Body posture plays an important role in the normal oropharyngeal swallowing process. We aimed to clarify the effects of trunk angle on the biomechanics of the tongue, hyoid, and suprahyoid and infrahyoid muscles during normal oropharyngeal swallowing. For this purpose, fifteen healthy male participants (aged 27.7 ± 1.8 years) were recruited. They swallowed 15 ml of water in three random trunk angles (90°, 60°, 30°), and tongue pressure, hyoid bone movement, and the activity of the suprahyoid and infrahyoid muscles were monitored simultaneously by a non-invasive sensing system. Then, the temporal sequence as well as the parameters such as duration, peak value, and interval of the above-mentioned oropharyngeal structural motions were assessed. Results showed that the temporal sequence of tongue pressure, hyoid motion, and myoelectric activities during oropharyngeal swallowing was stable without any variation among the three postures. As the body gradually inclined, the onset and offset of the hyoid stationary phase and the offset of hyoid movement were delayed, and the hyoid elevation phase was prolonged (p < 0.05). No significant differences were detected for any of the parameters of tongue pressure (p > 0.05) except for tongue pressure duration at the anterior part (p < 0.05). In addition, no significant postural effects were observed for the duration, peak value, and electromyographic area of the suprahyoid muscle or infrahyoid muscle (p > 0.05). These findings suggest that trunk angle had no effect on the biomechanical sequence of the tongue, hyoid, and muscles during oropharyngeal swallowing in healthy adults, and the oropharyngeal structures will accommodate and finely regulate according to body posture.

It is commonly accepted that exposure to stress may cause overactivity in the orofacial muscles, leading to consistent muscle pain, which is the main symptom of temporomandibular disorders. The central neural mechanism underlying this process, however, remains unclear. The locus coeruleus is considered to play an important role in stress-related behavioral changes. Therefore, the present study was designed to examine the role of locus coeruleus neurons in masseter overactivity induced by stress. C57BL/6 mice were subjected to chronic restraint stress for 14 days to establish an animal model. The behavioral changes and the electromyography of the masseter muscle in mice were measured. The expression of Fos in locus coeruleus was observed by immunofluorescence staining to assess neuronal activation. A chemogenetic test was used to inhibit locus coeruleus neuronal activity, and the behavioral changes and electromyography of the masseter muscle were observed again. The results exhibited that chronic restraint stress could induce anxiety-like behavior, overactivity of the masseter muscle, and significant activation of locus coeruleus neurons in mice. Furthermore, inhibition of noradrenergic neuron activity within the locus coeruleus could alleviate stress-induced anxiety behavior and masseter muscle overactivity. Activation of noradrenergic neurons in locus coeruleus induced by stress may be one of the central regulatory mechanisms for stress-induced anxiety-like behaviors and overactivity of masseter muscles.

