Non-ossifying fibroma (metaphyseal fibrous defect) of the mandible

A 15-year-old young man was referred for evaluation of a non-tender swelling of the left mandibular angle region. A non-ossifying fibroma was diagnosed. The lesion was enucleated under general anesthesia. The postoperative course was uneventful. There have been no signs of recurrence, and there was complete bone regeneration in the region 24 months after operation. This report also reviews other fifteen cases of non-ossifying fibroma in the mandible reported in the literature.

Implant vs abutment level connection in implant supported screw-retained fixed partial dentures with cobalt-chrome framework: 1-year interim results of a randomized clinical study

BACKGROUND

Screw-retained fixed partial dentures (FPD) have shown a lower incidence of biologic complications and an easier retrievability compared with cemented FPD.

PURPOSE

To compare the marginal bone loss at conical connection implant restored with a screw retained cobalt-chrome FPD in an implant-level (IL) or an abutment-level (AL) setup.

MATERIALS AND METHODS

Patients with at least two adjacent missing teeth were randomly allocated to be restored with IL or AL FPD. Periapical radiographs and clinical examination were taken at implant placement, prosthetic connection, 6 and 12 months to evaluate marginal bone loss (MBL), and soft tissue conditions. Complications were used to calculate prognostic indexes.

RESULTS

Fifty patients were treated with 50 FPD supported by 119 implants. The difference of MBL between the IL and AL groups was statistically significant (P = 0.003). At 1 year, MBL was 0.086 ± 0.313 mm and 0.005 ± 0.222 mm in the IL and AL groups, respectively. The presence of BoP increased with time in IL, whereas it decreased in AL group (P < 0.001). A minor complication was encounted in one FPD.

CONCLUSIONS

A low grade of MBL was present after 1 year. IL showed greater amount of MBL and soft tissue inflammation indexes than AL. In FPD, AL may be a safer procedure than IL setup in order to preserve a healthy periimplant tissue.

Small central odontogenic fibroma mimicking hyperplastic dental follicle and dentigerous cyst

Central odontogenic fibroma has been defined as a benign odontogenic tumor, representing the intraosseous counterpart of a peripheral odontogenic fibroma. The odontogenic fibroma is a rare tumor. Differential diagnosis of radiolucent lesions in the molar-premolar region of mandible which involve impacted tooth may include central odontogenic fibroma, hyperplastic dental follicle, dentigerous cyst, unicystic ameloblastoma, and keratocystic odontogenic tumor. We describe an example of a small central odontogenic fibroma mimicking hyperplastic dental follicle and dentigerous cyst, resulting in uneruption of a primary tooth.

Surface structure and mechanical properties of impaction-modified Y-TZP

OBJECTIVES

The objectives of the study were to describe the surface structure and the chemical surface composition of Y-TZP ceramics produced by using the modified additive technique and to evaluate the flexural strength of Y-TZP with or without surface modification and with different pretreatments: etching before or after sintering combined with or without an adhesive cement system.

METHODS

Y-TZP discs were used for surface analysis (n=48) and for biaxial flexural strength testing (n=200). The specimens were divided into groups depending on the cementation surface of Y-TZP: unmodified, sandblasted or glass-modified Y-TZP surfaces, and according to the production process: etching before or after sintering.

RESULTS

The surface structure and the chemical composition of glass-modified Y-TZP differ; a rougher surface and phase transformation was identified compared to unmodified Y-TZP. The unmodified Y-TZP groups showed significantly higher flexural strength compared to the glass-modified groups (p<0.001) and showed increased flexural strength after sandblasting (p<0.001). Furthermore, by adding cement to the surface, the value increased even further in comparison with the sandblasted non-cemented specimens (p<0.01). After thermocycling, however, the cement layer on the unmodified and the sandblasted surfaces had air pockets and regions with loose cement.

SIGNIFICANCE

A rougher surface structure, superficial glass remnants and a higher content of m-phase was present in the cementation surface of glass-modified Y-TZP. The glass modification creates a bondable cementation surface that is durable. By etching the glass-modified Y-TZP before sintering, a more homogenous surface is created compared to one that is etched after sintering.

Maxillary sinus aplasia

PURPOSE

A case of unilateral aplasia is reported. Associated anatomical anomalies and review of the literature is described, and a comparison with maxillary sinus hypoplasia is made.

