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A case is presented of a patient whose lip became entrapped onto his orthodontic bracket following a blow to his face during a contact sport. The entrapped mucosa had to be released surgically.

The purpose of this study was to investigate whether orthodontic toothbrushes were superior to classical toothbrushes in the elimination of microbial dental plaque on teeth and brackets and in the maintenance of periodontal tissue health in patients, ages 12 to 22 years, with fixed appliances. Twenty patients undergoing orthodontic treatment with fixed appliances and brushing with the Bass technique were included in the study. Ten patients used the Oral B Ortho type toothbrushes (Oral B Laboratories Ltd.), whereas the remaining 10 patients used the Oral B Plus 35 type toothbrushes. Quigley-Hein plaque index, bonded bracket index, sulcus bleeding index, and periodontal pocket depth measurements were made at the beginning of the study and a month later. No statistically significant difference was found for plaque, sulcus bleeding, and periodontal pocket depth between Oral B Ortho and Plus 35 groups when the preinvestigatory and postinvestigatory measurements for the vestibular and proximal surfaces of upper and lower teeth were compared. This short-term study concluded that the Ortho-type toothbrush is not superior to the Plus 35-type toothbrush.

The aim of this clinical study was to test the benefit from using glass ionomer cement (GIC) instead of a conventional diacrylate in bracket bonding for the prevention of white spot formation. Before treatment 7.2 per cent of all examined surfaces (n = 222) were classified as having white spots. No additional fluoride treatment other than fluoride toothpaste was prescribed. At debonding 8-39 months later, white spots were found in 24 per cent of the surfaces bonded with the cement, significantly lower than the 40.5 per cent bonded with the diacrylate (P < 0.01). At recall 12 months after debonding (examined surfaces n = 214) the frequency of surfaces with white spots was reduced to 22 and 24 per cent respectively. Re-examination after a further 12 months (n = 160) showed that white spot surfaces were less frequent with the cement (16 per cent compared with the diacrylate 29 per cent), but still significantly more frequent in both groups than before treatment. With longer treatment time (17 months) teeth bonded with diacrylate were more frequently affected with white spots (P < 0.05). Neither sex nor age affected the results. It is concluded that the use of a GIC for orthodontic bonding will result in a significant reduction in the number of white spot surfaces at debonding compared with the use of conventional diacrylate. Although markedly reduced in both groups, the number of affected surfaces was still higher 2 years after debonding than before treatment.

This study evaluated the clinical performance of a new resin modified glass ionomer cement, Geristore (Den-Mat Corp., Santa Maria, Calif.), for the bonding of orthodontic brackets and its effect on certain caries-associated microorganisms. This cement has been shown to possess increased mechanical properties and long-term fluoride release. There were 716 brackets bonded in 40 patients (17 males and 23 females), with a split-mouth technique and a composite resin, Phase II (Reliance, Itasca, III.), as a control. Bond failures were recorded up to 1 year. Plaque scores and plaque samples were taken from the area of the bonding adhesive in 20 patients, before, at 1 week, and 5 months after the placement of brackets. The plaque samples were investigated for the presence of Streptococcus mutans and lactobacilli. The overall bond failure rate was found to be 8.9% for Geristore and 3.1% for Phase II (p < 0.05). Labially, there was no significant difference (p > 0.05) in bond failure rate: 3.8% for Geristore and 1.7% for Phase II. The proportions of S. mutans and lactobacilli in plaque taken from around Geristore cement were reduced at 1 week and 5 months, when compared with Phase II resin, and this reduction was statistically significant (p < 0.05) at 1 week. Results of this study suggest that Geristore may be of use in the labial segments, especially in caries prone patients, in whom demineralization at debond may present an esthetic and restorative problem several years after treatment.

