• Journal of Dental Rehabilitation and Applied Science
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• v.31 no.3
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• pp.262-272
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• 2015

Loss of molar support and abnormal jaw relationship lead to occlusal disharmony and cause pathologic signs. Full mouth rehabilitations with reestablishment of occlusal schemes are needed. In this case, the 75 year-old female patient showed posterior bite collapse, irregular occlusal plane and Class II jaw relationship. By observing her profile and interocclusal distance, she was diagnosed as loss of occlusal vertical dimension. Treatment plan is to restore maxillay class I removable partial denture and mandibular fixed prosthesis and to establish vertical dimension and harmonious occlusal plane. Occlusal vertical dimension of 19 mm, which is obtained by 7.5 mm increase between maxillary right lateral incisor and mandibular canine, was established using temporary prosthesis via diagnostic wax-up. Patient adaptation with newly formed vertical dimension was verified during 8 week follow-up period. Within the information of interim prostheses, final restoration was constructed and delivered. The patient showed sound occlusal scheme and esthetic profile.

• The Journal of Advanced Prosthodontics
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• v.11 no.3
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• pp.169-178
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• 2019

PURPOSE. While dental implants have displayed high success rates, poor mechanical fixation is a common complication, and their biomechanical response to occlusal loading remains poorly understood. This study aimed to develop and validate a computational model of a natural first premolar and a dental implant with matching crown morphology, and quantify their mechanical response to loading at the occlusal surface. MATERIALS AND METHODS. A finite-element model of the stomatognathic system comprising the mandible, first premolar and periodontal ligament (PDL) was developed based on a natural human tooth, and a model of a dental implant of identical occlusal geometry was also created. Occlusal loading was simulated using point forces applied at seven landmarks on each crown. Model predictions were validated using strain gauge measurements acquired during loading of matched physical models of the tooth and implant assemblies. RESULTS. For the natural tooth, the maximum vonMises stress (6.4 MPa) and maximal principal strains at the mandible ($1.8m{\varepsilon}$, $-1.7m{\varepsilon}$) were lower than those observed at the prosthetic tooth (12.5 MPa, $3.2m{\varepsilon}$, and $-4.4m{\varepsilon}$, respectively). As occlusal load was applied more bucally relative to the tooth central axis, stress and strain magnitudes increased. CONCLUSION. Occlusal loading of the natural tooth results in lower stress-strain magnitudes in the underlying alveolar bone than those associated with a dental implant of matched occlusal anatomy. The PDL may function to mitigate axial and bending stress intensities resulting from off-centered occlusal loads. The findings may be useful in dental implant design, restoration material selection, and surgical planning.

• Journal of Dental Rehabilitation and Applied Science
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• v.16 no.2
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• pp.149-159
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• 2000

Occlusal disease is comparable to periodontitis in that it is generally not reversible. Occlusal disease, however, like periodontitis, often maintainable. It does itself to treatment and when restorative dentistry is utilized it becomes, in that sense, reversible. Moreover, a systematized and integrated approach will lead to a prognosis that is favorable and predictable. This approach facilitates development of optimum oral function, comfort, and esthetics, resulting in a satisfied patient. Such a systematized approach consists of four logical phase : (1) patient evaluation, (2) comprehensive analysis and treatment planning, (3) integrated and systematic reconstruction, and (4) postoperative maintenance. An integrated treatment plan is first developed on one set of diagnostic casts, properly mounted on a semiadjustable articulator using jaw relationship records. This is accomplished by using wax to make reconstructive modifications to the casts. These modified casts become the blueprint for planned occlusal changes and the fabrication of provisional restorations. The treatment goals are : (1) comfortably functioning temporomandibular joints and stomatognathic musculature, (2) adherence to the basic principle of occlusion advocated by Schuyler, (3) anterior guidance that is in harmony with the envelope of function, (4) restorations that will not violate the patient's neutral zone. This report shows the treatment procedures for a patient whose mandibular position has been altered due to posterior bite collapse. Migration of the maxillary anterior teeth had occurred, and the posterior occlusal contacts showed pathologic interference. Precise diagnosis using mounted casts was executed and prosthodontic reconstruction by the aid of an unconventional orthodontic correction on maxillary flaring was planned. An unconventional orthodontic correction can be accomplished by using preexisting natural teeth, which can be modified for use in active tooth movement or splinted together for orthodontic anchorage. This technique has an advantage over conventional fixed appliance orthodontic therapy because it can accomplish tooth movement concurrently with restorative and periodontal therapy. On occasion, minor tooth movement can be necessary to achieve the optimum occlusal scheme, crown form, and tooth position for the forces of occlusion to be displaced down the long axis of the periodontally compromised teeth. Once the occlusion, periodontal health, and crown contours for the provisional splinted restoration are acceptable, the final splinted restoration can be similarly fabricated, and it becomes an excellent orthodontic retainer.

