Effects on the periodontium of vertical bone cutting for segmental osteotomy

What are the surgical risks and 2-year stability of mandibular anterior subapical osteotomy in the treatment of dentoalveolar protrusion?

OBJECTIVE

To investigate the stability and complications of mandibular anterior subapical osteotomy (ASO) in the treatment of bimaxillary dentoalveolar protrusion by way of a retrospective study.

MATERIALS AND METHODS

One hundred and twenty patients who received orthognathic surgery at a single center between 2008 and 2017 were included. Relapse was assessed by serial tracings of lateral cephalograms which were obtained pre-operatively (T1), within 6 weeks after surgery (T2) and at 2 years after surgery. The changes between T2 and T3 represented stability and were tested using the paired t test. The relationship between the extents of surgical repositioning (T2-T1) and relapse (T3-T2) was investigated using the Pearson correlation coefficient. The associations between the variables and the occurrence of relapse and complications identified the risk factors and were evaluated using the χ² test or Fisher's exact test. When r > 0.80, clinical correlation was considered significant; and statistical significance was set at P < 0.05, while confidence interval was set at 95%.

RESULTS

There was a mean uprighting of L1-MP by 12.7°. At 2 years after surgery, 96.7% of the patients experienced a mean relapse of L1-MP by 2.9°. The extent of surgical repositioning was only weakly correlated with that of relapse and no specific factor that increased the risk of relapse could be identified. The most frequent complications were blood loss requiring transfusion, wound dehiscence or infection, gingival recession, and periodontal bone loss, involving 25.8 to 43.3% of the patients. The remaining complications included tooth root damage, fixation hardware exposure or infection, lingual mucosal laceration, and tooth devitalization. There were no cases of avascular necrosis or nonunion.

CONCLUSIONS

Although relapse occurred in most of the patients after 2 years, the actual extent was small (2.9°) which was not likely to be clinically significant.

TRIAL REGISTRATION

HKUCTR-2964 CLINICAL RELEVANCE: Although ASO may be valuable in correcting mandibular dentoalveolar protrusion, the procedure brings with it risks and complications and should be reserved for severe deformities.

Impact of orthognathic surgery on the prevalence of dehiscence in Class II and Class III surgical-orthodontic patients

OBJECTIVES

The objectives were to evaluate and compare the presence of bone dehiscence before and after orthognathic surgery.

MATERIALS AND METHODS

In this retrospective study, 90 cone-beam computed tomography (CBCT) scans from 45 patients were evaluated. Class II (n = 23) and Class III (n = 22) orthodontic patients who were being prepared for orthognathic surgery were measured. CBCT scans were obtained about 30 days prior to (T0) and 6 months after (T1) double jaw orthognathic surgery. The distance between the cemento-enamel junction (CEJ) and the alveolar bone crest was assessed at the buccal and lingual surfaces of all teeth, on both sides and arches, except for the second premolars and the second and third molars. A total of 1332 sites were measured for Class II (644) and Class III (688) patients. The software used was OsiriX (version 3.3 32-bit). Data were compared with Wilcoxon and McNemar tests at the 5% level.

RESULTS

Bone dehiscence before surgery was present in 26% and 15% of the Class II and III groups, respectively. The presence of dehiscence increased to 31% in the Class II and 20% in the Class III patients after surgery (P < .05).

CONCLUSIONS

The prevalence of dehiscence increased slightly in Class II and Class III surgical-orthodontic patients after orthognathic surgery. Temporary vascular supply reduction and oral hygiene difficulties may explain these results; however, more studies are needed.

Evaluation of enzyme activity and rate of tooth movement in corticotomy-accelerated tooth movement - A randomized clinical trial

BACKGROUND:

This study was undertaken to evaluate the enzyme activity profiles in human saliva and gingival crevicular fluid (GCF) in accelerated tooth movement when compared with normal orthodontic tooth movement (OTM) in extraction cases.