Enamel demineralization during active orthodontic treatment remains a significant problem. The purpose of this in vitro study was to evaluate the efficacy of applying a light-cured unfilled resin, a conventional pit and fissure sealant, to the labial surface of teeth with previously placed orthodontic appliances to prevent demineralization. Orthodontic brackets were bonded to 40 extracted human teeth with a commercially available orthodontic adhesive. The exposed labial surfaces of 30 teeth (experimental group) were sealed with a clear, light-cured, unfilled resin. The remaining 10 teeth (control group) were left unsealed. Both groups were placed in a demineralization environment, and then all teeth were sectioned and examined under polarized light microscopy for the presence or absence of enamel demineralization. Every member of the control group exhibited demineralization of the entire exposed labial surface, whereas 80% of the sealed teeth exhibited no demineralization. Small, isolated areas of enamel loss were seen in six of the sealed teeth representing "breaks" in the sealant layer. The results of this study indicate that light-cured sealant treatment after orthodontic appliance placement significantly reduces enamel demineralization.

Unaesthetic white spot lesions or larger unsightly areas of decalcification around orthodontic brackets remain a significant problem during fixed appliance treatment. This study determined the in vitro fluoride release from 200 fluoride-containing elastomeric ligature ties. With the potentiometric analytic method, the fluoride release was determined in distilled water, for 10 groups of 20 elastomerics, representing the clinical usage in a patient. Readings were taken every 24 hours for 5 days and then every second week for 6 months. The data were analyzed with the Wilcoxon matched pairs signed ranks test. Fluor-I-Ties (Ortho Arch Company Inc., Hoffman Estates, III.) released significant amounts of fluoride compared with the control readings. The fluoride release was characterized by an initial burst of fluoride during the first day and second day, followed by a logarithmic decrease. By the end of the second week 88% of the total fluoride had been leached from the elastomerics, but adequate magnitudes of fluoride were released over the remainder of the test period to aid theoretically in the prevention of demineralization and enhance remineralization of enamel through calcium fluoride and fluorapatite formation. For optimum clinical benefit, Fluor-I-Ties should be replaced monthly. Future prospective longitudinal clinical studies are indicated.

The presence of decalcification (white spots) after the removal of orthodontic appliances still remains a problem. A method to deliver fluoride to the area beneath and around the bonded attachments, independent of patient compliance, could be very helpful. Therefore special attention is being currently directed to the so-called "fluoride releasing bonding adhesives." A clinical trial was carried out to compare the effect of a visible light-cured fluoride-releasing (F-releasing) material with a chemically cured nonfluoride resin on white spot formation during fixed orthodontic therapy. Fifty patients entered the trial, and 762 brackets were bonded in a crossover design. Intraoral slides were taken before and after treatment and were evaluated for white spot formation. Statistical data analysis was carried out by means of a chi-square test. The results of this clinical study indicate that there was no significant difference between the decalcification rates for both types of adhesives. When the appearance of white spots was evaluated in an overall manner, there was significantly more upper than lower decalcification.

Before the 1970s, Begg and Edgewise appliances were the most commonly used appliances in orthodontics. With the introduction of preadjusted appliances, many have made claims of superiority. These claims are often unsubstantiated, as few, if any, have ever been tested in a controlled, prospective in vivo study. The purpose of this study was to compare the time required to retract canine teeth by using two different preadjusted bracket systems (Tip-Edge, TP Orthodontics, LaPorte, Ind., versus A-Company straight wire, Johnson and Johnson, San Diego, Calif.) in a human sample. Anchorage loss as a result of this movement was also evaluated. A sample of 12 patients was randomly selected from the new patient pool at the postgraduate orthodontic clinic of Montefiore Medical Center. All patients required the removal of first premolars in one or both arches as a part of their orthodontic treatment. The rate of retraction and anchorage loss were evaluated. Paired t tests were performed separately for the rates of retraction and anchorage loss. The mean rates of retraction were 1.88 mm per 3-week period and 1.63 mm per 3-week period for the Tip-Edge and A-Company brackets, respectively. There was no statistically significant difference in the rates (p > 0.05). The mean anchorage loss was 1.71 mm for the Tip-Edge bracket, and 2.33 mm for the straight wire bracket. The difference in the amount of anchorage loss was inconclusive as the sample size was too small (power was 10%).

