Extracellular hydrolase activity of the cells of the oral bacterium Streptococcus mutans isolated from man and grown on glucose or xylitol

Cells of Streptococcus mutans were maintained for 18 months in medium containing either glucose or xylitol as the only added carbohydrate. Growth in 0.25 per cent xylitol was retarded by about 60 per cent as compared with the growth in glucose medium. The growth pattern in the presence of xylitol was similar to that obtained when no carbohydrates were added. No uptake of $\text{[}{}^{14}\text{C(U)]-}\text{xylitol}$ was observed with cells maintained for 18 months in xylitol. Extracellular enzyme activities, tested with 10 different $\text{N-}\text{l}\text{-}\text{aminoacyl}\text{-2-}\text{naphthylamines}$, $\text{N-}\text{carbo}\text{-2-}\text{naphthoxy}\text{-}\text{dl}\text{-}\text{phenylalanine}$, casein, azocoll, congocoll and a chromophore collagenase substrate, were significantly higher in the xylitol medium. Isoelectric focusing of proteins from the extracellular medium containing xylitol revealed enzymes hydrolysing $\text{N-}\text{l}\text{-}\text{methionyl}\text{-2-}\text{naphthylamine}$ and casein, not detected in the chromatograms of glucose-containing medium. Xylitol behaved as an inert carbohydrate with respect to the increases in the extracellular proteinase activities, and could be associated with a general increase in protein metabolism upon starvation of a fermentable carbohydrate (glucose). Similar increase in the proteinase activities occurs in whole saliva and dental plaque when xylitol is habitually consumed. Because of their non-specificity, these proteinases could attack salivary proteins and peptides in vivo.     

Dietary factors in the prevention of dental caries: a systematic review

The aim of this study was, systematically, to evaluate the effect of dietary changes in the prevention of dental caries. A search and analysis strategy was followed, as suggested by the Swedish Council on Technology Assessment in Health Care (SBU). The search strategy for articles published in 1966-2003 was performed using electronic databases and reference lists of articles and selected textbooks. Out of 714 articles originally identified, 18 met the inclusion criteria for a randomized or controlled clinical trial--at least 2 years' follow-up and caries increment as a primary endpoint. This included the total or partial substitution of sucrose with sugar substitutes or the addition of protective foods to chewing gum. No study was found evaluating the effect of information designed to reduce sugar intake/frequency as a single preventive measure. It is suggested that the evidence for the use of sorbitol or xylitol in chewing gum, or for the use of invert sugar, is inconclusive. No caries-preventive effect was found from adding calcium phosphate or dicalcium phosphate dihydrate to chewing gums. The review dearly demonstrates the need for well-designed randomized clinical studies with adequate control groups and high compliance.     

Management of spontaneous enophthalmos due to silent sinus syndrome: a case report

Silent sinus syndrome (SSS) is a rare disease exhibiting unilateral enophthalmos and hypoglobus. A 26-year-old white female presented with right side enophthalmos and hypoglobus. There was no history of previous trauma or maxillary sinus diseases. A CT scan showed an opacified right maxillary antrum with decreased volume and downward bowing of the right orbital floor. From clinical and radiological findings the diagnosis SSS was made. Biopsies were collected from the maxillary sinus for the exclusion of malignancy. Two months later orbital floor reconstruction was carried out. Before antrostomy of the affected maxillary sinus, a relative enophthalmos of 4mm was determined. Five days after antrostomy the value reduced to 2.3mm. During the following 2 months the enophthalmos remained constant. At the end of the operation for orbital floor reconstruction it was 0.1mm. Five days after surgery the relative enophthalmos increased to 0.8mm. The value remained constant during the following 3 months. Initial antrostomy of the affected maxillary sinus may lead to a relevant, spontaneous reduction of enophthalmos. After a minimum period of 2 months a re-evaluation should be made, if a reconstruction of the orbital floor is still necessary for the correction of the globe position.     

