Evaluation of pain intensity with prostaglandin E2 biomarker and visual analog scale during initiation of orthodontic treatment: A prospective study

OBJECTIVES

The aim of this study was to assess subjectively and objectively, at which timepoint the patient undergoing fixed orthodontic treatment will have maximum pain during the initiation of orthodontic treatment.

MATERIALS AND METHOD

A total of 22 patients (21 ± 2.7 years, [15 female and 7 male]) requiring extraction of maxillary first premolar participated in the study. Following bonding, an initial archwire of 0.016" NiTi was placed with a distal force of 100 g applied to the canines. The concentration of prostaglandin E2 (PGE2) in the gingival crevicular fluid was assessed at four time points: 1 hour before (T0); 24 hours (T1); 48 hours (T2); 72 hours (T3) after initial archwire placement. The pain intensity was recorded with visual analog scale.

RESULTS

The concentration of PGE2 increased from T0 to T1. The highest concentration was observed at T2 following which there was a mild decline at T3. Statistically significant difference in the PGE2 concentration was observed between T0 to T1 and T1 to T2. The visual analogue scale (VAS) scores increased from T0 to T1. The highest score was observed at T2 followed by a decline at T3. A statistically significant difference in the VAS score was noted between T0 to T1 and T2 to T3. On correlating PGE2 and VAS score, a weak negative correlation was noted between T0 to T1 and no correlation was noted between T1 to T2 and T2 to T3.

CONCLUSION

The patients experience maximum pain between 24 hours (T1) and 48 hours (T2) following initial archwire placement. The highest concentration of PGE2 and VAS score was observed at 48 hours (T2).

Alveolar Bone and Gingival Changes in Mandibular Anterior Region Following Herbst Appliance Therapy: A Systematic Review and Meta-analysis

Objective

To assess the alveolar bone changes and gingival recession following Herbst appliance therapy.

Materials and methods

Electronic databases such as PubMed, Ovid, Cochrane Library, Lilacs, Scopus, Web of Science, and Embase were searched until August 2022. Hand-searching of major orthodontic journals was performed to identify all peer-reviewed articles potentially relevant to the review. The quality of the selected studies was ranked using the revised Cochrane risk of bias tool for nonrandomized trials-Risk of Bias In Nonrandomized Studies (ROBINS) 1.

Results

Five relevant articles (all nonrandomized studies) were considered for qualitative analysis. The risk of bias was low for four studies and moderate for one. The reduction in the vertical alveolar bone height was 0.13 ± 0.07 mm, with the Herbst appliance. The mean difference in the loss of buccal cortical thickness between the Herbst appliance and untreated control group was 0.22 mm [95% confidence interval (CI) of -0.62-0.18]. Subsequent to Herbst appliance therapy, in the mandibular anterior region 0.1 ± 0.5 mm of gingival recession was observed.

Conclusion

Herbst appliance treatment produces a negligible reduction in the buccal cortical thickness, vertical alveolar bone height, and gingival recession.

Clinical significance

Though the changes produced by the Herbst appliance were minimal, they are clinically important considering the young age of the patients warranting periodic periodontal assessment.

How to cite this article

Kumar MV, Kannan A, Kailasam V. Alveolar Bone and Gingival Changes in Mandibular Anterior Region Following Herbst Appliance Therapy: A Systematic Review and Meta-analysis. Int J Clin Pediatr Dent 2024;17(1):114-120.

Effectiveness of Functional Mandibular Advancer in Patients with Class II Malocclusion: A Systematic Review and Meta-analysis

Objective

We aimed to evaluate the effectiveness of functional mandibular advancer (FMA) in treating growing patients with Class II malocclusion.

Methods

Electronic searches were conducted in MEDLINE (via PubMed), Cochrane Library, Web of Science, Scopus, Embase, and Lilacs from 1945 to 30th November 2021. Studies were selected based on the following inclusion criteria: human studies, Class II growing patient treated with FMA, untreated control group or a comparable group treated with another fixed functional appliance, pre- and post-treatment lateral cephalograms/magnetic resonance imaging/cone-beam computed tomography, randomized clinical trials, prospective studies, and retrospective studies. Data extraction of the included articles was independently performed independently by two authors. The risk of bias was assessed using the ROBINS-I tool. Meta-analysis was performed using the inverse generic model.

Results

Seven articles met the criteria and were included in the systematic review and three articles were included in the meta-analysis. Three studies had at low risk of bias and four studies had a moderate risk of bias. All articles reported anterior positioning of the mandible along with an increase in mandibular length. The meta-analysis results indicated a negligible difference between FMA and other functional appliances for the parameters SNA [0.11, 95% confidence interval (CI) of -1.07 and 1.29] and ANB (-1.00, 95% CI of -1.34 and -0.65). The evidence was limited for soft tissue changes.

Conclusion

Class II correction with FMA involved a combination of skeletal and dentoalveolar changes and was similar to other fixed functional appliances.

The Evaluation of Maxillary Sinus Dimensions in Different Craniofacial Patterns: A Systematic Review and Meta-Analysis

This systematic review was intended to evaluate the maxillary sinus dimensions in vertical and sagittal craniofacial patterns and to assess if there was a difference among the craniofacial patterns. A systematic search was performed in seven databases till February 2021. The risk of bias was performed with modified Newcastle Ottawa scale. Meta-analysis was performed using random effects model. Twelve studies were included in the review and 8 in the meta-analysis. Compared to Class I malocclusion, the maxillary sinus area is greater in Class II and lesser in Class III malocclusion. On comparing normo-divergent growth pattern, the maxillary sinus area is lesser in hypo-divergent and greater in hyper-divergent individuals. Most of the studies were graded as satisfactory. The measurements are greater in hyper-divergent Class II malocclusion and in males.

