a minimal intervention approach to the treatment of a

106 TheJournalofCosmeticDentistry•Winter2006 Volume21•Number4

AbstrAct

The goal of minimally invasive dentistry is ultimately to curtail the resto-ration/re-restoration cycle. When faced with Class IV fractures of the central maxillary incisors, the minimalist approach to treating such cases dictates that the operative decision be based on what would best extend the lifetime of the remaining tooth structure, with as little future intervention as possible. To this end, it is now possible to conservatively place direct composite restorations in the anterior region—for such indications as Class IV fractures—that replicate the form, function, and esthetics of natural teeth. This article presents a case in which a microfilled direct composite resin was used for a Class IV restoration to provide the minimal intervention that would ultimately keep the options open for long-term preservation of the restored tooth.

The rationale behind a minimalist approach is ultimately to curtail the restoration/re-restoration cycle.

IntroductIon

Much attention has been given in recent years to the need for clinicians to embrace minimally invasive and conservative techniques when providing patients with both necessary and elective dental treatments. However, much more than strictly limiting the amount of tooth structure that is removed dur-ing procedures, the concept of a minimalist approach to dentistry beckons us to examine our patients thoroughly, review their conditions comprehen-

A Minimal Intervention Approach to the Treatment of a Class IV Fracture

CliniCal SCienCe Milnar

Dr. Milnar is a graduate of the Univer-sity of Minnesota School of Dentistry. An Accredited member of the AACD, he also serves as an Accreditation examin-er. Dr. Milnar maintains a full-time practice in St. Paul, Minnesota, empha-sizing appearance-related dentistry. He is the past editor of the AACD’s Acade-my Connection, has published numer-ous articles about the direct placement of composites, and is currently a consul-tant for several medical device, bio-med-ical, and dental manufacturers. Dr. Milnar is co-founder of the Minnesota Academy of Cosmetic Dentistry and lec-tures extensively within the Armed Forc-es as well as internationally on the sub-ject of direct composite restorations.

byFrank Milnar, D.D.S.

Volume21•Number4 Winter2006•TheJournalofCosmeticDentistry 107

sively, and consider their treatment alternatives critically. This is not to say—in this author’s opinion—that minimally invasive dentistry cannot be esthetic, durable, and predictably functional. On the contrary, we are fortunate to be practicing in an era when sound science and beautiful esthetics can be applied in a less technique-sensitive manner in order to answer today’s dental challenges in conservative and rewarding ways.

The rationale behind a minimal-ist approach is ultimately to curtail the restoration/re-restoration cycle, to benefit a patient over his or her lifetime.1 The goal is to conserve as much healthy tooth structure as possible through clinical procedures that first assess caries risk, detect the disease before lesion cavitation, re-store caries with maximum reten-tion of sound tooth structure, and seal unaffected areas.1

Visible damage to the maxillary central incisors of an adolescent or young adult patient is a common clinical presentation, and we are often challenged to restore chipped and fractured dentition in this pa-tient group.2,3 A variety of treatment options exist with which to restore such affected dentition. The alterna-

tives include indirect restorations, such as crowns or veneers; or direct-ly placed composite materials, once the health and stability of the den-tition have been ensured. However, as previously noted, the clinician must select the most appropriate treatment alternative that will lead to as little future intervention as possible.4

It is now possible to conservatively place composite restorations in the anterior region—for such

indications as Class IV fractures—that replicate the form, function,

and esthetics of natural teeth.

