Interceptive use of pendulum for advance resolution of class II patient: a guided eruption plan to reduce stress on permanent teeth root.

Use of the so-called distalizing mechanics is a common treatment to correct class II malocclusion. One of the first appliances made for molar distalization was the pendulum, which resulted immediately efficient. The knowledge of pendulum efficacy, in regards to distalizing treatment in adolescence, has guided the research to analyze pendulum effect in childhood: checking the pre-eruptive, natural and distal movement of upper second premolar following first upper molar distalization in order to obtain an advance resolution on Angle's Class II patient, limited treatment time, reduced periodontal inflammation and stress on permanent teeth root. A pilot study testing the possibility of a prospective study was necessary on 6 patients treated following an accurate protocol (6 months and 1-year Rx control) and 6 patient control after one year. Statistical analysis by T-Test was done. Oral hygiene controls every month were done. Second upper bicuspid vertical (1.6mm) and sagittal (2.5mm) movement mean values allow to emphasize a distal variation of tooth axis inclination of treatment group than control group, and a second upper bicuspid distal departure from "gubernaculus dentis" of second deciduous molar in treated patients. Periodontal inflammation appears inexistent on second and first upper premolar germs after the comparison between RX exam of treatment and control groups because of exploiting deciduous teeth. Besides periodontal inflammation and teeth root stress on first upper molar of treatment group, after RX analysis, results were limited compared to control groups because of the advanced orthodontic interceptive treatment during a previous stage of first upper molar root development.

Laser lingual frenectomy: basal eutonia achievement by natural homeostatis.

The aim of present study is a macro evaluation of adjustment to allow homeostasis before and after frenectomy. Macro analysis was done on 7 pediatric patients tested firstly simple surface elettromyography (EMG) to evaluate masticatory muscles, secondly the Romberg's test to assess the posture and thirdly cephalometric analysis according to Giannì and Rocabado to assess orthodontic variations. The frenectomy was performed with diode laser (wavelength 890 nm). Pre-frenectomy EMG outcomes indicate a clear masticatory muscular imbalance with a different electrical activity compared to physiological standard values and functional basal balance. Results after frenectomy EMG show a normalization of basal values with an improvement of mandibular posture. Depending on cephalometric analysis, outcomes reveal a tendency to normalize the cervical lordosis, previously altered. Ultimately, pre-frenectomy Romberg's test shows initial instability in the static posture, which decreases after frenectomy. In conclusion, the short lingual fraenum not only has static correlations with the oral cavity but also dynamic connections with the cervical posture and muscular basal organization. So, homeostasis includes macro alterations involving muscular tone and bone position. Frenectomy could favor the restoration of the basal eutonia achieved by a natural homeostasis.

Frequency of awake bruxism behaviours in the natural environment. A 7-day, multiple-point observation of real-time report in healthy young adults.

The aim of this study was to assess awake bruxism (AB) behaviours in a sample of healthy young adults using a smartphone-based application for a real-time report (ie, ecological momentary assessment [EMA], also called experience sampling method [ESM]). Forty-six dental students used a smartphone application that sent 15 alerts at random intervals during the day for 1 week to collect AB self-reports. They had to answer on time by tapping on the display icon that refers to their current condition of jaw muscles: relaxed; teeth contact; teeth clenching; teeth grinding; jaw clenching without teeth contact (ie, bracing). The average frequency of relaxed jaw muscles, as a percentage of answers over the 7 days, was 71.7%. Teeth contact (14.5%) and jaw clenching (10.0%) were the most frequent AB behaviours. No significant gender differences were detected. Interindividual differences were quite relevant, but the overall frequency was in general only moderately variable from day-to-day. Coefficient of variation (CV) was low for the condition "relaxed jaw muscles" (0.44). At the individual level, teeth contact was the most prevalent behaviour, with a 39.1%-52.2% proportion of subjects reporting it at least once a day. During a 7-day observation period, the frequency of real-time report of AB behaviours in a sample of healthy young adults was 28.3%. The low daily variability in the average frequency value for the relaxed jaw muscles condition suggests that EMA may be a reliable strategy to get deeper into the epidemiology of oral behaviours. This investigation introduced EMA principles to the study of AB and provided data on the frequency of AB behaviours in young adults that could be compared to populations with risk/associated factors and possible clinical consequences.