Antimicrobial efficacy of zinc oxide nanoparticle-coated aligners on Streptococcus mutans and Candidaalbicans

INTRODUCTION

This study aimed to assess the antimicrobial effect of zinc oxide (ZnO) nanocoating on aligners.

METHODS

Twenty-six samples of aligners were sputter-coated with ZnO nanoparticles and compared with 26 uncoated samples. The antimicrobial effect was assessed on Streptococcus mutans and Candida albicans. The thickness of the ZnO coating was standardized at 100 nm. The antimicrobial effect was evaluated for 7 days at the following time points: 6 hours, 12 hours, first day, second day, fourth day, and seventh day. Colony culture tests were performed for microbial evaluation.

RESULTS

ZnO-coated aligners showed significant antimicrobial efficacy against S mutans at all time points tested (P <0.001). The antimicrobial effect was observed up to 2 days after a decline. The activity against C albicans was minimal at all time points, and no statistical significance was observed (P >0.05).

CONCLUSIONS

ZnO-nanocoated aligners were effective against S mutans, with the maximum antibacterial effect observed until 2 days and lasting for 7 days. The effect against C albicans was minimal. ZnO-coated aligners appears to be a promising technique to facilitate antimicrobial efficacy against S mutans.

Cranial Base Angle in Patients With Cleft Lip and Palate-A Systematic Review and Meta-Analysis

Background: Diverse findings have been reported for the cranial base angle (CBA) in patients with CLP (cleft lip and palate) and non-CLP controls. Objective: The aim of this study is to assess and evaluate the CBA in patients with CLP and non-CLP controls. Methods: Data from PubMed, OVID Technologies, Inc., Cochrane, Literatura Latino-Americana e do Caribe em Ciências da Saúde (LILACS), Scopus, Web of Science, and EMBASE for Excerpta Medica dataBASE (EMBASE) with relevant terms was extracted until December 31, 2020. Inclusion criteria were data of patients with non-syndromic unilateral cleft lip and palate (UCLP) and bilateral cleft lip and palate (BCLP). In the case of UCLP and BCLP, patients with craniofacial syndromes were excluded. The study proposal was registered with PROSPERO (Registration number: CRD42021228632). Results: Fifteen studies with a total of 2032 participants were included for the systematic review and 14 studies with a total of 1972 participants were included for the meta-analysis. The risk of bias was assessed using the Modified Newcastle Ottawa scale under seven domains by two authors. Thirteen studies were graded as "good" and two as "satisfactory." The CBA in patients with CLP were greater than the non CLP Class I controls in six of the 15 studies. CBA was greater in patients with CLP than non-CLP controls by 1.21° (95% CI of 0.19-2.22). Meta-analysis reported considerable heterogeneity (I² = 86%). Anterior (ACB) and posterior cranial base (PCB) lengths were shorter in patients with CLP than in the non-cleft Class I controls by 2.14 mm (95% CI of 0.99-3.30) and 2.06 mm (95% CI of 1.52-2.60), respectively. Conclusion: Most studies were graded as good. Patients with CLP had greater CBA and shorter ACB and PCB lengths when compared to non-CLP controls.

The effect of active oxygen-containing toothpaste on Streptococcus mutans and white spot lesions: An in-vivo randomized controlled trial

INTRODUCTION

Fixed appliances limit patients' ability to clean their teeth, thus making orthodontic patients highly susceptible to developing white spot lesions (WSLs). Using patient compliance would be one of the simplest methods to prevent WSLs.

METHODS

A parallel trial design with 34 patients that met the eligibility criteria were randomized to experimental (received Blue M oxygen for health toothpaste) and control (received Colgate Total fluoridated toothpaste) groups. The eligibility criteria were that the patients should be aged 13-30 years, on fixed mechanotherapy, had undergone therapeutic extraction of all first premolars, had completed leveling and aligning, and had satisfactory oral hygiene (assessed using pretreatment and current Simplified Oral Hygiene Index scores). The objectives were to assess the effects of active oxygen-containing toothpaste on Streptococcus mutans (SM) and WSLs in patients undergoing fixed mechanotherapy. The random allocation sequence was generated using the RAND function in Microsoft Excel. The sequence generated was sealed in opaque white envelopes. The investigators and the participants were blinded until allocation. Blinding of the first author (J.A.G.) who dispensed the toothpaste or the participants was not possible. The outcome assessment was blinded by coding the plaque specimens sent for real-time polymerase chain reaction (RT-PCR) to ensure that the final data assessment was blinded. The study setting was the Department of Orthodontics and Dentofacial Orthopedics, Sri Ramachandra Institute of Higher Education and Research (SRIHER) University. The primary outcome was SM counts, which were analyzed using RT-PCR. The secondary outcome was WSL assessment, performed using DIAGNOdent and International Caries Detection and Assessment System (ICDAS) II criteria at baseline and after 4 weeks. The data were subjected to statistical analysis.

RESULTS

Thirty-four patients were randomized to 17 per group and analyzed. RT-PCR showed lower SM in the experimental group (Ct = 32.25 ± 10.6) than in the control group (Ct = 30.9 ± 10.49). However, this was not statistically significant (P = 0.70). ICDAS scores remained the same from baseline and after 4 weeks for both groups. The DIAGNOdent values were in tandem with the ICDAS scores and showed minimal change for the 2 groups (P >0.05). A strong positive correlation was observed for DIAGNOdent and ICDAS scores (τb >0.30). No harms or adverse effects were observed or reported by the patients during the experimental period.

