Clinical Corner: Information on Dental Procedures

Articles

What's Hot: Dr. Glazer on Jazz
Combating Hidden Decay with Early Detection
Atraumatic Removal of Defective Crowns
Balancing: The Art, Science and Business of Dentistry
Intra-Oral Preparation of Titanium Abutments in Order to Obtain Ideal Angulations and Contours
SS White Express Line High Speed Laboratory Metal Finishing Burs
Direct Preparation Of Preexisting Implant Abutments For Case Rehabilitation
Flextime Xtreme: The 80/20 Rule
Fast and Smooth - Efficient Crown Preparation With Carbide Instruments
When Advancing the Bur, One Can Feel the Presence of Dentinal Caries
Precision Trimming and Finishing of Current Dental Restorations Using the Safe End Bur System
Indirect Restorative Tooth Preparation: Extreme Efficiency and Accuracy
Creating Maximum Efficiency and Accuracy In Indirect Restorative Tooth Preparation
Preparation Protocol To Ensure Predictable Aesthetic Restorations
Tooth Preparation Mastering Quality and Efficiency
Fissurotomy: Proactive Treatment for Incipient Decay
Anatomically Adapted Carbide Finishing Burs - Creating Super-Smooth Composite Surfaces in Two Steps
Directions for Use: Dr. David Clark Kit
Placing Traditional Sealants with Enhanced Magnification: Methodology to Increase Both Short-term and Long-term Success - David Clark, DDS
How to Quickly and Conservatively Restore a Natural Shine after Orthodontic Bracket Removal
SS White Surgical Length Oral Surgery Burs: Atraumatic Removal of Teeth for Maximum Bone Preservation

"FISSUROTOMY: Proactive Treatment for Incipient Decay"

George Freedman DDS, FAACD, FACD
Associate Director, Esthetic Dentistry Education Center, SUNY Buffalo
Past President, American Academy of Cosmetic Dentistry

Fay Goldstep DDS, FACD, FADI
American Dental Association Speaker on Dentist Health
Private Practice, Markham, Ontario

Conservative Dentistry

Minimizing the removal of healthy tooth structure during cavity preparation is inherently a desirable dental objective. Since natural enamel and dentin are still the optimal dental materials, minimally invasive procedures must be considered preferable. Conservative dental treatment is also beneficial from a patient's point of view; less discomfort, less need for local anesthetic, and a real prospect that the restoration may last a lifetime.

Amalgam restorations (and frequent redecay) lead to ever larger replacement restorations that have shorter life spans than their predecessors, and may damage adjacent healthy teeth.1 Traditional, non-adhesive amalgam methods and materials are aggressive and highly invasive, requiring the amputation of otherwise healthy enamel and dentin for cavity extension for retention (of the final restoration) and prevention (of recurrent decay).

Figure 1 Fissurotomy Burs (SS White, Lakewood NJ)

Recent developments of innovative materials, techniques, and instruments make conservative dentistry a reality. Adhesive restorations eliminate the need for retentive preparations. Tooth-mimicking composites offer long-lasting restorations with minimum requirements for restorative bulk; little or no healthy tooth material needs to be removed. Early detection keeps restorations small. Innovative instruments such as Fissurotomy burs (SS White, Lakewood, NJ) and microabrasion devices offer the techniques of minimal preparation and maximum patient acceptance (Fig 1).

Early Detection and Treatment

Large, visible dental decay can be readily diagnosed. Over the past several decades, however, the pattern of dental decay has changed dramatically as successful dental education has greatly increased dental awareness. Combined with better and more frequent preventive care, fewer and smaller cavities are typically seen, particularly among the young.

While this is excellent progress for the dental profession (and patients), this trend of fewer and smaller cavities has raised some new questions:

1. How to effectively diagnose smaller lesions in the teeth?
2. Should these smaller lesions be left to grow larger for easier access or should they be intercepted while still small?

Traditionally accepted diagnostic techniques were not designed for small lesions. Almost half of these cavities have a narrow, fluoride-hardened occlusal opening, masking the size and extent of the defect to an explorer2. Histologic cross-section studies have confirmed 25% accuracy in diagnosing decay underlying the occlusal surface using the traditional explorer method 3, hardly an impressive rate of success.

Figure 2 Caries not visible radiographically, but seen on cross-section of the tooth

Radiographic diagnosis can detect caries even where none are observed clinically. All too often, however, there are dental caries that radiographs will not reveal (Fig 2). This is the phenomenon known as hidden caries4,5,6, where the tooth appears caries-free clinically and/or radiographically, but is found to be carious by other diagnostic means. Subsequent cross-sectioning clearly reveals caries that originated at the base of a fissure, and has now spread along the dentino-enamel junction (DEJ).

