Biomedical subjects

Hom-Lay Wang

Publications and source records attributed to Hom-Lay Wang.

At least 19 recordsLinked to original sources

PubMed2007

Clinical significance of incision location on guided bone regeneration: human study.

BACKGROUND: Membrane exposure has been associated with poor clinical outcomes in guided bone regeneration. This prospective human study examined the effect of incision locations on flap survival and membrane exposure. METHODS: Twenty-nine implant-associated buccal dehiscence defects in 25 patients were augmented using particulate mineralized human allograft. Ten sites received a collagen bioabsorbable membrane, 10 sites received acellular dermal matrix, and nine sites were treated with bone graft alone. All implants achieved primary stability and passive flap tension at the time of flap closure. Incision location was measured as the distance from the initial incision line to the mucogingival junction. The same measurements were made at 2 weeks and 1 month to represent the length of the flap that survived. The length of the flap that survived at 2 weeks was compared to the mean width of buccal keratinized gingiva (KG) of adjacent teeth. Other clinical parameters recorded included incidence of early membrane exposure and gingival thickness at mid-crest and 6 mm buccal and lingual to the mid-crest at baseline. RESULTS: At 2 weeks, 10 sites experienced early exposure. Exposed sites that were not covered by 1 month remained exposed. Membrane-treated groups showed no significant difference between the width of adjacent buccal KG and the length of the flap that survived at 2 weeks. The length of the flap that survived beyond the mean width of adjacent KG was significantly greater for the graft alone group (1.6 +/- 0.4 mm; P = 0.002). When the gingival thicknesses of exposed and non-exposed cases were compared, only palatal/lingual gingival thickness showed a significant difference (P = 0.002). CONCLUSIONS: Within the limits of the study, it was concluded that the location of the crestal incision might be a significant factor in reducing the incidence of membrane exposure by minimizing flap necrosis. The mean KG width of adjacent teeth may be used as a guide to determine the initial incision location. However, this effect may be less significant in palatal/lingual gingiva >3.0 mm.

Adult↗

PubMed2006

The comparison of provisional luting agents and abutment surface roughness on the retention of provisional implant-supported crowns.

STATEMENT OF PROBLEM: In immediate implant loading, it is important to keep provisional restorations in place during early-phase healing. Current luting agents for provisional restorations may provide inadequate retention, creating a clinical challenge. PURPOSE: This study compared the retention of provisional autopolymerizing acrylic resin implant-supported single restorations with combinations of different implant abutment surface conditions and provisional luting agents. MATERIAL AND METHODS: Thirty solid titanium implant abutments (ITI), 4 mm high, were divided into 3 groups. Ten abutments were unaltered, 10 were airborne-particle abraded with 50-microm aluminum oxide, and 10 were roughened with a medium-roughness diamond rotary cutting instrument. Thirty implant analogs (ITI) were mounted in autopolymerizing acrylic resin blocks. A solid titanium implant abutment was placed in each implant analog and torqued to 35 N.cm. After fabrication of 4 provisional acrylic resin crowns for each abutment, provisional luting agents TempBond, TempBond NE, Life, and Zone were used to secure the provisional crowns to the respective abutments. All specimens were luted with one of the provisional luting agents for a given test. After ultrasonic cleaning of the abutments, another provisional crown was luted with another luting agent. All specimens were stored in 100% humidity environment for 1 day at 37 degrees C prior to testing. Each provisional acrylic resin crown was pulled from the abutment with a 500-kg load cell in a universal testing machine at a crosshead speed of 0.5 cm/minute, and tensile strength was recorded (N). Data were analyzed using analysis of variance (ANOVA) and the Scheffe test (alpha=.05). RESULTS: Tensile strength was significantly higher for Life and TempBond NE than for TempBond and Zone, regardless of the surface conditions (P=.0001). The result of the 2-way ANOVA indicated that a significant interaction existed between the provisional luting agents and surface conditions (P=.0039). TempBond NE showed significantly higher tensile strength when combined with airborne-particle-abraded surfaces compared to other combinations (P=.011). However, no difference was found in tensile strength of Life and Zone between different combinations. The tensile strength of TempBond was lower when used with the unaltered surface compared to other combinations (P=.001). CONCLUSION: Surface modification of an implant abutment by airborne-particle abrasion or diamond rotary cutting instrument did not improve retention of a provisional acrylic crown when Life or Zone was used as the luting agent. Airborne-particle abrasion may be an effective method to increase retention of a provisional acrylic crown when TempBond NE is used.

