marginal Adaptation of Stainless Steel Crowns

Meghan Sullivan Walsh November 28, 2010

Literature Review - St. Joseph/LMC Pediatric Dentistry

Marginal Adaptation of Stainless Steel Crowns

Resident: Meghan Sullivan Walsh

Program: Lutheran Medical Center- Providence

Article Title: Marginal Adaptation of Stainless Steel Crowns

Authors: Theodore P. Croll, DDS; David W. Epstein, DDS, MSD; Cosmo R. Castaldo, DDS, MSD

Journal: Pediatric Dentistry

Volume (number), Year, Page #’s; 25:3, 2003, pages 249-252

Major Topic: The procedure of adapting, finishing, and polishing crown margins.

Overview of Method of Research: Report gives details of methods used to adapt SSC margins as precisely as possible to prepared teeth.

Findings:

Technique for SSC procedure:

Tooth preparation for the SSC Includes debridement of carious tooth structure and placement of liner on dentin as indicated. Tooth preparation is designed such that the form of the tooth can be replicated by that of the SSC. After proper size crown form is selected, marginal adaptation of the crown is as follows:

1)Using a abrasive wheel, crown length is custom cut. The abrasive wheel is recommended by the authors rather than scissors for a more precise reduction. The wheel is used to recreate marginal ridge height in relationship to the adjacent teeth and have sufficient extension to overlap the cervical bulge. On primary teeth the margins can be at or slightly above the CEJ. In an adult molar the crown margin of a SSC should be coronal to the CEJ so as not to compromise the fit of a precision cast crown. During crown size selection, if the selected crown does not fit the prepared tooth, either the tooth is insufficiently prepared, the crown is too small or both.

2) Using a crimping plier the edge of the crown form is bent slightly inward around the crown periphery.

3) The abrasive wheel is used along the edges toward the margins from the occlusal direction (counterclockwise.) This will both thin the margins and curve it slightly towards the axial walls of the tooth.

4)The surfaces of the crown are then smoothed and polished with a rubber wheel in the same direction.

5) A polishing cloth or chamois wheel using Tripoli polishing agent and rouge can then be used for final finishing.

Key Points: Summary: The authors state that the methods described are used for both primary and permanent molar SSC forms and are expected to remain in place for 5-15 years. The clinician should strive to replicate the natural state when repairing a tooth. The goal is to restore it’s form, function and purpose in a biologically acceptable manner.

Assessment of the Article: While I understand the value of preparing an SSC in the manner with which is described above, I don’t think it has many practical uses in a pediatric office. The amount of time used to both trim and polish an SSC as mentioned may be difficult to obtain while placing a SSC on a wiggly 5 year old in the dental chair or in a OR setting. Pre formed SSC do have good adaptation and can serve the purpose of a 5 year restoration in a pediatric patient.

Effects of Cavity Preparation and Lamination on Bond Strength and Fracture of tooth colored restorations.

Resident: Swan
Article Title: The Effects of Cavity Preparation and Lamination on Bond Strength and Fracture of Tooth-Colored Restorations in Primary Molars
Author: Suwatviroj, et al.
Journal: Pediatric Dentistry 25:6, 2003
Main Purpose of Article: Examine Bond Strength (ultimate load at failure) and Fracture modes between different preparation types and different layering of restorative materials
Methods: 80 extracted primary second molars carious on one surface only were mounted and randomly divided to be prepped with box-only or dovetail preparation according to standardized measurements. Teeth were divided into 4 subgroups for each restorative procedure. T-band was adapted and teeth were restored in one of 4 ways:
1: Packable Composite 2: RMGIC 3: RMGIC/PC (open sandwich) 4: RMGIC/PC with experimental bonding agent (K-14). Restorations were tested for ultimate load at fracture using a unversal mechanical testing machine placing force directly on the marginal ridge of each restoration. Surfaces of teeth and restoration were examined microscopically and classified as adhesive, cohesive, or mixed fractures.
Statistical Analysis: ULF were recorded and means and SD's were compared using ANOVA.
Results: There was no effect of type of restorative procedure on ULF, nor any effect of cavity preparation type on ULF. The predominant fracture mode for both types of preparations was "mixed." The distribution of fracture modes in the two preparation types differed significantly, with no adhesive fractures occurring in any restorations in dovetail preparations. The other comparisons of fracture modes between materials did not differ significantly. Adhesive fractures were limited to box-only preps restored with RMGIC. RMGIC restorateions in box-only preps sustained a lower load than PC restorations before fracturing.
Conclusions: Conservative restorations are just as durable as dovetail restorations. Probably a good idea to use dovetail if electing to use just RMGIC.

