Evidence-based orthodontics

doi:10.1179/146531205225020872

HOME

HELP

FEEDBACK

SUBSCRIPTIONS

Article

Evidence-based orthodontics

Jayne E. Harrison

Liverpool University Dental Hospital, UK

Donohue VE, Marshman LAG, Winchester LJ.

Objectives: To compare the maxillary expansion efficacy andrate of expansion brought about by quadhelix appliance (QH)and a nickel titanium palatal expander (NiTi).

Design: A controlled clinical trial with allocation alternatingbetween patients.

Setting: East Grinstead, UK.

Participants: Thirty three consecutive patients in the latemixed or permanent dentition with a unilateral or bilateralcrossbite.

Interventions: Quadhelix: a custom-made appliance made out of0.8mm heat-treated blue Elgiloy^® expanded by one molar’swidth posteriorly. NiTi expander: a pre-formed removable appliancewith two 0.8mm stainless steel palatal arms connected to a 0.9mmNiTi tandem loop that was cooled to facilitate insertion.

Outcome measures: Efficacy (E_max), rate (m_max) and variance(V_E and V_m) of maxillary expansion; discomfort and cost-effectiveness.

Results: Twenty-eight patients (85%) completed maxillary expansion.There were no significant differences between E_max and m_maxor V_Eof either group across the molars or premolars (p=0.16–0.98).There were significant differences between the E_max (p=0.001)and m_max (p=0.0001) with the QH across the molars compared withthe premolars but not the NiTi (p =0.11). V_mfor the NiTi expanderwas significantly greater than the QH across the molars (p=0.004)and premolars (p=0.009). The QH and NiTi expander caused similaramounts of discomfort except on days 6 (p=0.04) and 7 (p=0.03)after the second activation when the NiTi expander was significantlyless uncomfortable. None of the QH group and eleven of the NiTiexpander group required more than one appliance.

Conclusions: The QH and NiTi expander produced similar amountsof maxillary expansion. The QH appeared to produce more consistentexpansion and needed only one appliance to produce the expansionbut was more painful when reactivated.

Implications: This study suggests that the custom-made QH wasas effective at producing maxillary expansion as the pre-formedNiTi expander but the QH produced more consistent expansionand was more cost-effective.

Cacciafesta V, Sfondrini MF, Melson B, Scribante A.

Objectives: To compare the clinical performance of recycledwith new stainless steel brackets.

Design: A split-mouth randomised controlled trial.

Setting: Aahus, Denmark.

Participants: Twenty patients requiring upper and/or lower fixedappliance therapy who were free of caries, hypoplasia, restorationsand occlusal interferences

Interventions: Teeth in contra-lateral quadrant were bondedwith either recycled or new Orthos^# stainless steel brackets.Recycling involved the brackets being washed in non-acid solution,dried and heated to 350°C for 24 hours then rewashed twice,dried and electro-polished for 20 seconds and finally sterilizedat 250°C.

Outcome measures: Bond failure rate and time to bond failure.

Results: Overall, in 12 months there were 9 (5.8%) failuresof the new brackets and 11 (7.1%) of the recycled ones. Thiswas not statistically significantly different (p=0.65). Therewere also no statistically significant differences between thefailure rate of the each bracket type when comparing upper andlower arches (p>0.33) or anterior and posterior teeth (p>0.33). There was no significant difference in terms of bracketfailure risk over 12 months between the two bracket types (hazardratio 0.77 95% CI 0.31–1.93).

Conclusion: The results of this study suggest that the bondfailure rate and survival of the recycled brackets was similarto the new brackets.

Implications: It appears that this recycling method did nothave an impact on bond failure rate or survival over a 12-monthperiod. However, this study did not address other outcomes thatmay have been affected by the recycling process e.g. effectsof slot or base distortion. Recycling may have economic andecological advantages but clinicians need to be aware of theproblems that may occur with recycling and patients informedof the type of bracket they are being treated with.

Araujo AM, Buschang PH, Melo ACM.

Objectives: To describe condylar growth and mandibular remodellingwith bionator therapy.

Design: A randomised controlled trial.

Setting: Unclear.

Participants: Twenty-five patients, with Class II division 1malocclusions, aged 6.9–11.2 years with minimal crowding(<1.5mm) and no crossbites.

