上海口腔医学最新文献

Purpose: To explore the influence of gingival biotype and width of keratinized gingiva on peri-implant bone tissue, soft tissue health, and esthetic outcome of the papilla surrounding single posterior maxillary implants.

Methods: Seventy-eight patients who underwent single posterior maxillary implant surgery from May 2019 to September 2022 were selected, involving the placement of 78 implants. Based on periodontal probing outcomes one month post-restoration, the patients were divided into thin gingival biotype group(n=32) and thick gingival biotype group(n=46). Comparisons were made six months after implant restoration regarding buccal keratinized mucosa width(KMW), peri-implant bone tissue [implant bone loss(IBL)], soft tissue health [modified plaque index (mPLI), modified bleeding index for implants (mBLI), probing pocket depth (PPD)], and esthetic effect of the papilla [papilla index score (PIS), food impaction, gingival margin color satisfaction index (GMCS)]. Statistical analysis was performed with SPSS 27.0 software package.

Results: The thick gingival biotype group showed significantly greater keratinized gingival width compared to the thin gingival biotype group (P＜0.05). Spearman correlation analysis revealed a positive correlation between gingival biotype and keratinized gingival width(r=-0.416, P=0.000). For peri-implant bone tissue, bone loss in the thin gingival biotype group was significantly higher than that in the thick gingival biotype group. In soft tissue health, the probing pocket depth for implants in the thin gingival biotype group was significantly less than that in the thick gingival biotype group. In terms of esthetic effect of the papilla, PES score in the thin gingival biotype group was significantly lower than in the thick gingival biotype group(P＜0.05). Pearson correlation analysis showed a negative correlation between gingival biotype and papilla index score, GMCS, bleeding on probing, and PPD, but a positive correlation with food impaction, bone loss and mPLI(P＜0.05). The width of keratinized gingiva was positively correlated with papilla index score, GMCS, bleeding on probing and PPD, but negatively correlated with food impaction, bone loss and mPLI(P＜0.05). There was significantly difference between thin and thick gingival biotype groups for KMW >2 mm(P＜0.05). A significant difference was showed in thick gingival biotype group when KMW ≤2 mm and ＞2 mm(P＜0.05).

Conclusions: Gingival biotype and keratinized mucosa width significantly influence peri-implant bone and soft tissue health as well as esthetic outcome of the papilla around single posterior maxillary implants, offering guidance for predicting the long-term success and esthetic outcomes of implants.

Purpose: The movement trend of the posterior teeth and the distribution of the periodontal membrane stress were studied by using three-dimensional digital technology.

Methods: CBCT data of 88 patients admitted to our hospital from June 2017 to June 2022 were selected, and input into Mimics20.0 software for preliminary extraction of all parts and stored with STL files; then the data were repaired and optimized through Geomagic Studio 2014 software. With the help of normal phase extension, the invisible appliance and periodontal membrane were constructed. Finally, the six FEM models were simulated and observed by the current teeth in different groups. Statistical analysis was performed with SPSS 21.0 software package.

Results: The effect force of the largest periodontal membrane was distributed in the neck of the tooth, followed by the apical area, with the maximum effect force value in the NA group. In all accessory groups, the periodontal membrane maximum paradigm isoeffect force values of all patients in the accessory vertical rectangular group were significantly smaller than the values obtained in the horizontal rectangular group.

Conclusions: The design of orthodontic tooth accessories has a strong inhibition effect on the position movement of anterior teeth during recovery, which improves the accuracy of tooth three-dimensional movement to a certain extent. Meanwhile, the normal equivalent stress of the periodontal membrane of patients in the initial application of the invisible appliance without brackets is large.

Purpose: To summarize the ultrasonographic features of head and neck Castleman disease (CD), and to clarify its diagnostic key points.

Methods: Seven patients with head and neck CD confirmed by histopathology were collected from Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine. The clinical features and ultrasound findings of the patients were evaluated.