MATERIALS AND METHODS:

Twenty patients who required premolar extractions were treated with MBT mechanotherapy. They were divided into two equal groups: conventional (Group I) and corticotomy (Group II) which was performed on both the jaw sides before initiating retraction. GCF was collected from mesial and distal aspects of canine before initiation of retraction and at 7^th, 14^th, 21^st, and 28^th days, and then at fifth and sixth weeks and third and sixth months after retraction. A total of 5 mL of unstimulated saliva was collected from the subjects after 90 min of nonoral activity (subjects were refrained from eating and drinking).

RESULTS:

The results showed that in Group I, the peak of aspartate aminotransferase (AST) and alkaline phosphatase (ALP) enzyme activity occurred on the 14^th day of force application. In Group II, the enzyme activity progressively increased from day 0 to 6 weeks, peaking at the sixth week, and then a decline in enzyme activity was observed on third and sixth months. When ALP and AST activities in GCF and saliva were compared between Groups I and II, no statistically significant difference was observed on days 0, 7, and 14.

CONCLUSION:

Corticotomy-accelerated tooth movement is a promising technique that has many applications in orthodontic treatment of adults as it helps overcome many of the current limitations of this treatment. The enzymatic activity signifies osteoclastic and osteoblastic activities, so ALP and AST from the saliva and GCF may potentially be used as biomarkers for monitoring corticotomy-assisted OTM.

Interproximal bone in maxillary anterior teeth in subjects with Class III facial deformity: Are there options for segmental maxillary osteotomy in "surgery first"?

Our aim was to give a morphometric description of the interproximal bone between the anterior maxillary teeth of subjects with class III facial deformity, who were candidates for segmented Le Fort I osteotomy. We measured the width of the interproximal bone from the upper right canine to the upper left canine in cone-beam computed tomographic images of 35 subjects, and identified five interproximal areas of measurement. The lower and upper measurements were established 5mm and 10mm from the cervical crest of the interproximal bone. A paired samples t test and Pearson's correlation coefficient were applied and probabilities of less than 0.05 were accepted as significant. In all the scans of interproximal bone, the apical zone was significantly wider than the inferior zone (p<0.001). The area between the central incisors was the widest, with a mean (SD) of 2.42 (0.68) mm in the lower, and 4.27 (0.99) mm in the upper, region followed by the space between the canines and lateral incisors. The minimum interproximal spaces in the lowest area were between 1.1 and 1.5mm, which suggested the potential for damage to the teeth during segmental osteotomy. The interproximal spaces were at potential risk of dental and periodontal injuries, and the area between the central incisors seemed to be most suited to interproximal osteotomies in "surgery first".

Assessment of the effect of the corticotomy-assisted orthodontic treatment on the maxillary periodontal tissue in patients with malocclusions with transverse maxillary deficiency: a case series

Background

The aim of the study was to assess the effect of corticotomy–assisted orthodontic treatment on soft tissue clinical parameters in patients with malocclusions with transverse maxillary deficiency.

Methods

The study included 20 generally healthy adult individuals with malocclusion, who underwent a corticotomy-assisted orthodontic treatment in maxilla. During the corticotomy performed after full-thickness flap elevation, only the buccal cortical plate was cut with the use of OTS-7, OTS7–4, OTS7-3 ultrasound tips of the piezosurgery device (Mectron s. p. a., Italy). A clinical examination was performed prior to the corticotomy procedure, then repeated – 3, 6, 9 and 12 months after the procedure. The following parameters were assessed: FMPI (full mouth plaque index), FMBOP (full mouth bleading on probing), PD (probing depth), CAL (clinical attachment level), GR (gingival recession height), RW (recession width), PH (papilla height), PW (papilla width), BS (bone sounding), biotype and KT.

