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Pit and Fissure sealant
• Fissure Sealant is a simple and highly effective method to prevent pit and fissure decay. It is a liquid plastic is flowed over the occlusal surface of the tooth where it penetrates the deep fissure to fill areas that cannot be cleaned with the tooth brush.
• Fluoride are highly effective in reducing the number of carious lesion occurring on the smooth surface of enamel and cementum, unfortunately fluoride are not equally effective in protecting the occlusal pits and fissures where 95%of all carious lesions occurs.
Historical back ground
• In 1895 Wilson reported the placement of cement in pits and fissure to prevent caries.
• In 1929 bodecker suggested that deep fissure could e broadened with a large round bur to make the occlusal area more self cleaning, this procedure called enamel plasty.
• Hyatt in 1923 and again in 1936 advocated prophylactic odontotomy,
• In the late 1960 and early 1970, an other option became available in the use of pits and fissure sealant with this option a liquid plastic is flowed over the occlusal surface of the tooth where it penetrates the deep fissure to fill areas that cannot be cleaned with the toothbrush
Materials used in fissure sealant
early materials used as fissure sealant (1904-1950) are:
• silver nitrate
• zinc phosphate/ amalgam ( prophylactic odontotomy).
• black copper cement.
• The newer material (1966-present day):
• Cyanoacrylate resin
• Urethane resins
• Bis-GMA resins consider most successful one in caries prevention.
• Glass ionomer cements
• Resin- modified glass ionomer cements
• Glass Ionomer cement (GICs) are used as sealant material. These materials are effective as resin-based material in preventing caries. However, class ionomer cement 1. wears a faster rate than a conventional resin sealant,2. take longer to place than conventional resin sealant,3. and this adds to the cost of the procedure.
Glass ionomer cement have the advantage that they release fluoride into the adjacent enamel and thus have the potential to prevent caries in these sites compared with fluoride- containing resin-based material
• Another advantage of GlCs is that the material can be placed on the occlusal surface of partially erupted teeth that are difficult to isolate and thus seal better than using conventional resin materials, however even if only partially retained, in situ they act as fluoride reservoir and there is evidence to show that material may be retained well into the depth of the fissure.
• resin- based materials that may be used as sealants are
• Filled or unfilled resins
• Chemical or light-cured resins
• Tinted or opaque resins
• Resins GICs or resin-modified GICs
• Fluoride- releasing or fluoride- free
Selection criteria
• It is recommended that those patients selected to receive sealants meet the following requirements:
• Be dependable on recall appointments
• Be motivated and effective in caries control
• Have low caries activity with few proximal lesions
• Tooth oriented indication for the use of pits and fissure sealants are:
• Caries free (sound) with steep cuspal inclines
• Deep, narrow pits and fissures
• Recently erupted teeth (within three years).
Because no harm can occur from sealing, when in doubt seal.
• Other considerations in tooth selection:
• Age 3 and 4 years are the most important times for sealing the deciduous teeth.
• Age 6-7 years for the upper and lower first permanent molars.
• Age 11-13 years for the upper and lower second permanent molars and premolars.
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• Therefore the decision to place sealant on sound teeth based on:
• Oral hygiene of the patient
• Individual history of dental caries
• Dietary habits
• Patient cooperation and reliability in keeping recall appointments
• Tooth type and tooth morphology
• Concerning the teeth of the adult, the sealant should be placed if there is evidence of existing or impeding caries susceptibility as would occur following excessive intake of sugar or as a result of a drug or radiation induced xerostomia. In all cases it s the disease susceptibility of the tooth that should be addressed not the age of the individual.
• Contraindications of pit and fissure sealant.
• Carious pits and fissures
• Shallow and broad fissures in caries free teeth of patient who have no sign of caries activity
• Teeth with many proximal lesions
• Patient behavior does not permit use of adequate dry field technique through out the procedure
• Reasons given by clinicians against the use of sealants:
– No effective- sealant materials lost
– Danger of sealing in dental caries
– Not effective, seal more than ever become carious
-Acid etched leave the remainder of the surface vulnerable.
Requisites for sealant retention
• These are the four commandments for successful sealant placement, and they cannot be violated.
For sealant retention the surface of the tooth must
• Have a maximum surface area (through acid etched).
• Be clean.
• Be absolutely dry at the time of sealant placement.
• Have deep irregular pits and fissures.
Practical application.
• 1.All heavy stains deposits and debris should be removed from the occlusal surface.
• 2.Isolation of the pits and fissure and tooth surface.