Evaluation of three different manual techniques of sharpening curettes through a scanning electron microscope: a randomized controlled experimental study.

OBJECTIVE: The purpose of this study was to compare the effectiveness of three different techniques for manually sharpening of periodontal curettes (PCs) by examining the blades with the aid of scanning electron microscope (SEM). METHODS: Three groups were considered based on three sharpening methods used: group A (moving a PC over a stationary stone); group B (moving a stone over a stationary PC) and group C (moving a PC over a stone fixed, placed on a 'sharpening horse'). After the sharpening, the blades were examined using SEM. The SEM images were assessed independently by five different independent observers. An evaluation board was used to assign a value to each image. A preliminary pilot study was conducted to establish the number of samples. Pearson's correlation test was used to assess the correlations between measurements. anova test with Bonferroni's post hoc test was used to compare the three groups. RESULTS: Sixty PCs (20 PCs per group) were used in this study. Statistically significant differences emerged between the three groups (P-value = 0.001). Bonferroni's test showed that the difference between groups A and B was not statistically significant (P-value = 0.80), while it was significant for the comparisons between groups A and C (P-value = 0.005) and between groups B and C (P-value = 0.001). CONCLUSIONS: The sharpening technique used in group C, which involved the use of the sharpening horse, proved the most effective.

Different effects of whitening treatment on natural teeth and teeth treated with Icon resin: an experimental study in vitro.

BACKGROUND: It is quite common for white spots to develop on a tooth, due sometimes to a defective formation of the enamel layer, and sometimes to patches of demineralisation as a result of poor oral hygiene during orthodontic treatment with fixed braces. ICON DMG is currently the only noninvasive treatment for white spots. After a preliminary etching, it infiltrates the enamel, filling the spaces between the prisms with a resinous material that has a refraction coefficient very similar to that of healthy tooth enamel. The aim of this study was to test the efficacy of professional whitening procedures on teeth previously treated with ICON. The study hypothesis was that infiltration with ICON resin creates a barrier capable of preventing the bleaching action of the whitening agent. MATERIALS: White spots were artificially created on one half of the vestibular surface of 12 human teeth, while the other half was protected with a composite adhesive. The white spots were infiltrated with ICON and the protective adhesive was subsequently removed. A professional teeth whitening procedure was then completed on both halves of the teeth. A statistical analysis was performed to compare spectrophotometric recordings obtained before and after the ICON infiltration and teeth whitening procedures. CONCLUSION: The whitening procedure modified the colour of the teeth on the half not infiltrated with ICON (p<0.05), but there was no statistically significant change in colour on the half infiltrated with ICON. The presence of the ICON resin seems to act as a partial barrier to the action of the whitening agent.

Scissor bite in a young patient treated with an orthodontic-orthopedic device. A case report.

BACKGROUND: Scissor bite is a rare malocclusion that often leads to minor facial asymmetry. An orthodontic and orthopaedic correction is advisable in young patients to prevent subsequent temporomandibular diseases requesting maxillofacial intervention. CASE REPORT: In this case report a 8-year-old girl in mixed dentition with unilateral left scissor bite was treated with a modified Rapid Palatal Expander. To modify an overexpanded maxilla (width 39 mm measured between both upper first molars) the device was used to close rather than to expand, without need of patient compliance. Orthodontic correction was then completed with traditional bracketing. Results were tangible (width 36 mm) and remained stable even for at least 2 years after retention. This original device has proved to be useful in this kind of situations and can be easily applied to young patient to correct such malocclusions.

Respiratory disorders in paediatric age: orthodontic diagnosis and treatment in dysmetabolic obese children and allergic slim children.