Results: Of the 7 patients (1 male and 6 females), the mean age at diagnosis was 31.4 years (7-60 years). All the cases were hyaline vascular type. On ultrasound, 3 lesions (42.9%) were located in the parotid gland, 4 lesions(57.1%) in the neck. All the lesions presented as a solitary, well-defined and solid mass without calcification. The echogenicity was markedly hypoechoic in 1 case(14.3%) and hypoechoic in 6 cases (85.7%). Of the 7 CD cases, 4 cases (57.1%) were heterogeneous masses with linear echogenic septa. All lesions had mixed pattern in vascularity on color Doppler sonography.

Conclusions: Most CDs in the head and neck represent as a markedly hypoechoic or hypoechoic lesion with mixed pattern in vascularity. The neoplasm may be characterized by the presence of linear echogenic septa within the mass.

Purpose: The fatigue resistance of mechanical nickel-titanium files was tested by phase-locked infrared flaw detection method, in order to timely detect instrument wear, providing reference for clinical safe use and timely abandonment of nickel-titanium files.

Methods: Twenty sets of mechanical nickel-titanium files were selected from Reciproc-Blue(RB), MTWO and S3 respectively, and resin simulated root canals with 60° and 90° bending were prepared, which were divided into 6 subgroups. The fatigue value after use, the number of uses before breaking and the length of fracture of file 25# of each group of files were recorded and compared with SPSS 26.0 software package.

Results: With the increase of the times of use, the fatigue value of the three kinds of files increased gradually. Among the two types of curved root canals, the number of uses before fracture in RB group was significantly increased compared with that in MTWO group and S3 group (P＜0.05). The number of uses of the three kinds of files in the 90° curved root canal were significantly less than in the corresponding groups in the 60° curved root canal(P＜0.05). There was no significant difference in the length of fracture among the three kinds of files(P＞0.05).

Conclusions: Phase-locked infrared flaw detection method can be used for non-destructive testing and quantitative analysis of the fatigue degree of nickel-titanium files.

Purpose: To evaluate the effect of standardized periodontal probing training on the teaching of periodontal clinical probing for undergraduates by using Florida probe system.

Methods: Twenty undergraduates who practiced in the Department of Periodontology of Changzhou Stomatological Hospital from May 2022 to November 2022 were selected as the study objects and randomly divided into two groups with 10 students in each group. The experimental group received standardized periodontal probing training, while the control group did not receive training. Two groups of students used the traditional probe and the Florida probe to probe the left and right half-mouth teeth of one patient. In addition, a periodontal specialist used Florida probe to conduct full oral examination of the same patient, and the results were compared with those of the two groups of students. SPSS 26.0 software package was used for statistical analysis of the obtained data.

Results: There was no significant difference of probing depth(PD) between undergraduates and periodontal specialist in the experimental group (P＞0.05), while there was significant difference in the control group (P＜0.05). In the control group, PD values in the anterior area were not statistically different from those of periodontal specialist (P＞0.05), while PD values in the posterior area were statistically different (P＜0.05). Both groups of patients reported that the Florida probe system was more comfortable.

Conclusions: Standardized periodontal probing training is helpful to improve the clinical probing ability of undergraduates. The use of Florida probe system can not only evaluate the teaching effect, but also improve the comfort level of patients, which is worthy of further application in the teaching course of periodontal probing for undergraduates.

Purpose: To investigate the effects of laser combined with periodontal basic treatment on periodontal indices, subgingival flora, adiponectin, matrix metalloproteinase-13 (MMP-13) and interleukin-1β (IL-1β) in patients with periodontitis.

Methods: A retrospective analysis was performed on 100 patients with periodontitis diagnosed and treated in Hengshui People's Hospital from December 2022 to July 2023. According to treatment methods, the patients were divided into control group (n=51) and experimental group (n=49). The control group received periodontal basic treatment, and the experimental group received laser treatment on the basis of the control group. The periodontal indexes, subgingival microflora, adiponectin, MMP-13, IL-1β and bone metabolic factors of gingival crevicular fluid before and after treatment were compared between the two groups, as well as the clinical therapeutic effect. Statistical analysis was performed with SPSS 22.0 software package.

