The long-term effect of a composite resin restoration on proximal contact tightness

OBJECTIVE: The aim of this study was to investigate changes in proximal contact tightness up to 6 months after the restorative treatment. MATERIALS AND METHODS: In a randomised clinical trial Class II composite resin restorations were placed in 52 patients. Proximal contact tightness was measured before, directly after, and 6 months after treatment. These data were analysed statistically using linear regression and t-tests. RESULTS: Proximal contacts, that increased in tightness as result of the treatment tend to loose tightness after a 6-months period but remain tighter than before treatment. Proximal contacts, that decreased after treatment hardly change after 6 months. CONCLUSIONS: A change in contact tightness after restorative treatment will not always remain stable over time.     

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目的评价不同漂白方法对氟斑牙漂白的临床效果。方法轻中度氟斑牙患者30例随机分为3组,每组10例60颗牙。分别采用联合漂白、激光漂白、家庭漂白3种方法进行上前牙区漂白,在漂白前、漂白后即刻、漂白后1个月、漂白后1年记录其L＊a＊b＊值,比较3组漂白效果及颜色回复情况。应用统计学分析软件CS10.34对数据进行t’检验。结果 3组漂白后的L＊a＊b＊值与漂白前比较差异均有统计学意义（均P〈0.05）;漂白后1个月,联合组与激光组颜色有所回复（P〈0.05）;漂白后1年,联合组、激光组颜色与漂白后即刻相比有所回复（P〈0.05）,与漂白后1个月相比颜色回复差异无统计学意义（P〉0.05）;家庭组颜色回复差异无统计学意义,但1个月到1年期间颜色变化小于治疗后即刻到1个月的变化（P〈0.05）。结论 3种漂白方案治疗1个疗程都得到相似的美白效果,但短期内也出现漂白牙的颜色回复,家庭漂白颜色相对稳定,诊室漂白收效快,3种治疗方案各有其适应人群。     

Fluoride concentration in supragingival dental plaque after a single intake or habitual consumption of fluoridated milk

The aim of this study was to evaluate the fluoride concentration in supragingival dental plaque after single and repeated intakes of fluoridated milk. The study group consisted of 22 schoolchildren, young adults and adults of both sexes, 8-41 years of age. After a 2-week fluoride depletion period and 3 days of plaque accumulation, 200 ml of fluoridated milk (1g F) was ingested along with a standardized lunch meal. Plaque samples were collected immediately before the intake and after 30, 120 and 240 min. From the adult participants (n = 9), additional samples were colleted after 12 and 18 h. After a fluoride-free washout period of at least 2 weeks, the whole experimental procedure was repeated after 4 consecutive daily intakes of fluoridated milk. The fluoride concentration was determined after micro-diffusion with a fluoride selective electrode. The results showed a statistically significant 3-fold increase of the plaque fluoride levels up to 4 h after the intake. At 12 and 18 h after the intake, the recorded levels went gradually back to baseline. There was no significant difference between the fluoride concentrations in the supragingival plaque after the single intake compared with the repeated intakes. In conclusion, the findings support the suggestion that milk is a suitable vehicle for local fluoride administration into the oral cavity, also when consumed together with a meal.     

Fluoride concentration in supragingival dental plaque after a single intake or habitual consumption of fluoridated milk

The aim of this study was to evaluate the fluoride concentration in supragingival dental plaque after single and repeated intakes of fluoridated milk. The study group consisted of 22 schoolchildren, young adults and adults of both sexes, 8-41 years of age. After a 2-week fluoride depletion period and 3 days of plaque accumulation, 200 ml of fluoridated milk (1g F) was ingested along with a standardized lunch meal. Plaque samples were collected immediately before the intake and after 30, 120 and 240 min. From the adult participants (n = 9) additional samples were collected after 12 and 18 h. After a fluoride-free washout period of at least 2 weeks, the whole experimental procedure was repeated after 4 consecutive daily intakes of fluoridated milk. The fluoride concentration was determined after micro-diffusion with a fluoride selective electrode. The results showed a statistically significant 3-fold increase of the plaque fluoride levels up to 4 h after the intake. At 12 and 18 h after the intake, the recorded levels went gradually back to baseline. There was no significant difference between the fluoride concentrations in the supragingival plaque after the single intake compared with the repeated intakes. In conclusion, the findings support the suggestion that milk is a suitable vehicle for local fluoride administration into the oral cavity, also when consumed together with a meal.     

