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Phonetics and tongue position to improve mandibular denture retention: A clinical report
Phonetics and tongue position to improve mandibular denture retention: A clinical report David M. Bohnenkamp, DDS, MS,a and Lily T. Garcia, DDS, MSb University of Texas Health Science Center at San Antonio Dental School, San Antonio, Tex The fabrication, use, and wear instructions for complete dentures are often the factors determining success. The dentist must help guide the mental attitude of the skeptical patient to foster acceptance and success of complete dentures. A “feeling of looseness” may be a condition experienced while patients learn to wear a new mandibular complete denture. Some patients may not understand the reasons given by dentists for the lack of retention of a new mandibular denture. This type of patient requires more explanation, more advice, and more instruction. A phonetic training technique, to demonstrate to the patient how to retain and stabilize the mandibular denture, may be needed for some denture patients. This article reports the clinical use of phonetics and its effect on tongue position to improve the retention and stability of a mandibular complete denture. (J Prosthet Dent 2007;98:344-347) One of the most difficult challenges for clinicians who fabricate and insert complete dentures is to explain to a patient the lack of retention for a new mandibular complete denture. Anatomical, physiological, and/or behavioral problems associated with some patients are commonly offered as reasons for a nonretentive or “loose” mandibular complete denture. Unfortunately, the denture patient may see these reasons as excuses, especially if a previous mandibular denture felt more retentive. The position, size, and activity of the tongue are important factors in denture success or failure. Wright and coauthors suggested that the ideal resting position of the tongue is for the apex of the tongue to just touch the lingual surfaces of the mandibular anterior denture teeth, with the lateral surface touching the posterior teeth of the denture.1 The authors reported that this position of the tongue would enhance mandibular denture stability. However, a retruded tongue at rest was considered by the authors to be an unfavorable position for denture stability (Fig. 1).
Several authors have suggested that where marked mandibular residual ridge resorption occurs it may be desirable to use the tongue and the buccinator muscle to fix the mandibular denture in place by appropriate design of the width and form of the denture flanges.2 It has been reported that a border seal on the floor of the mouth can compliment seals in the buccal vestibular spaces to enhance denture retention. Extension of the mandibular denture over the resting tissues of the sublingual crescent area completes the border seal and increases the surface area covered by the mandibular denture, resulting in greater retention by allowing the tongue to aid in maintaining the denture in position.3 Shanahan described tongue position as an important factor in managing a patient with an unfavorable mandibular residual ridge.4 He wrote that the ideal tongue position could be described as being forward and resting on the superior portion of the mandibular anterior residual ridge when the patient casually opens the mouth (Fig. 2). It was reported that
such a position would effectively form a lingual border seal. Shanahan also indicated that a retruded tongue makes it almost impossible to establish this seal. Other authors have recommended that during border molding of a custom tray for fabrication of a mandibular denture, the tongue should be in a normal rest position with the tip lightly touching the lingual surfaces of the mandibular anterior teeth.3 The authors reported that variations in shape and anatomy dictate the use of different impression techniques and modifications in flange design to make a clinically successful mandibular denture.3,5,6 Rahn and Heartwell wrote that in its activity the tongue frequently unseats the mandibular denture. They believed that training the tongue would aid in stabilizing a complete mandibular denture.7 The authors suggested that when the mouth is open, the tip of the tongue should be moved forward until it rests against the inside of the denture flange and the mandibular anterior denture teeth. They noted that this action helped to seat the mandibular denture, and once the
Assistant Professor, Department of General Dentistry. Professor and Chair, Department of Prosthodontics.
a
b
The Journal of Prosthetic Dentistry
Bohnenkamp and Garcia
345
November 2007
1 Unfavorable retruded position of tongue for retention and stability of mandibular complete denture. patient formed this habit, it would become automatic. However, certain denture patients may require more explanation, more advice, and more instruction than simply being told what to do with their tongues. A phonetic training technique to properly position the tongue and buccinator muscles may be needed for some denture patients to learn their role in denture retention. This article reports on the clinical use of phonetics and tongue position during fabrication and at insertion to improve the retention and stability of a newly fabricated mandibular complete denture.
