Biotechnology ; Diffusion of Innovation ; Humans ; Inventions

Dental Alloys ; Dental Implants ; Dental Materials ; Dental Prosthesis Design ; trends ; Humans ; Zirconium

OBJECTIVETo investigate the occlusal force in the position of maximum intercuspation in the population with individual normal occlusion using a new occlusal analyzing equipment (TeeTester).

METHODSTwenty-nine volunteers aged from 21 to 32 years were recruited. Occlusal analysis was performed using TeeTester. An arch model of each subject was retrieved in order to measure the tooth width and to calculate the force applied on each tooth.

RESULTSThe occlusal force in the position of maximum intercuspation was (900 ± 361) N (range: 335-1 727 N). The maximum occlusal force was correlated with the contacting area. The mean value of occlusal force on the molars ranged from 107 to 156 N, with the mean value on the first molar greater than that on the second molar within the same quadrant. The mean value of occlusal force ranged from 39 to 66 N on the premolars, and from 11 to 33 N on the front teeth.

CONCLUSIONSThere is a great variation of occlusal force in maximum intercuspation in individual normal occlusion. TeeTester occlusal analyzing system provides absolute occlusal force in kilogram and can be cowerted to N, which may assist clinical examination in patients.

Adult ; Bicuspid ; Bite Force ; Cross-Sectional Studies ; Dental Occlusion ; Humans ; Incisor ; Malocclusion ; Molar

OBJECTIVETo evaluate the 10-year clinical results of implant prostheses in edentulous patients.

METHODSBetween August 1994 and November 2009, 762 implants were placed in 127 patients (162 jaws) with the mean age of (56.0 ± 10.9) years in Peking University, School and Hospital of Stomatology. Sinus lift, guide bone regeneration (GBR) and onlay graft were used according to the indications of bone defect types. Overdentures and fixed bridges were delivered.Overdentures were retained/supported by ball, magnet, telescopic crown or milled bar. Clinical evaluation included peri-implant soft tissue health status, prostheses functional status and complications.Radiographic evaluations were conducted at operation day, 3 months post-operatively, right after prostheses delivery, and annually afterwards. Clinical data were collected and analyzed.

RESULTSOf the 127 patients, 116 were edentulous mandible and 46 edentulous maxilla, with a mean follow-up period 109.2 months(45-228 months). Thirteen implants were lost and the 10-year implant cumulative survival rate was 97.8% and the prostheses success rate was 100.0%. The prevalence of peri-implantitis was 3.8% (29/762). Sixty-seven point nine percent of the patients underwent implant placement without bone graft.Sinus lift technique and guided bone regeneration technique were the most often used with 84.8% (39/46) in the upper jaws and 6.2% (10/162) in the total jaws respectively. Seventy-one percent of the cases(115/162) was overdentures. Telescopic, milled-bar, and magnetic retained/supported overdentures were the most commonly used with 34.8% (40/115) , 27.0% (31/115) , and 20.0% (23/115) respectively. The implant-supported fixed prostheses included adhesive retained fixed bridges and screw retained fixed bridges with the ratio of 19.1% and 80.9% respectively. The prevalence of 10-year post-prosthodontic complications was 53.5% (68 cases). The most common complications were prosthetic and uperstructure complications.

CONCLUSIONSThe 10-year implant-retained/supported prostheses was a successful modality in edentulous cases.Sinus lift technique and guided bone regeneration technique are the most commonly used techniques with predictable clinical results. Telescopic crowns milled bar and magnet with 4-6 implants retained/supported overdenture were the most often used retention systems and telescopic crown overdenture had more advantages in terms of long-term maintenance and satisfaction.

Crowns ; Dental Implants ; Dental Prosthesis Design ; Dental Prosthesis, Implant-Supported ; Denture, Overlay ; Humans ; Jaw, Edentulous ; Maxilla ; Mouth, Edentulous ; Peri-Implantitis ; Retrospective Studies

OBJECTIVETo investigate the effect of ridge preservation with Bio-Oss Collagen and Bio-Gide in posterior sites.

METHODSFrom May 2010 to July 2013, 16 patients with bilateral posterior teeth planned to be extracted and replaced by implants were enrolled. One of the sockets was randomly selected and presserved with Bio-Oss Collagen and Bio-Gide (intervention group). The contralateral socket was left to heal spontaneously (control group). Cone-beam (CBCT) scans were performed immediately after the extraction and 6 month later. The bone cores were collected during the implant placement surgery and analyzed by micro-computed tomography.

RESULTSAfter 6 month healing, the vertical and horizontal dimensional alteration of the treatment group were (0.55 ± 1.05) mm and (-0.99 ± 0.94) mm respectively, while the vertical and horizontal change of control group were (-0.71 ± 1.41) mm and (-2.26 ± 1.29) mm respectively. The micro-computed tomography results showed that there was no significant difference in new bone volume between control and intervention groups.

CONCLUSIONSApplying Bio-Oss Collagen and Bio-Gide for ridge preservation in posterior sites resulted in less vertical and horizontal bone resorption of sockets following extraction.

Alveolar Process ; diagnostic imaging ; Biocompatible Materials ; therapeutic use ; Bone Resorption ; prevention & control ; Collagen ; therapeutic use ; Heterografts ; Humans ; Minerals ; therapeutic use ; Organ Sparing Treatments ; methods ; Tooth Extraction ; Wound Healing ; X-Ray Microtomography

OBJECTIVETo evaluate the clinical outcome of maxillary sinus augmentation and implant placement following removal of a maxillary antral cyst.

METHODSIn this study 32 patients with 33 maxillary antral cysts were enrolled. The partial wall of cyst was removed through a small lateral sinus approach and cyst spontaneous shrink was expected when wall of cyst was destroyed for open drainage. Three to six months later the secondary sinus approach 1.5 mm circling the first approach for augmentation was undertaken. Dental implants were placed simultaneously or later. All patients finished prosthetic rehabilitation in the study and were followed up for (30.9 ± 11.5) months. The intraoperative and postoperative complications were recorded. The survival rate of the implants was calculated.

RESULTSIn this study, 33 maxillary antral cysts of 32 patients were removed. Maxillary sinus augmentation was performed after a mean of (4.5 ± 1.5) months (range, 2-8 months). Sixty-two implants were inserted and all patients finished prosthetic rehabilitation after a mean of (10.8 ± 2.7) months (range, 5-17 months). The survival rate of implants was 95% (59/62). Three implants failed before their prosthesis delivered due to failure of osseointegration and were reinserted later. No recurrence of cyst was observed until the last recall. In this study, 24 specimens were mucosal cysts. Five specimens were mucoceles and 4 specimens were not certain in pathology.

CONCLUSIONSMaxillary sinus cysts have a negative effect on maxillary sinus augumentation if not removed. The present preliminary data of the study suggests that the clinical result of maxillary sinus augmentation and implant placement following removal of a maxillary antral cyst is predictable.

Cysts ; surgery ; Dental Implantation, Endosseous ; methods ; Dental Implants ; Dental Restoration Failure ; Follow-Up Studies ; Humans ; Maxillary Sinus ; surgery ; Neoplasm Recurrence, Local ; Osseointegration ; Osteogenesis ; Paranasal Sinus Diseases ; surgery ; Sinus Floor Augmentation ; methods ; Time Factors ; Treatment Outcome