Prognosis and complications of mature teeth after lateral luxation: A systematic review

BackgroundDental trauma injuries are frequent in children and adolescents and can result in a sequela of future complications. Lateral luxation injuries are diagnosed when a tooth becomes displaced in a position other than axial and is often associated with alveolar bone fracture. Although the tooth is not immediately lost, pulp canal obliteration or pulpal necrosis can occur. The objective of this systematic review was to gather existing data on lateral luxation injuries to mature teeth to evaluate their overall prognosis and reported complications.Types of Studies ReviewedThe authors conducted a systematic search of the literature using MEDLINE, PubMed, Embase, and Cochrane databases in February 2019. They hand searched reference lists to identify additional literature. The authors included prospective and retrospective observational studies in the search. They screened a total of 291 articles, downloaded 28 articles, and included 4 articles in the study.ResultsThe most frequent complication reported for mature teeth with lateral luxation was pulpal necrosis (44.2%). Less frequent findings included surface resorption (14.0%), inflammatory resorption (8.5%), pulp canal obliteration (8.1%), and replacement resorption (0.9%). The included studies were cohort studies, which resulted in great heterogeneity, and the authors could not attempt a meta-analysis.Conclusions and Practical ImplicationsA large number of permanent teeth that experience lateral luxation are at risk of developing pulpal necrosis and other complications. Careful follow-up is required for these patients to treat complications as early as possible. Furthermore, the authors of this systematic review emphasize the importance of consistent reporting of dental trauma outcomes.     

Videofluoroscopic Evaluation of the Influence of a Gradually Reducing Femoral Radius on Joint Kinematics During Daily Activities in Total Knee Arthroplasty

BackgroundParadoxical anterior translation in midflexion is reduced in total knee arthroplasties (TKAs) with a gradually reducing femoral radius, when compared to a 2-radii design. This reduction has been shown in finite element model simulations, in vitro tests, intraoperatively, and recently also in vivo during a lunge and unloaded flexion-extension. However, TKA kinematics are task dependent and this reduction has not been tested for gait activities.MethodsThirty good outcome subjects (≥1 year postoperatively) with a unilateral cruciate-retaining TKA with a gradually reducing (n = 15) or dual (n = 15) femoral radius design were assessed during 5 complete cycles of level walking, stair descent (0.18-m steps), deep knee bend, and sitting down onto and standing up from a chair, using a moving fluoroscope (25 Hz, 1 ms shutter time). Kinematic data were extracted by 2D/3D image registration.ResultsTibiofemoral ranges of motion for flexion-extension, abduction-adduction, internal-external rotation, and anteroposterior (AP) translation were similar for both groups, whereas the pattern of AP translation-flexion-coupling differed. The subjects with the dual-radii design showed a sudden change in direction of AP translation around 30° of flexion, which was not present in the subjects with the gradually reducing femoral radius design.ConclusionThrough the unique ability of moving fluoroscopy, the present study confirmed that the gradually reducing femoral radii eliminated the paradoxical sudden anterior translation at 30° present in the dual-radii design in vivo during daily activities, including gait and stair descent.     

Splinted and unsplinted overdenture attachment systems: A systematic review and meta‐analysis

Splinted and unsplinted overdenture attachment systems have unique advantages and disadvantages. The aim of the present systematic review was to determine the influence of splinted and unsplinted overdenture attachment systems on the marginal bone loss, prosthetic complications and implant survival rate. PubMed/MEDLINE , Scopus and Cochrane databases were searched for articles published up to October 2017, using the following search terms: “overdenture AND attachment OR overdenture AND bar OR overdenture splinted.” The PICO question “Do splinted overdenture attachment systems promote better clinical results in comparison to unsplinted systems?” was evaluated. Eligible studies included randomized controlled clinical trials, prospective studies with at least 10 participants and a minimum follow‐up of 6 months, and studies published in English that compared splinted and unsplinted attachment systems within the same study. The 95% confidence interval (CI ) was considered for all outcomes analysed. After completion of the different steps in the article selection process, nine articles were included in the qualitative and quantitative analyses. A total of 984 implants were placed in 380 patients (mean age: 62.8 years). The meta‐analysis demonstrated no statistically significant differences between splinted and unsplinted attachment systems with regard to marginal bone loss (P  = .39; MD : ?0.11; 95% CI : ?0.37 to 0.14), complications (P  = .31; RR : 1.26; CI : 0.80‐1.99) and implant survival rate (P  = .14; RR : 0.37% CI : 0.10‐1.36). In addition, splinted and unsplinted overdenture attachment systems achieved similar results with regard to marginal bone loss, prosthetic complications and implant survival rate.     