CLINICAL REPORT A 52-year-old woman complaining of ill-fitting and nonretentive complete dentures was referred by a local dentist to the Department of Prosthodontics at the University of Texas Health Science Center Dental School for evaluation and treatment. The patient’s chief complaint was that “my lower denture is loose and doesn’t fit right.” A review of the medical history revealed that the patient was in overall general good health with some arthritis in her arms and legs currently being treated with medications prescribed by her physician. A review of the dental history revealed that the patient had been edentulous in the maxilla and mandible for approximately 18 years. The patient was currently wearing her third set of complete dentures. The
Bohnenkamp and Garcia
2 More favorable position of tongue for retention and stability of mandibular complete denture.
first set initially made for the patient was remade due to an “unfavorable appearance”. The remade complete dentures were deemed “favorable” by the patient, but were again remade approximately 3 years prior due to her complaint of a “very loose lower denture” and the need for her to use an excessive amount of denture adhesive to retain the mandibular denture. The patient stated she was not satisfied with the third set of dentures, although she had tolerated the “loose fit” for the past 3 years. Observations of the patient’s current dentures revealed fair masticating efficiency, esthetics, and phonetics, a decreased occlusal vertical dimension, and poor retention and stability of the mandibular denture. Clinical and radiographic examination of the patient revealed good neuromuscular skills, normal mandibular movements, a highly resorbed mandibular residual ridge, and normal tongue size with a square tongue form and retruded tongue position (Fig. 3). The patient was advised of the clinical findings and alternative treatment choices, including fabrication of new maxillary and mandibular dentures or implant placement and conversion of her mandibular denture to an overdenture with attachments. The patient opted to have new dentures fabricated, as she did not desire implants placed at this time even though she was told that the lack of retention and stability for the mandibular den-
ture was best approached with an implant-retained overdenture. A fair prognosis for the new dentures was given to the patient due to her highly resorbed mandibular residual ridge and retruded tongue position and the patient’s expectations for greatly improved retention and stability of the new mandibular denture. Fabrication of new maxillary and mandibular complete dentures for the patient proceeded, with special emphasis on retention and stability of the mandibular denture. Border molding of custom impression trays (Triad VLC Denture Base Material; Dentsply Intl, York, Pa) and making of accurate definitive impressions (Impregum; 3M ESPE, St. Paul, Minn) to capture and cover appropriate anatomical features were accomplished to enhance retention of the dentures.1-7 During border molding and making of the mandibular definitive impression, the patient was instructed to pronounce the sound “e”, as in the word “knee”, to aid in positioning the tongue and buccinator muscles to develop a peripheral seal of the mandibular denture borders. Maxillomandibular records and a trial insertion of the dentures were completed at subsequent separate appointments. At each appointment, the patient was reminded of the “challenge” to be accepted to overcome the physical and anatomical features that worked against retention and stability of the mandibular denture.
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Volume 98 Issue 5
3 Intraoral view of unfavorable retruded tongue position of patient with highly resorbed mandibular residual ridge. Patient complains of nonretentive mandibular complete denture.
4 Intaglio surface of newly fabricated mandibular denture for edentulous patient with highly resorbed mandibular residual ridge and unfavorable tongue position. The patient was repeatedly informed of the important role that tongue position and facial muscles have in improving retention and stability of the new mandibular denture. On several occasions, the patient was instructed to pronounce the sound “e” to help train and coordinate the positions of the tongue and buccinator muscles. At insertion of the new maxillary and mandibular dentures, the patient initially appeared skeptical, but soon acknowledged that through the use of phonetics she was able to improve the retention and stability of her new mandibular complete denture. A clinical remount of the dentures was done to modify and refine the monoplane occlusion. Minimal adjustments of the denture base flanges and intaglio
surfaces were subsequently made to the dentures at 24-hour, 72-hour, 1week, and 2-week postinsertion appointments (Fig. 4). At completion of treatment, the patient acknowledged that she was comfortable and pleased with the fit, retention, function, and esthetics of the new dentures.
