Impact of operators' experience and patients' age on the success of nitrous oxide sedation for dental treatment in children.

AIM: To evaluate the success rates and potential influencing factors of nitrous oxide sedation for dental treatment in a specialised paediatric dental service. MATERIALS: Medical records of all children treated under nitrous oxide sedation in a specialised pedodontics clinic between 2012 and 2017 were analysed retrospectively for parameters such as age of the patient, experience and change of operating dentists, treatment procedure and success or failure regarding the sedation and treatment. CONCLUSION: Given the high overall success rate of over 90%, nitrous oxide sedation can be a highly effective treatment option for performing dental treatment in pre-cooperative and/or anxious children and adolescents. With age of the children and experience of the dentist, success rates increased.

Self-reported chewing side preference and its associations with occlusal, temporomandibular and prosthodontic factors: results from the population-based Study of Health in Pomerania (SHIP-0).

This study investigated the prevalence of a preferred chewing side (PCS) and associations between a PCS and signs of temporomandibular disorders (TMD), antagonist contact and prosthetic restoration. A population representative sample of 4086 adults of the cross-sectional epidemiologic 'Study of Health in Pomerania' (SHIP-0) (age range 20-80 years, female 50.2%) was divided in two groups by the presence or absence of a PCS. PCS was evaluated by a questionnaire. Chi-squared tests and multiple logistic regression were used to determine the impact of the relation between a PCS and signs and symptoms of TMD as well as dental factors. The prevalence of a PCS was 45.4%. Women between 40 and 69 years reported more frequently a PCS. There was a preference for the right side (64%). The following independent variables were significantly associated with a PCS: subjective unilateral pain in the temporomandibular joint (TMJ), odds ratio (OR) 2.4; subjective unilateral joint clicking, OR 1.7; unilateral TMJ/muscle pain on palpation, OR 1.6/OR 1.3; loss of one supporting zone (Eichner-Classification), OR 1.9; loss of both supporting zones on one side, OR 2.2, one supporting zone left, OR 1.4; presence of a removable partial denture, OR 1.6; presence of an attachment restoration, OR 1.5. A PCS was found in almost half the study population and was associated with unilateral signs of TMD, most of all TMJ pain and asymmetrical loss of antagonist contact. Despite replacement of lost teeth not all restorations seemed to support bilateral mastication.

Influence of Age and Tooth Loss on Masticatory Muscles Characteristics: A Population Based MR Imaging Study.

BACKGROUND: Aging is associated with a decline in masticatory muscles mass and performance. The present study aims to examine the differences in the cross-sectional areas of the masseter, medial and lateral pterygoid muscles in relation to age and the present dental status in a population-based magnetic resonance imaging study. METHODS: This cross sectional study involved 747 subjects aged between 30-89 years (344 male, 403 female) who underwent both a whole body MRI and a full oral examination. The cross-sectional areas of the masseter, medial and lateral pterygoid muscles were measured from MRI images using the software Osirix. Dental and prosthetic status data from the oral examination were classified according to Eichner index. The method of generalized least squares, also called growth curve model, was used to examine the associations between the cross-sectional areas, age and tooth status. RESULTS: The cross-sectional area of the lateral pterygoid muscle decreased substantially with age in women but did not depend on age in men. The medial pterygoid muscle depended on age but an effect modification by gender was uncertain. Masseter muscle was weakly associated with age but strongly associated with the number of teeth in both genders. CONCLUSIONS: Our findings suggest that age has a heterogeneous effect on masticatory muscles. This indicates that age related changes to the masticatory muscles are muscle specific and are not consistent between the different muscles.

Comparative clinical investigation of horizontal condylar inclination using the JMA electronic recording system and a protrusive wax record for setting articulators.