A Swedish version of the GOHAI index. Psychometric properties and validation

This study investigated a Swedish version of the 12 item General Oral Health Assessment Index (GOHAI). The aim was to validate the translated instrument, and to investigate factors that may influence the GOHAI score. Consecutive samples at eight dental clinics in G?teborg, Sweden were asked to answer the GOHAI, the short form of Oral Health Impact Profile (OHIP-14) and a questionnaire including socio-demographic, general health and oral health questions. 153 patients (50-89 yrs old) out of 237 (65%) returned the questionnaires. The most commonly reported problem (GOHAI) was 'worried or concerned' due to problems related to oral health (48%), followed by 'unhappy with the appearance of teeth, gums, or dentures' (36%) and 'teeth sensitive to hot, cold, or sweets' (33%). The Cronbach's Alpha (0.86) indicated a high degree of internal consistency and homogeneity between items. Item-scale correlations varied between 0.50 and 0.83. Strong relations were found between depressed GOHAI-scores and dental problems (mobile teeth, number of teeth, dentures). The correlation between the GOHAI score and the OHIP-14 was high (-0.83) indicating good construct validity. Also 'perceived general health' and 'satisfaction with life-situation' and dental status were significantly, but less strongly, correlated with the patient's GOHAI score. In a linear regression analysis, age,'perceived general health' and dental status (number of teeth in lower jaw and mobile teeth) were found to have a significant effect on the GOHAI score. Factor analysis of GOHAI indicated a two-factor solution and did not support the theoretical construction reported of the index. The test-re-test reliability was assessed in a separate sample (members of a physical handicap organization, n = 47) and the correlation coefficient for the GOHAI was 0.64. For individual items, the weighted kappa coefficient varied between 0.25 and 0.80. In conclusion, the Swedish version of the GOHAI showed acceptable reliability and validity.     

Subgingival plaque removal in buccal and lingual sites using a novel low abrasive air-polishing powder

AIM OF THE STUDY: This study was aimed at assessing the efficacy of subgingival plaque removal in buccal and lingual sites during supportive periodontal therapy (SPT) using a novel low abrasive air-polishing powder. MATERIAL AND METHODS: In 27 SPT patients, subgingival debridement was performed using the novel air-polishing powder (test) and hand instruments (positive control) in a randomized split mouth design. Before and immediately after treatment, subgingival plaque samples were taken from two teeth with pockets of 3-5 mm depth in both groups. To assess the influence of plaque sampling on the microflora, samples were also taken twice from two untreated teeth (negative control). The mean reduction in total colony forming units (CFU) was assessed by anaerobic culture. The patients' perception of treatment was assessed by a visual analog score (VAS). Therapy and plaque sampling were repeated after a 3-month interval. RESULTS: Test treatment resulted in a significantly greater reduction in mean CFU than positive control treatment (log 1.7+/-0.98 and log 0.61+/-0.79 respectively; p<0.05). Following both treatments, the CFU reduction was significantly greater compared to negative control treatment (log 0.06+/-0.49; p<0.05). In addition, test treatment was perceived as significantly more pleasant than hand instrumentation (p<0.05). CONCLUSION: The novel low abrasive air-polishing powder is superior to curettes in removing subgingival plaque from pockets of 3-5 mm depth in supportive periodontal therapy and offers greater patient comfort.     

Temporomandibular disorders,occlusion, and neck pain in subjects with facial pain: a case-control study

The etiology of facial pain is multifactorial. Based on the results of a questionnaire included in the study of the 1966 Northern Finland Birth Cohort, performed in 1997-98, we found an association of facial pain with subjective symptoms of temporomandibular disorders (TMD), neck pain and with occlusal factors reported by 5,696 subjects. The aim of the present study was to examine these associations clinically. In the year 2000, a new inquiry was sent to the following subjects living in Oulu: 1. all subjects who had reported facial pain in the former questionnaire (n=162) (case group); and 2. to a randomly selected group of nonpain controls (n=200), group matched for gender. Those who reported willingness to participate were invited to a clinical examination. Finally, the total number of subjects was 104, including 52 (10 men, 42 women) cases and 52 (10 men, 42 women) controls. Anamnestic data were collected, and clinical stomatognathic and musculoskeletal examinations were performed, both the clinicians and the subjects being unaware of the case-control status. Anamnestically, stress was the most often reported provoking factor for facial pain. Facial pain associated significantly with reported TMD symptoms and allergies. Based on clinical findings, most of the cases were classified in the myogenous subgroup of TMD. The risk for facial pain was six-fold in subjects with clinically assessed TMD, defined as moderate (DiII) or severe (DiIII) by Helkimo's clinical dysfunction index, almost six-fold in subjects with protrusion interferences and approximately three-fold in subjects with clinically assessed tenderness of distinct fibromyalgia (FM) points in the neck. According to the adjusted logistic regression analyses, TMD had the strongest influence on facial pain, followed by protrusion interferences, anamnestically reported allergies and "other headaches". The present study shows that as well as being connected with TMD, facial pain is associated with pain and muscle tenderness in the neck area.     