Objective To investigate the histological damage recovery of temporomandibular joint condylar cartilage caused by chronic unpredictable moderate stress, aiming to provide an experimental basis for the prevention and treatment of temporomandibular disorder. Methods This animal experiment was approved by the Laboratory Animal Ethical Inspection, School of Stomatology, The Fourth Military Medical University (No. 2020081). 60 male SD rats were randomly divided into control group, stress group, and 2-, 4- and 8-week post-stress recovery groups. Rats were subjected to chronic unpredictable moderate stress (CUMS) for 8 weeks including damp sawdust for 24 hours, tilted cage for 12 hours, noise for 4 hours, light/dark cycle reversal, water immersion, tail clamp, and restraint stress. The serum assessment, behavioral tests, histological and ultrastructural observation were performed 2-, 4- and 8-weeks after stress factors were removed. Serum levels of adrenocorticotropic hormone (ACTH) and corticosterone (CORT) were determined with ELISA. The sucrose preference test (SPT) and the forced swim test (FST) were used to assess the depressive-like behavior. The expression level of interleukin-1α (IL-1α) and matrix metalloproteinases-3 (MMP-3) were determined by Immunohistochemistry and Western blot. Results At the end of 8 weeks of CUMS, the serum levels of CORT and ACTH were significantly higher in stress group compared with control group (P<0.01). The sucrose preference decreased significantly and the immobility time increased significantly in the stressed rats compared with those in the control group, indicating a successful establishment of CUMS. The condylar cartilage showed significant degenerative changes, with disorganized collagen fibers and reduced proteoglycan synthesis on the cartilage surface. IL-1α and MMP-3 were expressed in the intracellular and extracellular matrix of the condylar cartilage, and their expression levels were increased (P<0.01). After 2 weeks of stress removal, the serum levels of CORT and ACTH were decreased but higher than control group (P<0.01), and behavioral changes were still different from the control group (P<0.01); the loosened collagen fibers could still be seen on the surface of condylar cartilage, and some free cell areas were visible within the proliferative layer; additionally, IL-1α and MMP-3 expression in the condyle was reduced in all layers of cartilage when compared with the stress group, but was still higher than in the control group (P<0.01). After 4 weeks of stress removal, the serum levels of CORT and ACTH changes returned to normal levels and behavioral changes were still different from control group (P<0.05); a few collagen fibers could be seen on the surface of the condylar cartilage and the expressions of IL-1α and MMP-3 decreased significantly compared with the stress group (P<0.01), with the similar level of IL-1α (P>0.05) and higher expression of MMP-3 comparing with the control group (P<0.01). After 8 weeks of stress removal, behavioral changes returned to normal levels, with no statistically significant differences compared with the control group (P>0.05). The condylar collagen fibers increased and showed a corrugated pattern, and no serious subchondral bone damage as well as irreversible damage occurred. Both of the expression levels of IL-1α and MMP-3 approached those of the control group after 8 weeks of stress removal (P>0.05). Conclusion The behavioral changes and condylar cartilage damage caused by CUMS could be self-repaired. The decline in IL-1α and MMP-3 expression may be one of the intrinsic mechanisms of this self-repair process.

Objective: To confirm the effect of fluid with different viscosity on the normal biomechanical sequence of oropharyngeal swallowing in healthy males. Methods: Fifteen healthy male subjects [(27.7±1.8) years old] were recruited from November 2011 to February 2012 and instructed to swallow 15 ml of water (W), nectar-like fluid (N), and honey-like fluid (H) in an upright sitting position. The sensing system was consisted of tongue pressure sensor sheet, bend sensor, surface electrodes and microphone. They were used to monitor tongue pressure, hyoid activity, surface electromyography (EMG) of swallowing-related muscles and swallowing sound, respectively. The swallowing sound was chosen as the reference time. The significance of biomechanical sequence of structural events was determined by repeated-measures analysis of variance (ANOVA). Results: When swallowing liquid of any consistency, hyoid premotor and suprahyoid muscle electromyography (EMG) appeared synchronously (P>0.05), followed by the simultaneous appearances of hyoid rapid movement, peak time of suprahyoid muscle EMG, onset of infrahyoid muscle EMG, and anterior tongue pressure production (P>0.05). The peak time of infrahyoid muscle EMG was very close to the peak time of anterior tongue pressure (P>0.05), and both of them were earlier than the time that the hyoid reaching the highest position (P<0.05). At last, the time that the hyoid departing the highest position was synchronized with the disappearances of suprahyoid muscle EMG, infrahyoid muscle EMG, and tongue pressure (P>0.05). The tongue pressure production and peak time of tongue pressure arose from anterior to posterior along the midline of hard palate during normal swallowing, with the significances for tongue pressure production between the anterior site and the middle site (W: P=0.035, N: P=0.027, H: P=0.013) as well as the anterior site and the posterior site (W: P<0.001, N: P<0.001, H: P<0.001), while the appearance and peak time of the circumferential tongue pressure were very close (P>0.05). The increase of fluid viscosity did not affect the biomechanical sequence of the above structural physiological movements during normal swallowing. There were statistically significant differences between the hyoid premotor and the onset of suprahyoid muscle EMG when swallowing the honey-like liquid [(-1.03±0.47) and (-0.90±0.50) s] and water[(-0.87±0.32) and (-0.74±0.31) s] (P<0.001). Among the delayed structural events, except for the onset of infrahyoid muscle EMG and the tongue pressure production on the anterior site (P>0.05), the occurrences of all the parameters in swallowing honey-like fluid were significantly later than those in swallowing water (onset of hyoid rapid movement, P=0.007; time of hyoid reaching the highest position, P=0.034; time of hyoid departing the highest position, P=0.041; offset of hyoid movement, P=0.035; peak time of suprahyoid muscle EMG: P=0.040; offset of suprahyoid muscle EMG, P=0.014; peak time of infrahyoid muscle EMG: P=0.042; offset of infrahyoid muscle EMG, P=0.028; peak time of Ch.1: P=0.045; offset of Ch.1: P=0.012; onset of Ch.2: P=0.038; peak time of Ch.2: P=0.009; offset of Ch.2: P=0.034; onset of Ch.3: P=0.043; peak time of Ch.3: P=0.011; offset of Ch.3: P=0.026;onset of Ch.4: P=0.040; peak time of Ch.4: P=0.038; offset of Ch.4: P=0.033; onset of Ch.5: P=0.046; peak time of Ch.5:P=0.028; offset of Ch.5: P<0.001), but not for those between nectar-like fluid and honey-like fluid (P>0.05). Conclusions: The alteration of fluid viscosity did not affect healthy male biomechanical sequence of tongue, hyoid and swallowing-related muscles during normal swallowing. The biomechanics of the oropharyngeal structures is physiologically regulated with the alteration of fluid viscosity to ensure swallowing safely and smoothly.