DISCUSSION In a study conducted by van Waas, no correlation was found between patient satisfaction with complete dentures and any of the variables concerning the physical condition of the patient’s mouth, including the quality of the mandibular residual ridge.8 He concluded that severe atrophy of the mandibular ridge is not necessarily an
The Journal of Prosthetic Dentistry
indication for preprosthetic surgery or implants. The author reported that many patients in the study with atrophic residual ridges did not have complaints, even with specific problems such as looseness of the mandibular denture. Unfortunately, the patient in this clinical report was dissatisfied and did complain of excessive movement and no retention of her mandibular complete denture. When a dentist provides complete dentures to a patient, he or she must accept the responsibility of educating the patient about their role in a special training program to assist with particular problems with new dentures.9 Stability and retention of a mandibular complete denture may be considered a challenge both to the dentist and the edentulous patient, but the success or failure of the definitive outcome is determined by the patient’s response to the challenge. Several authors have noted that between groups of young and old denture patients, a correlation exists between denture retention and learning processes.10 If a patient can be taught to position the tongue in a purposeful manner to improve retention and stability of a mandibular denture, then the patient may master the challenge and resolve their chief complaint. Constant repetition through the use of coordinated exercises can help a patient learn muscular activity patterns that aid in the retention of a “loose” mandibular denture. Because of the wide range of movements of the mandible, tongue, and facial musculature, the mandibular denture presents the greatest difficulty in learning to use complete dentures.11 Researchers have studied mandibular complete dentures and concluded that muscle activity transcended in importance all other factors responsible for retention, especially in relation to the mandibular denture where the residual ridge is highly resorbed.12 The activity of the lips and cheeks on the labial and buccal surfaces of the mandibular denture, functioning concomitantly with
Bohnenkamp and Garcia
347
November 2007 the delicate lingual tongue contacts, plays an important role in retention. Patients can be taught to pronounce certain phonetic sounds to enable their tongue and buccinator muscles to perform the actual mechanics needed to improve retention and stability of the mandibular denture. As demonstrated by an edentulous patient, the production of the sound “e”, as in the word “knee”, helped to train the patient to use the tongue and buccinator muscles to retain and stabilize a new mandibular denture (Fig. 5). It is important to recognize that coordinated muscle activity was developed with the use of phonetics to teach the patient how to improve the retention of the new mandibular denture.
SUMMARY The ability of an edentulous patient to successfully wear and function with a new mandibular denture can be a frequent complaint that is most often the result of a lack of patient adeptness or unfavorable tongue habits. Some patients have a natural talent in successful use of their mandibular denture; others must learn how to acquire this skill. Patient education relative to phonetics and a favorable tongue position and their role in improving mandibular denture retention should be provided to patients as part of the clinical fabrication and insertion of complete dentures.
5 Edentulous patient pronouncing “e”, as in “knee”, to learn to use tongue and buccinator muscles to retain and stabilize new mandibular complete denture.
REFERENCES 1. Wright CR, Muyskens JJ, Strong LH, Westerman KN, Kingery RH, Williams ST. Study of the tongue and its relation to denture stability. J Am Dent Assoc 1949;39:269-75. 2. Brill N, Tryde G, and Cantor R. The dynamic nature of the lower denture space. J Prosthet Dent 1965;15:401-18. 3. Azzam MK, Yurkstas AA, and Kronman J. The sublingual crescent extension and its relation to the stability and retention of mandibular complete dentures. J Prosthet Dent 1992;67:205-10. 4. Shanahan TE. Stabilizing lower dentures on unfavorable ridges. J Prosthet Dent 1962;12:420-4. 5. Tryde G, Olsson K, Jensen SA, Cantor R, Tarsetano JJ, Brill N. Dynamic impression methods. J Prosthet Dent 1965;15:102334. 6. Lott F, Levin B. Flange technique: an anatomic and physiologic approach to increased retention, function, comfort, and appearance of dentures. J Prosthet Dent 1966;16:394-413. 7. Rahn AO and Heartwell CM. Textbook of Complete Dentures. 5th ed. Baltimore: Wil-
liams & Williams; 1993. p. 121-9. 8. van Waas MA. The influence of clinical variables on patients’ satisfaction with complete dentures. J Prosthet Dent 1990;63:307-10. 9. Bell DH Jr. Prosthodontic failures related to improper patient education and lack of patient acceptance. Dent Clin North Am 1972;16:109-18. 10.Brill N, Tryde G, and Schubeler S. The role of learning in denture retention. J Prosthet Dent 1960;10;468-75. 11.Naylor JG. What the patient should know about complete dentures. J Prosthet Dent 1959;9:832-40. 12.Brill N, Tryde G, and Schubeler S. The role of exteroceptors in denture retention. J Prosthet Dent 1959;9:761-8. Corresponding author: Dr David M. Bohnenkamp Mail Code 7897 7703 Floyd Curl Dr San Antonio, TX 78229 Fax: 210-567-1157 E-mail: [email protected] Copyright © 2007 by the Editorial Council for The Journal of Prosthetic Dentistry.