Results

There was a statistically significant reduction in PD (mean difference: 0.06; 95% Cl: − 0.33, − 0.18), CAL (mean difference: 0.07; 95% Cl: − 0.33, − 0.19), PH (mean difference: 0.26; 95% Cl: − 0.47, 0.05) and BS (mean difference: 0.13; 95% Cl: − 0.41, − 0.14) after the treatment. Statistically significant changes were also noted in relation to KT (mean difference: 0.17; 95% Cl: − 0.07, 0.27) and biotype (mean difference: 0.07; 95% Cl: 0.26, 0.39), which thickness increased significantly after the treatment. No statistically significant differences were observed in GR, RW and PW.

Conclusions

The corticotomy–assisted orthodontic treatment did not jeopardize the periodontal clinical status in maxilla. There is a need for further studies on a larger number of patient to compare the clinical findings with a control group as well as in patients with conventional orthodontic treatment in a longer follow-up time to find out more about the post-treatment periodontal tissue changes and stability.

Cone beam computed tomography evaluation of tooth injury after segmental Le Fort I osteotomy

The purpose of this study was to explore the incidence of injuries to the teeth at the vertical osteotomy line after segmental Le Fort I osteotomy by examination of postoperative cone beam computed tomography (CBCT) images. Data for this retrospective case study were collected using CBCT images of 132 patients with an indication for Le Fort I osteotomy with three-piece segmentation of the maxilla. Twenty-two patients (17%, 95% confidence interval 10-23%) had dental injuries. No patient had more than one dental injury. Thirty-three patients (25%, 95% confidence interval 18-32%) had bone dehiscence of the teeth (defined as the osteotomy line passing through the periodontal ligament). Six patients had bone dehiscence involving two teeth and one patient had bone dehiscence involving three teeth. In the group in which dental injuries occurred, the preoperative interdental distance at the vertical osteotomy line was significantly shorter than the interdental distance in the group without dental injuries. In conclusion, this study demonstrated that a preoperative interdental distance of more than 2.5mm significantly reduced the possibility of tooth injuries adjacent to the vertical osteotomy line during Le Fort I osteotomy with three-piece segmentation of the maxilla.

Maxillary Interdental Osteotomies Have Low Morbidity for Alveolar Crestal Bone and Adjacent Teeth: A Cone Beam Computed Tomography-Based Study

PURPOSE

Maxillary segmentation involving interdental osteotomies can have an adverse effect on the interdental crestal bone and adjacent teeth. The purpose of the present study was to evaluate the effect of interdental osteotomies on surrounding osseous and dental structures, including adjacent teeth, using cone beam computed tomography (CBCT), in patients who underwent segmental maxillary osteotomies.

PATIENTS AND METHODS

The present retrospective cohort study evaluated interdental osteotomy (IDO) sites between the lateral incisors and canines in patients treated with 3-piece Le Fort I osteotomies. CBCT scans were assessed using Kodac Dental Imaging software at specific intervals: T0 (before surgery), T1 (immediately after surgery), and T2 (a minimum of 11 months after surgery). The statistical analysis using a linear regression model was adjusted to compare the variables at the different intervals. Injury to the dental structures was assessed by radiological evidence of dental damage, the requirement for endodontic treatment, or tooth loss.

RESULTS

We evaluated 94 IDO sites in 47 patients in the present study. The mean inter-radicular distance at T0 was 2.5 mm. A statistically significant increase was seen in the inter-radicular distance (between T1 and T0) of 0.72 mm, with a reduction of the alveolar bone crest height (between T2 and T0) of 0.19 mm (P < .001) for the group that underwent IDO. A weak correlation was found for this increase in the inter-radicular distance, with changes in the alveolar crest bone height. The potential complications associated with interdental osteotomies such as iatrogenic damage to the tooth structure, the need for endodontic treatment, and tooth loss were not encountered in any patients.

CONCLUSIONS

We found very low morbidity for the interdental alveolar crest and the integrity of teeth adjacent to interdental osteotomies for patients who underwent maxillary segmentation between the lateral incisors and canines.

