coronoplasty Guided by: presented by: Dr. s. c. gupta dr. virshali gupta
contents Introduction Definition Indications objectives Sequencing coronoplasty in treatment planning Methods Criteria for judging the outcome Conclusion references
introduction Tooth position and arch are maintained by the balance among the forces of occlusion and oral musculature. When this balance gets disturbed, changes in the functional environment may be deleterious to the periodontium. Local environment of the periodontium is affected by the occlusion of the teeth. One of the environmental pollutants that have an adverse impact on periodontium is the altered occlusal force.
definition Coronoplasty is the mechanical elimination of occlusal supra contacts that may be present during functional movements. Selective reduction of occlusal areas to establish functional relationship favorable to the Periodontium by reshaping the teeth (grinding).
indications TRAUMA FROM OCCLUSION: If the trauma is limited to a single tooth or a few teeth- localized coronoplasty. PREVENTIVE OCCLUSAL ADJUSTMENT: the correction of what appear to be abnormal occlusion, for the purpose of preventing future damage – is not recommended.
Objectives Change in pattern and degree of afferent impulses Reducing the excessive tooth mobility Beneficial change in the pattern of chewing or swallowing Multidirectional mandibular movement patterns Verticalization of occlusal forces on tooth
Sequencing coronoplasty in treatment planning Elimination of gingival inflammation and pocket depth Occlusal analysis Informed consent
Occlusal analysis Diagnostic models should be made. Mounting of casts on an articulator using facebow transfer Trial adjustment of occlusion on casts. Material used for occlusal analysis Occlusal indicator wax Marking ribbon Articulating paper
methods a. DETERMINING THE END POINT OF CORONOPLASTY B. Selecting occlusal guidance scheme. 1) Balanced occlusion The simultaneous contacting of maxillary and mandibular teeth on right and left and in the posterior and anterior occlusal areas in centric and eccentric positions. In patients with periodontal disease, molars with unilateral non working side contact showed significantly greater loading forces, greater mobility, bone loss and pocket depth.
2) Canine protected occlusion During lateral mandibular movement, the opposing upper and lower canines of the working side contact thereby causing disclusion of all posterior teeth on working and balancing sides. 3) GROUP FUNCTION Multiple contact relationship b/w maxillary and mandibular teeth in lateral movement of working side, where by simultaneous contacts of several teeth is achieved and act as a group to distribute forces. Both functional and parafunctional occlusal forces exceed those in canine function, so it is not indicated for periodontally compromised dentitions.
Occlusal adjustments Clinical goals To reduce the supra contacts so as to create unobstructed closure of cusps into fossae and marginal ridges, while at the same time conserving original crown structure. The correction of occlusal supracontacts consists of Grooving Spheroiding Pointing
GROOVING SPHEROIDING POINTING
Sequence of coronoplasty Retrusive prematurities are eliminated. Adjust ICP ( intercuspal position) to achieve stable, simultaneous contacts. Test for excessive occlusal contact on the incisors in ICP. Elimination of posterior protrusive contacts. Reduce mediotrusive (balancing) prematurities Laterotrusive prematurities Gross occlusal disharmonies Recheck contact relationship. Polish all depressed surfaces to make the patient feel comfortable, the occlusal surfaces are smoothened and polished.
Criteria for judging the outcome No asymmetric shift from RCP to ICP. Light contact or no contact between incisor teeth and firm contact between as many posterior teeth as possible. Patient perceives even bilateral contact when closing the teeth to ICP. Sharp occlusal sounds when patient taps slowly and firmly into ICP. Molar excursive supracontacts are neutralized or significantly reduced for unrestricted glide paths. Tooth guidance under and protrusive excursions is smooth and without effort. The displacement of mobile teeth is minimized under closure and gliding movements.
CONCLUSION The main objective in occlusal therapy is to maintain or achieve occlusal stability. The first concern in occlusal treatment planning is whether to alter the mandibular position by coronoplasty. If the mandibular position is judged to be adequate, the goal is to maintain the existing occlusion to remove isolated interferences in the course of therapy. There is an evidence that coronoplasty provides better stability. The occlusion must be checked periodically and the patient should be advised accordingly.
references Fermin J: carranza michael G. Newmann clinical periodontology 8th edition. W.B. Saunders 1999. Dr. K. Malathi, Dr. A.J. Anand, Dr. R. Karthikeyan, Dr. Sagar Garg, coronoplasty, IOSR journal of dental and medical sciences (IOSR-JDMS) : volume 13, issue 9 ver. I (sep. 2014), PP 64-67. Ramford SP occlusion indent I : 20;1973