AIM: Obesity and allergic susceptibility are worsening problems in the most industrialised countries. With different mechanisms, they both lead to a deterioration of children's life quality because they affect the respiratory system, leading to asthma and respiratory disorders such as mouth breathing and obstructive sleep apnoea. The latter are related to specific types of malocclusions that require an early diagnosis and specific multidisciplinary treatment. The purpose of this work is to show the characteristic signs and symptoms of these disorders in children of the two phenotypes (allergic and slim, obese and dysmetabolic). Intercepting such issues allows both pediatricians and paediatric dentists to refer the child to a multidisciplinary team of specialists able to deal, in a holistic way, with both the physical and behavioural causes, and also with the consequences on systemic and craniofacial development in particular. MATERIALS AND METHODS: The literature available on this topic in the years between 1997 and 2011 was reviewed, paying special attention to prevention, paediatric visits, diagnostic tools and treatment options for each of the two conditions. CONCLUSION: Dysmetabolic obese children and allergic slim children have specific respiratory problems during rest and exercise. Mouth breathing and obstructive sleep apnoea are due to an abnormal craniofacial development and can cause serious systemic problems in adulthood. Intercepting early signs of pathognomonic symptoms of sleep aponea and mouth breathing permits to treat children with an early multidisciplinary approach, and allows for proper physical and psychological development of the child.

Conscious sedation with diazepam and midazolam for dental patient: priority to diazepam.

AIM: The aim of this paper was to determine whether the use of midazolam is a better technique than the use of diazepam, in relation with the definition of conscious sedation in dentistry. METHODS: Eighty-eight patients undergoing oral surgery were divided into 2 groups in which the sedation was randomly achieved with equipotent cumulative doses of diazepam and midazolam, up to a maximum dose of 8 and 4 mg respectively. Patient's tranquillity was assessed after every dose, using a visual analogue score to ten points and the sedation was evaluated as mild, moderate or deep. Blood pressure, heart rate and SpO2 were also recorded. Psychomotor conditions, by Newman test, and the incidence of amnesia and the patient's satisfaction, by telephone interview, were both evaluated. RESULTS: The number of patients who reached maximum subjective tranquillity was greater already after the third dose of diazepam. The average scores of tranquillity were higher after diazepam. Patients treated with diazepam experienced a higher incidence of mild sedation, patients treated with midazolam a higher incidence of moderate and deep sedation. In patients treated with midazolam blood pressure, heart rate and SpO2 were lower. Postoperative recovery was similar in the 2 groups. After midazolam patients experienced greater amnesia for local anesthesia and drowsiness. Satisfaction was high with both treatments. CONCLUSION: The study shows that sedation with diazepam is more in line with the definition of conscious sedation in dentistry. Diazepam guarantees the persistence of consciousness and maximum subjective tranquillity levels. The recovery and satisfaction were comparable in the 2 groups.

Non-compliant maxillary protraction by orthodontic micro-implants.

AIM: Delaire-type facemask is still the appliance of choice for non surgical paediatric Class III treatment. However, it entails great aesthetical problems and is totally dependent on patient compliance. A new modified maxillary protractor was then designed: it is monomaxillary, fixed, implant-supported, aesthetically pleasing and it does not require patient compliance. The aims of this study were to evaluate the clinical use and analyse the effects of a new appliance called Fixed Maxillary Protractor. The device aims at obtaining a forward movement of the maxillary dento-alveolar component in non-compliant paediatric patients, when mandible retrusion cannot be pursued. CASE REPORT: A non-compliant patient aged 4 years 11 months with mild skeletal and predominant dento-alveolar Class III malocclusion with maxillary deficiency, anterior crossbite and complete deciduous dentition was treated for 10 months. The appliance, anchored by 2 micro-implants in the posterior palatal region, consisted of an acrylic plate, a lingual splint, 2 TMA springs that delivered a posterior-anterior force, 2 anterior security devices and 2 occlusal bite raising splints on the deciduous molars. The treatment yielded a slightly overcorrected Class I incisal relationship. Increase in SNA angle (2°) and a decrease in SNB angle (1°) resulted in an increase in ANB angle (3°). Increases in Wits appraisal of 4 mm and in overjet of 7 mm were obtained. A correction of the anterior crossbite the a posterior sliding of the mandible due to the crossbite correction were observed. An anticlockwise rotation of the maxilla and a mild increase in the anterior facial height were achieved: the treatment effects are similar to those obtained with the Delaire-type facemask, but the amount of postero-anterior correction is lower. DISCUSSION AND CONCLUSION: The Fixed Maxillary Protractor is effective for the treatment of mild-moderate Class III malocclusion with maxillary deficiency in non-compliant paediatric patients.