Hardness of enamel exposed to Coca-Cola and artificial saliva

The purpose of this study was to determine the rate of change in indentation hardness of enamel in permanent teeth exposed to Coca-Cola. In a further experiment, the ability of a commercially available artificial saliva to remineralize enamel treated with Coca-Cola was tested. Ten enamel specimens were randomly chosen to be treated with Coca-Cola (experimental groups) and seven with water (control group). The fluids were applied for 1, 2, 3 h and overnight (15 h), washed off with a few drops of water and the moist enamel indentation hardness tested after each interval. With Coca-Cola treatment, the mean enamel hardness was 92.6% (s.d. = 7.9) of the original baseline hardness after 1 h, 93.25% (s.d. = 10.15) after 2 h, 85.7% (s.d. = 12.03) after 3 h and 80.3% after 15 h. The mean indentation hardness of control specimens treated with water was 108.7% (s.d. = 16.09) of the original hardness after 1 h, 99.09% (s.d. = 18.98) after 2 h, 98.97% (s.d. =11.24) after 3 h and 98.42% (s.d. = 22.78) after 15 h. In a separate experiment, the hardness of 9 enamel specimens was tested, as previously described, before and after treatment with Coca-Cola overnight and again after application of artificial saliva for 3 min. Coca-Cola reduced the mean indentation hardness of enamel in the teeth, but the hardness was partially restored with artificial saliva (Salivart) and increased by 18% from the demineralized enamel hardness.     

二硅酸锂玻璃陶瓷在前牙过小牙修复的临床应用

目的 评价二硅酸锂玻璃陶瓷在前牙过小牙修复中的临床应用。方法 对45例患者的87颗牙使用IPS e.max Press铸瓷贴面修复,于修复完成后1、6、12、24、36个月进行复查,参见改良加利福尼亚牙科协会（CDA）/Ryge标准进行评价,检查包括边缘适合性,瓷表面质地,颜色匹配,牙敏感症状和牙龈健康情况五个方面。结果 1个月复查时,11颗基牙出现牙敏感症状,予脱敏治疗处理后症状明显改善。6个月复查牙龈情况,9颗基牙出现牙龈炎症,经卫生宣教及系统牙周治疗后症状好转。1个月及6个月复查时,所有贴面边缘密合,完整性好,瓷表面质地良好。12个月复查时出现1颗贴面完整脱落,清洁处理后重新粘固未再次发生脱落。24个月复查时,一患者进食过程中前牙误咬硬物发生修复体崩折,牙本质暴露,予重新制作贴面进行修复。观察到36个月时7颗基牙出现不同程度龈退缩。结论 二硅酸锂玻璃陶瓷贴面适用于前牙区过小牙修复,可获得良好的临床效果和远期预后。     

颊脂垫瓣在口腔黏膜下纤维性变术后缺损修复中的应用

目的：研究颊脂垫瓣在口腔黏膜下纤维性变（OSF）切除后组织缺损修复中的应用。方法：10例伴重度张口受限的OSF患者,应用颊脂垫瓣修复切除后遗留的组织缺损,观察颊脂垫瓣的愈合过程及修复效果。结果：术后9例患者张口度均大于3cm,颊脂垫瓣愈合良好,术后1周颊脂垫瓣明显水肿,组织瓣表面有薄层伪膜覆盖,1周后伪膜逐渐消失,2周后伪膜完全消失,2～3周后水肿明显消退,颊脂垫表面逐渐上皮化,6～8周再生的黏膜变得光滑,呈粉红色,类似于正常口腔黏膜。结论：颊脂垫瓣为修复OSF术后缺损提供了一种良好的手术方式,有利于改善张口受限症状。     

