Tissue Dilatation Lecture Notes PDF

TISSUE DILATATION  TISSUE DILATATION Definition It is the process of pushing the gingival tissue away from the surface temporarily for better examination and accurate impression taking.  INDICATION FOR GINGIVAL TISSUE DILATION: 1- During examination: for better examinat...

TISSUE DILATATION  TISSUE DILATATION Definition It is the process of pushing the gingival tissue away from the surface temporarily for better examination and accurate impression taking.  INDICATION FOR GINGIVAL TISSUE DILATION: 1- During examination: for better examination of the cervical area covered by the free gingival 2- During preparation: for accurate preparation and positioning of the finishing line. In addition, it avoids injury and bleeding from the soft tissue 3- During impression taking: it helps to displace the gingival tissue, in order to expose the preparation margins and the finishing the line. Therefore, an accurate elastic impression can be taken. 4- During finishing and cementation: to get sure that there is no overhanging or open margins for better marginal fitness REQUIREMENT OF TISSUE DILATATION: 1- It must create a proper space horizontally so that: a) The impression material may recorded the tooth structure at the beyond the margins in a vertical direction b) Provides for sufficient strength of impression material to prevent distortion or tearing when the impression is removed or poured with stone REQUIREMENT OF TISSUE DILATATION: 2- To create a clean and dry field free from serum seepage or blood 3- Protects and maintains the health of the supporting periodontal tissue  METHODS OF TISSUE DILATION: I- Mechanical methods II - Mechanical chemical method III- Cordless technique IV- Surgical method  I - MECHANICAL METHODS - It is the first developed method for tissue dilation - Lasts for 24 hours. If left longer, permanent gum recession will occur -Mechanical displacement can be done by: -  1-A COPPER BAND One end of the tube is festooned, or trimmed, to follow the profile of the gingival finish line, which, in turn, often follows the contours of the free gingival margin. The tube is filled with modeling compound, and then it is seated carefully in place along the path of insertion for 24 hours. If left longer, permanent gum recession will occur 2- ZINC OXIDE OR GUTTA PERCHA –PACK -Indicated when the gingival hypertrophy is confined to the interproximal space - The zinc oxide and eguenol are mixed with a piece of gauze and packed in the inter proximal space The gutta percha is softened and - packed in the inter-proximal space - -Left for 24 hours  3- TEMPORARY CROWN - Indicated when gingival hypertrophy is involved more than one surface - The margins must be trimmed so that when the temporary crown is placed., the gingival tissue is displaced without blanching - Left for 24 hours  4- RUBBER DAM - By making a hole in the dam - Provides clean dry field that helps in preparation - -  5- ORTHODONTIC RUBBER BAND: - By using a blunt instrument, the orthodontic rubber band is pushed the free gingival and left for 24 hours, then removed - It may cause trauma to the gingival tissue II- MECHANICAL CHEMICAL METHOD It is the most universal method. It lasts from 5-10 minutes  It is achieved by the use of a chemically impregnated cord. The cord will push the gingival mechanically using a blunt instrument with minimal pressure. while, the chemicals which have astringent action, will stop hemorrhage and bleeding of the gingival tissue The cord cane be treated with either a- Epinephrine 1/1000 b- Epinephrine 8% Otherwise, epinephrine syndrome will result with the following system: increased blood pressure Nervosity Post operative depression They are contraindication in case of cardiac patient c- Aluminum chloride 5%-25% d- Alum solution 100% e- Ferric sulphate 13.3% f- Tanic acid solution 20-100% g- Negatol solution 45%  STEP-BY-STEP PROCEDURE 1. Isolate the prepared teeth with cotton rolls, place saliva evacuators as required, and dry the field with air. 2. Cut a length of cord sufficient to encircle the tooth Do not over-desiccate the tooth, because this may lead to postoperative sensitivity. 3. Dip the cord in astringent solution and squeeze out the excess with a gauze square. An impregnated cord can be placed dry but should be moistened in situ to prevent the thin sulcular epithelium from sticking to it and tearing when it is removed. 4. If a nonbraided cord is used, twist it tightly for easier placement. 5. Loop the cord around the tooth and gently push it into the sulcus with a suitable instrument It is best to start in the interproximal area , because the cord can be more easily placed here than facially or lingually. The instrument should be angled toward the tooth so the cord is pushed directly into the area. It should also be angled slightly toward any cord already packed; otherwise, that portion might be displaced. A second instrument may aid placement 2 inch piece of retraction cod is cut off The cord is twisted to make it as tight and as small as possible  A loop of retraction coed is formed around the tooth and held tautly with the thumb and forefinger Placement of the retraction cord is begun by it into the sulcus on the mesial surface of pushing the tooth, it should also be tacked tightly into the distal crevice The instrument should be angled toward the tooth so the cord is pushed directly into the area. Excess cord is cut off in the mesial interproximal area Placement of the distal end of the cord is continued until it overlaps the mesial. The force of the instrument must be directed toward the cord previously packed DOUBLE CORD TECHNIQUE III- CORDLESS TECHNIQUE  IV-SURGICAL METHOD Indicated when there is generalized gingival hypertrophy and bleeding or to increase the length of the clinical crown. increase the length of the clinical crown  SURGICAL TECHNIQUE: By performing gingivectomy, to the level of the epithelial attachment. Tissue will regenerate to the original height Done by using a scalpel  ELECTRO-SURGERY It is a controlled tissue destruction to achieved a surgical result. Done by allowing a high frequency current to pass through a very small electrode, thus, generating heat. Tissue in contact with the electrode, are destroyed or exposed, finally cut away. The blood vessels are narrowed by coagulation.  DISADVANTAGE: Need experienced hands to avoid destruction of the periodontium due to over deepening of sulcus  CONTRAINDICATION: 1- Patients with pace maker 2- Patients with delayed healing eg. Under radiation therapy 3- Thin attached gingival on the labial surface eg. upper canine ROTARY CURETTAGE : ( GINGIVETTAGE “TROUGHING”) It is a toughing technique using a rotary instrument: It is define as : A limited removal of inner epithelial tissues in the sulcus while creating a chamfer finish line using a torpedo-nosed diamond. Done healthy, inflammation free gingiva to avoid shrinkage of the tissue during healing  REQUIREMENT: -No bleeding on probing -Sulcus depth < 3mm - Adequate keratinized gingival tissues  TECHNIQUE: Firstly, the finishing line is prepared at the level of the gingival crest. Then a torpedo-nosed diamond, with generous water spray, is used to extend the finishing line beneath the gingival sulcus.  LASER GINGIVAL DISPLACEMENT: Removal of epithelial tissue using laser Advantages: Faster More efficient Painless More sterile Bloodless, less invasive, less painful post-operatively Thank you