Orthopaedic treatment efficiency in skeletal Class III malocclusions in young patients: RME-face mask versus TSME.

AIM: To cephalometrically compare the skeletal vertical and sagittal effects of TSME with those of RME protraction facemask therapy in Class III patients. MATERIALS AND METHODS: The sample of this retrospective study included 104 patients (53 females, 51 males) with age ranging from 5 to 9 years, presenting a skeletal Class III relationship: 52 were treated with transverse sagittal maxillary expander (TSME) appliance (Group 1) and 52 with Hyrax rapid maxillary expander/facemask (RME/FM, Group 2). For each patient a lateral cephalogram was obtained before treatment (T0) and at the end of the retention period (T1). Changes in the two groups during the observation period were calculated, compared and statistically analysed with t-test. RESULTS: TSME can produce skeletal changes and dento-alveolar modifications. RME in association with protraction facemask showed that after treatment the maxilla was moved significantly forward. The correction of the ANB angle was due to a change in mandibular position during treatment which showed a backward and downward rotation. CONCLUSION: Both devices were effective in the treatment of subjects with skeletal Class III due to maxillary retrusion.

A new methodological and clinical approach for the treatment of upper lateral incisors agenesis: the posterior space opening.

UNLABELLED: AIM The purpose of this study is to present a new clinical approach for the treatment of upper lateral incisor agenesis. MATERIALS AND METHODS: A new treatment option was conceived and applied: posterior space opening as a safeguard of occlusal integrity and dental and periodontal aesthetics of the front teeth. This is acheved by means of the anterior space closure, with the mesialisation of the canines and the bicuspids, combined with a posterior space opening to create adequate room for the placement of an implant in the second premolar area. The obtained space should be maintained with a space retainer or a provisional Maryland bridge until the patient is old enough to undergo implant rehabilitation and the canines must be reshaped into a lateral incisor. CONCLUSION: The results of this treatment are a correct teeth alignment, without diastema, Class I occlusion, and occlusal integrity with all natural teeth in the anterior area. In this way there are many advantages for the patient; so it is an effective approach.

Surface electromyography of jaw muscles and kinesiographic recordings: diagnostic accuracy for myofascial pain.

The present investigations attempted to assess the diagnostic accuracy of commercially available surface electromyography (sEMG) and kinesiography (KG) devices for myofascial pain of jaw muscles. Thirty-six (n = 36) consecutive patients with a research diagnostic criteria for temporomandibular disorders (RDC/TMD) axis I diagnosis of myofascial pain and an age- and sex-matched group of 36 TMD-free asymptomatic subjects underwent sEMG and KG assessments to compare EMG parameters of the masseter and temporalis muscles as well as the jaw range of motion and the interarch freeway space. EMG data at rest were not significantly different between myofascial pain patients and asymptomatic subjects, while the latter achieved significantly higher levels of EMG activity during clenching tasks. Symmetry of muscle activity at rest and during clenching tasks, KG parameters of jaw range of motion and the measurement of the interarch vertical freeway did not differ between groups. Receiver operating characteristics curve analysis showed that, except EMG parameters during clenching tasks, all the other outcome sEMG and KG measures did not reach acceptable levels of sensitivity and specificity, with a 30·6-88·9% percentage of false-positive results. Therefore, clinicians should not use sEMG and KG devices as diagnostic tools for individual patients who might have myofascial pain in the jaw muscles. Whether intended as a stand-alone measurement or as an adjunct to making clinical decisions, such instruments do not meet the standard of reliability and validity required for such usage.