CONCLUSIONS

The active oxygen-containing toothpaste showed a greater inhibitory effect on SM than the fluoridated toothpaste. However, this effect was minimal. Both kinds of toothpaste showed negligible effects on WSLs. Thus, active oxygen-containing toothpaste is as effective as fluoridated toothpaste.

REGISTRATION

The Trial was registered in the Controlled Trials Registry India (CTRI/2021/10/037458).

PROTOCOL

The full protocol can be obtained from any of the authors via e-mail.

FUNDING

The project was self-funded.

Modified OXIS classification for primary canines

Background: A new classification called OXIS was proposed for categorising the interproximal contacts of primary molars, and its prevalence was established. The aim of this study was to establish the variations in interproximal contacts of primary canines and thereby modify the OXIS classification of primary molars to primary canines. Additionally, we aimed to estimate the applicability of modifications to primary anterior teeth.

Methods: A retrospective study was conducted with sectional die models obtained from a previous study of 1,090 caries-free children. Two calibrated examiners evaluated a total of 4,674 contacts from the occlusal aspect. The contacts were scored according to the former OXIS classification, with two modifications incorporated to encompass the morphological differences and rotations of primary canines and other primary anterior teeth.

Results: The most prevalent contact was O (62.1%), followed by X (19.6%), I (12.6%), S type I (4.1%), and S type II (1.6%). Inter-arch comparison by means of the Chi-square test revealed significant differences for all types of contacts ( P < .001).

Conclusions: The interproximal contacts of canines were categorised as O, X, I, S I, and S II. The OXIS classification of primary molars was modified to befit the variations in primary canines. This study showed the presence of different types of contacts in primary canines. Identification of these contacts and their complexity has warranted a need for this to be studied as an inherent risk factor for caries risk assessment.

Long-term hard and soft tissue response following isolated genioplasty: a systematic review

PURPOSE

Genioplasty facilitates alteration of the chin position and contour which contributes to aesthetics and function. The response of the hard and soft tissues following genioplasty has not been assessed after a year or more of the surgery being performed. Hence, the aim of this systematic review was to assess the response of the hard and soft tissues occurring at least 1 year after the procedure.

MATERIAL AND METHODS

A literature search was conducted in the following electronic databases: PubMed, Ovid, LILACS, and Cochrane Library. Potential articles were identified wherein only studies with genioplasty performed as an isolated procedure and with data at least 12 months after the procedure were included.

RESULTS

Five studies were included in this systematic review. Two of the articles included were considered to be of good quality while three were considered to be of moderate quality using a modified Downs and Black tool. The ROBINS-I tool showed a moderate risk of bias for most domains. The study characteristics revealed varying degrees of relapse for the hard and soft tissues.

CONCLUSIONS

In the anteroposterior plane, the soft tissue relapsed more than the hard tissues 3 years post genioplasty. However, relapse in the vertical plane showed a wide variation for both the hard and soft tissues. In the anteroposterior plane, the hard tissue to soft tissue response 2 years or more following genioplasty ranged from 1:0.77 to 1:0.91 while in the vertical plane the hard tissue to soft tissue response ranged from 1:0.67 to 1:1.16.

Modified OXIS classification for primary canines

Background: A new classification called OXIS was proposed for categorising the interproximal contacts of primary molars, and its prevalence was established. The aim of this study was to establish the variations in interproximal contacts of primary canines and thereby modify the OXIS classification of primary molars to primary canines. Additionally, we aimed to estimate the applicability of modifications to primary anterior teeth. Methods: A retrospective study was conducted with sectional die models obtained from a previous study of 1,090 caries-free children. Two calibrated examiners evaluated a total of 4,674 contacts from the occlusal aspect. The contacts were scored according to the former OXIS classification, with two modifications incorporated to encompass the morphological differences and rotations of primary canines and other primary anterior teeth. Results: The most prevalent contact was O (62.1%), followed by X (19.6%), I (12.6%), S type I (4.1%), and S type II (1.6%). Inter-arch comparison by means of the Chi-square test revealed significant differences for all types of contacts (P < .001). Conclusions: The interproximal contacts of canines were categorised as O, X, I, S I, and S II. The OXIS classification of primary molars was modified to befit the variations in primary canines. This study showed the presence of different types of contacts in primary canines. Identification of these contacts and their complexity has warranted a need for this to be studied as an inherent risk factor for caries risk assessment.

Collum angle of the anterior teeth: A systematic review and meta-analysis

OBJECTIVES

To assess and evaluate the collum angle (CA) of the anterior teeth of the permanent dentition.

METHODS

A search in seven databases for articles that had measured the CA in sagittal malocclusions was conducted until November 30, 2021. The risk of bias was assessed using the Modified Newcastle Ottawa scale. CA measurements using Cone Beam Computed Tomography or lateral cephalograms were included. The CA data were summarized by random-effects inverse generic meta-analyses.

RESULTS

Qualitative analysis of the 17 selected articles revealed that four were rated as "very good," 12 as "good" and 1 as "satisfactory." CA was 4.7° (95% CI of 3.1 to 6.4) and 2.0° (95% CI of 0.1 to 3.9) greater in Class II division 2 and Class III malocclusions respectively, than in Class I malocclusion cases.