• The Journal of Advanced Prosthodontics
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• v.2 no.3
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• pp.106-110
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• 2010

The severe wear of anterior teeth facilitates the loss of anterior guidance, which protects the posterior teeth from wear during excursive movement. The collapse of posterior teeth also results in the loss of normal occlusal plane and the reduction of the vertical dimension. This case report describes 77-year-old female, who had the loss of anterior guidance, the severe wear of dentition, and the reduction of the vertical dimension. Occlusal overlay splint was used after the decision of increasing vertical dimension by anatomical landmark, facial and physiologic measurement. Once the compatibility of the new vertical dimension had been confirmed, interim fixed restoration and the permanent reconstruction was initiated. This case reports that a satisfactory clinical result was achieved by restoring the vertical dimension with an improvement in esthetics and function.

• Journal of Dental Rehabilitation and Applied Science
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• v.19 no.1
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• pp.35-41
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• 2003

With the understanding of tooth crown biomechanics and the progress of dentin adhesives, bonded porcelain restorations including a porcelain laminate veneer present an extended spectrum of indications for anterior teeth. Porcelain laminate veneer as a restoration offers the conservative solution that balances the functional and esthetic needs of the anterior dentition. Porcelain's stiffness, its surface characteristics, and the biomechanical strength achieved through bonding to tooth surface enable the restoration of the tooth as a whole supporting occlusal force and masticatory function. Namely, the optical effects inherent in the tooth and the lifelike features of the porcelain make that this restoration approaches the ultimate in esthetic satisfaction for both the dentist and the patient. A 49-year-old female patient with the incisal discoloration of upper central incisors and black triangle between the central incisors was referred to correct her esthetic problems with prosthodontic approach. The patient was satisfied with two porcelain laminate veneers that were made according to prof. Magne and Belser's recommendation.

• Journal of Dental Rehabilitation and Applied Science
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• v.26 no.3
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• pp.241-251
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• 2010

This study aims at contributing to the restorative dentistry by examining results in the vertical load test of four different low invasive fixed partial dentures. Based on a hypothesis on the right upper first molar is missing, three units of FPDs were made for the second premolar and the second molar abutment. that is, twelve metal dies and FPDs were made for resin bonded FPD and Two Key Bridges and Human Bridge without occlusal rest and Human Bridge with occlusal rest. By using universal test machine, the numerical maximum value were recorded during the vertical load test of each FPDs after the bonding process treated by Maxcem which is resin cement. The failure process and its result of prosthesis were also observed. The maximum load was 7,295 N, 4,729 N, 2,190 N, 3,073 N from groups of resin bonded FPD, Two Key Bridge, Human Bridge without occlusal rest and Human Bridge with occlusal rest respectively. There was a statistical significance among the groups of resin bonded FPD, Two Key Bridge and Human Brides. However, there was no significant difference between Human Bridge without occlusal rest and Human Bridge with occlusal rest. Regarding the failure of prosthesis, the groups of Resin Bonded FPD and Two Key Bridge showed that one of the abutment teeth in the both side of retention part was highly failed earlier than the other one (83.2% and 66.6% respectively). While, Human Bridge without occlusal rest and Human Bridge with occlusal rest showed high percentage of failure in the abutment teeth in the both side of retention part at the same time (91.6% and 58.3% respectively). This study demonstrates that the group of Human Bridges has low resistance to the vertical loads of low invasive FPDs in comparison with the groups of resin bonded FPD and Two Key Bridge. Nevertheless, the maximum occlusal load of the restorative position, resistance to diverse restoration failure, amount of tooth reduction and patients' cooperation should be considered when they are applied in the clinic in order to choose an appropriate restoration for each patient.