Toward the validation of visual analogue scale for anxiety.

Anxiety is a relevant problem in dental practice. The Visual Analogue Scale for Anxiety (VAS-A), introduced in dentistry in 1988, has not yet been validated in large series. The aim of this study is to check VAS-A effectiveness in more than 1000 patients submitted to implantology. The VAS-A and the Dental Anxiety Scale (DAS) were administered preoperatively to 1114 patients (459 males and 655 females, age 54.7 ± 13.1 years). Statistical analysis was conducted with Pearson correlation coefficient, the receiver operating characteristic (ROC) curve, and McNemar tests. A close correlation between DAS and VAS-A was found (r  =  0.57, P < .0001); the VAS-A thresholds of dental anxiety and phobia were 5.1 and 7.0 cm, respectively. Despite a significant concordance of tests in 800 cases (72%), disagreement was found in the remaining 314 cases (28%), and low DAS was associated with high VAS-A (230 cases) or vice versa (84 cases). Our study confirms that VAS-A is a simple, sensitive, fast, and reliable tool in dental anxiety assessment. The rate of disagreement between VAS-A and DAS is probably due to different test sensitivities to different components of dental anxiety. VAS-A can be used effectively in the assessment of dental patients, using the values of 5.1 cm and 7.0 cm as cutoff values for anxiety and phobia, respectively.

Comparison by means of bispectral index score, between anxiolysis induced by diazepam and sedation induced by midazolam.

AIM: Bispectral Index Score (BIS) is an objective tool to assess sedation depth. Benzodiazepines have different pharmacological profiles and diazepam may be safer than midazolam in this setting. The aim of this study was to compare BIS values observed during anxiolysis after diazepam versus sedation after midazolam. METHODS: Thirty-six patients were randomly assigned to 3 groups: group 1 was treated with i.v. diazepam, groups 2 and 3 with iv midazolam 1 and 3 mg, respectively. Sedation was monitored clinically and by means of BIS. BIS values were evaluated as area under the curve (AUC) and compared by variance analysis. The statistical comparison of other data was performed by variance analysis or, alternatively, the χ2 according to Yates. The statistical significance was indicated by P values <0.05. RESULTS: AUC values were significantly lower after midazolam when compared to AUC values registered in diazepam treated patients; 22.6% of the group 3 patients showed BIS values <80, versus 0.4% of group 1 patients. CONCLUSION: Diazepam has a safer profile, with BIS values and clinical conditions according to the definition of minimal and/or moderate sedation. Diazepam represents the safer drug for anxiety management in dentistry, because regularly produces a state of sedation during which verbal contact with the patient is maintained and carry a margin of safety wide enough to render loss of consciousness unlikely.

Tooth fragment reattachment through the use of a nanofilled composite resin.

AIM: The purpose of this study is to evaluate resistance to fracture with static tests of dental fragments reattached through the use of different light-curing composite resins. For this purpose 40 bovine inferior incisors were utilised, which were randomised into 4 groups; one control group and 3 experimental groups. MATERIALS AND METHODS: All teeth of the 3 experimental groups were sawed at 3 mm from the incisal margin, and the respective fragments were then reattached utilizing different composite resins: in group 2_EI the hybrid composite Tetric EvoCeram (Ivoclar Vivadent AG) was used, in group 3_ZI the hybrid composite FiltekTM Z250 (3M ESPE) was used, and in group 4_SN the nanofilled composite FiltekTM Supreme (3M ESPE) was used. After reattachment, on each tooth were performed a chamfer on the buccal surface and an overcontour on the lingual surface along the fracture line, which were then filled with the composite resin corresponding to the respective group. Finally, all teeth were embedded in plaster blocks, and a force was applied on the buccal surface. RESULTS: All teeth in groups 2, 3, and 4 showed a significant loss of resistance to fracture compared to the teeth of the control group (P<0.0001). Resistance to fracture of the teeth belonging to groups 2_EI and 3_ZI was 37.35% and 47.35% of that of intact teeth respectively; in group 4_SN resistance to fracture reached 60.05%. Teeth of group 2 exhibited values of resistance to fracture statistically significant from those of group 4 (P=0.024), but no difference was found between group 2 and group 3 (P=0.298). The difference in resistance between group 3 and group 4 was not statistically significant (P=0.199). CONCLUSION: Static test showed that reattachment of coronal fragments do not restore resistance to fracture to the value of intact teeth. Resistance to fracture in in vitro studies is influenced by the type of composite resin utilised.