Acrylic Resins↗

PubMed2006

Implant recommendation as a replacement option after tooth loss for periodontal reasons.

PURPOSE: The aim of this study was to examine the frequency of implant recommendation by general dental practitioners to patients who had extractions as a result of periodontal disease and factors that influenced their decisions. MATERIALS AND METHODS: Dentists in each of 20 general dental practice centers in Kuwait were asked to document replacement options given to patients after all tooth extractions performed for periodontal reasons within a 30-day period. The association of demographic and medical/dental history variables with the decision to recommend an implant was statistically tested. RESULTS: A total of 711 patients with a mean age +/- of 47.34 +/- 0.45 years (range 18-96) had 2202 teeth extracted for periodontal reasons during the study period. Only 21 implants for 12 patients were offered as a replacement option (1.7%). Factors significantly associated with a less likelihood of implant recommendation included older age, male gender, diabetes mellitus, inadequate compliance with regular periodontal maintenance visits, inadequate oral hygiene practices, and anterior tooth types (P < 0.05; chi test). CONCLUSION: Dental implants were rarely recommended to patients losing their teeth for periodontal reasons by general dentists in Kuwait.

Adolescent↗

PubMed2006

"PASS" principles for predictable bone regeneration.

Guided bone regeneration is a well-established technique used for augmentation of deficient alveolar ridges. Predictable regeneration requires both a high level of technical skill and a thorough understanding of underlying principles of wound healing. This article describes the 4 major biologic principles (i.e., PASS) necessary for predictable bone regeneration: primary wound closure to ensure undisturbed and uninterrupted wound healing, angiogenesis to provide necessary blood supply and undifferentiated mesenchymal cells, space maintenance/creation to facilitate adequate space for bone ingrowth, and stability of wound and implant to induce blood clot formation and uneventful healing events. In addition, a novel flap design and clinical cases using this principle are presented.

Alveolar Ridge Augmentation↗

PubMed2006

The role of platelet-rich plasma in sinus augmentation: a critical review.

Although the lateral wall sinus lift is a predictable clinical procedure to increase vertical bone height resulting in implant success rates comparable to that of native bone, the issue of extended healing periods remains troublesome. Clinicians and researchers have investigated several methods, including addition of growth factors and peptides, to reduce this healing time and enhance bone formation within the subantral environment. Platelet-rich plasma (PRP) is an autologous blood product containing high concentrations of several growth factors and adhesive glycoproteins. The incorporation of PRP into the sinus graft has been proposed as a method to shorten healing time, enhance wound healing, and improve bone quality. This article reviewed pertinent literature assessing the effect of PRP on sinus augmentation. Currently, the literature is conflicting with respect to the adjunctive use of PRP in sinus augmentation. Factors that may contribute to this variability include variable/inappropriate study design, underpowered studies, differing platelet yields, and differing graft materials used. In addition, methods of quantifying bone regeneration and wound healing differ between studies. At present, because of limited scientific evidence, the adjunctive use of PRP in sinus augmentation cannot be recommended. Further prospective clinical trials are urgently needed.

Alveolar Ridge Augmentation↗

PubMed2006

Vertical bone augmentation: where are we now?