CONCLUSION

Majority of the studies were rated as good or very good. Most studies evaluated the CA of the maxillary central incisors in Class II division 2 malocclusion. Studies assessing other maxillary anterior and mandibular anterior teeth are required.

CLINICAL SIGNIFICANCE

Practice of esthetic dentistry for teeth with increased CA is of clinical importance since the angle would determine the longevity and esthetic/cosmetic success of the rehabilitation. Placement of dental implants in areas of missing teeth with increased collum angle leads to excessive stress between the fixture and abutment leading to gingival recession. Thus, knowledge about the collum angle of anterior teeth and its variations in sagittal malocclusions would enable precise treatment planning in the field of esthetic dentistry.

Radiographic predictors of maxillary canine impaction in mixed and early permanent dentition - A systematic review and meta-analysis

BACKGROUND/OBJECTIVE

Early diagnosis and the interception of potential impaction is the most desirable approach for management of impacted canines. Several radiographic predictors have been previously proposed to predict canine impaction. Hence the aim of this systematic review was to identify the most effective radiographic predictors of maxillary canine impaction.

SEARCH METHOD

The following databases were searched: PubMed via Medline, Science Direct, LILACS, Cochrane library and Ovid MEDLINE. All comparative studies including observational and interventional studies that compare a canine impacted group versus a control group were included. The primary outcome assessed were the radiographic predictors used for diagnosis of maxillary canine impaction.

RESULTS

Thirteen articles were included in this systematic review. The most commonly used parameters are sector classification, angle formed by the long axis of the canine and the midline, angle formed by the long axis of the canine and the lateral incisor, angle formed by the long axis of the canine and the occlusal plane, and perpendicular distance between the canine cusp tip to the occlusal plane and to the midline. Meta-analysis indicated that the angle formed by the long axis of the canine and the midline with a value of 19.9° and above (95% CI of 6.68 to 33.15), the angle formed by the long axis of the canine and the lateral incisor with a value of 20.01° and above (95% CI of 7.52 to 32.51) favoured canine impaction.

CONCLUSIONS

With eleven of the thirteen articles showing a low risk of bias/good quality, it can be concluded that canine impactions can be predicted using various linear and angular parameters measured on different radiographs (orthopantomograms, lateral cephalograms, postero-anterior cephalograms and cone-beam computed tomography). However, further three-dimensional studies are required to accurately predict and diagnose canine impactions.

REGISTRATION

The study protocol was registered on the International Prospective Register of Systematic Reviews (Reg no: CRD42020200518).

Proximal enamel thickness of the permanent teeth: A systematic review and meta-analysis

INTRODUCTION

This systematic review aimed to identify, evaluate, and provide a synthesis of the available literature on the proximal enamel thickness (PET) of permanent teeth.

METHODS

The eligibility criteria were studies that assessed the PET of the permanent teeth. A search of studies in Medline (via PubMed), the Cochrane Library, Scopus, Web of Science, Embase, and Lilacs databases that measured PET was conducted until August 31, 2020. Two reviewers independently selected the studies, extracted the data, and assessed the risk of bias for systematic reviews involving cross-sectional studies. The quality of evidence was assessed using the Grading of Recommendations, Assessment, Development, and Evaluations approach. PET data generated from the systematic review were summarized by random-effects inverse-generic meta-analysis.

RESULTS

From 1388 potentially eligible studies, 11 were considered for systematic review and meta-analysis. The measurement of PET was done with radiographs, microscopes, microtomographs, or profilometers. In total, 4019 mesial and distal surfaces involving 2118 teeth were assessed. All included studies showed low to moderate risk of bias, whereas GRADE revealed that the level of evidence was low. Greater mesial and distal enamel thickness was observed for the premolars and molars, whereas it was least for the mandibular central incisors. The least difference of 0.02 mm (95% confidence interval [CI], -0.07 to 0.11 and -0.06 to 0.09, respectively) between mesial and distal sides was observed for the maxillary and mandibular second molars, whereas the maximum difference of 0.12 mm (95% CI, 0.07-0.17 and 0.07-0.16, respectively) was observed for the maxillary central incisors and maxillary first premolars. The meta-analysis indicated a moderate level of heterogeneity (I² of 45%). The funnel plot revealed minimal publication bias.

CONCLUSIONS

The summary effect of the meta-analysis revealed that the thickness of the enamel on the distal aspect was greater than on the mesial aspect by an average of 0.10 mm (95% CI, 0.09-0.12). This finding would be of relevance to all disciplines of dentistry and especially for the clinician planning interproximal reduction, a procedure that is routinely done for clear aligner therapy.

Effect of sandblasting on the shear bond strength of recycled metal brackets: A systematic review and meta-analysis of in-vitro studies

INTRODUCTION AND OBJECTIVE

Sandblasting is an efficient and economic method of rebonding brackets. Literature is divided regarding the Shear Bond Strength (SBS) associated with sandblasted brackets. Hence this systematic review was conducted to obtain conclusive evidence on the same. The aim was to compare the SBS between sandblasted brackets bonded to extracted human teeth and new brackets bonded on extracted teeth that have not been previously bonded.

MATERIALS AND METHODS

The following databases were searched up to April 30, 2021: PubMed via Medline, Web of Science, LILACS, Cochrane, EMBASE and Scopus. Articles comparing SBS of a new bracket with that of a rebonded bracket following sandblasting were included. Two reviewers independently selected the studies, extracted the data and assessed the risk of bias which was based on a modification of the Risk Of Bias In Nonrandomized Studies of Interventions Tool (ROBINS-I). SBS data generated from the systematic review was summarized and a meta-analysis using random effects inverse-generic model was done.