Patients appreciation for information on anesthesia and anxiolysis in dentistry.

AIM: The research regards information on anesthesia to patients undergoing oral surgery. Every patient evaluated the information received at the end of the preoperative visit and in the postoperative period. METHODS: One hundred-fifty dental patients were asked about the most appreciated information received in the preoperative visit on the anxiolytic technique, local anesthesia and treatment of the perioperative pain. Afterwards the patients had to report on their reaction to the content of the preoperative visit and information quality. On a phone interview they had to evaluate their appreciation of the anxiolytic technique, their perception during loco-regional anesthesia and incidence of pain and edema. RESULTS: The most appreciated details were those on the intervention, pharmacologic treatment, postoperative complicances, postoperative pain and operative competence; less appreciated were those on loco-regional anesthesia, duration of the intervention, anxiolytic techniques, hospital reception and permanence in the hospital. Ninety-eight percent of the patients considered to have been adequately informed on a context judged to be extraordinary (99.3%), 96.6% indicated the information as necessary, 98.6% appreciated the treatment of the intraoperative and postoperative (99.3%) pain and 99.3% the anxiolytic treatment. On the telephone interview, 100% of patients expressed satisfaction for the experienced intraoperative tranquillity, 91.3% complained for not having received in the past a similar preoperative visit, 99.3% wished a diffused application of the information. The loco-regional anesthesia was associated to psychological detachment in 84% of the cases and the incidence of postoperative pain was of 36%. CONCLUSION: The information on the anxiolytic techniques, loco-regional anesthesia, treatment of perioperative pain and postoperative distress was enthusiastically accepted and albeit initially induced feelings of astonishment resulted to be appreciated and preferred in the whole of the patients.

Communication through telemedicine: home teleassistance in orthodontics.

AIM: The aim of the study is codify both a methodological and communication standard based on teleassistance, and the emergencies that can be treated from a remote location along with the related clinical applications, limitations, medicolegal considerations and the patients' opinion on this new opportunity of assistance. MATERIALS AND METHODS: To codify a distance communication method, ten young patients aged 10-16 years, equipped with a mobile videophone and after clear instructions, asked the advice of the orthodontic specialist to deal with minor orthodontic emergencies. Upon completion of the treatment they filled out a questionnaire on satisfaction level and difficulties encountered with the use of this technology. RESULTS AND DISCUSSION: Most of the orthodontic emergencies can be solved at home: rubber ligature displacement, discomfort due to the appliance, irritation of cheeks. Those patients who used the videophone to handle the orthodontic emergencies considered it an easy and useful method, possibly due to the young age of the subjects involved, who are familiar with the new technologies. CONCLUSIONS: Telecommunications applied to medicine and dentistry is currently a subject of topical interest. The most developed countries are investing resources in order to improve assistance and communication between physicians and patients and among specialists. The possibility of sharing videos and images is particularly useful in the orthodontic field, as minor emergencies can be solved easily at home, reassuring patient and parents on one hand, and limiting visits to the dental office to cases of real need.

Nasal function before and after rapid maxillary expansion in children: A randomized, prospective, controlled study.