PURPOSE: The rationale for recording protrusive mandibular movement is to accurately adjust an articulator. Techniques to record condylar inclination include extraoral tracings and intraoral recording materials. This study compared horizontal condylar inclination angles (HCI) recorded with a protrusive interocclusal record and an electronic pantographic device, the Jaw Motion Analyzer (JMA). MATERIALS AND METHODS: Twenty-three volunteers (12 females; 11 males; mean age 46.7 years) were selected for this study. First, a protrusive interocclusal wax record after 5 mm protrusive movement was taken from the volunteers and the HCI angles were determined after mounting the volunteers' casts in 2 different articulators (SAM 2; Reference SL). Second, kinematic hinge axis and the HCIs were recorded after 5 mm protrusive movement from protrusive jaw tracks recorded with the JMA. ICC and mean values for HCI were used for statistical analysis. Mean differences of HCI between the measuring methods were compared by Bland Altman Plots. RESULTS: The agreement of the HCI between the articulators determined by the protrusive record was good. The mean HCI value recorded with the JMA was significantly higher compared to the values of the protrusive wax records. There was no agreement found between the different methods for calculating the HCI. CONCLUSION: A large variance in articulator settings obtained by interocclusal records is often found. The JMA was found reliable and valid for measuring HCI values. Within the limitations of this study, the use of a pantographic device should be considered for individually adjusting articulators rather than the use of protrusive records.

Magnesium deficiency is associated with periodontal disease.

In the multifactorial pathogenesis of periodontitis, there are still unknown factors influencing the outcome of the disease. An association between magnesium and periodontitis has been suggested by preliminary studies. However, relevant clinical data are lacking. We investigated the association between magnesium status and periodontal health in a population-based analysis. We conducted a cross-sectional epidemiological investigation involving 4290 subjects aged 20-80 yrs. We recorded periodontal risk factors and determined concentrations of serum magnesium and calcium, relating them to periodontal parameters. In a matched-pair study, 60 subjects using oral magnesium-containing drugs and 120 without were compared. In subjects aged 40 yrs and older, increased serum Mg/Ca was significantly associated with reduced probing depth (p<0.001), less attachment loss (p=0.006), and a higher number of remaining teeth (p=0.005). Subjects taking Mg drugs showed less attachment loss (p<0.01) and more remaining teeth than did their matched counterparts. These results suggest that nutritional magnesium supplementation may improve periodontal health.

The interleukin-1 polymorphism, smoking, and the risk of periodontal disease in the population-based SHIP study.

Several studies have shown a role for interleukin-1 gene cluster polymorphisms in the risk assessment for periodontal diseases. In the Study of Health in Pomerania (SHIP), 3148 subjects were randomly selected from the population and assessed for a broad range of diseases and environmental/behavioral risk factors. From the complete study group in the age 40 to 60 years, N = 1085 subjects were genotyped for the interleukin-1 genotype composite polymorphism in relation to periodontal parameters. The study objective was to elucidate the gene-environment interaction between the risk factors smoking and IL-1 polymorphism. An increased risk of periodontal disease was found for IL-1 genotype-positive smokers: odds ratio adjusted for age, sex, education, and plaque OR = 2.50 (95% C.I. 1.21 to 5.13; p = 0.013). This was not the case with subjects who never smoked: OR = 1.09 (0.73-1.62; p = 0.676). These results support the hypothesis of gene-environmental interaction in periodontitis.

Dose-effect relation of smoking and the interleukin-1 gene polymorphism in periodontal disease.

BACKGROUND: Periodontitis is a bacterial inflammatory disease leading to attachment loss with the consequence of tooth loss. There exists a multifactorial risk pattern including bacterial challenge, smoking, age, gender, diabetes, and socioeconomic and genetic factors. Smoking has the highest impact on the course of the disease modulated by all the other factors. Here, we report the relationship between smoking and the genetic polymorphism of interleukin-1 (IL-1). METHODS: In a randomly selected population-based study, we genotyped 1,085 test persons for the IL-1 genotype, examined their periodontal status, and assessed their smoking behavior including present and past quality and quantity of smoking. RESULTS: There was a significant dose-effect relationship between the exposure to tobacco smoke and the extent of periodontal disease assessed as attachment loss and tooth loss. Moreover, there was a gene-environmental interaction. Subjects bearing at least one copy of the variant allele 2 at positions IL-1A -889 and IL-1B +3954 (genotype positive) had an enhanced smoking-associated periodontitis risk as compared to their IL-1 genotype-negative counterparts. With genotype-negative non-smokers as a reference, logistic regression resulted in odds ratios of 0.98 (95% confidence interval: 0.83 to 1.14), 2.37 (1.96 to 2.87), and 4.50 (2.30 to 8.82) for genotype-positive non-smokers, genotype-negative smokers, and genotype-positive smokers, respectively. CONCLUSIONS: There is a gene-environmental interaction between smoking and the IL-1 genetic polymorphism. Smokers bearing the genotype-positive IL-1 allele combination have an increased risk of periodontitis. The IL-1 genotype has no influence in non-smokers.