目的:报道 1 例前牙区多牙位复杂牙外伤合并牙槽窝骨壁骨折,经过多学科联合成功治疗的方法与经验.诊治经过:采用外伤牙再植、再植牙固定术,联合牙槽骨增量、植入浓缩生长因子等方法,对该病例进行规范化联合治疗.结果:经过 1 个月、3 个月、1 年、2 年、3 年、4 年的追踪观察,患者外伤牙再植成功,牙均无松动、无变色,获得良好疗效.结论:对于伴有牙槽窝骨壁骨折的复杂牙外伤,通过准确的病情分析及预后判断,采用多学科的联合治疗方法,可取得良好的预后效果.

以粘接固位为基础的后牙冠方修复是一种更加保守且生存率高的修复方式,目前己被广泛应用.该文以多数学者提出的基牙预备原则和研究为基础,结合实际临床操作病例,从患牙的术前分析、去除龋坏组织、剩余牙体组织分析和抗力形预备、修复空间预备、即刻牙本质封闭和洞形优化设计这些临床操作步骤来介召后牙大面积缺损粘接间接修复牙体预备的规范化操作过程.

目的 观察慢性束缚应激后,小鼠清醒状态下咬肌肌电水平以及支配咬肌运动的三叉神经运动核(trigeminal motor nucleus,Vmo)神经元的变化,为探究心理因素与颞下颌关节紊乱病发生的相关中枢调控机制提供实验依据.方法 32 只雄性小鼠被随机分为对照组、应激组,对应激组小鼠施加 4h/d、连续 14d的慢性束缚应激;对照组小鼠正常饲养.14 d后,通过旷场实验与高架十字迷宫实验观察小鼠的行为学改变;检测清醒状态下小鼠咬肌肌电水平;采用全细胞膜片钳技术观察Vmo神经元的电生理特性,并利用免疫组织荧光技术观察Vmo内Ⅰ型、Ⅱ型囊泡膜谷氨酸转运体(vesicular glutamate transporter 1/2,VGLUT1/2)的表达情况.结果 应激组小鼠在旷场实验的中央活动时间(P=0.0004)与中央活动路程(P=0.0004)均显著低于对照组;高架十字迷宫实验中应激组小鼠的开臂进入次数百分比(P=0.0002)与滞留开臂时间百分比(P=0.0013)均显著低于对照组,显示存在明显的焦虑样行为.对照组和应激组小鼠在应激开始前,咬肌累积肌电(integral electromyography,iEMG)(P=0.8779)及振幅均方根(root mean square,RMS)(P＞0.9999)均无明显差异;应激结束后,应激组小鼠咬肌的iEMG(P=0.0004)和 RMS 值(P= 0.0001)均显著高于对照组.对照组小鼠在应激前后的 iEMG(P= 0.7989)和 RMS 值(P＞0.9999)比较无显著差异;应激组小鼠在应激结束后,其咬肌的iEMG(P=0.0011)和RMS值(P=0.0019)显著高于应激前水平.电生理结果显示,在电流钳模式下,当输入 60、80、100 pA电流时,应激组小鼠Vmo神经元的放电频率显著高于对照组(P＜0.05);应激组小鼠Vmo神经元的自发性兴奋性突触后电流频率(P=0.0030)与幅度(P=0.0002)显著高于对照组.免疫组织荧光染色结果显示,应激组小鼠Vmo部位的VGLUT1(P=0.0010)与VGLUT2 荧光强度(P=0.0013)均显著高于对照组.结论 慢性束缚应激能够导致小鼠的焦虑样行为及咬肌肌电活动水平的增高.应激后脑内Vmo神经元兴奋性升高,其受到的谷氨酸能兴奋性投射增多,可能是束缚应激造成咬肌肌电活动水平升高的中枢机制之一.

