Extraction Of Second Premolars Research Articles

Alveolar ridge preservation of two-wall bone defects using mineralized dentin matrix: An experimental pre-clinical study.

To study bone healing of two-wall bone defects after alveolar ridge preservation using mineralized dentin matrix. After distal roots extraction of second and fourth premolars (P2, P4) on one lateral mandible in 12 beagles, two-wall bone defects (5 × 5 × 5 mm) were surgically created distally to the remaining mesial roots of P2 and P4. A total of 24 sites were randomly allocated to three groups (implant material- time of execution): mineralized dentin matrix (MDM)-3 m (MDM + collagen membrane; 3 months), MDM-6 m (MDM particles + collagen membrane; 6 months), and C-6 m (collagen membrane only; 6 months). Clinical, radiographic, digital, and histological examinations were performed 3 and 6 months after surgery. The bone healing in MDM groups were better compared to Control group (volume of bone regenerated in total: 25.12 mm3 vs. 13.30 mm3, p = .046; trabecular volume/total volume: 58.84% vs. 39.18%, p = .001; new bone formation rate: 44.13% vs. 31.88%, p = .047). Vertically, the radiological bone level of bone defect in MDM-6 m group was higher than that in C-6 m group (vertical height of bone defect: 1.55 mm vs. 2.74 mm, p = .018). Horizontally, no significant differences in buccolingual bone width were found between MDM and C groups at any time or at any level below the alveolar ridge. The percentages of remaining MDM were <1% in both MDM-3 m and MDM-6 m groups. MDM improved bone healing of two-wall bone defects and might be considered as a socket fill material used following tooth extraction.

Influence of second premolar extractions on the volume of the oral cavity proper: a control comparative cone-beam computed tomography volumetric analysis study.

To compare the pre- and postorthodontic treatment volumetric changes of the oral cavity proper (OCP) in extraction and nonextraction patients and to identify influencing variables. Pre- and posttreatment cone-beam computed tomography (CBCT) scans of patients undergoing orthodontic treatment with fixed labial appliances and who satisfied the inclusion criteria were individually landmarked. Linear, angular, and volumetric measurements were determined. Descriptive statistics, repeated measure analyses of variance, correlations, and stepwise regression statistical analyses were applied. The CBCT scans of 54 patients who underwent the extraction of second premolars and/or extraction of second primary molars associated with agenic second premolars, and 59 nonextraction patients matched for crowding, were assessed. The mean age for both groups was 15 years. There was a statistically significant increase in the volume of the OCP for both the extraction and nonextraction groups, with the nonextraction group demonstrating a larger increase in the volume of the OCP. Gender, age, changes in mandibular and maxillary arch length, and changes in mandibular and maxillary intermolar width all influenced the change in the OCP volume. The volume of the OCP increased in growing patients with and without the extraction of the second premolars and/or extraction of second primary molars associated with agenic second premolars. Patients who did not have extractions as part of their orthodontic treatment demonstrated a greater overall increase in OCP volume.

Comparative treatment outcomes after bilateral extractions of maxillary second molars or first premolars in patients with class II malocclusion: a retrospective study

BackgroundThis retrospective cohort study aimed to compare treatment results between bilateral extraction of upper second molars (M2) and first premolars (P1) in terms of treatment timing, cephalometry, upper third molar alignment and relapse in the long-term.MethodsFifty-three consecutively treated Caucasian patients with a brachyfacial pattern, skeletal class I and dental class II requiring extraction in the maxilla due to crowding were retrospectively divided into group I (M2 extracted; N = 31) and II (P1 extracted; N = 22). Fixed appliances were inserted after extraction and after distalisation of the first molars in group I. Post-treatment lateral cephalograms were digitally analysed and compared between groups. Six to seven years later relapse and success of upper third molar alignment were clinically evaluated as well as orthodontic treatment duration, pre-treatment age and gender recorded.ResultsAfter debonding patients with second molar extraction showed significantly smaller values for the Wits-appraisal, but higher values for index and facial axis. Extracting first premolars caused significantly more retroinclination/−position of anterior teeth and an increased profile concavity, more relapse and less successful alignment of upper third molars. Orthodontic treatment duration, pre-treatment age and gender were not significantly different between groups.ConclusionsBilateral extraction of upper first premolars or second molars may solve dental crowding in skeletal class I dental class II patients with a brachyfacial growth pattern. Upper second molar extraction seems to affect maxillary third molar alignment, long-term stability and dental and soft-tissue cephalometric parameters positively, but no intervention proved to be clearly superior.