It has been suggested that young patients, particularly those under the age of 10, receive conservative treat-ments whenever possible.2 When faced with Class IV indications in such patients, placing composite restorations may be the most pru-dent choice, as doing so allows for greater conservation of the remain-ing tooth structure.2,5

However, previous concerns re-garding the use of composites for such indications have focused on how best to achieve the optimal combination of strength and es-

thetics. To answer the profession’s demands, manufacturers have recently introduced direct com-posite materials that demonstrate improved physical properties, du-rability, and strength for long-term function; and polychromatic quali-ties for the placement of restorations that essentially “reproduce” natural tooth structure.5-7 As a result, it is now possible to conservatively place composite restorations in the ante-rior region—for such indications as Class IV fractures—that replicate the form, function, and esthetics of natural teeth.8

Therefore, as a profession, we can rise to the challenge of addressing both immediate and long-term oral care objectives when treating an-terior Class IV fractures. First, plac-ing direct composites has an impact only on the tooth structure that is af-fected, something especially impor-tant if the dentition have not been previously treated. Second, it recog-nizes that the anticipated desire for conservative treatment in the future requires a conservative therapy now. Minimal intervention applied to the operative field keeps the options open for long-term preservation of the restored tooth.9


Figure 1: Preoperative 1:1 view of the patient’s fractured left maxillary central incisor.


cAse PresentAtIon

A 15-year-old male presented with a fractured left central maxil-lary incisor, tooth #9 (Fig 1). Nei-ther the patient nor his parents were interested in irreversible, indirect treatment options and were instead inclined to pursue immediate, more conservative restorative alternatives. They therefore elected to have the fractured central incisor restored with direct composite. To thorough-ly assess the patient’s condition, a complete intraoral examination was performed and an oral history tak-en, including radiographs and pho-tographs. The patient was in good health, and no pathologies were found that would contraindicate restoration of the affected tooth.

treAtment PlAnnIng

To fully evaluate the case, a visual assessment was performed and the patient’s occlusion was analyzed. Additionally, the morphologic, his-tologic, and optical characteristics of the adjacent teeth were noted.

From a material selection stand-point, when using direct composites

to reproduce natural tooth structure, the clinician has traditionally re-quired one of two things: either a va-riety of composite shades in order to duplicate what is observed in natural teeth—particularly in complex Class IV fracture cases; or a single com-posite material that demonstrates a chameleon effect and esthetic in-visibility. To simplify the restorative process in this case, yet still provide the patient with nature-replicating esthetics and functional predictabil-ity, a microfilled composite (Gradia Direct, GC America; Alsip, IL) that mimics the reflectivity observed in natural teeth was selected.8,10

To determine the appropri-ate composite shades, a shade guide based on the Vitapan Classi-cal shades (Vident; Brea, CA) was used, and it was determined that the ideal dentin composite shade would be A2 (Fig 2). The selected dentin shade and the enamel com-posites were previewed on teeth #8 and #9 (Fig 3), and the shades identified visually were verified us-ing a digital spectrophotometer (EasyShade, Vident).

dIAgnostIc WAx-uP

An impression was taken prior to preparing the tooth in order to create a diagnostic wax-up; an esthetically enhanced wax-up demonstrating the appropriate length of the restored tooth #9; and, ultimately, a high-vis-cosity putty stent (Exafast Putty, GC America) (Fig 4).11,12 The putty stent, once placed in the patient’s mouth, would be used for spatial reference as a volumetric, three-dimensional guide for placement of the compos-ite restorations; and to preserve the facial/lingual line angle (Fig 5).11,12

PrePArAtIon Protocol

Tooth #9 was prepared with dia-mond burs to create a .5-mm modi-fied lingual shoulder, in addition to a 2-mm facial bevel. An infinite/virtual bevel was also placed that would facilitate transitioning of the enamel shade of composite into the remaining tooth structure.12,13 This long bevel was approximately 0.3 mm in depth, extending 2 mm to 3 mm around the entire margin. This preparation would support the frac-ture resistance and durability of the


Figure 2: It was determined that the patient’s dentin composite shade should be A2.