The effects of elevated fibroblast growth factor 23 on mandibular growth in rats

ObjectiveThe aim of this study is to elucidate the local effects of fibroblast growth factor 23 (FGF23) in on mandibular condylar growth in growing rats.DesignGrowing Sprague–Dawley rats received intra-temporomandibular joint injections of phosphate buffer solution (PBS), adenovirus-mediated green fluorescent protein (Ad-GFP) or adenovirus-mediated fibroblast growth factor 23 (Ad-FGF23), which were marked as groups A, B, and C, respectively. In vitro, we treated rat mandibular cartilage chondrocytes with PBS, Ad-GFP, and Ad-FGF23.ResultsThe mandibular condyles in group C grew smaller sizes than those in the other control groups due to significant differences among the experimental and control groups with the value of C–D, Q–R (P ≤ 0.05), accompanied by diminished bone mass of sub-cartilage condyles via micro CT analysis. Histologically, the length of the hypertrophic zone was diminished and was associated with decreasing chondrocyte proliferation in group C. Quantitative real-time PCR indicated significant decreases in the expression of chondrogenesis marker genes, including Type X collagen (Col X) and SRY-type box 9 (Sox 9). Moreover, elevated Ad-FGF23 suppressed chondrocyte proliferation and the expression of the chondrogenic differentiation markers Col X and Sox 9 of in vitro.ConclusionsLocal injection of FGF23 suppressed the development and decreased the bone mass of condyles through the decreasing the formation of condylar cartilage, specifically by regulating condylar cartilage cell viability and chondrogenesis expression.     

����������������յ����������Ԥ��

牙根吸收是正畸治疗过程中常见的并发症之一，虽然严重的牙根吸收很少见，但其作为一种无法预料的并发症多年来一直困扰着正畸医生。本文将对正畸相关性牙根吸收的早期诊断与预防做一综述。     

Effects of laparoscopic Roux-en-Y gastric bypass on bone mineral density and markers of bone turnover

BackgroundDespite multiple beneficial effects of weight loss after laparoscopic Roux-en-Y gastric bypass (LRYGB), the influence on bone mineral density (BMD) remains largely unknown. Our objective was to evaluate the changes in BMD and serum/urine bone markers after LRYGB.MethodsThirty-four women undergoing LRYGB were prospectively enrolled and underwent bone densitometry and serum/urine analysis preoperatively and 1 year postoperative. Changes≥.025 g/cm² in hip, femoral neck, and spine BMD and decreases>2% in total BMD were considered significant. Statistical analysis included paired t tests and McNemar’s test.ResultsMean age was 44.6 years. Body mass index at the preoperative and 1-year postoperative intervals were 46.7 and 29.6 kg/m², respectively. Mean hip, femoral neck, and spine (L1–L4) BMD was 1.191 versus 1.087 g/cm² (P< .001), 1.105 versus 1.032 g/cm² (P< .001), and 1.323 versus 1.277 g/cm² (P< .001) at the preoperative and 1 year postoperative intervals, respectively. Mean total BMD decreased from 1.328 preoperatively to 1.251 g/cm² at 1 year postoperative (P<.001). The decreases in BMD were 5.8%, 6.5%, 3.5%, and 8.8% for hip, femoral neck, spine (L1–L4) and total BMD from preoperative to 1 year postoperative. The proportion of patients with low vitamin D levels decreased from 55% preoperatively to 21% at 1 year postoperative (P = .004). Elevated osteocalcin and bone alkaline phosphatase was observed in 4% and 63% (P<.001), and 14% and 41% (P = .011) of patients preoperatively and at 1 year postoperative, respectively.ConclusionBMD and bone markers changed significantly after LRYGB. Current recommendations for supplementation in post-LRYGB women may need to be reevaluated.     

前牙压低技术在深覆(牙合)患者矫治中的应用进展

深覆(牙合)的治疗是口腔正畸矫治的难点之一.对于伴有垂直生长型、长面型或上唇过短、露龈笑的患者,就更需要医生进行细致诊断,合理选择矫治方法和器械.通过单纯地压低前牙能较为有效地治疗该类患者的深覆(牙合)畸形.目前,临床常用的压低前牙的方法主要有三段式片段弓技术、多用途弓技术、J钩联合高位牵引技术和微种植支抗技术等.本文...     

Association between occlusal force distribution in implant overdenture prostheses and residual ridge resorption

This study aimed to investigate residual ridge resorption (RRR) of anterior and posterior maxillary and mandibular edentulous ridges, in patients treated with mandibular implant overdentures (IOD) and compare with conventional complete denture (CD) wearers, and to determine at each location, the association of RRR with the occlusal forces distribution and other patients’ variables. The anterior and posterior RRR of IOD (six males, 17 females) and CD (12 males, 11 females) groups were determined using baseline and follow‐up dental panaromic radiographs (DPT) (mean intervals 4 ± 1·8 years). The bone ratios were calculated using proportional area: anatomic to fixed reference areas and mean difference of ratios between the intervals determined RRR. The ridge locations included anterior and posterior maxillary and posterior mandibular arches. The T‐Scan III digital occlusal system was used to record anterior and posterior percentage occlusal force (%OF) distributions. There were significant differences in anterior and posterior %OF between treatment groups. Two‐way anova showed RRR was significant for arch locations (P = 0·005), treatment group (IOD versus CD) (P = 0·001), however, no significant interaction (P = 0·799). Multivariate regression analyses showed significant association between RRR and %OF at anterior maxilla (P = 0·000) and posterior mandible (P = 0·023) and for treatment groups at posterior maxilla (P = 0·033) and mandibular areas (P = 0·021). Resorption was observed in IOD compared to CD groups, with 8·5% chance of less resorption in former and 7·8% in the latter location. Depending on arch location, ridge resorption at various locations was associated with occlusal force distribution and/or treatment groups (implant prostheses or conventional complete dentures).