The effect of maxillary first and mandibular second premolar extractions on the posterior Bolton ratio

The anterior and overall Bolton ratios and their application in orthodontics are widely known. However, little has been reported about the posterior Bolton ratio, how it is affected by the extraction of posterior teeth, and its application in orthodontic treatment planning. This study aimed to investigate how extracting maxillary first and mandibular second premolars affects the posterior Bolton ratio. The sample included 55 patients with Class I occlusion within 1 standard deviation of ideal anterior and overall Bolton ratios. The digitized models were subjected to virtual extraction of maxillary first premolars and mandibular second premolars and setup of posterior teeth in ideal occlusion. If space closure compromised occlusion, the teeth were moved to achieve ideal cusp-fossa or cusp-marginal ridge occlusion. The ideal setups were measured for residual interproximal spacing. Statistical analysis used R statistical software (version 2018; R Core Team, Vienna, Austria). The ideal nonextraction posterior Bolton ratio was determined from the sample to be 105.77 ± 1.99%. The ideal expected posterior Bolton ratio for maxillary first and mandibular second premolar extraction patients was 106.52 ± 2.52%. This significantly differed from the expected posterior Bolton ratio for the 4 first premolar extractions. Patients finished with an average of 1.28 mm net residual spacing between mandibular first premolars and first molars; 38.2% of patients finished with at least 1.5 mm of residual space, and 9.1% of patients finished with at least 2 mm of residual space. A patient with ideal anterior, posterior, and overall Bolton ratios treated with maxillary first and mandibular second premolar extractions to ideal occlusion will likely finish with some spacing in the mandibular dentition.

"Zirconia Straight Wire Appliance Combined with Flat Bite Plate for the Treatment of Lingual Tipping Deep Overbite with Undersized Lateral Incisors"

Patient Jiang, Female,25 years old, came to the clinic for irregular teeth. The case was reported as lingual tipping deep overbite with maxillary undersized lateral incisors, which the patient did not accept to restore the malocclusion morphology by denture, resulting in the selection of extraction of bilateral maxillary lateral incisors and mandibular second premolars, and orthodontic treatment by zirconia straight wire appliances combined with flat bite plate.

Treatment Effects and Lip Profile Changes Following Surgical Mandibular Advancement Versus Premolar Extractions in Class II Div 1 Malocclusion: A Randomized Controlled Trial.

No randomized controlled trial has compared the treatment outcome between surgical mandibular advancement and premolar extractions in class II malocclusion. This 2-arm parallel randomized controlled trial evaluated the treatment effects and lip profile changes in skeletal class II adult patients subjected to bilateral sagittal split ramus osteotomy for mandibular advancement and those treated with premolar extractions. Seventy skeletal class II patients were accessed and forty-six subjects who fulfilled inclusion criteria were distributed randomly into Group CG (patients: 23, mean age: 21.28 ± 2.69 years) and Group SG (patients: 23, mean age: 21.15 ± 2.64 years). Group CG was subjected to extraction of maxillary first premolars and mandibular second premolars followed by implant supported space closure and Group SG was managed by surgical mandibular advancement. Skeletal, dental, and soft-tissue changes were analyzed. The study was single-blinded (statistical analyzer). Groups were closely matched for baseline parameters. In the present trial there was no loss to follow-up. Though overjet and overbite were optimized in both the groups but significant improvement was seen in surgical cases. Group CG demonstrated statistically significant point "A" remodeling, dentoalveolar changes, and increase in nasolabial angle. Group SG exhibited significant sagittal and vertical skeletal improvement and lip position change. Surgical mandibular advancement was found to be a better treatment modality compared to premolars extraction for managing skeletal class II div 1 malocclusion as it permits greater improvement of the profile and skeletal relationship.

Efficacy of Transdermal Diclofenac Patch and Ketoprofen Patch as Postoperative Analgesia after Extraction of First Premolars Bilaterally in Both Arches for Orthodontic Purpose: A Comparative Study.