RESULTS

Sixteen studies generated 521 samples for the new bracket group and 391 samples for the sandblasted group. These sixteen studies showed a low risk of bias. Meta analysis reported the mean difference between the SBS of new and sandblasted brackets to be 0.85. (95 CI of -0.24 to 1.94). This difference can be clinically disregarded. The high degree of heterogeneity indicated by an I² of 87% led to a subgroup analysis.

CONCLUSIONS

With the studies showing a high quality of evidence, it can be concluded that sandblasting is an efficient means of recycling debonded brackets without affecting SBS. The inherent deficiencies of in vitro bond strength studies should be borne in mind when making this conclusion. The study protocol was registered on the International Prospective Register of Systematic Reviews (Reg no: CRD42020193616).

Effects of haemostatic agents on bond strength - An In Vitro study

Aim

To evaluate and compare the effect of contamination with haemostatic agents like Tranexamic Acid (TA) and Ethamsylate, on the shear bond strength.

Materials and Methods

There are about 100 extracted human premolars randomly segregated into four groups each consisting of 25 samples. Group I was bonded with Transbond, Group II was bonded with Transbond after blood contamination, while groups III and IV were bonded with Transbond after contamination with Tranexamic acid and the shear bond strength was measured. The data were compared by One- way ANOVA and Tukey (HSD) tests.

Results

Group I had the highest shear bond strength (SBS) while Group II, where the teeth were contaminated with blood showed the least SBS values ANOVA indicated significant differences between the four groups (P < .05). Tukey HSD revealed that contamination with TA (Group III) had a statistically higher SBS that contamination with Ethamsylate (Group IV) (P < .05).

Conclusion

Since tranexamic acid and ethamsylate reduces the bleeding when used during surgery, these haemostatic agents may be considered in bonding situations where blood contamination is anticipated.

Comparison of the collum angle of incisors and canines in skeletal malocclusions - A CBCT study

INTRODUCTION

The collum angle that defines the crown root angulation of the single rooted teeth plays an important in treatment planning.

OBJECTIVE

To compare the collum angle (crown root angulation) of maxillary and mandibular anterior teeth in different skeletal malocclusions using Cone Beam Computed Tomography (CBCT).

MATERIALS AND METHODS

Sixty subjects were categorized into four groups (fifteen subjects in each group) Class I, Class II division 1, Class II division 2 malocclusion and Class III based on Angle classification, Wits and ANB. The collum angle of maxillary and mandibular anterior teeth was measured using CBCT. One way ANOVA, Post hoc comparison with Tukey HSD and Paired t-test were used to analyse the measured data.

RESULTS

The collum angle of corresponding right and left side teeth were averaged. Thus, the mean and standard deviation of the collum angle (n-30) were generated for maxillary and mandibular central incisors, lateral incisors, and canines. A statistically significant increase was observed in the maxillary central incisors of Class II division 2 and mandibular lateral incisors of class III malocclusion. The collum angle was increased in mandibular canines of Class III malocclusion when compared with class I and Class II division 2 malocclusion. The collum angle was negative in mandibular central incisors of Class II division 2. No statistically significant difference was observed in the mean collum angle between the right and left side anterior teeth in all the four groups.

CONCLUSION

A variation in Collum angle was observed between the maxillary and mandibular anterior teeth and malocclusions. The effect of these variations in collum angle in torque expression and biomechanics should be kept in mind by the orthodontist before treatment planning especially in Class II division 2 malocclusion.

Evaluation of titanium dioxide coating on surface roughness of nickel-titanium archwires and its influence on Streptococcus mutans adhesion and enamel mineralization: A prospective clinical study

INTRODUCTION

This research aimed to evaluate the effect of titanium dioxide (TiO₂) coating on surface roughness (R_a) of nickel-titanium (NiTi) archwires and its influence on Streptococcus mutans (S mutans) adhesion and enamel mineralization at the end of 1 month in orthodontic patients and to evaluate the integrity of the TiO₂ coating.

METHODS

Twelve patients undergoing orthodontic treatment with preadjusted edgewise appliance formed the sample for this prospective clinical study. Uncoated NiTi archwires and TiO₂ nanoparticle coated NiTi archwires in as-received condition and after 1 month of intraoral use were subjected to R_a analysis using surface profilometry, and surface topography using scanning electron microscopy. S mutans adhesion was evaluated on the retrieved archwires using real-time polymerase chain reaction (PCR). Enamel mineral content in the arches related to the uncoated and coated archwires was evaluated using DIAGNOdent.

RESULTS

After 1 month of intraoral use, both coated and uncoated archwires exhibited a rougher surface with coated archwires demonstrating greater quantum of increase (control, P = 0.002; experimental, P = 0.002). S mutans adhesion was more in uncoated archwires (P = 0.0005). The TiO₂ nanoparticle coating on the NiTi archwires showed delamination, deterioration and was lost by 60% at the end of 1 month. Laser fluorescence values did not show any significant difference (control, P = 0.182; experimental, P = 0.105).

CONCLUSIONS

TiO₂ nanoparticle coating on NiTi archwires causes an initial reduction in roughness; however, at the end of 1 month, the benefit was lost. S mutans adhesion was lesser on the coated wires, which could be attributed to reduced initial R_a and antibacterial property of TiO₂. Orthodontic archwire appears to have a limited role in enamel demineralization.