New Product News The January and July Issues of the Journal carry information regarding new products of interest to prosthodontists. Product information should be sent 1 month prior to ad closing date to: Dr Carol A. Lefebvre, Editor, The Journal of Prosthetic Dentistry, School of Dentistry, AD-2943, Medical College of Georgia, Augusta, GA 30912-1255. Product information may be accepted in whole or in part at the discretion of the Editor and is subject to editing. A black-andwhite glossy photo may be submitted to accompany product information. Information and products reported are based on information provided by the manufacturer. No endorsement is intended or implied by the Editorial Council for The Journal of Prosthetic Dentistry, the Editor, or the publisher.
Bohnenkamp and Garcia
Several authors have suggested that where marked mandibular residual ridge resorption occurs it may be desirable to use the tongue and the buccinator muscle to fix the mandibular denture in place by appropriate design of the width and form of the denture flanges.2 It has been reported that a border seal on the floor of the mouth can compliment seals in the buccal vestibular spaces to enhance denture retention. Extension of the mandibular denture over the resting tissues of the sublingual crescent area completes the border seal and increases the surface area covered by the mandibular denture, resulting in greater retention by allowing the tongue to aid in maintaining the denture in position.3 Shanahan described tongue position as an important factor in managing a patient with an unfavorable mandibular residual ridge.4 He wrote that the ideal tongue position could be described as being forward and resting on the superior portion of the mandibular anterior residual ridge when the patient casually opens the mouth (Fig. 2). It was reported that
such a position would effectively form a lingual border seal. Shanahan also indicated that a retruded tongue makes it almost impossible to establish this seal. Other authors have recommended that during border molding of a custom tray for fabrication of a mandibular denture, the tongue should be in a normal rest position with the tip lightly touching the lingual surfaces of the mandibular anterior teeth.3 The authors reported that variations in shape and anatomy dictate the use of different impression techniques and modifications in flange design to make a clinically successful mandibular denture.3,5,6 Rahn and Heartwell wrote that in its activity the tongue frequently unseats the mandibular denture. They believed that training the tongue would aid in stabilizing a complete mandibular denture.7 The authors suggested that when the mouth is open, the tip of the tongue should be moved forward until it rests against the inside of the denture flange and the mandibular anterior denture teeth. They noted that this action helped to seat the mandibular denture, and once the
Assistant Professor, Department of General Dentistry. Professor and Chair, Department of Prosthodontics.
a
b
The Journal of Prosthetic Dentistry
Bohnenkamp and Garcia
345
November 2007
1 Unfavorable retruded position of tongue for retention and stability of mandibular complete denture. patient formed this habit, it would become automatic. However, certain denture patients may require more explanation, more advice, and more instruction than simply being told what to do with their tongues. A phonetic training technique to properly position the tongue and buccinator muscles may be needed for some denture patients to learn their role in denture retention. This article reports on the clinical use of phonetics and tongue position during fabrication and at insertion to improve the retention and stability of a newly fabricated mandibular complete denture.
CLINICAL REPORT A 52-year-old woman complaining of ill-fitting and nonretentive complete dentures was referred by a local dentist to the Department of Prosthodontics at the University of Texas Health Science Center Dental School for evaluation and treatment. The patient’s chief complaint was that “my lower denture is loose and doesn’t fit right.” A review of the medical history revealed that the patient was in overall general good health with some arthritis in her arms and legs currently being treated with medications prescribed by her physician. A review of the dental history revealed that the patient had been edentulous in the maxilla and mandible for approximately 18 years. The patient was currently wearing her third set of complete dentures. The
