OBJECTIVETo observe the restoration effect of anterior all zirconia ceramic resin bonded fixed partial dentures, and to find a new fixed restorative method for restoring one or two missing anterior teeth.

METHODSTwenty-nine missing anterior teeth from twenty-three patients were restored with all zirconia ceramic resin bonded fixed partial dentures, and restorations were devided in to two groups according to the number of retainers, i.e. the single-retainer group and the two-retainer group. The integrity, secondary caries, marginal shade and color match of the restorations were evaluated with the standard of American Public Health Association (APHA). The average period of observation was 22 months.

RESULTSOne restoration from the two-retainer group failed, two restorations from the single-retainer group failed. The shade of two restorations were evaluated as discernable whiter compared to adjacent teeth. There was no secondary caries and marginal shade. The two year success rate of anterior all zirconia ceramic resin bonded fixed partial dentures was 90% (26/29).

CONCLUSIONSAll zirconia ceramic resin bonded fixed partial dentures used for less than two anterior missing teeth can achieved definite aesthetic effect and physiologic function. It was a new type of fixed restoration for anterior missing teeth. However, to determine long-term result of this restoration more data are needed.

Adult ; Aged ; Cementation ; Ceramics ; chemistry ; Dental Restoration Failure ; Denture, Partial, Fixed, Resin-Bonded ; Female ; Follow-Up Studies ; Humans ; Incisor ; Male ; Middle Aged ; Tooth Loss ; therapy ; Young Adult ; Zirconium ; chemistry

OBJECTIVETo analyze stress distribution of two framework designs in compound galvano-ceramic bridges made with three-dimensional finite element models.

METHODSThree-dimensional finite element models were developed for compound galvano-ceramic bridges with two designed retainers of Ni-Cr frameworks which ringed or partially covered the electroformed gold caps. The models were vertically loaded 200 N on the center of the occlusal surface of the pontic and loaded 400 N on the center of buccoclusal marginal ridge from buccal aspect to lingual aspect at a 30 degree angle with the occlusion plane respectively. The stress distributions and the level of stress concentration in the two models were analyzed by the FEA software.

RESULTSStress distributing in two designed framework of compound galvano-ceramic bridges were similar. The highest von Mises stress of compound galvano-ceramic bridges was concentrated in the distal connector of the pontic and retainer. Under the vertical loading, the von Mises stress was 24.17 MPa for the partial cover retainer of the Ni-Cr framework and 24.85 MPa for the circular retainer. Under the lateral loading, the corresponding figures were 42.83 MPa and 42.69 MPa. No matter vertical or lateral loading, the margin of electroformed cap was the concentration area of the von Miese stress.

CONCLUSIONSIn this study, the stress concentration area of compound galvano-ceramic bridges with Ni-Cr framework and electroformed gold caps was the connector and the margin of electroformed cap was the insubstantial area.

Dental Prosthesis Design ; Denture, Partial, Fixed ; Finite Element Analysis ; Metal Ceramic Alloys ; Stress, Mechanical

To explore the diagnostic value of 75 commonly used clinical laboratory markers for differentiation of traditional Chinese medicine syndromes such as liver and gallbladder damp-heat and liver depression and spleen deficiency in patients with chronic hepatitis B.

OBJECTIVETo evaluate and compare effects of compound galvano-ceramic bridges with Ni-Cr alloy ceramic bridges and gold alloy ceramic bridges in clinic.

METHODSA total of 105 bridges were made for 103 patients. Of them, 35 were compound galvano-ceramic bridges, 35 Ni-Cr alloy ceramic bridges, and 35 gold alloy ceramic bridges respectively. The marginal fitness and fracture of ceramic bridges were checked and caries or second caries of all abutments were also examined in clinic at 6 years after cementation.

RESULTSThe marginal fitness of compound galvano-ceramic bridges was evaluated as good in 100% of the bridges, which was better than the fitness of gold alloy ceramic bridges (91%) and Ni-Cr alloy ceramic bridges (77%) (P < 0.01). There was no difference in fracture of ceramic layer among compound galvano-ceramic, gold alloy ceramic, and Ni-Cr alloy ceramic bridges at 6 years (P > 0.05). None of compound galvano-ceramic bridge was found out caries or second caries of abutments. Two of 35 (6%) gold alloy ceramic bridges was found out second caries of abutments and five of 35 (14%) Ni-Cr alloy ceramic bridges were found out caries or second caries of abutments at 6 years. None of frameworks of all bridges was loose or broken.

CONCLUSIONSThe 6-year clinical study on compound galvano-ceramic bridges presents good results in marginal fitness and fracture resistance, which indicates the compound galvano-ceramic bridge can be used in clinic.

