Dental findings in Lowe syndrome

This paper presents the dental findings of a child with the oculocerebrorenal syndrome of Lowe. The genetic abnormality in this condition results in an inborn error of inositol phosphate metabolism. Renal tubular dysfunction leads to metabolic acidosis and phosphaturia. At 4 years, generalised mobility of all primary teeth was noted. It is postulated that a defective inositol phosphate metabolism was responsible for the periodontal pathology found in this case. This is in direct contrast with previous reports of prolonged retention of primary teeth in children with this condition. Histology of extracted primary incisors demonstrated enlarged pulp chambers and mildly dysplastic dentin formation. This is consistent with a chronic subrachitic state, a known feature of Lowe syndrome, but no prominent interglobular dentin was present.     

Congruence between self-reported and actually provided prosthodontic services among Swedish dentists

The purpose of this study, comprising two parts, was to investigate the congruence between answers given by general dentists in questionnaires concerning prosthodontic services and the recorded information on the services actually performed by each dentist. In Part I it is investigated whether questionnaire reports of weekly working hours devoted to prosthodontics can be used as indicators of actual prosthodontic production. Part II deals with the dentists' self-reported numbers of single crowns, fixed partial dentures (FPDs), and removable dentures. These reported services are compared with the services actually provided. Part I: A regression analysis indicates a lacking precision for the individual dentist, indicated by a relatively low explained variance (R2 = 0.20). However, a highly significant association is seen between the two production measures (P = 0.000). Part II: The congruence between stated and actually provided services is higher for single crowns and removable dentures than for FPDs. Bivariate regression models are statistically significant for all three services. In Part II, the reported weekly working hours used for prosthodontics covaries significantly with prosthodontic production, but the association is not as strong as in Part I. Although the precision in both Part I and Part II is low for the individual dentist, the questionnaire measure is found to be useful as an indicator in a population of dentists. It is concluded that the questionnaire data can be used as reasonably valid expressions of prosthodontic activity in population-oriented analyses among general dentists.     

牙源性角化囊肿上皮细胞增殖动力学初步研究

目的探讨角化囊肿上皮细胞增殖特性,进一步了解角化囊肿的生物学行为,为临床治疗和预防复发提供一定的依据。方法采用增殖细胞核抗原（ｐｒｏｌｉｆｅｒａｔｉｎｇｃｅｌｎｕｃｌｅａｒａｎｔｉｇｅｎ,ＰＣＮＡ）免疫组化法和细胞核ＤＮＡ含量分析,对牙源性角化囊肿、根尖囊肿、含牙囊肿和造釉细胞瘤上皮细胞进行对比研究。结果角化囊肿上皮细胞增殖活跃,与造釉细胞瘤相似。提示角化囊肿生物学特性为上皮细胞主动生长,而非被动性膨胀生长。结论角化囊肿可视为具有侵袭性生长的良性肿瘤,提出命名为“牙源性角化囊性瘤”更能反应其生物学特性     

Sedation in pediatric dentistry: a practical assessment procedure

An assessment model for evaluating sedation in pediatric dental patients has been described. The model in whole or in part can be a valuable asset in drug trials and clinical evaluations. The unique characteristics of this model include: assessments are easily and quickly carried out without interruption of normal patient care; the criteria for sedation behavior can be standardized and are clinically relevant; a determination of the level of consciousness using an airway obstruction maneuver permits an assessment of safety; and the reliability of the observer ratings is extremely high, thereby avoiding the necessity of specially trained personnel. Using the assessment procedure, a placebo-controlled, double-blind clinical trial of various doses of chloral hydrate with and without N2O was performed. The results indicate that: children receiving the placebo treatment behaved favorably for at least 46% of the ratings; the 20 mg/kg and 40 mg/kg chloral hydrate groups showed little or no improvement when compared with the placebo group; the group receiving 60 mg/kg chloral hydrate had as much as a 33% improvement in behavior as compared with placebo; and with the addition of 40% N2O/60% O2 to 60 mg/kg chloral hydrate premedication, four of 15 children (27%) were unable to maintain a patent airway when intentionally obstructed.     

Use of orally administered diazepam in the reduction of dental anxiety

A double-blind randomized clinical trial of the effectiveness of orally administered diazepam in reducing dental anxiety was conducted. Forty-one subjects were assigned to a diazepam or placebo group and tested, using the Dental Fear Survey and State-Trait Anxiety Inventory. Diazepam was effective in reducing anxiety scores but not dental fear scores.     

Effect of tongue reduction on the orthodontic and surgical treatment of dysgnathia.

The results of reduction of tongue size in connection with orthodontic and surgical correction of prognathic anomalies of the jaws are presented. It is shown that reduction of the tongue size combined with orthodontic treatment arrests of tendency to prognathic growth when it is performed early. The results further indicate that the effect of prophylactic reduction of tongue size to check relapse following surgical correction of prognathism or open bite can only be confirmed in cases of genuine macroglossia. Since there was only one relapse in our cases without reduction of tongue size, the indication for preoperative prophylactic reduction of the tongue is limited. Personal results and experience have been compared with the findings published in the current literature.     

Electron immunoperoxidase stainings in sections of unfixed pure cultures of Streptococcus mutans

Unfixed as well as glutaraldehyde-fixed pelleted cells from pure cultures of Streptococcus mutans subspecies sobrinus (B13) were embedded in glycolmethacrylate. Ultrathin were sections immunoperoxidase labelled with rabbit anti-S. mutans sobrinus gamma-globulin. It was found that unfixed specimens became labelled as precisely and as distinctly as did the fixed specimens. All controls were negative.     

The progress of the periodontal syndrome in the rice rat

Several morphometric and cellular parameters were studied in the rice rat ( Oryzomys palustris ). When fed a soft, high carbohydrate diet, a severe periodontal disease occurred, with significant alterations in the morphometric and cellular endpoints observed. Weaned animals were placed on a high carbohydrate diet for periods of 6, 12 or 18 weeks. There was a linear, rapid loss of bone by 18 weeks, approaching a 75 % loss of original bone. Vascular spaces decreased as the remaining connective tissue became fibrotic in character. The percentage of the interdental test site which was destroyed by periodontal disease increased dramatically over the time of the experiment. The numbers of fibroblasts per mm of bone surface increased slightly at the 18 week period; osteoblasts were unchanged at any period. The numbers of osteoclast nuclei rose dramatically by 12 weeks, and these cell nuclei remained at increased levels at 18 weeks. Also, the numbers of inflammatory cells residing at the bone surface increased greatly by 18 weeks time. Finally, the numbers of ³H-TdR labeled periodontal ligament (PDL) fibroblasts increased significantly at both 12 and 18 weeks time. These cellular changes and their relation to the bone loss due to periodontal disease are discussed.