Why segment the maxilla between laterals and canines?

Introduction:

Maxillary surgery on a bone segment enables movement in the sagittal and vertical planes. When performed on multiple segments, it further provides movement in the transverse plane. Typical sites for interdental osteotomies are between laterals and canines, premolars and canines, or between incisors. Additionally, osteotomies can be bilateral, unilateral or asymmetric. The ability to control intercanine width, buccolingual angulation of incisors, and correct Bolton discrepancy are some of the advantages of maxillary segmentation between laterals and canines.

Objective:

This article describes important features to be considered in making a clinical decision to segment the maxilla between laterals and canines when treating a dentoskeletal deformity. It further discusses the history of this surgical approach, the indications for its clinical use, the technique used to implement it, as well as its advantages, disadvantages, complications and stability. It is therefore hoped that this paper will contribute to disseminate information on this topic, which will inform the decision-making process of those professionals who wish to make use of this procedure in their clinical practice.

Conclusions:

Segmental maxillary osteotomy between laterals and canines is a versatile technique with several indications. Furthermore, it offers a host of advantages compared with single-piece osteotomy, or between canines and premolars.

Efficacy of the technique of piezoelectric corticotomy for orthodontic traction of impacted mandibular third molars

Our aim was to assess the efficacy of piezoelectric corticotomy for orthodontic traction of mandibular third molars close to the inferior alveolar nerve. Thirty patients with impacted third molars close to the nerve were included in the study, 15 of whom were treated with conventional orthodontic traction and 15 with piezoelectric corticotomy. We recorded duration of treatment including exposure and orthodontic traction, and time to the final extraction. Postoperative complications including trismus, swelling, and pain were also noted. Alveolar bone levels mesial and distal to the second molars were evaluated on cone-beam computed tomographic (CT) images. Student's t test was used to assess the significance of differences between the groups. After orthodontic treatments all impacted third molars were successfully removed from the inferior alveolar nerve without neurological damage. The mean (SD) duration of surgical exposure in the piezoelectric corticotomy group was significantly longer than that in the conventional group (p=0.01). The mean (SD) duration of traction was 4 (2.3) months after piezoelectric corticotomy, much shorter than the 7.5 (1.3) months in the conventional group (p=0.03). There were no significant differences in postoperative complications between the groups. There was a significant increase in the distal alveolar height of second molars after treatment in both groups (p<0.01). We conclude that the use of piezoelectric corticotomy allows more efficient and faster traction of third molars with a close relation between the root and the inferior alveolar nerve, although it took longer than the traditional technique.

Dentoalveolar surgery techniques combined with orthodontic treatment: A literature review

Surgery on the dentoalveolar process combined with orthodontic treatment was emphasized as an alternative method for reducing the treatment time and improving the orthodontic treatment on post-adolescent and adult patients. This combined treatment facilitates and accelerates orthodontic tooth movement. This article reviews the clinical practice in surgery-assisted orthodontic treatment in relation to historical perspective, indications and biological principles, as well as limitations and risks of dento-osseous surgical techniques, including dento-osseous osteotomy and/or ostectomy, dento-osseous microfracture, dento-osseous corticotomy, and/or corticoectomy, and dental distraction.

PAOO technique for the bimaxillary protrusion: Perio-ortho interrelationship

An increasing number of adult patients have been seeking orthodontic treatment, and a short treatment time has been a recurring request. To meet their expectations, a number of innovative techniques have been developed to accelerate orthodontic tooth movement. Significant acceleration in orthodontic tooth movement has been extensively reported following a combination of selective alveolar decortication and bone grafting surgery with the latter being responsible for the increased scope of tooth movement and the long-term improvement of the periodontium. Six patients who have been diagnosed as class I malocclusion with bimaxillary protrusion were selected. A modified corticotomy procedure was carried out The active orthodontic treatment was begun within 1 week after surgery and follow up. All the patients reported the minmalpain and mild swelling 2 days following the surgical procedure. The mean treatment time for these patients was 17.4 months, with the distalization of the canines being mostly completed in 8.5 months. Periodontallyaccelerated osteogenicsorthodontic tooth movement procedure or selective alveolar decortications or corticotomy approach is one of the surgical techniques developed to reduce the time for orthodontic treatment. This newer approach is leading to short orthodontic treatment time and great patient acceptance.

