Efficacy of the Miniscrew-Assisted Rapid Palatal Expansion: An Original Research.

Introduction: One of the most common procedures done in orthodontics is the rapid maxillary expansion for the treatment of transverse maxillary deficiency. Hence, in the present study, we aim to evaluate the efficacy of the rapid palatal expansion assisted with the miniscrews. Materials and
Methods: We piloted a prospective observational study among 50 age-matched adolescent participants. They were grouped equally to receive miniscrew and tooth-borne expanders. The alterations after 6 months of wearing the expanders were calculated for the root length variations of the premolars, tipping of the tooth, buccal bone thickness, and the transverse skeletal widths using the "cone-beam computed tomography" images. Comparison of the values was done between the groups using the Chi-square and ANOVA test, deliberating P < 0.05 as significant.
Results: We observed significantly greater values for the miniscrew expander for all the four parameters than the tooth-borne device. However, there was no significant variation for the root lengths variations between the two groups. No tipping was noted for the miniscrew expander. Conclusions: The miniscrew palatal expander brought faster expansion of the palate than the conventional palatal expanders. The miniscrews were also safe with no adverse effects and were efficus. Copyright:

INTRODUCTION

The transverse deficiency of the maxilla and its treatment is one of the most common procedures done by the orthodontists. The expansion of the maxilla is difficult with age, as the sutures fuse more strongly and are more difficult to mobilize.[1] In such cases, the tooth-borne palatal expanders are not sufficient to move the palate transversely. The recently introduced miniscrew expanders are used in such special conditions.[234]

The disadvantage of the tooth-borne appliance for the maxillary expansion such as the buccal and marginal bone loss, tipping, and loss of the anchorage is avoided in the miniscrew expander that is bone borne.[56] Although there are previous studies done to evaluate the miniscrew palatal expansions, there is a deficit of data regarding the application of the miniscrew expanders among the adolescent patients in a prospective study. Hence, in our study, we aim to evaluate the efficacy of miniscrew expanders for the palatal expansion.

MATERIALS AND METHODS

We piloted a prospective clinical study among 50 age-matched adolescent participants of both the genders. The study was conducted for 2 years. They were grouped equally and were given conventional tooth borne – “hyrax” appliance and miniscrew expanders. The ethics approval was obtained for the study. The patient and the guardians' consent were taken after the study design was explained to them. We included the participants with the transverse maxillary deficit and with no other medical conditions that might alter the outcome of our study.

The parameters measured were root length variations of the premolars, tipping of the tooth, buccal bone thickness, and the transverse skeletal widths that were calculated using the cone-beam computed tomography images, that were taken at the start of the treatment and at the end of 6 months, the primary outcome being the correction of the crossbite. Following the guidelines, the appliances were placed and were activated two turns per day. The values obtained were compared using the IBM SPSS Statistics for Windows, version XX (IBM Corp., Armonk, N.Y., USA Version 20), applying the Chi-square and ANOVA test deliberating P < 0.05 as significant.

RESULTS

We observed a significantly greater expansion in the incisive foramen, nasal cavity, sutural widths, and total skeletal expansion for the miniscrew than the conventional expanders. Lower buccal bone width was seen in the conventional expander than the miniscrew and the variation was significant. There was significantly lower tipping in the miniscrew group than in the conventional. The root length variation was not significantly different between both the groups. There was no significant variation between the groups for the stability of the bone expansions [Table 1].

Table 1

Comparison of the two expanders for the various parameters at the different timelines

Parameter	Type of expander	Pretreatment	At the end of 6 months	P
Maxillary expansion	Tooth borne	21±5.3	27±8.2	0.000
	Miniscrew	23±1.2	28±5.8
Nasal suture width	Tooth borne	12±3.2	15±7.1	0.000
	Miniscrew	13±1.5	16±9.1
Incisive foramen width	Tooth borne	3.3±9.1	6.1±0.2	0.000
	Miniscrew	3.2±5.1	4.9±2.8
Tipping	Tooth borne	92.1±5.3	87.6±6.0	0.000
	Miniscrew	91.0±4.2	91.0±4.1
Root length variation	Tooth borne	20.1±1.2	20.7±1.2	NS
	Miniscrew	20.1±2.3	20.1±1.7
Buccal thickness width	Tooth borne	0.9±1.5	0.6±8.4	0.000
	Miniscrew	0.9±2.9	0.8±4.6

NS: Not significant

DISCUSSION

In our study, the findings suggest that among the adolescents, the rapid maxillary expansion occurred for both the appliances; however, greater values were seen for the miniscrew appliance than the conventional. Similar to the previous observations, the conventional expander opened the suture at the incisive foramen in the form of a wedge while the new miniscrew expander opened the sutures more uniformly and parallel.[5678] The findings that were seen in our study for the tipping of the teeth and the buccal bone resorption are similar to the studies of Hansen et al.[2] and Tausche et al.[3] These differences may be explained by the fact that the tooth-borne appliance exert forces on the tooth and the periodontium of the supporting teeth hence the resorption and the tipping. The bone-borne appliance took the support of bone rather than the tooth, and hence very little tipping or buccal bone resorption was noted.[678] Contrary to previous studies in our study, no root resorption was seen for both the appliances.[78]

There were few limitations in our study, such as the effect of the gender was not considered. Blinding of the investigators was not done in our study.

CONCLUSIONS

Within the limitations of the study, we can conclude that the miniscrew palatal expander was efficus, offers a greater expansion with the least number of side effects than the conventional appliance. Further studies with larger samples and age groups are suggested to corroborate our findings.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.