Use of self-etching adhesive system and compomer for splinting traumatized

Resident’s Name: Jessica Wilson

Article title: Use of self-etching adhesive system and compomer for splinting traumatized
incisors

Author(s): Croll & Helpin.

Journal: Pediatric Dentistry

Year. Volume (number). Page #’s: 2002. 24:1. 53-56.

Major topic: Splinting traumatized incisors

Overview of method of research: Case Report

Case History:
13 year-old male fell and hit his maxillary incisors on the floor. Proper initial precautions were taken and upon clinical examination and transillumination the lateral incisors were classified with a subluxation injury and were both slightly mobile. The central incisors both presented with MFLI Ellis Class II fractures. These centrals also displayed moderate mobility, sulcular bleeding, mild palpation sensitivity and were diagnosed with “extrusive luxation”.

Treatment:
1. Prophy brush to clean labial surfaces of incisors.
2. Dead-soft ligature wire was twisted upon itself to make a double strand and left incisors were treated with L-Pop for 20 sec., air thinned and cured for 10 sec.
3. The splint wire was placed passively across the left lateral incisor at the gingival 1/3 in order to allow continued use of ortho retainer. A small amount of compomer (Hytac) was placed on each tooth and pressed into place with a hand instrument and light cured for 40 seconds. The same was repeated for the central.
4. Same steps were taken for the right incisors and proper occlusion was verified.
5. Exposed dentin was covered with a thin layer of vitrebond and peripheral enamel was reduced slightly with a diamond bur.
6. Self-etching adhesive was added to liner and enamel for 30 seconds.
7. Composite “bandage” was placed with the use of a matrix band and wedge.
8. The child was prescribed amoxicillin to help in periodontal and pulpal healing.
9. PA radiograph was taken and revealed NSF.
10. Re-evaluation in 8 days revealed unremarkable findings other than slight mobility of the central incisors. Patient reports wearing his ortho retainer daily.
11. The splint was removed with a slow speed diamond bur and all incisors were asymptomatic with unremarkable findings.

Discussion:
Compomer materials are polyacid-modified, resin-based composites. Although they contain glass filler particles, they are appropriate for interim restorations, with sufficient strength and durability for a passive splint yet are cut away easily once they have served their purpose.

Key points/Summary:
Using a self-etching adhesive bonding system and compomer material facilitates both the resin bonding and its removal.

Assessment of Article:
Nothing “earth shattering”, but interesting enough.

SEM and Microleakage Evaluation of 3 Flowable Composites as Sealants Without Using Bonding Agents

Resident: Cho

Author(s): Kwon et al.

Journal: Pediatric Dentistry

Year. Volume (number). Page #’s: 2005. 27. 48-53.

Major topic: flowable composite, sealant

Minor topic: microleakage, SEM

Type of Article: Scientific Article

Main Purpose: The aim of this study was to determine if 3 different flowable composites could be used as pit and fissure sealants without the use of bonding agents.

Overview of method of research:

The sealant material used in this study: Ultraseal XT Plus

The flowable composites used in this study: Filtek Flow, Tetric Flow, Charmfil Flow

SEM observations

Two extracted, erupted human permanent third molars were selected for each sealant material. The flattest surface was ground flat and polished. The tooth’s crown was sectioned in half mesiodistally through the flat ground surface. Each enamel surface was cleaned with pumice/water slurry, then rinsed, and dried. 35% phosphoric acid conditioning gel was applied to each surface for 30 seconds, then rinsed, and dried. A sealant material was applied to 1 of the 2 acid-etched surfaces for 20 seconds, then light cured for 40 seconds. The tooth section with the sealant applied was dissolved in 1 N HCl and the sealant was detached. For each SEM specimen, both the section of the etched enamel surface and the detached sealant from the other section were mounted together and examined.