PATIENT

A 40-year-old male was complaining of an esthetic "defect" in his face. There was an antero-posterior depression in the left infraorbital region. Computed tomography showed absence of the left maxillary antrum, uncinate process, and maxillary infundibulum. The ipsilateral orbit was increased in volume inferiorly, and the inferior margin was immediately adjacent to the root of the inferior turbinate. The left inferior and middle turbinate was hyperplastic. The nasal septum was a little dislocated to the ipsilateral side. There was no history of antecedent sinusitis or surgery, and no evidence of systemic disease. An appositional en bloc autogenous bone graft was placed on the left infraorbital depression.

CONCLUSIONS

With precise computed tomography assessments, a maxillary sinus hypoplasia or aplasia can be diagnosed and distinguished from other maxillary sinus anomalies, and may help the surgeon to plan his surgical procedure and identify the limits of dissection accordingly. The condition can also "cause" an esthetical deficit in the infraorbital/zygomatic region, which can be resolved with an appositional graft.

A History of Periodontitis Suggests a Higher Risk for Implant Loss

ARTICLE TITLE AND BIBLIOGRAPHIC INFORMATION

Periodontitis, implant loss and peri-implantitis. A meta-analysis. Sgolastra F, Petrucci A, Severino M, Gatto R, Monaco A.Clin Oral Implants Res 2015;26(4):e8-16.

REVIEWER

Bruno Ramos Chrcanovic, DDS, MSc, PhD student

PURPOSE/QUESTION

To compare the risks of implant loss, implant bone loss, and peri-implantitis between subjects with and without a history of periodontal disease.

SOURCE OF FUNDING

The authors reported that no external funding sources directly supported this study

TYPE OF STUDY/DESIGN

Systematic review with meta-analysis of data

LEVEL OF EVIDENCE

Level 2: Limited-quality, patient-oriented evidence

STRENGTH OF RECOMMENDATION GRADE

Grade B: Inconsistent or limited-quality patient-oriented evidence.

Immediate implant placement in the posterior mandible: A cone beam computed tomography study

OBJECTIVE

To determine the longest upright and tilted implant that can be placed in posterior mandibular teeth (second premolars [2PM], first molars [1M], and second molars [2M]) in case of immediate implant placement (IIP), respecting a safe distance from the inferior alveolar canal (IAC) and the submandibular fossa, using cone beam computed tomography (CBCT) scans.

METHOD AND MATERIALS

In CBCT scans of 118 subjects, the following were measured: distance from the tooth apex to the IAC (DTC), lateromedial width of the mandible, classification of mandibular cross-sectional morphology, upright and tilted implant placement simulation, tilting angle that allowed placement of the longest implant.

RESULTS

The DTC has shown to be greater for 1M, shorter for 2PM, and even shorter for 2M. Between 70% and 88% of all 2PM, 1M, and 2M present less than 6 mm of DTC. The cross-sectional morphology of the mandible had a tendency to be classified as "undercut" in more posterior regions. For both 4.0- and 5.0-mm implants, more posterior regions resulted in a greater difference in length between the upright and tilted implants. The tilting angle was greater for the more posterior regions. Most of the relationships between age/sex and the morphometric parameters were weak.

CONCLUSION

Lingual concavity is a common clinical finding at the posterior mandibular region, and its occurrence varies according to the tooth type. The great majority of the 2PM, 1M, and 2M present limited available bone between the root apex and the IAC, which stresses the need for careful attention when IIP is planned in this area.

Immediate Loading of Single Implants, Guided Surgery, and Intraoral Scanning: A Nonrandomized Study

PURPOSE

To compare clinical and esthetic outcomes between immediately loaded single implants placed with and without a fully guided surgical procedure.

MATERIALS AND METHODS

Patients with a missing maxillary tooth (second premolar to second premolar) were considered for inclusion in this 1-year prospective nonrandomized study. Exclusion criteria were general health contraindications for oral surgery besides the need for bone grafting or ridge augmentation. One group received digital implant planning, fully guided surgery, and immediate loading (DIL). The other group received freehand surgery and immediate loading (IL). Outcome measures were implant survival, marginal bone loss, soft tissue changes, papilla index, pink and white esthetic scores (PES and WES, respectively), and patient-reported outcome measures (PROMs).

RESULTS

Two of 21 implants failed in the DIL group soon after placement, resulting in a 1-year implant survival rate of 90.5%, while no implants failed in the IL group. Significantly higher papilla index scores and lower soft tissue changes were found for the DIL group compared to the IL group. No differences were found after 1 year regarding marginal bone loss, PES, WES, or PROMs.