As the prevalence of implants has increased, so has the challenge to augment the remaining osseous structure to house those implants. The biggest surgical challenge clinically is to augment lost bone vertically. The purpose of this article is to review currently available techniques for achieving greater vertical dimension before implant placement. A literature search was conducted using MEDLINE to find all articles published between 1970 and 2004 regarding vertical bone augmentation. Following the literature search, all articles were reviewed and summarized in this review article of vertical bone augmentation. The results of the research showed that guided-bone regeneration, monocortical onlay grafting, and distraction osteogenesis have the potential to be applied to augment deficient areas vertically. The expectations of dimensional gain and bone quality are unique to each technique, as well as the potential complications. Distraction osteogenesis has had the greatest potential for vertical gain, while guided-bone regeneration and monocortical onlay grafting achieve similar results. The choice of procedure is to be based upon the patient's existing anatomy, degree of vertical deficiency, and willingness to participate in treatment.

Alveolar Ridge Augmentation↗

PubMed2006

Consensus conference on immediate loading: the single tooth and partial edentulous areas.

PURPOSE: A consensus conference was held to determine what the parameters should be for the immediate functional loading of the single-tooth implant restoration and short-span fixed implant-supported bridgework. MATERIALS: Forty-one clinicians and researchers presented cases and situations relating to the topic. A panel then distilled questions that were presented to the audience (430) at large. Answers were gleaned to formulate a consensus. RESULTS: Ten distinct answers evolved that constituted the essence of guidelines for clinicians to be aware of when undertaking immediate loading. These guidelines are contained within the body of the text. CONCLUSIONS: Extreme caution and adherence to a universal generic protocol are suggested for clinicians who are involved with single-tooth and short-span multiple-teeth implant replacements as related to immediate loading as defined within this text.

Dental Abutments↗

PubMed2006

Medical contraindications to implant therapy: part I: absolute contraindications.

In order to ensure implant success, it is essential to select patients who do not possess local or systemic contraindications to therapy. Hence, it is the purpose of this paper to review the medical diseases that reportedly preclude conventional dental implant treatment. Absolute contraindications to implant rehabilitation include recent myocardial infarction and cerebrovascular accident, valvular prosthesis surgery, immunosuppression, bleeding issues, active treatment of malignancy, drug abuse, psychiatric illness, as well as intravenous bisphosphonate use. Any of these conditions bar elective oral surgery, and require judicious monitoring by the physician as well as the dental provider. Noncompliance to the suggested protocol may, in the worst possible case, result in patient mortality.

Bone Density Conservation Agents↗

PubMed2006

Flow cytometric and morphological characterization of platelet-rich plasma gel.

UNLABELLED: BACKGROUND OF PROBLEMS: Platelet-rich plasma (PRP) gel is derived from an autogenous preparation of concentrated platelets and is widely used in implant dentistry as a vector for cell growth factors. However, limited data are available on its structure and composition. The present study was aimed at providing a flow cytometric and ultrastructural characterization of PRP gel. MATERIALS AND METHODS: Twenty PRP gel samples were obtained from healthy volunteers. These PRP gel specimens were prepared for transmission (TEM) and scanning electron microscopy (SEM) examination of their morphological ultrastructure. Flow cytometry with CD41-PE monoclonal antibody was used to detect platelet cells, as this antibody recognizes human-platelet-specific antigen CD41. RESULTS: Both SEM and TEM showed that PRP gel contains two components: a fibrillar material with striated band similar to fibrin filaments, and a cellular component that contains human platelet cells. Both techniques indicated that no morphological elements were bound between the cellular component and the fibrillar material. The cells were confirmed as platelet cells by flow cytometric study after incubation with specific monoclonal antibody CD41-PE. CONCLUSION: PRP gel contains a fibrillar and a cellular (largely human platelet cell) component. This unique structure may be capable of acting as a vehicle for carrying of cells that are essential for soft/hard tissue regeneration.

Animals↗

PubMed2006

Effects of a mineralized human cancellous bone allograft in regeneration of mandibular Class II furcation defects.

