Computerized evaluation of the effectiveness of subgingival scaling in jaw models. An introduction to the program developed at the School of Dentistry, University of Bergen

Impact of scientific and technological advances

Advancements in research and technology are transforming our world. The dental profession is changing too, in the light of scientific discoveries that are advancing biological technology-from new biomaterials to unravelling the genetic make-up of the human being. As health professionals, we embrace a model of continuous quality improvement and lifelong learning. Our pedagogical approach to incorporating the plethora of scientific-technological advancements calls for us to shift our paradigm from emphasis on skill acquisition to knowledge application. The 2017 ADEE/ADEA workshop provided a forum to explore and discuss strategies to ensure faculty, students and, ultimately, patients are best positioned to exploit the opportunities that arise from integrating new technological advances and research outcomes. Participants discussed methods of incorporating the impact of new technologies and research findings into the education of our dental students. This report serves as a signpost of the way forward and how to promote incorporation of research and technology advances and lifelong learning into the dental education curriculum.

Clinical response to experimental forces and non-surgical therapy of teeth with various alveolar bone loss

Firm lateral force is necessary for the thorough removal of calculus during scaling and root planning (SRP) with hand instruments. However, this firm lateral force should be applied to root surfaces without considering the tooth's loss of supporting tissues. The purpose of the present study was two-fold: firstly, to evaluate the initial pain response of periodontally diseased non-molar teeth with two different levels of alveolar bone loss (ABL) to experimental lateral and vertical pull forces; and secondly, to examine the clinical response of these teeth to non-surgical therapy. Twenty patients with chronic periodontitis were specifically selected in two groups according to the level of ABL at non-molar teeth. Group I consisted of 10 patients who have 141 non-molar teeth with a radiographic evidence of 40-65% ABL. Group II consisted of 10 patients who have 132 non-molar teeth with a radiographic evidence of > or =70% ABL. All patients were systemically healthy, free of pain, and reported no current medication usage. Starting from 0 and gradually increasing an experimental lateral force with digital force gauge, and also an experimental vertical pull force with mechanical force gauge were applied to each tooth and measured. As a result of a single experimental force applied to each non-molar tooth, the initial pain response emerged in the patients was determined by means of electronic bell system used by patients themselves. Each patient was treated with SRP using specific hand instruments under local anesthesia. Plaque index (PI), gingival index (GI), probing depth (PD), clinical attachment level (CAL) and periotest values (PV scores) were compared in both groups at initial and at month 3. A mean experimental lateral force of 24.6 N and a mean experimental vertical pull force of 48.3 N caused initial pain response in group I. Initial pain response occurred with a mean experimental lateral force of 5.3 N and a mean experimental vertical pull force of 19.4 N in group II. Only group I showed statistically significant decrease in PI, GI, PD and a significant attachment gain at month 3 (P < 0.05). There was a decrease of 6 PV in group I at month 3 (P < 0.05), whereas an increase of 4 PV was observed in group II (P > 0.05). This study showed that lateral and vertical forces required for effective SRP do not cause any problem in the group with 40-65% ABL. However, they may cause trauma in the group with approximately 70% ABL. Thus, the results suggest that the degree of healing would be different in the group with > or =70% ABL and in the group with 40-65% ABL.

Gingival enlargement in acromegaly

In this study, we investigated gingival enlargement in patients with acromegaly as a component of the disease. Eleven patients (5 males, 6 females) were evaluated. Diagnosis was confirmed with typical clinical features and laboratory. Oral examinations were carried out by the same periodontist. During the examination, plaque index, gingival index, probing pocket depths, and gingival enlargement values were evaluated. Duration of the disease was between 0.2 and 13 yr. Seven patients had pituitary macroadenomas and four had microadenomas during their initial diagnosis. Only one patient was newly diagnosed. The other patients had previously undergone surgery. Gingival enlargement was found in eight patients. Seven patients with gingival enlargement also had prognathism, and one patient had prognathism associated with gingival enlargement. These findings demonstrate that acromegaly that results in overgrowth in various organs should be considered one of the causes of gingival enlargement.

The influence of smoking and non-insulin-dependent diabetes mellitus on periodontal disease

The periodontal health of smokers and non-smokers with non-insulin-dependent diabetes mellitus (NIDDM) and non-smokers with periodontitis who were not suffering from a systemic disease was assessed. The investigation was carried out on 60 adult subjects. Levels of blood glucose, glycosylated haemoglobin and immunoglobulins G, A and M were determined, together with the plaque index, gingival index, probing pocket depths and clinical attachment level. Periodontitis was more severe in smokers and non-smokers with NIDDM than non-smokers without NIDDM, and the periodontal condition (clinical attachment level, probing pocket depth and gingival bleeding) was better in non-smokers with NIDDM than smokers with NIDDM. The results suggest that diabetes and smoking are high-risk factors for periodontal disease.

