BACKGROUND: In order to restore severely attrited teeth properly, surgical intervention in the form of a crown-lengthening procedure may be required. And also, proper diagnosis and treatment sequencing is critical to obtain a successful results. Adequate diagnostic wax-up ensures good esthetics and healthy periodontal tissue. CASE DESCRIPTION: This clinical case report describes a diagnostically based protocol for restoration on mandibular anterior teeth with crown lengthening procedure and the treatment of partially edentulous mandible combined with an edentulous maxilla. In addition, the effort to prevent the combination syndrome was described. CLINICAL IMPLICATION: An interdisciplinary diagnosis and examination through visualization of the desired results ensure conservative and more predictable outcome.
Crown Lengthening ; Crowns ; Dietary Sucrose ; Esthetics ; Humans ; Mandible ; Maxilla ; Mouth ; Mouth Rehabilitation ; Tooth

BACKGROUND: Though implant dentistry is very successful and predictable in treatment of patients with destroyed dentition, there are some cases with limitations to implant therapy. In these cases, alternative treatment modality should be considered. CASE DESCRIPTION: A patient with destroyed dentition was rehabilitated with a lateral rotational path removable partial denture. According to the diagnosis, we determined to raise vertical dimension for esthetic and functional restoration. The final restoration was performed after four months of provisional period. CLINICAL IMPLICATION: The edentulous patients with compromised esthetics and functions can be successfully treated with a rotational path removable partial denture through adequate treatment planning and precise laboratory procedure.
Dentistry ; Dentition ; Denture, Partial, Removable ; Esthetics ; Humans ; Mouth ; Mouth Rehabilitation ; Tooth Attrition ; Vertical Dimension

STATEMENT OF PROBLEM: The aim of this study was to study the effects of various surface treatments to a titanium surface on the expression of Runx2 in vitro. MATERIAL AND METHODS: Human Osteosarcoma TE-85 cells were cultured on machined, sandblasted, or anodic oxidized cpTi discs. At various times of incubation, the cells were collected and then processed for the analysis of mRNA expression of Runx2 using reverse transcription-PCR. RESULTS: The expression pattern of Runx2 mRNA was differed according to the types of surface treatment. When the cells were cultured on the untreated control culture plates, the gene expression of Runx2 was not increased during the experiments. In the case of that the cells were cultured on the machined cpTI discs, the expression level was intermediate at the first day, but increased constitutively to day 5. In cells on sandblasted cpTi discs, the expression level was highest in the first day sample and the level was maintained to 5 days. In cells on anodized cpTi discs, the expression level increased rapidly to 3 days, but decreased slightly in the 5-th day sample. CONCLUSION: Different surface treatments may contribute to the regulation of osteoblast function by influencing the level of gene expression of key osteogenic factors.
Durapatite ; Gene Expression ; Humans ; Osteoblasts ; Osteogenesis ; Osteosarcoma ; RNA, Messenger ; Titanium

Mandible fractures belong to the most common fractures encountered in maxillofacial trauma. Because mandible is such a unique structure with hinge joint and masticatory muscles attached to the body of mandible, attention must be paid to avoid displacement during treatment. Displacement during fracture reduction leads to malocclusion. Many TMJs function with complete comfort and apparent normalcy in adapted centric posture, even though they have undergone deformation caused by trauma. This clinical report describes the patient with post traumatic malocclusion and its prosthetic treatment. His fractured mandible was openly reduced in changed position, as a result his occlusion has been changed. He was treated by prosthetic method in so-called adapted centric posture.
Displacement (Psychology) ; Humans ; Joints ; Malocclusion ; Mandible ; Masticatory Muscles ; Posture ; Temporomandibular Joint

Surgical management of oral cancer results in compromised masticatory and swallowing function which affects patient in social and psychological aspects due to reduced phonetic ability and facial deformity, thus, it is imperative to provide applicable prosthetic treatment to overcome such complications. This clinical study describes rehabilitation of a patient with squamous cell carcinoma treated with marginal mandibulectomy and implantation on preserved posterior portion of mandible to provide stability and support for subsequent denture treatment. Kennedy class IV removable partial denture has provided satisfactory results in esthetics and function. Bone level stability around implants was reported to be maintained during eight months of clinical observation.
Carcinoma, Squamous Cell ; Congenital Abnormalities ; Deglutition ; Denture, Partial, Removable* ; Dentures ; Esthetics ; Humans ; Mandible ; Mouth Neoplasms ; Rehabilitation*