Intra-oral fluoride retention 3 minutes after fluoride mouthrinsing in 4- to 5-year-old children: effects of fluoride concentration and rinsing time

This study was undertaken to explore the site-specific retention rate and the possibility of shortening fluoride (F) mouthrinsing time of kindergarten children. Fluoride retention after 10-, 20- and 30-second mouthrinsing was determined in 43 kindergarten children aged 4-5 years. Tooth surfaces were sampled by a paper point method. Fluoride concentrations in the salivary film on tooth surfaces increased from primary molars to primary incisors in the maxilla and decreased from primary molars to primary incisors in the mandible. The fluoride solution reached the primary molars even after a 10-second rinse, but F concentrations were higher after 20 s than after 10 s and significantly higher after 30 s than after 10 s. No significant difference was observed between 20 and 30 s. The average total F retained in the mouth was 0.13 mg after 20 s and 0.17 mg after 30 s. It was concluded that 30-second mouthrinsing, which is used extensively in Japanese kindergartens, can be shortened to 20 s.     

Effect of non-eugenol- and eugenol-containing periodontal dressings on the incidence and severity of pain after periodontal soft tissue surgery

This study examines the incidence and severity of postoperative pain after gingivectomy using one non-eugenol-containing periodontal dressing, Coe-pak (n = 76) and 2 eugenol-containing periodontal dressings, Wondrpak (n = 64) and Nobetec (n = 86). All patients were subjected to gingivectomy using 1 type of local anaesthesia (lidocaine + adrenalin) only and covering the surgical areas with either of the 3 different dressings in a randomized study. Postoperative pain was assessed on 100 mm visual analogue scales over 5 days starting immediately after surgery. No pain was reported by 22.0% of the patients after Coe-pak, 23.4% after Wondrpak and 30.2% after Nobetec. 13.2% of the patients took analgesics after Coe-pak treatment, 3.1% after Wondrpak and 1.2% after Nobetec. Mean pain score after Coe-pak was higher (P less than 0.05) than after Nobetec 2 h after operation until the morning on the 3rd postoperative day. Mean pain score after Coe-pak was higher (P less than 0.05) than after Wondrpak 3 h to 9 h after operation. No statistically significant difference was found between Wondrpak and Nobetec regarding mean pain score.     

Gingival bleeding after Chlorhexidine mouthrinses

Abstract During a clinical trial for evaluating the antiplaque effect of two flavoured chlorhexidine rinses, the observation was made that bleeding after gentle massage of the gingival margin occurred more often after chemical than after mechanical oral hygiene measures. In order to ascertain the validity of this unexpected observation, the same dental students participated in a repetition of the trial 18 months later. The results of the two trials indicate that gingival bleeding after gentle massage of the margin with the side of a periodontal probe actually occurs more frequently after rinsing twice daily with a 0.2% aqueous Chlorhexidine solution for 1 week than after meticulous mechanical oral hygiene measures during an equally long time period. The average frequency of bleeding, in per cent of all examined gingival units, ranged from. 1.3% after mechanical cleaning of the teeth to 5.4% after rinsing with Chlorhexidine for 1 week. Neither the frequency of bleeding nor the difference between mechanical and chemical plaque control were considered to be of clinical significance. Further microbiological and histological studies are being conducted in an attempt to clarify the reason for the observed bleeding tendency.     