Microleakage assessment

Fifty-four extracted human premolars previously stored were randomly divided into 3 groups:

Group 1 – Ultraseal XT Plus/Filtek Flow

Group 2 - Ultraseal XT Plus/Tetric Flow

Group 3 - Ultraseal XT Plus/Charmfil Flow

¼ round bur in high-speed handpiece was used to do enameloplasty of 1mm thickness. All of the teeth were prepared by the same operator. Pumice slurry was used to clean the tooth. The occlusal fissures were acid etched for 30 seconds using 35% phosphoric acid, rinsed, and dried. Flowable composite was applied to half of the prepared fissure using a dental explorer. Penetration time was 20 seconds, then the composite was light cured for 40 seconds. The filled sealant was then applied to the other half of the fissure using the same method and light cured for 40 seconds. The teeth were treated with 1% methylene blue dye. One person, who was blinded to the treatment groups, recorded the extent of dye penetration using the following scale:

0 – no dye penetration

1 – dye penetration restricted to the outer half of the sealant

2 – dye penetration to the inner half of the sealant

3 – dye penetration into the underlying fissure

Findings: The Ultraseal XT Plus showed significantly less microleakage than the 3 flowable composites. There was no statistical different in microleakage among the 3 flowable composites. No void was observed in any of the Ultraseal XT Plus groups. However, a void was found in 3 of the Filtek Flow specimens and 6 of the Tetric Flow and Charmfil Flow specimens.

Key points/Summary: Filled sealant is more effective in sealing mechanically prepared occlusal fissures compared to flowable composites. Special care is needed when applying flowable composites to occlusal fissures because of void formation.

Assessment of Article: Good article. Would be interesting to know how adding the bonding agent to the flowable composite groups would have affected the results of this study.

Multi-colored Dual-cured Compomer

Meghan Sullivan Walsh November 17, 2010

Literature Review - LMC/ Providence Pediatric Dentistry

Multi-colored Dual-cured Compomer

Resident: Meghan Sullivan Walsh

Program: Lutheran Medical Center - Providence

Article Title: Multi-colored Dual-cured Compomer

Authors: Theodore P. Croll, DDS; Mark L. Helpin, DMD; Kevin J. Donly, DDS, MS

Journal: Pediatric Dentistry

Volume Number, Year, Pages ; Volume 26/Number 3, 2004, Pages 273-341

Major Topic: MagicFil

Overview of Method od Research: Introduction and usage of new compomer called MagicFil.

Click on this Adam for the photos in color please:

http://www.aapd.org/upload/articles/Croll-26-03.pdf

Findings: MagicFil is a new poly acid-modified resin-based composite (compomer.) The material polymerizes both by visible light activation and chemical resin curing. While other compomers undergo resin polymerization only by light exposure, the 2-component colored compomer is blended while being injected through the tip also activating chemical polymerization. The other unique side to this compomer is that the material is manufactured in four bright colors with “glitter” inclusions. The colors are blue, purple, yellow and universal. This material is specifically designed for restorations on primary teeth. The physical properties are that of any poly acid-modified resin-based composite and can be used in the same fashion ie: Class I, Class II and Class V restorations. The application of this material is also the same as any other compomer. The author recommends treating teeth that are expected to exfoliate within 3-5 years. They also state that the children ages 7-11 are the biggest enthusiasts for this new material.

Method: A single case and it’s preparation was discussed 1) Same cavity preparation as a composite, no need to include sharp angels or grooves. 2) GI base was used due to deep preparation 3) place matrix band and wedge 4) rough enamel surfaces with high speed diamond bur 5) L-pop or any self etching material can be used along with a bonding agent 6) small increment of material (PURPLE shade) 1-1.5 mm thick injected into preparation and light cured for 30 seconds 7) second layer applied and cured for 40 seconds 8) trim excess composite with high speed 9) etch a second time, rinse, add sealant to grooves and cure 10) check occlusion

Key Points: Great material for pediatric practice. Physical properties of material are that of any poly acid modified resin-based composite.

