Occlusion and Temporomandibular Function among Subjects with Mandibular Distal Extension Removable Partial Dentures

Objective. To quantify effects on occlusion and temporomandibular function of mandibular distal extension removable partial dentures in shortened dental arches. Methods. Subjects wearing mandibular extension removable partial dentures (n = 25) were compared with subjects with shortened dental arches without extension (n = 74) and with subjects who had worn a mandibular extension removable partial denture in the past (n = 19). Subjects with complete dentitions (n = 72) were controls. Data were collected at baseline and at 3-, 6-, and 9-year observations. Results. Occlusal activity in terms of reported awareness of bruxism and occlusal tooth wear of lower anterior teeth did not differ significantly between the groups. In contrast, occlusal tooth wear of premolars in shortened dental arches with or without extension dentures was significantly higher than in the controls. Differences amongst groups with respect to signs and symptoms related to temporomandibular disorders were not found. Occlusal support of the dentures did not influence anterior spatial relationship. Occlusal contacts of the denture teeth decreased from 70% for second premolars via 50% for first molars, to 30% for second molars. Conclusions. Mandibular distal extension removable partial dentures in moderate shortened dental arches had no effects on occlusion and temporomandibular function

Contemporary operative caries management:consensus recommendations on minimally invasive caries removal

The International Caries Consensus Collaboration (ICCC) presented recommendations on terminology, on carious tissue removal and on managing cavitated carious lesions. It identified 'dental caries' as the name of the disease that dentists should manage, and the importance of controlling the activity of existing cavitated lesions to preserve hard tissues, maintain pulp sensibility and retain functional teeth in the long term. The ICCC recommended the level of hardness (soft, leathery, firm, and hard dentine) as the criterion for determining the clinical consequences of the disease and defined new strategies for carious tissue removal: 1) Selective removal of carious tissue - including selective removal to soft dentine and selective removal to firm dentine; 2) stepwise removal - including stage 1, selective removal to soft dentine, and stage 2, selective removal to firm dentine 6 to 12 months later; and 3) non-selective removal to hard dentine - formerly known as complete caries removal (a traditional approach no longer recommended). Adoption of these terms will facilitate improved understanding and communication among researchers, within dental educators and the wider clinical dentistry community. Controlling the disease in cavitated carious lesions should be attempted using methods which are aimed at biofilm removal or control first. Only when cavitated carious dentine lesions are either non-cleansable or can no longer be sealed, are restorative interventions indicated. Carious tissue is removed purely to create conditions for long-lasting restorations. Bacterially contaminated or demineralised tissues close to the pulp do not need to be removed. The evidence and, therefore these recommendations, supports minimally invasive carious lesion management, delaying entry to, and slowing down, the destructive restorative cycle by preserving tooth tissue, maintaining pulp sensibility and retaining the functional tooth-restoration complex long-term

Review of experimental methods to determine spontaneous combustion susceptibility of coal – Indian context

This paper presents a critical review of the different techniques developed to investigate the susceptibility of coal to spontaneous combustion and fire. These methods may be sub-classified into the two following areas: (1) Basic coal characterisation studies (chemical constituents) and their influence on spontaneous combustion susceptibility. (2) Test methods to assess the susceptibility of a coal sample to spontaneous combustion. This is followed by a critical literature review that summarises previous research with special emphasis given to Indian coals

TiF4 and NaF varnishes as anti-erosive agents on enamel and dentin erosion progression in vitro

Objective This study assessed the effect of fluoride varnishes on the progression of tooth erosion in vitro. Material and Methods: Forty-eight enamel and 60 root dentin samples were previously demineralized (0.1% citric acid, pH 2.5, 30 min), leading to a baseline and erosive wear of 12.9 and 11.4 µm, respectively. The samples were randomly treated (6 h) with a 4% TiF4 varnish (2.45%F-, pH 1.0), a 5.42% NaF varnish (2.45%F-, pH 5.0), a placebo varnish and no varnish (control). The samples were then subjected to erosive pH cycles (4x90 s/day in 0.1% citric acid, intercalated with artificial saliva) for 5 days. The increment of the erosive tooth wear was calculated. In the case of dentin, this final measurement was done with and without the demineralized organic matrix (DOM). Enamel and dentin data were analyzed using ANOVA/Tukey’s and Kruskal-Wallis/Dunn tests, respectively (p<0.05). Results The TiF4 (mean±s.d: 1.5±1.1 µm) and NaF (2.1±1.7 µm) varnishes significantly reduced enamel wear progression compared to the placebo varnish (3.9±1.1 µm) and control (4.5±0.9 µm). The same differences were found for dentin in the presence and absence of the DOM, respectively: TiF4 (average: 0.97/1.87 µm), NaF (1.03/2.13 µm), placebo varnish (3.53/4.47 µm) and control (3.53/4.36 µm). Conclusion The TiF4 and NaF varnishes were equally effective in reducing the progression of tooth erosion in vitro