Type H vessels couple angiogenesis with osteogenesis, while sympathetic cues regulate vascular and skeletal function. The crosstalk between sympathetic nerves and type H vessels in bone remains unclear. Here, we first identify close spatial connections between sympathetic nerves and type H vessels in bone, particularly in metaphysis. Sympathoexcitation, mimicked by isoproterenol (ISO) injection, reduces type H vessels and bone mass. Conversely, beta-2-adrenergic receptor (ADRB2) deficiency maintains type H vessels and bone mass in the physiological condition. In vitro experiments reveal indirect sympathetic modulation of angiogenesis via paracrine effects of mesenchymal stem cells (MSCs), which alter the transcription of multiple angiogenic genes in endothelial cells (ECs). Furthermore, Notch signaling in ECs underlies sympathoexcitation-regulated type H vessel formation, impacting osteogenesis and bone mass. Finally, propranolol (PRO) inhibits beta-adrenergic activity and protects type H vessels and bone mass against estrogen deficiency. These findings unravel the specialized neurovascular coupling in bone homeostasis and regeneration.

Root resorption (RR) is a common complication of traumatic dental injuries (TDIs), which could result in tooth loss and affect life in severe cases. The management of a traumatized tooth with RR remains a challenge for clinicians. In our presented cases, the impacted teeth had a history of trauma and underwent thorough non-surgical endodontic treatment; however, RR still occurred months later and could be observed through a periapical radiograph. Therefore, root canal therapy was performed under a dental microscope with a quick-setting calcium silicate cement to repair the RR site. After a long follow-up, the affected teeth showed almost complete healing of the periradicular tissues without sign of RR. This report demonstrates that external root absorption is typically a consequence of traumatized teeth. However, to date, there is still no effective method for its treatment. Here, we successfully applied microscopical surgery to the traumatized teeth experiencing root absorption and provided them with a new healing opportunity.

Bolus volume is very important in the biomechanics of swallowing. By noninvasively characterizing swallow responses to volume challenges, we can gain more knowledge on swallowing and evaluate swallowing behavior easily. This study aimed to evaluate the impact of bolus volume on the biomechanical characteristics of oropharyngeal swallowing events with a noninvasive sensing system. Fifteen healthy male subjects were recruited and instructed to swallow 5, 10, and 15 ml of water. The sensing system consisted of a tongue pressure sensor sheet, bend sensor, surface electrodes, and a microphone. They were used to monitor tongue pressure, hyoid activity, surface EMG of swallowing-related muscles, and swallowing sound, respectively. In addition to the onset, the peak time and offset of the above four structures, certain characteristics, such as the duration, peak value, and interval of the structure motions, were measured during the different drinking tasks. The coordination between the hyoid movement and tongue pressure was also assessed. Although no sequence of the structural events changed with volume, most of the timings of the structural events were significantly delayed, except for certain hyoid activities. The swallowing volume did not affect the active durations of the monitored structures, the peak values, or intervals of tongue pressure and supra- and infrahyoid muscle activity, but certain hyoid kinetic phases were prolonged when a larger volume was swallowed. Additionally, sequential coordination between hyoid movement and tongue pressure was confirmed among the three volumes. These findings suggest that oropharyngeal structural movements change in response to bolus volume to facilitate safe swallowing. The noninvasive and quantitative measurements taken with the sensing system provide essential information for understanding normal oropharyngeal swallowing.