The association between anterior crossbite, deep bite and temporomandibular joint morphology validated by magnetic resonance imaging in an adult non-patient group.

The aim of this study was to determine whether associations exist between anterior edge-to-edge bite, anterior crossbite, deep bite and morphology of the temporomandibular joint (TMJ) in the vertical dimension, evaluated by magnetic resonance imaging (MRI) in adults. A total of 148 subjects (90 females, 58 males) were selected from the cross-sectional epidemiological population-based study "Study of Health in Pomerania" (SHIP) for this evaluation. In each person a clinical orthodontical examination was performed. Four linear measurements and one ratio from MRI scans of the TMJs were evaluated. To estimate the effects of anterior edge-to-edge bite, anterior crossbite and deep bite on TMJ variables, linear regression was applied. (Analyses were adjusted for sex, age, school education, and orthodontic treatment.) Anterior edge-to-edge-bite/crossbite had shorter mean eminence heights (eh) on both joint sides (p<0.01). In deep bite without gingival contact the postglenoid process height (pgph) decreased significantly in left joints (p=0.018) and there was a tendency to a decrease in right joints (p=0.059). The ratio between eminence height and postglenoid process height (eh/pgph) was increased on both left (p<0.001) and right (p=0.002) joints. In conclusion, anterior edge-to-edge-bite/crossbite is connected to a reduced eminence height and deep bite without gingival contact with an increased ratio between eminence height and postglenoid process height. Therefore the condylar path in the anterior edge-to-edge bite and crossbite cases can be interpreted to be reduced and in the deep bite cases without gingival contact to be steepened.

The factors associated with body mass index in adults from the study of health in Pomerania (SHIP-0), Germany.

OBJECTIVE: To investigate the relation between dental status, BMI and systemic diseases and to evaluate the risk factors for having a higher BMI. MATERIALS AND METHODS: Apopulation based cross sectional study of 6248 subjects aged 18-80 years (response of 68.8%, n=4310) was conducted in the Study of Health in Pomerania (SHIP-0). Socio-demographic, medical and oral health information was recorded by 5 dentists at two similarly equipped medical/dental services in the cities of Greifswald and Stralsund. Bivariate statistics, multivariate statistics, linear and logistic regression models were performed to assess the relationship between following covariates: gender, educational level, family status, social activities, income, quality of life (SF-12), smoking, alcohol abuse, diabetes, renal disease, high blood pressure, dental status and high physical activity. RESULTS: Significant risk factors for subjects having a higher BMI were: high blood pressure (OR=2.28), diabetes (OR=2.10), educational level (low: OR=1.49; medium OR=1.27), male (OR=1.32) and former smoker (OR=1.20). whereas young age, being single and being dentate (natural teeth, replaced teeth or fixed teeth) was shown to be protective for having a "high" BMI. CONCLUSION: The most important predictors of BMI were shown to be social and medical factors. Dental factors are most significantly influenced by social factors and also exhibit an important impact on BMI.

The peritoneal explant test for evaluating tissue tolerance to mouthrinses.