Effectiveness of subgingival instrumentation with power-driven instruments in the hands of experienced and inexperienced operators. A study on manikins

Power instrumentation of periodontally-diseased root surfaces is gaining in significance as an alternative to conventional curette methods. In an experimental study employing manikins with simulated bone loss, we investigated whether inexperienced and experienced operators were able to achieve greater therapeutic success with power-driven devices than with hand instruments in subgingival scaling. 10 dentists experienced in periodontal treatment and 10 inexperienced dentists instrumented 7 teeth in the upper jaw, which had been covered with artificial deposits. Hand instruments, the Perioplaner system, a sonic and an ultrasonic scaler were used. The time required for treatment was measured and the % of residual deposits was calculated by means of image-processing techniques. Weight loss was also determined for the teeth that were scaled with the hand instruments and the Perioplaner system. Experienced operators left significantly less % of residual deposits on the teeth (18+/-7.6%) than the inexperienced (27+/-8.4%), regardless of the type of instrument selected. Both experienced and inexperienced operators left the smallest amounts of residual deposits with hand instruments (13+/-9.8%/24+/-9.5%). Both treatment groups removed more hard tooth structure with hand instruments than with the Perioplaner system (53+/-48mg versus 47+/-25.9 mg). Experienced operators needed somewhat more time for debridement than unexperienced. Use of the sonic/ultrasonic device required somewhat less time than hand instrumentation. Inexperienced operators are, however, unable to improve their treatment results by using the power-driven instruments included in the study.

Efficacy of 5 machining instruments in scaling of molar furcations

The scaling efficacy of machining instruments was studied in the furcations of 100 extracted molars. The molars were divided into 5 groups with similar furcation anatomy, painted with artificial calculus, partly submerged in stone blocks, and the furcation entrances covered with a heavy rubber dam material. Ten mandibular and 10 maxillary molars were scaled by an experienced operator with each of the following instruments/inserts: ultrasonic instrument with either a prototype ball point insert or with a new pointed insert; ultrasonic instrument with a ball point insert; reciprocating hand-piece with new inserts for furcations; and a sonic scaler with a universal insert. The molar groups were coded and graded in a stereomicroscope by 2 independent examiners, and the rankings were tested with the Kruskal-Wallis test and the multiple comparisons between treatments test. The results revealed statistically significant differences between the instruments, as well as between different topographical areas of the furcations. The sonic scaler with a universal insert and the ultrasonic instrument with ball point inserts were significantly more efficient (P < 0.05) than the reciprocating handpiece with inserts in most of the areas studied. For mandibular molars, significantly better results (P < 0.05) were obtained for lingual furcation entrances than for furcation roofs. For maxillary molars, significantly better results (P < 0.05) were obtained for distal and buccal entrance areas than for furcation roofs and inside of mesial roots. The present study may give some guidance to the practitioner in choosing machining instruments for furcation cleaning as well as identifying the most difficult topographical areas to instrument.

Evaluation of a new periodontal curet. An in vitro study

Removal of plaque and calculus from subgingival root surfaces is a fundamental aspect of periodontal therapy. A new type of periodontal curet (Gracey Curvette Sub-0) has been designed to better adapt to the root surfaces that may be encountered in periodontal pockets of incisor teeth. The new curet (test) was compared to a Gracey curet 1/2 (conventional) in their ability to remove deposits from the subgingival root surfaces of incisor teeth in an in vitro model. A dentiform model mounted on a dental chair was used with artificial gingiva, 6 mm pocket depths and subgingival root surfaces covered with black enamel paint. 2 groups of 12 hygienists used, on a timed basis, either the test or conventional curet on 4 of the incisor teeth and then switched to the alternate instrument for the remaining four incisors. The extent of surface material removal was determined using a computerized video routine. The test curet removed significantly (p less than 0.001) more of the surface material from all subgingival incisor root surfaces than the conventional curet (60.7% versus 46.3%). Both instruments were most effective at labial surfaces. The test curet was least effective at proximal surfaces and the conventional curet least effective at lingual surfaces. The greatest statistical difference between instruments was apparent at lingual surfaces of maxillary incisors and the least at mesial surfaces of mandibular incisors.