Due to the complexity of the biomolecules and titanium (Ti) combination, it is a challenge to modify the implant surface with biological cytokines. The study proposed a new method for immobilizing cytokines on implant surface to solve the problem of low osseointegration under type 2 diabetes mellitus (T2DM) condition. This new modified protein that connected Ti-binding artificial aptamer minTBP-1 with Insulin-like growth factor I (IGF-I), had a special strong affinity with Ti and a therapeutic effect on diabetic bone loss. According to the copies of minTBP-1, three proteins were prepared, namely minTBP-1-IGF-1, 2minTBP-1-IGF-1 and 3minTBP-1-IGF-1. Compared with the other modified proteins, 3minTBP-1-IGF-1 adsorbed most on the Ti surface. Additionally, this biointerface demonstrated the most uniform state and the strongest hydrophilicity. In vitro results showed that the 3minTBP-1-IGF-1 significantly increased the adhesion, proliferation, and mineralization activity of osteoblasts under T2DM conditions when compared with the control group and the other modified IGF-1s groups. Real-time PCR assay results confirmed that 3minTBP-1-IGF-1 could effectively promote the expression of osteogenic genes, that is, ALP, BMP-2, OCN, OPG, and Runx2. All these data indicated that the 3minTBP-1-IGF-1 had the most efficacious effect in promoting osteoblasts osteogenesis in diabetic conditions, and may be a promising option for further clinical use.

Periodontitis is the leading cause of tooth loss in adults, and psychological factors play an important role in the development of periodontitis. To elucidate the adverse effects of psychological stress on the inflammatory process and redox status of periodontitis tissue, fifty male Sprague-Dawley rats were divided into the control, experimental periodontitis, psychological stress, experimental periodontitis plus psychological stress, and experimental periodontitis plus psychological stress plus fluoxetine groups. Chronic unpredictable mild stress (CUMS) was used to establish psychological stress, and silk ligature was used to induce experimental periodontitis. Four weeks later, stressed rats showed altered behaviour, serum hormone levels, and sucrose preference. More obvious alveolar bone loss and attachment loss and higher protein expressions of inflammatory cytokines were observed in the experimental periodontitis plus psychological stress group. The combination of CUMS and periodontitis had synergistic effects on increasing hypoxia-inducible factor-1α (HIF-1α) protein expression and reactive oxygen species (ROS) and malondialdehyde (MDA) contents and decreasing antioxidant enzyme activities compared with those in the stress or periodontitis groups. Moreover, psychological stress further increased p-IκBα and p-NF-κB p65 protein levels and decreased IκBα protein levels in periodontitis rats. Fluoxetine administration alleviated the adverse effects of psychological stress on the progression of periodontitis in rats. These results hint us that psychological stress could aggravate inflammation in periodontitis tissues, which may be partly due to local worsening of oxidative damage and further activation of the nuclear factor kappa-B (NF-κB) signalling pathway.