The tissue cultures of explants of neonatal rat peritoneum have been demonstrated to be a sensitive test for tissue compatibility with wound antiseptics. The present study investigated the suitability of this method to assess the relative toxicity of mouthrinses to tissue. Mouthrinses containing 0.1% chlorhexidine (Chlorhexamed Fluid 0.1%) (A), 0.3% triclosan (Colgate) (B), essential oil in ethanolic solution (Listerine) (C), and amine/stannous fluoride (Meridol) (D) were tested at use concentration and in dilutions of 10, 1, and 0.1% with exposure times of 1, 10, and 30 min, respectively. The mouthrinses (test) and Ringer's solutions (control) were applied to opened rat peritoneum. After thorough irrigation with Ringer's solution, a piece of peritoneum was removed and 1 x 1 mm explants were cut. The explants were cultivated with a bovine serum culture medium in 24-well plates at 37 degrees C in a CO2 incubator (95% air, 5% CO2). After 10 days, the tissue proliferation for the explants was assessed by a stereo microscope at 10x magnification after ethanol fixing and hemalaun staining. With 24 grafts per test, the proliferation rate was calculated relative to a control, which was run for each mouthrinse and concentration/time combination. Data were analyzed using ANOVA (SPSS 11.0) and post-hoc paired t test. Statistical significance of all correlations was tested by setting the significance level at p < 0.05. At most concentrations, D caused significantly less tissue damage than A or B. There was no difference between C and A or C and B at 100%. However, the toxicity of C was significantly less than A or B at 10, 1, and 0.1%. C and D behaved similarly except for the 10% (30 min) and the 1% (10 min) solutions in which C was significantly less toxic. We concluded that the rat peritoneum explant test was demonstrated to be a sensitive test to assess the relative toxicity of mouthrinses to tissue.

Effectiveness of sealants in adolescents with high and low caries experience.

The aim of this 3-year longitudinal study was to analyze caries increment and the caries-preventive effect of sealants in adolescents in the setting of the German national health system. 434 pupils (193 male, 241 female) took part in compulsory school examinations at age 12 (mean 12.3 +/- 0.4 years) and 15 (mean 15.6 +/- 0.3 years) according to WHO criteria, including the examination of sealants. Mean DMFT increased from 1.78 (+/- 2.15) to 3.97 (+/- 3.68), mean DMFS from 2.79 (+/-4.07) to 6.94 DMFS (+/- 8.34), respectively. Logistic regression analysis showed that high caries incidence at the individual level was mostly associated with the type of school ('Gymnasium', RR = 0.3), gender (female, RR = 2.08) and high baseline DMFS (RR = 1.2 per surface), but not with the number of sealants. In an interaction model, adolescents with high baseline DMFS values had an even higher risk of caries increment with an increasing number of sealants compared to adolescents with fewer sealants (p = 0.047). At the tooth level, this effect was detected for first permanent molars, while sealants in premolars and second permanent molars did not result in a statistically significant caries-preventive effect due to the low caries incidence on these surfaces. Thus, sealants on occlusal surfaces of first permanent molars were only protective in individuals with low or moderate caries activity (p = 0.006), which indicates the need for other measures to reduce caries activity in high risk adolescents. In addition, rates of 19% lost sealants and 18% carious or filled surfaces in 3 years suggest a discrepancy between sealant retention under real-life conditions and the results of controlled clinical trials.

Inverse association between periodontitis and respiratory allergies.

BACKGROUND: Periodontitis is an infection with systemic effects and a high prevalence among adults. In the aetiology of allergic diseases the hygiene hypothesis claims that infections in early infancy may protect against allergic diseases. OBJECTIVE: The aim of the present analyses was to investigate the independent relation between periodontitis and respiratory allergies such as hayfever, house dust mite (HDM) allergy and asthma. METHODS: From the Study of Health in Pomerania (SHIP) a total number of 2837 subjects aged 20 to 59 years were included in the analysis. In our study population 326, 111 and 114 subjects were classified as suffering from hayfever, HDM allergy or asthma, respectively. The attachment loss (AL) were measured. Periodontitis was defined according to the percentage of surfaces which exceeded 3 mm AL [healthy: 0-7.7%, mild: 7.8-28.6%, moderate: 28.7-63.9%, severe: >63.9%]. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using logistic regression. RESULTS: After adjustment for confounding factors these analyses revealed inverse associations between periodontitis and hayfever as well as periodontitis and HDM allergy. For increasing AL, a trend of decreasing risk could be observed for hayfever (healthy: reference; mild AL: OR 0.87 [95%-CI 0.6-1.2]; moderate AL: OR 0.80 [95% CI 0.6-1.2]; server AL: OR 0.53 [95% CI 0.3-0.9]; P(trend)=0.01) and for HDM allergy (healthy: reference; mild AL: OR 0.80 [95% CI 0.5-1.3]; moderate AL: OR 0.64 [95% CI 0.3-1.2]; server AL: OR 0.39 [95% CI 0.2-0.9]; P(trend)=0.02). Furthermore, for asthma were observed a slightly inverse association in the full-adjusted model (healthy: reference; mild AL: OR 1.10 [95% CI 0.6-2.0]; moderate AL: OR 0.96 [95% CI 0.5-1.8]; server AL: OR 0.48 [95% CI 0.2-1.0]; P(trend)=0.11). CONCLUSION: There is an inverse association between periodontitis and respiratory allergies. Our results might support the hygiene hypothesis.