Predictive value of clinical and microbiological parameters for the treatment outcome of scaling and root planing

OBJECTIVES: To compare the clinical and microbiological outcome of non-surgical periodontal therapy after 6 months with data obtained after hygienic phase or 6 weeks after completion of non-surgical therapy, in order to evaluate the value of clinical and microbiological parameters to predict treatment success. MATERIAL AND METHODS: Clinical and microbiological data were available from 271 sites in 10 systemically healthy non-smokers with moderate-to-advanced chronic periodontal disease (24-32 sites per individual). Subgingival plaque samples were tested for the presence of Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans, Tannerella forsythensis and Treponema denticola using RNA probes. RESULTS: Stepwise multiple linear regression analysis revealed a significant impact of the number of sites with visible plaque index >1 after hygienic phase on the bleeding tendency of a subject at month 6 (p<0.01). Furthermore, an association could be demonstrated between the number of residual pockets (PD>3 mm) 6 months after therapy and the number of bleeding sites and suppurating sites after hygienic phase (p=0.016). Six weeks after therapy, the mean total bacterial loads had a significant impact on the bleeding tendency of a subject at month 6 (p<0.01). Although the average numbers of sites with persisting P. gingivalis, A. actinomycetemcomitans, T. forsythensis and T. denticola seemed to be very similar 6 weeks and 6 months after therapy, large variations were noted between subjects, and therefore the microbiological status of a subject at week 6 could not predict the status at month 6. CONCLUSIONS: The present study showed a limited potential of microbiological tests, performed after hygienic phase or shortly after non-surgical periodontal therapy, to predict the clinical outcome 6 months later, but confirmed the importance of an establishment of perfect oral hygiene before non-surgical therapy.     

Tooth contacts and stability before and after occlusal adjustment.

A study was undertaken to analyze the possible relationship between the number and type of tooth contacts before, immediately after and 16 weeks after occlusal adjustment and their influence upon occlusal stability. The data collected from 10 adult subjects who required an occlusal adjustment indicated the following: 1. Six of the ten subjects had no clinically perceptible "slide from centric relation" 6 weeks after occlusal adjustment, and the number of teeth and number of contacts were virtually the same immediately after 6 weeks after occlusal adjustment. 2. The remaining four subjects, whose occlusions had relapsed after adjustment, had one dental arch that included a missing tooth. It would seem that dental arches interrupted with extraction spaces do not remain stable with occlusal adjustment alone. 3. The type of tooth contacts that are the most stable are those of a cup against a flat plane (e.g., bottom of a fossa or marginal ridge) or those of a combination of a cup against a flat plane and one or more inclined planes.     

Morbidity after temporomandibular joint arthrography is lower than after removal of lower third molars

The morbidity after temporomandibular joint arthrography was studied as the amount of pain, use of pain medicine, and disturbed sleep and was compared with the morbidity after removal of lower third molars. The morbidity was substantially higher after surgery than after arthrography. It was concluded that the morbidity after arthrography can be kept at a low level and that it should not restrict the indications for this examination.     

Shoulder complaints after nerve sparing neck dissections

The purpose of the study was to analyse the prevalence of shoulder complaints after nerve sparing neck dissection at least 1 year after surgery, and to analyse the influence of radiation therapy on shoulder complaints. Patients were interviewed for shoulder complaints, and patients filled out the shoulder disability questionnaire to evaluate shoulder disability in daily activities. In total 137 patients; 51 after modified radical neck dissection (MRND), 21 after postero-lateral neck dissection (PLND), and 65 after supraomohyoid neck dissection (SOHND) were analysed. After MRND 33.3% of the patients experienced shoulder complaints, after PLND 66.7%, and after SOHND 20% of the patients experienced shoulder complaints. Type of neck dissection was significantly (P < 0.001) related to shoulder complaints. Outcome on the shoulder disability questionnaire also showed a significant (P < 0.01) difference in outcome for type of neck dissection. The prevalence of shoulder complaints after SOHND are low, and reduce disability in daily activities. Radiation therapy does not have a significant effect on shoulder complaints and disability.     