Fluoride-releasing dental materials are generally believed to reduce or prevent secondary caries. The evidence for this is largely anecdotal and centers on clinical experience with silicate cements and, more recently, with glass-ionomer cements. Unfortunately, corroborating evidence from controlled clinical trials is inadequate to establish precisely how effective these materials are or under what conditions they might be effective. Even less is known about the clinical effectiveness of newer materials that, often, release less fluoride. In vitro model systems have been used to study the effects of dental materials on de/remineralization of surrounding tooth structure. Fluoride-releasing materials have been shown in these models to reduce demineralization of both enamel and dentin compared with a material that does not release fluoride. This is useful from a mechanistic standpoint, but without clinical "standards" to guide model results, it is not possible to define an acceptable level of fluoride release or the length of time such release is required. A limited number of in situ model studies has been conducted, and some fluoride dose-response information has been obtained. These models are closer to the real situation and perhaps provide the best means to define required levels of fluoride release from materials in the absence of adequate clinical information.

Apical root resorption is a serious iatrogenic problem sometimes associated with orthodontic treatment. The Speed appliance (Strite Industries, Ltd., Ontario, Canada) provides a continuous rotatory and torque action through its spring clip mechanism, in contrast with the edgewise appliance that may provide an interrupted force. The effect of continuous action on root resorption compared with the interrupted action of the edgewise system has not been investigated previously. The purpose of the present investigation is to test the null hypothesis that there is no difference in the apical root resorption seen after orthodontic treatment with the edgewise straight wire and the Speed appliance systems. Pretreatment and posttreatment periapical radiographs of 63 patients, (30 treated with the Speed 0.018 bracket and 33 with the 0.018 edgewise bracket) were studied. The long cone paralleling technique was used for all the radiographs. Any image distortion between the pretreatment and posttreatment radiograph was calculated and compensated for by using the crown length measurements, on the assumption that the crown length remains unaltered during the treatment period. Quantitative measurements of crown and root lengths for the maxillary and the mandibular central and lateral incisors were compared. Means and standard deviations for the percentage root resorption per tooth group were calculated. A three-factor analysis for variance (ANOVA test) was performed to determine whether there was an appliance, treatment, or gender effect on the amount of root resorption seen after treatment. No statistically significant difference in root resorption between the two appliance systems was found.(ABSTRACT TRUNCATED AT 250 WORDS)

In the present crossover clinical trial, the plaque-removing efficacy of a counterrotational toothbrush was compared to that of a normal toothbrush in orthodontic patients. Twenty subjects, aged 11 to 26 years, who had orthodontic brackets on all fully erupted teeth of at least one arch were selected. At the first appointment, a prophylaxis was given to bring the plaque score to 0. Ten subjects received counterrotational brushes, and 10 subjects received manual brushes according to a randomized list. At 14 days, plaque scores were recorded and another prophylaxis was given. The subjects who were using the electric brush were assigned to the manual brush and vice versa. At 28 days, plaque scores were reassessed. Results showed that the counterrotational brush was significantly more effective in removing supragingival plaque from bracketed teeth than was the manual brush. The differences in plaque-removing effectiveness were particularly consistent on the proximal surfaces of the teeth.

The effect of an antibacterial varnish (Cervitec) on the levels of mutans streptococci in plaque adjacent to bonded orthodontic brackets was evaluated in 18 children using a split-mouth technique with a placebo varnish control. The test varnish contained 1% chlorhexidine and 1% thymol as active ingredients. Both varnishes were applied on four occasions during a 3-month period, and plaque was subsequently collected between 1 week and 6 months after the onset of treatment. All teeth involved in the study were carefully examined and clinically assessed for enamel demineralization prior to onset of the fixed appliances and immediately after debonding. The results showed a more frequent growth of mutans streptococci in the dental plaque collected from placebo-treated quadrants as compared with the test quadrants on all sampling occasions. The proportion of mutans streptococci within the plaque microflora was significantly (p < 0.05-0.01) lower on the test sides than on the opposite sides at the 1-week and 1-month examinations. The incidence of incipient enamel lesions around the brackets and along the gingival margin was generally low, and no differences were found between the test and placebo varnish treated quandrants at the time of debonding. The results suggest that mutans streptococci in plaque from orthodontic patients can be suppressed effectively by topical applications of an antibacterial varnish.