Figure 3: To preview the selected shades, composites were placed on teeth #8 and #9, including the dentin,

enamel, and translucent shades.


restoration by enabling the place-ment of a layer of composite at the restorative margins.8,13

comPosIte lAyerIng technIque

Following preparation, tooth #9 was pumiced, rinsed, and dried, then etched for 20 seconds with a self-etching adhesive bonding system (UniFil® Bond, GC America). The self-etching primer (UniFil® Bond Self-Etching Primer) was gently air-dried for 5 seconds. The bonding agent was then applied to the prepa-rations (Fig 6) and light-cured for 10 seconds with a light-emitting diode (LED) curing light (UltraLume LED

5, Ultradent; South Jordan, UT). This light was used throughout the restorative process.

After positioning the putty stent in the patient’s mouth, build-up of the restoration began with the placement of a 1.5-mm thick layer of the selected A02 dentin shaded composite on tooth #9 to form the lingual enamel layer (Fig 7). This shade was selected to control the restoration’s opacity and eliminate any show-through. The composite was carefully sculpted into place, after which it was light-cured for 20 seconds. It is important to note that throughout the composite place-

ment process, use of the stent, as well as controlled use of composite placement instrumentation, helped ensure accurate and precise compos-ite placement that would ultimately facilitate a simplified finishing and polishing protocol.14

To preview the lingual enamel layer and assess opacity, the putty stent was removed. It was returned to the patient’s mouth for the place-ment of the bulk of the artificial dentin layer. The standard anterior shade A2 of the selected composite was placed in a 2-mm thick incre-ment to form the body and mam-elons of the restoration on tooth


Figure 6: A self-etching adhesive bonding agent was placed onto the preparation of tooth #9.

Figure 4: A putty stent was created from the diagnostic wax-up.

Figure 5: View of the putty stent in place in the patient’s mouth.


#9 (Fig 8). Prior to light-curing for 20 seconds, this layer was carefully sculpted into place just shy of the proximal and incisal edges, as well as onto the long bevel to mask the fracture line,8 in order to leave room for the final enamel layer.

To create natural-looking varia-tions in shade and chroma, a high-value halo was created by placing Xtra bleach white (XBW) shade composite along the incisal third of tooth #9, sculpting it into place,

and light-curing it for 20 seconds after removal of the putty stent (Fig 9). Greater translucency was created with the placement of a thin transi-tional layer of anterior gray translu-cency (GT) composite along the in-cisal edge, after which the tooth was cured for 20 seconds (Fig 10).

A thin final enamel layer of bleach white (BW) composite was placed on tooth #9 with the putty stent removed (Fig 11), then sculpt-ed and light-cured for 20 seconds.

Before imparting surface texture and tertiary characterizations, the enamel layer and overall restoration was assessed with the putty stent in place (Fig 12). To ensure a com-plete depth of cure, transenamel light-curing was performed from multiple aspects.

FInIshIng And PolIshIng

During the finishing stages, when contouring and/or gross reduction of the composite resin restorations is performed, this author has found


Figure 10: Incisal translucency was created by placing GT shaded composite along the incisal edge.

Figure 9: The Xtra bleach white (XBW) shade of composite was placed along the incisal third to create

a high-value halo effect.

Figure 8: Dentin shade A2 composite was placed to form the dentin replacement layer and mamelons.

Figure 7: Shade A02 of the dentin composite was placed to form the initial lingual enamel layer and

control show-through.


Figure 11: A final enamel layer in BW was placed over the restoration on tooth #9.

Figure 13: Postoperative view of the patient’s natural smile.

Figure 14: Postoperative 1:1 view of the completed restoration on tooth #9. Note the symmetry with

tooth #8.

it beneficial to use a variety of burs and diamonds.14 In this case, to cre-ate the final form of the incisal edges and finish the embrasure between teeth #8 and #9, an ultra-fine pol-ishing disc (3M ESPE; St. Paul, MN) was used. To refine the restoration’s surface, a green stone (Brasseler; Savannah, GA) was used, while mi-cromorphology was created using a Brasseler carbide bur. To achieve a lifelike final luster, Brasseler polish-ing points and brushes were used, in addition to a chamois wheel. Upon

completion, the final restoration on tooth #9 blended invisibly with tooth #8 (Figs 13 & 14).