Psychological stress is commonly accepted to be closely associated with masticatory muscle disorder, which is the main symptom of temporomandibular disorder (TMD). Previous studies have confirmed that exposure to stress may cause masticatory muscle hyperactivity. However, the central mechanism underlying this process remains unclear. The mesencephalic trigeminal nucleus (Vme), which resides in the brainstem, is the primary afferent center for masticatory proprioception and plays a key role in oral–motor movements by projecting to the trigeminal motor nucleus (Vmo). Therefore, the present study was designed to examine the role of Vme neurons in masseter overactivity induced by chronic stress. We found that subjecting mice to restraint stress (6 h/day) for 14 days caused significant anxiety-like behavior, obvious masseter overactivity, and markedly enhanced electrophysiological excitability of Vme neurons. By using anterograde tract tracing combined with immunofluorescence staining methods, we observed vesicular glutamate transporter 1 (VGLUT1)-positive glutamatergic projections from the Vme to the Vmo. Moreover, chronic restraint stress (CRS) elevated the expression of VGLUT1 and choline acetyltransferase (ChAT) in Vmo. Furthermore, administration of VGLUT1-targeted short hairpin RNA (shRNA) into the bilateral Vme significantly suppressed the enhanced overexcitability of Vme neurons, downregulated the overexpression of VGLUT1 and ChAT in the Vmo, and attenuated the elevated overactivity of the masseter caused by CRS. Taken together, we showed that CRS can excite neurons in the Vme, enhancing glutamatergic excitatory projections from the Vme to the Vmo and resulting in masseter muscle overactivity. These findings provide us with a novel central mechanism underlying the correlation between psychological factors and TMD.

BACKGROUND AND OBJECTIVE:Psychological stress causes structural and metabolic dysfunction of masseter muscles. The anti-inflammatory and anti-oxidative polyphenol curcumin plays a local antioxidant role in rat masseter muscles under psychological stress by an as-yet-unknown mechanism. The present study aimed to assess curcumin anti-inflammatory and anti-oxidative effects on masseter muscle and its possible molecular mechanisms. METHODS:We constructed a rat model of chronic unpredictable moderate stress (CUMS). Psychological stress was assessed by determining the levels of adrenocorticotropic hormone (ACTH) and cortisol in serum. Enzyme-linked immunosorbent assays measured inflammatory cytokines and markers of oxidative stress in masseter muscles. Levels of high-mobility group box 1 (HMGB1), interleukin (IL)-1β, IL-6 and tumour necrosis factor-alpha (TNF-α) were determined using quantitative PCR analyses and immunofluorescent staining. Toll-like receptor 4 (TLR4) and nuclear factor kappa B (NF-κB) activation were examined using western blotting. RESULTS:The CUMS group showed increased serum cortisol and ACTH levels. Pathological changes in the ultrastructure, oxidative stress and inflammatory cytokines in the masseter muscles were also observed. Curcumin treatment (50, 100 mg/kg) ameliorated these changes significantly by varying degrees. Mechanistically, increased levels of phosphorylated NF-κB, toll-like receptor 4 and HMGB1 were observed, which were also ameliorated by curcumin treatment. CONCLUSION:Curcumin can reduce local pathological changes, levels of oxidative stress and inflammatory factors in masseter muscles. Psychological stress activates HMGB1 expression and increases the expression of downstream TLR4 and p-NF-κB, which could be reduced by curcumin. Thus, curcumin might exert anti-inflammatory and antioxidant effects in masseter muscles via the HMGB1/TLR4/NF-κB pathway.

口腔住院医师规范化培训(简称住培)是口腔医学人才储备、建设的基础,口腔急诊教学是住培的重要组成部分,保证口腔急诊的住培效果和质量是医院人才培训工作的重要内容,而良好的师资队伍是住培基地顺利完成口腔急诊住培的关键因素.口腔急诊带教师资培训缺乏规范、指导老师带教缺少热情、教学认识存在偏差、奖惩措施尚不完善是当前口腔急诊住培过程中师资队伍建设存在的主要问题,通过严把带教师资准入条件、提高带教师资职业素养、促进教学团队整体提升、建立奖罚分明具体措施、调整医教工作合理比例、发挥住院医师反馈作用,对提升师资队伍水平、改善口腔急诊住培效果具有重要作用.只有不断提升口腔急诊带教师资素养,方能切实培训出有岗位胜任力的口腔住院医师.