CONCLUSION

Within the limitations of this study, immediate loading in combination with fully guided surgery might negatively affect implant survival. Immediate loading, fully guided surgery, and a digital workflow appear to have a positive effect on early soft tissue adaptation.

Clinical factors associated with the recurrence of central giant cell lesions

Central giant cell lesion of the jaws (CGCLJ) is a destructive condition that shows a varied and unpredictable biological behaviour. In the present study, we aimed to evaluate factors associated with the recurrence of CGCLJ. Based on the data of a previous systematic review of 2270 cases of CGCLJ, we used the multiple imputation to deal with the missing data. The dependent variable was the recurrence after the first treatment (yes/no). The dichotomic covariates were sex, upper or lower jaw location, size (up to or larger than 4 cm), pain, cortical bone perforation (yes/no), locularity (uni-/multilocular), tooth displacement (yes/no), treatment type (curettage or enucleation) and root resorption (yes/no). The final logistic model indicated that the tumours associated with tooth displacement, root resorption and treated with curettage had a more significant chance of recurrence. In conclusion, our study suggests that tooth displacement, root resorption and the type of treatment are potentially useful in the future construction of an algorithm for patient's treatment.

Tracheotomy for a foreign body in the larynx

INTRODUCTION

In the normal population, inadvertently swallowed foreign objects enter the gastrointestinal tract more frequently than the tracheobronchial tree. There is a typical patient population that is at higher risk for aspiration.

DISCUSSION

Sequelae may range from relatively benign partial obstruction to the immediately life-threatening total airway obstruction. Foreign objects lodged in the upper aspect of the trachea may be retrieved with simple instrumentation.

CONCLUSION

Some cases may complicate and may require direct access through a tracheotomy, as the case shown in this paper.

Ameloblastic fibrodentinosarcoma and ameloblastic fibro-odontosarcoma: A systematic review

The purpose of the present review was to integrate the available data published on ameloblastic fibrodentinosarcoma (AFDS) and ameloblastic fibro-odontosarcoma (AFOS) into a comprehensive analysis of their clinical/radiologic features. An electronic search was undertaken in July/2017. Eligibility criteria included publications having enough clinical/radiological/histological information to confirm the diagnosis. Seventeen publications (8 AFDS, 9 AFOS) were included. The patients with the two different lesions had a similar mean age. The lesions were both more prevalent in mandibles than in maxillae, all showed bone expansion and similar rates of cortical bone perforation, tooth displacement, and locular appearance at radiological exams. Mean follow-up time was higher for AFDS, and the mean size of the lesions were larger for AFDS, although without a statistically significant difference. None of AFDS recurred, while 2 AFOS recurred. As only few cases of AFDS and AFOS have been reported, additional reports are necessary to add evidence to the study of clinical and radiologic features of these lesions.

Bisphosphonates and dental implants: A meta-analysis

OBJECTIVE

To test the null hypothesis of no difference in the implant failure rates, marginal bone loss, and postoperative infection for patients receiving or not receiving bisphosphonates, against the alternative hypothesis of a difference.

METHOD AND MATERIALS

An electronic search was undertaken in October 2015 in PubMed/Medline, Web of Science, and Embase, plus hand-searching and databases of clinical trials. Eligibility criteria included clinical human studies, either randomized or not.

RESULTS

A total of 18 publications were included in the review. Concerning implant failure, the meta-analysis found a risk ratio of 1.73 (95% confidence interval [CI] 1.21-2.48, P = .003) for patients taking bisphosphonates, when compared to patients not taking the medicament. The probability of an implant failure in patients taking bisphosphonates was estimated to be 1.5% (0.015, 95% CI 0.006- 0.023, standard error [SE] 0.004, P < .001). It cannot be suggested that bisphosphonates may affect the marginal bone loss of dental implants, due to a limited number of studies reporting this outcome. Due to a lack of sufficient information, meta-analysis for the outcome "postoperative infection" was not performed.

CONCLUSION

The results of the present study cannot suggest that the insertion of dental implants in patients taking BPs affects the implant failure rates, due to a limited number of published studies, all characterized by a low level of specificity, and most of them dealing with a limited number of cases without a proper control group. Therefore, the real effect of BPs on the osseointegration and survival of dental implants is still not well established.