The effectiveness of fluoride in reduction of caries is well known. This study examined the ability of a fluoride-releasing resin to reduce caries, as well as demineralization around orthodontic brackets, by using the Sprague-Dawley rat as a model. Eighteen-day-old rats were infected with cariogenic Streptococcus sobrinus 6715. After infection was confirmed, standard orthodontic techniques were used to bond miniature orthodontic brackets to the lingual surfaces of maxillary first molars, with either a fluoride-releasing resin (group I) or a conventional resin (group II). A control group was infected but not bonded (group III). Bonding was done at age 34 days. Rats were fed a cariogenic diet and were killed at age 72 days. Lingual surfaces of maxillary first molars were evaluated for area of demineralization, and mandibular molars were scored for caries. Mean percent area of demineralization for group I was 4.7%, for group II 35.7%, and for group III 0%. The difference between groups I and II was statistically significant (p < 0.01). Mean mandibular molar enamel carious lesion unit count for group I was 9.8, for group II 16.3, and for group III 13.7. Group I had significantly fewer lesions than groups II and III (p < 0.01), and group II had significantly more lesions than group III (p < 0.01). These results indicate that a fluoride-releasing resin reduces demineralization at the site of application and reduces caries at distant sites in the experimental rat model.

This study investigates the effects of fluoride-releasing bonding composites on the development of artificially created white spot lesions ex vivo. The severity of the lesions was estimated visually using the von der Fehr Caries Index. The integrated mineral loss of the lesions (delta z) was measured using microradiography/microdensitometry. The results of the visual assessment indicated that teeth bonded with Reliance exhibited more Grade 2 lesions than expected. Teeth bonded with Mirage Dual Cure, however, showed a high prevalence of teeth with no lesions (Grade 0) and few with Grade 2. Microdensitometric analysis found 17 subsurface lesions; 14 of these were in the non-fluoridated groups (Right-On and Heliosit), and 3 and 1 in the fluoridated groups (Reliance and Mirage Dual Cure), respectively. Lesion mineral content ranged from 64.93 to 20.43 per cent for Right-On, from 32.53 to 26.72 per cent for Heliosit, from 19.52 to 19.58 per cent for Reliance, and 23.58 per cent for Mirage Dual Cure. The results of this study suggest that fluoride-releasing composites may have a caries preventive effect around orthodontic brackets.

White spot lesions of enamel around orthodontic brackets as a result of demineralization have been well documented in the orthodontic literature. Various methods of treatment have been attempted to reduce or eliminate this danger. The purpose of this study was to evaluate, by means of scanning electron microscopy, the polymerization of the sealant layer around orthodontic brackets with direct and indirect methods of bonding. Twenty-four sound human lateral maxillary incisor teeth were collected, cleaned, divided equally into four groups A through D, and stored in 70% ethyl alcohol. Their buccal surfaces were pumiced, etched with 37% phosphoric acid for 1 minute, and washed under running water for 30 seconds. Metal brackets were bonded with the chemically cured BIS-GMA resin, Ortho Concise, as follows: group A, indirectly bonded with coping; group B, indirectly bonded without coping; and group C, directly bonded; light activated Transbond was used in group D, directly bonded brackets. After washing in alcohol for 20 seconds, all teeth were dried, and sectioned longitudinally, through the middle of the bracket. All were subjected to 5% hydrochloric acid for 30 seconds and then washed under running water for 30 seconds. After drying and sputter coating, the teeth were viewed under scanning electron microscopy. Groups A and D showed a sealant layer surrounding the brackets and covering the buccal enamel. Groups B and C showed total absence of a cured sealant layer around the brackets or surrounding enamel.(ABSTRACT TRUNCATED AT 250 WORDS)

In the present in vivo study, the cariostatic potential of a titanium tetrafluoride (TiF4) solution applied topically around orthodontic brackets was investigated with quantitative microradiography. Also characteristics of the TiF4-treated enamel surface were examined with scanning electron microscopy (SEM). Ten pairs of premolars to be extracted for orthodontic treatment were used in the first part of this study. Brackets were bonded on all teeth with an orthodontic adhesive, and 10 randomly selected premolars served as controls, whereas a similar number were treated with 1% TiF4 around brackets for 60 seconds. After 4 weeks with no topical fluoride supplementation, all teeth were extracted and stored for analysis. Results indicated the 1% TIF4 solution reduced lesion depths and total mineral loss, at the bracket periphery, significantly during the 4-week period. The presence of a surface coating was demonstrated by SEM micrographs. It was concluded that TiF4 may provide a high level performance as a prophylactic agent for orthodontic purposes.

