BACKGROUND:Precision attachment has been widely used in complete denture because of its strong retention, good appearance, comfort and durability. Among them, magnetic attachment and bal-cap attachment are commonly applied for mandibular complete denture.
OBJECTIVE:To compare the clinical effects of magnetic attachment, bal-cap attachment and traditional clasp retainer used in the mandibular removable partial denture.
METHODS:A total of 45 patients with dentition defects were included in this study, they were treated with magnetic attachment, bal-cap attachment and traditional clasp retention of mandibular removable partial denture. Fifteen patients received one means. The satisfaction of patients and the periodontal health of abutments were observed after 3 years.
RESULTS AND CONCLUSION:Comparison of the patient satisfaction showed that, the aesthetics, retention conditions, masticatory function and comfort in magnetic attachment group were significantly better than traditional clasp retention group (P<0.05). The aesthetics and comfort in bal-cap attachment group were also better than traditional clasp retention group (P<0.05). There were significant differences on the retention conditions and comfort between magnetic attachment group and bal-cap attachment group (P<0.05). Gingival index was the highest in magnetic attachment group, then in bal-cap attachment group, and the lowest in traditional clasp retention group (P<0.05). The abutment tooth mobility degree was the lowest in magnetic attachment group, then in bal-cap attachment group, and the highest in traditional clasp retention group (P<0.05). The periodontal pocket depth in magnetic attachment group and bal-cap attachment group was lower than that in traditional clasp retention group (P<0.05). The alveolar bone height was the highest in magnetic attachment group, then in bal-cap attachment group, and the lowest in traditional clasp retention group (P<0.05). Experimental findings indicate that, precision attachment over-denture retention superior to traditional clasp removable partial denture in mandibular denture repairing. Magnetic attachment can provide better retention power and better protect the health of periodontal tissue compared with bal-cap attachment.

BACKGROUND:Studies have shown that selection of implant crowns that directly impact the service life of implants and patient’s periodontal health is very important.
OBJECTIVE:To compare the clinical effects of Lava zirconia crowns, goal-platinum al oy ceramic crowns and silver-pal adium al oy crowns supplemented by dental implants used in the single missing posterior tooth.
METHODS:Sixty patients with first molar missing (120 teeth) were divided into three groups and treated with Lava zirconia, goal-platinum al oy ceramic and silver-pal adium al oy crowns applied to the dental implants for posterior column defects. The clinical restorative effects of three prostheses were compared.
RESULTS AND CONCLUSION:During 6-48 months of fol ow-up, the gingival edge coloring, gingival margin microleakage, the color of prosthesis of Lava zirconia al oy ceramic crowns and gold-platinum al oy ceramic crowns were better than those of silver-pal adium al oy crowns, and the gingival edge coloring and the color of prosthesis of Lava zirconia al oy ceramic crowns were better than those of gold-platinum al oy ceramic crowns, while the gingival margin microleakage of gold-platinum al oy ceramic crowns was better than that of Lava zirconia al oy ceramic crowns. Silver-pal adium al oy crowns were lower than Lava zirconia ceramic crowns and gold-platinum al oy ceramic crowns in the fracture extent. But silver-pal adium al oy crowns had the highest gingival index, the worst gingival health and rapidest and most severe plaque formation. Therefore, Lava zirconia al-ceramic crowns and gold platinum al oy-porcelain crown are ideal prostheses for implant restorations. The former has better biocompatibility, and the latter shows better marginal adaptation.