Epidemiological evaluation of the multifactorial aetiology of abfractions.

The purpose of this study was to determine risk indicators for the aetiology of abfractions (cervical wedge-shaped defects) on teeth using dental and medical variables obtained in a population-based sample of the cross-sectional epidemiological 'Study of Health in Pomerania' (SHIP). Medical history, dental, and sociodemographic parameters of 2707 representatively selected subjects 20-59 years of age with more than four natural teeth were checked for associations with the occurrence of abfractions using a two-level logistic regression model on a tooth and a subject level. The estimated prevalence of developing abfractions generally increased with age. The following independent variables were associated with the occurrence of abfractions: buccal recession of the gingiva, odds ratio (OR) = 6.7; occlusal wear facets of scores 1, 2 and 3, OR = 1.5, 1.9, 1.9; tilted teeth, OR = 1.4; inlays, OR = 1.6; toothbrushing behaviour, OR = 1.9 to 2.0 (two and three times a day versus once a day). First premolars had the highest estimated risk for developing abfractions, followed by the second premolars. Maxillary and mandibular teeth behaved similarly in terms of abfractions, with the exception of mandibular canines, which had a much lower estimated risk of incurring abfractions than did maxillary canines. The results of this analysis indicated that abfractions are associated with occlusal factors, like occlusal wear, inlay restorations, altered tooth position and tooth brushing behaviour. This study delivers further evidence for a multifactorial aetiology of abfractions.

Responder and nonresponder analysis for a caries prevention program.

To be able to generalize studies, it is important to know whether responders and nonresponders differ significantly. These data are usually not available. To assess whether responders and nonresponders differed significantly, 319 first and second graders in Greifswald, Germany took part in a compulsory dental school examination. Their parents completed a questionnaire on oral health topics and were asked to decide about their children's participation in a school-based caries prevention program plus anonymous scientific evaluation. The 91 children who were not allowed to participate (nonresponders) were older (mean 8.5 years) than the 228 responders (mean 8.1 years; p < 0.001), mostly because of a few older children having repeated a grade. In an age-adjusted analysis, nonresponders exhibited in 21 of 30 indices of higher caries and plaque values, less preventive measures and a lower rate of participation. The difference in caries in the permanent dentition and fluorosis reached statistical significance. This study suggests that nonresponders to caries prevention programs might comply less with preventive measures and exhibit poorer oral health than responders: a result which has to be taken into account in research and prevention programs in the community.

Risk determinants of periodontal disease--an analysis of the Study of Health in Pomerania (SHIP 0).

BACKGROUND: In this study, risk determinants were determined for periodontal disease in the representative population sample (n=3146) of the Study of Health in Pomerania. METHODS: After examining the net random sample (response 69%) and exclusion of edentulous cases and those with missing values, 2595 subjects remained. Using a multivariate, fully adjusted logistic regression, different definitions of "periodontally diseased/healthy" were examined as the dependent variable (extent of attachment loss (AL> or =4 mm, combined AL and tooth loss). The independent variables used were sociodemographic factors (age, gender, income, education), medical factors (systemic diseases, drugs), behavioral factors (regular dental checkup, smoking), and oral factors (presence of supragingival calculus and plaque). RESULTS: The following risk determinants were found for AL: male gender, presence of supragingival plaque and calculus, smoking, low educational level. For the combination of AL and tooth loss, risk determinants were female gender, supragingival plaque, smoking, and low educational level. Consumption of antiallergic medications and regular dental checkups proved to be protective. Smoking was the most influential risk determinant. These parameters explained approximately 43-55% of the variation. CONCLUSION: These results concur with those of the literature. In order to explain disease status further, host-response and microbiological factors must also be examined.