Assessment of the Article: Since one of the authors was head of our Pedo department at Temple I had already heard of the material. It seems like it would have use in a Pedo practice and would offer our pediatric patients another choice in their dental treatment. Also, who doesn’t like Glitter ....right Jessi?

11/17/2010 Comparing Bond Strengths of Brackets on Primary Teeth With 3 Different Primers

Resident: Hencler
Date: 11/17/2010

Article title: Comparing Bond Strengths of Brackets on Primary Teeth With 3 Different Primers

Author(s): Ozoe-Ishida, Endo, Shimooka
Journal: Pediatric Dentistry V32/NO2 MAR/APR 10
Major topic: Bonding strengths
Type of Article: Scientific

Main Purpose:
Examine the bond strengths and the mode of bracket failure in brackets bonded to primary tooth enamel using conventional primers, self-etching primers, and moisture-insensitive primers.

Overview of method of research:
78 primary teeth (30 canines, 24 first molars, 24 second molars) were collected and divided equally into 6 groups of 13 teeth. In group 1 the enamel surface was etched and a coat of conventional primer was applied to the enamel surface. In group 2 a coat of self-etching primer was applied to the enamel surface. In group 3 the enamel surface was etched and a coat of moisture-insensitive primer was applied. The adhesive systems used in groups 4, 5, and 6 were the same as those used in groups 1, 2, and 3, respectively, but before priming, each tooth in groups 4, 5, and 6 was moistened with a thin coat of water. Transbond XT was used to attach each bracket. A universal testing machine was used to test the bond strengths for each group in Newtons. The bond strengths were checked against 6MPa, which is considered to be the minimum clinically acceptable bond strength.

Findings: See tables

Key points in the article discussion:
Among the factors that govern bond strengths are types of adhesives, types of ortho brackets, type of teeth, and moisture contamination. This study found a notable drop in bond strength of the conventional adhesive system in a moisture-contaminated environment and a high incidence of bond failure at the enamel-adhesive interface. The moisture insensitive primer adhesive system is hydrophilic. The self-etching primer adhesive system can be used in either dry or wet fields. By contrast, the conventional adhesive system is hydrophobic. Failure is likely due to insufficient formation of resin tags as a result of the decreased permeation of the bonding agent into primary tooth enamel under conditions of moisture contamination. All bond strengths found in this study were less than 6 MPa. The low levels of shear bond strength in primary teeth vs. permanent teeth could be attributed to differences in the surface structure of enamel or the thickness of adhesives placed b/t the bracket base and enamel surface. The enamel surface of primary teeth is predominantly prismless vs. permanent teeth. Furthermore, the ratios of moisture and organic contents of primary teeth enamel are higher and the ratio of inorganic contents was lower than those of permanent teeth. These characteristics of primary tooth enamel account for poorly developed etching patterns and cause lower bond strength.

Summary of conclusions:
1) The conventional primer adhesive system does not offer adequate bond strength of brackets bonded to primary tooth enamel under wet conditions. 2) The self-etching primer adhesive system and moisture insensitive primer adhesive system have clinically acceptable bond strengths of brackets bonded to primary tooth enamel in either dry or wet conditions. 3) These adhesive systems under specific conditions enable practitioners to use a primary tooth in the sectional bracket appliance as an anchor tooth, thus helping improve the outcome of early treatment for malocclusion.

Assessment of article:
Okay article, a little boring and nothing groundbreaking. When bonding brackets using any adhesive system, attention to detail and moisture control are very important and will ensure less frequent bracket failure on primary or permanent teeth.

Anterior Fiber-reinforced Composite Resin Bridge: A Case Report

Resident’s Name: Jessica Wilson

Program: Lutheran Medical Center - Providence

Article title: Anterior Fiber-reinforced Composite Resin Bridge: A Case Report

Author(s): Chafaie & Portier.

Journal: Pediatric Dentistry

Year. Volume (number). Page #’s: 2004. 26:6. 530-534.

Major topic: Treatment of missing incisors

Overview of method of research: Case Report

Purpose:
To present a clinical case of a single tooth replacement by means of a polyethylene FRC bridge.