STATEMENT OF PROBLEM: Changes of the marginal bone around dental implants have significance not only for the functional maintenance but also for the esthetic success of the implant. It was proposed that bone-retention elements such as microthreads at the coronal part of implant might help maintain the marginal bone level. PURPOSE: This study was designed to evaluate the effect of microthread configuration within the marginal coronal portion of the implant fixture at the marginal bone changes after loading around two different external hex implants. MATERIAL AND METHODS: Twenty-four patients were included and randomly assigned to treatment with Branemark system implants (Group 1, rough-surfaced implants, n=20) and Oneplant system implants (Group 2, rough-surfaced neck with microthreads, n=20). Clinical and radiographic examinations were conducted at baseline (implant loading) and 1 year postloading. Data analysis was performed by the SAS statistical package version 9.1.3 (SAS Institute, Cary, NC, USA) and the final model was calculated by the MIXED procedure (three-level ANCOVA) for marginal bone change of each test group at baseline and 1 year follow-up. RESULTS: Comparing to baseline, significant differences were noted in marginal bone level changes for the 2 groups at 1 year follow-up (P<0.05). Group 1 had a mean crestal bone level changes of 0.83+/-0.31mm; Group 2 had a mean crestal bone level changes of 0.44+/-0.36mm. Rough-surfaced with microthreads implants showed significantly less marginal bone loss than rough surfaced neck without microthread implants. CONCLUSION: A rough surface with microthreads at the implant was beneficial design to maintain the marginal bone level against functional loading.
Bone Resorption ; Dental Implants ; Follow-Up Studies ; Humans ; Neck ; Phenothiazines ; Statistics as Topic

STATEMENT OF PROBLEM: Over the past two decades, implant supported fixed prosthesis have been widely used. However, there are few studies conducted systematically and intensively on the splinting effect of implant systems in mandible. PURPOSE: The purpose of this study was to investigate the changes in stress distributions in the mandibular implants with splinting or nonsplinting crowns by performing finite element analysis. MATERIALS AND METHODS: Cortical and cancellous bone were modeled as homogeneous, transversely isotropic, linearly elastic. Perfect bonding was assumed at all interfaces. Implant models were classified as follows. Group 1: Branemark length 8.5mm 13mm splinting type Group 2: Branemark length 8.5mm 13mm Nonsplinting type Group 3: ITI length 8.5mm 13mm splinting type Group 4: ITI length 8.5mm 13mm Non-splinting type An load of 100N was applied vertically and horizontally. Stress levels were calculated using von Mises stresses values. RESULTS: 1. The stress distribution and maximum von Mises stress of two-length implants (8.5mm, 13mm) was similar. 2. The stress of vertical load concentrated on mesial side of implant while the stress of horizontal load was distributed on both side of implant. 3. Stress of internal connection type was spreading through abutment screw but the stress of external connection type was concentrated on cortical bone level. 4. Degree of stress reduction was higher in the external connection type than in the internal connection type.
Crowns ; Finite Element Analysis ; Mandible ; Prostheses and Implants ; Splints

STATEMENTS OF THE PROBLEM: Over the past decades, conventional complete dentures were used for various patients although they have incomplete function. Overdentures using dental implants could help the improvement of denture function. PURPOSE: The purpose of this study was to compare the strains of abutment and bone on implant overdenture between splinted and unsplinted type of prosthesis. Additionally, the strain values of parallel placed implant model and unparallel placed implant model were compared. MATERIAL AND METHODS: Two acrylic resin model were prepared and two implants were placed at the canine positions in each model. In the first model, two implant were placed parallel. In the second model, two implants were placed with 10 degree labiolingual divergence. Two types of abutment were connected to the fixtures alternatively. One was splint type of Hader bar, the other was unsplint type of ball abutment. Overdentures were fabricated with corresponding attachment systems and seated on abutments. Strains of abutments and labial bone simulants were measured with electric resistance strain gauges when static load from 100 N to 200 N were applied to overdentures. RESULTS: 1. Splinted type of overdentures using bar and clip showed higher absolute strain values. But the strain was compressive and the load was shared by two implants (P < .05). 2. Unsplinted type overdentures using ball and O-ring showed low absolute strain values (P < .05). 3. Labially inclined implant showed higher tensile strain values in unsplinted type of prosthesis than in splinted type of prosthesis. Lingually inclined implant showed rather low strain values under load (P < .05). 4. Non parallel implant model showed higher absolute strain values than parallel placed implant model comprehensively (P < .05).
Dental Implants ; Denture, Complete ; Denture, Overlay ; Dentures ; Electric Impedance ; Humans ; Prostheses and Implants ; Splints ; Sprains and Strains