目的 探究Er:YAG激光照射时间对牙本质小管封闭效果的影响.方法 将160个2mm厚牙本质片用0.5mmol/L EDTA去除玷污层以建立牙本质过敏症模型,然后将样本等分为16个组,应用聚焦式照射手具和散焦式照射手具按照2s×1次、2s×2次、2s×3次、2s×4次、4s×1次、6s×1次、8s×1次的照射时间照射牙本质片.照射后用扫描电镜(SEM)观察所有样本的牙本质小管形态,应用Image-Pro Plus 6.0图像分析软件计算牙本质小管的暴露面积和封闭率.结果 电镜扫描可见,对照组的牙本质小管形态完整、均匀开放,Er:YAG激光照射不同时间后牙本质小管口表层均有均匀致密的牙本质熔融层形成.图像分析结果 可见,Er:YAG激光照射后各组牙本质小管的暴露面积均明显小于对照组(P<0.05),牙本质小管封闭率均明显增加(P<0.05).但不同激光手具和照射时间实验组的牙本质小管暴露面积和牙本质小管封闭率比较,差异无统计学意义(P>0.05).结论 适宜的Er:YAG激光照射时间有效封闭牙本质小管后,增加照射时间不会进一步提高牙本质封闭效果,为确保操作的安全性及缩短临床就诊时间,建议结合临床实际减少激光脱敏照射时间.

目的 明确Er∶YAG激光照射能量对牙本质小管的封闭效果影响.方法 将140个牙本质片建立牙本质过敏症模型并等分为14个组,应用聚焦式和散焦式照射手具按照0.3W、0.4W、0.5W、0.6W、0.7W、0.8W Er∶YAG激光照射能量照射牙本质片.扫描电镜(SEM)观察照射后牙本质小管形态,并计算牙本质小管的暴露面积和封闭率.结果 两种手具对照组的牙本质小管形态完整、均匀开放,0.3W组牙本质小管口明显缩小,但仍清晰可见,0.4W～0.6W组牙本质小管口消失,表层形成熔融层,表面均匀平整,0.7W～0.8W组的牙本质小管口明显熔融呈焦灼样;图像分析结果可见,当照射能量为0.3W～0.8W时,两种手具组的牙本质小管暴露面积均明显小于对照组(P＜0.05),封闭率明显大于对照组(P＜0.05),且0.4W～0.6W照射时的牙本质小管暴露面积均明显小于0.3W、0.7W和0.8W组(P＜0.05),封闭率明显大于0.3W、0.7W和0.8W组(P＜0.05).照射能量相同时,两种手具组牙本质小管暴露面积和封闭率比较无统计学差异(P＞0.05).结论 Er∶YAG激光照射有较好的牙本质小关封闭效果,照射能量是影响Er:YAG激光封闭牙本质小管的重要因素.

牙本质磷蛋白(DPP)作为牙本质中非常重要的一种非胶原蛋白,与牙本质的生物矿化、再矿化有着密切关系.仿生矿化是近年来牙体硬组织研究的热门方向,受到化学、物理、生物及材料学等多学科的关注.本文就牙本质磷蛋白的结构、功能、仿生矿化机制、研究体系及牙本质磷蛋白在仿生矿化中的研究进展做一综述.

口腔医学临床实习教学的管理及质量监控一直是临床教学工作的重点和难点.在互联网和信息技术快速发展的情况下,教学流程及教学质量监控的数字化是教学管理信息化发展的必然趋势.利用互联网技术和模块化的管理软件建立临床教学的数字化管理系统,实现对口腔临床综合实习教学各个环节的精确把控,有助于提升临床教学管理水平,提高口腔临床实习教学质量.

一名合格的口腔医生不仅要有良好的专业素质,还应该具备优秀的人文素质.口腔临床实习是口腔医学生岗前人文素质培养的最后一道关口,这一阶段加强学生的人文素质教育,能为将来成为一名医技与医德兼备的口腔医务人员打下坚实的基础.本文阐述了口腔医学生临床实习过程中人文素质教育的必要性,分析了人文素质教育实施的现状,并提出了加强人文素质教育的有效措施,为完善口腔医学生岗前素质教育培训,全面提高口腔医学生综合能力以及医学服务质量提供新的思路.