A clinical trial was undertaken to evaluate the effectiveness of two new enamel sealing systems in the prevention of enamel decalcification following bracket bonding. Eighty patients undergoing fixed appliance therapy were included. Of these, 40 were treated with a viscous chemically-cured sealant and bonding system (Maximum Cure), while 40 patients were treated using a non-viscous visible light-cured sealant and bonding agent (Transbond resin). Alternate teeth were used as controls where no sealant was used. A total of 289 experimental and 282 control teeth were included in the chemically-cured sealant group, the figures for the light-cured sealant group being 306 and 305, respectively. Enamel decalcification incidence and distribution were recorded using a modified index by direct clinical observation. The results showed that 75 per cent of patients were affected by some decalcification. The viscous sealant reduced the extent of decalcification of tooth zones by 13 per cent. The non-viscous sealant produced no significant difference. Over 60 per cent of decalcification occurred in the gingival areas. Maxillary lateral incisors and canines, and mandibular canines and second premolars were the teeth most severely affected, and the most likely to benefit from sealing. Further research is needed to develop a material which provides greater enamel protection.

Light-hardened glass-ionomer-resin restorative cement has all the advantages of glass-ionomer cements and the additional feature of rapid hardening by visible light application. The new restorative formulation can be used to restore a carious lesion adjacent to a bonded orthodontic bracket.

The advantage and disadvantage of applying ceramic orthodontic brackets were compared on base of practical experiences. The application of ceramic brackets is recommended in the clinical practice, considering that also enamel injuries may develop by debonding.

A clinical trial comparing a conventional adhesive, Concise, with a new fluoride-containing composite cement is described. The bond failure rate, plaque score, gingival health, and enamel decalcification were assessed for each material after a minimum period of 1 year. The preliminary results show no significant difference between the two materials for each of the variables examined, although there was a reduction in the number of white spot lesions using the fluoride-containing composite. The level of fluoride ion concentration required to inhibit the growth of oral micro-organisms is discussed.

The purpose of this study was to evaluate in vitro the failure pattern of ceramic brackets bonded to enamel with a light-cured orthodontic adhesive. Five types of ceramic brackets and 125 incisors were used in the study. The brackets were bonded onto enamel with a light-cured orthodontic adhesive. After 1 week storage and thermal cycling, the samples were debonded by one operator according to the individual technique for each bracket group proposed by each manufacturer. The fracture surfaces were examined under a stereomicroscope to reveal the type of failures. The effect of the debonding procedure on enamel structure was significantly affected by the various bonding mechanisms of the bracket bases. Cohesive enamel fractures were detected from brackets that provided a bonding mechanism of micromechanical retention and chemical adhesion. The brackets that combined mechanical retention and chemical adhesion, presented both cohesive resin fractures and fractures located at the bracket resin or the resin enamel interface. The higher frequency of cohesive bracket fractures was obtained from a monocrystalline bracket.

The fluoride concentrations in dental plaque adjacent to orthodontic brackets retained with a glass ionomer cement (GIC) or a resin-based composite were investigated using the split-mouth technique. 48-hour plaque was collected at 3, 8, 28 days and 6 months after the onset of orthodontic treatment. The fluoride content of the plaque samples was determined after a microdiffusion procedure with a fluoride-sensitive electrode. Significantly (p < 0.001-0.05) elevated concentrations of fluoride were found in the plaque samples collected adjacent to GIC-retained brackets compared to plaque sampled from composite-retained brackets on all sampling occasions. The results suggest that GIC-bonded brackets in orthodontic treatment may act as local long-term fluoride-releasing devices.