Long-term retrospective clinical study of tooth-supported fixed partial dentures: A multifactorial analysis

PURPOSE

To assess the influence of several factors on the survival of tooth-supported fixed partial dentures (FPDs) with vital and non-vital abutments.

METHODS

The present retrospective cohort study was based on the records of patients treated with 3-to-7-unit tooth-supported FPDs with a minimum follow-up time of 6 months after prosthesis delivery. Cumulative survival rate (CSR) was calculated over the maximum follow-up period. Cox regression models were used to evaluate the association between the clinical covariates and prosthesis failure.

RESULTS

A total of 331 FPDs in 229 patients were included. The CSRs were 90.1% and 77.6% after 5 and 10 years and 67.9% and 52.1% after 15 and 20 years, respectively. Tooth-supported FPD failure was more prevalent within the first years of prosthesis delivery. Loss of one or more abutment teeth and loss of prosthesis retention were the main reasons for failure. Smoking and type of prosthesis material significantly influenced the survival of FPDs. Abutment vitality, position of the non-vital abutment, or prosthesis length did not show any significant influence on the occurrence of prosthesis failure.

CONCLUSIONS

Smoking and the type of prosthesis material are suggested to contribute to an increased rate of FPD failure irrespective of abutment vitality.

Frequency of Smoking and Marginal Bone Loss around Dental Implants: A Retrospective Matched-Control Study

This dental record-based retrospective study aimed to compare the marginal bone loss (MBL) around dental implants in a group of smokers in relation to a matched group of non-smokers, with a special focus on five different frequencies of daily smoking (non-smokers, and frequency of 1-5, 6-10, 11-15, and 20 cig./day). Only implants with a minimum of 36 months of radiological follow-up were considered. Univariate linear regression models were used to compare MBL over time between 12 clinical covariates, after which a linear mixed-effects model was built. After matching of the patients, the study included 340 implants in 104 smokers, and 337 implants in 100 non-smokers. The results suggested that smoking degree (greater MBL for higher degrees of smoking), bruxism (greater MBL for bruxers), jaw (greater MBL in maxilla), prosthesis fixation (greater MBL for screw-retained prosthesis), and implant diameter (greater MBL for 3.75-4.10 mm) had a significant influence on MBL over time. There appears to be a positive correlation between the degree of smoking and the degree of MBL, meaning, the higher the degree of smoking, the greater the MBL. However, the difference is not apparent for different degrees of smoking when this is high, namely above 10 cigarettes per day.

Retrospective study comparing the clinical outcomes of bar-clip and ball attachment implant-supported overdentures

The aim of this study was to compare the clinical outcomes of implant-supported overdentures (ODs) with either bar-clip or ball attachments. The implant, prosthesis failure, and technical complications were the outcomes analyzed in this retrospective clinical study conducted in a specialty clinic. Seventy-five patients with 242 implants supported by 76 ODs (36 maxillary, 40 mandibular) were included in the study and followed up for 88.8 ± 82.9 months (mean ± standard deviation). Bar-clip and ball attachments were used in 78.9% and 21.1% of the cases, respectively. Forty-three implant failures (17.8%) in 17 prostheses (17/76; 22.4%) were observed in this study. The average period of implant failure was 43.3 ± 41.0 months, and most of them were maxillary turned implants. The bar-clip system demonstrated more complications in the attachment parts compared to the ball attachment system. Poor retention of the prosthesis was similar between the two systems. Loss of implants resulted in the failure of 10 ODs in this study. ODs opposed by natural dentition or fixed prostheses presented with more complications. The Cox proportional hazards model did not show a significant effect on prosthesis failure for any of the factors. These findings indicated that patients with ODs need constant maintenance follow-ups to address the technical complications and perform prosthodontic maintenance regardless of the attachment system used.

Chemical and Topographic Analysis of Eight commercially Available Dental Implants

BACKGROUND

Surface characterization of dental implants allows us to better understand the effects of the implant on the host biological response. In this study, we analyzed and compared these characteristics among implants commercially available in South Africa.

MATERIALS AND METHODS

Eight implants from different manufacturers were chosen for analysis (Touareg, ICE, (R)Evolutions, Uniti, AnyRidge, MIS, Ivory-QSI, Southern), using scanning electron microscopy (SEM), interferometry, and energy dispersive X-ray spectroscopy to study the surface chemical composition and morphology.

