MetLife designates this activity for 2.0 continuing education credit for the review of this Quality Resource Guide and successful Quality Resource Guide completion of the post test. SECOND EDITION Managing the Patient with a Worn Dentition Author Acknowledgements Figure 1 Educational Objectives Paul A. Hansen, DDS Associate Professor, Following this unit of instruction, the practitioner Director Prosthodontic Section University of Nebraska should be able to: College of Dentistry 1. Describe the etiologies for the worn dentition. N. Blaine Cook, DDS Clinical Associate Professor 2. Identify the types of tooth wear. Director Graduate Operative Dentistry 3. Describe how to perform an accurate A classic example of horizontal bruxism. All Indiana University School of Dentistry diagnostic mounting. teeth show wear and are flat. Drs. Hansen and Cook have no relevant 4. Explain the use of the diagnostic mounting in financial relationships to disclose. diagnosis and treatment planning. Figure 2 The following commentary highlights 5. Explain the difference between centric fundamental and commonly accepted relation and maximum intercuspation. practices on the subject matter. The 6. Describe mutually protected occlusion. information is intended as a general overview and is for educational purposes only. This 7. Understand the proper sequence for restoring information does not constitute legal advice, extensive wear cases. which can only be provided by an attorney. 8. Understand how to use modern materials to © Metropolitan Life Insurance Company, prevent continued wear. New York, NY. All materials subject to this copyright may be photocopied for the noncommercial purpose of scientific or educational advancement. Originally published in July 2011. Updated and revised December 2014. Expiration Introduction Figure 3 date: December 2017. The content of nitial examination of a new patient occasionally this Guide is subject to change as new scientific information becomes available. reveals a severely worn dentition characterized by I extensive wear and loss of tooth structure. Function and esthetics are compromised, and the prognosis for MetLife is an ADA CERP Recognized Provider. one or several teeth may be jeopardized if the problem ADA CERP is a service of the American Dental Association to assist dental professionals is not corrected. The complex nature of this condition, in identifying quality providers of continuing Tooth structure loss is due to attrition, but the and its multifactorial etiology, often overwhelms the dental education. ADA CERP does not approve wear pattern is quite different from Figure 1. or endorse individual courses or instructors, general dentist with limited experience in treating such In this example there are sharp shards of enamel nor does it imply acceptance of credit hours by widespread tooth destruction. remaining. This is an example of vertical bruxism. boards of dentistry. Concerns or complaints about a CE provider Loss of tooth structure may be a result of mechanical may be directed to the provider or to ADA wear (attrition, abrasion), chemical attack (erosion, other and results in even tooth wear with the creation CERP at www.ada.org/goto/cerp. also called corrosion1) and/or mechanical stress of sharp wear facets. Abrasion (Figures 4,5) is tooth Accepted Program Provider FAGD/MAGD Credit 11/01/12 - 12/31/16 concentration (abfraction). Attrition is mechanical wear resulting from the friction of an exogenous wear that occurs when opposing teeth rub against material (a bolus of food, toothpaste, or an opposing Address comments to: [email protected] each other during mastication and/or parafunctional ceramic crown) against tooth structure. Chemical MetLife Dental mandibular movements (Figures 1-3). This type of erosion (corrosion) is the loss of tooth structure from Quality Initiatives Program 501 US Highway 22 2,3 wear is limited to areas where teeth contact each exposure to chemicals, usually acids (Figures 6,7). Bridgewater, NJ 08807 www.metdental.com Quality Resource Guide – Managing the Patient with a Worn Dentition 2nd Edition Chemical erosion can be caused by a number of of stomach contents will normally be greater in the Figure 8 different agents. The dissolution of tooth enamel anterior region of the mouth due to the projectile requires an acidic environment. Erosion can begin vomitus and tongue position. The tongue will often at a pH of 5.5.4 Acid can come from gastric contents cover the mandibular anterior teeth protecting either from gastric reflux or bulimia. Regurgitation the mandibular anterior teeth, allowing greater dissolution of the maxillary anterior teeth, especially on the lingual surfaces. 