Electronic diagnostic technologies such as the DiagnoDent and the DiagnoDent Pen (KaVo, Biberach, Germany) (Fig 3) offer an unprecedented 90%+ accuracy in detecting occlusal and interproximal caries. The dilemma of clinically diagnosing decay at an early stage can be a very real problem7,8,9. Explorers and radiographs are simply not adequate tools for diagnosing small caries.

Figure 3 DiagnoDent Pen (KaVo, Biberach, Germany)

Aggressive community water fluoridation compounds the diagnostic dilemma. A Dutch study has determined that the entire Netherlands population (among others) may be overdosing on fluoride 10, and that this may be responsible for an undiagnosed hidden caries level of 15% in the younger population. The surface-hardening fluoride makes the tooth surface resistant to exploration, all the while masking carious activity just below the tooth surface and along the DEJ.

The clinical dentist is faced with two options:

1. Watch the early caries and wait as they enlarge, destroying healthy tooth structure.
2. Aggressively eliminate these early lesions, restoring the teeth to form and function.

The old tradition of "watching" incipient decay is no longer tenable. Extensive recent research has clearly indicated that incipient decay often masks much greater sub-surface carious activity within the tooth. Incipient decay must be intercepted at the earliest possible opportunity to prevent the spread and growth of caries, and to permit the most conservative restoration possible.

The practice of sealing pits and fissures has become widespread11,12,13. Controversy has continued, however, about placing sealants over undiagnosed and/or untreated caries. Since it is often difficult to determine carious activity deep inside fissures, an exploratory Fissurotomy excisional biopsy offers clinical access, conservation of healthy tooth structures, and the certain removal of all decay. The excisional bur remodels the anatomy of the fissure, facilitating operator access and a conservative restoration 14.

Since the Fissurotomy excisional biopsy, usually without anesthetic, causes minimal patient discomfort, patient acceptance is high, and dentists can readily attain their conservationist goals.

Conservative Preparation

The goals of conservative pit and fissure preparation are quite simple:

1. Recontouring the fissure and pit anatomy for greater access and visibility.
2. Exploring the cavity to ensure that no decay remains undetected.
3. Conservative (but complete) caries removal.

The Conservative practitioner has several treatment approaches available.

Small round burs provide a conservative preparation, good explorer access, and require no learning curve. However, they are slow and inefficient in cutting through enamel, often requiring local anesthetic, and leaving undercuts.

Air abrasion provides a conservative removal of tooth structure, good explorer access, and requires minimal anesthetic. The learning curve, however, involves control of direction, cutting depth and spray focus (unlike burs, there is no tactile feedback). Air abrasion equipment may be expensive, and most procedures are rather messy, spewing abrasive dust around the operatory.

Excisional Biopsy burs are specifically designed for fissure recontouring and accessing decay with minimal enamel removal; Fissurotomy burs are fast-cutting, conservative, inexpensive, and familiar to every dentist. In almost all cases, no anaesthetic is required by the patient. The use of the Fissurotomy burs is limited to pits, fissures, and grooves, however, and is not indicated for treatment of larger decay.

Figure 4 HealOzone (KaVo, Biberach, Germany)

Aerotherapy can successfully eliminate any remaining bacteria that are not visually and tactilely identifiable within the enamel lattices and dentinal tubules in and around the prepared fissures. HealOzone (KaVo, Biberach, Germany) has been used effectively by thousands of practitioners worldwide (Fig 4).

The Fissurotomy System

The Fissurotomy burs are the innovative tools of Conservative Dentistry. The bur size and shape are designed specifically for treating pit and fissure lesions. The head length of the bur is 2.5mm, limiting the preparation to just below the DEJ (conservation). The bur’s tapered shape means that the cutting tip encounters very few dentinal tubules, and minimizes heat build-up and vibration. Since the Fissurotomy bur cuts mostly enamel, patient discomfort is minimized and local anesthetic is unnecessary. Comparing Fissurotomy and standard 330 burs demonstrates the decreased invasiveness of the new design (Fig 5A and 5B). Traditional cutting burs, accessing deeper caries, remove far more enamel at any cutting depth than Fissurotomy burs, which have been anatomically-designed to enlarge fissures, eliminating small caries without removing healthy enamel or dentin.