BACKGROUND: A solvent-preserved, mineralized human cancellous bone allograft (MBA) was recently developed. However, its effect in regenerating furcation defects remains to be determined. Hence, the aim of the study is to evaluate the effects of this newly introduced MBA, with and without a bioabsorbable collagen membrane, for the treatment of mandibular class II furcation defects. METHODS: Thirty subjects with Hamp's Class II buccal or lingual furcation defects in lower molars were randomly assigned to open flap debridement (OFD), MBA, or MBA with a bioabsorbable collagen membrane (guided tissue regeneration [GTR]+MBA) groups. Clinical and defect measurements were obtained at the initial visit and at 6-month reentry surgeries. The data were analyzed for intra- and intergroup comparisons and associations of treatment with probability of clinical improvement. RESULTS: Out of a total of 30 subjects, 27 individuals completed the study. Vertical bone fill (VBF) was -1.6+/-2.1 mm in OFD, 1.9+/-1.4 mm in MBA, and 0.7+/-0.9 mm in GTR+MBA groups. VBF in MBA and GTR + MBA groups was significantly higher than that in the OFD group (P<0.05). Horizontal bone fill (HBF) was 0.2+/-1.7 mm, 1.1+/-0.9 mm, and 1.1+/-0.9 mm for OFD, MBA, and GTR+MBA groups, respectively. However, HBF, recession, clinical attachment level gain, and probing depth reduction at furcations showed no differences among groups. CONCLUSIONS: Results obtained from this study indicate that solvent-preserved, mineralized human cancellous allograft, with or without collagen membrane, can significantly improve bone fill in mandibular Class II furcation defects. In addition, initial vertical defect depth was found to be the only factor that was associated with a higher probability of clinical improvement.

Adult↗

PubMed2006

Factors influencing treatment outcomes in mandibular Class II furcation defects.

BACKGROUND: Factors influencing treatment outcomes in furcation defects remain to be studied. Therefore, the aim of the study was to evaluate the association between factors and clinical parameters that may influence treatment outcomes in mandibular Class II furcation defects. METHODS: Twenty-seven systemically healthy subjects with a Class II buccal or lingual furcation defect in lower molars were treated. Clinical measurements (probing depth [PD], clinical attachment level [CAL], recession, mobility, plaque index [PI], and bleeding on probing [BOP]) and defect (vertical and horizontal defect depths) were obtained at initial and 6-month reentry surgeries. Treatment modalities (e.g., nine each in the following three groups: open flap debridement [OFD] alone, bone graft [BG], and bone graft plus a bioabsorbable collagen membrane [BG + C]), anatomic factors (presence of cervical enamel projection, presence of cervical restorations/fixed prosthesis, and location of furcations [buccal or lingual sides; first or second molars]), clinical parameters (initial mobility, initial PD at furcation, initial CAL at furcation, mean initial PD of the tooth, mean initial CAL of the tooth, initial horizontal PD at furcation, initial horizontal/vertical defect depth, PI, and BOP), and background factors (endodontic status, smoking status, and surgeon's experience) were analyzed for associations with probability of clinical improvement. RESULTS: The anatomic factors, clinical parameters, and background information were found to have no effect in influencing treatment outcome with the exception of initial vertical defect depth. An initial vertical defect depth >or=4 mm had a borderline significance (P = 0.06) of achieving a high probability of having a 1-mm vertical bone fill. In addition, treatment modality was found to be a major influence factor. Sites treated with BG were 16x more likely to have >50% vertical bone fill than open flap surgery. Furthermore, sites treated with BG were 64x more likely to have a 1-mm vertical defect fill compared to sites treated with OFD and 16x more likely to have a 2-mm vertical defect fill compared to sites treated with OFD or BG + C. However, the additional membrane does not enhance the regenerative outcomes achieved by BG alone. CONCLUSIONS: Initial vertical defect depth (>or=4 mm) and treatment modality (e.g., BG) were found to be the clinical parameter and factor that were associated with high probability of clinical improvement. Sites treated with BG, such as mineralized human cancellous allograft, were more likely to have greater vertical furcation defect fill than the conventional OFD surgery. Additional membrane placement does not enhance the treatment outcome achieved by BG alone.