5, 6,7,8,9 Figures 4 and 5 The use of commercial soft drinks and sports This patient demonstrates wide spread loss of tooth structure. The mandibular incisors drinks can also add to the dissolution of enamel. An are not affected as much as the maxillary analysis of the pH of the commercial drinks reveals and posterior teeth. The tongue will protect a low pH with the potential of causing enamel the mandibular incisors from stomach acid. loss.10,11 Abrahamsen refers to the problem with commercial drinks as “Coke-Swishing” and states Figure 9 that the loss of enamel is more prominent in the posterior of the mouth because of tongue position. Cupping or cratering is present with the soft drink erosion and will present sharp enamel edges.2 Abfraction lesions are wedge-shaped cervical defects attributed to tooth flexure during abnormal occlusal loading. The worn dentition is often due to This patient demonstrates significant tooth a combination of attrition, erosion and abfraction.1-3 structure loss on the facial aspect of the mandibular molars. Loss is due to both The clinician must identify and eliminate all etiologic sleeping position and the pooling of stomach Abrasion to the facial of tooth #3 and #6. factors, before restoring the dentition to proper form acid on one side, as well as the use of a Probably due to tooth brush use and function. toothbrush to vigorously brush the right side when stomach acid is present. We often discover that a patient will demonstrate Figures 6 and 7 tooth wear that is a combination of erosion, abrasion and attrition. Figure 8 shows a patient Figure 10 with significant tooth structure loss. He had been diagnosed with gastric reflux problems and was able to communicate the issue. Loss of tooth structure was much greater on the patient’s right side than his left. The patient stated he would have reflux episodes at This photo of right working movement night, and the taste would drive him to immediately reveals a balanced occlusion with working, brush his teeth. He was able to demonstrate that balancing and protrusive contacts. Tooth he would vigorously brush his right side, but barely loss is due to attrition combined with ero- sion and abrasive habits. touch his left side. Erosion combined with abrasion as he brushed his teeth in the presence of gastric acids. He also related to being a right side sleeper, Figure 11 which allowed gastric contents to concentrate in the right side vestibule, creating greater erosion. Figure 10 shows a patient in a right side working movement. Tooth to tooth contact and resultant attrition contributed to the tooth loss on the right side. The patient demonstrates erosion, abrasion, Loss of tooth structure on the occlusal and attrition, resulting is heavy loss of tooth surfaces which do not contact the opposing The patient’s left side is not as affected by arch. structure. Figure 11 shows the left side with little the erosion and abrasive problems. loss of tooth structure in contrast to the right side. www.metdental.com Page 2 Quality Resource Guide – Managing the Patient with a Worn Dentition 2nd Edition Gypsum casts made from accurate alginate Treatment Planning Figure 12 impressions are sufficient for this purpose.12 The hen confronted with a complicated casts should be mounted on a semi-adjustable restorative challenge such as worn articulator with accurate facebow and interocclusal dentition, the clinician should return W records to properly position them on the articulator. to the basics of treatment planning, beginning The facebow (Figure 12) relates the maxillary cast with the patient interview. What is the patient’s to the axis of rotation of the patient’s mandibular chief concern? The inability to eat, tooth sensitivity condyles and the Frankfort horizontal plane (or The use of the facebow will relate the maxil- and poor esthetics are common complaints of the an equivalent third reference point). This allows lary cast to the axis of rotation, the Frankfort patient with a worn dentition. the mounted casts to mimic the patient’s occlusal horizontal plane and the plane of occlusion. Patients provide important information. They relationships and mandibular movements. This mounting can be useful in identifying occlusal may relate a history of bruxism, bulimia, or Over 90% of the population exhibit a discrepancy discrepancies and determining how to correct them. gastroesophageal reflux disease (GERD); though between CR and MI.20-24 These premature contacts individuals with eating disorders might be unwilling Interocclusal records orient the mandibular cast to or interferences can be a causative factor for to disclose these problems. Inquiring into dietary the maxillary cast and are made in centric relation excessive wear of teeth. habits may reveal behaviors such as fresh fruit position (CR). CR is “the relationship of the mandible mulling or the swishing of carbonated beverages, to the maxilla when properly aligned condyle/ Occlusal Analysis which can erode tooth surfaces.2,3 The patient can disc assemblies are in the most anterior superior pposing posterior teeth in an ideal occlusion be asymptomatic and unaware of the presence position against the eminentia irrespective of tooth are located directly over one another so of any of etiologic factors. Referral for medical position or vertical dimension.”13 that occlusal forces load them in an axial evaluation is often indicated in such situations, O In contrast, maximum intercuspation (MI) is an direction (Figures 13 and14).