Background:
Implants are generally not intended before the end of the growth period around 18 years of age and are expensive.
RPD are often used in very young children when adjacent teeth are not in final correct position, but are often not esthetic.
A plastic tooth can be bonded to orthodontic appliances when a child is missing an anterior tooth and in ortho treatment.
A PFM bridge is the most invasive treatment option and can lead to unaesthetic results as can a traditional Maryland bridge with a metal framework.

Methods:
16 year old male referred from orthodontist to Pediatric Dept. in Marseille University in France 1 month after ortho treatment completion. The patient lost #8 due to trauma at 12 years old and had been using a removable appliance with a plastic tooth which had been repaired on several occasions since then. The patient asked for a more esthetic and comfortable treatment.
The patient presented with minimal overbite so no tooth reduction was necessary. A short-span alginate impression was taken in order to reduce tension and provide a more accurate result. Polyvinylsiloxane die material was used to pour the impression up. Length measurement was done by flattening dead soft foil from the middle thirds of each abutment crossing the pontic area directly under the incisal edge. Polyethylene plasma-treated fiber system (Ribbond) was used for the bridge framework. The operator made sure to avoid handling the Ribbond with fingers until it was wetted with bonding agent.

Findings:
Indirect technique provides a better adaption, better polymerization and smoothness compared to the direct technique where excess composite tends to collect in the embrasures.
By using fast-setting silicone die material, the procedure can be done easily chair side and the elasticity of the model allows easy removal of the FRC bridge.
Compared to the traditional metal framework, the FRC bridge is more esthetic with no dark shadow and easier to bond.

Key points/Summary:
FRC bridge is a new hygienic and non-irritating treatment option that generally requires no tooth preparation and can be considered permanent or a long-lasting provisional.

Assessment of Article:
I had never heard of this technique before and found it very pertinent and interesting. Would have liked to see some follow-up, but I’d love to try it!

Strip Crown Tips

Resident: Swan
Article Title: Bonded Resin composite Strip Crowns for Primary Incisors: Clinical Tips for a Successful outcome
Author: Kupietzky, Ari
Journal: Pediatric Dentistry 24:2 (2002)
Main Purpose: Present some simple clinical tips to assist the clinician in an esthetic and superior outcome

Tips:
1. obtain ideal oral hygiene prior to commencement of treatment; inflamed gingiva may result in bleeding during curing and affect the bond/discolor the restoration.
2. pierce the strip crown with a sharp explorer at mesial or distal incisal angle to create a vent for the escape of air bubbles.
3. Use the slit-dam method: punch two large holes 1 cm apart and connect them with scissors-remove RD during crown placement
4. fill and cure each crown individually with unfilled crown forms in place to ensure proper spacing between restorations.
5. Remove any excess collar of cured bonding agent, which will interfere with proper seating of the crown form.
6. Minimally fill the crown form
7. Use a cleoid/discoid carver to remove the crown form
8. In cases of black-colored arrested caries, a masking agent may be used.

Assessment: Good tips. Strip crowns are good.

Parental Satisfaction With Bonded Resin Composite Strip Crowns for Primary Incisors

Department of Pediatric Dentistry
Resident’s Name:Murphy Program:Lutheran Medical Center - Providence
Article title: Parental Satisfaction With Bonded Resin Composite Strip Crowns for Primary Incisors
Author(s): Ari Kupietsky, DMD MSc William Waggoner, DDS, MS
Journal: Pediatric Dentistry
Year. Volume (number). Page #’s: 2004. vol 26 No 4. 337-341
Major topic: Parental Satisfaction for strip crowns
Main Purpose:
The purpose of this study was to evaluate the parental satisfaction of bonded resin composite strip crowns (SC) for the treatment of maxillary incisors, and to compare their satisfaction with the clinical evaluation and success of the crowns.