Aim:The aim of the study was to compare the efficacy of transdermal diclofenac patch with ketoprofen patch as postoperative analgesia after extraction of first premolars bilaterally in both arches for orthodontic purpose.Materials and Methods:A split-mouth technique was used in 52 patients with the age group of 15–25 years for extracting maxillary and mandibular first premolars bilaterally for orthodontic reason. A single ketoprofen patch was used after the extraction of premolars from first and fourth quadrant, whereas for the extraction of second and third quadrant premolars, diclofenac patch was used. All the extractions were performed under local anesthesia. The data were compiled and statistically analyzed using the student's t-test.Results:Mean visual analog scale score for diclofenac and ketoprofen patch was 2.05 (0.75) and 1.09 (0.3), respectively. Thirteen patients required additional medication (25%) and 1 (1.9%) patient with diclofenac and ketoprofen patch, respectively. No major complication or adverse effects were observed in any of the groups.Conclusion:Both diclofenac and ketoprofen transdermal patches are helpful in relieving pain after orthodontic extraction. Patients with diclofenac patch required more additional analgesia within 24 h compared to that with ketoprofen patch. None of the drugs showed any significant adverse effects and were well tolerated by the patients.

Treatment of Class II malocclusion with the improved superelastic nickel-titanium alloy wire and long hooks for mandibular molar protraction

• Two patients were treated with extraction of the mandibular second premolars. • We used superelastic nickel-titanium alloy wires as working wires. • The use of nickel-titanium wires and long hooks worked to mesialize the molar bodily. The mandibular first molar must be carefully moved to prevent mesial tipping and extrusion in case extraction of the mandibular second premolar is required to achieve the desired goals. The nickel-titanium alloy has unique mechanical properties, including superelasticity and shape memory, leading to the generation of continuous light forces that may be more biologically compatible than intermittent strong forces. However, it provides poor root control because of its low stiffness. We herein have experienced the patients with Angle Class II malocclusion that uses the improved superelastic nickel-titanium wire (ISW) and long hooks to achieve bodily movement of the mandibular first molar. The 0.022 × 0.028-in slot preadjusted edgewise appliances and 0.020 × 0.025-in ISWs as the working archwire were used. We pinched the crimpable long hooks on the rectangular ISW and applied 100-150 g of contractile force between the fixed long hooks and bracket hooks of the mandibular first molars to activate the system with ligature wire lacing. The mandibular molars were uprighted and mesially moved; panoramic radiographs did not indicate severe root resorption. These experiences suggest that this method involving the combined use of the ISW and long hooks may be one of the useful methods for closing spaces by facilitating the uprighting and mesial movement of the molars in treating Class II malocclusion.

Keys to Class II correction: A comparison of 2 extraction protocols

The purpose of this study was to evaluate the effects of 2 extraction patterns on incisor and molar movements in patients with growing Class II Division1. The sample included 54 patients 10-17years of age treated by 2 private practice orthodontists using Tweed directional force mechanics, 4 premolar extractions, J-hook headgears, and Class II elastics or Saif springs. The sample was divided on the basis of having maxillary and mandibular first premolars (4/4) or maxillary first and mandibular second premolars (4/5) extracted. Each group included 27 patients. Treatment lasted 2.8±0.60years and 2.6±0.54years for the 4/4 and 4/5 groups, respectively. Pretreatment (T1) and posttreatment lateral cephalograms and dental casts were evaluated. Cranial base, mandibular, and maxillary superimpositions were performed to quantify tooth movements and displacements. There were no statistically significant T1 between-group differences in crowding or in the SNA, SNB, ANB, and MPA angles. Analyses of covariance, controlling for statistically significant (P<0.05) differences in T1 mandibular incisor position, showed that mandibular first premolars extractions produced greater (1.6mm) mandibular incisor retraction than second premolar extractions. The mandibular first molars were protracted significantly more (0.7mm) after the second premolar than the first premolar extractions. Within-group changes of the MPA, between-group differences in the changes in MPA, and the amount of vertical eruption of the maxillary and mandibular molars were not significantly different between the 2 extraction patterns. Extraction of mandibular second premolars enhances Class II molar correction, with greater mesial first molar movement and less distal incisor movement. Neither extraction pattern has an effect on the MPA or the vertical dimension (ie, there was no "wedge effect").