Periodontally accelerated osteogenic orthodontics (PAOO) - a review

With an increasing number of adult patients coming to the orthodontic clinic, the orthodontic professional is constantly looking for ways to accelerate tooth movement. Surgical intervention to affect the alveolar housing and tooth movement has been described in various forms for over a hundred years. However, it is the spirit of interdisciplinary collaboration in orthodontics has expanded the realm of traditional orthodontic tooth movement protocols. Periodontal accelerated osteogenic orthodontics (PAOO) is a clinical procedure that combines selective alveolar corticotomy, particulate bone grafting, and the application of orthodontic forces. This procedure is theoretically based on the bone healing pattern known as the regional acceleratory phenomenon (RAP). PAOO results in an increase in alveolar bone width, shorter treatment time, increased post treatment stability, and decreased amount of apical root resorption. Tooth movement can be enhanced and cases completed with increased alveolar volume providing for a more intact periodontium, decreased need for extractions, degree of facial remodeling and increased bone support for teeth and overlying soft tissues, thereby augmenting gingival and facial esthetics.The purpose of this article is to describe the history, biology, clinical surgical procedures, indications, contraindications and possible complications of the PAOO procedure.

Key words:Periodontics, corticotomy, osteogenic, orthodontics.

Socket sclerosis, a rare complication in orthodontic tooth movement

Socket sclerosis is usually asymptomatic and does not require any treatment. The only potential complication arises during orthodontic treatment, wherein sclerosed socket of the premolar teeth may be an obstacle in closing the space by movement of teeth through the extraction space. This article demonstrates the problems encountered during the orthodontic treatment of a 20-year-old Malaysian woman with socket sclerosis and the treatment strategy employed to overcome the same.

Corticotomy-assisted orthodontic treatment: review

Corticotomy-assisted orthodontic treatment is an established and efficient orthodontic technique that has recently been studied in a number of publications. It has gradually gained popularity as an adjunct treatment option for the orthodontic treatment of adults. It involves selective alveolar decortication in the form of decortication lines and dots performed around the teeth that are to be moved. It is done to induce a state of increased tissue turnover and a transient osteopenia, which is followed by a faster rate of orthodontic tooth movement. This technique has several advantages, including faster tooth movement, shorter treatment time, safer expansion of constricted arches, enhanced post-orthodontic treatment stability and extended envelope of tooth movement. The aim of this article is to present a comprehensive review of the literature, including historical background, contemporary clinical techniques, indications, contraindications, complications and side effects.

Dilemmas in treating a patient with severe bialveolar protrusion and a hyperdynamic lip

A black woman with severe bialveolar protrusion and a hyperdynamic lip on smiling was treated with molar and premolar extractions and orthognathic surgery, including a maxillary 3-piece LeFort, a maxillary segmental osteotomy, a mandibular segmental osteotomy, and a midsymphyseal ostectomy of the mandible.

An adult bimaxillary protrusion treated with corticotomy-facilitated orthodontics and titanium miniplates