BACKGROUND:Palatal rugae assist for consonantal formation;however,effect of palatal rugae on phonetics has been previously reported to be involved in different complete denture base plates of recipients.OBJECTIVE:To qualitatively analyze the effe-cts of different palate base plate morphology on phonetics of edentulous jaw patients using a computerized speech lab.DESIGN,TIME AND SETTING:A contrast study was performed at the Department of Stomatology,Beijing Hospital of Healthy Administration,and at the Department of Otorhinolaryngology,Beijing Friendship Hospital affiliated to Capital Medical University between February 2007 and February 2008.PARTICIPANTS:Ten edentulous jaw patients wore complete denture with smooth surface and palatal rugae complete denture base.METHODS:Spike,voice onset time and transition of 10 edentulous iaw patients were measured by computerized speech lab when/da/,/ta/,/sa/,and/na/were pronounced.MAIN OUTCOME MEASURES:Spike.voice onset time and transition.RESULTS:Spikes were observed in all syllables.When/da/and/ta,were pronounced.voice onset time in the smooth surface group was significantly shorter than palatal rugae group(P<0.05):voice onset time of/d/and/t/in the palatal rugae group was similar to normal value(P>0.05).When/da/and/ta/ were pronounced,transition frequency in the smooth surface group was significantly lower than palatal rugae group(P<0.05),while that in the palatal rugae group was similar to normal value(P>0.05).CONCLUSION:As an anatomical landmark,palatal rugae contribute to phonetic restoration and consonant articulation of edentulous jaw patients.Computerized speech lab can quantitatively analyze phonetic changes after complete denture restoration and may be used as guidance for clinical dental prosthetics.

BACKGROUND:Hyaluronic acid has antioxidant, immune regulation, anti-inflammatory roles as wel as promotes wound healing. Hyaluronic acid is more and more applied in the treatment of chronic periodontitis and achieves a significant effect. OBJECTIVE: To observe the clinical effects of local application of sodium hyaluronate in the treatment of chronic periodontitis. METHODS:Sixty cases of chronic periodontitis (300 teeth) were selected. According to self-control method, the teeth in district A, 150 premolars or molars, were as experimental group, and other 150 teeth in district B served as control group. In the experimental group, periodontal scaling, subgingival scaling, and local application of Gengigel gel (0.2% hyaluronic acid) in the gingival sulcus were employed; in the control group, the treatment was same to that in the experimental group except local application of Gengigel gel. During 8-week folow-up, dental plaque index, sulcus bleeding index, probing depth, and clinical attachment loss were changed dynamicaly. RESULTS AND CONCLUSION:After treatment, al the measurement indexes were improved remarkably in the two groups. However, there was no difference in the dental plaque index between the two groups at 1, 4, 8 weeks after treatment. The sulcus bleeding index was lower in the experimental group than the control group at 1, 4, 8 weeks after treatment (P < 0.05). The periodontal probing depth of the experimental group was lower than that of the control group at 4 and 8 weeks (P < 0.05). The clinical attachment loss was lower in the experimental group than the control group at 8 weeks (P < 0.05). These findings indicate that periodontal treatment with local application of sodium hyaluronate in the gingival sulcus is significantly effective for the treatment of chronic periodontitis.

Objective To study the clinical features of senile salivary gland neoplasms. Methods A total of 104 cases of senile (beyond 60 years old) salivary gland tumors treated in the past 15 years were analysed. Results Among the 104 cases of senile salivary gland tumors, benigns(85.6%) was more than malignants; males(76.0%) was more than females, the ratio of M∶F was about 1.5∶1. Seventy-two cases(69.2%) were from the parotid gland, 19 (18.3%) from the submandibular gland, 6 (5.8%) from the sublingual gland, 7 cases(6.7%) from the minor salivary gland. Warthin tumor (34 cases) accounted for 32.7%(34/104) of all senile salivary gland tumors, and 47.2%(34/72) of senile parotid gland tumors, 54.8%(34/62) of benign parotid gland tumors. Conclusions The senile salivary gland tumor were mainly benign tumor; Warthim tumor is the most commonly seen and the parotid gland is the most frequently targeted organ. The incidence in males is higher than in females, patients at 60-70 years old (76.0%) are the main victims. Regional excision of parotid gland (resection of tumor together with its surrounding glands) was efficient for surgical treatment in the elderly.

0.05). The bone graft rate was 13% in senile group and 9% in non-senile group( P