RESULTS

The results indicate that variations in manufacturer processes result in implant surfaces that are distinctly different from one another. Most implants presented a moderately rough surface with sandblasted-only implant surfaces having a lower mean value of Sa when compared with sandblasted and acid-etched surfaces. Carbon contamination was detected on all the implants and that of aluminum on five implant surfaces. Ca and P were detected on the surface of Touareg implants, indicating the manufacturer's attempt to enhance osseointegration.

CONCLUSION

The surface of the implants showed a range of chemical, physical properties, and surface topographies.

CLINICAL SIGNIFICANCE

The results indicate that implant surface treatment is not standardized. This may have clinical implications. Further clinical research is required.

Traumatic displacement of maxillary permanent incisor into the nasal cavity

PURPOSE

The purpose of this paper was to describe a case of unviable alveolar repositioning of an intruded tooth into the nasal cavity and to bring the subject of intrusive tooth injury among patients with dentoalveolar fractures to the attention of trauma surgeons.

PATIENT

A 26-year-old male was involved in a car accident and crashed his mouth against the dashboard due to sudden deceleration. Intraoral examination revealed an anterior maxillary dentoalveolar fracture and absence of the central maxillary incisors, right lateral maxillary incisor, and left maxillary canine. Computed tomography showed a dislocated tooth in the nasal cavity. The "missing" left maxillary canine was easily recovered from the floor of the left nostril.

CONCLUSIONS

Because complete dislocation of a tooth can cause a frontal sinus abscess, an airway complication, a respiratory tract obstruction, and a complicated lung abscess or sinusitis, anytime a tooth is not accounted for after a dentoalveolar trauma, the possibility that it has been fully intruded should be considered. Computed tomographic scan should be a routine diagnostic study in all cases with associated missing anatomical structures in the oral and maxillofacial region. The need to involve the dental professional in the initial assessment of dental trauma in emergency rooms in hospitals is important in order to identify how many teeth might be missing after dental trauma and to correctly reposition the avulsed teeth when possible.

Comparison of survival outcomes between ameloblastic carcinoma and metastasizing ameloblastoma: A systematic review

PURPOSE

To investigate and compare the demographic data, occurrence of recurrence and metastasis, and survival prognosis between ameloblastic carcinoma (AC) and metastasizing ameloblastoma (MA), based on appropriate and currently accepted eligible diagnostic criteria, in a systematic review of the literature.

METHODS

An electronic search was undertaken, last updated in December 2021. Eligibility criteria included publications having enough clinicopathological information to confirm the diagnosis of these tumors.

RESULTS

Seventy-seven publications reporting 85 ACs and 43 MAs were included. Both tumors were more frequent in mandible and showed different clinical profiles regarding patients' sex and age. There was no difference in the estimated cumulative survival between patients diagnosed with these tumors. Metastases mainly affected the lungs, followed by cervical lymph nodes. The mean time between the first metastasis and the last follow-up was higher for MA (p = 0.021). In addition, MA patients remained alive longer than AC patients after the first metastasis diagnosis (p = 0.041). Considering only the cases that metastasized, a higher ratio of AC patients died in comparison to MA patients (p = 0.003). The occurrence of recurrence was associated with a conservative primary treatment with both AC (p < 0.001) and MA tumors (p = 0.017). Multiple recurrent events were associated with conservative primary therapies with MA (p < 0.001) but not with AC (p = 0.121).

CONCLUSION

In addition to some demographic differences, ACs that metastasize present a worse prognosis than MA. As conservative procedures are associated with multiple recurrent events, this treatment modality should be avoided for both tumors.

Retrospective clinical study of tooth-supported single crowns: A multifactor analysis

The purpose of the study was to investigate the influence of multiple factors on the survival of tooth-supported single crowns and assess the biological and technical complications. This retrospective study included patients rehabilitated with single crowns with a minimum follow-up time of 6 months after delivery. The cumulative survival rate was calculated over the maximum period of follow-up time and reported in a life-table survival analysis. Univariate and multivariate Cox regression was used to evaluate the associations between clinical covariates and crown failure. The included cohort group consisted of 1037 single crowns delivered in 401 patients and followed for a mean of 134.8 ± 80.2 months. Cumulative survival rate was 89.9% and 80.9% after 5 and 10 years and 70.5% and 61.8% after 15 and 20 years, respectively. The main reasons for single crown failure were loss of retention, tooth loss, and fracture. Anterior placement, non-vital abutments, and bruxism significantly influenced the survival of single crowns. The survival of single crowns was not influenced by patient's age and sex, location of the crowns in relation to the jaws, type of tooth, presence of post and core, and type of crown material, treatment providers, or smoking. Anterior placement, non-vital abutments, and bruxism are factors suggested to increase the risk of single crown failure and the prevalence of technical and biological complications.