• 3.Etching the surface to be sealed
• 4. Rinsing the etched area with water spray
• 5. Application and hardening of the sealant
6. Evaluation
7.Adjustment
8.Reevaluation (recall)
Retention of the sealant.
• Plastic sealant is retained better on recently erupted teeth than in teeth with a more mature surface.
• They are retained better on mandibular than on the maxillary teeth, this is possibly due to the fact that the lower teeth are :
• more accessible.
• direct sight is possible.
• isolation of the teeth is easier.
gravity aids the flow of sealant in to the fissure
• The number of retained sealant decreases, over the first 3 months, the rapid loss of sealant is probably
1.due to faulty technique in placement.
2.then after that the sealant loss probably being due to abnormal masticatory stresses.
3. After a year or so the sealant become very difficult to see especially if they are abraded to the point that they fill only the fissures.
• Teeth that have been sealed and then have lost the sealant have had fewer lesions than control teeth. This possibly due to the tags that are retained in the enamel after the bulk of the sealant has been sheared from the tooth surface.
The colored versus clear sealant
• Both clear and colored sealant are available, they vary from translucent to white yellow, blue and pink.
• The selection of colored versus a clear sealant is a matter of individual preference.
• The colored products
1. Permit more precise placement of the sealant with the visual assurance that the periphery extend halfway up the inclined planes.
2. Retention be more accurately monitored by both the patient and the dentist.
On the other hand, clear sealant may be considered more esthetically acceptable
Photo-cured versus self-cured sealant
The main advantages of the photo cured sealant is that
1.The operator can initiate polymerization at any suitable time.
2.Polymerization time is shorter with photo cured product than with self-curing sealants.
3.Visible light curing, gives the clinician more control over the setting of the material.
4.The photo cured process dose require the light source. Conversely, the self curing resins do not require an expensive light source.
Sealants versus amalgams
1.sealant used to prevent occlusal lesions, while amalgam used to treat occlusal lesions.
2.studies shows that sealant application need 6-9 min. while amalgam need 13-15 min.
3. commonest cause for sealant replacement is loss of material while for amalgam replacement is marginal decay.
4. to replace the sealant only resealing is necessary and no damage to tooth occur while for amalgam replacement usually require cutting more tooth structure with each replacement.
5. painless procedure during sealant placement, while during amalgam replacement may accompanied with pain.
Barriers to sealant usage.
The frequency of using fissure sealant is low among majority of the dentist, reasons for this are:
• economic consideration.
• lack of technical skill.
• need more research before acceptances.
• most dentist are treatment oriented, rarely do the explain to the patient the advantages of sealant over dental restoration.
• the concept and actions of prevention are not being fully implemented in dental schools, dental school faculties need to be educated about the effectiveness and methods of applying sealants.
• lack of knowledge among public about the effectiveness of sealant result in lack of demand for the product
Management of questionable carious fissures
Non-invasive technique for the management of the questionable (incipient) carious fissure involves
• plaque control and removal
• Reevaluation at individually assessed recall intervals
• If a good plaque control is not achieved a fissure sealant should be placed.
• Even though professional and home based plaque control is considered as the most important treatment for the questionable carious fissure.
Preventive resin restoration
• There are options for the preventive resins restoration based on the extent and depth of the carious lesion these options are:
• Comprises suspicious pits and fissures where the decalcification is noted and the patients is in a high risk category.
1.The carious removal is limited to enamel using the smallest bur to remove the carious material from the bottom of a pit and fissure.
2.The defect can be filled with an acid etch retained composite
3.Following this operation sealant is then placed over the polymerized material as well as flowed over the remaining fissures. A side from protecting the fissures from future caries, it also possibly protect the composite from abrasion.
• Incipient lesion in dentin that is small and confined
• Following preparation that include dentin to a slight extent.
• The cavity is restored with liner (example GIC) to replace the dentin.
• Topped off with composite resin to replace the enamel
• A fissure sealant is used to protect the remaining fissure system.
المادة المعروضة اعلاه هي مدخل الى المحاضرة المرفوعة بواسطة استاذ(ة) المادة . وقد تبدو لك غير متكاملة . حيث يضع استاذ المادة في بعض الاحيان فقط الجزء الاول من المحاضرة من اجل الاطلاع على ما ستقوم بتحميله لاحقا . في نظام التعليم الالكتروني نوفر هذه الخدمة لكي نبقيك على اطلاع حول محتوى الملف الذي ستقوم بتحميله .
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