We performed an orthodontic treatment combined with corticotomy and the placement of titanium miniplates in an adult patient who desired a shortened treatment period. The patient had an Angle Class I malocclusion with flaring of the maxillary and mandibular incisors. First, titanium miniplates were placed into the buccal alveolar bone of the maxilla for absolute orthodontic anchorage. Second, an edgewise appliance was applied to the maxillary and mandibular teeth. Then, the maxillary first premolars and mandibular second premolars were extracted. At the same time, a corticotomy was performed on the cortical bone of the lingual and buccal sides in the maxillary anterior as well as the mandibular anterior and posterior regions. Leveling was initiated immediately after the corticotomy. The extraction spaces were closed with conventional orthodontic force (approximately 1 N per side). The edgewise appliance was adjusted once every 2 weeks. The total treatment time was 1 year. Cephalometric superimpositions showed no anchorage loss, and panoramic radiographs showed neither significant reduction in the crest bone height nor marked apical root resorption. A corticotomy-facilitated orthodontic treatment with titanium miniplates might shorten an orthodontic treatment period without any anchorage loss or adverse effects.

Complications associated with segmentation of the maxilla: a retrospective radiographic follow up of 82 patients

The aim of the present study was to retrospectively examine the clinical and radiographic incidence and frequency of injuries to teeth and their surrounding tissues adjacent to interdental osteotomies in conjunction with segmentation of the maxilla. Vertical interdental osteotomies have been performed in combination with Le Fort I osteotomy for correction of various dento-facial deformities. All our orthognathic patients are followed prospectively in a standardized manner. Eighty-two consecutive patients who underwent dento-facial correction by segmented maxillary osteotomy alone or in combination with simultaneous mandibular surgery between 1992 and 1998 were included in the study. They were followed for up to 30 months postoperatively. A total of 158 interdental osteotomies were performed, involving a total of 316 teeth. Only a small number of complications such as osteolytic processes, marginal bone destruction, root resorption or mechanical injuries to the teeth were seen.

Marginal bone level after Le Fort I osteotomy

The object of the study was to assess the effect of Le Fort I osteotomy and maxillary interdental osteotomy on the marginal bone level. Forty patients (25 female, 15 male, mean age 24 years, range 15-46) treated for dentofacial deformities comprised the subjects of the study and underwent Le Fort I osteotomy with or without simultaneous interdental osteotomy. Outcome was measured by marginal bone level measured in radiographs before and 1 year after operation. All patients had good oral hygiene. There was an overall significant mean marginal bone loss of 0.2 mm at surfaces without interdental osteotomy (P = 0.001). When the bone loss of the different types of teeth was considered separately, only those of central incisors (0.5 mm, P = 0.0001) and canines (0.4 mm, P = 0.004) were significant. Interdental osteotomy caused an overall mean marginal bone loss of 0.4 mm, but this was not significantly different from that of teeth without interdental osteotomy (P = 0.07). When the bone loss of different types of teeth after interdental osteotomy was considered separately, the only difference that achieved significance was that of premolars (0.3 mm, P = 0.04). Though there were significant differences, none of them was large enough to have any clinical relevance. Le Fort I osteotomy and interdental osteotomy may only in a few instances cause marginal bone loss of clinical relevance. However, the present study was performed on patients with good oral hygiene. The above conclusions may therefore not be valid for patients who, prior to surgery, already have a compromised marginal bone level.

Irreversible pulpal damage of teeth adjacent to recently placed osseointegrated implants

Three cases of necrosis of previously vital teeth next to osseointegrated implant insertion sites are presented. In two cases, the teeth were in the anterior part of the lower jaw and exhibited the same pattern of evolution of pulpal damage (i.e. a relatively short time to become nonvital).

Pulpal and apical changes secondary to segmental osteotomy in the mandible--an experimental study

Posterior segmental osteotomies were performed on 7 dogs to investigate postoperative changes in the pulpal and periodontal tissue. Osteotomy cuts were made at various distances from the apices of roots. After 3 to 6 months, results were evaluated clinically, radiographically and histopathologically. Clinical and radiographic healing of the osteotomy sites was uneventful. Histological evaluation revealed that when the osteotomy cuts were made at a safe distance (3-5 mm) from the apices of roots, neither important pulpal degeneration nor loss of teeth occurred. Even two of the teeth whose apices were cut off had completely healthy pulpal and periapical tissues. The periodontium in almost all of the cases was also found to be healthy.