Adolescent ; Adult ; Dental Casting Technique ; Denture, Partial, Fixed ; Female ; Gold Alloys ; Humans ; Male ; Metal Ceramic Alloys ; Middle Aged ; Young Adult

Objective To explore the clinical effect of direct posterior restoration and screw-rod (plate) internal fixation technique for the treatment of children with congenital atlantoaxial subluxation.Methods Seven children with congenital atlantoaxial subluxation,admitted to our hospital from April 2008 to March 2011, were chosen in our study; and 3 of them were combined with tonsil hernia of cerebellum and 3 with occipitalization. Japanese Orthopedic Association (JOA) scale was used to evaluate the patient's condition. Five patients were treated by internal fixation with occipital bone screw-axis (C2) pedicle screw and 2 were with atlas C1-C2.Articulatio atlantoepistrophica repositioning was performed during the operation. The post-operative improvement degree and therapeutic effect of these patients were assessed based on the JOA scores and imaging. Results All the patients were followed up for 1-15 months (average 3.2 months). The clinical symptoms of all patients improved significantly. The positions of all screws were fine 1 month after operation. Three-dimensional CT showed that occipital/interbody fusions were good in 3 patients.JOA scores after the surgery were 7-16 with an average scores of (12.03±3.58),which were significantly different as compared with those before the surgery ([7.56±3.16], P＜0.05). Conclusion Direct posterior restoration and internal fixation technique is a safe and effective method for the treatment of children with congenital atlantoaxial subluxation.

Objective o investigate the clinical characteristics of middle cranial fossa arachnoid cyst (MCFAC) and its therapeutic effects with different surgical methods. Methods Three hundred and fifty-two patients with MCFAC (about 2.58% of patients with intracranial space occupying lesion),admitted to our hospital from May 2001 to May 2008, were chosen in out study; their clinical data,surgical approach and prognosis were analyzed retrospectively. The gender ratio of patient with MCFAC adopted resection of arachnoid cyst and arachnoid cyst-peritoneal shunt was performed in 28 patients.Results Follow-up was performed for 3 months to 3 years. The headache completely disappeared in 75 patients (58.59%) and partial remission in 41 (32.03%) after the operation. The frequency and degree of seizures obviously decreased in 8 of the patients with MCFIAC. Eleven patients with dystropy,attention-deficit disorder or difficulty of learning got improvement. The head circumference and local skull eminentia was stable. The cyst disappeared completely in 46 patients (13.07%), partially in 257 (73.01%) and no changes in 49 (13.92%). Conclusion The clinical features of MCFAC is that it mainly occur in the left side of male. The younger the patient with MCFAC is, the better the treatment effect in the surgical intervention is. good outcome can be achieved by resection of the parietal layer of arachnoid cysts. The indication of shunt with meso-low pressure shunt system is for larger arachnoid cyst.

OBJECTIVE: To evaluate the effect of computer aided design and computer aided manufacture (CAD/CAM) one-piece zirconia posts and cores for the restoration of defective teeth. METHODS: In the study, 72 defective teeth of 47 patients who had proper root canal therapy were restored with CAD/CAM one-piece zirconia posts and cores. All the ceramic crowns were finally used to restore contour and function of the teeth. The defective teeth were divided into two groups on the basis of the teeth defect degree. Group A: 39 defective teeth presented with three or four coronal residual walls, and group B: 33 defective teeth presented with less than two coronal residual walls. During the clinical observation period, the stability, dislocation of posts and the occurrence of fractures in either teeth or posts and cores were assessed and analyzed with a paired t test(α=0.05). Meanwhile shade matching was conducted between the restored teeth and normal reference teeth, the marginal fitness of the restored teeth were recorded according to the standard of United States Public Health Service (USPHS) and analyzed with descriptive statistics. RESULTS: The average follow up was (65.0±4.8) months. During the observation period, the restorations were examined both clinically and with periapical radiograph. No incidence of teeth fracture or posts and cores complications were observed in both groups, and all CAD/CAM one-piece zirconia posts and cores remained intact with restored teeth. There were no post and core dislodgement or fracture. There was no difference between group A and group B (P>0.05). The restorative effect of CAD/CAM one-piece zirconia posts and cores with all the ceramic crowns were assessed according to the standard of USPHS, and the number of the restored tooth shade matching with level A was 67, and 5 with level B. The rate of shade matching was 93.06%. As the marginal fitness, 64 restored teeth were level A, and 8 with level B. The rate of restorative teeth marginal fitness was 88.89%. CONCLUSION CAD/CAM one-piece zirconia posts and cores were successfully used to restore defective teeth and received excellent clinical effect. So, it can be a good choice for defective teeth which need post-cores and crowns restoration.
Computer-Aided Design ; Dental Prosthesis Design ; Dental Restoration Failure ; Follow-Up Studies ; Humans ; Incisor ; Post and Core Technique/instrumentation* ; Prospective Studies ; Tooth Fractures ; Zirconium