Orthodontic treatment may in some cases initiate damage to teeth and supporting tissues (decalcification and gingivitis) or root resorption, pulp damage, allergic reactions, or craniomandibular dysfunction. This review updates some interesting findings regarding these problems.

Eight-hundred-and-twenty-two British orthodontists were sent questionnaires regarding their use of ceramic brackets. Five-hundred-and-forty-six (66 per cent) responded, and from these, 512 (62 per cent) were analysed. Approximately half of these operators had experience with ceramic brackets, but only 32 operators had treated more than 30 patients. Clinicians' experiences and problems during treatment and debonding are discussed.

Patient home care during orthodontic treatment is often less than ideal. For those patients who routinely let plaque accumulate around orthodontic appliances, there can be white or stained areas of decalcification around the bonded appliances. Management of this esthetic problem can be accomplished in several ways depending on the severity of the defect. This paper describes the very conservative technique of microabrasion which works well in removing superficial markings caused by decalcification. In a sample of 98 decalcified teeth from 20 patients with orthodontic decalcifications and various other unesthetic stains, microabrasion removed most or all of the disfiguring marks on 78.5 percent of the teeth evaluated. At least some improvement was noted 96.9 percent of the time. These results were statistically significant (P > .01). It seems appropriate to employ this technique prior to initiating more aggressive cosmetic dentistry such as resin bonding, Class V restorations, or labial veneers.

Increasing numbers of patients are being orthodontically treated by specialist and general dental practitioners, after postgraduate courses and clinical assistantships. The potential for iatrogenic damage to the teeth and supporting structures has, therefore, also increased. This paper examines these problems and outlines measures for their prevention.

Orthodontists are now treating patients who are demanding high quality orthodontics which is also aesthetically pleasing. The quest for an aesthetic yet strong appliance has led to many innovative designs. This article summarizes the main advances.

This study was designed to investigate the cariostatic potential in vivo of a visible light-curing adhesive for the bonding of orthodontic brackets. The fluoride release of the adhesive in water and saliva was also measured. Ten orthodontic patients with premolars to be extracted participated. One bracket with Heliosit-Orthodontic (no fluoride) was positioned on the buccal surface of one premolar (control), and another bracket with Orthodontic cement VP 862 (containing fluoride) was positioned on the experimental contralateral premolar. The adhesives were cured with a Heliolux II lamp, and the teeth were extracted after 4 weeks. The patients used a fluoride toothpaste during the experiment. The mineral content of the enamel adjacent to the brackets was determined by quantitative microradiography. The fluoride release from disk-shaped plates of the fluoride adhesive was measured in water for a 6-month period and in human saliva for 24 hours. The fluoride adhesive reduced lesion depths by about 48% than the nonfluoride adhesive (P less than 0.05, t test). The largest release of fluoride from the plates in water was observable within the first week. However, a significant amount of fluoride was still released after 6 months. The fluoride release in saliva was significantly lower in human saliva at pH 7 than in water (P less than 0.01, t test). When salivary pH was lowered to 4, to mimic a cariogenic challenge, the amount of fluoride released increased up to the value measured in water. It was concluded that the regular use of fluoride toothpastes is insufficient to inhibit lesion development around orthodontic brackets.(ABSTRACT TRUNCATED AT 250 WORDS)

Methyl methacrylate-based (MMA-based) bonding resins have been used in orthodontics because they offer easy removal of both the bonded bracket and the residual adhesive at case completion. However, these materials are not cross-linked, and the brackets bonded with this type of product may undergo drifting when subjected to temperatures slightly higher than those in the mouth. This research investigated the influence of heat on the debonding characteristics of a MMA-based bonding resin compared with those of a BIS-GMA-based system. The temperature of initial bracket movement, as well as of final bracket displacement, was noted for a variety of applied loads (141, 226, 425, 934, and 1727 gm) with stainless steel brackets bonded to etched bovine enamel. The results showed that the MMA-based material underwent a glass transition near 47 degrees C in which the initiation of bracket drift resulted on the tooth surface. This temperature proved independent of the applied load. Further heating resulted in the release of heat from the resin as a result of further curing. The extent of bracket drift associated with this secondary heat release was dependent on the applied load. The debonding temperature of the BIS-GMA-based system was three to six times greater than that of the MMA-based product. Practitioners should be aware that brackets bonded with MMA-based resins have the potential for drifting when subjected to temperatures within the normal range of hot fluids consumed by their patients. Bracket drift could result in deactivation of orthodontic force and could prolong the treatment time.

