Validation of a Facial Image Scale to assess child dental anxiety

Summary. Objective. To examine the validity of a scale that uses faces as an indicator of children’s dental anxiety. Setting. Department of Child Dental Health waiting room, Newcastle Dental Hospital. Subjects and methods. 100 children (aged 3–18 years) completed the Facial Image Scale (FIS) and the Venham Picture Test (VPT) in the dental hospital waiting room. Results. A strong correlation (0·7) was found between the two scales, indicating good validity for the FIS. Findings also showed that a small, but significant, number of children are anxious in the dental context. Conclusion. The findings suggest that the FIS is a valid means of assessing child dental anxiety status in a clinical context.     

Porous bovine bone mineral in healing of human extraction sockets: 2. Histochemical observations at 9 months

BACKGROUND: Porous bovine bone mineral (PBBM) has been used in ridge preservation procedures following tooth extractions. The aim of this study was to investigate histochemically tissue sockets grafted with PBBM at 9 months post-extraction. By using different histochemical stainings, characteristics of the newly formed bone; i.e., lamellar/woven ratio at different socket depths, were investigated and the arrangement of bone around the grafted material, as well as the nature of the amorphous organic material found in all specimens, were examined. METHODS: After extraction of 15 single-rooted maxillary teeth from 15 patients, socket sites were grafted with PBBM particles (250 to 1,000 mu). Primary soft tissue closure of the grafted site was established using the rotated split palatal pedicle flap technique. At 9 months, a cylindrical tissue specimen, 2.5 mm in diameter, was trephined from each previously grafted site followed by placement of a screw-shaped implant. Horizontal tissue section cuts, 5 mu wide, were prepared for histological examination. Histochemical staining included alcian blue, periodic-acid Schiff, Mallory trichrome, reticulin, Van Gieson, and picrosirius red (PSR). PSR stained slides were further evaluated morphometrically, using polarized microscopy to determine the amount of lamellar versus woven bone in superficial, mid and deep specimen section cut areas. RESULTS: All staining methods revealed that newly formed bone encircled and adhered to the grafted material in most specimens. Mallory trichrome staining showed osteoblasts present within an osteoid layer, lining the interface zone of PBBM particles and the new osseous tissue. Morphometric evaluation of the PSR stained slides disclosed a constant pattern of increased osseous tissue in a coronal-apical direction. An average of 17.1% osseous tissue with 1:12.9 lamellar/woven bone ratio was calculated in the superficial area. The average bone tissue fraction was 48.3% with a lamellar/woven ratio of 1:3.8 in the mid section area and in the deep area, it increased to 63.9%, with a lamellar/woven ratio average of 1:1.7. Differences between ratios at these sites were statistically significant (P<0.001). An amorphous organic substance was noted in most grafted particles. This material usually attached cell striae and harbored glycoproteins as revealed by periodic-acid Schiff and alcian blue stainings. Mallory trichrome staining showed denatured protein within the decalcified mineral particles; reticulin, Van Gieson stainings, and polarization of PSR stained sections refuted the existence of collagen in the grafted particles. CONCLUSIONS: Cancellous PBBM is a biocompatible filler agent in extraction socket sites and an acceptable graft for edentulous ridge preservation at sites prepared to receive endosseous implants. The osteoconductivity of PBBM was determined based on promoting osseous ingrowth and close integration with the newly generated bone. Grafted particles were not significantly resorbed at 9 months. Further studies are needed to determine the resorbable capability, as well as the nature and significance of the amorphous organic substance of PBBM observed in the grafted particles.     

Prognosis of caries increment with past caries experience variables

This study aimed to select past caries experience variables as caries predictors and to compare their prognostic accuracy with the variables used in a method of caries prognosis developed in a Swiss child population. The data used for the analyses originated from an 8-year longitudinal study starting in 1980 on caries of 7.5-year-old Dutch children. Stepwise logistic regression analyses provided predictor variables. The newly introduced variables D23fi, D(123)i and D23pifi were interchangeable and the most powerful caries predictors. For the sake of uniformity and ease of application, D23fi (number of fissures of the permanent first molar with non-cavitated or cavitated caries lesions) was chosen as the first variable in the logistic regression equations. The gain in accuracy of the second and third predictor variables (number of sound primary molars and the number of buccal and lingual smooth surfaces of the permanent first molar with non-cavitated or cavitated caries) in the regression equations was limited. The D1 condition of surfaces could be omitted from the prediction models. The present forced three-predictor-regression equations for 7.5-, 9.5- and 11.5-year-old children were evaluated to assess their prognostic performance by using the area under the ROC curve as a measure of prognostic quality. For the present regression equations, the area under the ROC curve was 81-87%, which was higher compared to the Swiss regression equations for caries prognosis.     