• The Journal of Korean Academy of Prosthodontics
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• v.58 no.4
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• pp.369-377
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• 2020

Gradual teeth wear is normal physiological progress, severe tooth wear can causes dysfunction, occlusal plane disharmony and esthetic problems. If additional space is needed for prosthetic restoration due to severe attrition, full mouth rehabilitation with increase of occlusal vertical dimension may be considered. In this case, 72 year old male patient with severe worn dentition, irregular gingival zenith and deep anterior bite was treated by full mouth rehabilitation for regaining the space for restoration, improving relationship and esthetic of anterior teeth. Provisional restoration obtained by systemic analysis, diagnosis and re-evaluation for a sufficient time was replicated to final restorations through double scanning technique using monolithic zirconia blocks. Satisfactory functional and esthetic outcomes were obtained.

• Journal of Dental Rehabilitation and Applied Science
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• v.38 no.1
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• pp.60-68
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• 2022

A patient with severe periodontitis has causative factors that cause pathological tooth movement, the occlusion is disintegrated, and the vicious cycle of worsening periodontitis is repeated. In particular, when pathological tooth movement occurs in the maxillary anterior region, the patient has an aesthetic sense of atrophy, and the quality of life was reduced. Therefore, when orthodontic treatment was added to patients with severe periodontitis, it promotes the formation of new bone, reduces periodontal cysts, and obtains clinical attachment, which leads to favorable results in prosthetic restoration, thereby enabling ideal occlusion, function and aesthetics. Periodontal treatment, orthodontic treatment, natural tooth restoration, and implant prosthesis were planned for patients with pathological tooth movement in the anterior region due to loss of occlusal support in the posterior region. As a result, an ideal restoration space was secured, a stable restoration of occlusal contact was formed, and the maxillary anterior teeth were aesthetically improved.

• Journal of Dental Rehabilitation and Applied Science
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• v.20 no.2
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• pp.121-134
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• 2004

This article describes a clinical protocol for the conventional rehabilitation of patient diagnosed with partial anodontia. A combined dental therapy approach was used and included endodontic therapy and root capping on the maxillary central incisors, fabrication of a maxillary overdenture, and fabrication of mandibular konus overdenture supported by 3 konus abutments. Within this protocol, tooth-supported overdenture prostheses are used for 2 purposes: first, to obtain the most rigid retention and function at an established maxillary-mandibular relationship; and second, to continuously maintain function and esthetic appearance applying immediate dentures after teeth extraction. The idea behind this protocol and its associated clinical procedures is presented along with a discussion compared with implant therapy. In the case introduced, and after 7 years of observation, the therapy can be seen as a success. We increased the occlusal vertical height in this case, but it would be more appropriate to see this as recovering the occlusal vertical height that was lost. The process of increasing the occlusal vertical height, that is restoration of the face, modification of the extrinsic occlusion of the incisors, and retraction of the mandible is very difficult and important. Ultimately, class III malocclusion is fixed, adequate occlusal vertical height is gained, and the retracted posterior anodontial portion is restored by prosthodontic dentures based on the rigid support theory. The result of the therapy done on the later-achieved malocclusion with partial anodontia on the posterior portion must consider the following in order to maintain the safety of the esthetics of the tooth and face for a period of time: 1) occlusal restoration with an ideal occlusal vertical height, 2) allowance of the final occlusion induced by the functional relationship of the upper and lower jaw, 3)final occlusion functionally induced by the lip competence limit.

• The Journal of Korean Academy of Prosthodontics
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• v.57 no.4
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• pp.405-415
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• 2019

Excessive tooth wear can cause irreversible damage to the occlusal surface and can alter the anterior occlusal relationship by destroying the structure of the anterior teeth needed for esthetics and proper anterior guidance. The anterior deep bite is not a morbid occlusion by itself, but it may cause problems such as soft tissue trauma, opposing tooth eruption, tooth wear, and occlusal trauma if there are no stable occlusal contacts between the lower incisal edge against its upper lingual surface. The most important goal of treatment is to form stable occlusal contact in centric relation. In this case report, patients with decrease in vertical dimension and anterior deep bite due to maxillary posterior tooth loss and excessive tooth wear were treated full mouth rehabilitation with increased vertical dimension to regain the space for restoration and improve anterior occlusal relationship and esthetics. The functional and aesthetic problems of the patient could be solved by the equal intensity contact of all the teeth in centic relation (CR), anterior guidance in harmony with the functional movement, and restoration of the wear surface beyond the enamel range.