The purpose of the present study was to determine if once daily use of a 1.5% H2O2 rinse with 0.05% NaF was more effective in preventing decalcification in adolescent orthodontic patients than comparable use of a 0.05% NaF rinse without H2O2, or in patients using no rinse at all. Ninety-five subjects were selected consecutively from adolescents scheduled to receive fixed orthodontic treatment on both dental arches. Three groups were formed that were matched in percentages for age and sex. The first group (control group, n = 35) used a 1100 ppm F toothpaste only. The second group (NaF rinse group, n = 30) used both the same toothpaste and a once daily 0.05% NaF rinse. The third group (H2O2-NaF rinse group, n = 30) used the toothpaste and a once daily rinse containing both 0.05% NaF and 1.5% H2O2. Decalcification was assessed single-blind on the facial surfaces of all erupted teeth at baseline (before appliances were placed), and 3 months after fixed appliances were removed. The difference between baseline and post-treatment decalcification levels determined the incidence of decalcification during orthodontic treatment. Since the first molars were found to have the highest decalcification scores, separate analyses of variance were carried out for the whole mouth and first molar assessments. A p value of less than 0.05 was considered statistically significant. The results showed no significant differences between any of the groups before orthodontic treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

The aim of this study was to evaluate the effect of cemented bands and enamel bonded attachments on the gingival health of second molars. In 23 patients the right upper and lower second molars were banded, while the left upper and lower second molars were bonded. The plaque index, the gingival index, and pocket depths were greater and statistically significant on the right side, indicative of increased inflammatory activity where bands were cemented. Once the appliances were removed, both areas returned to pretreatment levels.

In this study we wanted to test the in vitro effects of orthodontic magnetic brackets, developing different magnetic fields, on the oral microbial flora. We noticed that a magnetic field has its most considerable influence on Candida albicans growth; the stimulating response depends on various factors: cell inoculum, exposure time and magnetic field frequency.

Direct bonding of brackets onto the tooth enamel has become a routine procedure in orthodontics. Some detrimental side effects of this technique are described. Most iatrogenic effects are restricted to the enamel and mostly when white spots exist before bonding the brackets. The risk of damage is limited when the etching agent is applied carefully.

The purpose of the present study is to clarify the influence of microflora in plaque of the brackets edge by direct bonding system and the cause of caries that is induced around the bracket during orthodontic treatment. The subjects were selected from the patients undergoing direct bonded orthodontic treatment and from the non-orthodontic patients. They were divided into four groups: those having no orthodontic treatment (control group), those having no caries around the bracket (group A) and those having caries around the bracket (groups B and C). Sample plaques were collected from the initial tooth surface with control group, from the tooth surface around the bracket with group A, from the carious cavity around the bracket with group B and from the non-carious tooth surface around the bracket with group C. The isolation rates of microflora in dental plaque of the four groups were compared, and the following conclusions were obtained. 1. Group A had almost same level with control group as to the proportion of each bacterium examined by shape and gram stain of microbiota. Group B had higher level of gram positive cocci than the other groups. 2. Group A and control group had no difference as to the isolation rates of genera Streptococcus, Actinomyces and Lactobacillus. 3. Group A had low level of S. mutans, was the same as control group. 4. The isolation rate of each genus: 1) The isolation rate of genus Streptococcus was almost same in groups A, C and control group. Group B had higher than the other groups. 2) The isolation rate of genus Actinomyces was the highest in all groups. 3) The isolation rate of genus Lactobacillus was exceedingly low. 4) Groups B and C had significantly higher level of S. mutans group than group A and control group. Group B had significantly lower level of S. mitior than group A and control group. 5. All four groups showed high level of biotype I, and biotype IV was observed in groups B and C. Biotype I was identified as S. mutans serotype c, biotype IV was observed as S. sobrinus serotype d.