Fine motor assessment in chronic wrist pain: the role of adapted motor control

To show whether a difference in fine motor control exists between patients with chronic, undiagnosed wrist pain (CUWP) and healthy controls. Furthermore, a method to assess fine motor function of the wrist is evaluated. A case-control study. The Academic Medical Center in Amsterdam, the Netherlands. Twenty-seven CUWP patients were compared with 50 healthy control subjects. Subjects performed horizontal stroke patterns on a digital writing tablet connected to a computer. The control subjects were tested twice to obtain test-retest reliability. A visual analogue scale was used to assess subjective pain. Fluency of movement and average velocity were measured. Intraclass correlation, ANOVA repeated measures statistics and Pearson correlation were calculated. There is a significant difference in fluency of motion between patients and controls, possibly due to a disturbed motor control, since there is no relationship between pain and test score, nor do CUWP patients have any abnormality in the wrist that can explain the disturbance in motor function. The test method is reliable (ICC = 0.78) and valid. The disturbed fine motor control in CUWP patients is suggested to maintain chronic wrist pain through 'strain injury, causing' pain evasive adaptation of the motor control system. This might lead to new perspectives regarding treatment of CUWP patient

Viability of talus osteochondral defect cartilage for chondrocyte harvesting: results of 151 patients.

BACKGROUND: Large talar cartilage defects can be treated with either autologous chondrocyte implantation or matrix autologous chondrocyte implantation. Both techniques depend on successful harvesting of the chondrocytes. In the past, they have come from the ipsilateral knee, which has been associated with donor site morbidity. We hypothesized that damaged cartilage from the talus can be used as a reliable source for chondrocyte cell harvesting in preparation for possible matrix-induced autologous chondrocyte implantation (MACI). METHODS: Chondrocytes were harvested from the injured talar cartilage during ankle arthroscopy and sent to a cell laboratory, measured for initial biopsy weight, cultured for 4 to 6 weeks, and then analyzed for viability. A total of 151 patients were analyzed. RESULTS: The average biopsy initial weight was 187.1 mg. The average number of cells was 3.13 7 10(5). The viability of the chondrocytes provided by the manufacturer averaged 92.3% (range, 33%-100%). CONCLUSIONS: Chondrocytes harvested from the damaged talar articular cartilage were functional and proliferated with an average viability of 92%. CLINICAL RELEVANCE: This technique may provide a useful source of chondrocytes if needed for a future cell-based regenerative procedure such as MACI while eliminating the need to harvest chondrocytes from the knee or other intact areas of cartilage on the talus. LEVEL OF EVIDENCE: Level IV, case series

Movement patterns of the upper extremity and trunk before and after corrective surgery of impaired forearm rotation in patients with cerebral palsy

The effect of surgical correction of impaired forearm rotation on associated body movement patterns was studied prospectively by comparison of preoperative and postoperative three-dimensional video analysis of the upper extremity and trunk in eight male and two female patients with hemiplegic cerebral palsy (CP; mean age 16y 2mo [SD 4y 11mo]; range 11-27y). A customized parameter, 'extrinsic forearm rotation', was used to quantify associated movements supplementing forearm rotation. After surgical correction of the pronation deformity, active forearm supination during a functional reaching task had improved by a mean of 37 degrees in combination with significantly decreased extrinsic forearm rotation by a mean of 13 degrees . In addition, an average loss of 16 degrees of active pronation in combination with increased extrinsic forearm rotation (mean 8 degrees ) was observed. On the basis of these results we conclude that successful surgical correction of a pronation deformity in patients with CP directly affects related movement patterns of the upper extremity and trun