Treatment of a Class I Malocclusion with Severe Crowding using Passive Self-Ligating Brackets Passive Self-Ligating Brackets

Presently, dental crowding is the most common problem among orthodontic patients. The prevalence of crowding in the dental arch is significantly increased in modern dentitions, and it is the most common reason why patients pursue orthodontic treatment. Objective: To report an advanced bracket systems, namely self-ligating brackets, to increase the efficacy of orthodontic treatment especially in patients with severe crowding. Case Report: A 22-year-old female patient presented with severe crowding of the maxillary and mandibular arches. In the upper arch, both second premolars were palatally positioned; in the lower arch, the lower right canine was lingually positioned and the lower left second premolar was extracted. The patient had a balanced facial profile with a straight profile and skeletal Class I relationship. Treatment was initiated using passive self-ligating brackets followed by extraction of the upper second premolars and the lower right first premolar. Conclusion: The use of passive selfligating brackets proved to be effective and resulted in a significant improvement in the patient’s dental and smile esthetics. The active treatment time was 11 months; this resulted in successfully alleviating the crowding of the maxillary and mandibular arches and significant improvement in the occlusal relationship.

Dental and soft tissue changes following extraction of second premolars in females with bimaxillary protrusion: A retrospective study.

Bimaxillary protrusion is a condition wherein esthetic concerns are the main reason behind seeking orthodontic treatment. The aim of this retrospective cephalometric study was to evaluate the soft tissue profile and dental changes among female Saudi bimaxillary protrusion patients treated with extraction of all second premolars followed by retraction of the anterior teeth. Subjects and Methods: Pre and posttreatment cephalometric radiographs of adult female patients (ages 18-30 years) who underwent orthodontic therapy for Class I bimaxillary protrusion were obtained. Data were analyzed with SPSS® software. A paired t-test and Pearson's correlation coefficients were conducted with the statistical significance set at 95% (P value < 0.05). At posttreatment, there was an overall decrease in the mean values among the majority of the soft tissue and dental cephalometric angles and linear measurements. Among soft tissue variables, there was a marginal increase in the upper lip length by 1.49 mm (P < 0.001), and the nasolabial angle increased markedly by 7.64° (P < 0.001). Similarly, a marked increase in retroclination by 5.95° (P < 0.001) was observed among the dental variables. Conversely, no significant changes were noted in the lower incisors. Pearson's correlation analysis revealed a significant correlation between all the different dental variables. Within the soft tissue variables, there was a significant positive correlation between changes in the upper lip protrusion, lower lip protrusion, upper lip thickness, and the distance from the upper and lower lips to the S-line.

Mandibular dental changes following serial and late extraction of mandibular second premolars.

To determine changes in occlusal curves and dental tipping occurring from mandibular second premolar serial extraction, early extraction of deciduous mandibular second molars with missing second premolars, and late second premolar extraction compared with untreated controls. Information was collected from 85 subjects at three time points: T0, prior to serial extraction; T1, after serial extraction and drift prior to orthodontic treatment, and pretreatment for the late premolar extraction patients; and T2, posttreatment. Untreated age- and gender-matched controls were used for comparison. Three occlusal curves were measured on digitized mandibular casts, and dental tipping was assessed using lateral cephalograms. At T0, there were no significant differences among groups. At T1, there was significant steepening of Monson's sphere and the curve of Wilson between early and late extraction and control groups. At T2, the differences in Monson's sphere and the curve of Wilson were fully corrected. At T1, there were significant differences in the tipping of mandibular 6's, 4's, and 3's between the early extraction groups compared with the late extraction and control groups. At T2, these differences in tipping were fully corrected. There were no differences in mandibular incisor tipping between groups at T1 or T2. Serial extraction produced steeper occlusal curves and significant tipping of mandibular first molars, first premolars, and canines after extraction and physiologic drift (T1). Accentuated occlusal curves and tooth tipping were fully corrected following orthodontic treatment (T2). Mandibular incisor position was unchanged by serial or late second premolar extraction.

Cephalometric Assessment of Changes in Vertical Facial Height Following Extraction of Mandibular Second Premolars in Adult Long-face Patients with Skeletal Open Bite: A Case Series

Cephalometric Assessment of Changes in Vertical Facial Height Following Extraction of Mandibular Second Premolars in Adult Long-face Patients with Skeletal Open Bite: A Case Series

Tooth extractions in Orthodontics: first or second premolars?