OBJECTIVES: Children can well detect and respond to odours in order to have information about food and environment. Rapid Maxillary Expansion seems to improve dental and skeletal crossbite and increase nasal patency correcting oral respiration in children. A previous pilot study suggested that Rapid Maxillary Expansion may lead to improved N-Butanol olfactory thresholds, and peak nasal inspiratory flow values (PNIF). The aim of the present study was to prospectively evaluate olfactory threshold, nasal flows and nasal resistances in children aged from 6 to 11 years before and after Rapid Maxillary Expansion, comparing treated children with a control group of similar age, growth stage (prepubertal) and transversal skeletal deficiency. METHODS: N-butanol olfactory thresholds, anterior active rhinomanometry (AAR) and PNIF were measured in 11 children (6-11 years) before (T0), immediately and 6 months after Rapid Maxillary Expansion application (T1 and T2 respectively), and in a control group of 11 children (6-11 years) whose members remained under observation for the period of the study. RESULTS: Considering the study group, PNIF values improved at T1 respect to the T0 values (p = 0.003), while T2 values were significantly higher than T0 ones (p = 0.0002). N-Butanol Olfactory Threshold significantly improved at each control (p = 0.01, p = 0,01 and p = 0.0003, for T1 vs T0, T2 vs T1, T2 vs T0 respectively). No differences on AAR values were found during the six months follow-up in this group. Considering the control group, no significant differences were found for any of the considered variables during the time of the study. Comparing the two groups, there was a significant increase of PNIF values in the study group compared to the control group (p = 0.003) at T1, which was even more evident six months after Rapid Maxillary Expansion (p = 0.0005). This improvement was not shown by AAR values. N-Butanol Olfactory Threshold showed a significant improvement at T2 respect to T1 (p = 0.002) and T0 (p = 0.0005). CONCLUSION: Rapid Maxillary Expansion seems to significantly improve the respiratory capacity of treated patients, at least in terms of PNIF, and their olfactory function, measured by N-Butanol Olfactory Threshold Test. Further studies should be performed to evaluate if also changes in nasal resistances, measured by AAR, could occur, maybe considering a larger group of subjects and possibly using 4-phase rhinomanometry in order to evaluate the effective resistances during the entire breath.

Comparative evaluation of different techniques of surface preparation for occlusal sealing.

AIM: Aim of this experiment is the efficacy evaluation of three different types of surface preparation techniques by microleakage assessment of two different sealing materials. MATERIALS AND METHODS: Sixty teeth were used for the experiment: half were treated with Admira seal (Voco) and the remaining half with Delton FS+ (Dentsply). Each group was then divided into three subgroups, which underwent three different preparation techniques before sealant placement: mechanical brushing, air abrasion and Intensive bur FG 40D4, respectively. After immersion of the specimens in methylene blue solution, the degree of microleakage was assessed by mean of optic microscope. RESULTS: Results show no microleakage in samples treated with air abrasion, followed by the samples treated with mechanical brushing. The teeth prepared by bur treatment before sealant application show a significant number and degree of marginal infiltration. CONCLUSION: It can be concluded that air abrasion technique is able to guarantee a reliable seal of occlusal surfaces.

Laboratory comparison of a titanium trauma splint with three conventional ones for the treatment of dental trauma.

AIM: This was to evaluate the efficacy of a Titanium Trauma Splint (TTS) by comparing it with three other devices commonly used in the care of dental trauma, a Resin Splint (RS), Button-Bracket Splint (BS) and a Wire- Composite Splint (WCS). METHODS: The four types of splints were applied on experimental dental models, including in the splints the teeth from canine to canine of each maxilla. Two load-tests for each device were applied with the dental model inclined to 45 degrees or less, and increasing forces were applied to the incisal edges from 0N to 50N, in the first test, and from 0N to 100N in the second. At the same time the displacement involved of the splinted teeth was assessed and then the ratio between the two measured sizes was graphically represented. RESULTS: In the level tests the displacements of the splinted teeth caused by the force of 80N were: 0.39 mm for the BS, 0.37 mm for the TTS, 0.35 mm for the WCS and 0.30 mm for the RS. In the inclined tests, the splints under the effect of 40N, showed displacements as: 1.65 mm RS, 1.83 mm BS, 1.89 mm TTS and 2.16 mm WCS. CONCLUSION: With the exception of RS as to rigidity, the other three splints were practically the same in response. Considering other characteristics, the TTS proved to be a promising device for the treatment of dental traumas.