Results: After treatment, probing depth(PD), bleeding on probing(BOP), gingival index(GI) and plaque index (PLI) in the experimental group were lower than before treatment (P＜0.05), PD, BOP and PLI in the control group were lower than before treatment (P＜0.05), and PD, BOP, GI and PLI in the experimental group were significantly lower than those in control group (P＜0.05). After treatment, Lactobacillus, Clostridium and Bacteroides in both groups were significantly lower than before treatment (P＜0.05), and the experimental group was significantly lower than the control group(P＜0.05). After treatment, adiponectin in gingival crevicular fluid increased in both groups compared with before treatment(P＜0.05), and MMP-13 and IL-1β in gingival crevicular fluid decreased in both groups compared with before treatment (P＜0.05), and adiponectin in gingival crevicular fluid in the experimental group was significantly higher than that in the control group (P＜0.05), MMP-13 and IL-1β in the experimental group were significantly higher than that in the control group (P＜0.05). After treatment, procollagenⅠtype N-terminal peptide (PINP), cross linked C-telopeptide of type Ⅰ collagen(CXT) and bone glaprotein (BGP) were significantly higher than those before treatment (P＜0.05), and the experimental group was significantly higher than the control group (P＜0.05). The total effective rate of the experimental group was significantly higher than that of the control group (P＜0.05).

Conclusions: Laser combined with periodontal basic treatment can effectively improve periodontal indexes, reduce subgingival flora, increase the levels of adiponectin and bone metabolic factor in gingival crevicular fluid, reduce the levels of MMP-13 and IL-1β in gingival crevicular fluid, and improve the clinical therapeutic effect in patients with periodontitis.

Purpose: To establish molar root canal model with micro-computed tomography (Micro-CT) and evaluate the removal efficiency of calcium hydroxide by different methods.

Methods: Eight molar teeth (24 root canals) extracted from the Department of General Dentistry, Shanghai Ninth People's Hospital from October 2023 to February 2024 were collected. Root canal preparation was instrumented by M3 according to standard root canal treatment procedures, then calcium hydroxide was injected into the root canal. One week later, the samples were randomly divided into 3 groups according to different irrigation methods(n=8): lateral opening syringe group, ultrasonic group and sonic vibration group. Micro-CT was used to reconstruct the root canal system before and after irrigation, and independent root canals were marked with different colors. The root canals were divided into upper root segment, middle root segment and apex segment. The volume of calcium hydroxide in each canal was calculated, and the clearance rate of calcium hydroxide was compared among the groups. SPSS 19.0 software package was used for statistical analysis.

Results: None of the three methods could completely remove calcium hydroxide from the root canal. When sodium hypochlorite was used as the flushing solution, the removal effect of ultrasonic group and sonic vibration group was significantly better than that of lateral opening syringe group(P＜0.05). The removal efficiency of calcium hydroxide by ultrasonic group and sonic vibration group was similar, and the difference was not statistically significant(P＞0.05). The removal rate of calcium hydroxide in apical segment was low.

Conclusions: Micro-CT can reconstruct the molar root canal model efficiently for evaluating the removal effect of calcium hydroxide. The removal efficiency of calcium hydroxide in ultrasonic group and sonic vibration group is similar, and both are better than that in lateral syringe group.

Purpose: To explore the efficacy of denture occlusal plate combined with comprehensive physical therapy for temporomandibular joint disc displacement without reduction(ADDwoR).

Methods: Sixty patients of ADDwoR and dentition defect or severely worn teeth who visited the Department of Orthodontics and Prosthodontics of Hengshui People's Hospital from January 2019 to December 2020 were selected and randomly divided into denture occlusal plate group (group A) and denture occlusal plate + comprehensive physical therapy group (group B) according to the treatment methods. Maximum mouth opening (MMO) and visual analog pain score(VAS) among all patients were recorded before treatment and every three weeks during three months of treatment. Cone-beam CT(CBCT) was taken before and 3 months after treatment. The changes in clinical efficacy indicators before and after treatment and CBCT data between the two groups were analyzed. Statistical analysis was performed with SPSS 26.0 software package.