Positioning accuracy assessment of minimally invasive percutaneous injection techniques for the treatment of temporomandibular disorders

OBJECTIVE

The aim of the present study was to evaluate the accuracy of an extraoral CBCT-planned 3D-printed surgical guide aimed to percutaneous injection of substances into the temporomandibular joint (TMJ) and the lateral pterygoid muscle (LPM).

METHODS

Nine human cadaver heads were used. Pre-planning CBCT and facial scans were obtained and three percutaneous injection sites were planned: one for the lower compartment of the TMJ and two for the LPM. A digital surgical guide was then designed with small titanium sleeves and printed by a 3D printer. After the injections, new CBCT scans with the needles in place were obtained in order to assess the accuracy of the procedure in relation to the virtual planning.

RESULTS

The mean values for angle deviation were very low (range 1.13o-4.08o), the same happening for the mean difference in the length reached (range 1.82-2.64 mm), as well as for the mean difference in the needle tip dislocation (range 0.94-2.03 mm).

CONCLUSION

The guide seems to be a reliable tool for accurate percutaneous injection of drugs into the inferior compartment of the TMJ and the LPM. Further studies are necessary to test the efficacy and validate the method in an in vivo study.

Evaluation of the effect of self-cutting and nonself-cutting thread designed implant with different thread depth on variable insertion torques: An histomorphometric analysis in rabbits

PURPOSE

To evaluate of the effect of self-cutting and nonself-cutting thread designed implant with different thread depth on variable insertion torques. To evaluate the bone volume (BV) and bone to implant contact (BIC) in these variables MATERIALS AND METHODS: Mainly two thread design, V-shaped thread which is self-cutting and power thread design, which is nonself-cutting implants were considered for this study with a variation in thread depth of 0.4 and 0.6 mm for both the designs, respectively. A total of 32 CAD designed machined surface implant prototypes were manufactured of 4 mm in diameter and 8 mm in length were made, which were machined surfaced, which was placed in the femur of 16 New Zealand white rabbits. These were categorized under 2 groups; Group 1 and Group 2 with insertion torques of <30 and >50 Ncm, respectively. After 4 weeks of healing, rabbits were sacrificed and histomophometric and histologic analyses were done to evaluate the bone response.

RESULTS

Significantly, more BIC was recorded for high torque implants compared with low torque in power-shaped thread design (P value = .01*). BV for new bone formation was statistically significant for V-shaped thread design in high torque when compared with low torque (P value = .02*).

CONCLUSION

The effect of the depth of the thread design was significant for the power-shaped design in enhancing BIC when compared with V-shaped thread design. With high torque V-shaped thread design had more new bone formation as compared with power-shaped thread design.

Assessment of hematologic parameters before and after bimaxillary orthognathic surgery

PURPOSE

The purpose of the study was to evaluate changes of hematologic parameters in bimaxillary surgery.

METHODS

Fifty-three patients were prospectively evaluated and divided into groups based on the surgical procedure and sex (predictor variables). Hemoglobin, red blood cells, hematocrit, and platelet were the primary outcome variables, operation time the secondary outcome, and the patients' age and weight the other variables.

TRIAL REGISTRATION

NCT02364765 (U.S. National Institutes of Health, clinicaltrials.gov).

RESULTS

There was statistically significant difference between all hematologic parameters before and after surgery, for both men and women, and for all surgical groups. There was a positive correlation between operative time and the decrease (in %) of the hematologic parameters. Linear regression analysis suggested that the Hb values decrease 0.083 % for every minute increase in the operation time, and 0.066, 0.066, and 0.010 % for RBC, Hct, and platelet count, respectively. There was a negative correlation between weight and all hematologic parameters. Correlations between age and hematologic parameters were not statistically significant. Almost all correlations between age, weight, sex, and the surgery group and the hematologic parameters were considered as very weak. Only one patient was transfused.

CONCLUSIONS

It is suggested that operation time and patient's weight play a bigger role than patient's age and sex in the decrease of hematologic parameters after bimaxillary surgery.