Surface wear on cervical restorations and adjacent enamel and root cementum caused by simulated long-term maintenance therapy.

BACKGROUND: In an in vitro study, the surface wear on cervical restorations and adjacent enamel and root cementum caused by different tooth-cleaning methods in simulated long-term therapy was investigated. METHODS: Cervical restorations of amalgam (Oralloy), modified composite resin (Dyract), glass-ionomer cement (ChemFill Superior), and composite (Tetric) were instrumented by POL (polishing), CUR+POL (curette and polishing), US+POL (ultrasonic device with polishing) and the polishing agents Cleanic and Proxyt in a computer-controlled test bench. Treatment time corresponding to a real-time period of 5 or 10 years. Substance loss from instrumented surfaces was measured with a digital gauge. A three-way anova was used in the statistical evaluation. RESULTS: The results showed that POL led to slight substance loss, which was greater using Cleanic (27 microm) than Proxyt (5 microm). CUR+POL produced a significantly greater substance loss than did US+POL, with 186 microm versus 35 microm on glass-ionomer cement, respectively, and 123 microm versus 18 microm, respectively, on root cementum, followed by composite (111 microm versus 27 microm, respectively), polyacid modified composite resin/compomer (89 microm versus 36 microm), amalgam (75 microm versus 19 microm), and enamel (32 microm versus 23 microm). CONCLUSIONS: As opposed to the use of US+POL or POL, substance loss on cervical restorations and especially root cementum must be expected to result from tooth-cleaning during long-term maintenance treatment using CUR+POL.

Observations on experimental marginal periodontitis in rats.

OBJECTIVE: The purpose of this study was to assess periodontal destruction following experimentally induced marginal periodontitis in rats by ligatures over a 60-day observation period. The extent to which the physiological movement of teeth influenced the effect of the ligatures was also examined. In addition, two methods for measuring bone loss in the defleshed jaw were compared. METHODS: Thirty-five male Sprague-Dawley rats (SD) were divided into five groups. Marginal periodontitis was induced by ligatures on the second maxillary molars. Rats were killed after 15, 30, and 60 days. Rats in the control group were killed on day 1 and day 60. Bone loss was determined with two different methods on the buccal and palatinal surfaces of the defleshed jaw. In the first method, the distance of the cementoenamel junction (CEJ) from the alveolar bone crest (ABC) was measured at different sites; in the second method, the area of the exposed root surface of the molars was measured. RESULTS: Comparison of the control groups from day 1 and day 60 using both measuring methods showed significant differences in bone loss. In the area where the ligature was located, test rats exhibited significantly greater bone loss than control rats. Comparison of control rats from day 1 with test rats from day 15 showed that the increase in bone loss between the groups within the area of the ligature was significantly greater than outside it. The age-dependent bone loss increases over the entire observation period of 60 days. The ligature-induced bone loss increased most from day 1 to day 15; on days 30 and 60, slighter increases in bone loss were observed. CONCLUSIONS: The application of this model can only be recommended for short (

Learning root debridement with curettes and power-driven instruments. Part II: Clinical results following mechanical, nonsurgical therapy.