ABSTRACTTooth crowding and protrusions demand rigorous attention during orthodontic planning that includes the extraction of first and second premolars. Some characteristics, such as dentoalveolar bone discrepancies, maxillomandibular relations, facial profile, skeletal maturation, dental asymmetries and patient cooperation, are important elements of an orthodontic diagnosis. This study discusses the options of treatments with extractions and describes the correction of a Class I malocclusion, bimaxillary protrusion, severe anterior crowding in both dental arches and tooth-size discrepancy, using first premolar extractions.

Treatment of a patient with mandibular deviation and dentofacial various problems on alignment and multidirectional relationships

A 22-year-old female with a mandibular rightward deviation, facial asymmetry, lower dental midline rightward deviation, anterior open bite, anterior crossbite, posterior crossbite, Class III molar relationship, and severe crowding had surgical orthodontic treatment. Following extraction of the upper second premolars, lower right first premolar, left second premolar, and all four third molars, the upper and lower teeth were aligned and dental arch widths coordinated in the preoperative orthodontic treatment. The mandible was moved backward and rotated to the left with a bilateral sagittal split ramus osteotomy. Acceptable facial esthetics and occlusion were obtained. The improvements in facial appearance and the dental arches remained stable after 2 years and 11 months.

A retrospective study comparing the loss of anchorage following the extraction of maxillary first or second premolars during orthodontic treatment with fixed appliances in adolescent patients.

This retrospective study assessed the difference in anchorage loss using 3D superimposition of study models between cases treated with extraction of maxillary first premolars and maxillary second premolars carried out in orthodontic specialist practice. Sixty subjects who have undergone extractions of either maxillary first or second premolars as part of their orthodontic treatment were selected. Eligibility criteria included patients with a Class I, mild Class II or III malocclusions, mild-to-moderate crowding with no anchorage reinforcement. Pre- and post-treatment maxillary dental study cases were scanned using a surface laser scanner to produced 3D digital images which were superimposed using areas of stability on the anterior hard palate. Anchorage loss was measured by the mesial movement of the maxillary first permanent molar. The mean mesial movement for the maxillary first molars, when adjusted for confounding factors was 4.7 mm (SD 1.6) in the maxillary first premolar extraction group and 4.6 mm (SD 1.6) in the maxillary second premolar extraction group. There is no difference in anchorage loss when comparing the extraction of the maxillary first premolars to the extraction maxillary second premolars.

The effect of first and second premolar extractions on third molars: A retrospective longitudinal study

ObjectivesTo analyse the effect of first and second premolar extractions on eruption space for upper and lower third molars and on third molar position and angulation during orthodontic treatment. MethodsThe sample consisted of 296 patients of which 218 patients were orthodontically treated without extraction and 78 patients with extraction of first or second premolars. The eruption space for third molars was measured on pre– and posttreatment lateral cephalograms, whereas the angulation, vertical position, the relation with the mandibular canal and the mineralization status of third molars were evaluated using pre– and posttreatment panoramic radiographs. All data were statistically analyzed. ResultsThe increase in eruption space and the change in vertical position of upper and lower third molars significantly differed between patients treated with and without premolar extractions, whereas the change in angulation, relationship with the mandibular canal and mineralization status of the third molars did not significantly differ between patients treated with and without premolar extractions. ConclusionsThe retromolar space and the position of third molars significantly change during orthodontic treatment in growing patients. Premolar extractions have a positive influence on the eruption space and vertical position of third molars, whereas they do not influence the angular changes of third molars. Due to the retrospective character of the study, these conclusions should be carefully considered. Further prospective research is necessary for better insights into this complex topic. Clinical significanceThis study stresses the importance of considering the possible effects of orthodontic treatment on third molars during treatment planning.

Incidence of Risk and Complications Associated with Orthodontic Therapeutic Extraction.