Adult↗

PubMed2006

Esthetic buccal flap for correction of buccal fenestration defects during flapless immediate implant surgery.

BACKGROUND: Clinically, it is a tremendous challenge to create natural gingival esthetics after immediate or delayed implant placement. Hence, flapless immediate implant surgery has been proposed to overcome the shortfalls of these techniques. Nonetheless, one of the major limitations for this technique is its inability to correct localized horizontal/vertical deficiency, dehiscence, or fenestration without jeopardizing esthetic outcomes. Therefore, the aim of this paper was to present a new flap design, the esthetic buccal flap (EBF), aimed at overcoming this potential problem while maintaining the optimal esthetic appearance. METHODS: Five consecutively EBF-treated patients with simultaneous implant placement were included in this pilot case study. Clinical measurements were taken at the time of prosthesis insertion and 6 and 12 months after surgery. These included soft tissue height, papillae appearance, scar appearance, and mid-buccal probing depth. RESULTS: Data obtained from this pilot case study showed that soft tissue height was preserved, and papillae appearance remained the same as at presurgery. No scar tissue was reported in any cases. Mid-buccal probing depths remained consistent throughout the study. CONCLUSION: The results indicate that EBF, together with simultaneously guided bone augmentation, allows clinicians to correct apical buccal fenestration defects while maintaining the supraosseous soft tissue during flapless immediate implant surgery.

Adult↗

PubMed2006

Effect of flapless implant surgery on soft tissue profile: a randomized controlled clinical trial.

BACKGROUND: Flapless implant surgery has been suggested as one possible treatment option for enhancement of implant esthetics. METHODS: Twenty-four patients with a missing tooth in the premaxillary region were randomly assigned to one of two groups (12 each): immediate loading (IL) or delayed loading (DL) (loading after 4 months). An endosseous implant was placed in each patient via a flapless surgery. Clinical measurements including the papillary index (PPI) (0, no papilla; 1, less than half; 2, more than half but not complete fill; 3, complete fill; and 4, overfill), marginal levels of the soft tissue (ML), probing depths (PDs), modified bleeding index (mBI), modified plaque index (mPI), and the width of the keratinized mucosa (WKM) were performed at baseline (at the time of loading) and at 2, 4, and 6 months. RESULTS: The soft tissue profile remained stable up to 6 months, without significant differences between the two groups (mean PPI and ML at 6 months, 2.16 and 0.30 mm, respectively). Mean PPI in the IL group significantly increased from 1.50 at baseline to 2.09 at 2 months, and the significance remained up to 6 months (2.30 at 6 months) (P <0.05), whereas in the DL group, no significant changes were found from baseline to 6 months in mean PPI (2.06 at both time points). Mean PPI increased over time when two treatment groups were combined; however, no statistical significance was found. In ML, the difference at baseline between the two groups (-0.28 mm for DL versus 0.17 mm for IL; P <0.05) was no longer significant at 2 months (0 versus 0.08 mm for DL and IL, respectively) and thereafter (P >0.05). No significant differences were detected between groups at each time and over time in the other clinical parameters, PD, mBI, mPI, and WKM (P >0.05). CONCLUSIONS: The results of this study indicate that creeping attachment (i.e., soft tissue recovery) might occur within 2 months after IL. The study suggests that flapless implant surgery provides esthetic soft tissue results in single-tooth implants either immediately or delayed loaded. Other long-term randomized controlled clinical trials with a large sample size and comparison group (i.e., implant surgery with flap) are recommended to verify the conclusions drawn in this preliminary study.

Adult↗

PubMed2006

Surgical or non-surgical periodontal treatment: factors affecting patient decision making.