BACKGROUND, AIMS: In a manikin study we recently assessed how effectively student operators were able to learn scaling with curettes (GRA) and power-driven instruments (PP). Calculating the debrided root area effectiveness was low in both groups without systematic training or without a motivational program. After 10 weeks (20 h) of training, operators reached a high effectiveness of 84.7% (GRA) and 81.6% (PP). The purpose of the present study was to evaluate the clinical outcome of nonsurgical treatment as performed by these student operators. METHODS: In a clinical trial, 19 students trained in the use of Gracey curettes for 10 weeks (=20 h) (GRA10) and Periopolisher system for 1 week (=2 h) (PP1), and 20 students trained in the use of Gracey curettes for 1 week (GRA1) and the Periopolisher for 10 weeks (PP10) treated one patient each in a split-mouth design. At baseline and 6 months, we recorded probing depth (PD), probing attachment level (PAL) and bleeding on probing (BOP) by computer-assisted probing. Statistical analysis was carried out for moderate (category B) and deep sites (category C). Groups were compared using Student's t-tests (p<0.05). RESULTS: Category B sites showed a PD reduction of 1.2/1.0 mm (GRA10/GRA1) and 1.1 mm (PP10/PP1). PAL gain was 0.5/0.3 mm (GRA10/GRA1) and 0.4/0.2 mm (PP10/PP1). In category C sites, PD reduction was 2.1/2.3 mm (GRA10/GRA1) and 2.0 mm (PP10/PP1) with a PAL gain of 0.6/0.9 mm (GRA10/GRA1) and 0.4 mm (PP10/PP1). BOP was significantly lower in all groups. CONCLUSION: The results show that student operators who had received a systematical training on manikins and had attained different effectiveness results were able to treat periodontally diseased patients successfully using both Gracey and Periopolisher instruments.

Learning root debridement with curettes and power-driven instruments in vitro: the role of operator motivation and self-assessment.

The influence of systematic dummy-head training with Periopolishe (PP, group A) and Gracey instruments (GRA, group B) on the effectiveness of root debridement was evaluated by Rühling et al., 2002 (9). Their results indicate that independent of the instrument used, untrained operators were only able to debride root surfaces at low levels of effectiveness. It was possible to increase effectiveness to a high level through systematic training in both groups. The aim of the present study was to assess the role of operator motivation and self-assessment on scaling effectiveness. Before baseline, operators were asked to answer a questionnaire rating the expectation of the instrument performance. Four groups of inexperienced operators (n = 11 each) received 10 weeks dummy-head training. In groups A (GRA) and B (PP), training was combined with a motivational programme. Groups C (GRA) and D (PP) received the same training, but no additional motivational programme. In a dummy-head, 10 test teeth were debrided and operators were asked to estimate their effectiveness of debridement at each test day. Effectiveness was calculated as percentage of debrided root area on 10 test teeth at different time points with an image analysis programme (NIH Image) and ANOVA. Two groups were compared using the Mann-Whitney U-test (unpaired) and the Wilcoxon signed ranks test (paired). Motivated groups (A and B) reached about 25% higher debridement results (p < 0.001) and were able to estimate their effectiveness more precisely compared to groups C and D. In the low motivation groups (C and D), overestimation of more than 20% was evident (p < 0.001). The questionnaires revealed underestimation of the GRA instruments and overestimation of PP instruments. Operator motivation and self-assessment greatly influence learning of effective root debridement.

Learning root debridement with curettes and power-driven instruments. Part I: a training program to increase effectivity.

BACKGROUND/AIMS: In a dummy-head trial, we assessed how effectively untrained operators were able to learn scaling with curettes and power-driven instruments. METHODS: Two untrained operator groups (n = 11 each) received six 2-h lessons during a 10-week period following a training program. Subgingival scaling was performed with curettes (GRA) and a power-driven system (PP). At 6 test days each subject had to instrument 10 test teeth. The percentage of debrided area was assessed with an image analysis program. Learning success was measured as a percentage of debrided root area and scaling time. Furthermore, the effectivity was related to difficulty in anatomical situations and access to root surfaces. Statistical analysis was carried out with SPSS. RESULTS: At baseline, effectivity was 63.1% (GRA) vs. 52.3% (PP). Between weeks 9 and 11, operators reached a plateau for group GRA at 84.7% and group PP at 81.3%. Scaling time did not differ between the two groups. Debridement of teeth with complex root shapes that were hard to access was less effective with the power-driven system. CONCLUSION: Independent of the instrument used, untrained operators were only able to debride root surfaces at low levels of efficacy. With systematical training, effective scaling with the power- driven system was as easy to learn as with hand instruments. On root surfaces with complicated shape and anatomy or difficult accessibility, the power-driven system works significantly less effectively.