Background:Extraction in orthodontics are carried out in the cases where there is space deficiency to align the teeth. The elective extraction of first or second premolars has been discussed in the literature for more than 50 years. In the 1940s and 1950s Nance, Dewel and Carey reviewed this as a useful option, and in the 1970s Logan and other leading orthodontists favoured the extraction as choice. It is not always the elective extraction of premolar is a smooth drive for the surgeon as well as to patient. Sometimes the elective extraction of premolar result in complications, which might be due to both anatomical and surgical factors.Methodology:The study sample consisted of 100 patients referred for one or more orthodontic extractions to the department of oral and maxillofacial surgery were included in this retrospective study at the vivekanandha dental college for women tiruchengode between November 2014 and May 2016. All referrals were from the department of orthodontics. A survey was carried out to record the intraoperative risks and correlated with its morbidity as when occured. All intraoperative morbities were managed appropriately as required.Result and Conclusion:Between November 2014 and May 2016, 100 patients had one or more premolar teeth removed by the oral surgeons. The sample size was 100 patients who had a total of 334 premolars removed. The sample's mean age was 11.4+\\- 8.4 years, and 57.0% were male. The average number of teeth extracted per patient was 2.34 +\\- 1.46, and 73.8% had complete root development. More than 93.4% of subjects had normal root and bone morphology, whereas 35.65% had variations in root forms and bone texture. The intra-operative and post operative complication rates were 7.4% and 1.9%, respectively. Complications were generally minor (91.9%) and were managed nonoperatively on an outpatient basis. There were no case of oral antral communication.

Study on bone regeneration with two different ratios of nano-hydroxyapatite and collagen grafts after tooth extraction in dogs

To compare the effect of bone regeneration with two different ratios of nano-hydroxyapatite(nHA)/collagen(Col) (nHAC) after tooth extraction in canine. Two kinds of nHAC grafts were prepared with different nHA/collagen ratio of 3∶7 and 5∶5. Eighteen male healthy adult dogs had been randomly divided into three groups. Immediately after extraction of the mandibular second premolars, each kind of nHAC was implanted into extraction sockets as follow: Group A, nHA/Col=3∶7(12 sites); Group B, nHA/Col=5∶5(12 sites); Group C, blank control group(12 sites). The bone repairing abilities of the two grafts such as vertical distance of alveolar, CT values, general observation, histological observation, trabecular volume fraction and porosity were separately analyzed at 1st, 3rd and 6th month, respectively (each group had 4 sites in different time periods). nHAC were absorbed gradually after they were implanted into alveolar bone defect and were replaced by new bone. The vertical distance of alveolar bone in Group A([15.76±0.28] mm) was significant higher than that in Group B([14.88±0.36] mm), and CT values of Group A([879±31] HU) were higher than those in Group B([718±29] HU) (P<0.05). The trabecular bone volume percentage of Group A([22.2±0.4]%) was higher than that in Group B([20.3±0.4]%), and the bone porosity of Group A([23.6±0.9]%) was lower than that in Group B([27.6±0.6]%) (P<0.05). In addition, the vertical distance, CT values and the trabecular bone volume percentage of Group C was lower than those in Group A and B, but the bone porosity of Group C was higher. The nHAC with nHA/collagen ratio of 3∶7 could better promote bone regeneration than nHAC with the nHA/collagen ratio of 5∶5 did.

Comparison of bone regeneration in alveolar bone of dogs on mineralized collagen grafts with two composition ratios of nano-hydroxyapatite and collagen

To study the effect of two composition ratios of nano-hydroxyapatite and collagen (NHAC) composites on repairing alveolar bone defect of dogs. Eighteen healthy adult dogs were randomly divided into three groups. Two kinds of the NHAC composites were prepared according to the constituent ratios of 3:7 and 5:5; immediately after extraction of the mandibular second premolars, each kind of the NHAC composite was implanted into extraction socket, respectively: Group I, nHA/Col = 3:7; Group II, nHA/Col = 5:5 and Group III, blank control group. The bone-repairing ability of the two grafts was separately analyzed by morphometric measurement, X-ray tomography examination and biomechanical analysis at 1st, 3rd and 6th month post-surgical, respectively.The NHAC composites were absorbed gradually after implanting into alveolar bone defect and were replaced by new bone. The ratios of new bone formation of Group I was significantly higher than that of Group II after 3 months (P < 0.05). The structure and bioactive performance can be improved when the ratio between the collagen and the hydroxyapatite was reasonable, and the repairing ability and effect in extraction sockets are obviously better.