Overview of method of research:
This was a retrospective clinical study of pt’s whom had SC placed, returned for 1 recall visit, and whose parents gave consent and agreed to answer a few questions. 112 restorations in 40 children were reviewed. Color photographs were evaluated by 2 independent pediatric dentists. The dental assistant asked the parents a series of questions and recorded their answers

Findings:
Overall parental satisfaction was excellent. There was no significant difference found between the dentists and parents in terms of color, size, and overall appearance. Satisfaction with regard to color had the worst rating, and satisfaction with regard to durability had the highest rating. It should be noted that teeth that were treated with pulpectomies and had an iodoform paste placed had the worst color match.

Key points/Summary:
Color match is least important to parents, durability is most important.

Assessment of Article:
“It is what it is”-Bill Belichick

Posterior resin-based composite: review of literature

Resident: Cho

Author(s): Burgess et al.

Journal: Pediatric Dentistry

Year. Volume (number). Page #’s: 2002. 24. 465-479.

Major topic: resin-based composite restoration

Type of Article: Literature Review

Main Purpose: To review current posterior resin-based composite products

Findings:

Compomers or polyacid modified composite resins:

A compomer is a polyacid-modified, resin-based composite with constituents derived from composite and glass ionomer. They contain etchable glass fillers that release fluoride. Less wear resistance and mechanical than composite resin, but the fluoride release and uptake are greater and it is easy to use.

Resin-based composite composition and improvement:

Resin-based composite consists mainly of a resin matrix and inorganic filler particles. The resin matrix is made up of resin monomers and initiator/catalyst system for polymerization. Most common monomers are bis-GMA and urethane dimethacrylate (UDMA). The filler particles are silicon dioxide based. Macrofilled developed in 1960s range from 10-100um. Microfilled developed in 1970s average less than 0.1um and have extremely smooth surface but lower fracture toughness and mechanical properties. Midsize-filled particles range from 1.0-10um. Minifilled particles range from 0.1um-10um, which have high strength and better polish than midsize-filled. In the 1980s, hybrids containing midsize-filled or minifilled and microfilled particles were made to be used in posterior bearing surfaced.

In the past, resin based composites (RBC) required mixing and were chemically activated. Now, resin-based composites are visible-light cured, single-paste, no mixing required, have fewer voids, greater strength, better color stability, and higher surface polymerization rates than chemically activated RBC. With present-day RBC, polymerization shrinkage ranges from 2%-3%. Shrinkage of the composite resin transfers stress to the walls of the cavity and can tear the adhesive bond to the tooth or pull opposing cusps together by deforming the tooth. Shrinkage of the RBC can subsequently cause post-op sensitivity, increased microleakage, staining, and recurrent caries.

The current American Dental Association Council of Scientific Affairs recommends that posterior resin-based composites should be radiopaque.

Flowable resin-based composite:

Flowable RBC’s have 37%-53% less filler volume compared to conventional minifilled hybrids. In a study conducted comparing flowables with minifilled hybrids, flowables had inferior mechanical properties. Flowables are recommended only in low-stress areas or very conservative occlusal restorations. Flowable RBCs are recommended as a liner of proximal box for class II restorations in order to adapt to surface irregularities. However, no clinical trials have been yet to be reported on the superiority of this technique compared to using only a RBC.

Packable resin-based composite:

“Packable” or “condensable” RBCs were introduced with the expectation that they would handle or condense like amalgam. These RBCs had high filler loading. Leinfelder and others have reported that overall, the mechanical properties of packable composites are not substantially better than most conventional minifilled hybrids. Packable composites do not polish as well as conventional RBC.

Clinical trials:

The results of clinical trials using resin composite as a direct restorative material for posterior restorations have shown increasing success with newer more highly filled products.

Key points/Summary: Composites and their accompanying adhesives are unforgiving compared to amalgam. With low- to moderate-caries-risk patients, resin-based composite should be the initial material used to restore a small carious lesion in the posterior region. Flowable or hybrid RBC would be ideal in this situation. Hybrid or packable RBC is indicated for small to large posterior restorations. Compomers should be limited to Class III or V restorations in the permanent dentition.

Assessment of Article: Great article! Very good overview how composite properties have changed over time and acknowledges that more research needs to be conducted using current composite materials. At the end of the article noted that oftentimes clinical trials are inaccurate due to incorrect sample size, no power analysis, and materials and methods were not listed.