STATEMENT OF PROBLEM: Unreasonable distal cantilevered implant-supported prosthesis can mask functional problems of reconstruction temporarily, but it can cause serious strain and stress around its supported implant and surrounding alveolar bone. PURPOSE: The purpose of this study was to evaluate strain of implants supporting distal cantilevered fixed prosthesis with two different cantilevered length under distal cantilevered static load. MATERIAL AND METHODS: A partially edentulous mandibular test model was fabricated with auto-polymerizing resin (POLYUROCK; Metalor technologies, Stuttgart, Swiss) and artificial denture teeth (Endura; Shofu inc., Kyoto, Japan). Two implants-supported 5-unit screwretained cantilevered fixed prosthesis was made using standard methods with Type III gold alloy (Harmony C & B55; Ivoclar-vivadent, Liechtenstein, Germany) for superstructure and reinforced hard resin (Tescera; Ivoclar-vivadent, Liechtenstein, Germany) for occlusal material. Two strain gauges (KFG-1-120-C1-11L1M2R; KYOWA electronic instruments, Tokyo, Japan) were then attached to the mesial and the distal surface of each standard abutment with adhesive (M-bond 200; Tokuyama, Tokyo, Japan). Total four strain gauges were attached to test model and connected to dynamic signal conditioning strain amplifier (CTA1000; Curiotech inc., Paju, Korea). The stepped 20-100 N in 25 N increments, cantilevered static load 8mm apart (Group I) or 16mm apart (Group II), were applied using digital push-pull gauge (Push-Pull Scale & Digital Force Gauge, Axis inc., Seoul, Korea). Each step was performed ten times and every strain signal was monitored and recorded. RESULTS: In case of Group I, the strain values were surveyed by 80.7 ~ 353.8 micrometer/m in Ch1, 7.5 ~ 47.9 micrometer/m in Ch2, 45.7 ~ 278.6 micrometer/m in Ch3 and -212.2 ~ -718.7 micrometer/m in Ch4 depending on increasing cantilevered static load. On the other hand, the strain values of Group II were surveyed by 149.9 ~ 612.8 micrometer/m in Ch1, 26.0 ~ 168.5 micrometer/m in Ch2, 114.3 ~ 632.3 micrometer/m in Ch3, and -323.2 ~ -894.7 micrometer/m in Ch4. CONCLUSION: A comparative statistical analysis using paired sample t-test about Group I Vs Group II under distal cantilevered load shows that there are statistical significant differences for all 4 channels (P<0.05).
Adhesives ; Alloys ; Axis, Cervical Vertebra ; Dentures ; Hand ; Liechtenstein ; Masks ; Prostheses and Implants* ; Seoul ; Tooth

PURPOSE: The purpose of present study is to examine the correlation between the accuracy of abutment preparation and the marginal adaptation of metal coping. With this view, this study compared the correlations regard to the three different manufacturing methods of selective laser sintering technique, milling and casting. MATERIALS AND METHODS: Two master models were made in a different way. First model with deep chamfer margin was prepared directly by a general clinician and the second model was designed by 3-D designing software program with the same abutment preparation principle and produced by computer aided manufacturing. 12 Co-Cr alloy copings were produced respectively with three different method; SLS system, CAD/CAM milling and conventional lost wax technique from each master model. The total 72 copings fully sit on the master model were stereoscopically evaluated at 40 points along the entire circumferential margin. RESULTS: Significant differences in the absolute marginal discrepancies of Co-Cr copings from SLS system (P=.0231) and casting method (P<.0001) were shown between hand preparation model and computer designed model. However, no significant difference was found between the two model groups from milling method (P=.9962). CONCLUSION: Within the limitation of this study, the effect of the accuracy of abutment preparation on the marginal adaptation of Co-Cr coping is statistically significant in SLS system and casting group. The copings produced by SLS system exhibited the lowest marginal discrepancies among all groups, and the marginal gap of this method group was influenced by the accuracy of the abutment preparation.
Alloys* ; Computer-Aided Design ; Dental Abutments ; Hand ; Tooth Preparation* ; Tooth*