Stability of mandibular constriction with a symphyseal osteotomy

The purposes of this study are to determine the stability of surgical mandibular constriction with a midline osteotomy and to evaluate the periodontal and temporomandibular joint responses. A symphyseal osteotomy to facilitate mandibular construction was performed in 15 patients to correct transverse discrepancies. At the same time a surgical anterior or posterior repositioning of the mandible was done by using a bilateral sagittal osteotomy of the vertical ramus. Tomograms in the coronal plane including the mandibular second molars were taken preoperatively (T1), immediately postoperatively (T2) and 8 weeks postoperatively (T3). Linear measurements between the cortical borders of the mandible were assessed from the tomograms at each time period. Median surgical and postoperative changes in mandibular width were determined. When evaluating the entire group no statistically significant change in the surgical constriction was found postoperatively (T2 and T3), although there was some individual variability. An examination of the periodontal response at the osteotomy site revealed no statistically significant change between the initial and the 5-month postoperative examinations. No changes in joint noise were detected postoperatively, and all mandibular joint movements returned to preoperative values except for excursive movements. Mandibular constriction with a midline osteotomy on conjunction with a bilateral sagittal osteotomy was found to be a stable modality for correcting transverse disharmonies.

Aseptic necrosis following maxillary osteotomies: report of 36 cases

The sequelae of insufficient vascularity following maxillary orthognathic surgery can vary from loss of tooth vitality, to periodontal defects, to tooth loss, to loss of major maxillary dentoalveolar segments. The results of a questionnaire mailed to oral and maxillofacial surgeons found this complication was most likely to occur with Le Fort I osteotomies done in multiple segments in conjunction with superior repositioning and transverse expansion. Significant palatal perforations definitely seem to compromise the already tenuous blood supply to the anterior maxilla. Suggestions are given regarding the prevention and treatment of this complication.

Diagnosis and treatment planning for mandibular subapical osteotomies with new surgical modifications

Mandibular anterior subapical osteotomies have been used for many years and have usually included vertical interdental osteotomies and submandibular horizontal osteotomies stabilized with intraosseous wires, splints, and bridle wires around the teeth adjacent to the interdental osteotomies. This article presents pertinent diagnostic criteria, orthodontic and surgical treatment planning considerations, and new surgical modifications to alter the position of the mandibular anterior teeth.

Periodontal implications of orthodontic treatment in adults with reduced or normal periodontal tissues versus those of adolescents

This longitudinal study monitored periodontal status in 20 adults and 20 adolescents undergoing fixed orthodontic treatment. Ten adults had generalized periodontitis and received periodontal treatment, including periodontal surgery, before orthodontic treatment. They also received periodontal maintenance at 3-month intervals during orthodontic treatment. The other 10 adults had normal periodontal tissues. Neither these latter adults nor the adolescents received periodontal maintenance during orthodontic treatment. Periodontal status was determined (1) at six standard sites before fixed appliances were placed (baseline), (2) at 1, 3, 6, 9, 12, and 18 months after appliances had been placed, and (3) 1, 3, 6, and 12 months after appliances had been removed. At each of these visits, these sites were assessed for plaque index, gingival index, bleeding tendency, and pocket depth. Loss of attachment between baseline and 3 months after appliances were removed and tooth loss were also determined. Complete data were obtained for 15 adolescents and 14 adults. During orthodontic treatment the adolescent group showed significantly more (p less than 0.05) periodontal inflammation and supragingival plaque than the adults; after appliances were removed, this pattern was no longer statistically significant. For loss of attachment, there were no significant differences among adolescents, adults with normal periodontal tissues, or adults with reduced but healthy periodontal tissues who had undergone treatment for periodontal disease. For tooth loss, three nonstudy site teeth with pockets deeper than 6 mm and/or furcation involvements were lost because of periodontal abscesses in the adult group treated for periodontal disease.