Effect of occlusal trauma on healing of periapical pathoses: report of two cases

AIM: To present two clinical cases and demonstrate that occlusal trauma may affect healing of periapical pathoses. SUMMARY: Two teeth with periradicular disease did not respond successfully to conventional root canal treatment or endodontic surgery. Occlusal adjustment was finally performed on both cases. After occlusal adjustment, uncomplicated healing and periapical repair occurred in both cases. The findings in these two cases suggest that occlusal trauma may play a role in the healing of periapical pathoses. KEY LEARNING POINTS: Occlusal trauma is positively correlated with changes in periodontal tissues. Although experiments in animals have shown that application of forces to teeth will not induce further periodontal destruction, we believe that some failures of root canal treatment may be due to the presence of occlusal trauma modulating the responses of inflamed periapical tissues or apical pathoses with persistent infection.     

Changes in mechanical properties of poly-l-lactic acid mini-plate under functional load simulating sagittal splitting ramus osteotomy

The purpose of this study was to investigate how the characteristics of a poly-l-lactic acid mini-plate changed with dynamic loading in an environment with hydrolytic degradation. A mandible osteosynthesis model was prepared with specimen poly-l-lactic acid mini-plates to simulate sagittal splitting ramus osteotomy. The model was then subjected to dynamic loading, and changes in specimen shape and surface quality were observed. Specimen bending strength was then measured, and degree of hydrolytic degradation estimated. Neither dynamic loading nor degree of load clearly affected degree of hydrolytic degradation. The specimens maintained their original shape and bending strength for up to 4 weeks with dynamic loading of 40 N or less in an environment with hydrolytic degradation. At 8 weeks, under the same conditions, the specimens showed cracks or fractures, or both, together with a clear decrease in bending strength. The results suggest that dynamic loading causes cracking in a poly-l-lactic acid mini-plate, and that growth of these cracks decreases bending strength over time, leading to fatigue fracture.     

Expression of two drug-metabolizing cytochrome P450-enzymes in human salivary glands

Objective:  The oral cavity is constantly lubricated by saliva and even small amounts of xenobiotics and / or their metabolites in the saliva may affect the oral mucosa. Our aim was therefore to clarify if xenobiotic metabolizing enzymes CYP1A2 and CYP3A4 are expressed in salivary glands.
Methods:  Formalin-fixed paraffin-embedded specimens from parotid (10), submandibular (7) and labial (10) salivary glands were examined immunohistochemically and by in situ hybridization for expression of CYP1A2 and CYP3A4 protein and mRNA.
Results:  CYP1A2 and CYP3A4 protein and mRNA were detected in ductal and seromucous / serous acinar cells in all gland types although to a varying degree and intensity. Mucous acinar cells were positive to a lesser extent.
Conclusion:  The results indicate a xenobiotic metabolizing capability of salivary glands. This may have implications for development of oral mucosal disease as a result of mucosal exposure to metabolites originating from internal sources (blood) as well as from saliva.     

Three-dimensional motion analysis - an exploratory study. Part 1: assessment of facial movement

Authors – Popat H, Richmond S, Playle R, Marshall D, Rosin PL, Cosker D Objectives – To objectively quantify facial movement in response to facial expression and spoken word. Design – Experimental study. Setting – Department of Dental Health and Biological Sciences, University Dental Hospital, Cardiff, UK. Experimental Variable – Facial movement was assessed in response to a standardized smile expression and the utterance ‘puppy’. The sequences were recorded using a non‐invasive, three‐dimensional motion analysis image capture system (3dMDface? Dynamic System) at 48 frames per second. Outcome Variable – To quantify the facial movement, sequential frames of a sequence were aligned to the baseline/reference frame three‐dimensionally using best fit on non‐moveable points in the upper half of the face. Accuracy of the alignment process for each sequence was tested using the percentage of stable points (i.e. within ±0.5 mm) within the upper half of the face. Results – Quantifiable changes in facial topology were seen during both the standardized smile expression and the utterance ‘puppy’. The mean percentage of points (SD) that remained stable within the upper half of the face during the utterance ‘puppy’ was 88.8% (4.7). During the standardized smile expression, there were a much lower percentage of stable points in the upper half of the face with a mean (SD) of 60.9% (3.2). Conclusion – The 3dMDface? Dynamic System allows objective, three‐dimensional, non‐invasive assessment of facial movement. The utterance ‘puppy’ is a more appropriate measure of facial movement when compared with the standardized smile expression.     

Endoscope-assisted reduction of long-standing condylar dislocation

Endoscopy is widely used in the diagnosis and treatment of temporomandibular joint disorders. This paper introduces arthro-endoscopy as a new method of treatment for temporomandibular joint dislocation. As this method is minimally invasive, it is suitable for medically compromised patients who cannot tolerate open surgery.