Evaluation of leptin concentration in Gingival Crevicular Fluid (GCF) during orthodontic tooth movement and its correlation to the rate of tooth movement

OBJECTIVES:

Leptin, a polypeptide which is related to body fat regulation, is also found to have a role in the inflammatory reaction. The aim of this study is to assess the concentration of leptin in Gingival Crevicular Fluid (GCF) during orthodontic force application and to correlate its concentration to rate of tooth movement.

METHODS:

Twenty orthodontic patients (10 males and 10 females) were selected for the study. Leptin concentration was measured at T0, before force application; T1, one hour after force application; T2, one day after force application; T3, one week after force application; T4, one month after force application. GCF was collected using filter paper strips from the distal aspect of gingival sulcus of the right maxillary canine distalized by an active lace-backs of tooth movement was measured on dental casts, before and one month after force application. One-way ANOVA with Bonferroni correction and Pearson's correlation test were used to analyze the data.

RESULTS:

The mean GCF leptin concentration increased from T0 to T1, rose to a peak at T2, then declined to a minimum value at T3 and then increased to a value at T4, closer to the base line value (T0), and it was statistically significant (P < 0.05). There was positive correlation of the overall mean leptin concentration to rate of tooth movement (correlation coefficient = 0.634).

CONCLUSION:

There was a biphasic change in GCF leptin concentration during one cycle of orthodontic force application. There was a positive correlation between the GCF leptin concentration and rate of tooth movement.

Lip response to incisor movement in operated cleft lip and palate patients

BACKGROUND

Although the literature has shown that the lip response to maxillary incisor retraction varies, these studies have been done on a noncleft lip/palate sample.

AIM

The aim of this study is to evaluate response of operated cleft lip to orthodontic tooth movement and to determine if there are any differences in the response between the operated cleft lip and the noncleft lip.

SETTINGS AND DESIGN

This was a hospital-based retrospective study using radiographs.

MATERIALS AND METHODS

Lip changes were evaluated using pre- and post-operative lateral cephalometric radiographs. The experimental group consisted of 12 patients with operated cleft lip while the control group consisted of 12 noncleft patients with dental and skeletal Class I malocclusion.

STATISTICAL ANALYSIS

ANOVA was used for statistical analysis.

RESULTS

The operated lip responded less to incisor movement than the noncleft group (P < 0.05). While the cleft group demonstrated an increase in upper lip thickness measurements at Point A and vermilion following incisor retraction, the control group showed a decrease in thickness of the upper lip at Point A and an increase at vermilion.

CONCLUSION

The cleft team should be aware that the operated lip responds differently to incisor movement. This will enable them to better plan comprehensive treatment for the cleft lip and palate patient.

Streptococcus mutans adhesion on nickel titanium (NiTi) and copper-NiTi archwires: A comparative prospective clinical study

OBJECTIVES

To compare the adhesion of Streptococcus mutans to nickel titanium (NiTi) and copper-NiTi (Cu-NiTi) archwires and to correlate the adhesion to surface characteristics (surface free energy and surface roughness) of these wires.

MATERIALS AND METHODS

A total of 16 patients undergoing orthodontic treatment with preadjusted edgewise appliances were included in the study. 0.016" and 0.016" × 0.022" NiTi and Cu-NiTi archwires in as-received condition and after 4 weeks of intraoral use were studied for S mutans adhesion using real-time polymerase chain reaction. Surface roughness and surface free energy were studied by three-dimensional surface profilometry and dynamic contact angle analysis, respectively.

RESULTS

S mutans adhesion was more in Cu-NiTi archwires. These wires exhibited rougher surface and higher surface free energy when compared to NiTi archwires.

CONCLUSIONS

S mutans adhesion, surface roughness, and surface free energy were greater in Cu-NiTi than NiTi archwires. Surface roughness and surface free energy increased after 4 weeks of intraoral exposure for all of the archwires studied. A predominantly negative correlation was seen between the cycle threshold value of adherent bacteria and surface characteristics.

Bisphenol A release from orthodontic adhesives and its correlation with the degree of conversion

INTRODUCTION

Our objective was to quantitatively assess and compare the bisphenol A (BPA) released from an orthodontic adhesive using a light-emitting diode device (LED) or a halogen light-curing unit (HLC) at 3 tip-to-bracket distances (0, 5, and 10 mm) and varying curing times using high-performance liquid chromatography. BPA release with self-etching and moisture-insensitive primers with light-cured and chemically cured composites was also evaluated. BPA release was correlated to the corresponding degree of conversion.

METHODS

Our sample consisted of 598 stainless steel first premolar brackets. Of these, 520 were used for assessing BPA release and divided into 13 groups of 40 each. In groups I, II, and III, the composite was cured with the LED for 20 seconds at distances of 0, 5, and 10 mm, respectively. Groups IV, V, and VI were cured with the HLC for 40 seconds at the same 3 distances. Groups VII and VIII were cured for 5 and 10 seconds with the LED, and groups IX and X were cured for 10 and 20 seconds with the HLC at 0-mm distance. Groups XI, XII, and XIII consisted of brackets bonded with a self-etching primer and Transbond (3M Unitek, Monrovia, Calif), with a moisture-insensitive primer and Transbond, and with a chemically cured composite. The remaining 78 brackets were also divided into 13 groups and used for assessing the degree of conversion.