BACKGROUND: This study explored which factors affected patients' decisions to pursue either surgical or non-surgical periodontal treatment. METHODS: Data were collected from 74 patients at a regularly scheduled periodontal appointment, at which each patient was told that periodontal treatment was needed, and 2 weeks following the actual treatment. The surveys assessed the patients' decisions and potential determinants of these decisions. The dental anxiety scale-revised, the state-trait anxiety inventory, and the Iowa dental control index were used to measure psychosocial factors. RESULTS: Patients who decided to have surgery did not differ from patients who decided against surgery in sociodemographic variables such as gender, age, education, and socioeconomic status, nor in their desire for control over the treatment decision. However, they had less dental fear and less general anxiety than the non-surgery patients. Although the two patient groups did not differ in their responses concerning how well the dentists had informed them about the procedure, they differed in the degree of trust and rapport with their dentists. CONCLUSIONS: The less dentally fearful and anxious patients were in general and the more they trusted their provider and felt they had good rapport, the more likely they were to accept surgical periodontal treatment. These results stress the importance of good patient-provider communication.

Adult↗

PubMed2006

Relationship between salivary melatonin and severity of periodontal disease.

BACKGROUND: Melatonin possesses antioxidant, free-radical scavenging, and immunoenhancing properties that promote fibroblast activity and bone regeneration. The aim of this study was to examine the possible links between salivary melatonin levels and the severity of periodontal disease using the community periodontal index (CPI). METHODS: Thirty-seven patients with different degrees of periodontal disease were studied. Salivary and plasma melatonin levels (by radioimmunoassay), salivary/plasma melatonin ratio, and CPI status were collected for each patient. The Spearman correlation coefficient was used to analyze relationships among variables. RESULTS: Data showed a significant correlation between CPI and salivary/plasma melatonin ratios. When saliva volume was controlled for, a significant correlation (P<0.05) was found between lower salivary melatonin and a worse CPI. This finding suggests that melatonin may act as a protector against free radicals produced by inflammatory periodontal diseases. CONCLUSIONS: Salivary melatonin levels varied according to the degree of periodontal disease. As the degree of periodontal disease increased, the salivary melatonin level decreased, indicating that melatonin may act to protect the body from external bacterial insults. Therefore, melatonin may be potentially valuable in the treatment of periodontal diseases, although further research is required to validate this hypothesis.

Adolescent↗

PubMed2006

Surgical versus non-surgical periodontal treatment: psychosocial factors and treatment outcomes.

BACKGROUND: This research explored how patients with surgical versus non-surgical periodontal treatment differ in trait anxiety, depression, perceived stress, and well-being on the day of surgery and in their reported pain and use of pain medication 2 and 4 weeks after treatment. In addition, it was investigated how psychosocial factors affected reported pain, use of pain medication, and wound healing. METHODS: Data were collected from 70 dental patients (34 males and 36 females; average age: 54.79 years; SD=13.206) on the day of their periodontal treatment and 2 and 4 weeks after this treatment. The psychosocial factors (i.e., trait anxiety, depression, perceived stress, and well-being) were measured with standardized scales. The patients' providers assessed their wound healing 2 weeks after treatment. RESULTS: On the day of treatment, non-surgical patients had higher anxiety, depression, and stress, and poorer well-being than surgical patients. However, surgical patients reported a higher level of pain during the second week, and greater consumption of analgesics during the second and fourth week. Anxiety, depression, stress, and well-being correlated with the reported level of pain, the use of pain medication, and wound healing after periodontal treatment. CONCLUSIONS: Psychosocial factors (i.e., anxiety, depression, stress, and well-being) can affect the patients' quality of life on the day of periodontal treatment and the pain experience and medications used after surgical and non-surgical periodontal therapy (4-week period). Patient-provider communication should address the role of these factors in the treatment process.

Adult↗

PubMed2006

Significance of keratinized mucosa in maintenance of dental implants with different surfaces.