conclusIon

When considering the manner in which to apply a minimal interven-tion approach to the restoration of a Class IV fracture in the anterior, it is perhaps prudent to remember that our first objective in treatment is to do no further harm. When we combine technical skill with the use

of scientifically advanced composite materials that enable us to repro-duce a tooth, we are now able to re-store form and function in a beauti-fully conservative manner. When we implement conservative techniques, we are in fact allowing for the pos-sibility of further esthetic options in the future, which is particularly im-portant for young patients.

However, when employing mini-mally invasive composite layering techniques, it is incumbent upon clinicians to combine technical


Figure 12: The entire restoration was evaluated with the putty stent in place.


skill with a heightened sense of ob-servation so that the natural tooth structure can be meticulously repro-duced. While products such as cha-meleon-like composites facilitate the easier creation of lifelike and esthetic direct restorations, it is still the responsibility of the clinician to analyze the characteristics and nuances of the individual tooth or teeth and to select the appropriately shaded material for placement.

dIsclosure

The author has received financial and materials/product support from GC America.

References1. White JM, Eakle WS. Rationale and treat-

ment approach in minimally invasive den-tistry. JADA 131(Suppl. 13S-19S), 2002.

2. Saghezchi KS. Treatment of a broken cen-tral incisor in children after trauma. The Journal of Cosmetic Dentistry 19(1):108-112, 2003.

3. Featherstone RW. Accreditation clinical case report, Case Type IV: Class IV direct resin restoration (tooth #8). The Journal of Cosmetic Dentistry 19(2):44-48, 2003.

4. Peters MC, McLean ME. Minimally invasive operative care. I. Minimal in-tervention and concepts for minimally invasive cavity preparations. J Adhes Dent 3(1):7-16, 2001.

5. Terry DA. Direct composite resin restora-tion of adolescent Class IV tooth fracture: A case report. Pract Perio Aesthet Dent 12(1):23-29, 2000.

6. Fahl N Jr. Achieving ultimate anterior es-thetics with a new microhybrid composite. Compend Contin Educ Dent 26(Suppl.)4-13, 2000.

7. Terry DA, Geller W, Tric O, Anderson MJ, Tourville M, Kabashigawa A. Anatomi-cal form defines color: Function, form, and aesthetics. Pract Proced Aesthet Dent 14(1):59-67, 2002.

8. Milnar FJ. Immediate, direct rehabilitation of fractured maxillary central incisors in the pediatric patient. Dent Today 23(4):98-103, 2004.

9. Peters MC, McLean ME. Minimally invasive operative care. II. Contemporary techniques and materials: An overview. J Adhes Dent 3(1):17-31, 2001.

10. McDonald JM. Restoring function and es-thetics with a new micro-hybrid compos-ite. Contemp Esthet Restor Pract 7(9):22-32, 2003.

11. Garcia LT, Bohnenkamp DM. The use of diagnostic wax-ups in treatment planning. Compend Contin Educ Dent 24(3):210-216, 2003.

12. Behle C. Placement of direct composite veneers utilizing a silicone buildup guide and intraoral mock-up. Pract Perio Aesthet Dent 12(3):259-266, 2000.

13. Bichacho N. Direct composite resin res-toration of the single anterior tooth: clinical implications and practical appli-cations. Compend Contin Educ Dent 1996; 17(8):796-802.

14. Peyton JH. Finishing and polishing tech-niques: Direct composite resin restora-tions. Pract Proced Aesthet Dent 16(4):293-298, 2004.

______________________v


Figure 9 on page 114 of the Fall 2005 issue of the Journal (vol. 21 no. 3) shows the finals, rather than the provisionals, for the case. The correct photograph of the provisionals is shown here. The AACD regrets the error.

correctIon

a minimal intervention approach to the treatment of a

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