RESULTS

The LED devices demonstrated significantly less BPA release and greater degrees of conversion (P <0.05). For both units, BPA release increased and the degree of conversion decreased as the tip distance increased and curing time decreased. The chemically cured group showed significantly less BPA release (P <0.05). Among the light-cured composites, those cured according to the manufacturers' recommendations (40 seconds and 0-mm distance for the HLC unit) released less BPA than did the self-etching primer and the moisture-insensitive primer. The degree of conversion was greatest for the chemically cured composite, whereas it was similar for the conventional, self-etching primer, and moisture-insensitive primer groups. However, correlations ranged from strongly negative to weakly positive between BPA release and degree of conversion.

CONCLUSIONS

Clinicians should consider using LEDs in clinical practice and should keep the light-cure tip as close to the bracket as clinically possible. Curing time should be according to the manufacturer's recommendations. These steps will ensure less BPA release and a greater degree of conversion. Since chemically cured composites had less BPA release and a greater degree of conversion, they can be considered superior to light-cured composites in this aspect.

Rare Complications in Orthodontics--A Case Report and a review

Though perceived as comparatively risk free, orthodontic treatment being a medical intervention has its own share of risks and complications. This case report illustrates an incident of a palatal fistula being observed during fixed appliance treatment in an otherwise healthy individual. Most standard complications are well known, however, some very rare complications like ingestion, infection, blindness and paresthesia have also been reported in the literature and hence a review of rare complications has been attempted. The palatal fistula could have been a coincidence but the orthodontic fraternity should be well advised to look closely at the palate and be aware of rare complications before commencing treatment.

Rapid maxillary canine retraction by dental distraction: A clinical study

AIM

The aim of this clinical study was to perform rapid maxillary canine retraction through distraction of the periodontal ligament and investigate the rate and amount of canine retraction, amount of anchor loss, the nature of tooth movement achieved, and radiographic changes in the periodontal ligament region during and after canine distraction.

MATERIALS AND METHODS

This study was conducted on 10 distractions ranging in age from 14 years to 25 years who needed canine retraction and first premolar extraction in the maxillary arch. Ten canine distractions were carried out with custom-made, tooth-borne intra-oral distraction device.

RESULTS

The results indicate that the periodontal ligament can be distracted just like the mid-palatal suture in rapid palatal expansion and the maxillary canines are retracted rapidly into the first premolar extraction space at the rate of about 2.53 mm/week.

CONCLUSION

Though this study indicates that the periodontal ligament can be distracted to elicit rapid tooth movement, the long-term effects of canine distraction are not well known and need close monitoring.

Sella turcica-Its importance in orthodontics and craniofacial morphology

The sella turcica is a structure which can be readily seen on lateral cephalometric radiographs and sella point is routinely traced for various cephalometric analyses. The search was carried out using the following key words (sella turcica, bridging of sella, size, shape of sella turcica) and with the following search engine (Pubmed, Cochrane, Google scholar). The morphology is very important for the cephalometric position of the reference point sella, not only for evaluating craniofacial morphology, but also when growth changes and orthodontic treatment results are to be evaluated. This makes it a good source of additional diagnostic information related to pathology of the pituitary gland, or to various syndromes that affect the craniofacial region. Clinicians should be familiar with the normal radiographic anatomy and morphologic variability of this area, in order to recognize and investigate deviations that may reflect pathological situations, even before these become clinically apparent. During embryological development, the sella turcica area is the key point for the migration of the neural crest cells to the frontonasal and maxillary developmental fields. The neural crest cells are involved in the formation and development of sella turcica and teeth. The size of sella turcica ranges from 4 to 12 mm for the vertical and 5 to 16 mm for the anteroposterior dimension. There are many classification systems regarding the shape of sella turcica. Majority of the studies show that about 67% of the subjects had normal appearance and about 33% showed variations. The prevalence of sella turcica bridging is high in class III malocclusions and dental anomalies.

Bisphenol A release from an orthodontic adhesive and its correlation with the degree of conversion on varying light-curing tip distances

INTRODUCTION

The aims of this research were to use high-performance liquid chromatography to assess the bisphenol A (BPA) released from an orthodontic adhesive (Transbond XT; 3M Unitek, Monrovia, Calif) with various light-curing tip distances and to correlate the release to the degree of conversion.

METHODS

One hundred thirty-eight premolar brackets were divided into 3 groups of 40 each for the high-performance liquid chromatography analysis and 3 groups of 6 each for assessing the degree of conversion. Fourier transform infrared spectroscopy was used for this purpose. Each group was studied at light-curing tip distances of 0, 5, and 10 mm. Statistical analyses were performed by using 2-way analysis of variance (ANOVA), post-hoc multiple comparisons Tukey HSD tests, and paired t tests. Pearson correlation was used to assess the correlation between the degree of conversion and BPA release.

RESULTS

BPA release was greater in specimens cured with a greater light-curing tip distance. The degree of conversion decreased with increased light-curing tip distances. A negative correlation was found between BPA release and degree of conversion.

CONCLUSIONS

Clinicians should ensure that the adhesive is completely cured by keeping the light-curing tip as close to the adhesive as clinically possible.

Presence of cariogenic streptococci on various bracket materials detected by polymerase chain reaction

OBJECTIVE

To determine the in vivo presence of Streptococcus mutans and Streptococcus sobrinus on different bracket materials and to correlate the prevalence with the Visible Plaque Index (VPI) and the Gingival Bleeding Index (GBI).

METHODS

Orthodontic brackets made of different materials (stainless steel, gold, ceramic, plastic) were bonded to the upper and lower second premolars in 40 subjects receiving fixed orthodontic appliances. After 30 days, the brackets were debonded and the presence of S. mutans and S. sobrinus on the brackets was determined using the polymerase chain reaction (PCR) technique. The VPI and GBI were recorded and the relationship between the prevalence of the streptococci and the level of oral hygiene was calculated.