BACKGROUND: The need for keratinized mucosa (KM) or immobile keratinized mucosa (i.e., attached mucosa [AM]) for the maintenance of osseointegrated endosseous dental implants has been controversial. The purpose of this study was to investigate the significance of KM in the maintenance of root-form dental implants with different surfaces. METHODS: A total of 339 endosseous dental implants in place for at least 3 years in 69 patients were evaluated. The width of KM and AM, modified plaque index (mPI), gingival index (GI), modified bleeding index (mBI), probing depth (PD), and average annual bone loss (ABL) were measured clinically and radiographically by a masked examiner. Based on the amounts of KM or AM, implants were categorized as follows: 1) KM <2 mm (KL); 2) KM > or =2 mm (KU); 3) AM <1 mm (AL); and 4) AM > or =1 mm (AU). Implants were further subdivided into the following four subgroups based on their surface configurations: 1) smooth surface implants (SI) with KM <2 mm (SKL); 2) SI with KM > or =2 mm (SKM); 3) rough surface implants (RI) with KM <2 mm (RKL); or 4) RI with KM > or =2 mm (RKM); or 1) SI with AM <1 mm (SAL); 2) SI with AM > or =1 mm (SAM); 3) RI with AM <1 mm (RAL); or 4) RI with AM > or =1 mm (RAM). The effect of KM or AM on clinical parameters was evaluated by comparing the different KM/AM groups. In addition, the significance of the presence of KM on implant prostheses types (i.e., fixed versus removable) and on implant locations (i.e., anterior versus posterior) was evaluated. RESULTS: Comparison of ABL among the four subgroups in KM or AM failed to reveal statistically significant differences (P >0.05); however, statistically significantly higher GI and mPI were present in SKL or SAL compared to the other three subgroups (P <0.05). GI and mPI were significantly higher in KL (0.94 and 1.51) than KU (0.76 and 1.26) and higher in AL (0.95 and 1.50) than AU (0.70 and 1.19) (P <0.05), respectively. The difference in GI between posterior implants with or without an adequate amount of KM was also significant (P <0.05). CONCLUSIONS: The absence of adequate KM or AM in endosseous dental implants, especially in posterior implants, was associated with higher plaque accumulation and gingival inflammation but not with more ABL, regardless of their surface configurations. Randomized controlled clinical trials are needed to confirm the results obtained in this retrospective clinical study.

Adult↗

PubMed2006

Flap thickness as a predictor of root coverage: a systematic review.

BACKGROUND: Thick gingival tissue eases manipulation, maintains vascularity, and promotes wound healing during and after surgery. A few recent case reports correlate greater flap thickness to mean and complete root coverage after mucogingival therapy for recession defects. The aim of this systematic review is to appraise the current literature on this subject and to combine existing data to verify the presence of any association between gingival thickness and root coverage outcomes. METHODS: Human studies that reported the number and class of recessions, measured flap thickness at a well-defined location, described the method of root coverage used, followed results for at least 3 months, and detailed mean root coverage underwent review and statistical analysis. Investigations were scored from 1 to 5 based on methodological quality. Weighted gingival thickness and weighted mean root coverage was calculated based on standard error. Statistical analysis used the Mann-Whitney test, analysis of variance (ANOVA), and linear regression to determine any correlation between a number of factors (i.e., thickness, treatment type, and follow-up time) and mean and complete root coverage. A significant P value was set at <0.05. RESULTS: Fifteen investigations met the inclusion criteria. All of these reported at least 0.7 mm of flap thickness, although measurement locations varied. Treatment modalities included coronally advanced flap, connective tissue graft, and guided tissue regeneration with and without adjuncts. A significant moderate correlation occurred between weighted flap thickness and weighted mean root coverage and weighted complete root coverage (r = 0.646 and 0.454, respectively). According to Mann-Whitney analysis, a critical threshold thickness >1.1 mm existed for weighted mean and complete root coverage (P <0.02). The type of treatment rendered also influenced root coverage. Further simple linear regression revealed a high correlation between weighted thickness and weighted mean root coverage in connective tissue grafting and guided tissue regeneration (r = 0.909 and 0.714, respectively) but not coronally advanced flap therapy. Study score and follow-up time did not affect the percentage of root coverage. CONCLUSION: Within the limits of this review, a positive association exists between weighted flap thickness and mean and complete root coverage.

Connective Tissue↗