Figure 5A and 5B Standard 330 bur (left). Anatomically designed Fissurotomy bur (right)

Conservative cavity preparation must be matched with suitable restorative materials. Today, the best direct enamel replacement is composite resin. Since the typical Fissurotomy preparations are narrow, long, and irregularly deep cavities, it is essential that the restorative material flow easily into all the nooks and crannies. The dental material of choice for this type of preparation is an adhesive, highly-polishable flowable composite resin such as Venus Flow (Heraeus Kulzer, Hanau, Germany). While hybrid composites are stronger and more wear-resistant than flowables, they may not penetrate the intricate geometry of the narrow preparation.

The Fissurotomy Technique

1. Probe all pit and fissure areas; while there is no apparent decay, the explorer is "sticky" in the fissures (Fig 6).
2. Using the Fissurotomy bur, perform an excisional biopsy of all the carious and suspect fissure areas (Fig 7). Check for remaining decay. Preparation may be left moist or dry.
3. Apply 7th seventh generation iBond (Heraeus Kulzer, Hanau, Germany) (Fig 8), to the preparation, and air-dry completely. Light cure.
   
   

   Figure 6 Explorer finds “sticky” fissure

   Figure 7 Fissurotomy preparation of fissure

   Figure 8 iBond adhesive (Heraeus Kulzer, Hanau, Germany) is applied

   
   
4. Inject Venus Flow into the preparation (Fig 9). Note the excellent adaptation of the restorative material to the cavity walls. Light cure.
5. Apply Seal ‘N Shine (Pulpdent, Watertown, MA, USA) to seal and polish the surface (Fig 10).
6. The completed Conservative restoration is compared to the original carious tooth (Fig 11a and 11b).
   
   

   Figure 9 Explorer finds “sticky” fissure	Figure 10 Seal ‘N Shine (Pulpdent, Watertown MA, USA) seals surface	Figure 11a Prior to treatment
   Figure 11b After treatment	Figure 12 Close-up of finished restoration

   
   Note the conservative width of the restoration (1/8-1/10 the intercuspal distance) as compared to a conventional small amalgam (1/3-1/2 the intercuspal distance). The entire procedure was completed without the need for local anesthetic in less than five minutes (Fig 12).

The Fissurotomy technique offers an innovative bur design and restorative system that provides better, faster and easier treatment and patient comfort, using familiar instrumentation.

Summary

Conservative Dentistry offers a major advance for the dentist, the profession, and particularly for the patient, involving early detection and complete elimination of all accessible and non-accessible caries. Untreated caries, whether advanced or incipient, can be extremely and very rapidly destructive. Early proactive interception of decay maintains dental health, and caries-resisting restorations that can last a lifetime.

References

1. Mertz-Fairhurst EJ, Ergle JW. Cariostatic and ultraconservative sealed Class I restorations: nine year results. IADR Abstract #2513 J Dent Res 1994;73:416
2. Nagano T. The form of pit and fissure and the primary lesion of caries. Dent Abstr. 1960;6:426.
3. Al-Sehaibany F, White G, Raney JK. J Clinical Pediatric Dentistry 1996; 20(4):293-298
4. Wenzel A, et al. Radiographic detection of occlusal caries in non-cavitated teeth. Oral Surg Oral Med Oral Pathol. 1991; 72:621-626
   
5. Weerheijm KL, Gruythuysen RJM, van Amerongen WE. Prevalence of hidden caries. J Dent for Children 1992: 408-412
   
6. Ricketts D, Kidd E, Weerheijm KL, de Soer H. Hidden caries: What is it? Does it exist? Does it matter? International Dental Journal 1997; 47:259-265
   
7. Ismail AI. Clinical diagnosis of precavitated carious lesions. Community Dental Oral Epidemiol 1997;25:13-23
   
8. Verdonschot EH et al. Performance of some diagnostic systems in examinations for small occlusal carious lesions. Caries Res 1992; 26:59-64
   
9. Weerheijm KL et al. Sealing of occlusal hidden caries lesions: an alternative for curative treatment? Journal of Dentistry for Children 1992:263-267
   
10. Kalsboek H et al. An gepast advies over het gebruik van fluoride. Ned Tendheeldkd 1990;97:239-242
11. ??
12. Handelman S, Washburn F, Wooperer P. Two-year report of sealant effects on bacteria in dental caries. J AM Dent Assoc. 1976;93:967-970.
    
13. Handelman S. Effect of sealant placement on occlusal caries progression. Clin Prevent Dent 1982;4:11-16
    
14. Mertz-Fairhurst E, et al. Cariostatic and ultraconservative sealed restorations: six-year results. Quintessence Int. 1992;23:828-838.
    
15. Do Rego MA, Araujo C. A 2-year clinical evaluation of fluoride containing pit
    and fissure sealants placed with an invasive technique. Quintessence Int. 1996:27(2);99-103.