Bohnenkamp and Garcia
2 More favorable position of tongue for retention and stability of mandibular complete denture.
first set initially made for the patient was remade due to an “unfavorable appearance”. The remade complete dentures were deemed “favorable” by the patient, but were again remade approximately 3 years prior due to her complaint of a “very loose lower denture” and the need for her to use an excessive amount of denture adhesive to retain the mandibular denture. The patient stated she was not satisfied with the third set of dentures, although she had tolerated the “loose fit” for the past 3 years. Observations of the patient’s current dentures revealed fair masticating efficiency, esthetics, and phonetics, a decreased occlusal vertical dimension, and poor retention and stability of the mandibular denture. Clinical and radiographic examination of the patient revealed good neuromuscular skills, normal mandibular movements, a highly resorbed mandibular residual ridge, and normal tongue size with a square tongue form and retruded tongue position (Fig. 3). The patient was advised of the clinical findings and alternative treatment choices, including fabrication of new maxillary and mandibular dentures or implant placement and conversion of her mandibular denture to an overdenture with attachments. The patient opted to have new dentures fabricated, as she did not desire implants placed at this time even though she was told that the lack of retention and stability for the mandibular den-
ture was best approached with an implant-retained overdenture. A fair prognosis for the new dentures was given to the patient due to her highly resorbed mandibular residual ridge and retruded tongue position and the patient’s expectations for greatly improved retention and stability of the new mandibular denture. Fabrication of new maxillary and mandibular complete dentures for the patient proceeded, with special emphasis on retention and stability of the mandibular denture. Border molding of custom impression trays (Triad VLC Denture Base Material; Dentsply Intl, York, Pa) and making of accurate definitive impressions (Impregum; 3M ESPE, St. Paul, Minn) to capture and cover appropriate anatomical features were accomplished to enhance retention of the dentures.1-7 During border molding and making of the mandibular definitive impression, the patient was instructed to pronounce the sound “e”, as in the word “knee”, to aid in positioning the tongue and buccinator muscles to develop a peripheral seal of the mandibular denture borders. Maxillomandibular records and a trial insertion of the dentures were completed at subsequent separate appointments. At each appointment, the patient was reminded of the “challenge” to be accepted to overcome the physical and anatomical features that worked against retention and stability of the mandibular denture.
346
Volume 98 Issue 5
3 Intraoral view of unfavorable retruded tongue position of patient with highly resorbed mandibular residual ridge. Patient complains of nonretentive mandibular complete denture.
4 Intaglio surface of newly fabricated mandibular denture for edentulous patient with highly resorbed mandibular residual ridge and unfavorable tongue position. The patient was repeatedly informed of the important role that tongue position and facial muscles have in improving retention and stability of the new mandibular denture. On several occasions, the patient was instructed to pronounce the sound “e” to help train and coordinate the positions of the tongue and buccinator muscles. At insertion of the new maxillary and mandibular dentures, the patient initially appeared skeptical, but soon acknowledged that through the use of phonetics she was able to improve the retention and stability of her new mandibular complete denture. A clinical remount of the dentures was done to modify and refine the monoplane occlusion. Minimal adjustments of the denture base flanges and intaglio
surfaces were subsequently made to the dentures at 24-hour, 72-hour, 1week, and 2-week postinsertion appointments (Fig. 4). At completion of treatment, the patient acknowledged that she was comfortable and pleased with the fit, retention, function, and esthetics of the new dentures.
DISCUSSION In a study conducted by van Waas, no correlation was found between patient satisfaction with complete dentures and any of the variables concerning the physical condition of the patient’s mouth, including the quality of the mandibular residual ridge.8 He concluded that severe atrophy of the mandibular ridge is not necessarily an
The Journal of Prosthetic Dentistry
indication for preprosthetic surgery or implants. The author reported that many patients in the study with atrophic residual ridges did not have complaints, even with specific problems such as looseness of the mandibular denture. Unfortunately, the patient in this clinical report was dissatisfied and did complain of excessive movement and no retention of her mandibular complete denture. When a dentist provides complete dentures to a patient, he or she must accept the responsibility of educating the patient about their role in a special training program to assist with particular problems with new dentures.9 Stability and retention of a mandibular complete denture may be considered a challenge both to the dentist and the edentulous patient, but the success or failure of the definitive outcome is determined by the patient’s response to the challenge. Several authors have noted that between groups of young and old denture patients, a correlation exists between denture retention and learning processes.10 If a patient can be taught to position the tongue in a purposeful manner to improve retention and stability of a mandibular denture, then the patient may master the challenge and resolve their chief complaint. Constant repetition through the use of coordinated exercises can help a patient learn muscular activity patterns that aid in the retention of a “loose” mandibular denture. Because of the wide range of movements of the mandible, tongue, and facial musculature, the mandibular denture presents the greatest difficulty in learning to use complete dentures.11 Researchers have studied mandibular complete dentures and concluded that muscle activity transcended in importance all other factors responsible for retention, especially in relation to the mandibular denture where the residual ridge is highly resorbed.12 The activity of the lips and cheeks on the labial and buccal surfaces of the mandibular denture, functioning concomitantly with
Bohnenkamp and Garcia
347
November 2007 the delicate lingual tongue contacts, plays an important role in retention. Patients can be taught to pronounce certain phonetic sounds to enable their tongue and buccinator muscles to perform the actual mechanics needed to improve retention and stability of the mandibular denture. As demonstrated by an edentulous patient, the production of the sound “e”, as in the word “knee”, helped to train the patient to use the tongue and buccinator muscles to retain and stabilize a new mandibular denture (Fig. 5). It is important to recognize that coordinated muscle activity was developed with the use of phonetics to teach the patient how to improve the retention of the new mandibular denture.