RESULTS

There were fewer S. mutans and S. Sobrinus over the surface of gold and stainless steel brackets compared with the plastic and ceramic brackets. A statistically significant difference was observed in S. mutans and S. sobrinus prevalence between the metal brackets and the aesthetic brackets. However, there were no statistically significant differences in S. mutons and S. Sobrinus prevalence when the gold and stainless steel brackets were compared. Comparison between the plastic and ceramic brackets revealed a similar finding. Furthermore, a significant correlation was found between the in vivo prevalence of S. mutans and S.sobrinus and the oral hygiene indices (p < 0.05), suggesting that the oral hygiene indices could be a good indicator of S. mutans and S. sobrinus prevalence.

CONCLUSIONS

Since microbial adhesion is greater on aesthetic brackets, good oral hygiene during treatment should be emphasised.

Evaluation of the accuracy of linear measurements on spiral computed tomography-derived three-dimensional images and its comparison with digital cephalometric radiography

OBJECTIVES

The aim of the study was to evaluate the accuracy of linear measurements obtained from reconstructed spiral CT images of human dry skulls in three planes by comparing them with direct skull measurements, and then to compare these with measurements made on photostimulable phosphor cephalograms.

METHODS

Using a Siemens Somatom Sensation spiral CT scanner (Munich, Germany), CT images of six human dry skulls were imported into imaging software (Mimics 11.02 Materialise, Leuven, Belgium) and the measurements made were compared to the direct measurements made using a digital calliper (500-171, CD-6C, Mitutoyo, Kawasaki, Japan). The measurements were also compared to those made on frontal and lateral cephalograms taken using a digital cephalostat (Planmeca Oy, Helsinki, Finland). The mean of the 15 linear measurements obtained were compared using the paired Student's t-test.

RESULTS

CT measurements did not show a significant difference from the direct skull measurements (P < 0.05) in all three planes except for two midsagittal measurements in the anteroposterior plane. Cephalometric measurements were comparable to direct skull measurements for midsagittal measurements in the anteroposterior plane, but showed a significant difference when bilateral measurements were considered. Cephalometric measurements also showed a significant difference in the transverse plane from direct measurements and CT measurements; however, they did not display a significant difference between direct skull measurements and CT measurements for most parameters in the vertical plane.

CONCLUSION

Linear measurements on the spiral CT were comparable to anatomical measurements and were more reliable than cephalometric measurements. Cephalometric measurements were acceptable for midsagittal measurements in the anteroposterior plane, but showed a significant variation from anatomical and CT measurements in most other parameters.

Cleidocranial dysplasia: a family report

A 10-year-old girl presented with a chief complaint of many unerupted teeth. Complete clinical and radiological examination of this patient confirmed the diagnosis of cleidocranial dysplasia (CCD). Her father also presented similar features with a lesser clinical severity. CCD is an autosomal-dominant heritable skeletal disease caused by heterozygous mutations in the osteoblast-specific transcription factor RUNX2 gene. Failure of tooth eruption is probably mainly due to this mutated gene in CCD patients. Interdisciplinary treatment approach is obligatory for rehabilitation of these patients. In confirmed cases, genetic counseling for family planning should certainly be advised.

The effect of topical fluoride agents on the physical and mechanical properties of NiTi and copper NiTi archwires. An in vivo study

AIM

The aim of this in vivo study was to determine the effect of topical fluoride agents on the mechanical properties of NiTi and copper NiTi archwires.

METHODS

Thirty patients with fixed appliances were randomly divided into three groups: Group I (Control group) used no topical fluoride agents; Group II used a fluoride rinse; Group III applied a fluoride gel to the teeth. After 30 days, the archwires were retrieved and the moduli of elasticity and yield strengths measured. The groups were compared with the oneway ANOVA, and Tukey's HSD test was used to identify the significant groups. One wire was randomly selected from each group and the surface examined with a scanning electron microscope.

RESULTS

During unloading the modulus of elasticity of the NiTi archwire fell significantly in the gel group. The moduli of elasticity and yield strengths of the NiTi archwires during loading, and the copper NiTi archwires during loading and unloading, were not affected by either the gel or the rinse. Scanning electron microscopic analysis revealed that the copper NiTi archwires in the gel group had the most pitting.

CONCLUSIONS

Topical fluoride agents alter the mechanical properties of NiTi wires and, hence, may prolong orthodontic treatment.

Controlled clinical assessment of astemizole in the treatment of chronic idiopathic urticaria and angioedema

Astemizole, one of the newer generation of nonsedating antihistamines, was evaluated in a double-blind study of forty-six patients who had chronic idiopathic urticaria with or without angioedema; most had severe disease. Nineteen of twenty-three patients who were on placebo discontinued treatment because of lack of response compared to only five of twenty-three astemizole-treated patients (p less than 0.0001). Fourteen of twenty-two astemizole-treated patients and two of twenty-two placebo-treated patients considered the results to be good or excellent (p less than 0.0001). Blinded assessment by the investigators yielded similar results (p less than 0.0001). Therapeutic response was the same in patients with and without angioedema in addition to urticaria and in those requiring corticosteroids. Duration of urticaria also did not influence the results. Increased appetite and weight gain were the main side effects reported more frequently in the astemizole-treated than in the placebo-treated group, and no significant toxicity was noted. Follow-up after terminating the drug study indicated a high frequency of remissions during the subsequent year.