Animals ; Chelating Agents ; pharmacology ; Lead ; toxicity ; Learning ; drug effects ; Memory Disorders ; drug therapy ; Mice ; Morus ; chemistry ; Plant Extracts ; chemistry ; pharmacology ; Random Allocation ; Succimer ; pharmacology

OBJECTIVE: To verify the consistency between the digital manufacturing simple intraoral Gothic arch-tracing device and the traditional intraoral Gothic arch-tracing device in determining the centric relation of complete dentures restoration. METHODS: Ten outpatients with edentulous jaws were selec-ted, and the centric relation of the patients was determined by digital manufacturing of simple intraoral Gothic arch-tracing device (T1) and traditional intraoral Gothic arch-tracing device (T2); the difference of clinical operation time between the two methods was recorded; the upper and lower edentulous jaw plaster models were scanned with two kinds of centric relation, the Standard Triangle Language (STL) files imported into Geomagic studio software to apply the best fitting of multiple points of the both upper jaw models, the fitted STL files imported into the 3 shape viewer software, and the maximum position deviations of the vertical, labial (buccal) and lingual directions of the mandibular midline area and molar areas in T1 and T2 groups measured. During the clinical complete dentures try-in, we observed whether there was midline deviation in the mouth of T1 group and T2 group, and whether the occlusion of posterior teeth was stable or not. RESULTS: The mean time spent on determining the centric relation of T1 and T2 groups was (41.90±2.64) min, (57.50±2.37) min respectively. Paired t test was conducted in the two groups, P < 0.01 with significant statistical difference; The mean maximum position deviation between T1 group and T2 group of the midline mandibular region in labial lingual direction was (0.32±0.14) mm, that was (0.40±0.23) mm in vertical direction; the mean maximum position deviation of molar area in buccal lingual direction was (0.35±0.23) mm and that was (0.33±0.20) mm in vertical direction. In the vertical and horizontal directions, the maximum position deviation of mandibles between group T1 and group T2 was controlled within 0.5 mm. In the process of clinical complete dentures try-in, there was no deviation from the center line of dentures. There was not warping, swinging and other poor stability phenomena in T1 and T2 groups. CONCLUSION The digital manufacturing of simple intraoral Gothic arch-tracing device can be used to determine the centric relation of complete dentures, which can not only save time of clinical operation, but also ensure the accuracy of the centric relation.
Humans ; Centric Relation ; Jaw Relation Record/methods* ; Denture, Complete ; Mouth, Edentulous ; Jaw, Edentulous

Objective: Several COVID-19 patients have overlapping comorbidities. The independent role of each component contributing to the risk of COVID-19 is unknown, and how some non-cardiometabolic comorbidities affect the risk of COVID-19 remains unclear. Methods: A retrospective follow-up design was adopted. A total of 1,160 laboratory-confirmed patients were enrolled from nine provinces in China. Data on comorbidities were obtained from the patients' medical records. Multivariable logistic regression models were used to estimate the odds ratio ( Results: Overall, 158 (13.6%) patients were diagnosed with severe illness and 32 (2.7%) had unfavorable outcomes. Hypertension (2.87, 1.30-6.32), type 2 diabetes (T2DM) (3.57, 2.32-5.49), cardiovascular disease (CVD) (3.78, 1.81-7.89), fatty liver disease (7.53, 1.96-28.96), hyperlipidemia (2.15, 1.26-3.67), other lung diseases (6.00, 3.01-11.96), and electrolyte imbalance (10.40, 3.00-26.10) were independently linked to increased odds of being severely ill. T2DM (6.07, 2.89-12.75), CVD (8.47, 6.03-11.89), and electrolyte imbalance (19.44, 11.47-32.96) were also strong predictors of unfavorable outcomes. Women with comorbidities were more likely to have severe disease on admission (5.46, 3.25-9.19), while men with comorbidities were more likely to have unfavorable treatment outcomes (6.58, 1.46-29.64) within two weeks. Conclusion Besides hypertension, diabetes, and CVD, fatty liver disease, hyperlipidemia, other lung diseases, and electrolyte imbalance were independent risk factors for COVID-19 severity and poor treatment outcome. Women with comorbidities were more likely to have severe disease, while men with comorbidities were more likely to have unfavorable treatment outcomes.
Adult ; Aged ; COVID-19/virology* ; China/epidemiology* ; Comorbidity ; Female ; Humans ; Male ; Middle Aged ; Retrospective Studies ; Severity of Illness Index ; Treatment Outcome