Aspiration in intra-ligamental anaesthesia of lower first molar teeth: a pilot study

Aims: This pilot prospective, randomised, crossover study of positive aspiration frequency in intra-ligamental anaesthesia (ILA) was conducted with the following aims: (1) to determine the frequency of positive aspiration of blood after the administration of ILA at lower first molars, and (2) to evaluate the depth of the pulpal anaesthesia of lower first molars after positive or negative aspiration of blood, using electro-testing. Methods: Intra-ligamental anaesthesia with 4% articaine with epinephrine was administered to the lower first molars of 36 dental student participants. Pulpal analgesia of these 36 molars (17 left and 19 right) was obtained after 114 intra-ligamental insertions, with 3.2 insertions on average, with the help of a computer syringe. The depth of pulpal analgesia after each insertion administration was assessed with electro-testing. Results: A total of 114 intra-ligamental needle insertions were administered, of which 44 led to pulpal analgesia. After up to five administrations of ILA, all 36 molars achieved pulpal analgesia. In 34 of 36 (94.4%) subjects, ILA was accompanied by a positive aspiration test (AT). In the other two cases, successful but slow onset pulpal analgesia was obtained after five intra-ligamental needle insertions but with negative ATs. Conclusions: For the first time, the aspiration of blood after the administration of ILA has been studied. The frequency of positive aspiration of blood and successful pulpal analgesia was 94%. There was a very strong association between positive aspiration of blood after ILA and good pulpal analgesia. When there was negative aspiration of blood after the administration of an ILA, in rare cases pulpal analgesia developed after a delay of 3-5 minutes.     

Bone resorption after maxillary reconstruction with the vascularized free iliac flap

The aim of this study was to evaluate the resorption of the iliac bone after maxillary reconstruction with a vascularized free iliac flap. Twenty-seven patients with maxillary defects who underwent maxillary reconstruction with the vascularized free iliac flap between January 2017 and January 2021 were included. Computed tomography (CT) images taken at 1 week, approximately 6 months, and 1 year after the surgery were used for evaluation. The total iliac bone thickness and height, cortical bone thickness, and cancellous bone density were measured in the CT images. Compared with 1 week after the surgery, the total thickness and height of the iliac bone were reduced significantly 1 year after the surgery, and the cortical bone thickness and cancellous bone density were reduced significantly at 6 months and 1 year after the surgery. Compared with 6 months after the surgery, cancellous bone density was reduced significantly 1 year after the surgery. In conclusion, during the first year after maxillary reconstruction with a vascularized free iliac flap, there was significant resorption of iliac bone, including the total iliac bone thickness and height, the cortical bone thickness, and the cancellous bone density.     

Structural and biochemical modifications in parotid gland induced by fasting

Structural, ultrastructural and biochemical modifications produced by fasting in the parotid gland of guinea pig, were studied. The highest storage of secretory granules was found in the apical cytoplasm after a 12 hour fasting period. The curve of soluble proteins showed that the highest storage of proteins in the parenchyma took place after a 10/12 hour fasting period. Amylase activity reached its highest point after a 10 hour fasting period. We suggest that granules stored in cellular cytoplasm after a 12 hour fasting period would have completed their maturation cycle.     

The influence of mandibular advancement surgery on oral function in retrognathic patients: a 5-year follow-up study.

PURPOSE: Previous studies have shown that patients with mandibular retrognathism who were scheduled for orthognathic surgery have a lower maximum bite force and an impaired chewing performance. Surgical correction of this deformity is supposed to lead to an improvement of these oral functions. One year after surgery, no significant changes could be shown in these patients. However, a longer follow-up might demonstrate an improvement after all. PATIENTS AND METHODS: Maximum bite force and chewing performance were determined in 12 patients with a mandibular retrognathism before mandibular advancement surgery and at least 5 years after surgery. Chewing performance (median particle size) was determined with a sieving method after chewing 15 strokes on an artificial test food. Maximum bite force was recorded bilaterally at the level of the first molars. RESULTS: Five years after surgery, chewing performance was improved, especially in patients with a poor performance before treatment. An increase of the maximum bite force could not be shown. CONCLUSION: Surgical correction of mandibular retrognathism had a positive effect on oral function 5 years after surgery, although it could not be detected 1 year after surgery. However, the function of the masticatory system was still impaired when compared with controls.     