SUMMARY The ability of an edentulous patient to successfully wear and function with a new mandibular denture can be a frequent complaint that is most often the result of a lack of patient adeptness or unfavorable tongue habits. Some patients have a natural talent in successful use of their mandibular denture; others must learn how to acquire this skill. Patient education relative to phonetics and a favorable tongue position and their role in improving mandibular denture retention should be provided to patients as part of the clinical fabrication and insertion of complete dentures.
5 Edentulous patient pronouncing “e”, as in “knee”, to learn to use tongue and buccinator muscles to retain and stabilize new mandibular complete denture.
REFERENCES 1. Wright CR, Muyskens JJ, Strong LH, Westerman KN, Kingery RH, Williams ST. Study of the tongue and its relation to denture stability. J Am Dent Assoc 1949;39:269-75. 2. Brill N, Tryde G, and Cantor R. The dynamic nature of the lower denture space. J Prosthet Dent 1965;15:401-18. 3. Azzam MK, Yurkstas AA, and Kronman J. The sublingual crescent extension and its relation to the stability and retention of mandibular complete dentures. J Prosthet Dent 1992;67:205-10. 4. Shanahan TE. Stabilizing lower dentures on unfavorable ridges. J Prosthet Dent 1962;12:420-4. 5. Tryde G, Olsson K, Jensen SA, Cantor R, Tarsetano JJ, Brill N. Dynamic impression methods. J Prosthet Dent 1965;15:102334. 6. Lott F, Levin B. Flange technique: an anatomic and physiologic approach to increased retention, function, comfort, and appearance of dentures. J Prosthet Dent 1966;16:394-413. 7. Rahn AO and Heartwell CM. Textbook of Complete Dentures. 5th ed. Baltimore: Wil-
liams & Williams; 1993. p. 121-9. 8. van Waas MA. The influence of clinical variables on patients’ satisfaction with complete dentures. J Prosthet Dent 1990;63:307-10. 9. Bell DH Jr. Prosthodontic failures related to improper patient education and lack of patient acceptance. Dent Clin North Am 1972;16:109-18. 10.Brill N, Tryde G, and Schubeler S. The role of learning in denture retention. J Prosthet Dent 1960;10;468-75. 11.Naylor JG. What the patient should know about complete dentures. J Prosthet Dent 1959;9:832-40. 12.Brill N, Tryde G, and Schubeler S. The role of exteroceptors in denture retention. J Prosthet Dent 1959;9:761-8. Corresponding author: Dr David M. Bohnenkamp Mail Code 7897 7703 Floyd Curl Dr San Antonio, TX 78229 Fax: 210-567-1157 E-mail: [email protected] Copyright © 2007 by the Editorial Council for The Journal of Prosthetic Dentistry.
New Product News The January and July Issues of the Journal carry information regarding new products of interest to prosthodontists. Product information should be sent 1 month prior to ad closing date to: Dr Carol A. Lefebvre, Editor, The Journal of Prosthetic Dentistry, School of Dentistry, AD-2943, Medical College of Georgia, Augusta, GA 30912-1255. Product information may be accepted in whole or in part at the discretion of the Editor and is subject to editing. A black-andwhite glossy photo may be submitted to accompany product information. Information and products reported are based on information provided by the manufacturer. No endorsement is intended or implied by the Editorial Council for The Journal of Prosthetic Dentistry, the Editor, or the publisher.
Bohnenkamp and Garcia