Results: The differences of VAS of group A and B were statistically significant from before treatment to three weeks after treatment(P＜0.05), and group B decreases more. From 3 weeks after treatment, there was a significant difference of group B for MMO and VAS before treatment (P＜0.05). From 9 weeks after treatment, there was a significant difference of group A for MMO before treatment (P＜0.05), but there was no significant difference in MMO and VAS between group A and B(P＞0.05). CBCT showed narrowed anterior joint space, widened posterior joint space, enlarged superior joint space, decreased horizontal angle of the condyle and increased slope of joint nodules (P＜0.05). The difference between joint depth, anteroposterior diameter of the condyle, internal and external diameter was not significant (P＞0.05). There was significant differences in anterior, superior, and posterior joint space, condylar level angle, and slope of joint nodules of group B compared with group A(P＜0.05).

Conclusions: Denture occlusal plate can effectively improve symptoms of ADDwoR, and denture occlusal plate combined with comprehensive physical therapy can quickly improve mouth opening and reduce pain in the joint area.

Purpose: To compare and analyze the orthodontic effects of micro-implant screw support and flat guide plate on excessive deep overbite of lower anterior teeth.

Methods: Eighty-two patients with excessive deep overbite of the lower anterior teeth who were treated from January to December 2022 were selected and randomly divided into two groups (41 in each group) by random number table method. Both groups were treated with straight wire arch orthodontic technology, and the anterior teeth were supported by micro-implant screws (micro-implant screw group) and flat guide plates (flat guide plate group), respectively. The effect of upper anterior tooth compression, changes in occlusal plane, and apical absorption were compared between the two groups. SPSS 25.0 software package was used for statistical analysis.

Results: There were no significant changes in SNA angle, SNB angle, ANB angle, U1-PP, U6-PP, and L6-MP before and after treatment between the two groups (P＞0.05). L1-MP significantly increased in both groups after treatment than before treatment(P＜0.05). There was no significant difference in bite opening, Spee curve depth, U1 depression, L1 depression, U6 elongation, L6 elongation and occlusal opening time between the two groups before and after treatment(P＞0.05). The root apex absorption of the mandibular central incisors and lateral incisors in the micro-implant screw group was significantly lower than that in the flat guide plate group(P＜0.05), while there was no significant difference in root apex absorption between the two groups of canines(P＞0.05).

Conclusions: Both micro-implant screw support and flat guide plate can effectively lower the mandibular anterior teeth in the treatment of deep overbite in adults, with good orthodontic effects. However, the latter can lead to increased root resorption.

Purpose: To compare the mucosal morphological difference in distal-extension area of mandibular dentition defect taken by intra-oral digital scanning and selective pressure impression techniques.

Methods: Seventeen patients with Kennedy Class I and Class II dentition defect in lower jaw were included, including twenty-two distal-extensions. Intraoral digital scanning and functional impression technique were taken in each patients, respectively. Laboratory cast scanner was used to scan the plaster casts made from the selective pressure impression to obtain the three-dimensional data. All the data were stored in STL format. The 3D data collecting from intra-oral digital scanning and selective pressure impression from the same patient were compared by Geomagic Control 2014 software. Root mean square of 2.5mm diameter area was calculated in 5,10,15 mm from terminal tooth. Pearson's correlation test was used to analyze the correlation of the distance and morphological difference with SPSS 20.0 software package.

Results: Mean mucosal morphological difference of jaw distal-extension edentulous area taken by intra-oral digital scanning and selective pressure impression techniques was (0.37±0.12) mm. There was positive correlation between distance from terminal tooth and mucosal morphological difference(P＜0.05). Morphological differences in 5, 10, 15 mm from terminal tooth were (0.14±0.11) mm, (0.22±0.13) mm and (0.39±0.16) mm, respectively.

Conclusions: In this study, there was positive correlation between the length of distal-extension edentulous area and mucosal morphological difference, while the kind of ridge defect and mucosal thickness may also affect the morphological difference quantity.