Interventions: Both groups: Three mandibular implants were placed;one in the symphysis and one either-side proximal and inferiorto the first permanent molar. Participants were randomly allocatedto either no treatment or bionator treatment and followed-upfor one year.

Outcome measures: Implant displacement, mandibular growth androtation measured cephalometrically.

Results: The bionator group showed statistically significantlymore posterior growth and remodelling at posterior gonion (p=0.018)and condylion (p=0.025) than the control group. There were nostatistically significant differences between the two groupsin the amount of vertical growth occurring (p=0.147–0.701).The total changes were only significantly different at posteriorgonion (p=0.033) with the bionator group experiencing more growth.Significantly more horizontal displacement (p=0.04–0.01)of the all the implants and vertical displacement if the anteriorimplant (p=0.012) occurred in the bionator group. However, significantlyless forward rotation of the mandible (p=0.014) took place inthe bionator group.

Conclusions: This implant study suggests that the bionator inducesgreater amounts of posterior growth and remodelling in the gonialand condylar regions; displaces the mandible forwards but limitsthe amount of forward rotation.

Implications: It appears that anterior posturing of the mandibleencourages remodelling at the angle and condyle that resultsin the mandible being displaced anteriorly, its forward rotationbeing limited, thus helping to reduce the overjet and overbitein Class II division 1 malocclusions.

Elaut J, Wehrbein H.

Objectives: To compare argon laser-curing of a light-activatedresin adhesive (Transbond XT, 3M Unitek, Monrovia, California,USA) with conventional light-curing.

Design: A controlled clinical trial.

Setting: University department and private practice in Belgium.

Participants: Forty-five patients, with a total of 742 teeth,requiring two arch fixed appliance therapy ± extractions.

Interventions: Alternate teeth were cured using either conventionallight-curing for 40 seconds (Curing light XL3000, 3M Unitek,Monrovia, California, USA) or argon laser-curing for 10 seconds(Flexilas Argon laser, ARC Laser GmbH, Eckental, Germany). Thebrackets were placed on the control teeth before the experimentalteeth. Aluminium shielding appliances were used to avoid laserirradiation of the control teeth.

Outcome measures: Bond failure rate, decalcification and plaquescores over 14 months.

Results: Significantly fewer (p=0.038) bond failures occurredin the argon laser-cured group (9/371, 2.4%) than the conventionallight-cured group (21/371, 5.7%). There were no significantdifference in the amount of decalcification occurring or theplaque scores (p >0.05).

Conclusions: This study suggests that argon laser-curing ofan orthodontic resin reduced the bond failure rate and did notaffect the amount of decalcification occurring or plaque scoreswhen compared with conventional light-curing.

Implications: It appears that curing orthodontic resin withan argon laser may have benefits in terms of a reduced bondfailure rate and time. However, there may be added hazards,in terms of potential for retinal damage, when using the laser.

Cacciafesta V, Sfondrini MF, Scribante A.

Objectives: To compare the clinical performance of adhesivepre-coated stainless steel brackets (APC brackets, 3M Unitek,Monrovia, California, USA) cured with either a plasma arc lightor a conventional halogen light.

Design: A split-mouth randomised controlled trial.

Setting: Orthodontic practice, Italy.

Participants: Thirty patients, with a total of 600 teeth, requiringsingle or two-arch fixed appliance therapy non-extraction therapywho had no caries, hypoplasia, fillings or occlusal interferences.

Interventions: APC brackets in contra-lateral quadrants werecured using either a conventional halogen light for 20 secondsor a plasma arc light for 5 seconds.

Outcome measures: Bond failure rate over 12 months.

Results: There was no significant difference between the bondfailure rate of the APC brackets cured with the halogen (12/300,4%) or plasma arc (21/300, 7%) lights (p=0.09). There was alsono significant difference in the bracket failure risk betweenbrackets cured with each of the two lights (hazard ratio 0.56,95% CI 0.29, 1.13).

Conclusions: This study found that the bond failure rate ofthe APC brackets cured with the conventional halogen light waslower that with the plasma arch light but that this differencewas not statistically significant. However, this may be theeffect of the relatively small sample size.

Implications: It appears that curing APC brackets with a plasmaarc light may be as effective as a conventional halogen lightand have benefits in terms of a reduction in time needed tobond-up. However, a larger study, powered to detect the differencefound in this study, is required to verify these findings.