One- and 3-minute plaque removal by a battery-powered versus a manual toothbrush

BACKGROUND: A new battery-powered toothbrush with a fundamentally different design than other powered toothbrushes has recently been introduced. The new toothbrush has a powered oscillating round head and a second powered head that translates back and forth. This study compared the plaque removal efficacy of a manual toothbrush to this new powered toothbrush. METHODS: This randomized, controlled, examiner-masked, four-period cross-over study examined plaque removal with the two toothbrushes following a single use in 40 subjects. Plaque was scored before brushing and after 1 and 3 minutes of brushing using the Turesky modification of the Quigley-Hein index. RESULTS: Baseline plaque scores were 2.98 prior to using the powered toothbrush and 2.99 prior to using the manual toothbrush. The powered toothbrush delivered a covariance-adjusted mean plaque score change from baseline of 0.61 after 1 minute of brushing and 0.93 after 3 minutes of brushing. The adjusted mean changes for the manual toothbrush were 0.43 and 0.62, respectively. The differences between treatment groups were statistically significant (P < 0.001) after both 1 and 3 minutes of brushing. The powered toothbrush had, on average, 42.1% and 49.6% greater plaque removal scores after 1 minute and 3 minutes of brushing, respectively. Both toothbrushes had statistically significantly greater plaque removal scores after 3 minutes than after 1 minute of brushing (P < 0.001). Plaque removal scores for each toothbrush after 3 minutes of brushing were about 50% higher than the scores after 1 minute of brushing. CONCLUSIONS: The powered toothbrush delivered statistically significantly superior plaque removal after both 1 and 3 minutes of brushing compared to the manual toothbrush. Both toothbrushes showed statistically significantly greater plaque removal following 3 minutes of brushing than following 1 minute of brushing, and the difference between the toothbrushes was greater following 3 minutes of brushing than following 1 minute of brushing.     

Functional outcomes with dental prosthesis following simultaneous mandibulectomy and mandibular bone reconstruction

PurposeThis study sought to ascertain masticatory outcomes in patients who underwent mandibulectomy or hemimandibulectomy together with mandibular bone reconstruction to allow for placement of a removable dental prosthesis.MethodsPerioperative changes in masticatory performance, masticatory ability for solids, and patients’ subjective satisfaction were evaluated for 101 patients who had mandibulectomy immediately followed by bone reconstruction. Differences in masticatory performance and masticatory ability for solids after surgery were determined according to occlusal support after surgery and whether the patient was wearing a removable dental prosthesis or not. Occlusal support areas were classified according to Eichner's classification.ResultsPreoperative Eichner's class A patients had no experience of wearing a dental prosthesis before surgery and after surgery did not want one. Their masticatory performance was better than that of patients who wanted a dental prosthesis after surgery. Retrospective analysis of postoperative Class B and C patients revealed that masticatory performance was lower in those who wanted a dental prosthesis than in those who did not want one. When patients wore a dental prosthesis after surgery, masticatory performance was markedly improved over not wearing it. All patients’ subjective satisfaction was significantly improved after surgery.ConclusionsIncreasing the number of occlusal support areas by wearing a removable dental prosthesis after simultaneous mandibulectomy or hemimandibulectomy and mandibular bone reconstruction may improve masticatory functions. Those professional involved in the rehabilitation for the mandibular defect should be mindful that masticatory functions after such surgeries were affected by the masticatory functions before surgery and the number of occlusal support areas after surgery.