Efficiency of the polymer bur SmartPrep compared with conventional tungsten carbide bud bur in dentin caries excavation

SmartPrep is a rotating instrument for dentin caries excavation made from a special polymer. The manufacturer's product information stated that SmartPrep removes carious dentin selectively. This in vitro study compared the efficiency of SmartPrep with conventional tungsten carbide bud burs. Fifty extracted teeth were split in the center of a carious lesion. The 100 specimens were randomly divided into five groups. Five dentists were asked to excavate 10 teeth each: one half with SmartPrep and the corresponding half with conventional bud burs. The time needed for the caries excavation was measured. Subsequently, histological specimens were produced from all cavities and analyzed by light-microscope after Mallory-Azan-staining. The thickness of the remaining caries was measured (< 1 mm or > 1 mm). The time expended was analyzed using the paired t-test. The results were analyzed for the remaining caries and thickness of the carious layer for every tooth, using the non-parametric Wilcoxon test for combined random samples. A binary logistical regression was performed to determine the influence of the three variables (tooth, sections or bur) on the criteria "caries" or "carious layer thickness (> 1 mm)." The average time to excavate a cavity with SmartPrep was 208.1 seconds, and it was 228.32 seconds with conventional bud burs. The difference between the recorded times was not statistically significant (p > 0.05). In 37 of 50 teeth, the number of carious sections was higher in the SmartPrep group than in the bud bur group. In nine teeth, the quantity of carious sections was higher in the bud bur group than in the SmartPrep group. Four teeth showed no difference in the number of carious sections. The results were statistically significantly different (p < 0.001). In 30 teeth, the number of carious sections with a carious layer thicker than 1 mm was higher in the SmartPrep group compared with the bud bur group. In nine teeth, the number of carious sections was higher in the bud bur group than in the SmartPrep group. Eleven teeth showed no difference in thickness of the carious dentin layer. These results were statistically significantly different (p = 0.003). Binary logistical regression showed that only the variable "bur" (bud bur or SmartPrep) influenced the results concerning the criterion "caries" (p < 0.001).     

Head immobilization can impair jaw function

Findings that jaw-opening/-closing relies on both mandibular and head movements suggest that jaw and neck muscles are jointly activated in jaw function. This study tested the hypothesis that rhythmic jaw activities involve an active repositioning of the head, and that head fixation can impair jaw function. Concomitant mandibular and head-neck movements were recorded during rhythmic jaw activities in 12 healthy adults, with and without fixation of the head. In four participants, the movement recording was combined with simultaneous registration of myoelectric activity in jaw and neck muscles. The results showed neck muscle activity during jaw opening with and without head fixation. Notably, head fixation led to reduced mandibular movements and shorter duration of jaw-opening/-closing cycles. The findings suggest recruitment of neck muscles in jaw activities, and that head fixation can impair jaw function. The results underline the jaw and neck neuromuscular relationship in jaw function.     

Specialisation and specialist education in prosthetic dentistry in Europe

This presentation reports on the results of a meeting of prosthodontists from selected European countries. The aim of the meeting was to analyse and promote specialisation and specialist education in Prosthetic Dentistry in Europe. Representatives for Europe were selected from the European Prosthodontic Association (EPA) board, the Education and Research Committee of International College of Prosthodontists (ICP), countries with a legally recognised speciality, countries without a recognised speciality but organised training programmes and countries with neither of these situations. Data about specialisation and specialist training in Prosthodontics in Europe was scrutinised and discussed. The programmes for countries with specialist training had relatively similar content, mostly of three years duration. There was strong agreement that a recognised speciality raises the level of care within the discipline for both specialists and non-specialists. In several of the countries where a speciality had been introduced it had been initiated by pressure from public health planning authorities. The conclusions are that from a professional viewpoint an advancement of the speciality over Europe would develop the discipline, improve oral health planning and quality of patient care. A working group for harmonisation was recommended.