Summers A, Kao E, Gilmore J, Gunel E, Ngan P.

Objectives: To compare the survival rate and mode of failureof orthodontic brackets bonded with a resin modified glass ionomer(RMGI) and a conventional resin adhesive.

Design: A split-mouth randomised controlled trial.

Setting: University department, West Virginia, USA.

Participants: Twenty-two patients, in the permanent dentition,receiving comprehensive orthodontic treatment who had no decalcificationand good oral hygiene.

Interventions: Brackets in contra-lateral quadrants were bondedwith either Fuji Ortho LC RMGI or Light Bond resin adhesive(both from Reliance Orthodontic Products, Itasca, Illinois,USA).

Outcome measures: Bond failure rate and adhesive remnant index(ARI).

Results: The mean observation time was 1.32 years (max 1.82years; min 0.59 years). There were no significant differencesbetween the bond failure rate of the brackets bonded with FugiLC RMGI (13/199, 6.5%) and Light Bond (10/199, 5%) adhesives(p<0.41) or the ARI score for each adhesive (p<0.52).

Conclusions: This study found that the bond failure rate ofthe brackets bonded with the RMGI was higher and the ARI scorelower than those bonded with the conventional resin adhesivebut that these differences were not statistically significant.However, this may be the effect of the relatively small samplesize.

Implications: It appears that the bond failure rate and adhesiveremnant index score of Fuji LC RMGI were similar to a conventionalresin adhesive suggesting that the bond strength of this RMGIwas adequate for clinical use. However, a larger study is requiredto verify these findings.

Benson PE, Douglas CWI, Martin MV.

Design: A split-mouth, cross-over, randomised controlled trial.

Setting: University departments, Liverpool and Sheffield, UK.

Participants: Thirty patients with good oral hygiene who wereabout to receive fixed orthodontic treatment and were not pregnantor diabetic; using an anti-microbial mouthwash or had not takenantibiotics in the last two months.

Interventions: Fluoridated or non-fluoridated elastomeric ligatureswere used to ligate contra-lateral maxillary incisors and theopposite mandibular canine. After six weeks the elastomers wereremoved and the plaque collecting on them sent for laboratoryanalysis. Non-fluoridated ligatures were placed for six weeksas a washout period and then the opposite configuration of elastomerswere placed for a second experimental period.

Outcome measures: Strepococcus count expressed as a percentageof the total aerobic count.

Results: Twenty-seven patients completed the trial. There wereno significant differences in the streptococcal count (p=0.29)or total anaerobic count (p=0.23) between the plaque collectedfrom fluoridated and non-fluoridated ligatures.

Conclusions: This study found that the incorporation of fluorideinto elastomeric ligatures did not reduced the microbial loadof the plaque collecting on them.

Implications: Fluoridated ligatures are not effective at reducingthe streptococcal or anaerobic growth in locally forming dentalplaque.

Oliveria NL, Da Silveira AC, Kusnoto B, Viana G.

Objectives: To evaluate the differences in outcome between theHaas and Hyrax appliances.

Design: A randomised controlled trial.

Setting: Three university departments and one private practice,Chicago, USA.

Participants: Nineteen patients requiring rapid maxillary expansionto correct a uni- or bilateral crossbite.

Interventions: A Haas^# (tissue borne) or Hyrax^* (tooth borne)appliance. Expansion at a rate of 2 quarter turns (0.5mm) perday until adequate over expansion was achieved.

Outcome measures: Skeletal and dental variables measured fromantero-posterior cephalograms. Dental and palatal variablesmeasured from study models by a non-contact surface laser scanner^*#.

Results: The groups were comparable at baseline (p=0.12–0.92).There were significant differences between the appliances inthe intermolar width expansion achieved (p=0.02), total increasein intermolar perimeter (p=0.01) and change in palatal shelfangulation (p=0.01) with the Haas appliance producing more expansionand having less of an effect on the angulation of the palatalshelves than the Hyrax appliance.

Conclusions: It appears that the Haas appliance achieved maxillaryexpansion with more of an orthopaedic effect whereas the Hyraxappliance achieved expansion by dentoalveolar expansion.

Implications: It appears that when orthopaedic expansion ofthe maxilla is required the Haas expander may be the applianceof choice.

Van Steenbergen E, Burstone CJ, Prahl-Anderson B, Aartman IHA.

Objectives: To test the null hypothesis that headgear has noeffect on the steepening, extrusion and narrowing of the buccalsegments or on the rate of incisor intrusion when using an intrusionarch.

Design: A randomised controlled trial.

Setting: Apeldoorn, The Netherlands.

Participants: Twenty patients needing maxillary central andlateral incisor intrusion of at least 2mm.

Interventions: All patients had initial levelling and aligningof the upper incisors and the buccal segments up to 0.018''x0.025''stainless steel archwires. Then an intrusion arch was addedto deliver 40g at the midline. Intervention: High-pull headgear,200g per-side, for eight hours at night. Control: No headgear.

Outcome measures: The vertical movement of the central incisors(intrusion) and buccal segments and change in axial inclinationof the buccal segment measured from cephalograms. Change ininter-molar width measured from study models. The rate of incisorintrusion (mm/ week) was calculated.

Results: There were no significant differences between the headgearand no headgear group in terms of the amount of intrusion achieved(p=0.71); change in axial inclination of the buccal segments(p=0.36); vertical movement of the buccal segments (p=0.32)or rate of intrusion. There was significantly more molar expansionin the headgear group (p=0.025).

Conclusions: The high-pull headgear had no effect on the amountof intrusion achieved or the steepening and extrusion of thebuccal segments. However, it did counteract the moment thattends to reduce arch width.

Implications: This study suggests that high-pull headgear isnot as effective at counteracting the vertical side effectsof the intrusion arch as expected but that it did counteractthe lateral side effects. The addition of high-pull headgearwhen using an intrusion arch may therefore not be worthwhileas a transpalatal arch could be used to control the lateraldimension.

The Angle Orthodontist 2004; 74:581–586.

Top
European Journal of Orthodontics...
European Journal of Orthodontics...
European Journal of Orthodontics...
European Journal of Orthodontics...
American Journal of Orthodontics...
American Journal of Orthodontics...
American Journal of Orthodontics...
American Journal of Orthodontics...
The Angle Orthodontist 2004;...
The Angle Orthodontist 2004;...

Two interceptive approaches to palatally displaced canines:A prospective longitudinal study.

Leonardi M, Armi P, Franchi L, Baccetti T.

Objectives: To compare the effectiveness of extraction of thedeciduous canine (DC), with or without the addition of headgear,in patients with palatally displaced canines (PDC).

Design: A randomised controlled trial.

Setting: University Departments in Catania and Florence, Italy.

Participants: Fifty patients with uni- or bilateral palatallydisplaced canines

Interventions: Extraction of the deciduous canine correspondingto the PDC with or without the addition of cervical headgearafter the extraction or observation only.

Outcome measures: Eruption of the PDC within 48 months of theextraction of the deciduous canine.

Results: There was no significant difference in the prevalenceof successful cases between the extraction only group and thecontrol group (p=0.15). The prevalence of successful cases inthe extraction and headgear group was significantly greaterthan the extraction only group (p<0.05) and the control group(p<0.00). No significant difference was found between theintervention groups with respect to the time taken for the canineto erupt in the successful cases (p =0.55).

Conclusions: The extraction of the deciduous canine alone isnot effective at increasing the rate of eruption of PDCs. However,the addition of cervical headgear, following the extractionof the deciduous canine, did increase the rate of eruption ofPDCs but it did not effect the time taken for them to erupt.

Implications: This study suggests that the extraction of thedeciduous canine alone is not enough to increase the rate oferuption of PDCs and that cervical headgear should be fittedfollowing the extraction in order to increase the effectivenessof this interceptive treatment.

Notes

^# Orthos, SDS/Ormco, Glendora, CA, USA.

^# Haas expanders: Summit Orthodontics, Munroe Falls, Ohio; USA.

^* Hyrax expanders: Great Lakes Laboratories, Tonawanda, New York,USA.

^*# Vivid700: Minolta, Ramsey, New Jersey, USA.

This Article

Full Text (PDF)

Alert me when this article is cited

Alert me if a correction is posted

Services

Email this article to a friend

Similar articles in this journal

Alert me to new issues of the journal

Download to citation manager

Citing Articles

Citing Articles via Google Scholar

Google Scholar

Articles by Harrison, J. E.

Search for Related Content

PubMed

Articles by Harrison, J. E.